· ict-3 at nelamangala substation 19-05-2019 at 16:11 hrs as per fir, ict-3 got tripped on...

Agenda for the 85th

Meeting of PCSC scheduled to be held on 31st July, 2019 Page 1

SOUTHERN REGIONAL POWER COMMITTEE BENGALURU

Agenda for the 85th Meeting of Protection Coordination Sub-Committee of SRPC to be held on 31st July, 2019

1. Introduction

2. Confirmation of Minutes of last PCSC meeting

Confirmation of minutes of 84th Protection Coordination Sub-Committee meeting held on 26th – 27th June 2019.

3. Grid Occurrences

3.1 Grid Disturbances (GD), Grid Incidences (GI), trippings due to failure of Auto-reclosing

(A/R) and mal-operation of PLCC equipment that occurred during the period May - June, 2019, given at Annexure-I, would be discussed in the PCSC meeting.

Constituents are requested to furnish the following information in respect of the above grid occurrences to have fruitful discussions:

(a) Single line diagram of the station with switching devices, CT, PT and relay details.

(b) Cause of the tripping & Remedial Action taken

(c) Relay setting details

Constituents are requested to furnish/bring full particulars of the tripping events pertaining to their system.

3.2 In compliance of Regulations 5.2 (r) of IEGC, the Constituents are required to furnish

the following information in respect of Grid Occurrences within 24 hr. of occurrence of the same to SRLDC/ SRPC: (a) First Information Report (FIR) (b) Event Logger (EL) output (c) Disturbance Recorder (DR) output (d) Trip event analysis report (with pre and post fault system conditions) Non-furnishing of tripping details (FIR/DR/EL/TR) for the period 16.05.2019 – 30.06.2019 had been brought to Constituents’ notice vide letters (i) No. SRPC/ SE-III/ PCSC/ 2019/ 3504-17 dated 12.06.2019, (ii) No. SRPC/ SE-III/ PCSC/ 2019/ 3651-69 dated 25.06.2019 and (iii) No. SRPC/ SE-III/ PCSC/ 2019/4228-64 dated 08.07.2019. Non-compliance in this regard would be discussed in the meeting.

4. Submission of Reports/ Compliance by Constituents

4.1 Status of implementation of Recommendations Protection Coordination

Sub-Committee (PCSC), which are pending

The status of implementation of PCSC recommendations (up to 84th PCSC meeting), which are pending is given at Annexure-II. The latest status on the same may please be sent latest by 25.07.2019.

Agenda for the 85th


4.2 Remedial measures for "Transmission Elements under Forced Outage"

The Constituents are requested to furnish the remedial measures/ actions taken by them for the tripping events as circulated vide this office emails. (Annexure-III)

The tripping events are based on the daily reports at SRLDC website http://srldc.in/Reports.aspx under the menu: Reports->Daily-> "TL under Forced Outage").

4.3 Certificate for Healthiness of Batteries

As per the MoP direction, given in pursuant to recommendations of the Enquiry Committee (NEW grid disturbance on 30th & 31st July, 2012), the monthly certificate for healthiness of batteries, installed at 220 KV and above voltage level Substations (for power supply to Relays, RTUs and PLCC equipment) are required to be obtained by RPC’s from their respective Constituents and furnish the same to CEA/ MoP.

With reference to above, the Constituents have been requested to submit the certificate on healthiness of batteries on monthly basis (i.e. status for a month shall be sent by the 7th day of the following month) to SRPC Secretariat.

The sought status for the month of May, 2019 is awaited from the following SR-Constituents:

KPCL, KPTCL, TANGEDCO, NTPC (KYLM) 5. Maintenance & Support (AMC) renewal of PSSE Licenses

In 2012, POWERGRID had coordinated one-time capacity building exercise for various stakeholders, under which 35 No. of PSSE Licenses were distributed among SR utilities. The maintenance and support for supplied licenses was for a period of 6 years, which had ended on 30th November 2018. A communication regarding renewal of the maintenance and support for the above Licenses has been received from M/s Siemens (Annexure-VIII), with a request to RPC to coordinate the renewal. All Utilities who wish to renew the licenses may please intimate the willingness along with the confirmation letter during the meeting so that the matter may be appropriately taken up with M/s Siemens.

In the 84th PCSC Puducherry Electricity Department (for One License) and CPRI (for Two Licenses) have expressed willingness to renew the AMC. Other utilities informed, then, that they would revert. The view on the matter may be updated for further needful action.

6. Nominations of Nodal Officers for Conduction of Protection Audit of various 220 kV

& above Stations in Southern Region

As per the discussions of PCSC-80 conduction of protection audit of various 220 kV & above Stations in Southern Region was approved in 35th SRPC meeting. Nominations in this regard were sought from all Utilities vide SRPC letter No. SRPC/SE-III/ PA/ 2019/3589-3618 dated 19.06.2019. Based on consolidation of responses received in this regard till now nominations have been received from PGCIL (SR-I), PGCIL (SR-II), NPCIL (KGS), NTPC, TSTRANSCO, TANGEDCO (TTPS) and TANTRANSCO. All remaining utilities are requested to kindly furnish the nominations by 20.07.2019 for further necessary action.

7. Other Protection Issues, if any, with the permission of the Chair

http://srldc.in/Reports.aspx

Agenda for the 85th


8. Sending Agenda items for the PCSC meetings

As per the Guidelines of CEA/MOP, it has been decided to conduct the PCSC meetings on monthly basis. It is requested that Agenda Items for the PCSC meetings, if any, may please be sent latest by 5th working day of the month to SRPC Secretariat to compile and circulate the same so as to have fruitful discussions in the PCSC meetings.

9. Date of next PCSC meeting

The schedule of 86th meeting of PCSC may be decided.

*****

Grid Occurrences to be discussed in the 85thMeeting of PCSC scheduled to be held on 31st July, 2019 1/6

Grid Occurrences - 85

For all tripping events involving failure of substation equipment, Constituents are requested to kindly furnish the SLD or equivalent pictorial representation showing (i) Location of the fault, and (ii) Bus-bar arrangement/ Configuration of feeders and other connected equipment with proper CB positions (OPEN/ CLOSE) at the time of occurrence of the fault.

I. Details of Grid Disturbances:

Sl. No.

Details of Event Date &Time Reason Remarks Category

1

Complete outage of 220kV 220/110kV Palakkad Substation of KSEB

04-06-2019 at 14:02hrs

Testing of Bus Coupler CT was being carried out during which LBB trip got initiated and resulting in tripping of Bus-2. This resulted in the tripping all the connected elements at 220kV Palakkad Bus-2 leading to complete loss of supply

Load loss – 268 MW

GD-1

2

Complete outage of 220kV Pothenkode Substation of KSEB

04-07-2019 at 01:18 hrs

Triggering incident was failure of suspension insulator of 220kV Pothenkode – Trivendrum ckt-2. Bus bar protection of Bus-1 and Bus -2 operated resulting in tripping of all connected elements.


GD-1

3 Complete outage of 220kV Malaparamba SS of KSEB

29-05-2019 at 01:12 hrs

Triggering incident was R-phase to Earth fault in 220kV Malaparamba Areakode line due to insulator decapping . 220kV Malaparamba Substation was being radially fed from 220kV Areakode


GD-1

II. Details of Grid Incidents:

Sl. No. Details of Event Date &Time Reason Category

1 Tripping of 400/230kV MANALI ICT-3

13-05-2019 at 2:42 hrs

ICT-3 got tripped on the activation of HV REF protection. During test charging of 110 kV Manali-ETPS -1 , the 110 kV ETPS -1 got tripped on the activation of Back up relay and Distance relay failed to act

GI-2

2 Tripping of 400kV Madurai-Udumalpet line

16-05-2019 at 18:54 hrs

400kV Udumalpet Madurai line tripped only at Udumalpet end on line under frequency protection operation due to suspected R-ph CVT problem.

GI-2

3 Tripping of 400kV Kurnool-Srisailam line

17-05-2019 at 14:10 hrs

line tripped only at Srisailam end on Zone-3 distance protection operation during Y phase to B phase fault in 220kV Narnoor Somayajulapalli line-1

GI-2

Annexure-I


4 Tripping of 220kV Ambewadi-Ponda line

18-05-2019 at 12:13 hrs

B phase to Earth fault in the line. Line tripped on Zone 3 distance protection operation at Ambewadi end

GI-1

5 Tripping of 400/220 kV ICT-3 at Nelamangala substation

19-05-2019 at 16:11 hrs

As per FIR, ICT-3 got tripped on operation of High Set Over current trip on 400kV side

GI-2

6 Tripping of 400/220 kV ICT-2 at Ghani substation

21-05-2019 at 15:13 hrs

ICT-2 tripped on LV Earth fault protection. 400kV Ghani-Narnoor line-1 had tripped on B-phase to earth fault.

GI-2

7 Tripping of 400/220 kV ICT-3at Mamidapalli

21-05-2019 at 20:43 hrs

ICT tripped on PRV-1 indications due to ingress of moisture into the relay

GI-2

8 Tripping of 765/400kV ICT-1 and 2 at Kurnool substation

21-05-2019 at 18:11 hrs

ICT 1 and 2 got tripped due to maloperation of Bucholz relays during the charging of 400KV Kurnool-Nanoor line 1 which tripped on SOTF

GI-2

9 Tripping of 220KV Sabarigiri-Theni line

23-05-2019 at 16:12 hrs

Line tripped on operation of DEF at Theni end

GI-1

10 Tripping of 400kV Sigareni-Sundilla line-2

24-05-2019 at 18:21 hrs

Line tripped to operation of OV Stg-1 protection operation at Sundila end and DT received at Singareni end. Difference in phase voltages is observed at Sundilla end DR (Vr-262kV, Vy-240kV and Vb-214kV).

GI-2

11 Tripping of 400kV Hoody-Yelahanka line-1

25-05-2019 at 20:41 hrs

Line tripped at Hoody end only and was holding from Yelahanka.

GI-2

12 Tripping of 400/220 kV ICT-1at Guttur Substation

26-05-2019 at 10:00 hrs

LV side of 400kV/220kV 315MVA ICT#1 Guttur got tripped due to CB lockout (B phase)because of low SF6 gas in the CB

GI-2

13 Tripping of 400kV NPS Nellore line-1 & 2

27-05-2019 at 17:42 hrs

400kV NPS Nellore-PG line-2 tripped at NPS end due to suspected maloperation of group B protection and DT was sent to Nellore-PG end. 400kV NPS Nellore-PG line-1 got tripped due to operation of SPS

GI-2

14 Tripping of 230kV Theni-Sabarigiri line

29-05-2019 at 18:39 hrs

3 phase to earth fault occurred in line. Tripped on ground over current protection 67N at Sabarigiri and Zone-2 at Theni end

GI-1

15 Tripping of 400/220 kV ICT-1 and 400kV RTPS-RAICHUR PG line-2

29-05-2019 at 12:43 hrs

Due to spurious operation of Tie breaker LBB, 400/220 kV ICT-1 and 400kV RTPS-Raichur PG 2 got tripped at RTPS end and DT was sent to Raichur PG end

GI-2

16

Tripping of 400kV Tumkur-Bidadi line-1&2, 400kV Tumkur-Cuddapah line-2, 400kV Tumkur-Pavagada line-2

29-05-2019 at 6:11 hrs

Lines tripped due to Y-N & Y-B phase to earth fault

GI-2

17 400 kV Ghani – Narnoor line-1, 400 KV Jamalamadugu-

30-05-2019 at 00:48 hrs

Triggering incident was Y-ph to B-ph fault in the 400kV NarnoorJammalamadugu line-1 & 2 due to falling of Y-ph CVT jumper on B-

GI-2

Annexure-I


Kurnool line-1, 765/400 kV ICT-1&2 at Kurnool

ph during heavy wind. At the same time, 400kV GhaniNarnoor tripped only at Ghani end on operation of Zone-1 distance protection. 765/400 kV ICT-1 & 2 at Kurnool PG also got tripped on HV side Directional Overcurrent (DOC) protection.

18 Tripping of 765/400kV ICT-2 at Kurnool

02-06-2019 at 17:41 hrs

ICT-2 got tripped on operation of Back up directional over current due to through fault (Y-B phase fault).

GI-2

19 Tripping of 400kV JSW-Guttur line

02-06-2019 at 18:17 hrs

Line tripped due to OV St-1 protection operation at JSW end and DT was sent to Guttur end. At Guttur end B ph voltage was observed to be lesser comparing to R ph and Y ph(Vr-249kV, Vy-255kV and Vb-230kV).

GI-2

20 Tripping of 220kV Idukki-Udumalpet line

05-06-2019 at 15:13 hrs

Triggering incident was R-Y-Earth fault in the line. Carrier aided protection not operated at Udumalpet end.

GI-1

21 Tripping of 400kV JSW -Guttur line and 400 kV Kaiga - Guttur line-2

05-06-2019 at 18:27 hrs

Y-phase to earth fault occurred in 400kV Kaiga-Guttur line-2. A/r was successful at Guttur end. At Kaiga end A/r was not attempted and breakers got tripped due to operation of Pole discrepancy (1.65 Sec). 400kV JSW-Guttur line tripped on operation of over-voltage at Guttur and direct trip was received at JSW. From DR of Guttur, it is observed that there was swell in R & Y phase voltage for few cycles

GI-2

22 Tripping of 400kV Dhoni-Munirabad line

06-06-2019 at 02:01 hrs

Line got tripped at Dhoni end. From DR Zone-3 start, PSB and A/r block was observed.

GI-2

23 Tripping of 400kV N.P.Kunta-Hindpur line-2

09-06-2019 at 18:14 hrs

R-phase to earth fault occurred in line. Line tripped due to operation of over-voltage stg-2. Voltage swell was observed in DR (R-phase to earth voltage-462kV)

GI-2

24 Tripping of 400kV Vemagiri-Vijayawada line-3

10-06-2019 at 9:18 hrs

line tripped due to mal-operation of line Reactor Differential relay at Vijayawada end and DT was received at Vemagiri end

GI-2

25

Tripping of 400kV KTPS-VII - Julurupadu Line-2 & tripping of 400/220kV ICT-1&2 at Julurupadu substation

10-06-2019 at 8:22 hrs

Y-phase to earth fault occurred in 400kV KTPS-VII - Julurupadu Line-2. Operation of over-voltage stg-2 resulted in tripping of line. 400/220kV ICT-1&2 at Julurupadu on operation of over flux protection.

GI-2

26

Tripping of 220kV Sedam-RTPS line-1&2 and 220kV Sedam-Tandur line

14-06-2019 at 02:00 hrs

Tripped on Directional Earth Fault indications in Main-2 relay at Tandur end for fault at Raichur end.Sedam end details not furnished.

GI-1

27 Tripping of 400kV Vemagiri-GMR line-1&2

14-06-2019 at 09:33 hrs

Line-1 tripped on Y-Phase to earth fault due to Y-Phase LA failure at Vemagiri end. Line-2 tripped at GMR end only

GI-2

28 Tripping of 400/220kV ICT-2 at Hoody

16-06-2019 at 19:20 hrs

ICT-2 got tripped on operation of over-flux protection

GI-2

Annexure-I


substation

29 Multiple tripping at 220kV Nunna substation

16-06-2019 at 06:16 hrs

Triggering incident was failure R phase CT of 220/132kV transformer (connected to 220kV Bus-2) in 220kV Nunna station. Bus-2 bus bar protection operated resulting in tripping of elements connected to 220kV Bus-2. 2.63 Seconds later a 2nd fault occurred in Bus-1 due to fault getting extended from Bus-2 CT failure which inturn resulted in tripping of elements connected to 220kV Bus-1

GI-1

30

Tripping of 400kV Hiryur-Nelamangala line-1 and 400kV Gooty-Nelamangala line

22-06-2019 at 04:06hrs

400kV Hiryur-Nelamangala line-1 : 'Y' phase bushing of Hiriyur line-1 reactor failed at Nelamangala end resuting in a R-Y phase fault. Direct trip was sent to Hiryur. 400kV Gooty-Nelamangala line : Line tripped at Nelamangala end only due to mal-operation of Main-2 didtance protection relay (THR).

GI-2

31 Tripping of 400/220kV ICT-1&2 at Munirabad substation

24-06-2019 at 20:50 hrs

400/220kV ICT-1&2 at Munirabad end got tripped due to operation of High set of backup earth fault relay during failure of Y phase CT in 220kV Munirabad-Kalyani steel feeder at Kalyani steel end

GI-2

32

Tripping of HVDC Talcher-Kolar Pole-1

31-05-2019at 18:30

hrs

Pole 1 tripped on Line fault. Pole-1 restarted three times and went into RVO mode. The fourth fault caused tripping of the pole.Pole-2 went to ground return mode. Remarks: SPS Trip Signal-1 and Trip Signal-2 operated at Kolar end since total power loss was ~1700 MW

Tripping of HVDC Talcher-Kolar Pole-1&2

05-06-2019 at 19:01 hrs

HVDC Talcher-Kolar Pole-1 tripped on receipt of ESOF (Emergency Switch On to Fault) signal at Kolar from Talcher end. Pole-2 went to metallic return mode with a power flow of 900MW at Kolar end. Subsequently at 19:02 Hrs, HVDC Talcher-Kolar Pole -2 also tripped due to operation of undervoltage protection at Kolar end. Remarks: After tripping of Pole-1 SPS Trip Signal-1 operated leading to total load relief of 700MW.


08-06-2019 at 12:10 hrs

Pole 1 tripped on receipt of ‘ESOF” from other side at 12:10 Hrs. Pole-2 shifted to metallic return mode of operation.

Annexure-I


Remarks: SPS Trip Signal-1 operated at Kolar end leading to total load relief of 700MW.


12-06-2019 at 12:24 hrs

While carrying out the switching operation of charger-2 to Charger-3 for enabling maintenance by OEM, Pole -2 got tripped due to suspected over voltage in 24V system. After tripping of Pole-2, Pole-1 continued to operate in metallic return mode Remarks: SPS at Kolar did not operate since total power loss after tripping of Pole-2 was less than 500 MW

33

220kV Lower Sileru-KTPS line

01-06-2019 at 00:00 hrs

R-phase to ground fault. Auto-reclose was successful at Lower sileru end. A/r is not enabled at KTPS


02-06-2019 at 15:30 hrs

R-phase to earth fault occurred in line. Auto-reclose was successful at Lower sileru end. A/r is not enabled at KTPS.


09-06-2019 at 11:58 hrs

B-phase to earth fault occurred in line. Zone-2 operated at KTPS and Earth fault at Lower sileru. Suspected high resistance fault.


12-06-2019 at 14:23 hrs

Y-phase to earth fault occurred in line. Auto-reclose was successful at Lower Sileru end. A/r is not enabled at KTPS

III. Details of Trippings due to Failure or Non-operation of Auto-Reclose:

Sl. No. Element Date & Time Reason

1 Tripping of 400kV Ghani-Narnoor line-1

21-05-2019 at 15:11 hrs

B-phase to earth fault occurred in line. Auto-reclose was not successful as fault was persistent in nature. Fault was cleared in zone-2 time during A/r attempt

2 Tripping of 400 kV Kudgi PG - Tumkur line - 2

21-05-2019 at 15:30 hrs

Y-phase to earth fault occurred in line. Auto-reclose was successful at Tumkur. At Kudgi end Auto-reclose was not attempted

3 Tripping of 400kV Talarichevu - Jamalamadugu ckt-1

21-05-2019 17:51 hrs

B -ph to ground fault in the line.. Auto reclose operated at Talarichevu end but tripped on persistent fault. Auto reclose not attempted at Jamalamadugu end

4 Tripping of 400kV Talarichevu - Jamalamadugu ckt-1

22-05-2019 at 19:21 hrs

R phase to Earth fault in the line. At Jammalamadugu end A/r operated and line tripped due to persistent fault. Main CB A/r not attempted at Talarichevu

Annexure-I


5 Tripping of 400 kV Kudgi PG –Tumkurline-2

23-05-2019 at 22:05 hrs

Y-phase to earth fault occurred in line. Auto-reclose was successful at Tumkur end. At Kudgi(PG) end A/r was not attempted due to A/r block

6 400 KV Thiruvelam – Palavadi line-1

28-05-2019 at 18:04 hrs

B-phase to earth fault. A/r attempt could not be validated.

7 Tripping of 400kV Pugalur-Karaikudi line-1

31-05-2019 at 17:44 hrs

R-phase to earth fault occurred in line. Auto-reclose was successful at Karaikudi, At Pugalur end there was 3-phase trip

8 Tripping of 400kV Ramagundam-Ghanapur line

02-06-2019 at 13:23 hrs

R-phase to earth fault occurred in line. Auto-reclose was successful at Ghanapur and A/r was not attempted at Ramagundam due to DT receive

9 Tripping of 400kV Kalikiri-RYTPP line-2

02-06-2019 at 19:15 hrs

B-phase to earth fault occurred in line. Auto-reclose was successful at Kalikiri and A/r not attempted at RYTPP due to A/r lockout

10 Tripping of 400kV VTPS-SURYAPET line-1

02-06-2019 at 13:15 hrs

B-phase to earth fault occurred in line. Auto-reclose was successful at Suryapet end. 2nd fault during reclaim time resulted in three phase trip. At VTPS end A/r was not attempted

11 Tripping of 765 KV Kurnool - NPS line-1

02-06-2019 at 17:41 hrs

R-phase to earth fault occurred in line. A/r not attempted due to PLCC channel fail.

12 Tripping of 400KV-Maheshwaram PG-Mahbubnagar line-1

06-06-2019 at 19:18 hrs

Y phase to Earth fault in the line. A/r not operated at Mahbubnagar

13 Tripping of 400 kV JSW -Guttur line

08-06-2019 at 13:13hrs

B-phase to earth fault occurred in line. A/r was not successful as fault was persistent. A/r not attempted at Guttur.

14 Tripping of 400kV Kaiga-Guttur line-2

16-06-2019 at 19:20 hrs

R-phase to earth fault. Auto-reclose attempt at Guttur end was not successful as fault was persistent in nature. Attempt for A/r could not be established from Kaiga end EL

IV. Details of Trippings due to PLCC mal-operation:

Sl. No. Element Date & Time Reason

1 Tripping of 400kV Julurupadu-Managuru line -2

20-05-2019 at 15:57 hrs

Line tripped at Julurupadu end only on direct trip receive

2 Tripping of 400kV KhammamMamidapally line-1

27-05-2019 at 18:16 hrs

Line tripped only at Mamidapally end due to suspected PLCC maloperation

Annexure-I


3 Tripping of 765 kV Raichur- Kurnool line- 2

02-06-2019 at 17:41 hrs

Line tripped on operation of Over voltage stage-1 at Kurnool end. Direct trip was not sent to Raichur due to failure of PLCC channel at Kurnool and line was holding from Raichur.

