grid occurrences - 58

Agenda for the 58

th Meeting of PCSC scheduled to be held on 18

th October, 2016 Page 1

SOUTHERN REGIONAL POWER COMMITTEE BENGALURU

Agenda for the 58th Meeting of Protection Coordination

Sub-Committee of SRPC to be held on 18th October, 2016 (Tuesday)

1. Introduction

2. Confirmation of Minutes of last PCSC meeting

Confirmation of minutes of 57th Protection Coordination Sub-Committee meeting held on 02.09.2016.

3. Grid Occurrences

3.1 Grid Disturbance (GD), Grid Incidences (GI), and trippings due to failure of Auto-reclosing (A/R), and Mal-operation of PLCC equipment that occurred during the period August-September, 2016 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 in the PCSC forum.

(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 bring/ give 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: (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 16.08.2016 – 15.09.2016 has been brought to Constituents’ notice vide SRPC letters (i) No. SRPC/ SE-III/ PCSC-58/ 2016/6095-99 dated 07.09.2016 and (ii) No. SRPC/ SE-III/ PCSC-58/ 2016/ 6280-89 date 22.09.2016. Non-compliance in this regard would be discussed in the meeting.

4. Submission of reports/compliance by Constituents

4.1 Status of pending Protection Coordination Sub-Committee (PCSC) Recommendations

Status of the pending PCSC recommendations (up to 58th PCSC meeting) given at Annexure-II may please be sent latest by 14.10.2016.

4.2 Remedial measures for "Transmission Elements under Forced Outage"

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

Agenda for the 58

th Meeting of PCSC scheduled to be held on 18

th October, 2016 Page 2

The trip events are based on the daily reports at SRLDC website http://srldc.in/ DailyReport.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), RPC’s are required to obtain from their respective Constituents 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) 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.

The sought status for the month of August, 2016 is still awaited from the following SR-Constituents:

TSGENCO (Hydro), KPTCL, Puducherry, MAPS, NTECL, MEPL & SEL

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

6. 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.

7. Date of next PCSC meeting

The 59th PCSC meeting would be conducted on 30.11.2016 (Tuesday) at 10:30 hrs in the

Conference Hall of SRPC, Bengaluru.

*****

http://srldc.in/%20DailyReport.aspx



Grid Occurrences - 58

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 Kalamasherisub station of KSEB

23-08-2016 at 11:20 hrs

Triggering incident was conductor snapping in 110kV Kalamashery-Kaloor feeder

Load loss : 500MW

GD-1

2

Complete outage of 220kV Nagjheri power station of KPCL.

31-08-2016 at 12:47hrs

Bus dead occurred at 220kV Nagjheri Power station due to tripping of evecuating lines.

GD-1

3

Complete outage of Kadra power station of KPCL

06-09-2016at 14:40 hrs

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

GD-1

4

Complete outage at 220kV Chitoor substation

09-09-2016at 10:40 hrs

220kV Bus sectionalizer B-Ph Bus jumper towards Kalikiri feeder got snapped creating a bus fault at 220kV Chittoor substation

GD-1

5

Complete outage at Sharavathy Tail Race power Station

09-09-2016 at 11:19 hrs

Spurious operation of LBB protection of line feeder had led to tripping of 220kV bus at Sharavathy tail race power station.

GD-1

6

Disturbance in Kerala system

12-09-2016 at 14:47 hrs

Partial disturbance occurred in central Kerala grid due to overloading and tripping of 220kV lines. Loss of infeed to 220kV Kalamashery, 220kV Bramapuram, 220KV Ambalamugal, 220 Pallom& 220kV Kochi. Generation at Neriamangalam, Panniar, Chengulam and Pallivasal also got affected during the incident.

Load loss: 690 MW Gen Loss: 300MW

GD-1

Annexure-I

Page 1 of 4

7

Complete outage at Varahi hydro Power Station

15-09-2016 at 14:06 hrs

LBB protection operated and caused bus shut down at Varahi.

GD-1

II. Details of Grid incidents:

Sl. No.

Details of Event Date & Time Reason Category

1 Tripping of 400/220 kV ICT-2 at N’Sagar

09-08-2016at 9:31 hrs

ICT -2 tripped due to mal-operation of Y-Phase PRD

2 Tripping of 400/220kV ICT-2 at 400kV Guttur

13-08-2016 at 09:15 hrs

ICT-2 got tripped without any relay operation

3 Tripping of 400kV Sriperambadur-SV.Chatram line

14-08-2016 at 13:49 hrs

line tripped at Sriperambadur end only on operation of directional earth fault protection

4

Tripping of 400kV NCTPS-Vallur line – 2

21-08-2016at 7:15 hrs& 20:35 hrs

Direct trip was sent from NCTPS to Vallur which led to tripping of breaker at Vallur end

5

Tripping of 400kV Neyveli TS2-Pugalur line and 400kV Neyveli TS2-Neyveli EXP line

21-08-2016 at 10:35 hrs

Failure of Y-Ph tension insulator of tie feeder bay at Neyveli TS2. Neyveli-Pugalur line tripped due to over voltage at Neyveli TS2 and direct trip was received at Pugalur.

6

Tripping of 220kV lines and ICT’s at 220kV Chikampalli substation of APTRANSCO

22-08-2016 at 3:15 hrs

Failure of B-phase CT had occurred in 220kV Chinakampalli-Kalikiri feeder at Chinakampalli end.

7 Multiple tripping at 400kV Neyveli TS-II

22-08-2016at 06:14 hrs

Bus bar protection of bus-2 operated at NLC-II due maloperation CT selection relay of NLC2-NLC2 expansion feeder

8 Tripping of HVDC Gazuwaka Pole-1

23-08-2016 at 13:08 hrs

Non-opertion of B-phase OLTC tap of Pole-2 had led to undesired tripping of east filters and Pole-1

9

Tripping of 400kV Jamalamadugu-Uruvakonda and 400kV Jamallamadugu-Kurnool (AP)-2 lines

28-08-2016at 2:06 hrs

Both lines got tripped on operation of over-voltage stage-1.

10

Tripping of 400kV Krishnapatnam-Chitoor line-1

29-08-2016 at 21:46 hrs

R-phase to earth fault had occurred in line. Auto reclose was successful at Chitoor end and was not successful at Krishnapatnam

11 Tripping of 400/ 110kV ICT-4 at Sunguvarchatran

30-08-2016 at 12:06hrs

Tripped due to LV sideBph.LA failure.

Annexure-I

Page 2 of 4

12 Tripping of 400kV Kayathar-Karaikudi line-2

01-09-2016at 2:15 hrs

line tripped on operation of over voltage protection at Karaikudi end and direct trip was received at Kayathar

13

Tripping of 400kV Raichur-Gooty line-1 and Gooty-Tumkur line-2

01-09-2016at 5:17 hrs

400kV Gooty-Raichur line tripped at gooty end only and was holding from Raichur. 400kV Gooty-Tumkur line-2 tripped on over voltage.

14

Tripping of 400kV Gooty-Tumkur line-2

02-09-2016 at 21:56 hrs

line tripped on operation of over-voltage protection at Gooty end and diect trip was received at Tumkur

15

Tripping of 220kV Sabarigiri-Theni line

03-09-2016 at 10:21hrs

Line tripped on Ground Over current and backup protn. At Theni end distance protection Zone-2 operated.

16

Multiple tripping at 400 kV KalpakkaStation

06-09-2016 at 16:43 Hrs

Y-Pole breaker of Bus reactor-3 got failed during its charging. This resulted in a bus fault in 400kV bus-1 resulting in tripping of 400kV elements connected to Bus-1

17

Multiple tripping at 230kV Alamathy Station

14-09-2016 at 11:13Hrs

Bus Bar Protection (Zone2) of 230kV Bus-B got operated at Alamathy Station during fault in 230kV Alamathy-Koratur feeder.

15-09-2016 at 22:14 hrs

Bus Bar Protection (Zone1) of 230kV Bus-A got operated at Alamathy Station during fault in 230kV Alamathy-OPG-1 feeder.

18

Tripping of 765kV Solapur-Raichur line

14-09-2016 at 15:43 hrs

line tripped at Solapur end and was holding from Raichur end.

19

Tripping of 400kV Madurai-Karaikudi line

hrs 15-09-2016at 03:02hrs

line tripped on operation of over-stage stage-1 at karaikudi and direct trip was received at Madurai

III. Failure or non-operation of Auto reclose during transient fault

Sl. No.

Element Date & Time Reason

Category

1

Tripping of 220kV Ambewadi-Ponda line-1

12:37 hrs on 15-08- 2016

line tripped due to transient fault in B-phase. Auto reclose is not enabled

13:43 hrs on 19-08-2016

2 Tripping of 220 kVChikodi- Talandage

25-08-2016 at hrs

R-phase to earth fault. Line auto-reclosed at Chikodi and did not reclose at Talandage.

Annexure-I

Page 3 of 4

3 Tripping of 400kV Krishnapatnam-Chitoor line-1

29-08-2016 at 21:46 hrs

R-phase to earth fault had occurred in line. Auto reclose was successful at Chitoor end and was not successful at Krishnapatnam

4 Tripping of 400kV N’Sager-Cudappah line-2

06-09-2016at 19:52 hrs

line tripped on a Y-phase to earth fault. Line auto-reclosed at N’sagar end and failed to reclose at Cudappah.

5 Tripping of 220kV Ambewadi-Ponda line-1

07-09-2016 at 13:32 hrs

line tripped on a B-phase to earth fault. Auto-reclose is not enabled for the line

6

Tripping of 220kV Yerandahalli-Hosur line

08-09-2016 at 14:16 hrs

line tripped on R-phase to earth fault. Attempt for auto reclose could not be established from D.R of Hosur end. Optimo distance relay at Yerandahalli end had sensed Zone-3 which seems to be mal-operation

7

Tripping of 400kV Khammam-KTPS line-1

13-09-2016 at 19:15 hrs

line tripped on R-phase to earth fault. Line auto-reclosed at Khammam end and did not auto-reclose at KTPS end due to direct trip receive

IV. Trippings due to PLCC mal-operation

Sl. No.

Element Date & Time Reason

Category

1 Tripping of 400kV Ramagundam-Warangal line

12-09-2016at 12:03 hrs

Line tripped on direct trip receive at Ranagundam end and line was holding from Warangal end.

*****

Annexure-I

Page 4 of 4

Meeting

No /

Index

Details of Event Date &

Time

Reason PCSC Recommendations Utility responsible for

Implementation

Status of Recommendations

as on 30.09.2016

Remarks

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

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.

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 Yet to be informed Pending

21-02-2015

at

00:49 hrs

Y-Ph Metering PT failed at 220KV

Ragulapadu Substation. Fault got cleared by

tripping of lines from remote ends.

1. APTRANSCO to furnish the remedial measures taken in consequent

to the tripping incident along with the status of bus bar protection and

bus coupler at Regulapadu S/s.

2. A/R feature to be enabled on Regulapadu – Alipuira 220 kV inter-

state line.

APTRANSCO Mail received on 27-05-2015:

1)Failed metering PT was replaced with new PT.

2) 220kV Ragulapadu is a single bus system. Hence there is no provision

for bus coupler at Ragulapadu SS.

Mail received on 24-06-2015:

APTRANSCO Vide Ltr. Dt. 23/06/2015, requested KPTCL to furnish the

details of available tele protection equipments and details of the

equipments going to be procure for enabling the carrier aided protection

on 220KV Ragulapadu-Alipura line. Based on the KPTCL information

we will take further necessary action.

Mail recieved on 22-08-2015:

APTRANSCOhas planned to commission ABB make ETL-41 type PLCC

terminal along with NSD-50 type protection coupler at Ragulapadu end

towards Alipura. vide our Ltr Dt 23-07-2015, it is requested KPTCL to

arrange ABB make ETL-41 cabinet with NSD-50 type protection coupler

for establishing PLC communication between Alipura- Ragulapadu.

KPTCL Mail recieved on 23-01-2016:

KPTCL is ready with ETL-41 cabinet with NSD-50 type protection

coupler at Alipur end.

APTRANSCO mail received on 24-02-2016:

Protection coupler equipment is ready at Ragulapadu end. Wave trap

errection is pending at Ragulapadu end. To maintain the ground

clearenace structural modification works are going on for errection of

wave trap.

APTRANSCO mail dated on 22-06-2016:


errection works are going on.

Pending42/II/3

Pending Implementation of PCSC Recommendations (up to 57th Meeting)

Complete outage of 220kV

Yerraguntla substation and

tripping of running Units at

Rayalaseema TPS

52/I/2

(GD)

PendingMail received on 27-07-2016:

1.The drop out relays of reducer oil pumps time setting was increased for

all mills.So there will not be any trip under transient low voltage

condition.----Complied

2.The recommendation regarding 2 sec time delay will be implemented

during unit shut down and will be intimated immediately after

implementation.------Pending

APGENCO 1. APGENCO to check associated logic for lube oil pump for correct

operation under transient low voltage conditions at Rayalaseema TPS,

Unit-1.

