GE UR Series Instruction Manual page 9

8. THEORY OF OPERATION
9. APPLICATION OF
SETTINGS
GE Power Management
TABLE OF CONTENTS
7.2 TARGETS
7.2.1 TARGETS MENU............................................................................................... 7-3
7.2.2 RELAY SELF-TESTS......................................................................................... 7-3
8.1 OVERVIEW
8.1.1 INTRODUCTION................................................................................................ 8-1
8.1.2 ARCHITECTURE ............................................................................................... 8-1
8.1.3 REMOVAL OF DECAYING OFFSET................................................................. 8-2
8.1.4 PHASELET COMPUTATION ............................................................................. 8-2
8.1.5 ADAPTIVE STRATEGY ..................................................................................... 8-3
8.1.6 DISTURBANCE DETECTION............................................................................ 8-3
8.1.7 FAULT DETECTION .......................................................................................... 8-3
8.1.8 CLOCK SYNCHRONIZATION ........................................................................... 8-5
8.1.9 FREQUENCY TRACKING AND PHASE LOCKING .......................................... 8-6
8.1.10 FREQUENCY DETECTION ............................................................................... 8-6
8.1.11 PHASE DETECTION ......................................................................................... 8-7
8.1.12 PHASE LOCKING FILTER .............................................................................. 8-10
8.1.13 CLOCK IMPLEMENTATION ............................................................................ 8-12
8.1.14 MATCHING PHASELETS ................................................................................ 8-12
8.1.15 START-UP ....................................................................................................... 8-13
8.1.16 HARDWARE AND COMMUNICATION REQUIREMENTS ............................. 8-13
8.1.17 ON-LINE ESTIMATE OF MEASUREMENT ERRORS .................................... 8-13
8.1.18 CT SATURATION DETECTION ...................................................................... 8-14
8.1.19 CHARGING CURRENT COMPENSATION ..................................................... 8-14
8.1.20 DIFFERENTIAL ELEMENT CHARACTERISTICS........................................... 8-16
8.1.21 RELAY SYNCHRONIZATION.......................................................................... 8-16
8.2 OPERATING CONDITION CALCULATIONS
8.2.1 DEFINITIONS .................................................................................................. 8-18
8.2.2 2 TERMINAL MODE ........................................................................................ 8-18
8.2.3 TRIP DECISION EXAMPLE............................................................................. 8-22
8.2.4 TRIP DECISION TEST .................................................................................... 8-22
9.1 L90 CT REQUIREMENTS
9.1.1 INTRODUCTION................................................................................................ 9-1
9.1.2 CALCULATION EXAMPLE 1 ............................................................................. 9-1
9.1.3 CALCULATION EXAMPLE 2 ............................................................................. 9-2
9.2 CURRENT DIFFERENTIAL (87L) SETTINGS
9.2.1 INTRODUCTION................................................................................................ 9-3
9.2.2 CURRENT DIFF PICKUP .................................................................................. 9-3
9.2.3 CURRENT DIFF RESTRAINT 1 ........................................................................ 9-3
9.2.4 CURRENT DIFF RESTRAINT 2 ........................................................................ 9-3
9.2.5 CURRENT DIFF BREAK PT .............................................................................. 9-3
9.2.6 CT TAP .............................................................................................................. 9-4
9.3 DISTANCE BACKUP/SUPERVISION
9.3.1 DESCRIPTION................................................................................................... 9-5
9.3.2 PHASE DISTANCE ............................................................................................ 9-6
9.3.3 GROUND DISTANCE ........................................................................................ 9-6
9.4 POTT SIGNALING SCHEME
9.4.1 DESCRIPTION................................................................................................... 9-7
9.5 SERIES COMPENSATED LINES
9.5.1 DISTANCE SETTINGS ON SERIES COMPENSATED LINES ......................... 9-8
9.6 LINES WITH TAPPED TRANSFORMERS
9.6.1 DESCRIPTION................................................................................................... 9-9
9.6.2 TRANSFORMER LOAD CURRENTS................................................................ 9-9
9.6.3 FAULTS AT THE LV SIDE OF THE TRANSFORMER(S) ............................... 9-10
9.6.4 EXTERNAL GROUND FAULTS ...................................................................... 9-10
L90 Line Differential Relay v