4 Tripping of 765 KV KURNOOL - NPS 2

02-06-2019 at 17:41 hrs

Line tripped on operation of over voltage stage-1 protection at Kurnool. Direct trip was not sent to NPS due to PLCC channel fail

5

Tripping of 400kV Warangal-Bhoopalapalli line-1 &Boopalppalli Chandlapur line-1

08-06-2019 at 1:35 hrs

400kV Warangal-Bhoopalapalli line-1 line tripped only at Boopalappalli end on OV st-1 protection operation and DT was not sent to Warangal end due to failure of both PLCC channels. 400kV BoopalppalliChandlapur line-1 tripped at Boopalpalli end due to DT Receive

6 Tripping of 400kV Kayathar-Kanarpatty line-1 & 2

10-06-2019 at 12:22 hrs

Line-1 & 2 tripped at Kanarpatty end due to spurious DT sent from kayathar end. Feeder did not trip at Kayathar end

7 Tripping of 400kV Ramadugu-Singareni line

11-06-2019 at 08:24 hrs

Line tripped due to Direct Trip receive at Ramadugu end

Annexure-I

Meeting

No /

Index

Details of Event Date & Time Reason PCSC Recommendations Utility responsible for

Implementation

Status of Implementation of PCSC Recommendations Remarks Latest Status

(To be filled up by the Constituent)

PGCIL (SR-I) mail received on 27-04-2016:

1. The firmware of REL670 is being upgraded. ------- Completed.

2. The recording of events in msec interval is being taken up with OEM. Henceforth,

for analysis purpose, we will provide larm list which has msec time stamp. --------

Completed.

3. End to end testing of PLCC code transmision and tuning of channels carried out. ----

--- Completed.

4. Procurement of differential protection for 400kV NPS-NLR D/C and 400kV RCR-

RTPS-D/C is under tendering. The legends modified in Event/alarm list. Provision of

diff. relay for all short lines emanating from NPS is being taken up with our

corporate.

----- Pending.

PGCIL(SR-I) RVMD 14-07-2016:

4. The proposal for procurement of Line differential Protections for 400kV Raichur -

RTPS-1 & 2 and 400kV Nellore - NPS - 1 & 2 lines has been approved and tender is PGCIL (SR-I) Mail dated 15.12.2017:

4. LDP relays procurement is under process. Procurement will be completed by Feb-

2018. TPCIL has to give written confirmation for LDP relay procurement. For want

of written confirmation from TPCIL, PGCIL approving authority has withheld the

LDP proposal.

Review Meeting dated 19.12.2017:

4. PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL

to complete procurement of LDP relays. To this, PCSC forum asked TPCIL to submit

written confirmation to PGCIL (SR-I) by 29.12.2017. PGCIL (SR-I) assured that

with receipt of above confirmation from TPCIL by Dec, 2017, they would be able to

complete the work by FEbruary, 2018.

APTRANSCO informed that they would be able to implement LDP from their &

APGENCO side by April, 2018.

In this regard, PCSC forum made it clear that the recommendation is about providing

LDP as both Main-I & Main-II relays on all stated lines in Nellore Complex, ans

Status of Pending Implementation of PCSC Recommendations as on 15.07.2019 (up to 84th Meeting)

KPTCL Mail dated 27-05-2015:

1. KPTCL has taken action to provide bus bar protection to 220kV buses. --- Pending

2. Over current relay Settings of ICTs to be reviewed by PGCIL.

--- Pending

3. --- Pending

KPTCL Mail dated 29-07-2015:

1. Initial Tendering stage. --- Pending

2. --- Pending

3. --- Pending

KPTCL Mail dated on 23-01-2016:

1. Detailed estimate prepared for taking up the work. CEE, Transmission Zone,

Gulbarga will take up necessary procurement and further execution. --- Pending

2. --- Pending with PGCIL (SR-I).

3. --- Pending

PGCIL (SR-I) Mail dated 14.07.2016:

2. Relay settings of all the stations in SRTS-1 were derived as per Ramakrishna

Commettee recomendations and implemented" --- Completed.

KPTCL Mail dated 16.12.2017:

1) & 3). DPR is approved. Tender is to be called by CEE,TZ Kalaburgi --- Pending


1. KPTCL informed that Tenders for providing BBP would be called in Jan-Feb,

2018; Supply of the same is targeted by September, 2018; Erection & Commissioning

is targeted by January, 2019

--- Pending

3. PGCIL (SR-I) informed that time-synchronization of 220 kV side is in place. ---

Completed.

KPTCL mail dated 19.12.2018:

1. DPR preapared for the work of providing Bus Bar Protection to 220kV buses at

Guddadahally is approved. Tender is to be invited by CEE,TZ .


1. Tender would be floated in January 2019. Works would be completed in 6 months

16-07-201434/I/6 400/220 kV ICT-1 & 2 at

Munirabad

As reported directional over current relay of ICT’s

operated due to snapping of line jumper in 220kV

Lingapur line.

1. Bus bar protection shall be provided by asset

owner ( i.e KPTCL).

2. Settings for main distance protection &

Overcurrent protection shall be examined and

reviewed.

3. Time synchronization of the Substation shall be

ensured.

KPTCL/

PGCIL (SR-I)

Pending

(with KPTCL)

Multi-Utilities

Complete outage of TPCIL

power station

PendingPGCIL (SR-I),

MEPL, SEL, TPCIL,

NCC

Running units at Thermal Powertech power Station

tripped due to tripping of 400kV Nellore pooling

station (NPS)-TPCIL line and 400kV Nellore pooling

station (NPS)-NCC line

30-12-2015 at

06:02hrs

50/I/2 1.PGCIL (SR-I) to furnish Action Taken Report on the

findings of OEM on relay mal-operation at NPS end

on 400 kV NPS – NCC line to PCSC forum.

2. PGCIL (SR-I) to appropriately configure Station

Event Logger at NPS to record events at msec interval.

3. PGCIL (SR-I) to carry out PLCC end-to-end testing

in coordination with TPCIL for 400 kV NPS –TPCIL

line.

4.PGCIL (SR-I), MEPL, SEL, TPCIL & NCC to take

steps to provide line differential protection at their

respective ends on all 400 kV lines (except Gooty line)

emanating from Nellore Pooling Station, and furnish

an action plan to implement the same.

Annexure-II

Page 1 of 30

PGCIL (SR-I) mail dated 20.06.2018:

PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays.

Tenders are invited from bidders & tender floated. Technical bid opening in this

week.


PO placed on M/s GE & TD India Ltd on 24.09.2018. Supply of relays will be

completed by Jan'2019 and commissioning by Mar'19.


4. PGCIL-SR1: LDP relays (Main-1) commissioned in 400kV NPS-TPCIL-1 Line

during opportunity shutdown. NPS-NCC D/C & NPS-TPCIl D/C lines LDP relay

retrofitting planned in June & July -2019.

In 154th OCC meeting SRLDC/SRPC has advised to re-schedule LDP

commissioning tentatively to Sep/Oct’2019.

APTRANSCO Mail Dated 24.04.2018:

ABB make LDP relays inspection is completed. SNEIDER make LDP relays

inspection yet to be completed. Delivery of relays expected in the 1st weak of May-

2018.


SNEIDER make LDP relays inspection yet to be completed.Delivery of relays

expected in the month of june 2018.


PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays.


week.


ABB make LDP relays are delivered. Schneider make LDP relays inspection to be

offered by the company.


Complete outage of TPCIL

power station

PendingPGCIL (SR-I),

MEPL, SEL, TPCIL,

NCC

Running units at Thermal Powertech power Station

tripped due to tripping of 400kV Nellore pooling

station (NPS)-TPCIL line and 400kV Nellore pooling

station (NPS)-NCC line

30-12-2015 at

06:02hrs

50/I/2 1.PGCIL (SR-I) to furnish Action Taken Report on the

findings of OEM on relay mal-operation at NPS end

on 400 kV NPS – NCC line to PCSC forum.

2. PGCIL (SR-I) to appropriately configure Station

Event Logger at NPS to record events at msec interval.

3. PGCIL (SR-I) to carry out PLCC end-to-end testing

in coordination with TPCIL for 400 kV NPS –TPCIL

line.

4.PGCIL (SR-I), MEPL, SEL, TPCIL & NCC to take

steps to provide line differential protection at their

respective ends on all 400 kV lines (except Gooty line)

emanating from Nellore Pooling Station, and furnish

an action plan to implement the same.

57/II/9 Tripping of 400 kV Nellore

(PG) - NPS line-1, 400 kV

Krishnapatnam-Nellore (AP)

lines -1&2 and 400kV NPS -

MEPL line

18-07-2016

at 19:05 hrs

APTRANSCO mail dated on 20-12-2016:

Issue was addressed to the concerned for necessary action.

APTRANSCO mail dated on 24-05-2017:

Meeting was conducted and the relays procurement for all the loctions is under

progress.

APTRANSCO mail dated on 20-10-2017 & 22.11.2017:

Relays procurement for all the locations is under progress.

APTRANSCO Mail dated 15.12.2017:

Technical bids opened. PQ evaluation under progress . Price bids expected to open in

next week.

PGCIL (SR-I) Mail dated 15.12.2017:

LDP relays procurement is under process. Procurement will be completed by Feb-

2018. TPCIL has to give written confirmation for LDP relay procurement. For want

of written confirmation from TPCIL, PGCIL approving authority has withheld the

LDP proposal.


PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL to

complete procurement of LDP relays. To this, PCSC forum asked TPCIL to submit



complete the work by FEbruary, 2018.





asked all stakeholders to ensure & comply with the same.

Triggering incident was snapping of Y phase conductor

in 400kV Nellore (PG) - NPS line-1. Distance relay at

Krishnapatnam end over-reached in Zone-1, and

resulted in tripping of 400kV Krishnapatnam – Nellore

(AP) lines - 1&2 from Krishnapatnam end. Distance

relay at MEPL over-reached and resulted in tripping of

MEPL-NPS line from MEPL end.

PGCIL (SR-I), TPCIL, MEPL, SEL, SGPL,

APTRANSCO, APGENCO and SDSTPS to

implement line differential protection on all 400 kV

transmission lines (of length less than 50 km)

emanating from Nellore PS, Nellore (PG) SS, and

Nellore (AP) SS. [It may be noted here that the cut-off

length of 50 km has been specified with a view to

exclude only long transmission lines].

APGENCO/

PGCIL(SR-I)/

TPCIL/MEPL/SEL/

SGPL/ APTRANSCO

Pending

Annexure-II

Page 2 of 30


ABB make LDP relays for Main-1 protection were delivered earlier and schneider

make LDP relays for Main-2 protection are delivered in this week.


ABB & SCHNEIDER Relays are drawn and available at site. To be commissioned

in coordination with the Alstom (Area) engineers who implemented SAS.


PGCIL(SR-1): PO placed on M/s GE & TD India Ltd on 24.09.2018. Supply of

relays will be completed by Jan'2019 and commissioning by Mar'19

APTRANSCO MAIL DATED 22.01.2019:

The relays are yet to be commissioned.

APTRANSCO mail dated 15.03.2019:

Commissioning of LDP relays scheduled in the month of April 2019.


Schnider make P546 LDP relays commissioned in place of Main-1 relays at Nellore

end for 400KV Krishnapatnam feeder on 26/03/19 and for feeder-2 on 27/03/19.

ABB make RED670 relays yet to be commissined in place of Main-2 relays.


PGCIL-SR1: LDP relays (Main-1) commissioned in 400kV NPS-TPCIL-1 Line

during opportunity shutdown. NPS-NCC D/C & NPS-TPCIl D/C lines LDP relay

retrofitting planned in June & July -2019.

In 154th OCC meeting SRLDC/SRPC has advised to re-schedule LDP

commissioning tentatively to Sep/Oct’2019.


ABB make RED670 relays testing is under process and will be commissioned in

place of Main-2 relays for Krishnapatnam-1&2 feeders by 30.06.2019 at 400KV

Manubolu SS.

64/I/1 Complete outage of North

Chennai TPS STG-2

24-04-2017

at 21:02hrs

Tripping of evacuating lines due to fault led to tripping

of Units


Chennai TPS STG-2

25-04-2017

at 18:27hrs


of Unit


Chennai TPS STG-2

26-03-2017

at 21:09 hrs


of running Unit at NCTPS Stg-2

PendingTANTRANSCO and PGCIL (SR-II) to take steps to

complete insulator replacement works on the 400 kV

lines owned by them in Chennai area within 3 months.

TANTRANSCO/

PGCIL(SR-II)





MEPL line

18-07-2016

at 19:05 hrs






relay at MEPL over-reached and resulted in tripping of

MEPL-NPS line from MEPL end.

PGCIL (SR-I), TPCIL, MEPL, SEL, SGPL,

APTRANSCO, APGENCO and SDSTPS to

implement line differential protection on all 400 kV

transmission lines (of length less than 50 km)

emanating from Nellore PS, Nellore (PG) SS, and

Nellore (AP) SS. [It may be noted here that the cut-off

length of 50 km has been specified with a view to

exclude only long transmission lines].

APGENCO/

PGCIL(SR-I)/

TPCIL/MEPL/SEL/

SGPL/ APTRANSCO

Pending

Status received vide TANTRANSCO mail dated 15-06-2017 & 04.08.2017 &

18.09.2017 & 12-12-2017:

1. All the Porcelain insulators of 400kV NCTPS-II - Vallur feeders-1&2 were

replaced with Polymer insulators by 20.05.2017. -----Completed

2. Existing Porcelain insulators of all other 400kV feeders are being replaced with

Polymer insulators in a phased manner.

--- Pending

PGCIL (SR-II) Mail dated 11-12-2017:

Pertaining to POWERGRID all the porceleing insulators in the polluted streches has

been completed. - Completed.


TANTRANSCO informed that a total of 597 insulators ahd alreeady been replaced,

and the total replacement would take another 9-month period.

In this regard, TANTRANSCO was asked to furnish detailed plan of action regarding

replacement of insulators on all 400 kV lines owned by them in Chennai area.

TANTRANSCO MAIL DATED 25.01.2018:

Existing Porcelain insulators of all other 400kV feeders are being replaced with

Polymer insulators in a phased manner. Timeline: Sep-2018. Detailed plan of action

will be submitted.



Polymer insulators in a phased manner. Timeline: Sep-2018.

Annexure-II

Page 3 of 30




will be submitted.




will be submitted.



Polymer insulators in a phased manner. Timeline: Sep-2018.



Polymer insulators in a phased manner. Timeline: Dec-2018.


1.Replacement of porcelain insulators with Polymer insulator for 4 Km radius from

NCTPS.2 in 400kV SVCM & Alamathy feeders were completed.

2. Further, Procurement under progress for replacement of 230kV and 110 kV TANTRANSCO MAIL DATED 23.01.2019:

Time Line requested upto June 2019


Replacement of porcelain insulators with Polymer insulator for 4 Km radius ( in

Chennai area) from NCTPS.2 in 400kV SVCM & Alamathy feeders were completed.

NTPC mail dated 07.12.2017:

1. High set DEFR on 220 KV lines is disabled ----Completed

2. ---- Pending


TSTRANSCO informed that the works are under progress, and are targeted to be

completed in 3 months time.

TSTRANSCO MAIL DATED 20.01.2018:

Line Differential Protection will be provided within 3 months i.e., by end of March,

2018.


Line Differential Protection relays are under procurement and will be provided by end

of May, 2018.


Line Differential relays will be supplied to site by manufacturer by end of May, 2018

and erection will be completed by end of June, 2018.


Inspection of the relays is completed and the relays are received at stores. Relays are

to be drawn and commissioned. Work is expected to be completed by end of


Relays will be commissioned by end of February, 2019.


Replacement of porcelain insulators with Polymer insulator for 4 Km radius ( in

Chennai area) from NCTPS.2 in 400kV SVCM & Alamathy feeders were completed.

TSTRANSCO mail dated 22.06.2019:

2. Relay erection work is under progress and will be completed by end of July, 2019.

Pending

NTPC-Ramagundam/

TSTRANSCO

Pending66/ II/ 10 Tripping of 400/ 220 kV

ICT’s – 3 & 4 at

Ramagundam STPS

TANTRANSCO and PGCIL (SR-II) to take steps to

complete insulator replacement works on the 400 kV

lines owned by them in Chennai area within 3 months.

TANTRANSCO/

PGCIL(SR-II)

11-06-2017

at 19:46hrs

Triggering incident was failure of 220 kV

B-phase LA in ICT-3 LV extension feeder (220KV

line-2) at Malayalapalli substation

1. NTPC to disable high-set of DEFR on the 220 kV

lines emanating from their Ramagundam STPS.

2. NTPC/ TSTRANSCO to provide Line Differential

Protection (with or without pilot) on 220 kV

Ramagundam – Malayalapalli lines – 1 & 2 & 3.

Annexure-II

Page 4 of 30

69/I/2 Complete outage of 400kV

TPCIL station

30-10-2017 at

21:37 hrs

400kV TPCIL - Nellore line-1 got tripped at TPCIL

end during failure of LA of Station Transformer-2 at

TPCIL. Running Units at TPCIL got tripped due to loss

of evacuating line. 400kV TPCIL - Nellore PS line-2

was under emergency shutdown

1. TPCIL to configure DEF protection such that it

remains in blocked condition as long as Distance

Protection is active, and becomes active only when

distance protection does not pickup.

2.PGCIL (SR-I) to ensure healthiness of Carrier

communication, and the set PUP mode of carrier aided

scheme operates reliably on TPCIL lines 1 & 2.

TPCIL/

PGCIL (SR-I)


PGCIL (SR-I) informed that they are waiting for written confirmation from TPCIL to

complete procurement of LDP relays. To this, PCSC forum asked TPCIL to submit



complete the work by February, 2018.





asked all stakeholders to ensure & comply with the same.


2. PGCI(SR1) procuring LDP relays for retrofitting of Main-1&2 distance relays.


week.


2. PO placed on M/s GE & TD India Ltd on 24.09.2018. Supply of relays will be

completed by Jan'2019 and commissioning by Mar'19.

Review Meeting on 20.12.2018 & 27.06.2019:

Pending

APTRANSCO maild ated 30.01.2018:

1. Pending...

2.A/R scheme on 400kV Kurnool (PGCIL) feeder-2 will be checked after getting LC.

APTRANSCO maild ated 24.04.2018 & 24.05.2018 & 26.06.2018:

1. Pending...

2. B Ph auxilary trip relay is found defective. The same is to be replaced by M/S

PGCIL. Ii) PD relay event is configured in the EL as per the recommendation.


1. ---Pending

2. PGCIl(SR-1): B-Ph auxiliary relay problem rectified at Narnoor end by replacing

relay contact. ---Completed


1) Bays and lines pertains to PGCIL .

2) ---Completed.


1) PO placed on M/s GE & TD India Ltd on 24.09.2018. Supply of relays will be

completed by Jan'2019.


Pending [with PGCIL (SR-I)]


PGCIL(SR-1):

This issue of retrofitiing of distance relays with LDP relays in Kurnool(PG) –

Kurnool(AP) D/C lines has been discussed with our management. Our management is

seeking approval for the same. You are requested to takeup this LDP issue in next

TCC meeting. APTRANSCO maild ated 15.12.2017:

APTRANSCO would extend support and requirements if any ,for the rectification

proposed by KPTCL.


It was noted that the original Gooty - Lingapur line got LILOed at BTPS, Alipura,

and Ragulapadu. It was also noted that Phase Discrepancy is being observed in

Ragulapadu - Alipira section only. When enquired about the same, KPTCL informed

that they would examine the issue in detail, and would inform the action lan proposed

by next PCSC-71 meeting. On this, APTRANSCO was also asked to render all help

required from their side to KPTCL.

APTRANSCO maild dated 30.01.2018:

APTransco world extend required support .

APTRANSCO maild dated 24.04.2018 & 24.05.2018 & 26.06.2018:

AP Transco would extend required support for attending, phase discrepancy issue in

ragulapadu-Alipura line by KPTCL.


To be attended by KPTCL as discussed in 75th PCSC meeting.


Phase mis match issue is to be sorted out jointly by KPTCL/ APTRANSCO/ KPCL.

Tripping of 400 kV

Kurnool(PG) – Kurnool(AP)

line-2

APTRANSCO/

PGCIL (SR-I)

69/III/7 Tripping of 220 kV

Ragulapadu – Alipura line

12-10-2017 at

01:30 hrs

KPTCL and APTRANSCO to sort out issues relating

to incongruence in denoting R, Y, B phases of the

electric supply on their respective sides.

APTRANSCO/ KPTCL Pending

[with KPTCL ]

Pending [with

PGCIL (SR-I)]

69/III/3 02-10-2017 at

02:03 hrs

1) PGCIL (SR-I) and APTRANSCO to provide for

Line Differential Protection as both the Main

protections on 400 kV Kurnool (AP) – Kurnool (PG)

lines 1 & 2 lines.

2) APTRANSCO to furnish an action taken report

w.r.t. resolving A/R non-operation at Kurnool-AP end

for the subject trippings and configure EL for capturing

PDR operation at their 400 kV Kurnool-AP SS.

Line tripped on B-ph to ground fault. A/R was

unsuccessful at both Kurnool (AP) and Kurnool (PG)

ends.

Line tripped on B-Ph to earth fault. A/R was successful

at Regulapadu and breakers at Alipura end got tripped.

Annexure-II

Page 5 of 30

Review Meeting on 20.12.2018:

PCSC forum decided that concrete action in this respect to be initiated in 2 months by

KPTCL alongwith APTRANSCO.


Pending [with KPTCL ]


KPTCL informed that the work is expected to be completed by August 2019.

76/II/9 Tripping of 230 kV

Thiruvalam - Chittoor line

13-06-2018 at

18:55hrs

Y-phase to earth fault occurred in line. At 230 kV

Tiruvalam end, breaker was under lockout leading to

operation of LBB protection.

1) TANTRANSCO to provide double-bus operation at

their 230 kV Thiruvalam SS.

2) APTRANSCO to replace the existing static relays

with suitable numerical relays for various line

protections at their 220 kV Chittoor SS.

TANTRANSCO/

APTRANSCO

1) TANTRANSCO Mail dated 29.08.2018 & 11.09.2018:

Material supplied and work to be taken up ---Pending

2) APTRANSCO Mail dated 24.09.2018:

The static relays were replaced with Numerical relay on all 220 kV feeders at 220 kV

SS chittoor.---Completed

TANTRANSCO Mail dated 11.12.2018:

Due to space constraint, the equipments could not be erected.