2. APGENCO to keep appropriate time delay/ fault ride through delay

(typically 2 sec) in VFD speed sensor relay at all its generating Units

including Rayalaseema TPS Units.

HV B-Ph Current transformer of 100MVA

Power Transformer -1 failed resulting into a

bus fault on 220KV Bus-1. Unit-1 and Unit-

5 at RYTPS tripped during the fault at

Yerraguntla substation

21-02-2016

at 10:39 hrs

Andhra Pradesh

Outage at

Regulapadu

station of

APTRANSCO

Annexure-II

Page 1 of 26

44/III/2 Tripping of 400kV

Ghanapur-Mamidapalli

line

15-04-2015

at 2:03 hrs

Line tripped at Mamidapalli end only and

was holding at Ghanapur. Overvoltage

protection had operated at Mamidapalli

TSTRANSCO to make DR functional at Mamidipalli TSTRANSCO TSTRANSCO informed vide their mail dated 24.06.15 that the existing

relays would be replaced with numerical relays in DPR works.

Pending

55/II/21 Multiple tripping at

Vijayawada TPS

(Gen Loss : 750 MW)

21-02-2015

at

00:49 hrs

Y-Ph Metering PT failed at 220KV

Ragulapadu Substation. Fault got cleared by

tripping of lines from remote ends.

1. APTRANSCO to furnish the remedial measures taken in consequent

to the tripping incident along with the status of bus bar protection and

bus coupler at Regulapadu S/s.

2. A/R feature to be enabled on Regulapadu – Alipuira 220 kV inter-

state line.

APTRANSCO

line tripped on operation of line reactor

protection at Sriperambadur end and direct

trip was sent to Chitoor. Buchholz relay of

line reactor of 400kV Chitoor-

Sriperambadur got operated at Sriperabadur

end.

01-02-2016

at 9:55 hrs

Telangana


1)Failed metering PT was replaced with new PT.

2) 220kV Ragulapadu is a single bus system. Hence there is no provision

for bus coupler at Ragulapadu SS.


APTRANSCO Vide Ltr. Dt. 23/06/2015, requested KPTCL to furnish the

details of available tele protection equipments and details of the

equipments going to be procure for enabling the carrier aided protection

on 220KV Ragulapadu-Alipura line. Based on the KPTCL information

we will take further necessary action.


APTRANSCOhas planned to commission ABB make ETL-41 type PLCC

terminal along with NSD-50 type protection coupler at Ragulapadu end

towards Alipura. vide our Ltr Dt 23-07-2015, it is requested KPTCL to

arrange ABB make ETL-41 cabinet with NSD-50 type protection coupler

for establishing PLC communication between Alipura- Ragulapadu.


KPTCL is ready with ETL-41 cabinet with NSD-50 type protection

coupler at Alipur end.

APTRANSCO mail received on 24-02-2016:


errection is pending at Ragulapadu end. To maintain the ground

clearenace structural modification works are going on for errection of

wave trap.



errection works are going on.

Pending

1. APTRANSCO to furnish SLD of 220/132 kV Chittoor SS,

2. APTRANSCO to confirm whether 220 kV side is on single-bus

operation with only one main-zone. If so, APTRANSCO shall examine

the feasibility of providing split-bus operation or multiple main-zones

for bus bar protection, and take necessary steps to implement it.

APTRANSCO

Tripping of 400 kV

Chittoor-Sriperambadur line

42/II/3

Pending

Outage at

Regulapadu

station of

APTRANSCO

52/II/1 APTRANCO to take steps to ensure that DR and EL are configured for

recording DT receipt event at their

400 kV Chittoor substation.

APTRANSCO APTRANSCO mail dated on 22-06-2016:

The compliance report will be furnished after completion of

configuration.


The retrofiting works are going on for automation of substation and will

be atteneded under these works.

Pending

02-06-2016

at 00:41 hrs

Triggering incident was R-phase to earth

fault in 220 kV Vijayawada TPS - Podili

line. Breaker at Vijayawada TPS end was

under lockout and this resulted in operation

of LBB protection and further leading to

tripping of 220 kV Bus-1 at Vijayawada

TPS

Tripping of 220kV Chittoor-

Tiruvalam

56/II/13

50/II/14

LBB protection got operated for 400/220kV

ICT-2 breaker which had resulted in tripping

of 220kV Bus-2 at 220kV Gooty Substation

24-06-2016

at 16:04 hrs

Tripping at 220kV Gooty

Substation of

APTRANSCO

1.APGENCO to ensure full-fledged redundancy of supply to the

auxiliaries of all Units in the to-be-reviewed LT arrangement by (i)

ensuring that each Unit’s auxiliaries are fed from two Station

Transformers connected to different buses, or (ii) any other better

design.

2.APGENCO to keep LBB time setting as 200 msec at their

Vijayawada TPS.

3.APTRANSCO to take steps to provide PLCC carrier communication

& Auto-reclosure facility between VTPS and Podili SS. ---------

Completed

APGENCO/

APTRANSCO


PLCC carrier aided protection wasprovided.

Pending

1. SLD furnished vide APTRANSCO mail dated 22-06-2016.

--- Completed.

2. APTRANSCO vide their mail dated 24.02.2016 that 220KV chittoor

substation is a old 220KV substation with single bus operation. Bus bar

protection has both main & checkzone are in service. ----- Pending.


220KV chittoor substation is a old substation with single bus operation.

Both main & checkzone are in service in Bus bar protection. The split bus

operation is not possible as there is place constraint for extension of the

swithyard. (Substation was located at the corner of the site).

PendingDuring testing of DC earth leakage, DC got

extended to bus bar protection relay. Hence

bus bar protection operated and tripped the

220KV BUS connected transformers and

feeders.

18-11-2015

at 11:20 hrs

1.APTRANSCO to check the healthiness of the connecting cable

between Gooty (PGCIL) and Gooty (APTRANSCO), and replace it, if

required.

2.APTRANSCO to ensure that the distributed architecture employed in

implementing busbar protection at their Gooty 220 kV SS does not

introduce any unwarranted delays in transmitting the triggering signals

to the Central Unit.

APTRANSCO APTRANSCO mail dated on 31-08-2016:

To avoid the unwanted malopeartions due to the external LBB trip

initiation from PGCIL, Vide letter Dt: 04-08-2016, APTRANSCO has

requsted the PGCIL to arrange the Master trip relay and breaker contacts

of ICT-1 &2 LV side to enable the internal LBB feature in the Busbar

protection scheme at 220kV Gooty Switching station. Waiting for the

PGCIL response.

Annexure-II

Page 2 of 26

48/III/4 Tripping of 220kV Gajwel-

Shankarapally line

20-09-2015

at 2:24 hrs

line tripped at Gajwel end on R-Phase to

ground fault. Reason for non-auto reclose

could be established as DR and EL of both

ends were not furnished

TSTRANSCO to furnish a detailed report on the tripping event along

with remedial measures taken to PCSC forum.

TSTRANSCO Yet to be informed Pending

51/IV/1 Tripping of 400kV Gajwel-

Hyderabad

29-12-2015

at 6:11 hrs

and 7:11 hrs

Line tripped at Gajwel end only due to

suspected PLCC mal-operation at Gajwel

end

TSTRANSCO to check the integrity of all DR’s and EL’s, and sort out

communication related issues at 400 kV Gajwel SS.


52/I/6 Complete outage of 220kV

Malyalapalli station of

TSTRANSCO

10-03-2016at

18:41 Hrs

CT failure occurred in 220kV Ramagundam-

Malyalapalli line-1 at Malyalapalli end. The

CT failure resulted into a Bus fault. All

220kV lines and transformers at

Malyalapalli station tripped during the

incident.

TSTRANSCO to furnish the Equipment Failure Report for the R-ph

CT blast to Power System Engg & Technolgy Divison (PSETD) of

Central Electricity Authority with a copy marked to SRPC.


54/II/2 Tripping of 400kV

Shankarapalli -

Mamidapalli line

04-04-2016

at 00:03 hrs

Y-Phase CT failure had occurred in 400kV

Shankarapalli-Mamidapalli line at

Mamidipally end.

1.TSTRANSCO to revise A/R dead-time on 400 kV Shankarapalli –

Mamidipalli to 1 sec at both ends.

2.TSTRANSCO to furnish Equipment Failure Report of Y-ph CT blast

to CEA with a copy marked to SRPC.



Sedam Substation of

KPTCL.

19-06-2016

at 15:27hrs

220kV Sedam-Humnabad-2 tripped at

Sedam on Distance protection, Zone-2.

Sedam-RTPS-1 &2 lines tripped at RTPS

end only. 220kV Tandoor inter-state line

was hand tripped due to incoming supply

failure

1.TSTRANSCO to revise distance relay settings at Tandur end for

Tadur Sedam S/C line appropriately so that mal-operations due to it are

eliminated.

2.TSTRANSCO to resolve issues in providing DR & EL of Tandur end

relays by 15.08.2016.



Shankarapalli-Mamidapalli

line-2

03-06-2016

at 20:58 hrs

Line tripped on R-phase to earth fault. Line

did not auto-reclose.

1.TSTRANSCO to take steps to furnish (upload) tripping files

(FIR/DR/EL/TR) for the lines involving their substations in time

(within one day of the occurrence of the tripping event) as per IEGC

Regulation 5.2 (r).

2.TSTRANSCO to put A/R into service on 400 kV Shankarapalli –

Mamidipalli line with immediate effect.


TSTRANSCO to furnish a detailed report on the tripping event along

with remedial measures taken to PCSC forum.

Tripping of 400kV

Nagarjunsagar-

Mahboobnagar line

TSTRANSCO07-09-2015

at 2:58 hrs

Line tripped on operation of over-voltage

protection at Mahboobnagar and direct trip

received at N’sagar station. DT receive was

observed in DR and EL of N’sagar station.

D.R/EL of Mahboobnagar was not furnished

to validate the overvoltage tripping

Pending48/II/5 Yet to be informed

Annexure-II

Page 3 of 26


1. e- Tender folated for the retrofit of existing static relays with

Numerical version for lines M.nagar,M.bad,ICT-1 & 2 -Technical Bid &

Price bid opened . Bid evaluation and approval to place P.O. is in

progress.

2. Retrofit of existing bus bar (CAG-34) with numerical version -

Budgetetory offers obtained and is in process.

3. Order placed on M/s Siemens to replace relays. The work will be

completed by May - 2015.


1. Retrofit of existing static relays with Numerical version for lines

M.nagar, M.bad and ICT- 1 & 2 -- Inspection of the Numerical relays at

M/s Siemens works completed on 11-06-2015 and Dispatch clearance has

been issued. Materials received.

2. Retrofit of existing bus bar (CAG-34) with numerical version –

Budgetary offers obtained and is under process.


1. Replacement of Old electromagnetic relays with Numerical relays has

been completed for RTPS-BTPS line & commissioned on 18.03.2014.

Raichur-PG1 & Raichur-PG2 lines have already retrofitted with numerical

relays.

The retrofitting of electromechanical relays with Numerical version for

ICT-1, ICT-2 and Munirabad line has been completed.

Retrofitting work for Mehaboobnagar line is pending. Awaiting for line

shutdown.

2. Job order placed on 26.06.2015 on M/s Alstom T&D India Ltd.

Chennai for retrofitting of relays for all 220kV lines at RTPS.

3. Retrofit of existing bus bar(CAG-34) with numerical version–


Mail recieved on 21-10-2015 and 23-11-2015:

1) Replacement of Old electromagnetic relays with Numerical relays has

been completed for RTPS-BTPS line & commissioned on 18.03.2014.

Raichur-PG1 & Raichur-PG2 lines have already retrofitted with numerical

relays.

The retrofitting of electromechanical relays with Numerical version for the

following lines/ICTs have been completed/commissioned as follows:

a) ICT-2 –Commissioned on 01-08-2015

b) ICT-1 ---Commissioned on 08-08-2015

c) Munirabad line--- Commissioned on 16-08-2015.

d) Mehaboobnagar line-- Commissioned on 09-09-2015.

2. Job order placed on 26.06.2015 on M/s Alstom T&D India Ltd.

Chennai for retrofitting of relays for all 220kV lines at RTPS.

3. Retrofit of existing bus bar(CAG-34) with numerical version–


PendingRTPS Tripping incidents

and the Spl meeting held at

RTPS on 13th and 14th

March 2014

30/I/A

Karnataka

KPCLThe PCSC forum recommended for replacement of existing

electromechanical relays with Numerical relays. Spl meeting held at RTPS on 13

th and 14

th

March 2014

Mar-14

Annexure-II

Page 4 of 26

GD-1 at Kadra and

Kodasalli hydro power

station

GD-1 at 220kV Kadra

power Station of KPCL

ICT tripped due to operation of Over current

and Earth fault relay

14-01-2015

at 1:09

hrs

41/I/1

Tripping of

400/220kV ICT-1 at

BTPS

43/II/14

16-02-2015

at 12:56 hrs

38/GD/3.5 A fault had occurred in 220 kV Kadra and

Kodasalli. As A result, de-energization of

220kV bus occurred at Kadra and Kodasalli.

