guidelines relay setting
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MODEL SETTING CALCULATIONS FOR TYPICAL IEDs
LINE PROTECTION SETTING GUIDE LINES
PROTECTION SYSTEM AUDIT CHECK LIST
RECOMMENDATIONS FOR PROTECTION MANAGEMENT
SUB-COMMITTEE ON RELAY/PROTECTION UNDER TASK
FORCE FOR POWER SYSTEM ANALYSIS UNDER
CONTIGENCIES
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Protection subcommittee report
Preamble
As a follow up of one of the recommendations of the Enquiry Committee headed by Chairman,CEA on grid disturbances that took place in Indian grid on 30th and 31st July 2012, Ministry of
Power constituted a Task Force on Power System Analysis under Contingencies in December
2012. The Terms of Reference of Task Force broadly cover analysis of the network behaviour
under normal conditions and contingencies, review of the philosophy of operation of protection
relays, review of islanding schemes and technological options to improve the performance of
the grid.
Apart from the main Task Force two more sub-committees were constituted. One for system
studies for July-September 2013 conditions and another for examining philosophy of relay and
protection coordination.
The tasks assigned to the protection sub-committee were to review the protection setting
philosophy (including load encroachment, power swing blocking, out of step protection, back-up
protections) for protection relays installed at 765kV, 400kV, 220kV (132kV in NER) transmission
system and prepare procedure for protection audit. This was submitted to the Task Force on
22.07.2013.
Further one more task assigned to the protection sub-committee was to prepare model setting
calculations for typical IEDs used in protection of 400kV line, transformer, reactor and busbar.
This document gives the model setting calculations, line protection setting guide lines,
protection system audit check lists, recommendations for protection system management and
some details connected with protection audit.
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Acknowledgement
The Protection sub-committee thanks members of Task Force for Power System Analysis
under Contingencies for all the support and encouragement. Further the Protection sub-
committee acknowledges the contribution from Mr Rajil Srivastava, Mr Abhay Kumar, Mr
Kailash Rathore of Power Grid, Mr Shaik Nadeem of ABB and Mr Vijaya Kumar of PRDC to the
work carried out by the sub - committee.
Sub-committee
Convener
B.S. Pandey, Power Grid
Members
P. P. Francis, NTPC
S.G. Patki, Tata Power
R. H. Satpute, MSETCL
Nagaraja, PRDC
Bapuji Palki, ABBVikas Saxena, Jindal Power
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LIST OF CONTENTS
PreambleSection Description Pages
1 : Introduction 1-3
2 : Model setting calculations -Line 1-149
3 : Model setting calculations-Transformer 1-132
4 : Model setting calculations- Shunt Reactor 1-120
5 : Model setting calculations- Busbar 1-15
6 : Relay setting guide lines for transmission lines 1-19
7 : Recommendations for protection system management 1-5
8 : Check list for audit of fault clearance system 1-16
9 : Details of protection audit 1-5
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MODEL SETTING CALCULATION DOCUMENTS FOR
TYPICAL IEDs USED FOR THE PROTECTION OF DIFFERENT
POWER SYSTEM ELEMENTS IN 220kV, 400kV AND 765 kV
SUBSTATIONS
INTRODUCTION
In addition to setting criteria guide lines prepared by Subcommittee on relay/protection under
Task Force for Power System Analysis under Contingencies for 220kV, 400kV and 765kV
transmission lines, the Subcommittee has prepared model setting calculation documents for
IEDs used for protection of following elements.
400kV Transmission line
400/220/33kV Auto Transformer
400kV Shunt Reactor
400kV Bus Bar
While guide lines as finalized by the Subcommittee have been used for the setting calculation
document on transmission lines, for other power system elements like transformer, shunt
reactor and bus bar, guide lines as given in CBIP documents and manufacturer's manuals have
been used. The documents presented should serve as a model to various utilities in preparing
similar documents for different power system elements that are used in 220kV, 400kV and
765kV EHV and UHV transmission systems. The documents are prepared to meet following
expectations given in the Protection subcommittee report.
The numerical terminals referred as IED (Intelligent electronic device) contain apart from main
protection functions several other protection & supervision functions which may or may not be
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and Control functions. It is also recommended that graphical representation of distance relay
zones on R-X plane including phase selection, load encroachment & power swing
characteristics should be done showing exact setting calculated.
Each of these documents has following main sections:
1. BASIC SYSTEM PARAMETERS: This section contains all the system related information
including single line diagram that will be required in carrying out the setting calculations andthus form an important part. This information is unique to each element like line, transformer,
reactor or busbar. This helps not only in carrying out the setting calculations; it also helps in
future, if there is a need to revisit this data.
2. TERMINAL IDENTIFICATION AND LIST OF FUNCTIONS: This section contains brief details
of the IED and lists all the functions that are available in the IED and clearly identifies the ones
which are activated and those that are required to be set. Thus this section serves as a checklist
of all the functions used and gives a quick overview of functions that needs to be set.
3. SETTING CALCULATIONS AND RECOMMENDED SETTINGS: This section contains
subsections viz., Setting guide lines, Setting calculations and Recommended settings for each
function.
Setting guidelines:This subsection contains guide lines for each of the parameter to be set for
the function. The guidelines are taken from the report prepared by Protection subcommittee and
CBIP guide lines mentioned in the report. In addition to the main settings the IED also has
various other settings that need to be set. Guide lines for these settings are taken mainly from
manufacturer's user manuals and these are also given here in brief. In such instances, where
the setting is straight forward and does not involve any calculations, the recommended value
are given and where applicable the reasoning for the adopted setting is given. Settingcalculation based on the relay type, relay function is a major concern for utilities and
understanding each setting and basis for setting helps in arriving at right settings. Further the
guide lines help not only in carrying out the setting calculations, but also help in future, if
there is a need to revisit the settings to take corrective actions in case of any mal-operations
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mal-operations (if excel based sheets with macros are used for setting calculations, they should
be used cautiously in a transparent manner and explained the reasoning associated with
macros / formulae).
Recommended settings: This subsection details recommended setting list with settings for all
the parameters. Settings given in this section need to be used by site engineer for setting the
IED.
It is recommended that these model setting calculations are reviewed periodically to take care ofany changes in manufacturer's design, use of simulation tools, RTDS, or better understanding
of settings and guidelines etc. It is also recommended that setting calculation documents are
prepared for IEDs of different manufacturers that are used in the system.
Disclaimer: The model setting calculations and recommended settings presented in this
document are for the specific case considered here. Further, the make of the relay considered is
also for illustration purpose only. In the settings which do not require any calculations based on
network data, few of the settings may need review for other practical cases. For settings that
require calculations, power system network data pertaining to respective cases is to be
considered. However, the methodology adopted in this example shall be used for calculating the
line and other equipment protection relay settings and arriving at list of recommended settings.