In view of Tiruvalam being inter-state sustation, TANTRANSCO was asked to

prvodie double-bus operation at their 230 kV Tiruvalam SS.


Pending [with TANTRANSCO]

TANTRANSCO MAIL DATED 23.01.2019 & 19.03.2019:

Feasibility for providing hybrid breaker / shifting of bays will be studied & action

will be taken. Time upto Sep 2019


1. Bus segregation will be ensured by providing bus coupler bay by extending the

Pending [with

TANTRANSCO]


3). Nagzari-Bidnal PLCC link is healthy --- Completed.

1.--- Pending

2. --- Pending


1. & 3. Completed

2. Pending

KPCL mail dated 24-12-2018:

1) --- Completed

2) Proposal will be taken up for replacement of existing PZ1000 relays with new

version Numerical Line protection relays having IEC61850 shortly, after availing

necessary admnistrative approval...Pending

3) Completed

KPCL mail dated 23.01.2019:

1. Completed

2. Letter addressed to site to take up the proposal for replacement of PZ1000 line

distance relays.KPCL mail dated 23.03.2019:

1). COMPLETED


version Numerical Line protection relays having IEC61850. Prepration of

specification is under progress.

3) COMPLETED


1) & 3) Completed

2) Budgetary offer obtained for replacement of existing PZ1000 relays with new

version Numerical Line protection relays having IEC61850. Preparation of estimation

and specification is under progress.


1) & 3) Completed

2) Replacement of existing PZ1000 relays with new version Numerical Line

protection relays having IEC61850 is included in PSDF Phase-II DPR. Approval of

NLDC for DPR is awaited. Further, availing administrative approval for issue of NIT

for replacement of existing PZ1000 relays with new version Numerical Line

protection relays having IEC61850 and preparation of estimation and specification is

under progress.


220kV lines connected to Nagjheri PH got tripped due

to successive transient faults. Running Units #3 and #4

at Nagjheri got tripped on over frequency protection

operation due to loss of evacuating lines resulting in

complete outage of 220 kV Nagjheri. 220 kV Nagjheri

being the only source to 220kV Ambewadi station,

since 220kV Ambewadi Narendra line 1&2 were under

shutdown during antecedent condition, tripping of

Units at 220 kV Nagjheri resulted in the loss of supply

to 220 kV Ambewadi SS.

1. SLDC/KPTCL to be pro-active in issuing necessary

directions that help in expeditious restoration of the

tripped lines based on the prevailing conditions and

grid security.

2.KPCL to implement A/R enabled on all 220 kV lines

emanating from their 220 kV Nagjheri PH, with the

help of KPTCL, by December, 2018. In the event of

non-amenability of the existing PZ1000 relays in

providing A/R feature, KPCL shall take steps to

retrofit them with suitable relays that support A/R.

3. KPTCL to restore PLCC carrier communication on

220 kV Nagjheri – Bidnal line at the earliest

KPCL/ KPTCL Pending


Ragulapadu – Alipura line

12-10-2017 at

01:30 hrs

KPTCL and APTRANSCO to sort out issues relating

to incongruence in denoting R, Y, B phases of the

electric supply on their respective sides.

APTRANSCO/ KPTCL Pending

[with KPTCL ]

17-09-2018 at

14:37hrs

78/I/2 Complete outage of 220 kV

Nagjheri PH and 220/110 kV

Ambewadi Substation.

Line tripped on B-Ph to earth fault. A/R was successful

at Regulapadu and breakers at Alipura end got tripped.

Annexure-II

Page 6 of 30

78/II/16 Multiple trippings at 220kV

Nagjheri PH

31-08-2018

at 11:49 hrs

Triggering incident was B-E fault in 220 kV Nagjheri -

Ambewadi line-1. As per the information received,

after tripping of 220 kV Naghjeri - Ambewadi line-1,

220 kV Naghjeri Ambewadi line#2 got overloaded.

This resulted in the tripping of Nagjheri Generating

Units #3 and 6 on SPS operation. At the same time,

Unit #2 got tripped on REF operation.

1)KPTCL to examine the reasons for tripping of more

than one Unit (Units – 3 & 6) on SPS operation at

Nagjheri PH during subject trippings, and furnish a

report on the same along with remedial action taken to

PCSC forum.

2)KPCL to employ a suitable time delay of 50 – 60

msec in operation of REF protection for the GT of Unit-

2 at their Nagjheri PH.

KPTCL/ KPCL Review Meeting on 20.12.2018:

1. KPTCL I formed that SPS scheme finalisation shall be completed in one month

time --- Pending

KPCL mail dated 24-12-2018:

2) Time delay of operation is not changed. However, the external NCT is used for

REF protection against earlier internal NCT for REF, to avoid tripping due to

malopration --- Completed.


1) It shall be reviewd and Implemented by KPCL in coordination with KPTCL.

2)....Completed.


1) It shall be reviewd and Implemented by KPTCL in coordination with KPCL.

KPCL mail dated 10.05.2019 & 25.06.2019:

1) Letter addressed to KPTCL RT dated: 25.03.2019 for review and implementation

of SPS at NPH. Reply is awaited.


1. KPTCL informed that Nagjheri SPS has to be studied in the event of configuration

changes and outcome of the same will be intimated soon .

Pending

TANTRANSCO Mail dated 11.12.2018:

1. TANTRANSCO: Estimate sanctioned for replacement of defective isolator status

feedback. Work under progress. ......Pending

2.Earth value of 110kV earthmat has been improved & 230kV side earthmat work

under progress. Lightning mask earthing renovation under execution............Pending

3.......Pending


Relays settings reviewed and need to be revised due to change of line length DR &

EL's of Main-1 (P444) relay configured properly. Main-2 (D60) relay to be

configured.


1 & 2). TANTRANSCO informed that Work will be completed by March 2019.

3. APTRANSCO informed that work will be completed by February 2019.


Collecting the details of adjacent feeders connected to Gummadipudi for computing

revised relay settings.


Isolator status will be ensured by March 2019APTRANSCO mail dated 15.03.2019:

3. Revised relay settings were implemented on 16/02/2019 ---Completed


New 230kV isolators have been allotted for replacement of defective isolators. Hence

time line requested upto June.2019.


1. New 230kV isolators have been allotted for replacement of defective isolators.

Hence time line requested upto Sep.2019.


1. New 230kV isolators have been allotted for replacement of defective isolators.

Hence time line requested upto Sep.2019.

2. & 3. Completed81/IV/3 Tripping of 400 kV

Warangal - Bhoopalapalli

line-2

15-12-2018 at

20:42 hrs

Line tripped at Bhoopalapalli end only and was holding

from warangal s/s. FIR, DR and EL of Bhoopalapally

were not furnished.

For the line under consideration, the following shall be

carried out by TSGENCO in coordination with PGCIL

(SR-I):

(i) End-to-end communication for DT/ permissive &

other signals may be ensured by testing at both the

ends.

(ii) Healthiness of PLCC system components

(hardware and software) at both ends shall be checked

and faulty components shall be repaired/ replaced.

TSGENCO/ PGCIL (SR-

I)


PGCIL-SR1: Presently WGL-Bhopalapalli-2 line PLCC Ch-1 is unhealthy same was

informed to TSGENCO for rectification. The Ch-1 is out of service from last 50 days

onwards. Both ends PLCC belongs to TSGENCO

TSGENCO mail dated 24.06.2019:

TSGENCO is cordinating with TSTRANSCO for testing of End-to-End

communication for DT/permissive & other signals; checking of Healthiness of PLCC

system components and also for replacing of faulty components .


TSGENCO informed that PLCC has to be replaced and will be done by December

2019.

Pending [with

TSGENCO]

TANTRANSCO/

APTRANSCO

05-10-2018 at

00:42 hrs

Complete outage of 230/ 110

kV Gummidipoondi

Substation

1) TANTRANSCO to take steps to implement multi-

bus, multi-zone operation (Double-bus operation) at

their 230 kV Gummidipooindi SS by December,

22018.

2) TANTRANSCO to check if the Gummidipoondi

substation is adequately protected from lightning-

strokes by providing requisite no. of lightning masts

and/ or earth-wire caging.

3) APTRANSCO was asked to verify & correct the

settings employed for distance protection at Sullurpeta

and configure DR’s & EL’s of all Protection Relays at

their Supllurpet SS properly for recording only the

mandated protections & digital signals.

Pending [with

TANTRANSCO]

79/I/2 Triggering incident was B-phase fault at 230kV

Gummidipoondi Substation due to which 230kV Bus-1

Bus-bar protection operated. 230kV Gummidipoondi

Station was under single bus operation, hence

operation of Bus-bar protection resulted in tripping of

all connected elements.

Annexure-II

Page 7 of 30


Veeranam substation of

TANTRANSCO

11-03-2019

at 00:55Hrs

Triggering incident was Y-phase CT blast in 230kV

Tirunelvelli (Abhishekpatty) – Veeranam Ckt-1.

230kV Trirunelvelli – Veeranam Ckt-1 and 2 tripped.

Two faults were observed from the PMU plot. During

the second fault, delayed fault clearance of 400ms was

observed. As reported, other connected feeders 230kV

Veeranam – Kodikur ckt-1&2 and 230kV Veeranam –

Kayathar tripped on Zone -2 protection.

1. TANTRANSCO is recommended to submit action

plan to provide Multi-Bus operation/ Hybrid breakers

at 230kV Veeranam SS with clear timelines.

2. TANTRANSCO to revise the distance zone settings

at Tiruneveli SS for 230kV Veeranam – Tirunelveli

line to overcome the problem of relay overreach and

share the same with SRPC.

3. TANTRANSCO to take definite measures ensure

the time synchronization of relays at Tirunelveli end.

4. TANTRANSCO to submit equipment failure report

of the failed CT to CEA.

TANTRANSCO TANTRANSCO MAIL DATED 13.06.2019:

1.Provision of bus coupler breaker is not feasible due to space constaint.

2&3. Tirunelveli end maintained by PGCIL.

4. Report will be sent.

Review meeting on 27.06.2019:

1.Provision of bus coupler breaker is not feasible due to space constaint.

2. Will be informed

3. Time synchronisation will be ensured.

4. Report will be sent.

Pending[TANTRA

NSCO & PGCIL-

SR-II]

83/I/3 Complete outage of

220kV/132kV

Chinakampalli Substation of

APTRANSCO

25-03-2019

at 04:13Hrs

Triggering incident was failure of B-ph CT of Bus

Coupler at 220kV Chinakampalli SS. Bus bar

protection of Bus-1 and Bus-2 operated resulting in the

tripping of all the connected elements at 220kV

Chinakampalli SS. 400kV/220kV ICT#1, 2 and 3 at

Cuddapah also got tripped during this event.

1. APTRANSCO is recommended to properly label the

digital signals of DR’s generated during fault.

2. APTRANSCO to submit equipment failure report of

the failed CT to CEA.

3. PGCIL (SR-I) is recommended to coordinate the

backup protection of ICT with other primary

protections in the interest of system reliability. PGCIL

(SR-I) is also informed to share the setting calculation

for pickup current of ICT highset operation and to raise

the high set pick up value for their ICT’s or to increase

the time delay of operation of highset of ICT Backup

protection.

APTRANSCO/ PGCIL

(SR-I)


1) The configuration of lables of digital signals of DR’s generated during fault will be

done by 30.06.2019

2) Equipment failure report submitted to SRPC protection wing on 18.06.2019--------

Completed

Pending


Hubli substation of KPTCL

and 220kV

Nagjheri Power station of

KPCL

10-04-2019

at 18:09Hrs

Y and B-phase earth isolator switch blades of 220kV

Hubli-Bidnal ckt-1, got closed due to failure of locking

mechanism during heavy wind and rain

conditionsresulting in bus fault. Bus bar protection

operated and all connected elements tripped. There was

1. KPTCL is recommended to revise the SPS at

Nagjheri, (to accommodate a new condition with high

flow and low time delay) in consultation with SRPC

and SRLDC.

2. KPCL in coordination with KPTCL is recommended

KPTCL/ KPCL KPCL mail dated 25.06.2019:

2) Carrier aided protection is enabled on all 220kV lines emanating from NPH

___Completed


Pending


GUTTUR - NARENDRA -1

10-03-2019 at

18:03hrs

Line tripped on operation of overvoltage stage-1

protection at Guttur end and DT received at Narendra

end. Voltages at Guttur end: Vr-254kV, Vy-252kV,

Vb-246kV. As per voltage grading, 400kV Guttur

Narendra line-2 should trip first.

PGCIL (SR-II) to submit action plan regarding

replacement of CT’s for 400Kv Guttur Narendra line -

1 at Guttur end. PGCIL (SR-II) to sort out the time

sync issues in DR and EL at Narendra end.

PGCIL (SR-II)/ KPTCL PGCIL (SR-I) mail dated 07.06.2019:

Line belongs to PGCIL(SR-2)


PGCIL(SR-II) informed that R & Y ph CVT replaced on 25.05.2019. Time

syncronisation has to be attended by KPTCL.

Pending

23-03-2019 at

04:41 hrs

24-03-2019 at

02:32 hrs

25-03-2019 at

01:19 hrs


NCTPS Generating Station

of TANGEDCO

18-05-2019 at

04:39 hr.

Triggering incident was Y phase to Earth fault in 220

kV NCTPS Tondiarpet line-2. Due to mal-operation of

LBB protection (of Tondiarpet line-2) at NCTPS end,

all the connected elements of bus zone-3 got tripped.

Due to loss of evacuating lines, running units at

NCTPS unit#1 and 2 got tripped.

1.TANTRANSCO may take immediate measures to

attend the problem in LBB wiring that is extending trip

during A/R within one month.

2. TANTRANSCO is recommended to send a detailed

report regarding the A/R status (availability

/enabling)on all lines emanating from 230kV NCTPS

GS and enable A/R in all lines emanating from 230kV

NCTPS GS.

3.TANGEDCO in coordination with TANTRANSCO

may take definite measures to ensure time

synchronization of all relays with GPS signal at

NCTPS end and remote ends at the earliest.

4. It was also suggested that possibility of backing

down of generation, in the event of unavailability of

many feeders, in particular when radial feeders only

are in service, may be looked at.

TANGEDCO/

TANTRANSCO

Yet to be informed Pending

APGENCO/

APTRANSCO


3. Line Insulator stacks were replaced with SRC insulators at location Nos.4,5,6 for

Krishanpatnam-1 on 26/03/2019 and Krishanpatnam-2 on 27/03/2019.--------------

Completed.


1. APGENCO representative did not attend the meeting. APGENCO is requested to

furnish the status at the earliest.

Pending [ with

APGENCO]

Tripping of 400kV

Krishnapatnam – Nellore ckt-

1

Feeder tripped due to severe tracking on line insulator

stacks.

1. APGENCO to inform PCSC forum the following:

Status of A/R in 400kV Krishnapattnam – Nellore

line-1 at Krishnapattanam end, if A/R is not enabled

APGENCO shall implement 1-ph ‘lead-follow’ A/R

scheme at Krishnapattanam.

The reason for tripping of Unit-2, along with the line

tripping on 24.03.2019.

2. APGENCO in consultation with APTRANSCO to

explore the possibility of providing Line Differential

Protection (LDP) for the line.

3. APTRANSCO is recommended to replace the

insulators of the line with polymer insulators.

83/II/17

Annexure-II

Page 8 of 30


NCTPS Generating Station

of TANGEDCO

19-05-2019 at

22:44 hr.

230kV lines connected to NCTPS got tripped due to

fault in lines. Running units#1,2 and 3 at 230kV

NCTPS also got tripped due to loss of evacuating lines.

1. TANGEDCO in coordination with TANTRANSCO

to take definite measures to ensure time

synchronization of all relays with GPS signal at

NCTPS end and remote ends at the earliest.

2.The PCSC noted frequent jumper cut/conductor snap

instances in the area, of late; accordingly, it was

suggested to have adequate condition monitoring and

preventive maintenance measures.

3.TANTRANSCO to communicate

(i) the schedule of replacement of balance porcelain

insulators with polymer insulators in evacuation lines

from NCTPS.

(ii) schedule of insulator washing

4.NCTPS /TANGEDCO to inform regarding house

load operation capability of Generators at NCTPS.

TANGEDCO/

TANTRANSCO


84/II/4 Tripping of 230kV Sulurupet-

Gumudipoondi line

11-04-2019 at

16:05 hr.

Triggering incident was B-N fault in 230kV

Gummudipoondi-NCTPS line. 230kV Sulurupet -

Gummudipoondi line tripped on operation of zone-2

distance protection at Sulurpet end and reverse zone

protection at Gummudipoondi end.

1.TANTRANSCO to check the resistive and reactive

reach settings of 230kV Gummudipoondi-NCTPS line

at Gummidipoondi end.

2. APTRANSCO to ensure time synchronization of

DR and EL at Sulurupet end. Also in coordination with

TANTRANSCO sort out the time synchronization

issue in 230kV Sulurupet-Gumudipoondi line.

3. TANTRANSCO to check the SOTF settings at

Gummidipoondi end for 230kV Gummudipoondi-

NCTPS line .

TANTRANSCO/

APTRANSCO


84/II/11 Tripping of 220 kV-

NAGARJUNASAGAR AP-

NAGARJUNASAGAR TS

line-2 & 3

17-04-2019 at 15:54 hr.Line -2 tripped due to B phase fault. 1. APTRANSCO in coordination with TSGENCO to

carry out end-to-end testing of PLCC channel and

ensure healthiness of the same. A report in this respect

to be given to SRPC.

2. APTRANSCO in coordination with TSGENCO to

ensure time synchronization of relays at both ends

APTRANSCO/

TSGENCO


84/II/19 Tripping of 400/220 kV ICT-

1 atCuddapah

03-05-2019 at

23:39 hr.

ICT-1 Tripped on operation of APTRANSCO 220 kV

Bus Bar relay (96 trip relay). Fault reported in 220 kV

Cudappah-Renigunta line

1. PGCIL (SR-I) to submit the high set settings of

ICT’s at Cuddapah. Since the static relay in which

high set is enabled has no provision to provide time

delay, ICT high set shall be enabled from numeric

relay and sufficient time delay shall be provided for

highset operation.

2.APTRANSCO to check the Busbar operation at 220

kV Cuddapah SS and submit a report regarding the

same.

3. PGCIl (SR-I) to inform the methodology adopted for

calculating high set settings of ICT’s. Also due to

changes in system configuration at Cuddapah in recent

future revision of set points shall be taken up.

PGCIL (SR-I)/

APTRANSCO


84/II/22 Tripping of 400kV

Khammam-Mamidapalli line-

1

09-05-2019 at

02:40 hr.

Line tripped on mal-operation of Reactor differential

protection and DT sent to Khammam.

TSTRANSCO in coordination with PGCIL (SR-I) to

ensure time synchronization of relays at Mamidapalli

end with Khammam end in 6 months’ time.

TSTRANSCO/ PGCIL

(SR-I)


84/II/29 Frequent tripping of 220 kV

KTPS –Lower Sileru line

01-05-2019 at

16:04 hr.

04-05-2019 at

14:48 hr.

05-05-2019 at

11:29 hr.

06-05-2019 at

13:14 hr.

09-05-2019

at13:58 hr.

12-05-2019

at11:10 hr.

15-05-2019

at21:05 hr.

26-05-2019

at15:36 hr.

29-05-2019

at21:26 hr.

B-N FAULT

B-N FAULT

B-N FAULT

B-N FAULT

R-N FAULT

R-B FAULT

R-B FAULT

B-N FAULT

R-B FAULT

It was noted that no representative of APGENCO

attended the meeting.

For the subject line, the following shall be carried out

by TSGENCO in co-ordination with APGENCO:

(i) End-to-end communication for DT/ permissive &

other signals may be ensured by testing at boththe

ends.

(ii) Healthiness of PLCC system components

(hardware and software) at both ends shall be checked

and faulty components shall be repaired/ replaced.

APGENCO in coordination with TSGENCO to

ensure frequent patrolling and proper maintenance of

ROW by attending all tree clearance issues.

APGENCO/

TSGENCO


Annexure-II

Page 9 of 30





MEPL line

18-07-2016

at 19:05 hrs






APGENCO to furnish a report on the remedial action

implemented w.r.t. overreaching of Krishnapatnam end

distance relays during the tripping of 400 kV Nellore

(PG) - NPS line-1

APGENCO Review Meeting dated 19.12.2017:

It was noted that no APGENCO representative had come to attend the meeting.

APGENCO Mail dated 19.12.2017:

Procurement of relays is under progress

Pending

74/II/21 Tripping of 400 KV Kalikiri

– RYTPP line-2

29-04-2018 at

19:29 hrs

Line tripped on operation of over-voltage protection at

RYTPP and Direct Trip receipt at Kalikiri. The correct

operation of over-voltage tripping could not be

validated as FIR, DR and EL of RYTPP and DR and

EL of Kalikiri were not furnished.

1). APGENCO to furnish detailed report on the

reasons for the tripping of the line including remedial

measures taken.

2). APGENCO to ensure that the OVR-settings

implemented at Rayalaseema TPP are as per the SRPC

provided settings issued vide letter dated 01.05.2018,

and confirm the same.

APGENCO Status received vide mail dated 25.09.2018:

2). OVR settinss incorporated as per the Lr.No. CE/IPC&PS/SP/13/

400KV -OVR -SRPC/VOL.OI/ D.No,2001333/ 18: Dt: 04.05.18 --- Completed


1). It was noted that no APGENCO representative had come to attend the

meeting --- Pending


1. APGENCO representative did not attend the meeting. APGENCO is

requested to furnish the status at the earliest.

Pending


Kalikiri and 400 kV RyTPP,

Stage-V station

16:08 hrs on

11-05-2018

Triggering incident was R-E fault in 400kV RyTPP-

Kalikiri Ckt-1. Auto reclose (A/ R) was successful at

Kalikiri end but didn’t operate at RyTPP end. This led

to tripping of running unit at RyTPP due to tripping of

evacuating line and complete outage of RYTPP. At the

same time 400kV Chittoor-Kalikiri lines - 1&2 got

tripped from Chittoor end on operation of Z3 (mal-

operation) resulting in loss of supply to Kalikiri

station.

APGENCO to ensure that A/R functionality

implemented on 400 kV RyTPP (Stage-V) – Kalikiri

lines – 1 & 2 at RyTPP (Stage-V) end is healthy and in

kept service.

APGENCO Status received vide mail dated 25.09.2018:

RTPP,(9taqe-lU end,iis healthy and kept in service. Hence it is requested to drop all

the ahove points.


It was noted that no APGENCO representative had come to attend the meeting

--- Pending



requested to furnish the status at the earliest.