13-11-2014

at 19:31hrs


1) e-NIT floated on 28.07.2014 for procurement of Numerical distance

relays & GPS. As there is change in scope of work and quantity of relays

by more than 25%, which is not permitted as per KTPP act. Hence, tender

cancelled and refloated on 05.05.2015 with revised scope of work and

revised PQR.

2. However, as per the recommendations of PSAG, Relays were

temporarily rearranged, replaced and wired up. testing & commissioning

shall be completed with the assistance of KPTCL.


1. Cover -1 of the bid is scheduled for open eing on 25.06.2015.

2. As per the recommendations of PSAG, Relays were temporarily

rearranged. testing & commissioning completed with the assistance of

KPTCL.


NIT floated on 5.5.15 through e-portal. Bid evaluation completed.

Obtaining of Administration approval to place P.O is in progress.

However, as per therecommendationsof PSAG-10, Relays

weretemporarilyrearranged.Testing & commissioning completed with the

assistanceofKPTCL.


NIT floated on 5.5.15 through e-portal. Bid evaluation completed. LOA's

issued to M/s Schneider Electric Infrastructure Ltd. on 08.10.2015.


LOA's issued to M/s Schneider Electric Infrastructure Ltd. on 08.10.2015.

Engineering work is in progress.

Status informed during Special Meeting held on 03.06.2016:

LOA’s issued to M/s Schneider on 08.10.2015. Inspection of relays

completed and received at site. DI issued for all balance materials except

furnitures.

PendingKPCL1. The PCSC forum requested KPCL to speed up the installation of

Numerical Distance Protection relay in Kadra –Kaiga and

Kodasalli –Kaiga.

2. The PCSC forum requested KPCL to submit the implementation

status of PSAG-10 recommendations within a week’s time.

KPCL


1. Main-2 relays already installed and commissioned.

2. DC fuses are intact. Till date no such incidence occurred.

3. Possibility of DC-1 & DC-2 arrangement and splitting of DC will be

reviewed.

Mail received on 07-07-2015 , 21-10-2015 and 23-11-2015:

1. Completed.

2. Completed.

3. Possibility of DC-1 & DC-2 arrangement and splitting of DC will be

reviewed.

Triggering incident was B-phase to earth

fault had occurred in 220kV Kadra-

Kodasalli line. Line tripped from Kodasalli

end only. 220kV Kaiga-Kadra tripped in

Zone-3 from Kaiga end. Tripping of

evacuating lines caused bus shut down at

Kadra hydro station.

1. KPCL to make functional the Main2 (EPAC) relay with the help

of KPTCL at the earliest.

2. KPCL to investigate the reason for DC fuse fail during transient

fault in 220kV Kadra-Kodasalli line including the testing/ checking of

DC supply cables, breaker control cables, and trip coils.

3. KPCL to ensure supply for Main-1& Main-2 protections, Trip

Coils (TC1, TC2) from separate battery banks.

KPCL

PendingKPCL vide their mail dated 07.07.2015 informed that revised relay

settings would be incorporated in co-ordination with KPTCL.


Revised relay settings are awaited from KPTCL.

Revised relay settings furnished by KPTCL will be incorporated in co-

ordination with KPTCL shortly.

KPCL to check the possibility of providing line differential protection

between RTPS and Yermarus stations.

Pending

Annexure-II

Page 5 of 26

ICT tripped due to operation of Over current

and Earth fault relay

14-01-2015

at 1:09

hrs

Tripping of

400/220kV ICT-1 at

BTPS

43/II/14 KPCL PendingKPCL vide their mail dated 07.07.2015 informed that revised relay

settings would be incorporated in co-ordination with KPTCL.


Revised relay settings are awaited from KPTCL.

Revised relay settings furnished by KPTCL will be incorporated in co-

ordination with KPTCL shortly.

KPCL to check the possibility of providing line differential protection

between RTPS and Yermarus stations.

Annexure-II

Page 6 of 26

49/II/15 Trippings at Raichur TPS 12-11-2015

at 00:30 hrs

Running Unit-4, 5 and Unit-8 and 400kV

RTPS-Yeramaras TPS feeder got tripped

due to de-energization of both 400kV Bus-

1&2 at Raichur TPS

1. KPCL to carry out hot-line washing of RTPS-connected lines

regularly to avoid trippings due to fog and dust.

2. KPCL may see the feasibility of providing breaker flashover

protection at RTPS, and implement the same if possible.

KPCL Status informed during Special Meeting held on 03.06.2016:

1. Hot line washing was done previously.tender process is on for silicon

coating of insulators.

Pending

54/II/4 Tripping of 400 kV Raichur

TPS-Mahboobnagar line

05-04-2016

at 10:23 hrs

Line tripped on operation of Backup

impedance protection of line reactor. Direct

trip was received at Mahboobnagar end.

KPCL to keep the functioning of the concerned electro-mechanical

back-up impedance protection relay under observation, and replace it

with a spare at the earliest.

KPCL Yet to be informed Pending

54/II/9 Tripping of 400kV Raichur

TPS Bus-2

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

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

1. KPCL to revise the settings of GT’s back-up O/C and E/F

protections considering their individual contribution to solid bus fault at

220 kV bus of Nagjheri PH.

2. KPCL to upload/ make available various tripping files

(FIR/DR/EL/TR) for all tripping involving their stations in compliance

of IEGC Regulation 5.2 (r).

54/I/4 Tripping of Nagjheri

Generators

220 kV Nagjheri - Bidnal line tripped on B-

E fault at 12:28 Hrs. At the same time, five

running generating units (1, 2, 3, 4 & 6) at

Nagjheri tripped on operation of Generator

Transformer’s back-up Over Current &

Earth Fault protection.

46/II/21 KPCL07-06-2015

at 01:35 hrs

Trippings at 220kV Raichur

TPS

Yet to be informed Pending 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.

KPCL


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.


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 facilitate to put both buses in service.

Time required for this retrofit is around 90days . However, this work will

be taken up only after retrofitting of electromagnetic relays with numerical

relays for Main-2 protection of all 220kV lines, for which work is in

progress.

13-04-2016

at 21:12 hrs

PendingYet to be informed14-04-2016

at 12:29 hrs

Annexure-II

Page 7 of 26

55/II/1


Sedam Substation of

KPTCL.

19-06-2016

at 15:27hrs






failure

KPCL to disable GFC protection on all lines emanating from their

generating stations.


57/II/3 Tripping of 400/220 kV

ICT-2 at Raichur TPS

07-07-2016

at 3:32 hrs

ICT-2 tripped on operation 400/220KV ICT-

2 was tripped on operation of 220KV side

Instantaneous over current protection during

B-phase to earth fault in 220kV RTPS-

Sedam-II line.

KPCL to review appropriately the high-set of ICT’s back-up O/C

protection at their 220 kV RTPS so that they do not operate for a normal

through fault.


Multiple tripping at 400 kV

Raichur TPS Station

01-05-2016

at 21:44 Hrs

Triggering incident was failure of R-phase

CT of 400/220kV ICT-1. 400kV YTPS-

RTPS line got tripped from YTPS end.

400kV RTPS-Mehaboobnagar line tripped

on a B-phase to earth fault.

GD-1 at Mahalingapura

Substation of KPTCL

1. PCSC forum recommended KPTCL to replace the old static

distance protection relays with numerical relays.

2. PCSC forum also requested KPTCL to provide a broken conductor

alarm indication in Control Room.

3. Standing instruction needed to be given to the all substation

personnel for not changing the relay settings without approval of

RT/MRT wing.

Tripping of Units at

Raichur TPS

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

55/II/19 Tripping of 400kV Bellary

TPS-Yeramarus TPS line

and 400kVYeramarus TPS -

Raichur TPS line

31-05-2016

at 17:21 hrs

Direct Trip was sent from YTPS to RTPS

and BTPS

38/GD/3.1

54/II/13

25-10-2014

15-04-2016

at 15:36 hrs

1.KPCL to enable zero-sequence compensation feature, if not already

done, in all differential relays of transformers at RTPS.

2.KPCL to examine in detail the reasons for SOTF operation at RTPS

end for the fault on RTPS-Veltoor line, and if required relay

(configuration) settings at RTPS end may be suitably got revised with

the help of their OEM.

3.KPCL to take steps to enable auto-reclose for the Tie-CB’s in the dias

containing Munirabad and Veltoor (Mehboobnagar) at RTPS.

1.KPCL to properly configure the distance relays at YTPS end on both

YTPS – BTPS line and YTPS-RTPS line with specific focus on reaches

and timings of Zone-2, Zone-3, and Zone-4 (reverse).

2.KPCL to ensure the healthiness of Direct Trip circuits and relay coils

at YTPS.

3.KPCL to ensure time sync of DR’s and EL’s at YTPS with GPS.

Pending

KPCL

Yet to be informed

Fault had occurred in 220kV

Mahalingapura-Narendra line-2. Due to the

failure of relay operation at Mahalingapura,

breakers at remote end tripped which

resulted in bus dead condition.

Pending

Pending

Mail received on 27-05-2015 (KPTCL) & 29-07-2015:

1.Existing Back up relays will be replaced by numerical type distance

relays.Procurement is in tendering stage.

2. Completed.

3. Completed.


1. Existing back up relays will be replaced by Main-2 protection. LOI

issued M/s Alstom for taking up the works.

KPTCL Mail Recieved dated 25-05-2016:

Under the Scope of R&U. The work will be taken up by M/s Alstom

shortly.

KPTCL

Yet to be informed

KPCL

Yet to be informed

Pending

Annexure-II

Page 8 of 26

GD-1 at Mahalingapura

Substation of KPTCL

1. PCSC forum recommended KPTCL to replace the old static

distance protection relays with numerical relays.

2. PCSC forum also requested KPTCL to provide a broken conductor

alarm indication in Control Room.

3. Standing instruction needed to be given to the all substation

personnel for not changing the relay settings without approval of

RT/MRT wing.

38/GD/3.1 25-10-2014 PendingFault had occurred in 220kV

Mahalingapura-Narendra line-2. Due to the

failure of relay operation at Mahalingapura,

breakers at remote end tripped which

resulted in bus dead condition.


1.Existing Back up relays will be replaced by numerical type distance

relays.Procurement is in tendering stage.

2. Completed.

3. Completed.


1. Existing back up relays will be replaced by Main-2 protection. LOI

issued M/s Alstom for taking up the works.


Under the Scope of R&U. The work will be taken up by M/s Alstom

shortly.

KPTCL

Annexure-II

Page 9 of 26

220kV Sedam-

Tandur line

Line tripped on Yphase to earth fault from

both the ends

20-12-2014

at 22:20 hrs

KPTCL was requested to explore the possibility of providing A/R

feature to this line and submit the remedial measures to the PCSC

forum.

KPTCL

Mail received on 27-05-2015 & 29-07-2015:

1. C&R panels of 500MVA ICT 1&2 will be replaced under scheduled

R&M works.

2. O&M personnel are instructed to take sufficient care in order to avoid

unwarrented trippings. --- Completed.

KPTCL mail received on 23-01-2016:

New C&R panels(with numerical relays) erected for 500MVA ICT-1 &2

under R&M work, which will be commissioned shortly.


New C&R panels(with numerical relays) erected for 500MVA ICT-1 &2

under R&M work, which will be commissioned shortly.

KPTCL1. PCSC forum recommended KPTCL to replace the relay with a

different make.

2. KPTCL was also requested to train the O&M personnel adequately

before performing any maintenance works to avoid such unwanted

trippings.

Suspected mal-operation of 220kV side

Rphase

over current relay

01-12-2014Tripping of 400/220kV

ICT-2 at Hoody

substation of KPTCL

39/I/5

GD-1 at 220kV Ambewadi

Station of KPTCL

40/I/1

40/IV/1

Triggering 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.

22-12-2014

at 21:22 hrs

Pending

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.

Pending

PendingMail recieved on 29-07-2015:

Carrier protection is being restored for 220kV Sedam-Tandoor line at

Sedam end. After restoring the carrier protection , AR will be enabled.

KPTCL mail recieved on 23-01-2016:

Carrier protection is being restored for 220kV Sedam-Tandoor line at

Sedam end. After restoring the carrier protection , AR will be enabled.


SEE,SCADA to update the latest status


Action is being taken to restore carrier protection.AR will be enabled once

carrier signal is restored.

KPTCL Mail received on 28-04-2015:

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.