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MODEL SETTING CALCULATION DOCUMENT FOR A TYPICAL
IED USED FOR TRANSMISSION LINE PROTECTION
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Model setting calculation document for Transmission Line
TABLE OF CONTENTS
TABLE OF CONTENTS...............................................................................................................2
1.0 BASIC SYSTEM PARAMETERS .........................................................................................8
1.1 Network line diagram of the protected line and adjacent circuits ...................................8
1.2 Single line diagram of the double circuit line....................................................................9
1.3 Line parameters ..................................................................................................................9
2.0 TERMINAL IDENTIFICATION AND LIST OF FUNCTIONS................................................10
2.1 REL670...............................................................................................................................10
2.1.1 Terminal Identification..........................................................................................102.1.2 List of functions available and those used............................................................10
2.2 REC670 ..............................................................................................................................16
2.2.1 Terminal identification..........................................................................................162.2.2 List of functions available and those used............................................................16
3.0 SETTING CALCULATIONSAND RECOMMENDED SETTINGS FOR REL670.................23
3.1 REL670...............................................................................................................................23
3.1.1 Analog Inputs.......................................................................................................233.1.2 Local Human-Machine Interface ..........................................................................263.1.3 Indication LEDs....................................................................................................263.1.4 Time Synchronization ..........................................................................................283.1.5 Parameter Setting Groups ...................................................................................313.1.6 Test Mode Functionality TEST.............................................................................32
3.1.7
IED Identifiers......................................................................................................34
3.1.8 Rated System Frequency PRIMVAL....................................................................353.1.9 Signal Matrix For Analog Inputs SMAI .................................................................353.1.10 General settings of Distance protection zones.....................................................373.1.11 Distance Protection Zone, Quadrilateral Characteristic (Zone 1) ZMQPDIS.........393.1.12 Distance Protection Zone, Quadrilateral Characteristic (Zone 2) ZMQAPDIS .....443.1.13 Distance Protection Zone, Quadrilateral Characteristic (Zone 3) ZMQAPDIS ......473.1.14 Distance Protection Zone, Quadrilateral Characteristic (Zone 5) ZMQAPDIS ......503.1.15 Phase Selection with Load Encroachment, Quadrilateral Characteristic FDPSPDIS
543.1.16 Broken Conductor Check BRCPTOC (Normally used for Alarm purpose only) ....623.1.17 Tripping Logic SMPPTRC....................................................................................633.1.18 Trip Matrix Logic TMAGGIO.................................................................................653.1.19 Automatic Switch Onto Fault Logic, Voltage And Current Based ZCVPSOF........663.1.20 Power Swing Detection ZMRPSB........................................................................68
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3.2.1 Analog Inputs.......................................................................................................933.2.2 Local Human-Machine Interface ..........................................................................95
3.2.3 Indication LEDs....................................................................................................963.2.4 Time Synchronization ..........................................................................................973.2.5 Parameter Setting Groups .................................................................................1013.2.6 Test Mode Functionality TEST...........................................................................1023.2.7 IED Identifiers....................................................................................................1033.2.8 Rated System Frequency PRIMVAL..................................................................1033.2.9 Signal Matrix For Analog Inputs SMAI ...............................................................1033.2.10 Synchrocheck function (SYN1) ..........................................................................1063.2.11 Autorecloser SMBRREC....................................................................................1103.2.12 Disturbance Report DRPRDRE .........................................................................118
APPENDIX-A: COORDINATION OF 400KV LINE PROTECTION ZONE-2 AND ZONE-3 WITH
IDMT O/C & E/F RELAYS OF 400KV SIDE OF ICT AND 220KV LINE................................... 121
APPENDIX-B: EFFECT OF NETWORK CHANGE DUE TO A LINE LILO ON RELAY
SETTINGS OF LILO LINE & ADJACENT LINES.................................................................... 131
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LIST OF FIGURES
Figure 1-1: Network line diagram of the protected line ....................................................................................... 8Figure 1-2: Equivalent representation of the protected line with source impedance .......................................... 9Figure 3-1: Setting angles for discrimination of forward and reverse fault........................................................ 37Figure 3-2: Characteristic for phase-to-earth measuring, ohm/loop domain..................................................... 39Figure 3-3: Characteristic for phase-to-phase measuring................................................................................. 40Figure 3-4: Relation between distance protection ZMQPDIS and FDPSPDIS for phase-to-earth faultloop>60........................................... ............................................................................................................... 54Figure 3-5: Relation between distance protection (ZMQPDIS) and FDPSPDIS characteristic for phase-to-phase fault for line>60........................................... ........................................................................................ 55
Figure 3-6: Load encroachment characteristic .................................................................................................. 56Figure 3-7: Operating characteristic for ZMRPSB function ............................................................................... 68Figure 3-8: Characteristics for Phase to Phase faults ....................................................................................... 75Figure 3-9: Characteristics for Phase to Earth faults ........................................................................................ 76
Figure A-1: System details for the network under consideration for relay setting........................................... 123Figure A-2: 3-Ph fault current for 220 kV side fault ......................................................................................... 124Figure A-3: Over Current Relay Curve Co-ordination and Operating Time .................................................... 125Figure A-4: Ph-G fault current for 220 kV side fault ........................................................................................ 126
Figure A-5: Earth Fault Relay Curve Co-ordination and Operating Time ....................................................... 127Figure A-6: Earth fault relay co-ordination for 400 kV bus fault at Station B (Remote bus of the protected line)......................................................................................................................................................................... 128Figure A-7: Earth fault relay operating time co-ordinated with Zone 3 time setting ....................................... 129
Figure B-1: Network line diagram of the system after the LILO of one circuit of line AB................................ 131Figure B-2: SLG Fault at bus B with source at Station A and Line A-S out of service and Earthed ............... 134Figure B-3: SLG Fault at bus B with sources at Station A & B and Line A-S out of service and Earthed ...... 135Figure B-4: SLG Fault at bus B with sources at Station A, B & S and Line A-S out of service and Earthed .. 136
Figure B-5: SLG Fault at bus B with source at Station A and Line B-S out of service and Earthed ............... 137
Figure B-6: SLG Fault at bus B with sources at Station A & B and Line B-S out of service and Earthed ...... 138Figure B-7: SLG Fault at bus B with sources at Station A, B & S and Line B-S out of service and Earthed .. 139Figure B-8: SLG Fault at bus S with source at Station A and Line A-B out of service and Earthed ............... 140Figure B-9: SLG Fault at bus S with sources at Station A & B and Line A-B out of service and Earthed ...... 141Figure B-10: SLG Fault at bus S with sources at Station A, B & S and Line A-B out of service and Earthed 142Figure B-11: SLG Fault at bus B with source at Station A .............................................................................. 143Figure B-12: SLG Fault at bus B with sources at Station A and B.................................................................. 144Figure B-13: SLG Fault at bus B with sources at Station A, B & S ................................................................. 145Figure B-14: SLG Fault at bus S with source at Station A .............................................................................. 146
Figure B-15: SLG Fault at bus S with sources at Station A and B.................................................................. 147Figure B-16: SLG Fault at bus S with sources at Station A, B & S ................................................................. 148
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LIST OF TABLES
Table 2-1: List of functions in REL670 .......................................................................................................... 10Table 2-2: List of functions in REC670 .......................................................................................................... 16Table 3-1: Analog inputs ................................................................................................................................. 24Table 3-2: Local human machine interface ....................................................................................................... 26Table 3-3: LEDGEN Non group settings (basic) ............................................................................................... 27Table 3-4: Time synchronization settings.......................................................................................................... 29Table 3-5: Parameter setting group................................................................................................................... 32Table 3-6: Test mode functionality .................................................................................................................... 34Table 3-7: IED Identifiers ................................................................................................................................... 34
Table 3-8: Rated system frequency .................................................................................................................. 35Table 3-9: Signal Matrix For Analog Inputs ....................................................................................................... 36Table 3-10: General settings for distance protection ........................................................................................ 38Table 3-11: ZONE 1 Settings ............................................................................................................................ 43Table 3-12: ZONE 2 Settings ............................................................................................................................ 46Table 3-13: ZONE 3 Settings........................................................................................................................... 49Table 3-14: ZONE 5 Settings........................................................................................................................... 52Table 3-15: Phase Selection with Load Encroachment, Quadrilateral Characteristic ...................................... 61Table 3-16: Broken Conductor Check ............................................................................................................... 63Table 3-17: Tripping Logic................................................................................................................................. 64Table 3-18: Trip Matrix Logic............................................................................................................................. 65Table 3-19: Automatic Switch Onto Fault Logic ................................................................................................ 67Table 3-20: Power Swing Detection ............................................................................................................... 73Table 3-21: Scheme Communication Logic For Distance Or Overcurrent Protection ...................................... 77Table 3-22: Stub Protection............................................................................................................................... 78Table 3-23: Fuse Failure Supervision ............................................................................................................... 79Table 3-24: Four Step Residual Overcurrent Protection ................................................................................... 83Table 3-25: Two Step Overvoltage Protection .................................................................................................. 86Table 3-26: Setting of fault locator values ......................................................................................................... 89
Table 3-27: Disturbance Report ........................................................................................................................ 92Table 3-28: Analog Inputs ................................................................................................................................. 93Table 3-29: Local human machine interface ..................................................................................................... 96Table 3-30: LEDGEN Non group settings (basic) ............................................................................................. 96Table 3-31: Time Synchronization..................................................................................................................... 99Table 3-32: Parameter Setting Groups ........................................................................................................... 102Table 3-33: Test Mode Functionality ............................................................................................................... 102Table 3-34: IED Identifiers ............................................................................................................................... 103Table 3-35: Rated System Frequency............................................................................................................. 103
Table 3-36: Signal Matrix For Analog Inputs ................................................................................................... 105
Table 3-37: Synchrocheck function ................................................................................................................. 108Table 3-38: Autorecloser ................................................................................................................................. 116Table 3-39: Disturbance Report ...................................................................................................................... 119Table A-1 Settings of Over current and Earth fault relays............................................................................... 122Table B-1: Fault At Station-B With Source At Station A and Line A-S Earthed........................................... 134Table B-2: Fault At Station-B With Sources At Station A & B and Line A-S Earthed .......................... 135
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Table B-13: Fault At Station-S With Sources At Station A & B .................................................................... 147Table B-14: Fault At Station-S With Sources At Station A, B & S................................................................ 148
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SETTING CALCULATION EXAMPLE
SUB-STATION: Station-A
FEEDER: 400kV OHL from Station-A to Station-B
PROTECTION ELEMENT: Main-I Protection
Protection schematic Drg. Ref. No. XXXXXX
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1.0 BASIC SYSTEM PARAMETERS
1.1 Network line diagram of the protected line and adjacent circuitsThe network line diagram (Figure 1-1) of the system under consideration showing
protected line along with adjacent associated elements should be collected. The
network diagram should indicate the voltage level, line length, transformer/generator
rated MVA & fault contributions of each element for 3-ph fault at station-A and for
3-ph fault at Station-B.