Pending

79/III/8 Tripping of 400 kV RYTPP-

Kalikiri line-2

26-09-2018 at

21:13 hrs

Line tripped on B-N fault. Auto-reclose was successful

at Kalikiri and three phase trip at RYTPP due to A/R

lock-out.

APGENCO to furnish a detailed report on tripping

event bringing out reasons for A/R non-operation at

yTPP end on 400 kV RyTPP – Kalikiri line along with

remedial action taken to PCSC forum.

APGENCO Review Meeting dated 20.12.2018:

It was noted that no APGENCO representative had come to attend the meeting.



Pending

82/III/8 Tripping of 400kV VTPS-

SURYAPET-1

10-02-2019

at 13:20 hrs

B-phase to earth fault occurred in line. Auto-reclose

was successful at Suryapet and breakers got tripped at

VTPS end


attended PCSC-82 meeting. APGENCO to furnish a

detailed report on tripping event bringing out reasons

for A/R non-operation at VTPS end along with


APGENCO Review Meeting on 27.06.2019:



Pending

82/III/9 Tripping of 400kV VTPS-

SURYAPET-1

15-02-2019

at 14:36 hrs

B-phase to earth fault occurred in line. Auto-reclose

was successful at Suryapet and breakers got tripped at

VTPS end


attended PCSC-82 meeting. APGENCO to furnish a

detailed report on tripping event bringing out reasons

for A/R non-operation at VTPS end along with





Pending

83/II/20 Tripping of 220kV VTS-

Talapalli ckt-3 and

Generating Units#1,2,3,4,5

& 6 at VTS.

01-04-2019 at

22:58hrs

220kV VTS – Talapalli ckt-4 was under maintenance.

While restoring the feeder, 220kV VTS – Talapalli ckt-

3 tripped on Zone-1 distance protection due to B-N

fault. At the same tine VTS unit# 1 & 2 tripped on

Loss of fuel and Generators 3,4,5&6 tripped on

Generator Negative phase sequence protection.

1. APGENCO is recommended to revise the time

delay of Negative Phase sequence protection operation

in consultation with OEM.

2. APGENCO is also recommended to look into the

Overcurrent Protection settings of Buscoupler, so as to

reduce its time delay of operation in case of faults on

Transfer Bus.




Pending

Andhra Pradesh

Annexure-II

Page 10 of 30

83/III/8 Tripping of 400 kV VTPS -

Nellore

24-03-2019 at

12:46hrs

Feeder tripped on Y -N Fault. Auto reclose operated at

Nellore end but not operated at VTPS end.

APGENCO is recommended to submit a detailed

report regarding the reason for A/R being kept

disabled and the Remedial Measure taken for the same.




Pending

82/II/5 Tripping of 400 KV

Mahbubnagar – Uravakonda

line - 2

22-01-2019

at 18:53hrs

OV St-1 at Uravakonda end and DT was received at

Mahaboobnagar end. From DR, voltages observed are:

Vr-244kV, Vy-247kV and Vb-257kV. B-ph voltage is

found to be higher than R and Y phases.

APTRANSCO to furnish details regarding the reasons

for OVR tripping and also to sort out time sync issues

in coordination with TSTRANSCO.

APTRANSCO APTRANSCO mail dated 13.05.2019:

The Ratio test was conducted on B-Phae CVT and test results found

satisfactory.Loose connetions observed at CVT JB and same was rectified. The 3-

Phase voltages were found to be normal after charging the feeder


The Ratio test was conducted on B-Phase CVT and test results found satisfactory.

Pending


2 at Nellore

13-04-2019 at 12:18 hr.ICT tripped due to operation of Buchholz and PRV

protection

PGCIL (SR-I) is recommended to sent Equipment

failure report of the failed 400/220 kV ICT-2 at

Nellore to CEA

APTRANSCO Yet to be informed Pending

84/II/7 Tripping of 220 kV Vemagiri-

Duvva line and 400/220 kV

ICT-2 at Vemagiri

15-04-2019 at

06:02 hr.

Triggering incident was R-phase to ground fault in 220

kV Vemagiri - Duvva line. LBB of 220 kV Bus-2

operated resulting at Vemagiri.

APTRANSCO to check the wiring to Event logger

for CB status, since, inspite of R-ph CB wiring issue

and non-opening of the same, Main CB R-ph open

status is obtained in Eventlogger.


84/II/9 Tripping of 220kV Bus 2 and

connected elements at 220kV

Gazuawaka Substation.

17-04-2019 at 5:40 hr.Triggering incident was Y-phase to earth fault in

220kV Gazuwaka Bus-2. This resulted in tripping of

220 kV elements and 400/220 kV ICT-2

1. APTRANSCO to submit a detailed report

regarding the subject tripping at 220 kV Gazuawaka

Substation along with the remedial measures taken.

2. For all lines emanating from Gazuwaka SS, RTV

coating shall be taken up.


84/II/26 Tripping of 220 kV Bus-2 at

400/220 kV Talarichevu

25-05-2019 at

07:33 hr.

As reported, bus bar protection of 220 kV Bus-2 at

400/220 kV Talarichevu station operated due to

through fault. This resulted in tripping of all elements

connected to Bus-2.

APTRANSCO to submit a report regarding the Bus-2

BBP operation alongwith the remedial action

suggested by OEM.


84/IV/1 Tripping of 400kV

Khammmam – Kalpakka line

18-04-2019 at

14:49 hr.

DT received at Kalpakka end. APTRANSCO to submit report regarding the testing

of PLCC and rectification of PLCC related issues

carried out for 400kV Khammmam – Kalpakka line.


82/II/1 Tripping of 400kV KTPS VI-

KTPS VII

05-01-2019

at 10:17hrs

Line tripped at KTPS VI end due to suspected mal-

operation of over-voltage protection. Line was in

service from KTPS VII., BUS CVT secondary R

PHASE got grounded at KTPS VI

1) TSGENCO to configure OVR_start and

OVR_tripin EL at KTPS-VI end and sent a report after

completion of works related to DT communication

channel between KTPS-VI and KTPS-VII

TSGENCO TSGENCO mail dated 24.06.2019:

The issue is referred to M/s BHEL ( EPC vendor ) and the study on feasibility for

providing the communication with the existing available system is under process and

will be completed during the availability of next shutdown.


TSGENCO informed that the recommendations will be completed in September 2019

Pending

Telangana

Annexure-II

Page 11 of 30

83/III/6 Tripping of 400kV Julurpadu

- Manuguru line-2

14-03-2019 at

06:10:00

Triggering incident was R-ph fault in the line. At

Julurpadu end, fault was sensed in Zone-2 and carrier

was received but due to DT Receive from manuguru

end, A/r not operated and line got tripped. FIR, DR and

EL of Manuguru end are not available.

It was noted that no representative of TSGENCO

attended the meeting. TSGENCO is recommended to

submit a report on the tripping and to furnish

equipment failure report to CEA.

TSGENCO TSGENCO mail dated 24.06.2019:

FIR, DR and EL was uploaded in SRLDC website.Trip Report was also submitted.


TSGENCO informed that Equipment failure report will be sent to CEA.

Pending

84/II/28 Frequent tripping of 220 kV

KTPS –Nunna line

05-04-2019 at

12:55 hr. B-N

FAULT

15-04-2019 at

13:20 hr. Y-N

FAULT

16-04-2019 at

14:04 hr. B-N

FAULT

22-04-2019 at

14:13 hr. R-N

FAULT

23-04-2019 at

13:31 hr. R-N

FAULT

04-05-2019 at

14:40 hr. B-N

FAULT

09-05-2019 at

14:31 hr. B-N

FAULT

05-05-2019 at

13:03 hr. B-N

In 155thOCC meeting of SRPC, APTRANSCO

informed that the tripping was due to clearance issues

in the ROW caused by mango tree. It was cleared and

issue was rectified. However, frequent tripping of line

is still persistent.

1. TSGENCO to check the non-operation of carrier

aided trip, when fault is detected at KTPS end in Z-2

and carrier is also received, and submit a report

regarding the same.

2. TSGENCO and APTRANSCO to ensure that

ROW is cleared periodically.

3.APTRANSCO & TSGENCO may consider raising

the height of towers if the line is planned to be used in

future.

4.TSGENCO to consider replacement of old

pneumatic CB’s at KTPS if 220kV KTPS- Nunna line

is planned to be used in future.

TSGENCO Yet to be informed Pending


2 at Gajwel

11-04-2018 at

5:50 hrs

400/220 kV ICT-2 at Gajwel tripped on mal-operation

of Buchholtz relay.

1). TSTRANSCO was asked to keep the ICT and its

mechanical protections under observation for detecting

any slippages.

2). TSTRANSCO was also asked to configure

capturing of mechanical protections of ICT’s in the

respective relay’s/ station’s event logger.

TSTRANSCO TSTRANSCO mail dated 20.06.2018:

1. Mechanical protections of ICTs is under observation. --- Completed

2.New relays are available at site and will be commissioned by 2nd week of August-

2018. The mechanical protection of ICTs will be configured in the new relays ----

Pending


2. New relays will be commissioned by end of November-2018 and the Over Voltage

settings will be implemented after commissioning in new relays ----Pending


2. New relays will be commissioned by end of January-2019 and the mechanical

protections of ICTs will be configured in the new relays ----Pending

Pending

84/II/1 Tripping of 400kV Srisailam-

Dindi line-1 and 400kV

Mamidapalli-Dindi line-1

06-04-2019 at

17:39 hr.

400kV Mamidapally Dindi line-1 tripped on R-phase

to earth fault. 400kV Srisailam-Dindi line-1 tripped on

operation of cable differential protection at Srisailam

and direct trip was sent to Dindi.

1.TSTRANSCO to ensure time synchronization of DR

and EL at Mamidapalli end and Dindi end. Also in

coordination with TSGENCO sort out the time

synchronization issue in 400kV Srisailam – Dindi line-

1. 2.TSTRANSCO to ensure that A/R dead-time

is maintained as 1 sec uniformly at all Stations.

TSTRANSCO Yet to be informed Pending


2 and 3 at Dichipalli

Substation

22-04-2019 at

17:22 hr.

ICT#2 and 3 got tripped on suspected mal-operation of

LV earth fault relay during fault in 220 kV Dichpally-

Medaram feeder

1 .TSTRANSCO to ensure directional settings for ICT

earth fault protection and to ensure coordination

between line and ICT DEF protection.

2.TSTRANSCO to investigate the reason for non-

operation of LBB protection of 220 kVDichpally-

Medaram line while breaker lockout at Dichipalli SS

occurred.

3. TSTRANSCO to perform condition monitoring of

CB’s regularly to ensure sufficient air pressure for

proper CB operation.


84/II/27 Multiple tripping at 220 kV

Ghanapur station

27-05-2019 at

02:04 hr.

Triggering incident was failure of B-phase CT of bus

coupler of Bus-2. Bus bar protection of 220 kV Bus-2

operated resulting in tripping of all elements connected

to Bus-2.

1.TSTRANSCO is recommended to submit

Equipment failure report to CEA regarding the blast

CT.

2.TSTRANSCO to inform if any old CTs exist in

Ghanapur SS and ensure healthiness of the same to


Annexure-II

Page 12 of 30

84/III/4 Tripping of 400kV

Uravakonda - Veltoor ckt-1

13-04-2019 at

18:36 hr.

Y-phase to ground fault. Auto reclose didnot operate at

Veltoor end due to maloperation of STUB protection

TSTRANSCO to submit a report regarding the error

in PSL logic that led to the subject tripping along with

Remedial Measures taken.

TSTRANSCO to submit a report after checking mal-

operation of STUB protection on P444 relay.


TSGENCO mail dated 26.03.2019

Testing & commissioning of Line Differential Protection (LDP)relays were completed

for both Main-1 & 2 relays for Jurala PH- Jurala SS Feeder-1. For Jurala PH- Jurala

SS Feeder-2 retrofitting testing & commissioning of LDP relays for both Main-1

(RED 670) and Main-2 (MICPM P546) were completed except communication

establishment between both ends for Jurala SS Feeder-2 MICOM P546 relay.

Mail received on 21-10-2015:

1) Anti-pumping contactors of all the nine 220KV Lines are in circuit and tested

periodically during AOH works of lines along with other protections.

2) Completed.

3) Possibility to use both the 220kV buses as main bus under normal operation is

under review.

Mail recieved on 23-11-2015:

1) Completed

3) Two bus operation for 220kV buses : In place of existing CT switching relays,

High speed manual heavy duty change over switch of sufficient current capacity will

be retrofitted to all feeders at 220kV station and same will be operated manually

during changeover of feeder by one bus to the other and this arrangement may Status received vide KPCL mail dated 14.12.2017:

3) DPR for implementation of Two Bus operation for 220kV bus system has been

prepared and proposal is placed for funds from PSDF. After the approval of the DPR,

the work is proposed to be taken up.


3) KPCL informed that DPR for implementation of Two Bus operation for 220kV bus

system has been prepared and proposal is placed for funds from PSDF. After the

approval of the DPR, the work is proposed to be taken up. Time frame requested for

is 2 yrs.


3) Work proposed to be taken up under PSDF. Approval from Nodal agency is

awaited. However, arrangements have been made to issue NIT.


KPCL informed that Tender would be floated in 1 month and work would be

completed in 2 years.


Tender would be floated in 1 month and work would be completed in 2 years.

46/II/21 Trippings at 220kV Raichur

TPS

07-06-2015 at

01:35 hrs

1. KPCL to check the operation of anti-pumping relay

on 220 kV side and keep it in healthy condition.

2. KPCL to provide manual reset to the 220 kV side

master trip relay.

3. KPCL to use both the 220 kV buses as main buses

under normal operation, and should go for single bus

operation only during emergencies.

KPCL Pending

TSGENCO/

TSTRANSCO

Provision of line differential protection for Jurala line 1 & 2 (line length-1.45 KM) feeders at 220 kV Jurala HPS

[Carry-Over from Protection Audit Recommendations]

The issue was discussed in PCSC-58 meeting held on 18.10.2016, when PCSC forum

agreed to de-link the implementation of the Item from the scope of Protection Audit

Recommendations (PAR), and pursue it as part of PCSC Recommendations.

TSGENCO mail dated 30-05-2017

Procurement of Differential Protection relays is under process and the work will be

completed by the end of November 2017.

TSGENCO mail dated 18-09-2017

Procurement of Line Differential Protection Relays is under process and the work will

be completed by the end of January 2018.


TSGENCO informed that they are in constant touch with TSTRANSCO in this

regard, and hope to implement LDP by February, 2018.

TSTRANSCO informed that procurement of LDP relays is under progress, and

assured that LDP would be implemented in 3-months time.

TSTRANSCO MAIL DATED ON 20-01-2018:

The matter is being coordinated with TSGENCO.

Pending

Karnataka

PAR/

PCSC-58

Annexure-II

Page 13 of 30


Arrangements have been made to issue NIT and Tender for the work proposed to be

floated during May- 2019.


NIT will be issued during May- 2019.


1. & 2. Completed

3) Preparation of technical specification is in progress. NIT will be issued during July-

2019.


KPCL informed that timeline for completion of work is December 2019.

Status received vide KPCL mail dated 10.07.2017:

1. (ii) Hot line water washing stopped and off line water washing is carried out

whenever the 400 KV Unit or line is under tripped condition / Shutdown condition. ---

Completed

1. (iii) Silicon coating for Unit#8 main & tie breakers carried out in Sep'16 and same

is under observation. Till today in order and good condition. For remaining breakers,

since it is big order, approval for the same is under process. --- Pending

2. Static / Electromechanical relays are existing in all 1 to 7 units. Breaker flash over

protection feature will be enabled (if available) in the numerical relays which will be

retrofitted in phased manner during R&M works.


1.(i) --- Pending

1. (ii) Hot line water washing stopped and off line water washing is carried out

whenever the 400 KV Unit or line is under tripped condition / Shutdown condition. ---

Completed

1. (iii) Silicon coating for Unit#8 main & tie breakers carried out in Sep'16 and same

is under observation. Till today in order and good condition. For remaining breakers,

since it is big order, approval for the same is under process --- PendingReview Meeting dated 19.12.2017:

1 (iii) As upgradation of 400kV switchyard equip's to be taken under PSDF funds,

Silicon rubber coating for breakers is deffered till then. --- Pending

2. Replacement by Num relay for Units - 5,6 & 7 completed in the month of Oct-

2017. Main-I is Seimens make and Main-II is ABB make. --- Pending


2. Replacement of Numerical relays for Units-5, 6 & 7 have been completed.

Referred to OEM for providing the Breaker flashover protection for all the breakers.KPCL mail dated 23.03.2019:

1) (i) & (iii)- Arrangements have been made to issue NIT and Tender for the work

proposed to be floated during May- 2019.

2) Reply is awaiting from OEM to implement the Breaker flash over protection in the

Numerical relays in 400KV station. & Being discussed with other utilities.

It is requested to furnish Necessary logic and settings to implement the breaker

flashover protection


1) (i) & (iii)- NIT floated on 01.03.2019



It is requested that SRPC may suggest/furnish reference of necessary logic and

settings to implement the breaker flashover protection.


1) (i) & (iii)- NIT floated on 01.03.2019. Cover-I opened. Technical evaluation is in

progress. Approval from Nodal Agency is awaited.



It is requested that SRPC may suggest/furnish referenc of necessary logic and

46/II/21 Trippings at 220kV Raichur

TPS

07-06-2015 at

01:35 hrs

1. KPCL to check the operation of anti-pumping relay

on 220 kV side and keep it in healthy condition.

2. KPCL to provide manual reset to the 220 kV side

master trip relay.

3. KPCL to use both the 220 kV buses as main buses

under normal operation, and should go for single bus

operation only during emergencies.

KPCL Pending

54/II/9 PendingKPCL 1.KPCL to undertake the following remedial measures

to avoid breaker flashovers:

(i) Replacing all porcelain insulators with composite

insulators

(ii) Carrying out hot-line water washing of all

insulators on regular basis.

(iii) Applying Room Temperature Vulcanizing (RTV)

Silicone high voltage insulator coatings to all bus-

connected ceramic insulators of equipment like CT,

PT, CB, Isolators etc.

2.KPCL to take steps to provide dedicated breaker

flashover protection to all breakers at Raichur TPS at

the earliest.

Y-ph Pole of Tie-breaker of Unit-4 at RTPS failed.

Unit-4 got tripped on operation of Generator

Differential, Reverse power & LBB protection.

Operation of LBB protection led to tripping of BUS-2

at RTPS

13-04-2016 at

21:12 hrs

Tripping of 400kV Raichur

TPS

Bus-2

Annexure-II

Page 14 of 30


SRPC informed that referenc of necessary logic and settings to implement the breaker

flashover protection will be shared soon.

54/II/13 Tripping of Units at 220 kV

Raichur TPS

15-04-2016 at

15:36 hrs

During testing of retrofitted distance protection in

400kV Raichur-2 feeder, LBB protection trip DC got

extended to Bus trip. This resulted in tripping of 220kV

bus at RTPS and all connected 220 kV elements. Unit-

4 which is connected to 400 kV Bus got tripped due to

tripping of Station Utility Transformer that is

connected 220 kV bus

In view of the availability of two buses along with

healthy bus-coupler at 220 kV RTPS, KPCL is

recommended to put in service the double-bus

operation at 220 kV RTPS by suitably distributing

loads within 15 days.

KPCL Status received vide KPCL mail dated 10.07.2017 & 14.12.2017:

Two Bus operation for 220kV bus is being carried out whenever required. However

scheme for tripping of one bus during LBB/fault and maintaining the other bus intact

by tripping B/C breaker will be taken up in R&M works.


3) KPCL informed that DPR for implementation of Two Bus operation for 220kV bus

system has been prepared and proposal is placed for funds from PSDF. After the

approval of the DPR, the work is proposed to be taken up. Time frame requested is 2

yrs.

KPCL mail dated 20.12.2018 & 23.01.2019:

Work proposed to be taken up under PSDF. Approval from Nodal agency is awaited.

Pending Timeline?


1. All logics checked and found normal. LBB timing checked and found 200msec as

per KPTCL MRT recommendation. - Completed

2. Work Under Progress ---- Pending

3. New GPS System commissioned along with new numerical and synchronised with

GPS system - Complied

4. Work Under Progress ---- Pending

Status received vide mail dated 14.12.2017:

1),3),4) Completed

2. Auto Start of DG set is taken up --- Pending


2. KPCL informed that for AMF of DG, Scheme prepared & material procurement

under process. The AMF scheme will be implemented in January 2018. --- Pending

3. The GPS system commissioned on Nov 2016 & all the numarical relay time

synchronised with GPS ---- Completed


AMF panel procurement under progress.

KPCL mail dated 20.1.2.2018:

2. AMF scheme implementation is included in the work ''Replacement common

auxiliary panel with latest technology SCADA compatibility system'' . Availing Review Meeting on 21.12.2018:

KPCL informed that Tender for the work would be floated by January 2019 and work

would be completed in 1 year.


1) Completed.

2) Tender for the work would be floated by February 2019 and work would be

completed in 1 year....Pending

3) Completed.

4) Tender for the work would be floated by Feb, 2019, and work would be completed

in 1 year....Pending

KPCL mail dated 23.03.2019:Review meeting on 27.06.2019:

.1 & 3) Completed.

4) Tender published on 21.06.2019 and time line in June 2020.

2. tender has to be issued. Timeline requested upto December 2020.

69/II/8 Tripping of 220 kV Kaiga-

Kadra line-1

06-10-2017 at

22:22 hrs

While de-synchronising of Unit-2, B-phase pole of

GCB did not open and pole descrepancy relay

operated. Hence all 220KV lines CB hand tripped.

KPCL to take steps to replace the existing static

protection relays for Generator Units and Generating

Transformers (GT’s) with suitable Numerical relays at

their 220 kV Kadra PH.

KPCL Status received vide mail dated 25.07.2018:

Numerical Generator protection relay replacement proposed to be taken up alongwith

SCADA work.


Will be taken up along with SCADA work. NIT to be issued on Jan-2019


Pending

54/II/9

Timeline?PendingKPCL1) KPCL to check settings of LBB protection in all

relays from which it was implemented, and ensure that

their configuration, logic, and timing are in order at

their 220 kV Kadra PH.

2) KPCL to furnish details regarding the existing LT

auxiliary supply arrangement at their 220 kV Kadra

PH, and take steps to provide a suitable Auto-Main-

Fail (AMF) panel for DG set to effect its auto-starting

in case of failure of LT supply.

3) KPCL to ensure time-sync of all relays (DR’s &

EL’s) with GPS at their 220 kV Kadra PH.

4) KPCL to provide stand-alone Event Logger at their

220 kV Nagjheri PH.