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


1. Action is being taken by KPTCL for operating Ambewadi in split bus

mode. Problem in bus coupler breaker is attended.Isolator overhaulling

work is completed.PTs are already provided to 220kV Bus-II. After

commissioning of Bus-II PTs, Ambewadi can be operated in split bus

mode. Pending works will be completed within a months time.


Bus-II PTs yet to be commissioned.Planned to complete before end of

April-2016.

Annexure-II

Page 10 of 26

Fault occurred in 220kV Sedam-Shahpur

line

Fault in 220kV Ambewadi-Nagjheri line-2

KPTCL

KPTCL to activate non-directional Over Current protection with a time

delay of 600-800 msec for Fuse

failure condition at Lingasugur.


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.

Tripping of Unit-1&2

along with 400/220kV

ICT-2 at Raichur TPS

KPTCL

27-01-2015

at 8.00 hrs

42/I/2

(GD)

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.

41/I/4 Complete outage at 220kV

Sedam Substation of

KPTCL (GD-1)


Sedam substation of

KPTCL

42/I/1

(GD)

47/II/13

15-02-2015

at 14:24 hrs


Ambewadi substation of

KPTCL

220kV RTPS-Lingasugur line-2 tripped at

TPS end on operation of distance

protection zone-1. 400/220kV ICT-2 got

tripped on operation of earth fault

protection. 220kV RTPS-Lingasugur line-

1&3 tripped on distance protection zone-2

and zone-3 respectively. Due to tripping of

ICT-2, the running units got overloaded and

it was mentioned that under frequency

occurred as units are on load control. The

Units got tripped on under frequency.

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.

1. KPTCL shall provide A/R feature on Ambewadi – Ponda 220 kV

D/C inter-state line.

2. 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.

06-08-2015

at 4:51 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.


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


Tandoor line. AR will be enabled.



stage.




1. Bus bar protection panels pocured and erected at Sedam. Wiring ,

testing ,commissioning is being taken up.Planned to complete by April

2016.



12-03-2015

at 7:51 hrs

KPTCL

PendingMail received on 27-05-2015:

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

2. A/R yet to be enabled.



stage.



KPTCL

Pending

Pending

PendingYet to be informed

Annexure-II

Page 11 of 26


Ambewadi-Ponda line-2

02-08-2015

at 13:20 hrs

Line tripped on a transient fault in B-phase.

There is no

provision for auto reclose.



08-08-2015

at 10:51

hrs and 09-

08-2015 at

Line tripped on a B-phase to earth fault.

Line tripped as there is no provision for auto-

reclose



17-08-2015

at 13:20 hrs

Line tripped on a transient fault . There is no

provision for Auto reclose.

Yet to be informed

KPTCL to fast-track providing A/R on all 220 kV lines emanating

from Ambewadi SS to prevent Station shut-down on temporary faults.

48/I/3

(GD)

Failure of Lightning Arrestor of Y-phase

Line Reactor of 400kV Guttur-Hiriyur line-1

and line tripped on distance protection Zone-

1. Bus-bar protection of 400kV Bus-2 at

Guttur substation also got operated during

the event sensing this through fault. 400/220

kV ICT-1 & 2 at Guttur, 400kV Kaiga-

Guttur-2, 400kV

Guttur-Narendra-2, 400kV Guttur-Hiriyur-2

and 400kV Guttur-Munirabad which are on

400kV Bus-2 got tripped during the

incident. 400kV Guttur-Narendra-1 which

was on Bus-1 also tripped at the same time.

51/II/21 Multiple tripping at 400kV

Guttur sub-station

17-01-2016

at 18:53 hrs

48/I/2

(GD)


Peenya Substation in

Karnataka

49/I/1.3

(GD)


Ambewadi Substation of

KPTCL

Till A/R is put into service on Ambewadi-Ponda line-1, KPTCL to

reduce Zone-2 time setting to zero sec. at Ambewadi end.

Outage of 220kV

Ambewadi station in

Karnataka


Will be complied in a months time.

Pending

PendingKPTCL Mail received dated 25-05-2016:

SEE, RTC, Bangalore to update the status

KPTCL Mail received dated 28-06-2016:

Providing numerical bus bar protection to 400kV buses and GPS time

synchronising equipment at Guttur is considered under R&U. Work is

awarded to M/s Alstom, execution will be taken up shortly

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.

KPTCL

KPTCL

1. KPTCL to configure all DR’s and EL’s at 400 kV Guttur SS so that

they will also get triggered for BBP operation.

2. KPTCL to ensure time-synchronization of all DR’s and EL’s with

GPS at their 400 kV Guttur SS.

220kV 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

27-09-2015

at 4:23:17

hrs

All connected 220kV lines and transformers

were taken on 220kV North bus as South

bus was under shut down for conversion of

strung bus to rigid bus and isolator

replacement under R&M works. Failure of

HV side Y phase CT of 150MVA

Transformer-3 occurred at Peenya

Substation which resulted in operation of

Differential and HV REF protection. The

KPTCL to revise distance relay settings at Nelamangala end for 220

kV Nelamangala – Hebbal - Peenya line – 1 for the effective line length

of 17 km. These new settings can be appropriately reviewed as and

when the tie-arrangement at Hebbal is done away with.

KPTCL

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

KPTCL

Pending

KPTCL


Presentl 220kV Nelamangala -Hoody(i.e. nelamangala-Peenya-Hebbal -

Hoody line is made LIILO at Yelahanka sub station and breaker at

Peenya is kept open, necessary modification in distance relay settings

adopted for new configuration.

Yet to be informed

29.10.2015

at 14:34 hrs

Pending

Pending

Annexure-II

Page 12 of 26

52/I/3

(GD)


Shimoga substation

22-02-2016

at 15:03 hrs

220kV Bus Bar protection operated during

failure of R phase CT in DVG-2 line bay.

KPTCL to operate 220 kV Shimoga on multi-bus operation under

normal conditions, put it on single-bus operation only under emergency

conditions.

KPTCL Yet to be informed Pending

55/II/4 Tripping of 400/220kV ICT-

1 & 2 at Hoody substation

27-05-2015

at 08:08 hrs

Triggering incident was failure of newly

erected R and Y phase sectionalizer CT of

220kV North bus at 220kV Hoody SS.

KPTCL to furnish Equipment Failure Report (EFR) CEA with a copy

marked to SRPC.


56/I/1 Complete outage of

400/220kV Hoody

substation of KPTCL.

02-06-2016

at 4:56 hrs

Bushing of R-phase ICT -2 got failed at

Hoody station at 3:09 hrs. ICT-1&3 and

400kV lines at Hoody substation were hand

KPTCL to furnish Equipment Failure Report (EFR) CEA with a copy

marked to SRPC.



Ambewadi-Ponda (Xeldam)

line-1

10-06-2016

at 13:33 hrs

Line tripped on Y-E faut due to DPR, Z1

operation

KPTCL to keep A/R for Ambewadi – Ponda (Xeldam) line-1 in service

with immediate effect.


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.

51/I/3

Failure of Lightning Arrestor of Y-phase

Line Reactor of 400kV Guttur-Hiriyur line-1

and line tripped on distance protection Zone-

1. Bus-bar protection of 400kV Bus-2 at

Guttur substation also got operated during

the event sensing this through fault. 400/220

kV ICT-1 & 2 at Guttur, 400kV Kaiga-

Guttur-2, 400kV

Guttur-Narendra-2, 400kV Guttur-Hiriyur-2

and 400kV Guttur-Munirabad which are on

400kV Bus-2 got tripped during the

incident. 400kV Guttur-Narendra-1 which

was on Bus-1 also tripped at the same time.

51/II/21 Multiple tripping at 400kV

Guttur sub-station

17-01-2016

at 18:53 hrs

220kV Peenya-Nelamangala-3 tripped on B-

E fault at both ends. At the same time,

220kV Peenya-Nelamangala-4 tripped on R-

Y fault only at Nelamangala end, and was in

service from Peenya end. Due to tripping of

these two lines, 220kV Peenya-Nelamangala-

2 tripped on overcurrent protection.


Peenya Substation of

KPTCL

KPTCL to furnish a report on the tripping of 220 kV Peenya-

Nelamangala line-4 Nelamangala detailing the remedial measures taken

including the settings adopted for Z1B (Zone extension) and Power

Swing Block.




Providing numerical bus bar protection to 400kV buses and GPS time

synchronising equipment at Guttur is considered under R&U. Work is

awarded to M/s Alstom, execution will be taken up shortly

KPTCL

1. KPTCL to configure all DR’s and EL’s at 400 kV Guttur SS so that

they will also get triggered for BBP operation.

2. KPTCL to ensure time-synchronization of all DR’s and EL’s with

GPS at their 400 kV Guttur SS.

01-07-2016

at 03:03 hrs

Tripping of 220 kV

Chikkodi-Mudshingi and

220 kV Chikkodi-

Talandage lines

57/II/1

KPCL/ KPTCL



KPTCL

1.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.

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.


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.


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 at the earliest. ------ Pending

3. KPCL informed that Nagjhari- Kodasalli Lines 1 & 2 had been kept in

service since 23.05.2016 @ 08.06hrs. ---- Completed


Modifications to be carried in Nagzari SPS logic is submitted to

SRLDC/SRPC for verification and approval

16-03-2016

at 11:39 Hrs

22-02-2016

at 12:36 hrs

PendingComplete outage of 220kV

Nagjheri power station and

220kV Ambewadi

substation of KPTCL

Annexure-II

Page 13 of 26


Ambewadi Substation of

KPTCL.

24-06-2016

at 20:57hrs

B phase to earth fault had occurred in 220

kV Ambewadi-Ponda line-2. Fault was

cleared by tripping of feeders from remote

end

1.KPCL & KPTCL to furnish an action taken report on the

recommendations given by PSAG-16 to PCSC forum.

2.KPTCL to keep A/R for Ambewadi – Ponda line-2 in non-auto mode

(i.e., only 3-ph trip should get extended on occurrence of a fault) till the

line is closed from Ponda end.

KPCL/KPTCL Yet to be informed Pending

43/II/5 29-03-2015

at

15:29 hrs

Tripping of 400kV

Alamathy-

SVChatram line-1&2

and 400/230kV ICT

at S.V.Chatram




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.




KPCL/ KPTCLComplete outage of 220kV

Ambewadi station of

KPTCL and 220kV

Nagjheri of KPCL

18-03-2016

at 14:40 hrs

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.

51/I/3

Ambewadi 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

53/I/3

(GD)

Tripping of ICT-3 at

Raichur Substation

15-03-2016

at 12:28 hrs

ICT-3 tripped due to operation of back-up

earth fault protection during fault in 220kV

RTPS-Raichur line-1.


SEE,SCADA to update the status of healthiness of carrier protection of

220kV RTPS-Raichur 1 &2 lines


Details sought from KPCL for review of ICT's back up (high set)

proection settings as suggested. KPCL is yet to furnish the details

required to give the revised settings.

PendingKPCL/ KPTCL to check the ICT’s back-up (high-set) protection

settings, and ensure that they operate with a time delay of 100 msec.

TANTRANSCOTANTRANSCO was requested to swap the relays between two

stations, so that

Main-1 and Main-2 will be of different make at each station.

KPCL/ KPTCL

53/II/1

Tamil Nadu

KPCL/KPTCL

TANTRANSCO vide their mail dated 24.06.15 informed that different

relays in Main-I & Main-II would be ensured at the earliest.

Mail recieved on 24-07-2015 ,19-02-2016 and 24-03-2016:

Different relays in Main-I & Main-II will be ensured.


TANTRANSCO: Not feasible in the existing SAS sub stations. Hence,

exemption may be given for these sub stations.

Mail received on 20-05-2016 ,16-06-2016,25-07-2016 & 24-09-2016 :

As discussed in the 52nd PCSC meeting, Swapping of Relays between

two stations is not feasible in the existing SAS sub stations. Hence,

exemption may be given for these sub stations.

Pending

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.




Line-2 tripped on R-phase to earth fault.

Line autoreclosed at SVChatram end and

failed to reclose at Alamathy end. Bphase to

earth fault in line-1. Line tried for A/r but

due to permanent fault line did not reclose.

ICT tripped on operation of over flux

protection.


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 at the earliest. ------ Pending

3. KPCL informed that Nagjhari- Kodasalli Lines 1 & 2 had been kept in

service since 23.05.2016 @ 08.06hrs. ---- Completed




22-02-2016

at 12:36 hrs

PendingComplete outage of 220kV

Nagjheri power station and

220kV Ambewadi

substation of KPTCL

Pending

Annexure-II

Page 14 of 26

48/I/1

(GD)

Complete outage of 230kV Palladam, 230

kV Othakalmandapam S/s, 230 kV

Coimbatore S/s, 230 kV Thudialur and 230

kV Sadayapalayam S/s

Pending TANTRANSCO to take suitable measures like installing more stub-

towers along 230 kV OK Mandapam – Myvady line to avoid excessive

sag due to over-loading.