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1.2 Single line diagram of the double circuit line
Equivalent representation of the protected line based on network line diagram indicated at Figure 1-1 is prepared as shown in Figure 1-2 indicating the source fault impedance at station-A and Station-
B, positive and zero sequence impedance of the protected line.
Figure 1-2: Equivalent representation of the protected line with source impedance
1.3 Line parameters
Line: Substation-A to Substation-B
Frequency: 50Hz
Line data: R1 + jX1 = 0.0288 + j0.307 /km
R0 + jX0 = 0.2689 + j1.072 /km
R0M + jX0M = 0.228 + j0.662 /km
Line length: 190km
CT ratio: 1000/1A
CVT ratio: 400/0.11kV
Maximum expected load on line both import and export: This shall be obtained from the load flowanalysis of the power system under all possible contingency. From the load flow studies, 1500MVA
is the maximum expected load under worst contingency on this line at 90% system voltage.
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2.0 TERMINAL IDENTIFICATION AND LIST OF FUNCTIONS
The various functions required for the line protection are divided in two IEDs namely REL670 and
REC670 for the purpose of illustration. The terminal identification of this and list of various functions
available in these IEDs are given in this section.
2.1 REL670
2.1.1 Terminal Identification
Station Name: Station-A
Object Name: 400kV OHL from Station-A to Station-B
Unit Name: REL670 (Ver 1.2)
Relay serial No: XXXXXXXX
Frequency: 50Hz
Aux voltage: 220V DC
2.1.2 List of functions available and those used
Table 2-1 gives the list of functions/features available in REL670 relay and also indicates the
functions/feature for which settings are provided in this document. The functions/feature are
indicative and varies with IED ordering code & IED application configuration.
Table 2-1: List of functions in REL670
Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
1 Analog Inputs YES
2 Local Human-Machine Interface YES
3 Indication LEDs YES
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Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
8 Change Lock CHNGLCK NO
9 IED Identifiers YES
10 Product Information YES
11 Rated System Frequency PRIMVAL YES
12 Signal Matrix For Binary Inputs SMBI YES
13 Signal Matrix For Binary Outputs SMBO YES
14 Signal Matrix For mA Inputs SMMI NO
15 Signal Matrix For Analog Inputs SMAI YES
16 Summation Block 3 Phase 3PHSUM NO
17 Authority Status ATHSTAT NO
18 Denial Of Service DOS NO
19
Distance Protection Zone, Quadrilateral
Characteristic (Zone 1) ZMQPDIS YES
20Distance Protection Zone, Quadrilateral
Characteristic (Zone 2) ZMQAPDISYES
21Distance Protection Zone, Quadrilateral
Characteristic (Zone 3) ZMQAPDISYES
22Distance Protection Zone, Quadrilateral
Characteristic (Zone 4) ZMQAPDISNO
23Distance Protection Zone, Quadrilateral
Ch i i (Z 5) ZMQAPDISYES
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Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
27Automatic Switch Onto Fault Logic, VoltageAnd Current Based ZCVPSOF
YES
28Instantaneous Phase Overcurrent ProtectionPHPIOC
NO
29 Four Step Phase Overcurrent ProtectionOC4PTOC
NO
30Instantaneous Residual Overcurrent ProtectionEFPIOC
NO
31Four Step Residual Overcurrent ProtectionEF4PTOC
YES
32Sensitive Directional Residual Overcurrent AndPower Protection SDEPSDE
NO
33Thermal Overload Protection, One TimeConstant LPTTR
NO
34 Stub Protection STBPTOC YES
35 Broken Conductor Check BRCPTOC YES
36 Two Step Undervoltage Protection UV2PTUV YES
37 Two Step Overvoltage Protection OV2PTOV YES
38 Loss Of Voltage Check LOVPTUV NO
39 General Current And Voltage ProtectionCVGAPC-4 functions NO
40 Current Circuit Supervision CCSRDIF NO
41 Fuse Failure Supervision SDDRFUF YES
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Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
45 Generic Double Point Function Block DPGGIO NO
46Single Point Generic Control 8 SignalsSPC8GGIO
NO
47
Automationbits, Command Function For
DNP3.0 AUTOBITS NO
48 Single Command, 16 Signals SINGLECMD NO
49Scheme Communication Logic For Distance OrOvercurrent Protection ZCPSCH
YES
50Current Reversal And Weak-End Infeed Logic
For Distance Protection ZCRWPSCH
NO
51 Local Acceleration Logic ZCLCPLAL NO
52 Direct Transfer Trip Logic YES
53Low Active Power And Power Factor ProtectionLAPPGAPC
NO
54 Compensated Over and UndervoltageProtection COUVGAPC
NO
55Sudden Change in Current VariationSCCVPTOC
NO
56 Carrier Receive Logic LCCRPTRC NO
57Negative Sequence Overvoltage ProtectionLCNSPTOV NO
58Zero Sequence Overvoltage ProtectionLCZSPTOV
NO
Negative Sequence Overcurrent Protection
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Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
63 Tripping Logic SMPPTRC YES
64 Trip Matrix Logic TMAGGIO YES
65 Configurable Logic Blocks NO
66 Fixed Signal Function Block FXDSIGN NO
67 Boolean 16 To Integer Conversion B16I NO
68
Boolean 16 To Integer Conversion With LogicNode
Representation B16IFCVI
NO
69 Integer To Boolean 16 Conversion IB16 NO
70
Integer To Boolean 16 Conversion With LogicNode
Representation IB16FCVB
NO
71 Measurements CVMMXN YES
72 Phase Current Measurement CMMXU YES
73 Phase-Phase Voltage Measurement VMMXU YES
74Current Sequence Component MeasurementCMSQI
YES
75 Voltage Sequence Measurement VMSQI YES
76 Phase-Neutral Voltage Measurement VNMMXU NO
77 Event Counter CNTGGIO YES
78 Event Function EVENT YES
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Sl.No. Function/features available In REL670
Function/featureactivated
Yes/No
RecommendedSettingsprovided
83 Event List YES
84 Indications YES
85 Event Recorder YES
86 Trip Value Recorder YES
87 Disturbance Recorder YES
88 Pulse-Counter Logic PCGGIO NO
89Function For Energy Calculation And DemandHandling ETPMMTR
NO
90 IEC 61850-8-1 Communication Protocol NO
91IEC 61850 Generic Communication I/OFunctions SPGGIO, SP16GGIO
NO
92IEC 61850-8-1 Redundant Station BusCommunication
NO
93 IEC 61850-9-2LE Communication Protocol NO
94 LON Communication Protocol NO
95 SPA Communication Protocol NO
96 IEC 60870-5-103 Communication Protocol NO
97
Multiple Command And TransmitMULTICMDRCV,
MULTICMDSND
NO
98 Remote Communication NO
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2.2 REC670
2.2.1 Terminal identification
Station Name: Station-A
Object Name: 400kV OHL
Unit Name: REC670 (Ver 1.2)
Relay serial No: XXXXX
Frequency: 50Hz
Aux voltage: 220V DC
2.2.2 List of functions available and those used
Table 2-2 gives the list of functions/features available in REC670 relay and also indicates the
functions/feature for which settings are provided in this document. The functions/feature are
indicative and varies with IED ordering code & IED application configuration.