LBB of 220kV Kodasalli breaker at Kadra end got

operated which resulted in tripping of Bus at Kadra

and in turn led to tripping of all elements

06-09-2016

at 14:40 hrs

Complete outage of 220 kV

Kadra power station of

KPCL

58/I/3

(GD)

PendingKPCL 1.KPCL to undertake the following remedial measures

to avoid breaker flashovers:

(i) Replacing all porcelain insulators with composite

insulators

(ii) Carrying out hot-line water washing of all

insulators on regular basis.

(iii) Applying Room Temperature Vulcanizing (RTV)

Silicone high voltage insulator coatings to all bus-

connected ceramic insulators of equipment like CT,

PT, CB, Isolators etc.

2.KPCL to take steps to provide dedicated breaker

flashover protection to all breakers at Raichur TPS at

the earliest.

Y-ph Pole of Tie-breaker of Unit-4 at RTPS failed.

Unit-4 got tripped on operation of Generator

Differential, Reverse power & LBB protection.

Operation of LBB protection led to tripping of BUS-2

at RTPS

13-04-2016 at

21:12 hrs

Tripping of 400kV Raichur

TPS

Bus-2

Annexure-II

Page 15 of 30


Sedam, Shahapur, Shahabad,

Kapanoor, Humnabad and

Halabarga Stations of

KPTCL

01-02-2018

at 17:46 hrs

High resistance fault occurred in 110kV Sedam-

Chittapur line near Sedam end. Line DEF operated and

backup OC protection of 100MVA transformer

operated at Sedam end. But line breaker and

transformer HV breaker didn’t open due to problem in

trip circuit. This resulted in cascade tripping of

upstream feeders and power supply was lost to six

220kV stations of KPTCL.

KPCL to disable GFC protection on all lines

emanating from their generating stations.

KPCL Review Meeting on 21.12.2018

KPCL informed that compliance w.r.t. Implementing the recommendation would be

furnished soon.


'GFC protection will be disabled in all lines in coordination with M/s.KPTCL

KPCL mail dated 10.05.2019 & 25.06.2019:

Letter addressed to CE, RT, KPTCL dated: 10.04.2019 to disable GFC protection

in all 220kV lines . Reply is awaited.

Pending


Varahi power station

15-03-2018 at

22:36 hrs

There was Y-phase to ground fault on 220 kV Varahi -

Shimoga line-2. Consequent to persisting fault in ‘Y’

phase, the breaker failure protection operated resulting

in operation of 220KV bus bar protection at Varahi,

tripping all the connected lines and Varahi running

units.

KPCL to take steps to put double-bus operation into

service at their 220 kV Varahi PH.

KPCL Status received vide mail dated 25.07.2018:

Under Implementation.

KPCL mail dated 20.12.2018 & 23.01.2019 & 23.03.2019:

Retrofitting of 220kV Bus Isolators is under progress. Proposed to be in service after

April-2019


4 Set of Isolators of VS1, VS2 & VM2 bay of North Bus were cmpleted. Remaining

Pending

78/I/1 Complete Outage of 220 kV

Varahi UGPH.

24-08-2018 at

11:00 hrs

Due to suspected mal-operation of 220KV bus bar

protection at Varahi, all the connected lines and Varahi

running Units got tripped. (6 nos 220kV lines and 4

nos Varahi generating station running Units). This

resulted in complete outage of 220kV Varahi UGPH

1. KPCL to take steps to put double-bus operation into

service at their 220 kV Varahi UGPH by December,

2018.

2. KPCL to employ correct operational practices like

keeping DC fuses of B/C CB intact during bus

changeover works, disabling back-up protections of

B/C CB during bus changeover works & enabling

them with proper settings only when it is used as Main-

CB of the grid elements.

KPCL KPCL mail dated 20.12.2018 & 23.01.2019:

1. Retrofitting of 220kV Bus Isolators is under progress. Proposed to be in service

after April-2019 --- Pending

2. ---- Completed.


1) Retrofitting of 220kV Bus Isolators is under progress. Proposed to be in service

after April-2019



bays will be completed after Concurrence of LC from LDC.



bay will be completed after monsoon season i.e during November -2019

Pending

82/I/3 Complete Outage of 220kV

Kadra Power House of

KPCL & 220kV Karwar SS

of KPTCL

04-02-2019 at

20:19 hrs

During de-synchronising of Kadra unit#2, R-pole

didn’t open due to struck breaker condition. Pole

Discrepancy operated. All the connected 220kV lines

at Kadra end were hand tripped.

1) KPCL to ensure that DR and EL for all events are

made available. If Static relays with no DR are present

in Station, standalone Disturbance recorder and Event

logger should be provided.

2) KPCL to investigate the operation of Negative

KPCL KPCL mail dated 10.03.2019:

1) Preparation of technical specification is completed. Tender will be floated during

3rd week of May- 2019 for control & protection system along with SCADA.

2) English Electric make static type relay is used for NPS protection system at Unit

no.2. The detailed report shall be furnished shortly.

Pending


Kodasalli HEP of KPCL

30-05-2019 at

13:34 hr.

Bus isolator of Unit-3 opened online due to DC earth

fault which in turn led to occurrence of fault. Delayed

clearance of fault (200msec) observed from PMU data.

It was reported that there was operation of LBB

protection of Unit #3 CB. All connected elements got

tripped at 220 kV Kodasalli Hydro station

1.KPCL to explore the possibility of providing double

Bus operation at Kodasalli GS. The existing Transfer

bus may be used as Main Bus also under normal

conditions and as transfer bus under emergency

conditions.

2.KPCL to ensure proper sealing of all the Marshalling

Box at Kodasalli.

KPCL Yet to be informed Pending


1. In view of operating 220kV Ambewadi SS in split bus mode, action is being taken

up by KPTCL. Problem in the 220kV bus coupler breaker is attended and isolator

overhauling work is under progress. Spilt bus operation at Ambewadi will be made

possible at the earliest. --- Pending

2. ICT Protection system at Ambewadi and trippings occured at Supa GS during the

instance is checked up and remedial measures already furnished in this regard.

---- Completed

Mail recieved on 29-07-2015:

GD-1 at 220kV Ambewadi

Station of KPTCL

1. Till the completion of R&M works for bus bar and

LBB protection, KPTCL shall explore the possibility

of having split bus operation at Ambewadi and submit

the details of the same to PCSC forum.

2. KPTCL shall provide the details of the tripping of

Supa hydro station connected downstream from 110

kV bus.

40/I/1 Pending22-12-2014

at 21:22 hrs

KPTCLTriggering incident was B-phase to earth fault in

220kV Ambewadi- Nagzari line-1. B-pole of breaker

did not open at Ambewadi end. LBB protection not

available at Ambewadi end. All elements tripped on

Zone-2 from remote ends.

Annexure-II

Page 16 of 30

KPTCL Mail dated 16.12.2017 & Review Meeting dated 19.12.2017:

1. Recommended works at Ambewadi have not been taken up due to various problems

faced due to poor response from the turn key agency M/s ERL. A site meeting is

planned during this month to discuss about further plan of action for attending SRPC

recommendations pertaining to the Sub station.

The issue was discussed in the review meeting. Considering the importance of the

substation and delay in executing the works, it was decided to escalate all pending

issues relating to Ambewadi SS to KPTCL top Management for early completion.

KPTCL mail dated 20.12.2018:Mail received on 28-04-2015:

Procurement of Bus bar and LBB protection is in the final tendering stage. 2. Action

is being taken to restore the carrier protection for 220kV Sedam-Tandoor line. AR

will be enabled.


1. Procurement of Bus bar and LBB protection is in the final tendering stage. KPTCL Mail dated 16.12.2017:

1 & 2) Replacement of Bus Bar Protection is included under R&U project. Awarded

to M/s GE Ltd. Panels have alredy been supplied by the Agency. The work will be

taken up on top priority.

Review Meeting dated 19.12.2017:Mail received on 27-05-2015:

1. Bus Bar protection will be provded under R&U.

2. A/R yet to be enabled.


1. Procurement of Bus bar and LBB protection is in the final tendering stage.

2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor

line. AR will be enabled after restoration of PLCC.

KPTCL Mail Recieved dated 22-11-2017:

Bus Bar Protection panel and required Wave traps are supplied under R&U. Wave

trap to be commisioned in Tandoor line and PLCC to be restored.Once PLCC is

restored AR will be enabled.


1. Replacement of Bus Bar Protection is included under R&U project. Awarded to

M/s GE Ltd. Panels have alredy been supplied by the Agency. The work will be taken

up on top priority.

2. AR feature will be enabled during retrofitting of Main-2 relays.


1 & 2) KPTCL informed that the works are under progress and are targeted to be

completed by February, 2018. Review meeting on 27.06.2019:

1. Timeline - September 2019

2. Completed


1. Procurement of Bus bar and LBB protection is in the final tendering stage.

2. Action is being taken to restore the carrier protection for 220kV Sedam-Tandoor

line. AR will be enabled after restoration of PLCC.

KPTCL Mail Recieved dated 22-11-2017 & 16.12.2017:

1.Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-

Ponda and Ambewadi-Xeldom lines are radial lines, it was decided that enabling AR


The protection issues pertaining to Ambewadi was appraised to the management

and proposal for construction of new GIS SUb stations has been approved by KPTCL

management. Further as per SRPC directions and in view of attending protection audit

recommendations pertaining to Ambewadi SS without linking with new Station

proposal, action has been taken to include the works in extended scope of R&U

project awarded to M/s GE T&D India Limited. Addition materials required are yet to

be supplied by M/s GE. work expecnted to be completed in 5 months.


1. Since 220kV Ambewadi -Ponda line is radial, this recommendation is dropped.

2. Timeline will be in timated by KPTCL

Pending

Fault in 220kV Ambewadi-Nagjheri line-2

GD-1 at 220kV Ambewadi

Station of KPTCL


Ambewadi substation of

KPTCL

12-03-2015 at

7:51 hrs





2. KPTCL shall provide the details of the tripping of

Supa hydro station connected downstream from 110

kV bus.

40/I/1

41/I/4

Pending

1. Status?27-01-2015 at

8.00 hrs

Pending22-12-2014

at 21:22 hrs

1. KPTCL to provide Bus bar and LBB

protections for 220 kV bus at Sedam S/s.

2. KPTCL to implement A/R feature on 220 kV

Sedam-Tandur inter-state line.

Complete outage at 220kV

Sedam Substation of KPTCL

(GD-1)

42/I/2

(GD)

1. KPTCL to provide Bus Bar protection and LBB

protection at Sedam S/s and furnish the status of their

implementation to PCSC forum.

2. KPTCL to implement A/R feature on 220 kV Sedam-

Tandur inter-state line.

Fault occurred in 220kV Sedam-Shahpur line15-02-2015

at 14:24 hrs

Complete outage of 220kV

Sedam substation of KPTCL

KPTCL

KPTCL1. KPTCL shall provide A/R feature on Ambewadi –

Ponda 220 kV D/C inter-state line.





KPTCLTriggering incident was B-phase to earth fault in

220kV Ambewadi- Nagzari line-1. B-pole of breaker

did not open at Ambewadi end. LBB protection not

available at Ambewadi end. All elements tripped on

Zone-2 from remote ends.

R-Phase to ground fault occurred on 220kV Sedam-

Shahpur line. Fault not cleared from Sedam end due to

stuck-breaker condition. While the Sedam- Sahapur

line tripped from Shahapur end in Zone-1, the other

220 kv lines from Sedam tripped at remote ends in

Zone-2. This caused complete outage of 220kV Sedam

substation.

42/I/1 PendingKPTCL

Annexure-II

Page 17 of 30

KPTCL mail received on 23-01-2016:

Will be complied in a months time.


Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-


is not required. To clear the faults in the abovelines early, the timings of the Zone 2

was reduced to 150mS and the Back Up EFR timings have been reducedto 150mS.


Enabling the AR feature was discussed during PCSC meetings and since Ambewadi-


is not required. To clear the faults in the abovelines early, the timings of the Zone 2

was reduced to 150mS and the Back Up EFR timings have been reduced to 150mS.

In view of the above, it is requested to drop the issue from this list.


KPTCL informed that AR would be enabled at Ambewadi end for lines other than

Ponda and Xeldom lines during retrofitting of Back Up protection by Distance

protection relay at Ambewadi.


The protection issues pertaining to Ambewadi was appraised to the management

and proposal for construction of new GIS SUb stations has been approved by KPTCL

management. Further as per SRPC directions and in view of attending protection audit

recommendations pertaining to Ambewadi SS without linking with new Station

proposal, action has been taken to include the works in extended scope of R&U

project awarded to M/s GE T&D India Limited. Addition materials required are yet to

be supplied by M/s GE. work will be completed in 5 months


1. Work order plced. Timeline requested December 2019.

KPTCL Mail received dated 25-04-2017:

Replacement of existing BBP by new BBP with 4 zone protection is being taken up

under R&U.


GE Ltd has already supplied the necessary Bus Bar protection panels for replacement

of the existing static type BBP by new numerical BBP with 4 zone protection under

R&U project. The work of commissioning the same will be taken up shortly.


Due to operational constraints two/ multi bus operation is not being implemented.


It was noted that Shimoga SS is having required configuration for providing double-

bus operation. However, due to large no. of feeders (15 in no) with variable gneration

at certain remote ends like Varahi, the flows on these lines are bound to vary. As such

it is necessary to zero in on appropriate arrangement of feeders on different buses so

that bus-isolators of the feeders are not overloaded.

The issue was discussed. KPTCL was asked to try out multi-bus operation on trial

basis to arrive at suitable arrangement of feeders.


Bus sectionaliser breakers have to be provided for operating Shimoga in multi bus

mode. Estimates have to be prepared by CEE,TZ,Hassan. Work expected to be

completed in 1 year.


1. The necessary Bus Bar protection panels are already supplied to Chikkodi under

R&U project. Presently R&U works at sub stations subjected to audit are taken up.

After completion of PAR works, the baove works are planned.

--- Pending

2. --- Pending

3. --- Pending


1.The necessary Bus Bar protection panels are already supplied to Chikkodi under

R&U project. Control cables have to be supplied. Presently R&U works at sub

stations subjected to audit are taken up. After completion of PAR works at 26 Sub

stations, remaining works will be taken up through M/s GE.

--- Pending.

2. --- Pending

3. --- Pending


1. KPTCL informed that BBP would be provided by April, 2018.

---- Pending

Tripping of 220 kV Chikkodi-

Mudshingi and 220 kV

Chikkodi-Talandage lines

01-07-2016 at

03:03 hrs

Pending220kV Bus Bar protection operated during failure of R

phase CT in DVG-2 line bay.

22-02-2016 at

15:03 hrs


Shimoga substation

57/II/1 Pending

KPTCLKPTCL to operate 220 kV Shimoga on multi-bus

operation under normal conditions, and put it on single-

bus operation only under emergency conditions.

52/I/3

Pending Status?KPTCL KPTCL to fast-track providing A/R on all 220 kV

lines emanating from Ambewadi SS to prevent Station

shut-down on temporary faults.

Triggering incident was failure of B-ph PT of 220kV

Bus-2 (western bus) at 220KV Chikkodi substation.

220KV Chikodi- Belgaum-I line tripped on DEFR

(Inst), 220KV Chikkodi-Kudachi line tripped on

Distance protection and also 100MVA transformer-2

tripped on E/F protection.

48/I/3

KPTCL1.KPTCL to take steps to provide busbar protection at

their 220 kV Chikkodi inter-regional substation, and

furnish a time-line for the same.

2.KPTCL to review distance protection settings for

220 kV Chikkodi – Kudachi line.

3.KPTCL to furnish equipment failure report of the

current incident to PSE&TD Division of CEA with a

copy marked to SRPC.

220kV Ambewadi-Nagjheri line-2 tripped on B-phase

to earth fault. This resulted in loss of supply to 220kV

Ambewadi bus. 220kV Ambewadi-Ponda line-1&2

were hand tripped after deenergization of bus at

Ambewadi.

30-09-2015 at

10:41 hrs

Outage of 220kV Ambewadi

station in Karnataka

Annexure-II

Page 18 of 30


1). Bus Bar Protection work is included under R&U. work expected to be completed

in 3 months ---- Pending

2). Major equipment failure reports are being sent to CEA regularly ----

Completed.


1. Timeline for completion of work is September 2019

2. Completed

KPTCL mail received dated 25.04.2017:

Numerical BBP is being provided under R&M works.


1). The R&M work of 220kV Hoody SS is under progress and expected to be

comleted before the end of August 2019. Providing Bus Bar Protection to 220kV

buses is a part of R&M work at Hoody ----- Pending

62/II/5 Tripping of 220 kV South

Bus and connected elements

(220kV HSR, 220kV

Nagnathpura, 220 kV

Harohalli, 220 kV

Subramanyapura, 220 kV

20-01-2017 at

14:34 hrs

Triggering incident was fault in 66 kV Somanahalli -

Bannerghatta line and fault was cleared by operation of

Back-up OCR at Somanahalli end.

KPTCL to provide numerical Busbar Protection at

their 220 kV Somanahalli SS at the earliest.

KPTCL KPTCL mail received dated 25.04.2017:

Numerical BBP is being provided under R&M works


Tesing & Commissioning of numerical BBP at Somanahalli is under progress. There

was some technical issue wth BBP scheme supplied to Somanahally which is being

Pending


Ambewadi station

02-04-2018 at

13:46hrs

Loss of supply occurred to 220 kV Ambewadi station

due to tripping of 220kV Nagzhari-Ambewadi line-2

(Source) from Nagzhari power station. After bus dead,

Ambewadi-Ponda lines – 1 & 2 were hand-tripped. In

antecedent conditions, 220kV Ambewadi - Nagjheri

ckt-1, 220kV Ambewadi-Narendra Ckt-1 &2 were out

of service.

1). KPTCL to review operation of SPS at NPH for

proper functionality and changed network conditions

(reduction of generation with tripping of evacuating

lines) and put it into service at the earliest.

2). KPTCL to furnish equipment failure report of the

current incident (R-phase CT in Nagjheri – 1 bay at

KPTCL KPTCL mail dated 20.12.2018:

1). To be reviewed. Expected to be completed in 1 month.---- Pending

2), Being followed ----- Pending


1. Nagjheri SPS shall be studied in view of changed system configuration

Pending

74/II15 Multiple Trippings at

400/220kV Guttur station

21-04-2018 at

12:50 hrs

Triggering incident was fault in 220 kV Davanagare -

Shimoga line. Bus bar protection operated at Guttur

resulting in tripping of all the connected elements. 220

kV Guttur was on single bus operation due to CVT

problem in Bus-2.

KPTCL to put double-bus operation at their 220 kV

Guttur substations by attending to Bus-2 CVT

problem.

KPTCL KPTCL mail dated 20.12.2018:

Bus-2 CVT problem is attended. However due to breaker replacement works, 220kV

side operated in single bus mode.


KPTCL informed that double-bus operation at their 220 kV Guttur would be provided

within two months.

Pending

79/III/9 Tripping of 400 kV JSWEL

–Guttur line

29-09-2018

at 11:30 hrs

R-phase to earth fault occurred in line. Auto-reclose

was not attempted at JSWEL due to DT receive. At

Guttur end auto-reclose could not be validated with

DR/EL.

KPTCL to furnish a detailed report on tripping event

bringing out reasons for DT sending from Guttur end

to JSWEL on 400 kV Guttur - JSWEL line along with


KPTCL Review Meeting on 21.12.2018:

KPTCL was aksed to furnish status of implementation of the recommendation given

at the earliest.


Pending

80/II/7 Tripping of 400 kV JSWEL-

Guttur line

17-10-2018 at

02:04 Hrs

Triggering incident was R-phase to earth fault in line.

At Guttur end there was operation of pole discrepancy

and resulted on tripping of Y & B pole after a duration

of 2 seconds from the occurrence of fault. FIR, DR &

EL of Guttur end were not furnished.

KPTCL to examine the reasons for sending of DT from

Guttur end to JSWEL end, and furnish an action taken

report including remedial measures taken to rectify the

same.

KPTCL Review meeting on 27.06.2019:

report will be submitted by KPTCL

Pending


Ambewadi Station of

KPTCL

06-02-2019 at

14:51hrs

Fault occurred while test charging of 220kV

Ambewadi – Nagjheri Line -2 from Ambewadi end.

Suspected stuck breaker condition at Ambewadi end)

led to clearing of fault by tripping of remote end

breaker in Zone-2. LBB protection is not active at

220kV Ambewadi station.

KPTCL to investigate the reason for non-tripping of

220kV Ambewadi - Nagjheri line-2 on operation of

SOTF and submit a report regarding the same to

SRPC. Also KPTCL to take necessary measures in

order to ensure healthiness of breaker before

testcharging of any line.



Pending

09-01-2017

at 23:06 hrs

1. KPTCL to provide Busbar protection at their 220

kV Hoody SS at the earliest.

2. KPTCL to furnish an Equipment Failure Report on

CT failure to CEA with a copy marked to SRPC.

Failure of R-phase CT of 220/ 66 kV transformer-2 at

220kV Hoody end resulted in a bus fault in 220kV Bus-

2. Fault was cleared by backup protection of ICT's

(220kV lines were being radially operated) due to

absence of busbar protection

Tripping of 220 kV Chikkodi-

Mudshingi and 220 kV

Chikkodi-Talandage lines

01-07-2016 at

03:03 hrs

57/II/1 Pending

Pending

Triggering incident was failure of B-ph PT of 220kV

Bus-2 (western bus) at 220KV Chikkodi substation.

220KV Chikodi- Belgaum-I line tripped on DEFR

(Inst), 220KV Chikkodi-Kudachi line tripped on

Distance protection and also 100MVA transformer-2

tripped on E/F protection.

Tripping of 220 kV Bus 2

and connected elements

(220kV HAL #1 and 2,

400/220 kV ICT- 1, 2 and

220/66 kV ICT-2) at

400/220 kV Hoody

substation of KPTCL (Load

loss : 590 MW)

62/II/3

KPTCL1.KPTCL to take steps to provide busbar protection at

their 220 kV Chikkodi inter-regional substation, and

furnish a time-line for the same.

2.KPTCL to review distance protection settings for

220 kV Chikkodi – Kudachi line.

3.KPTCL to furnish equipment failure report of the

current incident to PSE&TD Division of CEA with a

copy marked to SRPC.

KPTCL

Annexure-II

Page 19 of 30


Alipura substation

20-02-2019 at

12:45 hrs

As informed by KPTCL, Suspected delayed clearance

of fault in 220 kV BTPS-Lingapur line from BTPS end

resulted in tripping of lines from Alipura S/s.

1) KPTCL is recommended to furnish detailed report

regarding spurious operation of DEF at Alipur SSand

check the directionality of DEF on all lines.