TANTRANSCO05-09-2015

at 14:04 hrs

TANTRANSCO Mail received on 19-02-2016, 24-03-2016 and 27-04-

2016:

230kV Othakalmandapam - Myvadi feeder will be made LILO at Kongal

Nagar. Line restringing will be carried out along with the above proposal.

Mail Received on 20-05-2016 ,16-06-2016,25-07-2016 & 24-09-2016:

230kV Othakalmandapam - Myvadi feeder will be made LILO at Kongal

Nagar. Line restringing will be carried out along with the above proposal.

Disturbance in 220kV

Tamilnadu system

Annexure-II

Page 15 of 26

1. 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.


Madurai S/s (Chekanaurani)

of TANTRANSCO

51/I/1

(GD)

19-01-2016

at 11:56 hrs

TANTRANSCO to take steps to provide double-bus operation at their

230 kV Gummidipoondi SS.

TANTRANSCO 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.


Mywadi station of

TANTRANSCO

50/I/3

(GD)

TANTRANSCO mail received on 24-03-2016 :

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.

Mail recieved on 27-04-2016 and 20-05-2016 ,16-06-2016, 25-07-2016

& 24-09-2016:

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.

Pending

TANTRANSCO Mail received on 19-02-2016, 24-03-2016 and 27-04-

2016:

LBB scheme will be tested while availing Line Clear.

Mail Received on 20-05-2016 ,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.

Pending

Complete outage of 230 kV Gummidipoondi Station of

TANTRANSCO

12-05-2016 at 12:15 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

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

Busbar protection got operated for a fault in

230kV Mywadi-Anaikadavu line

Pending

50/II/17 TANTRANSCO to check the LBB scheme for LV side CB of ICT-3,

and furnish the remedial measures taken to PCSC forum.

21-12-2015

at 6:28 hrs

400/230kV Myvadi ICT-3 tripped due to the

operation of 230 kV CB LBB protection at

230 KV bus (TNEB) of Myvadi station.

27-11-2015

at 17:26 hrs

Tripping of 400/230kV

Myvadi ICT-3

55/I/1

(GD)

TANTRANSCO

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.

TANTRANSCO Pending

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.

Annexure-II

Page 16 of 26


Sriperambudur -

SV.Chartam and 400kV

Nellore-Sriperambudur line-

1

05-04-2016

at 00:11 hrs

400kV Nellore-Sriperambudur line-1 tripped

on a R-phase to earth fault. 400kV

Sriperambudur-S.V.Chatram line tripped at

Sriperambudur end only on operation of

over current protection

PGCIL (SR-II) to check and revise Pole Discrepancy Relay (PDR) time

setting appropriately based on the type of A/R scheme being

implemented at their 400 kV Sriperambudur SS.

PGCIL (SR-II) Yet to be informed Pending

54/III/3 Tripping of 400 kV

Kalvindapattu-Vallur line

10-04-2016

at 14:59 hrs

R-phase to earth fault had occurred in line.

Auto reclose attempt is unsuccessful/ auto-

reclose could not be established from

provided DR/ EL.

PGCIL (SR-II) to furnish a report on the tripping event detailing the

reasons for unsuccessful A/R operation at Kalvindapattu end, and the

remedial action taken to restore A/R to normalcy.


1.PGCIL (SR-I) to properly configure EL’s at Hyderabad station with

time-scale resolution up to msec; further, DR’s should also be

configured for showing both Analog and Digital data with properly

defined X-axis and Y-axis scales.

2.PGCIL (SR-I) to follow the FILE Naming Nomenclature provided by

SRPC in naming various tripping files (FIR/DR/EL/TR) being uploaded

in SRLDC’s Tripping Monitor System (TMS) portal.


protection at Hyderabad end and Direct Trip

was received at N’sagar. Over-voltage, Stg-

2 operation was observed in EL of

Hyderabad station.

08-05-2016at

4:57 hrs

Tripping of 400kV

Hyderabad - N’sagar line

Pending

(Recommendat

ion No.1)

220 kV breaker of unit-3 at Idukki Power

house flashed and bus differential protection

acted. All Generators (6Nos.) along with all

220 kV feeders tripped during the incident.


1. Reducing the sensitivity of REF protection of Unit # 4, 5, 6 at Idukki

PH: - Generation wing is planning to purchase new transformer

management relays with low impedance REF protection. Purchase

procedures initiated. ---------Pending

2. The replacement/ repair of faulty breakers are under the consideration

of Generation wing. Breakers will be replaced / repaired in a phased

manner. Unit #3 breaker was replaced with available breaker from the

220kV IDMD feeder. The 220kV CBs of unit #2 and unit #3 will be

replaced with in two months.

3. No abnormalities were noticed in the PLCC equipment at New Pallom

station. It is kept under observation.


1. Purchase procedures is still in progress.

2. Replaced.

3. PLCC equipment Tested and found OK.


1. Even though repeated plans to have a joint inspection with M/s.ABB

who is the OEM of the relay panel for replacing the relays with numerical

ones, the same could not become successful. Finally, the inspection has

been fixed on 15.03.2016. It has been planned to replace existing REF

protection with low impedance ones after retrofitting the numerical ones

of OEM.


1.Generation wing is planning ti provide low impedance REF protection

by retrofitting numerical ABB make transformer management relay in the

existing panel. ---- Pending.

2.Faulty breaker of Unit3 has been replaced. ---- Completed.

3.PLCC equipments in the feeder were checked and found OK. ------

Completed.

KSEB

Pending

Kerala

PGCIL (SR-I & SR-II)

1. KSEB to reduce sensitivity of REF protection appropriately at Idukki

PH.

2. KSEB to replace/ repair the faulty breaker.

3. KSEB to check the PLCC equipment at New Pallam and inform the

remedial measures taken to PCSC forum.

Complete outage of Idukki

Hydro Power Station (GD-

1)

44/I/1

(GD)

28-04-2015

at 12:30 Hrs

55/II/5 PGCIL (SR-I) Yet to be informed

Annexure-II

Page 17 of 26

1.PGCIL (SR-I) to properly configure EL’s at Hyderabad station with

time-scale resolution up to msec; further, DR’s should also be

configured for showing both Analog and Digital data with properly

defined X-axis and Y-axis scales.

2.PGCIL (SR-I) to follow the FILE Naming Nomenclature provided by

SRPC in naming various tripping files (FIR/DR/EL/TR) being uploaded

in SRLDC’s Tripping Monitor System (TMS) portal.


protection at Hyderabad end and Direct Trip

was received at N’sagar. Over-voltage, Stg-

2 operation was observed in EL of

Hyderabad station.

08-05-2016at

4:57 hrs

Tripping of 400kV

Hyderabad - N’sagar line

Pending55/II/5 PGCIL (SR-I) Yet to be informed

Annexure-II

Page 18 of 26

55/II/9 Tripping of HVDC

Gazuwaka pole-2

19-05-2016

at 11:41 hrs

Pole tripped on operation of differential

current protection of east side of Pole-2

PGCIL (SR-I) to take up the issue of differential protection operation of

converter transformer on low voltage fluctuations with their OEM, and

submit a detailed report on it.

PGCIL (SR-I) Yet to be informed Pending

56/II/11 Tripping of HVDC

GazuwakaPole-2

19-06-2016

at 5:20 Hrs

HVDC Pole-2 got tripped on operation of

Bus differential protection

PGCIL (SR-I) to get the tripping of HVDC Pole-2 tripping on Win-Bus

differential protection thoroughly investigated for correctness of

operation, and submit a report thereon.


56/III/7 Tripping of 400 kV

Khammam-N’sagar line-1

05-06-2016

at 22:41 hrs

Line tripped on B-phase to earth fault. Line

auto-reclosed successfully at N’sagar and

failed to auto-reclose at Khammam

1.PGCIL (SR-I) to configure DR & EL at N’sagar (Tallapalli) end so

that full operation of A/R is captured.

2.PGCIL (SR-I) to investigate the reasons for non-operation of A/R of

Tie-CB at N’Sagar end, and resolve them suitably.


55/II/7 Tripping of 400kV Kudgi

PG (Narendra New) -

Narendra-PG line-2

18-05-2016

at 16:25 hrs

line tripped on B-phase to earth fault and

line auto-reclosed successfully from

Narendra end. Line tripped from Kudgi-PG

due to operation of over-voltage stage-1

PGCIL (SR-II) to properly configure dead-time of A/R (typically 1 sec)

on all lines emanating from Narendra (PG) substation.


55/II/17 Tripping of HVDC Talcher-

Kolar pole-1

30-05-2016

at 09:49 Hrs.

Failure of main CT of AC filter (20C08A)

occurred and it in turn caused the operation

of filter bank differential protection. HVDC

Pole-1 got tripped on group Differential

protection operation

PGCIL (SR-II) to take up the issue of Pole-1 tripping on Group

Differential Protection (Stage-II) due to multiple commutation failures

with their OEM, and furnish a report on it.


56/II/8 Tripping of HVDC Talcher-

Kolar Pole-1

17-06-2016

at 16:35 Hrs

Talcher-Kolar HVDC Pole-1 got tripped on

line fault and Pole-2 went to ground return

mode with 150MW

PGCIL (SR-II) to address & resolve DTPC and fibre-optic link related

issues raised by KSEB at Thrissur/ Madakathara substations, and

conduct a mock-test in coordination with KSEB to verify integrity of

signal transmission from Kolar to Thrissur/ Makadathara.


Others

Tripping of 400kV

Alamathy-Tiruvalam line-1

and 400kV Alamathy-

Vallur line-2

57/II/2 Tripping of 400 kV Mywady-Salem line-1 and 400 kV Mywady-Madurai line

51/II/4 400kV Vallur-Alamathy Line-2 got tripped

from Vallur end during failure of Y-phase

LA in 400kV Alamathy-Tiruvalam line.

Protection at Vallur end tried for an auto-

reclose and gave a 3 phase trip.

13-12-2015

at 22:42 hrs

TANTRANSCO mail received on 24-03-2016:

3Ф Trip at 400kV Alamathy end due to DT received from vallur end for

BФ LAS bursted in Alamathy -Thiruvalam - 1 # at Alamathy end.

Mail received on 27-04-2016 and 20-05-2016:

3Ф Trip at 400kV Alamathy end due to DT received from vallur end for

BФ LAS bursted in Alamathy -Thiruvalam - Line-1 at Alamathy end.

PendingNTECLNTECL, Vallur to furnish a report detailing the reasons for mal-

operation of Vallur end relays for a fault on Alamathy-Tiruvalam line-1,

and remedial measures taken to PCSC forum. In the report, their

preparedness for implementing line differential protection on Vallur-

Alamathy lines may also be indicated.

03-07-2016 at 03:06 hrs

400kV Mywady- Madurai line tripped on a Y-phase to earth fault due to agriculture fire. Tie-CB LBB relay got operated at Mywady end and resulted in tripping of Main breakers of 400kV Mywady-Madurai and 400kV Mywady-Salem line-1 which are in the same diameter.

PGCIL (SR-II) to furnish a report on the remedial action taken after ascertaining the reasons for (i) non-opening of Main-CB of Mywady – Madurai line at Mywady end on Tie-CB LBB operation, and (ii) delay in sending DT to the remote ends after Tie-CB LBB operation.


Annexure-II

Page 19 of 26

56/III/5 Tripping of 400 kV Neyveli

TS-2-Pugalur line

04-06-2016

at 16:36 hrs

B phase to earth fault occurred in line. Auto-

reclose had not operated at NLC TS-2 and

DT was sent to Pugalur end resulting in a 3

phase trip

NLC to review the necessity of providing Relay Definitive Trip, and

accordingly take steps to disable it on all lines emanating from their

generating stations.

NLC Yet to be informed Pending

56/II/16 Tripping of 400 kV Gajwel-

Singareni line-2

30.06.2016

at 23:43 hrs

Tripped on 3-phase Trip at Gajwel end SCCL to configure Jaipur end relay’s EL properly so that the time-

stamp resolution is extended downwards up to milli-second level.

SCCL Yet to be informed Pending

57/II/8 Tripping of 400 kV

Ramagundam - Dichipally

line

16-07-2016

at 4:38 hrs

Line tripped at Ramagundam end on

operation of over-voltage protection.

Dichipally end tripped due to receipt of

Direct Trip signal.

1.NTPC-Ramagundam to ensure correctness of operation of Over

Voltage relays by taking remedial measures like maintaining

healthiness of concerned CVT’s, setting drop-off to pick-up ratio at

0.97 & above, etc.

2.NTPC-Ramagundam to ensure time sync of their station’s DR & EL

with GPS.

3.NTPC-Ramagundam to sort out analog values indication &

overlapping issue of time-stamp in their station DR’s.

4.NTPC-Ramagundam to properly configure their EL’s so that events

are recorded with msec. resolution.