Table 2-2: List of functions in REC670
Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettingsprovided
1 Analog Inputs YES
2 Local Human-Machine Interface YES
3 Indication LEDs YES
4 Self supervision with internal event list YES
5 Time Synchronization YES
6 Parameter Setting Groups YES
7 Test Mode Functionality TEST YES
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettingsprovided
12 Signal Matrix For Binary Inputs SMBI YES
13 Signal Matrix For Binary Outputs SMBO YES
14 Signal Matrix For Ma Inputs SMMI NO
15 Signal Matrix For Analog Inputs SMAI YES
16 Summation Block 3 Phase 3PHSUM NO
17 Authority Status ATHSTAT NO
18 Denial Of Service DOS NO
19 Differential Protection HZPDIF NO
20Instantaneous Phase Overcurrent ProtectionPHPIOC
NO
21Four Step Phase Overcurrent ProtectionOC4PTOC
NO
22Instantaneous Residual Overcurrent
Protection EFPIOCNO
23Four Step Residual Overcurrent ProtectionEF4PTOC
NO
24Four step directional negative phasesequence overcurrent protection NS4PTOC
NO
25Sensitive Directional Residual OvercurrentAnd Power Protection SDEPSDE NO
26Thermal Overload Protection, One TimeConstant LPTTR
NO
Thermal overload protection two time
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettings
provided
31Directional Underpower ProtectionGUPPDUP
NO
32Directional Overpower ProtectionGOPPDOP
NO
33 Broken Conductor Check BRCPTOC NO
34 Capacitor bank protection CBPGAPC NO
35Two Step Undervoltage ProtectionUV2PTUV
NO
36 Two Step Overvoltage Protection OV2PTOV NO
37Two Step Residual Overvoltage ProtectionROV2PTOV
NO
38 Voltage Differential Protection VDCPTOV NO
39 Loss Of Voltage Check LOVPTUV NO
40 Underfrequency Protection SAPTUF NO
41 Overfrequency Protection SAPTOF NO
42Rate-Of-Change Frequency ProtectionSAPFRC
NO
43General Current and Voltage ProtectionCVGAPC
NO
44 Current Circuit Supervision CCSRDIF NO
45 Fuse Failure Supervision SDDRFUF NO
46Synchrocheck, Energizing Check, AndSynchronizing SESRSYN
YES
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettings
provided
50Logic Rotating Switch For FunctionSelection And LHMI Presentation SLGGIO
NO
51 Selector Mini Switch VSGGIO NO
52Generic Double Point Function Block
DPGGIONO
53Single Point Generic Control 8 SignalsSPC8GGIO
NO
54Automationbits, Command Function ForDNP3.0 AUTOBITS
NO
55 Single Command, 16 Signals SINGLECMD NO
56Scheme Communication Logic For DistanceOr Overcurrent Protection ZCPSCH
NO
57Phase Segregated Scheme CommunicationLogic For Distance Protection ZC1PPSCH
NO
58Current Reversal And Weak-End Infeed
Logic For Distance Protection ZCRWPSCHNO
59 Local Acceleration Logic ZCLCPLAL NO
60Scheme Communication Logic For ResidualOvercurrent Protection ECPSCH
NO
61Current Reversal And Weak-End InfeedLogic For Residual Overcurrent ProtectionECRWPSCH
NO
62Current Reversal And Weak-End InfeedLogic For Phase SegregatedCommunication ZC1WPSCH
NO
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettings
provided
66Sudden Change In Current VariationSCCVPTOC
NO
67 Carrier Receive Logic LCCRPTRC NO
68Negative Sequence Overvoltage Protection
LCNSPTOVNO
69Zero Sequence Overvoltage ProtectionLCZSPTOV
NO
70Negative Sequence Overcurrent ProtectionLCNSPTOC
NO
71Zero Sequence Overcurrent ProtectionLCZSPTOC NO
72 Three Phase Overcurrent LCP3PTOC NO
73 Three Phase Undercurrent LCP3PTUC NO
74 Tripping Logic SMPPTRC NO
75 Trip Matrix Logic TMAGGIO NO
76 Configurable Logic Blocks NO
77 Fixed Signal Function Block FXDSIGN NO
78 Boolean 16 To Integer Conversion B16I NO
79
Boolean 16 To Integer Conversion WithLogic Node
Representation B16IFCVI
NO
80 Integer To Boolean 16 Conversion IB16 NO
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettings
provided
84Phase-Phase Voltage MeasurementVMMXU
YES
85Current Sequence ComponentMeasurement CMSQI
YES
86 Voltage Sequence Measurement VMSQI YES
87Phase-Neutral Voltage MeasurementVNMMXU
NO
88 Event Counter CNTGGIO YES
89 Event Function EVENT YES
90 Logical Signal Status Report BINSTATREP NO
91 Fault Locator LMBRFLO NO
92Measured Value Expander BlockRANGE_XP
NO
93 Disturbance Report DRPRDRE YES
94 Event List YES
95 Indications YES
96 Event Recorder YES
97 Trip Value Recorder YES
98 Disturbance Recorder YES
99 Pulse-Counter Logic PCGGIO NO
100Function For Energy Calculation AndDemand Handling ETPMMTR
NO
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Sl.No. Functions/Feature available In REC670
Features/Functionsactivated
Yes/No
RecommendedSettings
provided
104 IEC 61850-9-2LE Communication Protocol NO
105 LON Communication Protocol NO
106 SPA Communication Protocol NO
107 IEC 60870-5-103 Communication Protocol NO
108
Multiple Command And TransmitMULTICMDRCV,
MULTICMDSND
NO
109 Remote Communication NO
Note: For setting parameters provided in the function listed above, refer section 3 of
application manual 1MRK511230-UEN, version 1.2.
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3.0 SETTING CALCULATIONS AND RECOMMENDED
SETTINGS FOR REL670
The various functions required for the line protection are divided in two IEDs namely REL670 and
REC670. The setting calculations and recommended settings for various functions available in
these IEDs are given in this section.
3.1 REL670
3.1.1 Analog Inputs
Guidelines for Settings:
Configure analog inputs:
Current analog inputs as:
Ch 1 Ch 2 Ch 3 Ch 4 Ch 5 Ch 6
Name# IL1-CB1 IL2-CB1 IL3-CB1 IL1-CB2 IL2-CB2 IL3-CB2
CTprim 1000A 1000A 1000A 1000A 1000A 1000A
CTsec 1A 1A 1A 1A 1A 1A
CTStarPoint parameter indicates the CT secondary winding neutral earthing towards object
(ToObject) or towards busbar (FromObject).
Voltage analog input as:
Ch 1 Ch 2 Ch 3 Ch 4 Ch 5 Ch 6
Name# UL1 UL2 UL3 UL2BUS1 UL2BUS2 UL2L2
VTprim 400kV 400kV 400kV 400kV 400kV 400kV
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Recommended Settings:
Table 3-1 gives the recommended settings for the analog inputs.
Table 3-1: Analog inputs
SettingParameter
DescriptionRecommended
Settings Unit
PhaseAngleRefReference channel for phase angle
PresentationTRM40-Ch1 -
CTStarPoint1ToObject= towards protected object,
FromObject= the oppositeToObject -
CTsec1 Rated CT secondary current 1 A
CTprim1 Rated CT primary current 1000 A
CTStarPoint2ToObject= towards protected object,
FromObject= the oppositeToObject -
CTsec2 Rated CT secondary current 1 A
CTprim2 Rated CT primary current 1000 A
CTStarPoint3
ToObject= towards protected object,
FromObject= the opposite ToObject -
CTsec3 Rated CT secondary current 1 A
CTprim3 Rated CT primary current 1000 A
CTStarPoint4ToObject= towards protected object,
FromObject= the oppositeToObject -
CTsec4 Rated CT secondary current 1 A
CTprim4 Rated CT primary current 1000 A
ToObject towards protected object
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ode sett g ca cu at o docu e t o a s ss o e
SettingParameter
DescriptionRecommended
Settings Unit
FromObject= the opposite
CTsec6 Rated CT secondary current 1 A
CTprim6 Rated CT primary current 1000 A
VTsec7 Rated VT secondary voltage 110 V
VTprim7 Rated VT primary voltage 400 kV
VTsec8 Rated VT secondary voltage 110 V
VTprim8 Rated VT primary voltage 400 kV
VTsec9 Rated VT secondary voltage 110 V
VTprim9 Rated VT primary voltage 400 kV
VTsec10 Rated VT secondary voltage 110 V
VTprim10 Rated VT primary voltage 400 kV
VTsec11 Rated VT secondary voltage 110 V
VTprim11 Rated VT primary voltage 400 kV
VTsec12 Rated VT secondary voltage 110 V
VTprim12 Rated VT primary voltage 400 kV
Binary input module (BIM) Settings
Operation OscBlock(Hz) OscRelease(Hz)I/O Module 1 On 40 30 Pos Slot3
I/O Module 2 On 40 30 Pos Slot3
I/O Module 3 On 40 30 Pos Slot3
I/O Module 4 On 40 30 Pos Slot3
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g
3.1.2 Local Human-Machine Interface
Recommended Settings:Table 3-2 gives the recommended settings for Local human machine interface.