2) KPTCL is requested to share the revised zone

settings for Distance protection at BTPS end.



Pending

82/II/12 Tripping of 400kV Kaiga-

Guttur line-1&2

07-02-2019

at 11:49 hrs

Line-1 tripped due to insulator flashover. Line-2

tripped due to zone-3 operation at Kaiga and Direct

trip receive at Guttur

KPTCL is recommended to take necessary measures to

ensure that Main-I and Main-II at Guttur end shall be

of different types (make and model) coherent with the

general protection philosophy followed in SR region.


KPTCL informed that the recommendation has been included as part of R & M work.

Timeline will be informed

Pending

84/II/12 Tripping of 400kV DHONI

GUTTUR line- 1

18-04-2019 at

18:59 hr.

Triggering incident was failure of B-ph CB of 400kV

Dhoni-Guttur line at Dhoni end. This resulted in the

operation of LBB of bus-1 and DT was sent to Guttur

end

1. KPTCL to send equipment failure report,

corresponding to the failed CB at Dhoni SS, to CEA.

2. KPTCL to ensure time synchronization at Guttur

end.

KPTCL Yet to be informed Pending


Nelamangala-Mysore line-2

01-05-2019 at 02:29 hr.Line tripped on operation of over voltage stg-2 at

Nelamangala end

KPTCL to ensure time synchronization of DR and

EL with GPS signal at Nelamangala end.


Annexure-II

Page 20 of 30


1&3 at Hoody Substation

13-05-2019 at

15:35 hr.

ICT-3 tripped on operation of 59N neutral

displacement relay. ICT-1 tripped on OCR.

KPTCL to inform PCSC forum regarding the changes

implemented in Hoody ICT SPS and to ensure time

synchronization of relays at Hoody SS.



1. coordination of KPCL has been requested for enabling AR lines terminated to

Nagajari.

2. AR will be enabled at Ambewadi end for lines other than Ponda and Xeldom lines

during retrofitting of Back Up protection by Distance protection relay at Ambewadi.

KPTCL Mail dadted 16.12.2017 & Review Meeting dated 19.12.2017:

1. KPTCL informed that Coordination of KPCL has been requested for enabling AR

lines terminated to Nagajari.

--- Pending

2. KPTCL informed that AR would be enabled at Ambewadi end for lines other than

Ponda and Xeldom lines during retrofitting of Back Up protection by Distance

protection relay at Ambewadi. -- Pending


2). Readiness from KPTCL for implementing AR is already confirmed to KPCL. KPCL mail dated 23.03.2019:


version Numerical Line protection relays having IEC61850. Prepration of

specification is under progress.


1) Budgetary offer obtained for replacement of existing PZ1000 relays with new

version Numerical Line protection relays having IEC61850. Preparation of estimation

and specification is under progress.


1) Replacement of existing PZ1000 relays with new version Numerical Line

protection relays having IEC61850 is included in PSDF Phase-II DPR. Approval of

NLDC for DPR is awaited. Further, availing administrative approval for issue of NIT

for replacement of existing PZ1000 relays with new version Numerical Line

protection relays having IEC61850 and preparation of estimation and specification is

under progress.

Status informed during Special Meeting held on 03.06.2016:

1. KPTCL informed that the matter had been taken up with concerned Line Operation

and Maintenance wing to carry out corridor clearance and maintenance as per

schedule to avoid frequent line faults in this corridor. A letter had also been addressed

to Chief Engineer, Bhagalkot zone, to ensure lines in & around Kali complex are

maintained in healthy condition. --- Completed

2. KPTCL assurd that the final modified SPS would be implemented at Nagjheri PH


1) & 3). --- Completed.

2). Proposed revision in existing SPS scheme is already submitted to SRLDC/SRPC.,

yet to be discussed and approved by the SRPC forum --- Pending


2. The SPS proposed by KPTCL was discussed and the PCSC forum suggested

certain changes for suitable incorporation. KPTCL agreed to look into the same and

assured that the modified SPS would be furnished by January, 2018.


2. KPTCL informed that Nagjheri SPS shall be finalised in 1 month.

KPCL mail dated 23.01.2019 & 23.03.2019:

1) .....Completed


3) .....Completed

KPCL mail dated 13.05.2019 & 25.06.2019

1. 3. Completed



51/I/3 KPCL/ KPTCLComplete outage of 220 kV

Nagjheri power station and

220 kV Ambewadi

substation of KPTCL

Pending22-02-2016 at

12:36 hrs

1. To avoid tripping of transmission lines on transient

faults, KPCL/ KPTCL is recommended to carry out

periodic patrolling of lines, and ensure their proper

maintenance by carrying out jungle/ bushing clearance

and trimming of tree branches within the RoW of

transmission lines as per the SRPC transmission line

patrolling guidelines (available under the menu item

"All Uploads/ Operation/ Miscellaneous/ Transmission

Line Patrolling Protocol / Guidelines for Southern

Region" on SRPC website).

2. KPCL/ KPTCL to review operation of SPS at NPH

for functionality (reduction of generation with tripping

of evacuating lines) and healthiness.

3. KPCL to put 220 kV Kodasalli - Nagjheri D/C lines

into service if more than 200 MW generation from

Kali Complex (with Nagheri Contribution not less than

50 MW) is ensured on sustained basis.

Pending

220kV lines from Nagjheri power house started

tripping from 11:00 hrs due to fault in lines. The

sequence of tripping is shown in SOE list. At 12:33

hrs, 220kV Narendra-Ambewadi lines-1&2 got tripped

which resulted in loss of evacuation path to Nagjheri

station resulting in tripping of running Units and

complete outage at Nagjhheri power station. 220kV

Ambewadi station also got de-energized due to tripping

of source feeders i.e. 220kV Narendra-Ambewadi-1&2

and 220kV Nagjheri-Ambewadi-1&2.


Ambewadi Substation of

KPTCL

29.10.2015 at

14:34 hrs

1. KPCL to provide A/R on all 220 kV lines emanating

from Nagjheri PH.

2. KPTCL to provide A/R on all 220 kV lines

emanating from Ambewadi SS.

KPCL/ KPTCL220kV Nagjheri-Ambewadi line-1 tripped at 13:33 hrs

due to B phase to earth fault. Ambewadi was radially

fed from Nagjheri power station through 220kV

Nagjheri-Ambewadi line-2. Tripping of this line

caused 220kV Bus shut down at Ambewadi and

remaining lines and transformers were hand tripped

Annexure-II

Page 21 of 30

KPCL mail dated 23.01.2019 & 23.03.2019:

1) …Completed.


3) …Completed.

KPCL mail dated 10.05.2019 & 25.06.2019:

1. & 3. Completed




2. KPTCL informed that Naghjeri SPS need to be revisited in view of changes in

system configuration.

KPTCL Mail received dated 28-06-2016:

Modifications to be carried in Nagzari SPS logic is submitted to SRLDC/SRPC for

verification and approval


1. Tripped since there was evacuation problem and there were only two lines NA-1

and NA-2 ---- Completed

2. Will be reviewed in consultation with EE(RT), KPTCL, Hubli. --- Pending

3. Both the lines are in charged condition. --- Completed.


2. Proposed revision in existing SPS scheme is already submitted to SRLDC/SRPC.,

yet to be discussed and approved by the SRPC forum. --- Pending


1) & 3). --- Completed.

2). Proposed revision in existing SPS scheme is already submitted to SRLDC/SRPC.,

yet to be discussed and approved by the SRPC forum --- Pending


2. The SPS proposed by KPTCL was discussed and the PCSC forum suggested

certain changes for suitable incorporation. KPTCL agreed to look into the same and

assured that the modified SPS would be furnished by January, 2018.


KPTCL informed that Nagjheri SPS shall be finalised in 1 month.

53/I/3 PendingKPCL/ KPTCLAmbewadi Narendra line-2 tripped on fault and 220kV

ambewadi Narendra line-1 tripped due to over-loading.

Running Units at Nagjheri also tripped during the event

due to tripping of evacuating lines

1. KPCL to furnish a report on the reasons for Unit-6

tripping at Nagjheri PH.

2. KPCL/ KPTCL to modify suitably the SPS at

Nagjheri Power House such that it would also factor in

the over loading of Ambewadi-Narendra lines.

3. KPCL to put 220 kV Kodasalli - Nagjheri D/C lines

into service if more than 200 MW generation from

Kali Complex (with Nagheri Contribution not less than

50 MW) is ensured on sustained basis.

Tamil Nadu


Ambewadi station of

KPTCL and 220kV Nagjheri

of KPCL

18-03-2016 at

14:40 hrs

Annexure-II

Page 22 of 30

TANTRANSCO Mail received on 19-02-2016 and 24-03-2016:

Revision of Bus Bar Protection setting was carried out. The stabilizing voltage

setting was raised from 410 to 450 volts. After completing the necessary test, the bus

bar protection put in to service on 29.12.2015.

Mail Received on 27-04-2016 ,16-06-2016,25-07-2016 & 24-09-2016:

Revision of Bus Bar Protection setting was carried out. After completing the

necessary test, the bus bar protection put in to service on 29.12.2015.

Mail received on 10-11-2016 & 20.12.2016:

Provision of Bus Coupler bay arrangement was included in the Upgradation works

proposed and the same was sanctioned by MoP through PSDF.

Numerical relay allotted and being commissioned.


Numerical BBP relay was commissioned on 02.02.2017

Status received vide mail dated 12.04.2017 & 01.06.2017 & 15-06-2017:

Numerical BBP relay was commissioned on 02.02.2017.

Provision of Bus Coupler bay arrangement was included in the Upgradation works

proposed and the same was sanctioned by MoP through PSDF.


Numerical BBP relay was commissioned on 02.02.2017.Status received vide mail dated 18-09-2017 & 31-20-2017:

Numerical BBP relay was commissioned on 02.02.2017. Provision of CT in Bus

Coupler bay is arranged and zone segregation will be provided.

Status received vid email dated 12-12-2017:

Numerical BBP relay was commissioned on 02.02.2017. Provision of CT in Bus

Coupler bay has been allotted. Zone segregation will be provided after commissioning

of CT.


TANTRANSCO informed that the recommendation would be complied with by

March, 2018.

TANTRANSCO Mail received on 25-01-2018:Status received vid email dated 11-12-2018:

Civil work completed & CT will be commissioned after strengthening Bus .2

conductor jumpers.Awaiting Bus LC Time line before January 2019.


Erection under progress will be completed before 31.01.2019


Buscoupler bay will be commissioned by June 2019


Buscoupler bay configuation in BBP will be completed by June 2019. Bus

segregation will be ensured by 31.12.2019 after attending Isolator status feedback.

62/II/7 25-01-2017 at

22:36 hrs

PendingTANGEDCO mail dated 15.04.2017:

1) New Relay is tested and ready for replacement.Now all 5 units are in service.The

relay will be replaced when lesser units are in service. --- Pending

2.a)Steps are taken to renovate & mordernization of all the control panel into

Numerical based control panels. --- Pending

2.b) Since 230 KV indoor switchyard has no spare space providing dual CT`s is not

fessible. -- Completed

3) Procurement of EL & DR is under progress. --- Pending

TANGEDCO mail dated 26.04.2017:

1) Check zone New Relay is replaced on 17.04.2017 -- Completed.

2. --- Pending

3. --- Pending

TANGEDCO mail dated 13.12.2017:

2).P & C wing gives clearance to TTPS to procure the Bus bar protection relays and

protection relays and SER / DR system vide

Lr.CE/P&C/SE/D/EEPC4/AEE3/F.TECH/D.27/17 Dated: 05.10.2017. To get

administrative approval budgetary offer has bar protection relay from various

companies ----Pending

3). SRPC vide Lr: SRPC/SE- III/CEA/2017/6450/DT:27.10.2017 gives features of

SER/DR. Budgetary offer will be called for SER / DR having above features. ---

Penidng


TANGEDCO

21-12-2015 at

6:28 hrs


Mywadi station of

TANTRANSCO

Failure of Bus Section-I Y-ph CT resulted in operation

of bus-bar protection for Bus Sections -I & II. Running

Units#1, 4 and 5, 230 kV Kayathar, 230kV

Kudankulam, 230kV Sterlite, Station Transformer-1, 2

& 3 got tripped during the incident. Unit – 2 & 3 were

not in service.

Tripping of running Units &

230kV feeders at Tuticorin

TPS of TANGEDCO

(Gen Loss: 640 MW)

Busbar protection got operated for a fault in 230kV

Mywadi-Anaikadavu line

TANTRANSCO to examine the feasibility of

providing two main-zone operation for bus bar

protection by exploring various alternatives like

replacing existing bus-coupler CB with a hybrid bus-

coupler CB that comes with inbuilt CT, replacing

existing BBP relay with another suitable relay that

supports two main-zone operation, and implement the

same.

Pending

Status?1. TANGEDCO to replace existing Check-Zone relay

with a new one possessing required performance.

2. TANGEDCO to take steps to provide numerical

busbar protection at their 220 kV Tuticorin TPS.

TANGEDCO may also explore providing dual CT’s

(on either side) for all B/S breaakers at the time of

commissioning of numerical BBP, if there were no

space constraints.

3. TANGEDCO to take steps to provide for standalone

Event Logger (EL) and standalone Disturbance

Recorder (DR) with automatic downloading facility to

a centralized server.

TANTRANSCO

Annexure-II

Page 23 of 30

TANTRANSCO mail received on 25-01-2018:

1) Commissioning of Bus Coupler CT, Extended Bus with Additional Bus Coupler is

under progress. Timeline: June-2018.

2) Numerical BBP commissioned on 29.08.2017 to enable Bus seggregation.

3) Providing Re-Trip feature for LBB will be studied.


Providing new Bus coupler bay involes bay shifting work.work awarded and under Status received vid email dated 11-12-2018:

Bus coupler erected and commissioning schedule on 18.12.2018.


1. Bus coupler errected and commissioning would be completed by January 2019 ---

Pending

2. -----Completed

3. Works would be completed by Janaury, 2019 --- Pending.Mail recieved on 25-07-2016 & 24-09-2016:

TANTRANSCO: Auto Transformer-2 HV side Bus isolator 'C'-phase support

insulator of 230kV Southern Bus was replaced and Bus Bar Protection scheme was

restored on 12.05.2016.

Status received vide mails received on 10-11-2016 & 20.12.2016 & 12.04.2017


Numerical Busbar protection relay commissioned on 14.05.2018


Control & Status of isolator feedeback to be provided by replacement of Drive


New 230kV isolators have been allotted for replacement of defective isolators. Hence

time line requested upto June.2019.

The issue was discussed in PCSC-58 meeting held on 18.10.2016, when PCSC forum

agreed to de-link the implementation of the Item from the scope of Protection Audit

Recommendations (PAR), and pursue it as part of PCSC Recommendations.

Status received vide mails dated 10.01.2017 & 12.04.2017 & 01.06.2017 &15-06-

2017 & 04.08.2017 & 18.09.2017 & 31-10-2017& 12-12-2017:

Different make Relays will be provided for Main-I & II relays at Sunguvarchatram

end in a phased manner.


TANTRANSCO informed that the recommended works of providing different make

Relays for Main-I & Main-II are targeted to be completed by September, 2018.


provision of Different make Relays for Main-I & Main-II will be completed by

September, 2018.



end in a phased manner. Timeline: September-2018.




TANTRANSCO MAIL DATED 11-12-2018:


Pending

1. TANTRANSCO to provide split-bus operation with

bus sectionalizer CB for their 230 kV Madurai

(Chekanurani) SS.

2. TANTRANSCO to provide two main-zone

operation for the numerical BBP that is being

commissioned.

3. TANTRANSCO to examine the feasibility of

providing Re-Trip feature for the LBB protection, and

accordingly take steps for implementing the same.

TANTRANSCO

55/I/1

(GD)


Gummidipoondi Station of

TANTRANSCO

12-05-2016 at

12:15 hrs

Flashover of Auto Transformer- 2 HV

B-phase Isolator supporting insulator of 230kV

Southern Bus occurred at Gummidipoondi station. At

the time of fault, Bus bar protection relay was not in

service for pre-commissioning testing of Auto

Transformer-2. All feeders got tripped due to operation

of zone-2 protection from remote ends.

Pending51/I/1

(GD)


Madurai S/s (Chekanaurani)

of TANTRANSCO

19-01-2016

at 11:56 hrs

Fault had occurred in 230kV Madurai-Sembatty line.

Trip from distance relay was not extended to breaker

due to protection DC fail. LBB protection got operated

resulting in a busbar trip at 230kV Madurai substation.

All elements got tripped as there is a single bus

operation at 230kV Madurai S/s

TANTRANSCO


CMR relay for extending LBB protection was released and LBB extended from

Distance Protection relay directly. CT is not available in the Bus Coupler bay for

zone segregation. However, during commissioning of third ICT, Bus section Breaker

will be provided for zone segregation. Numerical BBP relay will be provided.

Status received vide mails recieved on 27-04-2016 and 20-05-2016 ,16-06-2016,

25-07-2016, 24-09-2016,10-11-2016 & 20.12.2016 & 12.04.2017 & 01.06.2017 &

15-06-2017:

1 & 2) CT is not available in the Bus Coupler bay for zone segregation. However,

during commissioning of third ICT, Bus section Breaker will be provided for zone

segregation. Numerical BBP relay will be provided.


1 & 2) Contract awarded for providing third ICT & Bus modification works to

accomodate bus coupler bay. Numerical BBP relay has been provided and tesing

under progress.



accomodate bus coupler bay. Numerical BBP relay has been provided and tesing

under progress.



accomodate bus coupler bay.

Numerical BBP relay was commissioned onj 29.08.2017.

Different type and Make of distance protection relays to be provided for Main-I & Main-II protection for 230kV feeders at 400 kV Sunguvarchathiram & 230 kV

Sunguvarchathiram Substation [Carry-Over from Protection Audit Recommendations]

TANTRANSCO Pending58

TANTRANSCO to take steps to provide double-bus

operation at their 230 kV Gummidipoondi SS.

Annexure-II

Page 24 of 30






end in a phased manner. Timeline: September-201914-09-2016 at

11:13Hrs

Bus Bar Protection (Zone-2) of 230 kV Bus-B got

operated at Alamathy Station during fault in 230 kV

Alamathy-Korattur feeder.

TANTRANSCO MAIL DATED 11-12-2018:

Numerical BBP relay to procured. Timeline: Sep-2019.


Numerical BBP relay to be procured. Timeline: Sep-2019.


Numerical BBP relay to be procured. Timeline: Sep-2019.

Review meeting on 27.06.2019:64/1/4 Complete outage of North

Chennai TPS STG-1

26-03-2017

at 23:14hrs


of running Unit at NCTPS Stg-1

1. TANTRANSCO to take steps to complete insulator

replacement works on the 230 kV lines owned by them

in NCTPS area within 6 months.

TANTRANSCO Status received vide mails dated 04.08.2017 & 18.09.2017 & 31-10-2017:

1. All the Porcelain insulators were replaced with Polymer insulators in 230kV

NCTPS-I - Tondiarpet feeders - 1 & 2.

---- Completed

Pending


2. The scheme needs modification to enable AR, since AR was not envisaged for this

station during commissioning. AR will be implemented on all 230kV lines emanating TANTRANSCO MAIL DATED 11-12-2018:

2. Enabling AR pending for 3 feeders. ( Sriperumpudhur end breaker problem,

Tondiarpet & Alamathy feeder . static relay to be replaced. Timeline - 1 year


Enabling AR pending for 3 feeders. ( Sriperumpudhur end breaker problem,

Tondiarpet & Alamathy feeder . static relay to be replaced. Timeline -Sep 2019

TANTRANSCO MAIL DATED 19.03.2019 & 13.06.2019:77/II/9 Multiple trippings at

400 kV Manali Substation

TANTRANSCO to refer the issue of selective tripping

of 400 kV side breakers, and non-tripping of 230 kV

side breakers due to operation of Densimeters on low

pressure in the instant case to their OEM, and share

OEM’s advice/ remedy in this regard.

TANTRANSCO mail dated 11.09.2018:

OEM will be referred


TANTRANSCO was asked to update the status.

TANTRANSCO MAIL DATED 23.01.2019, 19.03.2019 & 13.06.2019:

The issue was referred with OEM & reply awaited.

Pending


Thiruvalam Substation

05-10-2018 at

14:32 hrs

Bus-1 got tripped at 230 kV Thiruvalam substation due

to spurious LBB relay (independent) operation of

230kV Thiruvalam Chittoor line. 230kV Thiruvalam

substation was under single bus operation; hence

operation of LBB protection resulted in tripping of all

TANTRANSCO to take steps to implement multi-bus,

multi-zone operation (Double-bus operation) at their

230 kV Thiruvalam SS by December, 2018.

TANTRANSCO TANTRANSCO MAIL DATED 11-12-2018:

Due to space constraint, the equipments could not be erected.


It was noted that the station was on a single (Main) bus and there was not even

Pending

15-09-2016 at

22:14 hrs

1. TANTRANSCO to check the healthiness of BBP

relay by conducting stability test, and take appropriate

remedial action like increasing voltage settings,

ensuring the healthiness of CT’s, using CT’s with

similar characteristics (equal saturation effects &

equal winding resistances) etc. at their 230 kV

Alamathy SS.

2. TANTRANSCO to replace the existing high-

impedance BBP relay with its low-impedance/

numerical variant so as to accommodate variation in

CT characteristics at their 230 kV Alamathy SS.

58/II/17 Multiple tripping at 230 kV

Alamathy Station

Mail received on 10-11-2016 & 20.12.2016:

1. The Bus Bar Protection scheme will be tested for healthiness including the CT

circuits.

2. High impedance BBP relay will be replaced by Numerical relay.

Status received vide mails dated 10.01.2017 & 12.04.2017 & 01.06.2017 & 15-06-

2017:

1. The Bus Bar Protection scheme was tested for healthiness including the CT

circuits. AREVA make CTs in Alamathy SS are having different kneepoint voltage

for the cores. CT cores of higher knee point voltage has been choosen for BBP in

230kV Korattur, 230kV OPG-1 & 230kV OPG-2 feeders on 29.11.2016. ----

Completed.

2. High impedance BBP relay will be replaced by Numerical relay. --- Pending,

Status received vide mails dated 04.08.2017 & 18.09.2017 & 31-10-2017 & 12-

12-2017.

1. ---- Completed

2. High impedance BBP relay will be replaced by Numerical relay. --- Pending


2) TANTRANSCO informed that Numerical BBP would be provided by April, 2018

--- Pending


1. --- Complied.

2. High impedance BBP relay will be replaced by Numerical relay. Timeline: April-

2018.

TANTRANSCO MAIL DATED 22.05.2018 & 08.06.2018 & 23.07.2018:

2.Numerical BBP relay will be provided. Timeline: Sep-2018.