NTPC (Ramagundam) Yet to be informed Pending

Tripping of 400 kV Gajwel-Singareni line-2

57/II/4

54/I/1 Complete outage of 230 kV

S.P.Koil Station of

TANTRANSCO

02-04-2016

at 17:08 hrs

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 for DR & EL

from Main-I & Main-II relays on all 230 kV lines emanating from

MAPS.

3.MAPS, in co-ordination with SP Koil, to carry out PLCC end-to-end

testing, on SP Koil – MAPS lines 1 & 2, and ensure healthiness of

PLCC communication & carrier-aided protection.

4.MAPS to put in service Auto-Reclosure feature on all four 230 kV

lines emanating from MAPS by June, 2016.

NPCIL (MAPS) Yet to be informed

Yet to be informed Pending

Pending

1.Singareni TPS to furnish single line diagram of their switchyard along with the Over Voltage Relay settings adopted for various transmission lines, and to ensure that they are in line with the SRPC provided gradings.2.Singareni TPS to upload various tripping files (FIR/DR/EL/TR) pertaining to a tripping event involving their station in SRLDC web-portal within 24-hrs of occurrence of that event in compliance of IEGC Regulation 5.2(r).

Line tripped on operation of Over-Voltage protection at Singareni and Direct Trip was received at Gajwel. DR & EL of Singareni was not furnished

SCCL10-07-2016 at 1:56 hrs

Annexure-II

Page 20 of 26

KPCL/

TSTRANSCO/

PGCIL (SR-I)

40/II/3 Tripping of 400

kV TALAGUPPA

– HASSAN line

01-01-2015

at

13:38 hrs

On account of R-phase to earth fault, line

tripped at Hassan end due to operation of

distance Zone-2 and non-receipt of carrier.

From D.R of Talaguppa end it is observed

that fault had occurred in Yphase.

1. PGCIL and KPTCL to ascertain the reason for the phase discrepancy

in the relay operation and take suitable remedial measures.

2. KPTCL to check the PLCC operation at Talaguppa end and submit

the report to the PCSC forum.

09-03-2015

at

06:36 hrs

Multiple tripping at Raichur

TPS of

KPCL

42/II/18

34/I/6 400/220 kV ICT-1 & 2 at

MUNIRABAD

400kV Raichur TPS-Raichur(PG) line-

1&2, 400kV Raichur-Mahboobnagar,

Unit#7 and ICT-2 at RTPS tripped

during the incident. B phase to earth

fault had occurred in 400kV Raichur

TPS-Raichur line-1

PGCIL (SR-II)/ KPTCL Mail recieved on 28-04-2015:

End to end testing of PLCC has been done and problem in the PLCC is

atttended.


End to end testing of PLCC has been done and problem in the PLCC is

atttended. Phase discrepancy in the relay operation is to be checked

jointly.

Mail recieved on 02-09-2015 from PGCIL (SR-II):

Problem is in identification of phases at Talguppa end. To be rectified by

M/s KPTCL.

Mail recieved on 28-06-2016 from KPTCL:

The matter is reffered to the concerned Operation and maintance wing to

set right the mismatch of phases in 400kV Talaguppa-Nelamangala and

Talaguppa-Shantigrma lines at Talaguppa in cordination with PGCIL .

Pending

(with KPTCL)

Miscellaneous

16-07-2014

1. Yet to be informed by KPCL. ---- Pending

2. Mail received on 26-05-2015 from TSTRANSCO:

It is found that the main-2 ABB make REL316 type distance relay was

defective and same was replaced with MICOM P444 by M/s.PGCIL on

23.04-2015. After replacement of main-II, DR can be extracted from this

relay. For EL in to service, some field winding is pending which is being

taken up in this month. -- Complied with

3.

PGCIL mail recieved on 27-04-2016:

End to end PLCC tunning carried out.

PGCIL (SR-I) RVMD 14.07.2016:

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

Ramakrishna Commettee recomendations and implemented. - Complied

with.

1. KPCL to review REF setting (DMT or IDMTL) for unit-7 by first

week of April, 2015 and inform the same to PCSC forum.

2. TSTRANSCO to furnish Mehaboobnagar’s DR and EL and the

reasons for distance relay operation at their end within a week’s time.

3. PGCIL (SR-I) to rectify the issues relating to A/R operation, relay

reach (Z2), reverse reach (Z4) and SOTF auxiliary contacts within a

week’s time, and submit the actions taken to PCSC forum.

Mail recieved on 27-05-2015 (KPTCL):

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

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

Mail received on 29-07-2015 (KPTCL):

Initial Tendering stage


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

Zone, Gulbarga will take up necessary procurement and further execution.

----------------------------------------------------------------------

1. Pending from KPTCL side.

2. Complied with as per PGCIL (SR-I) RVMD 14.07.2016, which stated

that "Relay settings of all the stations in SRTS-1 were derived as per

Ramakrishna Commettee recomendations and implemented."

3. Pending from KPTCL side.

KPTCL/

PGCIL (SR-I)

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.

As reported directional over current relay of

ICT’s operated due to snapping of line

jumper in 220kV Lingapur line.

Pending (with

KPCL)

Pending

(with KPTCL)

Annexure-II

Page 21 of 26

Tripping of Unit 1 at

NCTPS

24-05-2015

at 19:13 hrs

ID Fan trip

Tripping of Unit 1 at MEPL 24-05-2015

at 19:13 hrs

Coal Mill tripped

Tripping of Unit 1 at

Krishnapatnam

24-05-2015

at 19:17 hrs

Generator Protection operated

Tripping of Unit-8 at RTPS 24-05-2015

at 19:19 hrs

Tripped on Overvoltage.

TANGEDCO vide their mail dated 07.07.2015 informed that as per the

discussion and recommendation of 44th meeting of PCSC held on

28.05.2015, a time delay of 2 Sec had been introduced for the above

tripping for all the ID fans at NCTPS-II.

MEPL vide their mail dated 14.09.2015 informed that they had

implemented 2 seconds delay for under voltage tripping of all Drag Chain

Feeder Conveyors. And this has been done for both the Units.

APGENCO letter dated 18.03.2016:

The unit not tripped on Generator protection but tripped on Economiser

inlet flow protection consequent to tripping of TDBFP on lube oil

pressure low.Before tripping , dip in voltage was observed in the LT

system which caused tripping od lube oil pumps.After the

incident,Changeover scheme on under voltage of LT System was reduced

from 80% with 2 sec delay to 40% with 200msec delay

Pending (with

KPCL,

APGENCO)


1.SOE and SLD are attached. The DR of 405 CB is not generated during

the incident. Now the problem is identified and rectified.

--------- Completed

2.All the 3 lines i.e CHTR-2, MNBL-I & II tripped in zone

protection. The fault was in Blind zone i.e P2 side of CT, where it was

covered under Bus fault by the time fault moved on to P1 side when the

fault comes under STUB/TEED zone after 330msec all the feeders expect

CHTR-1 tripped in Zone-II and total fault persisted for 500msec before

the 405 TIE CB opens and clear the fault. As a remedial the STUB

protection operation also checked and found OK.-------Completed

3.The Time Sync was missed on the day and found there was problem

with LAN Timer same was rectified. Now found OK.

-----------Completed

4.Now the DR Time scale changed to 1 sec for Pre fault and 3 sec for Post

fault and STATE of events are corrected wherever found wrong/or

misguiding during analysis.---------Completed.

5.

PGCIL-SR1 RVMD 27-04-2016:

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

400kV RCR-RTPS-D/C is under tendering.


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 under technical evaluation

Pending with

PGCIL(SR-I)

44/I/3 1. All Tripped units, viz., Krishnapatinam, MEPL, Raichur, NCTPS to

submit a detailed report on this event including the remedial measures

taken to PCSC forum.

2. KPCL to check the excitation system of Unit 8 of RTPS, and submit

the remedial measures taken to PCSC forum.

KPCL/ MEPL/

APGENCO/ TNEB


Krishnapatnam TPS

08-09-2015

at 18:20 hrs

As per FIR submitted, CT damage observed

in Chitoor-Main bay (404). Main breakers

connected to bus-1 (401, 404, 407, 410) got

tripped on operation of bus bar protection.

Unit-1 tripped on operation of MFT. Unit-2

was not in service

1. APGENCO to furnish to PCSC forum (i) A3-size Single Line

Diagram of SDSTPS, and (ii) the sequence of events with time stamp

showing the protection that opened Tie-CB (405) at SDSTPS.

2. APGENCO to review STUB/TEED protection in all dias at SDSTPS

and ensure that they are configured for instantaneous operation.

3. APGENCO to properly configure the STATE of the tripping events

so that they get recorded appropriately like TRIP/ OPERATED in their

corresponding Event Loggers.

4. APGENCO to ensure time sync of all DR’s and EL’s at SDSTPS.

5. PGCIL (SR-I) to provide line differential protection for 400 kV NPS

–Nellore-PG lines 1 & 2.

APGENCO/ PGCIL (SR-

I)

Annexure-II

Page 22 of 26

50/II/11 Tripping of 400kV Neyveli

TS2-Pugalur line

14-11-2015

at 4:01 hrs

Line tripped on operation of over voltage

protection at Pugalur end. However from

DR it was observed that the voltages were

below the O/v stg-1 threshold limits

1. NLC to configure DT receipt event from Pugalur for triggering DR

and EL at NLC TPS II.

2. PGCIL (SR-II) to check drop-off to pick-up ratio of OVR relay at

Pugalur and configure its operation as per SRPC provided OVR

gradings.

PGCIL (SR-II)/

NLC

NLC mail received on 25-03-2016 and 27-04-2016:

Recommended configuration of DR/EL will be done during shut down of

feeder

NLC mail dated on 25-06-2016:

Scheduled to take up the activity on 30.06.2016

Pending

1. For Gooty –Nelamangala line, PGCIL (SR-I) and KPTCL to provide

3-ph trip logic at their respective ends upon detection of PLCC link

failure during dead-time of A/R operation.

2. PGCIL (SR-I) to make GPS functional at Gooty SS, and ensure time-

sync of various DR’s and EL’s with it (GPS).

3. PGCIL (SR-I) /KPTCL to furnish reason for the operation of Backup

impedance protection of the line reactor at Nelamangala end and the

remedial measures taken to PCSC forum.

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. rel;ay for all short lines emanating

from NPS is being taken up with our corporate. -------- Pending.





PendingPGCIL (SR-I),

MEPL, SEL, TPCIL,

NCC

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 – NCCK 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.

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)-

ECC line

30-12-2015

at 06:02hrs

47/II/7

50/II/8 Tripping of 400kV Gooty-

Nelamangala line

Mail recieved on 25-05-2016 from KPTCL:

Availability of week end infeed with eco feature to be confirmed by

SEE,RTC,Hubli

Pending1. KPTCL/ KPCL to see the possibility of implementing Weak Infeed

logic with Echo feature enabled by Under

Voltage (27) element on Kadra-Karwar lines 1 &2, and implement the

same if feasible.

2. NPCIL to time-coordinate Kaiga’s DEFR settings with (i) Zone-2

settings at Kaiga, and (ii) primary protections of the lines emanating

from Kadra and Kodasalli.

3. KPCL to ensure time-sync of EL’s, and healthiness of the Fault

Locators at Kadra.


1.SOE and SLD are attached. The DR of 405 CB is not generated during

the incident. Now the problem is identified and rectified.

--------- Completed

2.All the 3 lines i.e CHTR-2, MNBL-I & II tripped in zone

protection. The fault was in Blind zone i.e P2 side of CT, where it was

covered under Bus fault by the time fault moved on to P1 side when the

fault comes under STUB/TEED zone after 330msec all the feeders expect

CHTR-1 tripped in Zone-II and total fault persisted for 500msec before

the 405 TIE CB opens and clear the fault. As a remedial the STUB

protection operation also checked and found OK.-------Completed

3.The Time Sync was missed on the day and found there was problem

with LAN Timer same was rectified. Now found OK.

-----------Completed

4.Now the DR Time scale changed to 1 sec for Pre fault and 3 sec for Post

fault and STATE of events are corrected wherever found wrong/or

misguiding during analysis.---------Completed.

5.


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

400kV RCR-RTPS-D/C is under tendering.





Pending with

PGCIL(SR-I)

Complete outage of TPCIL

power station

50/I/2

220kV Kadra-Karwar lines-1&2 tripped

on earth fault in B-phase in zone-2.

Kaiga-Kadra line tripped at Kaiga end

only on operation of directional eath

fault protection.

R-phase to earth fault had occurred in Line.

Line did not auto-reclose from both ends. It

was mentioned that Y&B pole breakers at

Neelamangala tripped on operation of pole

discrepancy and backup impedence

protection for line reactor got operated.