Table 3-2: Local human machine interface
SettingParameter
DescriptionRecommended
Settings Unit
Language Local HMI language English -
DisplayTimeout Local HMI display timeout 60 Min
AutoRepeatActivation of auto-repeat (On) or not(Off)
On -
ContrastLevel Contrast level for display 0 %
DefaultScreen Default screen 0 -
EvListSrtOrder Sort order of event list Latest on top -
SymbolFont Symbol font for Single Line Diagram IEC -
3.1.3 Indication LEDs
Guidelines for Settings:
This function block is to control LEDs in HMI.
SeqTypeLED1: Normally this parameter is set to LatchedAck-S-F. When trip occurs, it will glow
steady and latched till manually reset. When manually reset, it will go OFF when trip is not there. Iftrip still persist, it will f lash.
tRestart: Not applicable for the above case.
tMax:Not applicable for the above case.
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Recommended Settings:
Table 3-3 gives the recommended settings for Indication LEDs.
Table 3-3: LEDGEN Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
Operation Operation mode for the LED function On -
tRestart Defines the disturbance length 0.0 s
tMaxMaximum time for the definition of a
disturbance0.0 s
SeqTypeLED1 Sequence type for LED 1 LatchedAck-S-F -
SeqTypeLED2 Sequence type for LED 2 LatchedAck-S-F -
SeqTypeLED3 Sequence type for LED 3 LatchedAck-S-F -
SeqTypeLED4 Sequence type for LED 4 LatchedAck-S-F -
SeqTypeLED5 Sequence type for LED 5 LatchedAck-S-F -
SeqTypeLED6 Sequence type for LED 6 LatchedAck-S-F -
SeqTypeLED7 Sequence type for LED 7 LatchedAck-S-F -
SeqTypeLED8 Sequence type for LED 8 LatchedAck-S-F -
SeqTypeLED9 Sequence type for LED 9 LatchedAck-S-F -
SeqTypeLED10 Sequence type for LED 10 LatchedAck-S-F -
SeqTypeLED11 Sequence type for LED 11 LatchedAck-S-F -
SeqTypeLED12 Sequence type for LED 12 LatchedAck-S-F -
SeqTypeLED13 Sequence type for LED 13 LatchedAck-S-F -
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3.1.4 Time Synchronization
Guidelines for Settings:These settings are used for synchronizing IED clock time with network time. Ex: GPS or IRIG-B time.
CoarseSyncSrc: Select the time synchronization source available such as SPA, LON, SNTP etc.
Synchronization messages from sources configured as coarse are checked against the internal relay
time and only if the difference in relay time and source time is more than 10s then relay time will be
reset with the source time. This parameter need to be based on time source available in site.
FineSyncSource: Select the time source available in network like IRIG-B, GPS, SNTP, SPA etc.
once it is selected, time of available time source in network will update to relay if there is a difference
in the time between relay and source. This parameter need to be based on time source available in
site.
SyncMaster:Normally it is set OFF. If time to the relay is received from a GPS antenna (example),
make the relay as master to synchronize with other relays.
TimeAdjustRate:Fast
HWSyncSrc: This is applicable if process bus IEC61850-9-2 protocol is used for receiving analog
values (optical CT PTs). In this case select time source available same as that of merging unit. This
setting is not applicable in present case.
AppSynch: If there is any loss of time sync, protection function will be blocked if AppSynch set to
Synchbased on SyncAccLevel. If AppSunch set to NoSynch, protection functions are not blocked.Recommended setting is NoSynch.
SyncAccLevel: If this is set to Class T5 (1us) and time synch error is more than 1us, protection
functions will be blocked. SyncAccLevel should be set to Unspecified when Nosynch is selected at
AppSynch. This parameter is not applicable in present case.
ModulePosition: if BIN is set for FineSyncSource, ModulePosition setting is applicable. Here slot
position of IO module in the relay is to be set (Which slot is used for BI). This parameter is not
applicable in present case.
BinaryInput: Which binary input is used for time sync input shall be set here. This parameter is
applicable if BIN is set for FineSyncSource. This parameter is not applicable in present case.
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MonthInYear, DayInWeek, WeekInMonth and UTCTimeOfDay for DSTBEGIN and DSTEND are
applicable where Day light saving is used. If it is not used set same date for both DSTBEGIN and
DSTEND. This setting is not applicable in this case.
NoHalfHourUTC: Time shift from GMT has to be set a multiple of half hours. Example for India it is
+05:30, means +11. Hence this parameter is set to +11 in present case.
SYNCHIRIG-B Non group settings:These settings are applicable if IRIG-B is used. This parameter
is not applicable in present case.
SynchType:Type of hardware input used for time sync, whether Opto or BNC. This parameter is not
applicable in present case.
TimeDomain:In present case this parameter is set to LocalTime.
Encoding:In present case this parameter is set to IRIG-B.
TimeZoneAs1344:In present case this parameter is set to PlusTZ.
Recommended Settings:
Table 3-4 gives the recommended settings for Time synchonization.
Table 3-4: Time synchronization settings
TIMESYNCHGEN Non group settings (basic)
Setting
Parameter Description
Recommended
Settings Unit
CoarseSyncSrc Coarse time synchronization source Off -
FineSyncSource Fine time synchronization source 0.0 -
SyncMaster Activate IED as synchronization master Off -
TimeAdjustRate Adjust rate for time synchronization Off -
HWSyncSrc Hardware time synchronization source Off -
AppSynch Time synchronization mode for application NoSynch -
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SYNCHBIN Non group settings (basic)
SettingParameter Description
Recommended
Settings Unit
ModulePositionHardware position of IO module for time
Synchronization3 -
BinaryInputBinary input number for time
synchronization1 -
BinDetection Positive or negative edge detection PositiveEdge -
SYNCHSNTP Non group settings (basic)
Setting Parameter DescriptionRecommended
Settings Unit
ServerIP-Add Server IP-address 0.0.0.0 IP Address
RedServIP-Add Redundant server IP-address 0.0.0.0 IP Address
DSTBEGIN Non group settings (basic)
SettingParameter
Description RecommendedSettings Unit
MonthInYear Month in year when daylight time starts March -
DayInWeek Day in week when daylight time starts Sunday -
WeekInMonthWeek in month when daylight time
starts
Last -
UTCTimeOfDayUTC Time of day in seconds when
daylight time starts3600 s
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DSTEND Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
MonthInYear Month in year when daylight time starts October -
DayInWeek Day in week when daylight time starts Sunday -
WeekInMonth
Week in month when daylight time
starts Last -
UTCTimeOfDayUTC Time of day in seconds when
daylight time starts3600 s
TIMEZONE Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
NoHalfHourUTC Number of half-hours from UTC +11 -
SYNCHIRIG-B Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
SynchType Type of synchronization Opto -
TimeDomain Time domain LocalTime -
Encoding Type of encoding IRIG-B -
TimeZoneAs1344 Time zone as in 1344 standard PlusTZ -
Note: Above setting parameters have to be set based on available time source at site.
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t: The length of the pulse, sent out by the output signal SETCHGD when an active group has
changed, is set with the parameter t. This is not the delay for changing setting group. This parameter
is normally recommended to set 1s.
MAXSETGR:The parameter MAXSETGR defines the maximum number of setting groups in use to
switch between. Only the selected number of setting groups will be available in the Parameter
Setting tool (PST) for activation with the ActiveGroup function block. This parameter is normally
recommended to set 1.
Recommended Settings:
Table 3-5 gives the recommended settings for Parameter setting group.
Table 3-5: Parameter setting group
ActiveGroup Non group settings (basic)
SettingParameter
Description RecommendedSettings Unit
tPulse length of pulse when setting
Changed1 s
SETGRPS Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
ActiveSetGrp ActiveSettingGroup SettingGroup1 -
MAXSETGR Max number of setting groups 1-6 1 No
3.1.6 Test Mode Functionality TEST
Guidelines for Settings:
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Table 3-6 gives the recommended settings for Test mode functionality.
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Table 3-6: Test mode functionality
TESTMODE Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
TestMode Test mode in operation (On) or not (Off) Off -
EventDisable Event disable during testmode Off -
CmdTestBitCommand bit for test required or not
during testmodeOff -
3.1.7 IED Identifiers
Recommended Settings:
Table 3-7 gives the recommended settings for IED Identifiers.
Table 3-7: IED Identifiers
TERMINALID Non group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
StationName Station name Station-A -
StationNumber Station number 0 -
ObjectName Object name Line-1 -
ObjectNumber Object number 0 -
U itN U it REL670 M1
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3.1.8 Rated System Frequency PRIMVAL
Recommended Settings:
Table 3-8 gives the recommended settings for Rated system frequency.
