Toshiba GR200 Series Instruction Manual page 6

Contents
Introduction ......................................................................................................................................... 1
1
Protection functions ...................................................................................................................... 2
Purposes of the protection ..................................................................................................... 2
1.1.1
Requirements in the protection functions ............................................................................ 2
1.1.2
Behavior of backup protections ............................................................................................. 4
1.1.3
Concepts of current differential protection (DIF) function .................................................. 6
1.1.4
Concepts of distance protection (ZS/ZG) function ................................................................ 6
1.1.5
Concepts of carrier command protection (DISCAR/DEFCAR) function ........................... 10
1.1.6
Tripping CB by the protection functions .............................................................................. 10
1.1.7
Autoreclosing CB (ARC) after the operation of the protection functions ........................... 11
1.1.8
Conventional applications .................................................................................................... 11
1.1.9
Control......................................................................................................................................... 12
General control function ...................................................................................................... 12
1.2.1
Control and monitoring application .................................................................................... 12
1.2.2
Monitoring and metering functions ........................................................................................... 13
Hardware overview ..................................................................................................................... 14
Symbols used in logical diagrams .............................................................................................. 15
Abbreviation................................................................................................................................ 19
Function Block (FB), Function ID, Signal number (Data ID) .................................................. 21
Relay application ............................................................................................................................... 23
2
Current differential protection for the line ............................................................................... 24
Segregated-phase current differential protection function (DIFL) .......................................... 25
Differential protection characteristics (DIFL) ................................................................... 26
2.2.1
Check relays characteristics (OCs and UVs) ...................................................................... 32
2.2.2
CT circuit-failure detection (DIFL-CTF) ............................................................................ 34
2.2.3
Charging-current compensation (DIFL-Ic) ......................................................................... 35
2.2.4
Differential current monitor (DIFL-IDSV) ......................................................................... 37
2.2.5
Setting .................................................................................................................................. 38
2.2.6
Data ID ................................................................................................................................ 39
2.2.7
Zero-sequence current differential protection (DIFGL) ............................................................ 41
Differential protection characteristics (DIFGL) ................................................................. 41
2.3.1
Check relay characteristic (EFD)........................................................................................ 46
2.3.2
CT circuit-failure detection (DIFGL-CTF) ......................................................................... 47
2.3.3
Charging-current compensation (DIFGL-Ic) ...................................................................... 48
2.3.4
CT saturation countermeasure in DIFL (CTsat in DIFL) ........................................................ 49
Stabilization for CT saturation owing to through-fault current ....................................... 49
2.4.1
Settings against CT saturation ........................................................................................... 52
2.4.2
Setting .................................................................................................................................. 54
2.4.3
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6F2S1914 (0.49)