12-11-2015

at 00:20 hrs

31-07-2015

at

11:44 hrs

Tripping of 220kV Kadra-

Karwar lines - 1&2 and

220kV Kaiga-Kadra line

KPTCL/ KPCL/ NPCIL

(KAPS)


Krishnapatnam TPS

08-09-2015

at 18:20 hrs

As per FIR submitted, CT damage observed

in Chitoor-Main bay (404). Main breakers

connected to bus-1 (401, 404, 407, 410) got

tripped on operation of bus bar protection.

Unit-1 tripped on operation of MFT. Unit-2

was not in service

1. APGENCO to furnish to PCSC forum (i) A3-size Single Line

Diagram of SDSTPS, and (ii) the sequence of events with time stamp

showing the protection that opened Tie-CB (405) at SDSTPS.

2. APGENCO to review STUB/TEED protection in all dias at SDSTPS

and ensure that they are configured for instantaneous operation.

3. APGENCO to properly configure the STATE of the tripping events

so that they get recorded appropriately like TRIP/ OPERATED in their

corresponding Event Loggers.

4. APGENCO to ensure time sync of all DR’s and EL’s at SDSTPS.

5. PGCIL (SR-I) to provide line differential protection for 400 kV NPS

–Nellore-PG lines 1 & 2.

APGENCO/ PGCIL (SR-

I)

PGCIL (SR-I) / KPTCL 1.

PGCIL RVMD 27.04.2016:

A/R blocked due to failure of PLCC link. The defective PLCCcards

replaced at Neelamgala end.


A/R blocked due to failure of PLCC link. The defective PLCCcards

replaced at Neelamgala end. End to end testing of PLCC carried out and

PLCC link is healthy. ------ Pending

2. Gooty end Time syc unit is replaced with new one and commissioned. --

------ Completed.

3. Yet to be informed by KPTCL. --- Pending

Pending

Annexure-II

Page 23 of 26


NTPL station and CEPL

Stations

14-03-2016

at 01:36 hrs

Running Units at NTPL and Coastal

Energen power station got tripped due to

tripping of evacuating lines.

NTPL and PGCIL (SR-II) to furnish compliance report of the

recommendations given by PSAG-15 Committee that held its meeting

on 12-13 April, 2016 at NTPL, Tuticorin.

PGCIL (SR-II)/

NTPL

NTPL mail received on 19.05.2016:

All General Recommendations will be done in the second week of June

2016 ---------- Complied by NTPL.

Yet to be informed by PGCIL (SR-II)

Pending

[with PGCIL

(SR-II)]

Pending

400kV Hoody-Nelamangala line-1&2,

400kV Hoody-Kolar line-1&2, 400/220kV

ICT-2 at Hoody tripped during the incident.

ICT-1&3 were hand tripped after the

incident.

PGCIL mail received on 27-04-2016:

Being pursued with APTRANSCO


AS maintenance being carrired out by PGCIL(SR-1), the required relay

replacement (wiring/programming) may also be carried out by PGCIL(SR-

1).


1. The CB problem has been attended by POWERGRID by using OEM

M/s BHEL services & POWERGRID's O&M spares.

------ Completed.

2. Being pursued with APTRANSCO to replace the faulty Event Logger

at Vijayawada (Nunna) SS. -------- Pending


As maintenance being carrired out by PGCIL(SR-1), the required relay

replacement (wiring/programming) may also be carried out by PGCIL(SR-

1).

PGCIL (SR-I)/

APTRANSCO

1. PGCIL (SR-I), in co-ordination with APTRANSCO, to address the

problem with CB at the earliest opportune time.

2. APTRANSCO to take steps to replace the faulty Event Logger at

Vijayawada (Nunna) SS.

Line tripped due to operation of over voltage

protection at Vijayawada end and Direct

Trip was received at Sattenapalli end

25-12-2015

at 3:01 hrs

Tripping of 400kV

Sattenapalli-Vijayawada

line

51/II/6 Pending

1. KPTCL to configure the Auto-Reclosure (A/R) scheme at Hoody

end for all lines emanating from Hoody end in such a way that in the

event of occurrence of faults during A/R dead-time, (i) it should

immediately give a 3-ph trip, and (ii) A/R should go into lock-out state,

i.e., it must not reclose after the elapse of dead-time of A/R.

2. As regards over-reaching of Kolar and Nelamangala end relays for

the fault on 400 kV Hoody – Kolar line-2, KPTCL and PGCIL (SR-II)

are recommended to modify the Z1B settings of the relays used

(7SA522) suitably so that they operate with a Zone-2 time delay.

3. KPTCL to check the ICT’s back-up (high-set) protection settings,

and ensure that they operate with a time delay of 100 msec.

4. KPTCL to take steps to replace the solid state relays at Hoody end

on Hoody-Nelamangala lines – 1 & 2 with numerical relays at the

earliest.

KPTCL/

PGCIL (SR-II)

KPTCL Mail recieved dated 25-05-2016:

1. Incorporated. --- Completed.

2. Yet to be informed.

3. With the existing electromechanical relays, it's not possible to add time

delay of 100 mSec. However, ongoing R&M works of Hoody included

complete ICT1 and ICT2 panel replacement having Numerical relays.

4.The solid state relays of Nelamangala-1 and Nelamangala-2 lines will be

replaced by numerical relays for which relays have been identified,Will be

attended in a month's time.

KPTCL Mail recieved dated 28-06-2016:

2. Clarification sought from OEM regarding Z1B settings,PSB settings to

be adopted in Seimens make distance relays. 3. ICT back up

(high set settings are verified and found to be in order. --- Completed.

4.At Hoody, Solid state relays of 400kV Nelamangala 1 &2 lines are

replaced by numerical relays. Now 400kV Nelamangala 1& 2 lines are

provided with ABB, REL 670 and Micom P442 relays. --- Completed.

Pending only

point 2

54/IV/2 For the line under consideration, the following shall be carried out by

TSTRANSCO and PGCL (SR-I) in co-ordination:

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.

Line tripped at Mamidipally end only on

Direct Trip receipt from Ghanapur end

30-04-2016

at 16:40 hrs

Tripping of 400kV

Ghanapur-Mamidapalli line

PGCIL (SR-I)/

TSTRANSCO

Yet to be informed

26-03-2016

at 12:42 hrs


Hoody substation of

KPTCL

53/I/5

Annexure-II

Page 24 of 26

56/III/4 Tripping of 220 kV Sedam-

Tandur line

03-06-2016

at 21:52 hrs

Line tripped on B-phase to earth fault. Auto-

reclose is not enabled for line.

KPTCL and TSTRANSCO to fast-track providing A/R on 220 kV

Sedam – Tandur line, and furnish an action plan of providing the same

by next PCSC meeting (PCSC-57).

KPTCL/

TSTRANSCO



Sedam Substation of

KPTCL.

19-06-2016

at 15:27hrs






failure

KPTCL and TSTRANSCO to take steps to provide A/R feature on 220

kV Sedam – Tandur inter-state line at their respective ends at the

earliest.

KPTCL/

TSTRANSCO

Yet to be informed

56/II/16

Pending

1.TSTRANSCO and SCCL to check drop-off to pick-up ratio of OV

relay and ensure that it is kept at 0.97 & above.

2.TSTRANSCO and SCCL to configure respective end ‘s DR & EL so

that they get triggered on OVR protection, and record relevant events.

3.SCCL to configure Jaipur end relay’s EL properly so that the time-

stamp resolution is extended downwards up to milli-second level.

TSTRANSCO/

SCCL

Yet to be informed PendingTripped on 3-phase Trip at Gajwel end30.06.2016

at 23:43 hrs

Tripping of 400 kV Gajwel-

Singareni line-2

Annexure-II

Page 25 of 26

57/I/1 Complete outage of 220 kV

Karwar Substation of

KPTCL

12-07-2017

at 11:36 hrs

Triggering incident was failure of R phase

PT in Bus-1 at 220kV Karwar substation.

220kV Kaiga-Kodasalli tripped during the

incident. Also bus shut down occurred at

Kadra and Kodasally stations.

1.NPCIL (KAPS) to disable Definite Weak Time O/C relay, and put in

its place by IDMT O/C relay for backup protection on both 220 kV

Kaiga – Kadra line and 220 kV Kaiga – Kodasalli line at Kaiga end.

2.KPTCL to put bus bar protection in service at their 220 kV Karwar

SS at the earliest.

3.KPCL/ KPTCL to implement Weak In-feed Logic with Echo feature

enabled by Under Voltage (27) element on Kadra – Karwar lines 1 & 2.

4.KPTCL to furnish equipment failure report of the current incident to

PSE&TD Division of CEA with a copy marked to SRPC.

KPTCL/ KPCL/ NPCIL

(KAPS)


56/IV/2 For the line under consideration, the following shall be carried out by

APGENCO in coordination with TSTRANSCO:

1.End-to-end communication for DT/ permissive & other signals may

be ensured by testing at both the ends.

2.Healthiness of PLCC system components (hardware and software) at

both ends shall be checked and faulty components shall be repaired/

replaced.

APGENCO/

TSTRANSCO

Yet to be informed PendingDirect Trip was received at VTPS and line

was holding from Suryapet end

13-06-2016

at 16:55 hrs

Tripping of 400 kV VTPS-

Suryapet line

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

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


57/II/6 Tripping of 400 kV

Ramagundam-Malkaram

line

12-07-2016

at 00:13 hrs

Line tripped on operation of overvoltage

protection at Malkaram and Direct Trip was

received at Ramagundam. Over-voltage

operation was observed in EL of Malkaram.

DR not furnished.

1.NTPC-Ramagundam to ensure time sync of their station’s DR & EL

with GPS.

2.NTPC-Ramagundam to sort out overlapping issue of time-stamp in

their station DR’s.

3.TSTRANSCO to set right OVR, Stage-I protection issues at their 400

kV Malakaram SS by taking suitable remedial action.

NTPC/

TSTRANSCO


Annexure-II

Page 26 of 26

Sl.No. Element NameOutage

date/time

Revival

date/time

Reason for

OutageSender/ Receiver Remedial Measures/ Actions taken

1 220 kV NEYVLI - VILLIANUR 05-08-2016/06:02:00 05-08-2016/06:03:00

FAULT TRIPPED

DUE TO DISTANCE

PROTECTION

NLC/PED

NLC:Feeder tripped on Zone1 R-N fault. AR

operated.

PED:

2 220 kV AMBEWADI - PONDA 2 12-08-2016/05:06:00 DPR OPERATED KPTCL/GOA To-be-discussed

3 400 Kv COASTAL - NTPL 12-08-2016/18:32:00 12-08-2016/19:02:00 VT FUSE FAILURE CEPL/NTPL To-be-discussed

4 400/220 kV ICT-2 AT GUTTUR 13-08-2016/09:15:00 13-08-2016/09:42:00NO RELAY

INDICATIONKPTCL To-be-discussed

5 400 kV KOLAR - HOSUR 2 14-08-2016/15:16:00 14-08-2016/19:28:00Y-PH LA FAILURE @

HSR ENDPGCIL(SR-II) To-be-discussed

6 400 Kv SPDR - SVCHATRAM 14-08-2016/13:49:00 14-08-2016/14:07:00DT RECEIVED @

SPDRPGCIL(SR-II)/TANTRANSCO

TANTRANSCO: At the time of 400KV

S.V.Chatram -Alamathy Feeder-2 tripping on

14.08.2016 at 13:49 hrs., 400KV S.V.Chatram

- Sriperumpudur (PGCIL) Feeder tripped on

DEF Protection at PGCIL end only. There was

no tripping of 400kV Sriperumpudur (PGCIL)

feeder at 400kV S.V.Chatram SS on

14.08.2016 at 13:49 hrs.

PGCIL(SR-II):

7 220 kV AMBEWADI - PONDA 1 15-08-2016/12:37:00 15-08-2016/12:52:00 TRANSIENT FAULT KPTCL/GOA To-be-discussed

8 220 kV AMBEWADI - PONDA 1 19-08-2016/13:43:00 19-08-2016/14:02:00TRIPPED ON B-N

FAULTKPTCL/GOA To-be-discussed

Pending Remedial Measures/ Actions taken

for the Critical Tripping Incidents (as on 30.09.2016)

Annexure-III

Page 1 of 7

9 400 kV NEYVELI TS 2 - PUGALUR 21-08-2016/10:35:00 21-08-2016/11:20:00

TRIPPED ON

INSULATOR FLASH

OVER IN NLC2-

NLC2E AT NLC2 S/Y

NLC/PGCIL(SR-II)

NLC: The pugalur end breaker got tripped on

Y-N Zone1 distance fault due to NLC2 to

NLC2E Y Phase insulator flashover. This

caused Pugalur feeder breaker at TS2 end to

trip on overvoltage. DT was sent to Pugalur

end and 3 phase trip was initiated.