Table 3-8: Rated system frequency
PRIMVAL Non group settings (basic)
SettingParameter
Description RecommendedSettings Unit
Frequency Rated system frequency 50.0 Hz
3.1.9 Signal Matrix For Analog Inputs SMAI
Guidelines for Settings:
DFTReference: Set ref for DFT filter adjustment here. These DFT reference block settings decide
DFT reference for DFT calculations.
The settings InternalDFTRef will use fixed DFT reference based on set system frequency.
AdDFTRefChn will use DFT reference from the selected group block, when own group selected
adaptive DFT reference will be used based on calculated signal frequency from own group. The
setting ExternalDFTRef will use reference based on what is connected to input DFTSPFC.
There are three different task groups of SMAI with 1ms, 3ms and 8ms. Use of each task group is
based on requirement of function, like differential protection requires 1ms, which is faster.
Each task group has 12 instances of SMAI, in that first instance has some additional features which
is called master. Others are slaves and they will follow master. If measured sample rate needs to be
transferred to other task group, it can be done only with master.
Receiving task group SMAI DFTreference shall be set to External DFT Ref.
DFTReference shall be set to default value InternalDFTRef if no VT input is available Since VT input
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connected to 3rdSMAI of 1ms task group, AdDFTRefCh3 is to be set in DFTRefExtOut of 1ms task
group.
DFTRefExtOut shall be set to default value InternalDFTRef if no VT input is available. Configuration
file has to be referred for this purpose.
Negation: Set negation of the function block here. If R, Y, B and N inputs are connected and
Negation is set to NegateN, it will give output R, Y, B and N. If Negation is set to Negate3Ph, it will
give output -R, -Y, -B and N.
If R, Y, B inputs are connected, N=R+Y+B, and it will do as above. This parameter is recommended
to be set to OFF normally.
MinValFreqMeas: Set the measured minimum value here. It is applicable only for voltage input.
SMAI will work only if measured input magnitude is greater than set value in MinValFreqMeas. This
parameter is recommended to set 10% normally.
UBase:Set the base voltage here. This is parameter is set to 400kV.
Recommended Settings:
Table 3-9 gives the recommended settings for Signal Matrix For Analog Inputs.
Table 3-9: Signal Matrix For Analog Inputs
SettingParameter
DescriptionRecommended
Settings Unit
DFTRefExtOut DFT reference for external output InternalDFTRef -
DFTReference DFT reference InternalDFTRef -
ConnectionType Input connection type Ph-Ph -
TYPE 1=Voltage, 2=Current1 or 2 based oninput
Ch
Negation Negation Off -
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3.1.10 General settings of Distance protection zones
Guidelines for Settings:
Figure 3-1 gives the setting angles for discrimination of forward and reverse fault.
ArgDir and ArgNegRes:Set the Directional angle Distance protection zones at ArgDir and set the
Negative restraint angle for Distance protection zone at ArgNegRes.
The setting of ArgDir and ArgNegRes is by default set to 15 (= -15) and 115respectively. It should
not be changed unless system studies have shown the necessity.
IBase:set to the current value of the primary winding of the CT. This parameter is set to 1000A in
present case.
UBase:set to the voltage value of the primary winding of the VT. This parameter is set to 400kV in
present case.
IMinOpPP:This is the minimum current required in phase to phase fault for directionality purpose.
To be set to 20% of IBase.
IMinOpPE:This is the minimum current required in phase to earth fault for directionality purpose.
To be set to 20% of IBase.
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Recommended Settings:Table 3-10 gives the recommended settings for General settings for distance protection.
Table 3-10: General settings for distance protection
ZDRDIR Group settings (basic)
SettingParameter
DescriptionRecommended
Settings Unit
IBase Base setting for current level 1000 A
UBase Base setting for voltage level 400 kV
IMinOpPPMinimum operate delta current forPhase-Phase loops
20 %IB
IMinOpPEMinimum operate phase current for
Phase-Earth loops20 %IB
ArgNegResAngle of blinder in second quadrant for
forward direction115 Deg
ArgDirAngle of blinder in fourth quadrant for
forward direction15 Deg
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3.1.11 Distance Protection Zone, Quadrilateral Characteristic (Zone 1)
ZMQPDIS
General guide lines for Setting Distance protection Zones:
The zones are set directly in primary ohms R, X. The primary ohms R, X are recalculated to
secondary ohms with the current and voltage transformer ratios. Figures 3-2 and 3-3 show the
characteristics for phase-to-earth measuring and phase-to-phase measuring respectively.
The secondary values are presented as information for zone testing.
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Figure 3-3: Characteristic for phase-to-phase measuring
Guidelines for Setting:
Zone-1:
Setting X1, R1 and X0, R0: To be set to cover 80% of protected line length. Zero sequence
compensation factor is (Z0 Z1) / 3Z1.
RFPP and RFPE: For phase to ground faults resistive reach should be set to give maximum
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In case of phase to phase fault, resistive reach should be set to provide coverage against all types
of anticipated phase to phase faults subject to check of possibility against load point encroachment
considering minimum expected voltage and maximum load expected during short time emergency
system condition.
To minimize the risk for overreaching, limit the setting of the zone 1 reach in resistive direction for
phase-to-phase loop measurement to:
RFPP 3 X1.
IBase:Set the Base current for the Distance protection zones in primary Ampere here. Set to thecurrent value of the primary winding of the CT. This parameter is set to 1000A in present case.
UBase: Set the Base voltage for the Distance protection zones in primary kV here. Set to the
voltage value of the primary winding of the VT. This parameter is set to 400kV in present case.
IMinOpPP:Setting of minimum sensitivity for zone Phase-Phase elements. Measures IL-IL for each
loop. This is the minimum current required in phase to phase fault for zone measurement. To be set
to 20% of IBase.
IMinOpPE: Setting of minimum operating current for Phase faults. Measures ILx. This is the
minimum current required in phase to earth fault for zone measurement. To be set to 20% of IBase.
IMinOpIN:This is the minimum 3I0current required in phase to earth fault for zone measurement.
To be set to 10% of IBase.
Setting Calculations:
OperationDir = Forward
Operation PP = On
Operation PE = On
Zone 1 phase fault reach is set to 80.0% of the total line reactance
X1Z1' = 46.664 Note! Zone will send carrier signal
The secondary setting will thus be
X1Z1 = 12.833
Set the positive sequence resistance for phase faults to (this gives the characteristic angle)
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The secondary setting will thus be
X0Z1 = 44.81
Set the zero sequence resistance for earth faults to
R0Z1' = 40.873
The secondary setting will thus be
R0Z1 = 11.24
Setting of the fault resistive cover
The resistive reach(phase to Phase) is set to cover a maximum expected fault resistance arrived
from Warrington formula given below
Rarc =
It is set to 15.0 . (Considering a minimum expected ph to ph fault current of 1500A and arc length
of 15meter).
Note that setting of fault resistance is the loop value whereas reactance setting is phase value forphase faults.
The resistive reach (phase to earth) is set as 50 keeping a value of 10 for tower footing
resistance, arc-resistance of 15and remote end infeed effect of 25(considering equal fault feed
from both side)
Set the resistive reach for phase faults to:
RFPPZ1' = 30(loop value)
The secondary setting will thus be
RFPPZ1 = 8.25
Set the resistive reach for earth faults to
RFPEZ1= 50
The secondary setting will thus be
RFPEZ1 = 13.75
Set the Base current for the Distance protection zones in primary Ampere.
Zone 1 setting of timers.
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Recommended Settings:
Table 3-11 gives the recommended settings for ZONE 1 Settings.
Table 3-11: ZONE 1 Settings
SettingParameter
DescriptionRecommended
Settings Unit
Operation Operation Off / On On -
IBase Base current , i.e rated current 1000 A
Ubase Base voltage , i.e.rated voltage 400.00 kV
OperationDir Operation mode of directionality Forward -
X1 Positive sequence reactance reach 46.664 ohm/p
R1 Positive sequence resistance reach 4.378 ohm/p
X0 Zero sequence reactance reach 162.944 ohm/p
R0 Zero sequence resistance for zone 40.873 ohm/p
RFPP Fault resistance reach in ohm/loop , Ph-Ph 30 ohm/l
RFPE Fault resistance reach in ohm/loop , Ph-E 50 ohm/l
OperationPP
Operation mode Off/On of Ph-Ph loops On -
Timer tPPOperation mode Off/On of Zone timer, Ph-Ph
On -
tPP Time delay of trip,Ph-Ph 0.000 s
OperationPE
Operation mode Off/On of Ph-E loops On -
Timer tPE Operation mode Off/On of Zone timer, Ph-E On -
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IMinOpINMinimum operate residual current forPhase-Earth loops
10 %IB
3.1.12 Distance Protection Zone, Quadrilateral Characteristic (Zone 2)
ZMQAPDIS
Guidelines for Setting:
Setting X1, R1 and X0, R0:
To be set to cover minimum 120% of length of principle line section. However, in case of double
circuit lines 150% coverage must be provided to take care of under reaching due to mutual coupling
effect. Zero sequence compensation factor is (Z0 Z1) / 3Z1.
tPP and tPE settings:
A Zone-2 timing of 0.35s (considering LBB time of 200mS, CB open time of 60ms, resetting time of
30ms and safety margin of 60ms) is set for the present case.