1. Complied

2.Numerical BBP relay will be provided. Timeline: Sep-2018.

Pending

Bus Bar Protection (Zone1) of 230kV Bus-A got

operated at Alamathy Station during fault in 230 kV

Alamathy-OPG-1 feeder.

TANTRANSCO

Different type and Make of distance protection relays to be provided for Main-I & Main-II protection for 230kV feeders at 400 kV Sunguvarchathiram & 230 kV

Sunguvarchathiram Substation [Carry-Over from Protection Audit Recommendations]

TANTRANSCO Pending58

Annexure-II

Page 25 of 30

80/II/12 Tripping of all elements

connected to 230 kV

Anaikadavu SS

06-11-2018 at

21:35 Hrs

Triggering incident was failure of R-ph PT of 230 kV

Anaikadavu Bus-1. 230 kV Bus bar protection of bus-

1 operated resulting in tripping of all the connected

elements. 230 kV Anaikadavu was on single bus

operation due to failure of Bus-2 PT during antecedent

1) TANTRANSCO to adopt recommended OVR,

Stage-I and OVR, Stage-II protections at their 400 kV

Anaikadavu and 400 kV Rasipalayam stations, and to

ensure that OVR-I_START signal is configured for

triggering corresponding Event Logger (EL), and OVR-

TANTRANSCO TANTRANSCO MAIL DATED 23.01.2019 & 19.03.2019:

1……Complied

2.Bus PT is to be supplied by the Turnkey contractor will be replaced by 31.03.2019


Pending


Sriperumbudur station

28-01-2019

at 01:15 Hrs

Failure of ‘R-phase’ HV side Current transformer (CT)

of 315MVA 400/230kV ICT-3 at 400kV

Sriperumbudur substation (400kV TANTRANSCO

switchyard).

1) TANTRANSCO to ensure proper legends for DR

Digital signals and all required events(including CB

status, Type of protection operated) are captured in

Event logger.

2) TANTRANSCO to extend BBP trip from BusBar

relay to 86A (with source-1 DC) in addition to 86B

(with source-2 DC), or to provide Common trip relay

96 with redundant DC supply.


1. At present Duobias relay avaiable I/O configuration could not be carried out.after

changing the relay Digital signals will be configured

2.COMPLIED

3.Provision of Numerical BBP relay covered under R&M work. Tender under

progress.

4.out of 30 CTs, 21 No CTs have been replaced with new one.

Pending

83/I/7 Complete outage of

230kV/110kV KR Thoppur

Substation of

TANTRANSCO

11-04-2019

at 13:16Hrs

Triggering incident was failure of Y-ph CT of Bus

Coupler at 230kV KR Thoppur(Salem) SS. Bus bar

protection of Bus-1 and Bus-2 operated resulting in the

tripping of all the connected elements at 230kV KR

Thoppur SS. 400kV/230kV ICT#1 and 2 at Salem also

got tripped during this event.

1.TANTRANSCO informed that replacement of

mechanical relay by Numerical relay is under progress

and it is recommended to submit the action plan

regarding the same with proper time-lines.

2.TANTRANSCO is also recommended to send

equipment failure report to CEA regarding failure of

Bus coupler CT.


1. Replacement of numerical relay under progress

2.Equipment failure report will be sent

Pending

83/II/13 230kV Bus dead at 230/110

kV Pugalur

14-03-2019 at

13:24 hrs

Triggering incident was R-phase breaker failure in

230kV Pugalur end of Budansandhai feeder. LBB

operated resulting in tripping of all connected elements.

As reported, 230kV side was on single bus operation

since bus sectionalizer provision is not there. 110kV

side connected feeders did not trip.

TANTRANSCO is recommended to furnish

equipment failure report to CEA regarding failure of

CB.


Equipment failure report will be sent

Pending


4 AT SRIPERUMBUDUR

15-03-2019 at

13:25hrs

110KV SriperumpudurI.G.Kottai line tripped on Zone-

1, distance protection due to B-N fault. At the same

time, ICT#4 got tripped due to Bucholz relay

operation.

TANTRANSCO is recommended to submit the

tripping files related to ICT-4, and to ensure

healthiness of Buccholz relay by carrying out regular

maintenance activities.


Healthiness of Buch relay checked & found healthy.

Pending

KSEB Mail received vide dated 17.01.2017:

1. 110 kV bus bar protection progressing ----Pending

2. Connection of 220kV earth mat and 110 kV plate earthing system completed.----

Completed

3. Redundancy of 110V DC system in progress. Complete independent redundancy is

not practical for the time being. 48 V DC redundancy was already there. ----

Pending

4. Instead of stand alone event logger, SCADA system of 110 kV feeder is expected

to be completed by the end of 2017. SCADA system of 220kV side will be taken up

Status received vide mail dated 12-12-2017:

1. Detailed engineering of the scheme has been completed. Material procurement is in

progress. ---Pending

2.,3. ---- Completed

4. The SOE and DR are available with time stamping from the numerical relays.

Hence stand alone event logger is not necessary ----- Completed

Status received vide mail dated 11-12-2018:

Work has been already tendered. It is expected that purchase process will completed

Kerala

PED

Triggering incident was conductor snapping in 110 kV

Kalamassery- Kaloor feeder

1. Time-frame?58/I/1

(GD)

KSEB to take steps to provide the following at their

220/ 110 kV Kalamassery SS:

1. Busbar protection at 110 kV level

2. Connecting 220 kV and 110 kV sides on to a

common earthmat

3. Redundant DC supply for both protection (220 V)

and communication (48 V) applications

4. Stand-alone Event Logger

KSEB PendingComplete outage of 220 kV

Kalamassery Substation

23-08-2016

at 11:20 hrs

Annexure-II

Page 26 of 30


Sanction to issue purchase order in progress. Time Frame is January 2020 .

Review meeting on 27.06.2019.

1. BBP will be commissioned by December 2019.

2.,3.,4. Completed

79/I/1 Complete Outage of 220 kV

Idukki Power Station

01-10-2018 at

04:16 hrs

Triggering incident was R-Ph fault in 220kV Idukki-

Kalamassery line-2. R-phase pole of breaker didn’t

open at Idukki end. LBB of Bus-2 operated resulting in

tripping of all connected elements along with running

Unit#4 at Idukki and 50MVA station transformer. At

the same time, 220kV Idukki Kalamassery line-1 also

got tripped at Idukki end. Subsequently running Units 1

and 2 also tripped on Governor oil Low Pressure due to

loss of AC supply. This resulted in complete outage of

1). KSEBL to check & correct the LBB time setting

employed at their Idukki PH to 200 msec.

2). KSEBL o ensure that DR’s & EL’s of all

Protection Relays (PR’s) at their Idukki PH are

configured for recording all mandated protections &

signals.

KSEBL Status received vide mail dated 11-12-2018:

1) Present setting is 180ms.OEM(ABB) suggests that it will give around 200ms

delay as it is having inherent delay is of around 20ms(ie, 180ms +20ms

=200ms).With this setting the fault clearence is found after 220ms.So further revision

may be carried out after discussion.

2)Breaker status will be ready only after completing the GOOSE network as part of

renovation of all feeder panels and Idukki first stage units by June 2019 .

Pending

80/II/5 Multiple trippings at 220 kV

Madakathra station

15-10-2018 at

08:57 Hrs

Triggering incident was Y-phase to ground fault in

220kV Madakathra – Palakkad_KL (Ellapully) line

due to flashover of pilot insulator string. Auto-reclose

was successful at Madakathra end. At the same time

bus differential relay Zone-C mal-operated resulting in

tripping of all elements connected to the bus.

KSEBL to take steps to replace the existing static

(high impedance type) 220 kV BBP with numerical

Busbar protection at their 220 kV Madakathara SS.

KSEBL Status received vide mail dated 11-12-2018:

In progress


Status as on 18.03.2019: Estimate sanctioned by CE(Transmission North ) and have

prepared the technical specifications.Tendering procedures are yet to get started.


Pending


Bhramapuram substation of

KSEB

08-02-2019 at

10:28 hrs

Complete outage of 220kV Brahmapuram SS occurred

due to suspected mal operation of Bus Bar protection.

1) KSEBL to furnish detailed report regarding the

healthiness of BBP operation at 220kV Brahmapuram

after testing of the same on 12th April 2019.

2) KSEBL to submit the action plan regarding

(i) Replacing of the Static High impedance BBP

(using CRM relays) with Numerical BBP.

(ii) Replacement of CRM relays and relays with no

Disturbance recording facilitites.

KSEBL Status received vide mail dated 03.05.2019:

1) Detailed report sent on 02.05.2019…..Completed.

2) As reported earlier in this regard, the permanent solution to this problem is to

replace the existing high impedance static relay with a low impedance numerical

relay. The station authorities have already initiated action to implement the same by

June 2020.

Pending


Edamon SS of KSEB

27-05-2019 at

12:30 hr.

Triggering incident was three phase to earth fault in

220 kV Edamon Bus 1 and 2. Bus 1 and 2 Bus bar

protection operated resulting in the tripping of all

connected elements.

1.KSEBL may develop proper operational code for

procedures to be followed while performing operations

in switchyard and sensitize their operators to reduce

operational errors. 2.ksEBL to ensure time

synchronization of relays at 220 kV Edamon SS.

KSEBL Yet to be informed Pending


1 at Khammam

27-01-2019

at 14:33hrs

ICT-1 at Khammam tripped on operation of IV side

non directional Over-current high set during failure of

L.A in 220kV Khammam (Budhidampadu)-Suryapet

line-2

PGCIL (SR-I) to immediately take necessary actions

to raise the Highset pick up current setting as per

protection standards since unwarranted tripping of ICT

for fault on 220kV line compromises the reliability of

Power system. In any case the transformer protection

should not encroach into protection zone of nearby

protection element.

PGCIL (SR-I) Review meeting on 27.06.2019:

PGCIL (SR-I) informed that the ICT high set settings have been sent by mail

Pending

84/II/3 Tripping of 400kV KTPS-

Khammam line

11-04-2019 at 13:59 hr.Line tripped on operation of overvoltage stage-1

protection at KTPS end and DT received at Khammam

end. Phase voltages at KTPS end could not be verified

from the DR furnished.

PGCIL (SR-I) to ensure time synchronization of DR

and EL at Khammam end.

PGCIl (SR-I) Yet to be informed Pending


2 at Bangalore (Somanahalli)

26-10-2018 at

12:10 Hrs

400/220 kV ICT-2 at Bengaluru (Sonamahalli) tripped

due to operation of LV side over flux protection which

in turn was due to suspected 220 kV CVT problem.

PGCIL (SR-II) to configure DR’s & EL’s all

protection relays at their 400/ 220 kV Somanahally SS

for all mandated protections and signals.

PGCIL (SR-II) Review meetinmg on 27.06.2019:

PGCIL (SR-II) was asked to furnish the status of implementation of the

recommendation at the earliest.

Pending

PGCIL (SR-I) & PGCIL (SR-II)

Triggering incident was conductor snapping in 110 kV

Kalamassery- Kaloor feeder

1. Time-frame?58/I/1

(GD)

KSEB to take steps to provide the following at their

220/ 110 kV Kalamassery SS:

1. Busbar protection at 110 kV level

2. Connecting 220 kV and 110 kV sides on to a

common earthmat

3. Redundant DC supply for both protection (220 V)

and communication (48 V) applications

4. Stand-alone Event Logger

KSEB PendingComplete outage of 220 kV

Kalamassery Substation

23-08-2016

at 11:20 hrs

Annexure-II

Page 27 of 30


Somanahalli-Dharmapuri

line-2

07-04-2019 at

18:02 hr.

Line tripped on operation of over voltage stage-1

protection at Somanahalli. Somanahalli end DR: Vr-

240kV, Vy-253kV, Vb-241kV. Y-phase voltage was

higher than R and B phase

1. PGCIL (SR-II) to configure OVR start and OVR

trip signal in Event logger to facilitate verification of

adopted OVR grading.

2.PGCIL (SR-II) to ensure time synchronization of

DR and EL at Somanahalli end and Dharmapuri end.

PGCIL (SR-II) Yet to be informed Pending

84/II/15 Tripping of 400kV Bus-1

and connected elements at

400kV Bidadi substation

25-04-2019 at 08:01 hr.Triggering incident was failure of R-ph CB of bus

reactor at 400kV Bidadi. Bus bar protection of Bus-1

operated resulting in the tripping of all elements

connected to Bus-1

1. PGCIL (SR-II) was requested to send the

equipment failure report to CEA.

2.PGCIL (SR-II) is recommended to share the

feedback of OEM regarding decomposition of SF6 gas.

PGCIL (SR-II) Yet to be informed Pending


TPCIL station

25-10-2017 at

19:33 hrs

400 kV TPCIL-Nellore PS line-1 got tripped from

TPCIL end during fault in 400kV Nellore-Nellore PS

line-2. Running units at TPCIL got tripped due to loss

of evacuating line. 400kV Nellore PG - Nellore PS line-

2 and 400kV TPCIL - Nellore PS line-1 were under

shutdown.

TPCIL to configure DEF protection such that it

remains in blocked condition as long as Distance

Protection is active, and becomes active only when

distance protection does not pickup.

TPCIL Review Meeting on 21.12.2018:

It was noted that no TPCIL representatives had come to attend the meeting

Review meetinmg on 27.06.2019:

No representative from the utility attended meeting and it is requested to submit status

regrading the recommendation at athe earliest.

Pending

78/II/2 Tripping of 400 kV Neyveli

TS2Exp -Pugalur line

01-08-2018

at 11:56 hrs

Triggering incident was failure of R-ph tension

insulator string/ flashover in 400 kV Bus-1 at NLC

TS2Exp end. Busbar protection had operated resulting

in tripping of all main breakers connected to 400kV

Bus-1 at Neyveli TS2 Exp. In 400kV NLC TS2Exp -

Pugalur line, fault was sensed in Zone-1, R-N at

Pugalur end resulting in a single phase trip. Direct Trip

was received at Pugalur end due to operation of over

voltage Stg-2 at NLC TS2Exp.

1. NLCIL to furnish a report along with a suitable

SLD on the tripping event explaining the observed

discrepancies [DPR, Z1 operation, instantaneous

operation of OVR-II operation], and remedial action

taken to attend the same.

2. NLCIL to configure DR’s & EL’s of all protection

relays at their NLC TS-IIExp station for all mandated

protections & signals.

NLCIL Review Meeting on 21.12.2018:

NLCIL was asked to furnish the status of implementation of the recommendation

given at the earliest.




Pending

79/II/8 Tripping of 400 kV NLC TS-

2 (Exp) – Pugalur line

10-09-2018 at

20:57 hrs

Line tripped on B-N fault. Auto-reclose was not

attempted at Pugalur end due to DT receipt from NLC

TS2Exp end. At NLC TS2Exp end, V>2 trip was

observed in DR. Analog voltages recorded in DR were

observed to be less than that required for O/V Stage-II

operation.

NLCIL to furnish a detailed report on tripping event

explaining the observed discrepancies , and proper

reasons for tripping of the line considering both the

Main-relays including remedial action taken w.r.t.

healthiness/ replacement of Main protection relays on

400 kV NLC TS2Exp–Pugalur line.

NLCIL Review Meeting on 21.12.2018:

NLCIL was asked to furnish the status of implementation of the recommendation

given at the earliest.


it is requested to submit status regrading the recommendation at athe earliest.

Pending


PS – SGPL line-1

14-11-2018 at

20:20 hrs

Y- ph to earth fault occurred in line due to snapping of

GIS to Air bushing conductor at SGPL switchyard.

The conductor got grounded such that the fault was

being fed by NPS bus and there was earth fault and

broken conductor start at SGPL end. NPS end got

tripped in Zone-2 due to non-receipt of carrier resulting

in a 3-ph trip at NPS. After 500ms, earth fault

occurred at SGPL end resulting in Zone-1 operation

and 3 phase trip. A/R was not attempted at SGPL end

SGPL to examine the reasons for no-operation / failure

of Auto-reclosure from their end for the subject

tripping, and furnish an action taken report detailing

remedial measures taken to PCSC forum.

SGPL Review meetinmg on 27.06.2019:



Pending

80/III/6 Tripping of 400 kV Neyvelli

TS2 (Exp) - Pugalur line

07-11-2018 at

05:50 Hrs

400 kV Neyvelli TS2Exp - Pugalur tripped on

B-phase to ground fault due to DPR, Z1 operation.

Auto-reclose was successful at Pugalur end and the

line tripped at Neyveli TS2Exp end only. Auto-reclose

was not attempted at Neyveli TS-2(Exp) end

NLCIL to furnish a detailed report on the reasons for

A/R non-operation for the subject tripping at their

NLCTS2Exp station including remedial measures

taken to PCSC forum.

NLCIL Review meetinmg on 27.06.2019:



Pending

82/I/13 Tripping of 400kV Kaiga -

Guttur Ckt-2 &

400/220kV ICT-2 at Kaiga

11-02-2019

at 11:46 hrs

Bus-2 at 400kV Kaiga got de-energized due to LBB

operation.

NPCIL (KGS) to sort out the LBB issue in 1 months

time and to furnish a detailed report regarding the issue

in LBB scheme ad how the same has been rectified.

NPCIL (KGS) Review meetinmg on 27.06.2019:



Pending

82/III/11 Tripping of 400 kV KAIGA -

GUTTUR line- 1

16-02-2019

04:27 hrs

R-phase to earth fault occurred in line resulting in

tripping of line. Auto-reclose not attempted at both

ends

NPCIL (KGS) to furnish a report regarding reasons

for failure of A/R at Kaiga end and remedial measures

taken.

NPCIL (KGS) Review meetinmg on 27.06.2019:



Pending

02-04-2016 at

17:08 hrs


S.P.Koil Station of

TANTRANSCO

PendingNPCIL (MAPS) Status revided vide MAPS mail dated 06.12.2016;

1. The settings given by M/s TANTRANSCO were adopted for Main –I & Main- II

relays for both the lines. The same settings were verified to be same. Subsequently

calibrated was done and no drift was observed. --- Completed

2. From May 2016 onwards, the DR, EL and trip report are being sent by mail to

SRLDC, Bengaluru by MAPS. --- Completed

B-phase CT failure occurred in 230 kV S.P.Koil -

MAPS line-1. Busbar protection got operated at

SP.Koil station. All elements except 230kV Oragadam

and 230kV Kalivandapattu got tripped at 230kV

S.P.Koil station. ‘Y’ phase CT and support insulators

also got damaged.

1.MAPS to furnish a detailed report on the tripping of

SP Koil – MAPS lines 1 & 2 at MAPS end with focus

on the correctness of the settings of Main-I & Main-II

relays (for primary & back-up protections) on both the

lines.

2.MAPS to take steps to provide down-loading facility

Others

Annexure-II

Page 28 of 30


KaigaGuttur line-2

11-03-2019 at

01:49hrs

Triggering incident was R-N fault in 400kV

KaigaGuttur line-2. At Kaigaend, fault was sensed in

Zone-1. But LBB of main breakerof the line operated

due to struck breaker conditionof B-phresulting in

tripping of all main CBs of bus-1 and DT sent. Pole

discrepancy operated due to suspected non-opening of

B-ph breaker. At Guttur end, fault was sensed in zone-

2, carrier received and AR attempted. But during AR

operation, line got tripped due to DT receive from other

end.

NPCIL (KGS) is recommended to submit a detailed

report mentioning the cause of tripping and Remedial

measures taken for the same.

NPCIL (KGS) Review meeting on 27.06.2019:



Pending


Kayamkulam –Punnapura-2

24-02-2019 at

03:05hrs

Line tripped on B-phase to earth fault. Auto-reclose

was successful at Punnapura. A/r was not attempted at

Kayamkulam and there was pole discrepancy operation

resulting in tripping of R and Y pole of CB.

It was noted that no representative of NTPC attended

the meeting.

NTPC (Kayamkulam) to furnish detailed report

regarding failure of Auto-reclosure at Kayamkulam

end for Kayamkulam –Punnapura line-2.

NTPC (KYKLM) Review meeting on 27.06.2019:




Trip report for Tripping of 220 kV Kayamkulam –Punnapura-2 submitted , but for

submitting detailed report for Auto-reclosure at Kayamkulam end not operating for

Kayamkulam –Punnapura line-2 , half day shutdown of Kayamkulam –Punnapura

line is required to check reason for failure . May please approve half day outage of

Kayamkulam –Punnapura line and intimate us atleast one day in advance.

Pending


Kayamkulam –Punnapura-2

05-03-2019 at

00:30hrs

220kV Kayamkulam-Punnapura -2 tripped on Zone-1

distance protection due to R-N fault. Auto reclose

operated and successful at Punnapara end but didnot

operate at Kayamkulam end.

It was noted that no representative of NTPC attended

the meeting.

NTPC (Kayamkulam) to furnish detailed report

regarding failure of Auto-reclosure at Kayamkulam

end for Kayamkulam –Punnapura line-2.

NTPC (KYKLM) Review meeting on 27.06.2019:




Trip report for Tripping of 220 kV Kayamkulam –Punnapura-2 submitted , but for

submitting detailed report for Auto-reclosure at Kayamkulam end not operating for

Kayamkulam –Punnapura line-2 , half day shutdown of Kayamkulam –Punnapura

line is required to check reason for failure . May please approve half day outage of

Kayamkulam –Punnapura line and intimate us atleast one day in advance.

Pending


NLC1

Expansion(NLC1EXP)

05-06-2019at 18:51 hr.Triggering incident was failure of Y-phase CT of GT-1 (Generator Transformer) at 400kV NLC1EXP. Bus-1 Bus bar protection operated resulting in the tripping of NLC1EXP U#1 and 400kV NLC1EXP- Nagapattinam line 1. NLCIL to check the healthiness of R & B ph CT of

Unit-1 at NLC TS1(Exp) and if found unhealthy

replace the same alongwith replacement of Y-ph CT.

CT replacement plan and timeframe shall be informed

to SRPC.

2.NLCIL in coordination with PGCIL(SR-II) to

resolve the time syncronisation issues in 230kV NLC

TS1(Exp) – Nagapattinam line.

3. NLCIL was also requested to investigate the reason

of unwarranted DT sent to NLC TS1 (Exp) end from

NLC TS2 end and resolve the same.

NLCIL NLCIL mail dated 09.07.2019:

AT TS2 Side Siemens 7SA52 & Micromho relay are used for distance protection.

During the incident Micromho has sensed the CT blast as a Zone-1 fault and tripped

the feeder. Adt signal was send to TS1 Exp end. The relay will be tested during the

next shut down.

Pending


Dichipally–Ramagundam

line

20-04-2019 at

18:09 hr.