10 220 kV AMBEWADI - PONDA 1 21-08-2016/16:22:00TRIPPED ON B-N

FAULTKPTCL/GOA To-be-discussed

11400 kV NEYVELI TS 2 - NEYVELI TS2

EXP21-08-2016/10:35:00

INSULATOR

FLASHOVERNLC

NLC:The feeder got tripped on current

differential due to insulator flash over at TS2

end

12 400/220 kV ICT-1 AT CUDDAPAH 22-08-2016/03:11:00 22-08-2016/05:20:00

220KV BUSBAR

PROTECTION

OPERATED DUE TO

CT BLAST

PGCIL(SR-I)/APTRANSCO

PGCIL(SR-I):Tripped due to operation of

APTRANSCO's Bus-bar protection on 220kV

CT failure at APTRANSCO's 220kV Station

APTRANSCO:

13 400/220 kV ICT-2 AT CUDDAPAH 22-08-2016/03:11:00 22-08-2016/05:23:00

220KV BUSBAR

PROTECTION

OPERATED DUE TO

CT BLAST

PGCIL(SR-I)/APTRANSCO

PGCIL(SR-I):Tripped due to operation of

APTRANSCO's Bus-bar protection on 220kV

CT failure at APTRANSCO's 220kV Station

APTRANSCO:

14 400 Kv TUMKUR - BIDADI 23-08-2016/08:30:00 23-08-2016/12:35:00 TRIPPED ON FAULT PGCIL(SR-II) To-be-discussed

15 400 Kv TUMKUR - BIDADI 23-08-2016/12:46:00 23-08-2016/16:25:00TRIPPED ON R_N

FAULTPGCIL(SR-II) To-be-discussed

16 400 Kv NELAMANGALA - TUMKUR 23-08-2016/09:00:00 23-08-2016/15:27:00 R-N FAULT KPTCL/PGCIL(SR-II) To-be-discussed

17 HVDC GAJUWAKA POLE 1 23-08-2016/13:08:00 23-08-2016/13:44:00

BLOCKED DUE TO

FILTER

UNBALANCE

DURING POLE II

DEBLOCKING

PGCIL(SR-I)PGCIL(SR-I):The pole went to standby mode

due to strucking of B-Phase Tap changer.

18 400/220 kV ICT-3 AT BANGALORE 27-08-2016/11:21:00 TRIPPED KPTCL To-be-discussed

Annexure-III

Page 2 of 7

19 400 kV KAIGA - GUTTUR -1 28-08-2016/11:50:00 28-08-2016/12:35:00 B-N FAULT NPCIL/KPTCL To-be-discussed

20400 Kv KRISHNAPATNAM -

CHITTOOR29-08-2016/21:46:00 29-08-2016/22:07:00 R-N FAULT To-be-discussed

21 400 Kv GOOTY - TUMKUR - 2 31-08-2016/15:13:00 31-08-2016/18:36:00DT RECEIVED

FROM TMKRPGCIL(SR-I)

PGCIL(SR-I):O/V Stage-1 protection operated

at Tumkur end

22 220 kV SABARGIRI - THENI 03-09-2016/10:21:00 03-09-2016/10:48:00 EARTH FAULT KSEB/ TANTRANSCO

TANTRANSCO: Temporary fault. Both Main-1

& 2 at Theni end sensed the fault (B-E, Zone-

2) and executed trip. AR lockout at Theni

end.

KSEB:

23 400 kV VIJAYAWADA - GAZUWAKA- 1 06-09-2016/16:43:00 06-09-2016/17:08:00

ZONE - 2

PROTECTION

OPERATED

APTRANSCO/PGCIL(SR-I)

PGCIL(SR-I):Tripped in Zone-2 due to non-

clearence of substation fault at

APTRANSCO's Kalpaka SUbstation

24 400 kV SIMHADRI - KALPAKKA -3 06-09-2016/16:43:00 06-09-2016/17:17:00BUS-1 FAULT @

KLPAKA ENDNTPC/APTRANSCO To-be-discussed



26 400 kV KALPAKKA - VEMAGIRI -1 06-09-2016/16:43:00 06-09-2016/17:13:00BUS-1 FAULT @

KLPAKA ENDAPTRANSCO To-be-discussed

27 400 kV KALPAKKA - GAZUWAKA -2 06-09-2016/16:43:00 06-09-2016/17:33:00BUS-1 FAULT @

KLPAKA ENDAPTRANSCO/PGCIL(SR-I)




28 400 kV KALPAKKA - GAZUWAKA -1 06-09-2016/16:43:00 06-09-2016/17:32:00BUS-1 FAULT @

KLPAKA ENDAPTRANSCO/PGCIL(SR-I)




29400/220 kV ICT-1 AT

VISAKHAPATNAM06-09-2016/16:43:00 06-09-2016/17:21:00

TRIPPED ON OVER

CURRENT

PROTECTION

APTRANSCO To-be-discussed

30 400/220 kV ICT-1 AT KALPAKA 06-09-2016/16:43:00 06-09-2016/17:14:00BUS-1 FAULT @

KLPAKA ENDAPTRANSCO To-be-discussed

31 400 kV HNPCL- KALPAKKA 1 06-09-2016/16:43:00 06-09-2016/18:08:00BUS-1 FAULT @

KLPAKA ENDHNPCL/APTRANSCO To-be-discussed



Annexure-III

Page 3 of 7

33 400 kV SIMHADRI - KALPAKKA-2 06-09-2016/16:43:00 06-09-2016/16:57:00BUS-1 FAULT @


34 220 kV AMBEWADI - PONDA 1 07-09-2016/13:32:00 07-09-2016/16:03:00 B-N FAULT KPTCL/GOA To-be-discussed

35 220 kV CHITTOR - THIRUVALEM 09-09-2016/10:40:00

BUS BAR

PROTECTION

OPERATED @

220KV CTR END

APTRANSCO/PGCIL(SR-II)

TANTRANSCO: 230kV Thiruvalam – Chittor

feeder has not tripped on 09.09.2016 at

10:40 hrs. at Thiruvalam end since the 230kV

Bus fault at Chittor SS was cleared by Bus Bar

Protection Relay at

Chittor end.

36 400 kV KHAMMAM - KTPS 1 13-09-2016/19:15:00 13-09-2016/21:45:00TRIPPED ON R-PH

FAULTPGCIL(SR-II)/TSGENCO

PGCIL(SR-I):Tripped on Line Fault at KTPS end

only. Line belongs to TSTRANSCO. A/R

sucessful at Khammam (POWERGRID, SR1)

end.

TSGENCO:

37 400/230 kV ICT 5 AT ALAMATHY 14-09-2016/11:13:00 14-09-2016/11:30:00

TRIPPED DUE TO

FAULT ON 230KV

SIDE

TANTRANSCO

TANTRANSCO: Due to passing fault in 230KV

Alamathy-Korattur feeder (AФ), 230KV

ALAMATHY-KORATTUR feeder got tripped at

both ends . At the same time, the feeders

connected in 230KV BUS-B got tripped due

to actuation of 230kV BBP. ICT 4 and ICT 5

were in Bus B. The 230KV Bus-B was

normalized at 11:32 hrs. through 230kV Bus

coupler. All feeders were normalized by

11:48 hrs.

The Bus bar protection scheme will be

tested for healthiness.

38 400 Kv KUDGI- KOLHAPUR-1 14-09-2016/19:36:00 14-09-2016/20:20:00DT RECEIVED AT

KUDGIPGCIL(SR-II) To-be-discussed

Annexure-III

Page 4 of 7

39 400/230 kV ICT 4 AT ALAMATHY 14-09-2016/11:13:00 14-09-2016/11:30:00

TRIPPED DUE TO

FAULT ON 230KV

SIDE

TANTRANSCO







were in Bus B.The 230KV Bus-B was



11:48 hrs.



40 400/230 Kv ICT 3 AT ALAMATHY 15-09-2016/22:14:00 16-09-2016/23:32:00

230 KV BUS BAR

PROTECTION

OPERATED

TANTRANSCO







were in Bus B.The 230KV Bus-B was



11:48 hrs.



41 220 kV SABARGIRI - THENI 16-09-2016/13:50:00 16-09-2016/13:57:00 EARTH FAULT KSEB/ TANTRANSCOTANTRANSCO: Temporary fault. AR

successful at Theni end.

42 400 Kv BTPS - YTPS 16-09-2016/16:55:00 16-09-2016/18:33:00EARTH FAULT

RELAY OPERATEDKPCL To-be-discussed

43 400 Kv RAICHUR - YTPS 16-09-2016/16:55:00 16-09-2016/18:39:00EARTH FAULT

RELAY OPERATEDKPCL To-be-discussed

44400 Kv VTPS STG IV - SATTENAPALLI -

216-09-2016/15:18:00 16-09-2016/16:11:00

EARTH FAULT

RELAY OPERATEDAPGENCO/TSTRANSCO To-be-discussed

Annexure-III

Page 5 of 7

45 400 Kv NCTPS - SVCTM-II 16-09-2016/00:39:00 16-09-2016/01:44:00

TRIPPED AT

SVCHATRAM END

ONLY

TANGEDCO/TANTRANSCO

TANTRANSCO: Temporary fault. AR

successful at NCTPS-II end (A-N fault, Zone-1)

and AR lock out at S.V.Chatram end (A,C-N

fault, Zone-1).

46 400 Kv HASSAN - UPCL- 2 18-09-2016/12:12:00 18-09-2016/12:45:00

TRIPPED DUE TO

DISTANCE

PROTECTION

PGCIL(SR-II)/UPCL/KPTCL To-be-discussed

47 400 Kv NELLORE - SPDR 2 20-09-2016/15:24:00 20-09-2016/18:14:00DISTURBANCE AT

SPDR ENDPGCIL (SR-I)/ PGCIL(SR-II) To-be-discussed

48 400 Kv KAYATHAR - KARAIKUDI -1 20-09-2016/12:10:00 20-09-2016/12:49:00R PHASE TO

GROUND FAULTTANTRANSCO/PGCIL To-be-discussed

49 400 kV N'SAGAR - CUDDAPPA -1 20-09-2016/09:55:00 20-09-2016/15:22:00HOT SPOT AT CVT

DROP JUMPERPGCIL(SR-I) To-be-discussed

50 400/220 kV ICT-1 AT HYDERABAD 21-09-2016/19:10:00 21-09-2016/22:54:00 220KV BUS-1 DEAD PGCIL(SR-I) To-be-discussed

51 400/220 kV ICT-3 AT HYDERABAD 21-09-2016/19:10:00 21-09-2016/22:56:00 220KV BUS-1 DEAD PGCIL(SR-I) To-be-discussed

52 400 kV GHANAPUR - MAMIDIPALLY 21-09-2016/19:10:00 21-09-2016/19:34:00TRIP CIRCUIT

FAULTYPGCIL(SR-I)/TSTRANSCO To-be-discussed

53 400 Kv GAJWEL - SINGARENI-2 22-09-2016/04:17:00

GENERATOR

DIFFERENTIAL

PROTECTION

ACTED

TSTRANSCO/ SCCL To-be-discussed

54 400/220 Kv ICT-3 AT MALKARAM 24-09-2016/01:42:00 OVER FLUX TSTRANSCO To-be-discussed

55 400 kV VIJAYAWADA - VEMAGIRI 3 24-09-2016/11:34:00 24-09-2016/13:12:00DT RECEIVED

FROM NUNNAPGCIL(SR-I)/ APTRANSCO To-be-discussed

56 400/220 Kv ICT-2 AT MALKARAM 24-09-2016/02:48:00 PRV OPERATED TSTRANSCO To-be-discussed

57 400/220 kV ICT-3 AT GAJWEL 24-09-2016/06:57:00 24-09-2016/14:08:00 EARTH FAULT TSTRANSCO To-be-discussed

58 400 Kv JEYPORE - GAZUWAKA -1 25-09-2016/19:12:00 25-09-2016/20:39:00

INTERZONE

PROTECTION

OPERATED

PGCIL(ER-I/ PGCIL (SR1) To-be-discussed

59 HVDC GAJUWAKA POLE 1 25-09-2016/19:12:00 25-09-2016/20:22:00

INTERZONE

PROTECTION

OPERATED

PGCIL(SR-I) To-be-discussed

60400 kV RAMAGUNDAM -

CHANDRAPUR27-09-2016/01:00:00 27-09-2016/02:27:00 B - N FAULT NTPC/PGCIL(SR-I) To-be-discussed

Annexure-III

Page 6 of 7

61 400/230 kV ICT-2 AT MADURAI 28-09-2016/20:25:00 29-09-2016/21:23:00 220 KV SIDE FAULT PGCIL (SR-II) To-be-discussed

62400/220 kV ICT-1 AT

VISAKHAPATNAM28-09-2016/23:03:00 28-09-2016/23:50:00 220 KV SIDE FAULT PGCIL (SR-I) To-be-discussed

63 400/230 kV ICT-1 AT MADURAI 28-09-2016/20:25:00 29-09-2016/21:27:00 220 KV SIDE FAULT PGCIL (SR-II) To-be-discussed

Annexure-III

Page 7 of 7

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