RFPP and RFPE:
Guidelines given for resistive reach under zone-1 is applicable here also. Due to in-feeds, the
apparent fault resistance seen by relay is several times the actual value. This should be kept inmind while arriving at resistive reach setting for Zone-2.
IBase:Set the Base current for the Distance protection zones in primary Ampere here. Set to the
current value of the primary winding of the CT. This parameter is set to 1000A in present case.
UBase: Set the Base voltage for the Distance protection zones in primary kV here. Set to the
voltage value of the primary winding of the VT. This parameter is set to 400kV in present case.
IMinOpPP:Setting of minimum sensitivity for zone Phase-Phase elements. Measures IL-IL for each
loop. This is the minimum current required in phase to phase fault for zone measurement. To be set
to 20% of IBase.
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Setting Calculations:
OperationDir = ForwardOperation PP = On
Operation PE = On
Zone 2 phase fault reach is set to 150.0%of the total line reactance
X1Z2' = 87.495 Zone is accelerated at receipt of Carrier signal.
The secondary setting will thus be
X1Z2 = 24.061
Set the positive sequence resistance for phase faults to (this gives the characteristic angle)
R1Z2' = 8.208
The secondary setting will thus be
R1Z2 = 2.257
Setting of zone earth fault zero sequence values
X0Z2' = 305.52 150.0%of the total line reactance
The secondary setting will thus be
X0Z2 = 84.018
Set the zero sequence resistance for earth faults to
R0Z2' = 76.637
The secondary setting will thus beR0Z2 = 21.075
Setting of the fault resistive cover
The resistive reach for phase to phase is set to cover a maximum expected fault resistance of
30.0
(Considering a factor of 2 on the Zone-1 resistive reach value to take care of in-feed effect)
Set the resistive reach for phase faults to:
RFPPZ2' = 60
The secondary setting will thus be
RFPPZ2 =16 5
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Zone 2 timers setting
Setting of Zone timer activation for phase-phase and earth faults
tPP2 = On
tPE2 = On
Setting of Zone timers:
tPP2 = 0.35s
tPE2 = 0.35s
Note: In this case, Zone-2 reach is not encroaching into 220kV side of the transformer due to in-
feeds and therefore zone-2 tripping delay need not be coordinated with HV side backup protection
of Transformer as explained in Appendix-I.
Recommended Settings:
Table 3-12 gives the recommended settings for ZONE 2 Settings.
Table 3-12: ZONE 2 Settings
SettingParameter
DescriptionRecommended
Settings Unit
Operation Operation Off / On On -
IBase Base current , i.e. rated current 1000 A
Ubase Base voltage , i.e. rated voltage 400.00 kV
OperationDir Operation mode of directionality Forward -
X1 Positive sequence reactance reach 87.495 ohm/p
R1 Positive sequence resistance reach 8.208 ohm/p
X0 Zero sequence reactance reach 305.52 ohm/p
R0 Zero sequence resistance for zone 76.637 ohm/p
RFPPFault resistance reach in ohm/loop Ph-
60 h /l
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SettingParameter
DescriptionRecommended
Settings Unit
tPP Time delay of trip,Ph-Ph 0.35 s
Operation PE Operation mode Off/On of Ph-E loops On -
Timer tPEOperation mode Off/On of Zone timer,Ph-E
On -
tPE Time delay of trip,Ph-E 0.35 s
IMinOpPPMinimum operate delta current for Phase-Phase loops
20 %IB
IMinOpPEMinimum operate phase current forPhase-Earth loops
20 %IB
3.1.13 Distance Protection Zone, Quadrilateral Characteristic (Zone 3)
ZMQAPDIS
Guidelines for Setting:
Setting X1, R1 and X0, R0: Zone-3 should overreach the remote terminal of the longest adjacent
line by an acceptable margin (typically 20% of highest impedance seen) for all fault conditions.
Zero sequence compensation factor is (Z0 Z1) / 3Z1.
tPP and tPE settings: Zone-3 timer should be set so as to provide discrimination with the
operating time of relays provided in subsequent sections with which Zone-3 reach of relay
being set, overlaps. In present case, Zone-3 time is set to 1.0s.
RFPP and RFPE: Guidelines given for resistive reach under zone-1 is applicable here also. Due to
in-feeds, the apparent fault resistance seen by relay is several times the actual value. This should
be kept in mind while arriving at resistive reach setting for Zone-3.
Model setting calculation document for Transmission Line
IMinOpPP: Setting of minimum sensitivity for zone Phase Phase elements Measures IL IL for each
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IMinOpPP:Setting of minimum sensitivity for zone Phase-Phase elements. Measures IL-IL for each
loop. This is the minimum current required in phase to phase fault for zone measurement. To be set
to 20% of IBase.IMinOpPE: Setting of minimum operating current for Phase faults. Measures ILx. This is the
minimum current required in phase to earth fault for zone measurement. To be set to 20% of IBase.
Setting Calculations:
OperationDir = Forward
Operation PP = On
Operation PE = On
Setting of zone 3 Phase fault reach
Zone 3 phase fault reach is set to 120% of sum of protected line and adjacent longest lines
reactance is considered. Effect of in-feed not considered for practical reasons in the Zone-3 reach
setting.X1Z3' = 199.304
The secondary setting will thus be
X1Z3 = 54.809
Set the positive sequence resistance for phase faults to (this gives the characteristic angle)
R1Z3' = 18.697
The secondary setting will thus be
R1Z3 = 5.142
Setting of zone earth fault zero sequence values
X0Z3' = 695.942 120% of sum of protected line and adjacent longest lines
reactance is considered.
The secondary setting will thus be
X0Z3 = 191.384
Set the zero sequence resistance for earth faults to
R0Z3' = 174.57
Model setting calculation document for Transmission Line
The faults on remote lines will have in-feed of fault current through the fault resistance from other
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The faults on remote lines will have in-feed of fault current through the fault resistance from other
remote feeders which will make an apparent increase of the value. The setting is selected to take
care of above factors. Set the resistive reach for phase faults to:RFPPZ3' = 75(Loop value)
The secondary setting will thus be
RFPPZ3 = 20.625
Set the resistive reach for earth faults to
RFPEZ3= 125
The secondary setting will thus be
RFPEZ3 = 34.375
Zone 3 timers setting
Setting of Zone timer activation for phase-phase and earth faults
tPP3 = On
tPE3 = On
Setting of Zone timers:
tPP3 = 1s
tPE3 = 1s
Note: In this case, Zone-3 reach is not encroaching into 220kV side of the transformer due to in-
feeds and therefore zone-3 tripping delay need not be coordinated with HV side backup protection
of Transformer as explained in Appendix-I.
Recommended Settings:
Table 3-13 gives the recommended settings for ZONE 3 Settings.
Table 3-13: ZONE 3 Settings
Setting
ParameterDescription
Recommended
Settings Unit
O ti O ti Off / O O
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Setting Recommended
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Setting
ParameterDescription
Recommended
Settings Unit
X0 Zero sequence reactance reach 695.942 ohm/p
R0 Zero sequence resistance for zone 174.57 ohm/p
RFPP Fault resistance reach in ohm/loop , Ph-Ph 75 ohm/l
RFPE Fault resistance reach in ohm/loop , Ph-E 125 ohm/l
Operation
PPOperation mode Off/On of Ph-Ph loops On -
Timer t1PP Operation mode Off/On of Zone timer, Ph-Ph On -
tPP Time delay of trip,Ph-Ph 1 s
Operation
PEOperation mode Off/On of Ph-E loops On -
Timer t1PE Operation mode Off/On of Zone timer, Ph-E On -
t1PE Time delay of trip,Ph-E 1 s
IMinOpPPMinimum operate delta current for Phase-
Phase loops20 %IB
IMinOpPEMinimum operate phase current for
Phase-Earth loops20 %IB
3.1.14 Distance Protection Zone, Quadrilateral Characteristic (Zone 5)
ZMQAPDIS
Guidelines for Setting:
Setting X1, R1 and X0, R0: Reverse reach setting shall be 50% of shortest line connected to the
local bus bar. Zero sequence compensation factor is (Z0 Z1) / 3Z1.
tPP and tPE settings: Zone-5 time delay would only need to co-ordinate with bus bar main
t ti f lt l d ith Z 1 f lt l f li t f th b t ti F
Model setting calculation document for Transmission Line
IBase:Set the Base current for the Distance protection zones in primary Ampere here. Set to the
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p p y p
current value of the primary winding of the CT. This parameter is set to 1000A in present case.