Y phase to Earth fault in the line. Line did not auto-

reclose at Ramagundam end

1. It was noted that no representative of NTPC

(Ramagundam) attended the meeting.

2. NTPC (Ramagundam) to submit a detailed report

regarding non-operation of A/R at Ramagundam end

and Remedial measures taken for the same

NTPC (RMGDM) Yet to be informed Pending

Annexure-II

Page 29 of 30

84/II/20 Tripping of 400kV Neyveli

TS2- Neyveli TS-I (EXP)

and 400/230 kV ICT-1

atNeyvli

07-05-2019 at 20:56 hr.400kV/230kV ICT-1 got tripped on Differential

protection due to failure of R phase bushing on the HV

side. For 400kV Neyveli TS2- Neyveli TS-I (EXP), R

pole breaker at TS1Expgot tripped. TS2 End breaker

tripped on trip command received from TS1 EXP

1. NLCIL to measure the earth resistance of Neyveli

TS-2 SS and submit the same to PCSC forum. NLCIL

to check the healthiness of LAs of ICTs and confirm

proper earthing.

2.It is also recommended to furnish a report on

adequacy of ground wire shielding of switchyard.

3. NLCIL to ensure Time synchronization of relays at

Neyveli TS-2 SS.

NLCIL NLCIL mail dated 09.07.2019:

1) The earth pit resistance of the ICT1 LA was measured as follows.

400 kV side was measured on29-03-19

Rphase - 0.61 ῼ , Y phase - 0.76ῼ , B phase - 0.58 ῼ

230 kV side was measured on 29-03-2019

Rphase - 0.47 ῼ , Y phase - 0.86ῼ , B phase - 0.68ῼ

The resistive leakage current for the LA's was also measured and the readings are as

follows.

400kV side was measured on 29-03-2019 and the values are as follows .

R phase - 73 μA , Y phase 90 μA , B phase - 92 μA .

230kV side was measured on 22-03-2019 and the values are as follows

R phase - 238 μA , Y phase - 330 μA , B phase 401 μA.

After the incident on 07-05-19 the resistive leaksge current was again measured on

13-05-2019 and the values are as follows.

400kV Side

R phase - 91 μA , Y phase - 116 μA , B phase - 105 μA

230 kV side

R phase - 297 μA , Y phase - 318 μA , B phase - 385 μA

2) Time synchronization of one series of relays completed. The time synchronization

of balance relays will be completed by August 2019.

Pending

84/III/1 Tripping of 400kV Kaiga-

Guttur line-1

08-04-2019 at

16:50 hr.

R-phase to earth fault occurred in line. Line did not

attempt auto-reclose at both ends. Pole discrepancy

operation was observed in EL of Kaiga.

It was noted that no representative of NPCIL (Kaiga)

attended the meeting.

NPCIL (KGS) to submit a detailed report mentioning

reason for non-operation of A/R and Remedial

measures taken for the same.

NPCIL (KGS) Yet to be informed Pending


Dichipally–Ramagundam

line

20-04-2019 at

18:09 hr.

Y phase to Earth fault in the line. Line did not auto-

reclose at Ramagundam end


(Ramagundam) attended the meeting.

2.NTPC (Ramagundam) to submit a detailed report

regarding non-operation of A/R at Ramagundam end

and Remedial measures taken for the same.

NTPC(RMGDM) Yet to be informed Pending

84/III/12 Tripping of 400 kV Simhadri-

Kalpakka line-3

12-05-2019 at

18:33 hr.

R-phase to earth fault. Line did not attempt auto-

reclose


(Simhadri) attended the meeting.

2.NTPC (Simhadri) to submit a detailed report

regarding non-operation of A/R at Simhadri end and

Remedial measures taken for the same.

NTPC(Simhadri) Yet to be informed Pending

Annexure-II

Page 30 of 30

Sl.No. Element Name Outage date/time Revival date/time Reason for outage Sender/ Receiver Remedial Measures/ Actions taken Remarks

1 400KV-BPS-TUMKUR-2 17-03-2019/16:17:00 R-Y FAULT KPTCL To-be-discussed

2 400KV/220KV RAMAGUNDAM-ICT-2 05-04-2019/19:56:00 05-04-2019/23:26:00BUS BAR PROTECTION

OPERATEDNTPC To-be-discussed

3 400KV-HINDUJA-KV_KOTA-1 01-05-2019/15:11:00 TRIPPED ON R-N FAULT

HNPCL/ APTRANSCO

[Pending with HNPCL]

APTRANSCO: Feeder tripped on R-

Phase to ground, Zone-1 fault. AR

Successful but after 9Sec DT was

received from Hinduja end.

4400KV-NARNOOR-SRISAILAM_LEFT_BANK-

117-05-2019/14:10:00 17-05-2019/19:48:00 RELAY MALOPERATION

APTRANSCO/ APGENCO

[ Pending with APGENCO]

APTRANSCO: Feeder not tripped at

Narnoor end.

5 220KV-SRISAILAM_Right_BANK-DINDI-2 17-05-2019/11:44:00 17-05-2019/16:33:00 TRIPPED ON R-N FAULT

TSGENCO/ TSTRANSCO

[ Pending with TSGENCO]

TSTRANSCO:

It is 220kV Dindi-Srisailam-2 feeder.

A/R successful at Dindi end.

6 400KV/220KV NELAMANGALA-ICT-3 19-05-2019/16:11:00 19-05-2019/17:03:00 220KV SIDE PROBLEM KPTCL To-be-discussed

7 400KV-HOODY-YELHANKA-1 25-05-2019/20:41:00 transient fault KPTCL/ PGCIL (SR-II) To-be-discussed

8 400KV-BIDADI-TUMKUR-1 29-05-2019/06:11:00 29-05-2019/07:21:00 transient Y-B fault PGCIL(SR-II) To-be-discussed

9 400KV-BIDADI-TUMKUR-2 29-05-2019/06:11:00 29-05-2019/06:57:00 transient Y-B fault PGCIL(SR-II)

PGCIL (SR-II) informed that the line

tripped on Y-B fault due to operation

of Distance protection.PGCIL(SR-II) to inform RM

taken

10 400KV-PAVAGADA-TUMKUR-2 29-05-2019/06:11:00 29-05-2019/15:08:00 transient Y-B fault PGCIL(SR-II)

PGCIL (Sr-II) informed in PRm review

meeting that line tripped on Y-B fault

due to operation of Distance

protection.PGCIL(SR-II) to inform RM

taken

11 HVDC 500KV KOLAR_DC Pole 1 31-05-2019/18:30:00 01-06-2019/00:09:00 DUE TO HVDC LINE FAULT PGCIL (SR-I) To-be-discussed

12 HVDC500KV-TALCHER-KOLAR_DC-1 31-05-2019/18:30:00 31-05-2019/20:14:00 HVDC LINE FAULT PGCIL (SR-I) To-be-discussed

13220KV-SRISAILAM_RIGHT_BANK-

NAGARJUNASAGAR02-06-2019/14:55:00 02-06-2019/15:52:00

TRIPPED ON DISTANCE

PROTECTIONAPGENCO/ TSTRANSCO To-be-discussed

14 400KV-VTPS_IV-SURYAPET-1 02-06-2019/13:15:00 02-06-2019/13:54:00 TRIPPED DUE TO R0N FAULT

APGENCO/ TSTRANSCO


TSTRANSCO:

Fault distance is not in TSTRANSCO

jurisdiction.

15 400KV-RAYALSEEMA TPP-KALIKIRI-2 02-06-2019/19:15:00 02-06-2019/21:20:00 TRIPPED ON B-N FAULT

APGENCO/ APTRANSCO


APTRANSCO: Feeder tripped on B-

Phase to ground, Zcom fault.AR

successful at Kalikiri end.

16 400KV-BTPS-HIRIYUR-2 02-06-2019/18:16:00 TRIPPED ON Y-N FAULT

KPCL/ KPTCL

[ Pending with KPTCL]

KPCL: Line tripped on Zone-2, ""C""

phase to earth.

Remedial Measures: Line Charged on

03.06.2019 at 09:47Hrs from BTPS

end

Pending Remedial Measures/ Actions taken for the Critical Tripping Incidents (as on 12.07.2019)

Annexure-III

Page 1 of 7

17 220KV-ELAPULLY-PALAKKAD(KL)-1 04-06-2019/14:03:00 04-06-2019/14:30:00BUS BAR PROTECTION

OPERATEDKSEBL

KSEBL :

The high impedance BBP at 220kV

Palakkad substation was replaced

with new low impedance GE make

numerical bus bar protection and

commissioned on 30.05.2019. At the

time of commissioning the 220 KV

Bus coupler was not in service. On

04.06.2019, relay team carried out

pre commissioning testing on bus

coupler CT after putting BBP selector

switch to out of service.

While carrying out CT secondary

injection, the relay team had injected

current in O/C and E/F core first. This

had led to operation of earth fault

protection and master trip relay in

bus coupler panel. Trip relay

operation triggered LBB initiation in

numerical bus bar protection. When

relay team injected current in CT

core connected to bus bar relay

without resetting master trip

relay,LBB trip was initiated. As all

element were connected to same

bus, all were tripped.

Annexure-III

Page 2 of 7


OPERATEDKSEBL

KSEBL :


























Annexure-III

Page 3 of 7


OPERATEDKSEBL

KSEBL :


























20 400KV-VTPS_IV-SURYAPET-1 05-06-2019/13:38:00 05-06-2019/14:45:00 DISTANCE PROTECTION APGENCO/ TSTRANSCO

"TSTRANSCO:

Fault distance is not in TSTRANSCO

jurisdiction."

21 HVDC 500KV KOLAR_DC Pole 05-06-2019/19:01:00 05-06-2019/22:08:00due to tripping of all HVDC -

NTPC feeder at NTPC endPGCIL (SR-I) To-be-discussed

22 HVDC500KV-TALCHER-KOLAR_DC-1 05-06-2019/19:01:00 06-06-2019/00:37:00due to tripping of all HVDC -

NTPC feeder at NTPC endPGCIL (SR-I) To-be-discussed

23 220KV-UDUMALPET_TN-IDDUKKI-1 05-06-2019/15:13:00 05-06-2019/18:03:00 R-Y-B FAULT TANTRANSCO/ KSEBL

KSEBL :

Zone 1,Phase

A,PhaseC, Distance trip, 8.962km,

Earth Fault.

TANTRANSCO: Z2 R,B-N 106.3KM &

AR lockoutReason for 3-ph fault? RM

taken?

24 400KV-NEYVELI_TS_II-NEYVELI_TS1_EXP-1 05-06-2019/18:51:00 05-06-2019/20:13:00 CT Blast at NLY1EXP NLCIL To-be-discussed

25 400KV-NELAMANGALA-TALGUPPA-1 05-06-2019/23:23:00H /T TO CONTAIN OVER

VOLTAGRKPTCL To-be-discussed

26 400KV-TALGUPPA-HASSAN-1 05-06-2019/23:59:00 06-06-2019/00:32:00R Phase distance protection

operatedKPTCL/ PGCIL (SR-II) To-be-discussed

Annexure-III

Page 4 of 7

27400KV-NAGAPATTNAM_PS-

NEYVELI_TS1_EXP05-06-2019/18:51:00 05-06-2019/20:57:00 CT Blast at NLY1EXP PGCIL (SR-II)/ NLCIL To-be-discussed

28 132KV-KONAJE-MANJESWAR-1 06-06-2019/05:45:00EARTH FAULT RELAY

OPERATED

KPTCL/ KSEBL

[Pending with KPTCL]

KSEBL:

Feeder not trippped at Manjeswar

end

29 400KV-NARENDRA-GUTTUR-1 06-06-2019/02:01:00 R-Y FAULT KPTCL To-be-discussed

30 400KV-NARENDRA-GUTTUR-2 06-06-2019/02:01:00R PHASE TO NEUTRAL

FAULTKPTCL To-be-discussed

31 400KV/220KV UPCL-ICT-1 06-06-2019/15:41:00DIFFERENTIAL PROTECTION

ACTEDUPCL To-be-discussed

32 400KV-KUDGI_PG-NARENDRA-1 07-06-2019/22:47:00 07-06-2019/23:00:00 Y-N FAULT PGCIL(SR-II) To-be-discussed

33 HVDC 500KV KOLAR_DC Pole 08-06-2019/12:10:00 08-06-2019/13:01:00EXTERNAL PROTECTION

TRIPPGCIL(SR-I) To-be-discussed

34 400KV-BHOOPALAPALLY-WARANGAL-2 08-06-2019/01:35:00 DT RECEIVED PGCIL(SR-I)/ TSGENCO

TSGENCO:

KTPP Unit-II tripped on 08.06.2019@

1:34, Warangal-II feeder tripped on

Overvoltage stage-I @1:35Hrs. The

Unit synchronised wit grid @7:56 Hrs

on 12.06.2019. After getting

clearance, Line charged at 12.06.2019

@9:27Hrs.

"PGCIL (SR-I): 400kV-Warangal-

Bhoopalapalli Line 1&2 both are

holding from Warangal end. Only Line-

2 was tripped at Bhoopalapalli end

due to O/V stg1 at 1:36Hrs

/08.06.2019 but DT not received from

Bhoopalapalli.

Line & PLCC belongs to TSGENCO." Reason for unit tripping?

PLCC healthiness checked by

TSGENCO?

35 400KV-GUTTUR-JINDAL-1 08-06-2019/13:13:00 08-06-2019/15:34:00 TRIPPED ON B-N FAULT JSWEL/ KPTCL To-be-discussed

36 400KV/220KV GUTTUR-ICT-1 11-06-2019/17:24:00 11-06-2019/18:10:00BUS BAR PROTECTION

OPERATEDKPTCL To-be-discussed

37 400KV-DONI-GUTTUR-1 11-06-2019/17:24:00 11-06-2019/18:01:00BUS BAR PROTECTION


38 400KV-GUTTUR-JINDAL-1 11-06-2019/17:24:00 11-06-2019/19:00:00BUS BAR PROTECTION

OPERATEDKPTCL/ JSWEL To-be-discussed

39 400KV-KAIGA-GUTTUR-1 11-06-2019/17:24:00 11-06-2019/20:13:00BUS BAR PROTECTION

OPERATEDNPCIL (KGS)/ KPTCL To-be-discussed

40 400KV-GHANAPUR-RAMAGUNDAM-4 11-06-2019/12:27:00 11-06-2019/13:19:00 Tripped on Y-B Fault TSTRANSCO/ NTPC (RMGD) To-be-discussed

41 400KV-GUTTUR-HIRIYUR-1 11-06-2019/17:24:00 11-06-2019/18:35:00BUS BAR PROTECTION

OPERATEDKPTCL/ PGCIL (Sr-II) To-be-discussed

42 400KV-GUTTUR-HIRIYUR-2 11-06-2019/17:24:00 11-06-2019/18:42:00BUS BAR PROTECTION

OPERATEDKPTCL/ PGCIL (SR-II) To-be-discussed

43 400KV/220KV GUTTUR-ICT-2 11-06-2019/17:24:00 11-06-2019/19:04:00BUS BAR PROTECTION


44 400KV-RAMADUGU-SINGARENI-1 11-06-2019/08:24:00 11-06-2019/12:09:00 DT RECEIVED TSTRANSCO/ TSGENCO To-be-discussed

45 400KV-NELAMANGALA-TALGUPPA-1 12-06-2019/18:24:00 12-06-2019/20:44:00 EMERGENCY WORK KPTCL To-be-discussed

Annexure-III

Page 5 of 7

46 400KV-GUTTUR-HIRIYUR-1 12-06-2019/17:00:00 12-06-2019/17:19:00 DT received from Guttur KPTCL/ PGCIL (SR-II) To-be-discussed

47 400KV-TALGUPPA-HASSAN-1 12-06-2019/14:38:00 12-06-2019/21:31:00 INSULATOR FLASH OVER KPTCL/ PGCIL (SR-II) To-be-discussed

48 HVDC 500KV KOLAR_DC Pole 12-06-2019/12:24:00 12-06-2019/13:13:00DISTURBANCE IN 24V DC

SYSTEMPGCIL (SR-II) To-be-discussed

49 400KV-GMR-VEMAGIRI_AP-2 14-06-2019/09:34:00 14-06-2019/10:06:00 SOTF OPERATED

APTRANSCO/ GMR

[Pending with GMR]


Vemagiri end.

50 400KV/220KV VIJAYAWADA-ICT-1 16-06-2019/06:16:00 16-06-2019/07:54:00CT FLASH OVER at 220 kV

SIDEAPTRANSCO To-be-discussed


SIDEPGCIL (SR-I)

The Element not belongs to

APTRANSCO.

52 220KV-KOTHAGUDEM_TPS-NUNNA_AP-1 16-06-2019/06:16:00 16-06-2019/07:14:00BUS BAR PROTECTION

OPERATEDTSGENCO/ APTRANSCO

APTRANSCO: 100MVA PTR-1 HV B-

Phase CT blasted (connected to

220KV Bus-2) in 220KV Nunna station.

Bus-2 bus bar protection operated

resulting in tripping of elements

connected to 220KV Bus-2. Later a

2nd fault occurred in Bus-1 due to

fault getting extended from CT failure

which inturn resulted in tripping of

elements connected to 220KV Bus-1

(220KV Nunna-KTS line connected to

BUS-1).

TSGENCO: Feeder not tripped at KTPS

end , Bus Bar protection acted at

Nunna end only APTRANSCO to inform the

RM taken?

53 400KV/220KV HOODY-ICT-2 16-06-2019/19:20:00 16-06-2019/20:51:00OVER FLUX PROTECTION

RELAY OPERATEDKPTCL To-be-discussed


SIDEPGCIL (SR-I) To-be-discussed

55 400KV-KAIGA-GUTTUR-2 18-06-2019/02:53:00 R-N FAULT NPCIL(KGS)/ KPTCL To-be-discussed

56 400KV-GOOTY-NELAMANGALA-1 22-06-2019/04:06:00 22-06-2019/05:42:00

r-n fault observed due to

fire in Hiriyur-Nelamangala

1 400KV AC LINE

PGCIL (SR-I)/ KPTCL To-be-discussed

57 400KV-NELAMANGALA-HIRIYUR-1 22-06-2019/04:06:00 22-06-2019/05:53:00

r-n fault observed due to

fire in Hiriyur-Nelamangala

1

KPTCL/ PGCIL (Sr-II) To-be-discussed

58 220KV-AMBEWADI-XELDEM 23-06-2019/16:09:00 TRIPPED ON C-N FAULT KPTCL To-be-discussed

59 400KV/220KV MUNIRABAD-ICT-1 24-06-2019/20:50:00 24-06-2019/21:16:00CT FLASH OVER at 220 kV


60 400KV/220KV MUNIRABAD-ICT-2 24-06-2019/20:50:00 24-06-2019/21:16:00CT FLASH OVER at 220 kV


61400KV-KURNOOL_PG-

NAGARJUNASAGAR_P ..24-06-2019/02:41:00 24-06-2019/03:06:00 RELAY MALOPERATION PGCIL (SR-I) To-be-discussed

62400KV/220KVNAGARJUNASAGAR_PG-ICT-

224-06-2019/21:56:00 24-06-2019/23:23:00

TRIPPED ON BUCCHOLZ

RELAY OPERATIONPGCIL (SR-I) To-be-discussed

Annexure-III

Page 6 of 7

63 220KV-CHILLAKALLU-NARKETPALLI-1 25-06-2019/17:17:00 25-06-2019/17:34:00 TRIPPED ON R-N FAULT

APTRANSCO/ TSTRANSCO

[ Pending with TSTRANSCO]

APTRANSCO: Feeder tripped on R-

Phase to ground, Zone-2 fault. Line

charged after taking permission from

SLDC. Fault distance of 81.68KM falls

in TSTRANSCO juridiction.

64 400KV-BHADRAVATHI-RAMAGUNDAM-1 26-06-2019/16:29:00 26-06-2019/18:35:00 RELAY MALOPERATION NTPC (RMGD)/ WR To-be-discussed

65 400KV-GAZUWAKA-JEYPORE-2 27-06-2019/16:52:00 27-06-2019/17:33:00 TRIPPED ON Y-N FAULT PGCIL (SR-I)/ ER To-be-discussed

66 400KV-KALPAKKA-ASUPAKA-1 27-06-2019/17:20:00 27-06-2019/17:47:00 R-Y FAULT APTRANSCO/ TSTRANSCO To-be-discussed

67 400KV-SALEM-DHARMAPURI-1 29-06-2019/15:43:00 29-06-2019/17:03:00 phase to phase fault PGCIL (SR-II) To-be-discussed

68220KV-NAGARJUNASAGAR_AP-

NAGARJUNASAGAR TS30-06-2019/11:03:00 30-06-2019/11:36:00 TRIPPED ON B-N FAULT APTRANSCO/ TSGENCO


Tallapalli end.

69 220KV-POTHENCODE-TRIVANDRUM-1 04-07-2019/01:18:00 04-07-2019/02:26:00 Insulator flashover in line 2 To-be-discussed

70 132KV-ALAMPUR-APCARBIDE-1 04-07-2019/17:04:00 04-07-2019/17:32:00 TRIPPED ON R-N FAULT To-be-discussed


72 220KV-POTHENCODE-TRIVANDRUM-2 04-07-2019/01:18:00 Insulator flashover in line 2 To-be-discussed


74 132KV-KONAJE-MANJESWAR-1 07-07-2019/12:49:00 DISTANCE PROTECTION To-be-discussed

75 400KV-KALPAKKA-KHAMMAM-1 07-07-2019/18:02:00 07-07-2019/21:55:00 TRIPPED ON B-N FAULT To-be-discussed

76220KV-KOTHAGUDEM_TPS-

LOWER_SILERU-108-07-2019/10:45:00 08-07-2019/11:18:00 TRIPPED ON B-N FAULT To-be-discussed

77 400KV/110KV 09-07-2019/14:47:00 09-07-2019/20:25:00TRIPPED ON BUCCHOLZ

RELAY OPERATIONTo-be-discussed

78 132KV-KODADA-CHIKALLU-1 10-07-2019/23:50:00 TRIPPED ON R-N FAULT To-be-discussed

79 220KV-KOTHAGUDEM_TPS-NUNNA_AP-1 10-07-2019/15:19:00 10-07-2019/15:49:00 Y-N FAULT To-be-discussed

80 220KV-CHILLAKALLU-SURYAPET-1 11-07-2019/00:33:00 11-07-2019/00:57:00 R-N FAULT To-be-discussed

Annexure-III

Page 7 of 7

· ict-3 at nelamangala substation 19-05-2019 at 16:11 hrs as per fir, ict-3 got tripped on...

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