UBase: Set the Base voltage for the Distance protection zones in primary kV here. Set to thevoltage value of the primary winding of the VT. This parameter is set to 400kV in present case.
IMinOpPP:Setting of minimum sensitivity for zone Phase-Phase elements. Measures IL-IL for each
loop. This is the minimum current required in phase to phase fault for zone measurement. To be set
to 20% of IBase.
IMinOpPE: Setting of minimum operating current for Phase faults. Measures ILx. This is the
minimum current required in phase to earth fault for zone measurement. To be set to 20% of IBase.
Setting Calculations:
OperationDir = Reverse
Operation PP = On
Operation PE = On
Zone 5 phase fault reach is set to 50.0%of the shortest line reactance connected to the same bus.
X1Z5' = 6.14
The secondary setting will thus be
X1Z5 = 1.689
Set the positive sequence resistance for phase faults to (this gives the characteristic angle)
R1Z5' = 0.576
The secondary setting will thus be
R1Z5 = 0.158
Setting of zone earth fault zero sequence values
X0Z5' = 21.44
The secondary setting will thus beX0Z5 = 5.896
Set the zero sequence resistance for earth faults to
R0Z5' = 5.378
Model setting calculation document for Transmission Line
RFPPZ5 = 20.625
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Set the resistive reach for earth faults to
RFPEZ5= 125The secondary setting will thus be
RFPPZ5 = 34.375
Zone 5 (Reverse Zone) timers setting
Setting of Zone timer activation for phase-phase and earth faults
tPP5 = On
tPE5 = On
Setting of Zone timers:
tPP5 = 0.35s
tPE5 = 0.35s
Note: Time setting of this zone is not overlapping with zone-2 time of the adjacent shortest line on
the same bus.
Recommended Settings:
Table 3-14 gives the recommended settings for ZONE 5 Settings.
Table 3-14: ZONE 5 Settings
SettingParameter
DescriptionRecommended
Settings Unit
Operation Operation Off / On On -
IBase Base current , i.e. rated current 1000 A
Ubase Base voltage , i.e. rated voltage 400.00 kV
OperationDir Operation mode of directionality Reverse -
X1 Positive sequence reactance reach 6.14 ohm/p
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Setting Recommended
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SettingParameter
DescriptionRecommended
Settings Unit
RFPE Fault resistance reach in ohm/loop , Ph-E 125 ohm/l
OperationPP
Operation mode Off/On of Ph-Ph loops On -
Timer t1PP Operation mode Off/On of Zone timer, Ph-Ph On -
tPP Time delay of trip,Ph-Ph 0.35 s
OperationPE
Operation mode Off/On of Ph-E loops On -
Timer t1PE Operation mode Off/On of Zone timer, Ph-E On -
t1PE Time delay of trip,Ph-E 0.35 s
IMinOpPP Minimum operate delta current for Phase-Phase loops 20 %IB
IMinOpPEMinimum operate phase current for Phase-Earth loops
20 %IB
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3.1.15 Phase Selection with Load Encroachment, Quadrilateral Characteristic
FDPSPDIS
Figures 3-4, 3-5 and 3-6 show the characteristics for Phase selector and load encroachment:
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1-FDPSPDIS (red line), 2-ZMQPDIS, 3-0.5 x RFRvPP PHS, 4- X1PHS/ tan (60), 5-0.5 x
RFFwPPPHS, 6-0.5 x RFPPZm, 7-X1PHS, 8-X1Zm
Figure 3-5: Relation between distance protection (ZMQPDIS) and FDPSPDIS characteristicfor phase-to-phase fault for line>60
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RLdFw: Forward resistive reach within the load impedance areaRLdRv: Reverse resistive reach within the load impedance area
ArgLd: Load angle determining the load impedance reach
Figure 3-6: Load encroachment characteristic
Guidelines for Setting:
With the extended Zone-3 reach settings, that may be required to address the many under reaching
factors already considered, load impedance encroachment is a significant risk to long lines of an
interconnected power system. Not only the minimum load impedance under expected modes of
system operation be considered in risk assessment, but also the minimum impedance that might be
sustained for seconds or minutes during abnormal or emergency system conditions. Failure to do
so could jeopardize power system security.
For high resistive earth fault where impedance locus lies in the Blinder zone, fault clearance shall be
provided by the back-up directional earth fault relay.
IBase:Set the Base current for the Phase selection function in primary Ampere here. Set to the
current value of the primary winding of the CT. This parameter is set to 1000A in present case.
UBase:set to the voltage value of the primary winding of the VT. This parameter is set to 400kV in
present case
Model setting calculation document for Transmission Line
3I0 residual current must fulfill the conditions according to the equations given below
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3.I00.5 IMinOpPE
|3.I0| . Iphmax
where:
IMinOpPE is the minimum operation current for forward zones
Iphmax is the maximum phase current in any of three phases.
Conditions that have to be fulfilled in order to release the phase-to-phase loop are:
3I0< IMinOpPE
|3.I0| < . Iphmax
where:
IMinOpPE is the minimum operation current for earth measuring loops,
Iphmax is maximal magnitude of the phase currents.
Guidelines for Load encroachment:
The minimum load impedance can be calculated on the basis of maximum permitted power flow of
1500MVA over the protected line and minimum permitted system voltage. Minimum permitted system
voltage assumed is 360kV (90% of base voltage)
For setting angle for load blinder, a value of 30is set which is adequate.
Guidelines for Phase selection:Reactive reach
The reactive reach in forward direction must as minimum be set to cover the measuring zone used
in the Teleprotection schemes, mostly zone 2.
X1PHS1.44 X1Zm
X0PHS1.44 X0Zm
where:
X1Zm is the reactive reach for the zone to be covered by FDPSPDIS, and the constant 1.44 is a
safety margin
X0 is the zero sequence reactive reach for the zone to be covered by FDPSPDIS
Model setting calculation document for Transmission Line
where:
RFPE i h i RFPE f h l hi b d b FDPSPDIS
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RFPEZmis the setting RFPE for the longest overreaching zone to be covered by FDPSPDIS.
Phase-to-earth fault in reverse directionReactive reach
The reactive reach in reverse direction is the same as for forward so no additional setting is
required.
Resistive reach
The resistive reach in reverse direction must be set longer than the longest reverse zones. In
blocking schemes it must be set longer than the overreaching zone at remote end that is used in the
communication scheme.
RFRvPE 1.2 RFPE ZmRv
Phase-to-phase fault in forward direction
Reactive reach
The reach in reactive direction is determined by phase-to-earth reach setting X1.
No extra setting is required.
Resistive reach
In the same way as for phase-to-earth fault, the reach is automatically calculated based on setting
X1. The reach will be X1/tan(60) =X1/(3).
Fault resistance reach
The fault resistance reaches in forward direction RFFwPP, must cover RFPPZm with at least 25%margin. RFPPZm is the setting of fault resistance for phase to phase fault for the longest
overreaching zone to be covered by FDPSPDIS
RFFwPP 1.25 RFPPZm
where:
RFPPZmis the setting of the longest reach of the overreaching zones that must be covered by
FDPSPDIS .
RFRvPP 1.25 RFPPzmRv
The proposed margin of 25% will cater for the risk of cut off of the zone measuring characteristic
that might occur at three phase fault when FDPSPDIS characteristic angle is changed from 60to
Model setting calculation document for Transmission Line
IMinOpPE: Setting of minimum operating current for Phase faults. Measures ILx. This is the
i i t i d i h t th f lt f t T b t t 20% f IB
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minimum current required in phase to earth fault for zone measurement. To be set to 20% of IBase.
Setting Calculations:Calculations for Load encroachment:
Ur = 400kV, Umin = 0.90x400 = 360kV,
CT ratio = 1000/1A and PT ratio = 400kV/110V
Maximum load in MVA = 1500
ZLmin= 360 x 360/ (1500),
= 86.4
RLmin= 86.4 x cos30 = 74.82. Since considered load