Technical reference manual RET 521*2.3 Transformer protection terminal

455 Pages·2001·6.36 MB·English

Technical reference manual
RET 521*2.3
Transformer protection terminal
Contents
Chapter Page
Functional description 3
Design description 267
References 303
Index 305
Customer feedback report 309
Example configurations 311
Service Notes 453
2
Functional description
The chapter “Functional description”.
This chapter describes the functions and logics within protection terminal RET 521.
The discription deals with how the functions are designed, how they operate, and their
signals and setting parameters. For hardware descriptions refer to the chapter “Design
descriptions”.
RET 521 terminal functionality............................................................................. 13
Terminal identification ........................................................................................13
General ......................................................................................................... 13
Terminal identification settings......................................................................14
Setting the terminal clock .............................................................................. 14
Displaying terminal identification numbers....................................................15
I/O module identification ...............................................................................15
User configurable module identification ........................................................16
Analog input data ............................................................................................... 16
Setting the phase reference channel ............................................................ 16
Configuration for analog inputs ..................................................................... 17
Setting of current channels ......................................................................18
Setting of voltage channels......................................................................19
Service value report ...................................................................................... 19
Power transformer data...................................................................................... 20
Basic transformer data..................................................................................20
Vector group setting strings ..................................................................... 21
Two winding transformer system .................................................................. 23
Three winding transformer systems..............................................................23
Activation of setting groups ................................................................................ 25
General ......................................................................................................... 25
Internal events....................................................................................................25
Using the built-in HMI.................................................................................... 26
Using front-connected PC or SMS................................................................28
Using SCS ....................................................................................................30
Time synchronization ......................................................................................... 30
System overview...........................................................................................30
Design........................................................................................................... 31
Configuration.................................................................................................31
Setting date and time .................................................................................... 33
Error signals.................................................................................................. 34
TIME-SYNCERR...................................................................................... 34
TIME-RTCERR ........................................................................................35
1MRK 504 016-UEN 3
Functional description
CAP 531 terminal diagram for Time function block.......................................36
CAP 531 signal lists for Time function block .................................................37
Setting table for time sources on built-in HMI ...............................................37
Restricted settings..............................................................................................37
General .........................................................................................................37
Installation and setting instructions ...............................................................38
Function block ...............................................................................................39
Inputs and outputs.........................................................................................39
Setting parameters and ranges.....................................................................40
Default configuration .....................................................................................40
Configuration overview.......................................................................................40
Description of configurations..............................................................................43
Configuration 1 (7I + 3U)...............................................................................43
Configuration 2 (2I + 8U)...............................................................................44
Configuration 3 (9I + 1U)...............................................................................44
Configuration No 4 (2x (7I + 3U)) ..................................................................45
Configuration No 5 ([8I+2U]&[9I+1U]) ...........................................................45
Configuration No 5a ([8I+2U]&[9I+1U]) .........................................................46
Configuration No 6 [9I+1U] ...........................................................................46
General functionality.............................................................................................47
Tripping logic (TR)..............................................................................................47
Summary of function .....................................................................................47
Description of logic........................................................................................47
Logic diagram................................................................................................48
Function block ...............................................................................................48
Input and output signals ................................................................................49
Setting parameters and ranges.....................................................................50
Terminal hardware structure (THWS) ................................................................50
Summary of application.................................................................................50
Summary of function .....................................................................................50
Description of logic........................................................................................50
Analogue input module (AIM) ..................................................................50
Binary input module (BIM) .......................................................................51
Binary output module (BOM) ...................................................................51
Input/output module (IOM) .......................................................................51
mA input module (MIM)............................................................................51
Terminal hardware structure (THWS) ......................................................51
Function block ...............................................................................................52
Analogue input module (AIM) ..................................................................52
Binary input module (BIM) .......................................................................55
Binary output module (BOM) ...................................................................56
4 1MRK 504 016-UEN
Functional description
Input/output module (IOM) .......................................................................57
mA input module (MIM)............................................................................58
Terminal HW structure (THWS) ............................................................... 59
Input and output signals................................................................................ 59
Setting parameters and ranges..................................................................... 61
Service report values .................................................................................... 62
Activation of setting groups (GRP)..................................................................... 65
Summary of function .....................................................................................65
Function block............................................................................................... 66
Input and output signals................................................................................ 66
Blocking during test (TEST) ...............................................................................66
Summary of function .....................................................................................66
Function block............................................................................................... 67
Input and output signals................................................................................ 67
No signal (NONE) ..............................................................................................67
Summary of function .....................................................................................67
Function block............................................................................................... 67
Input and output signals................................................................................ 68
Fixed signals (FIXD)...........................................................................................68
Summary of function .....................................................................................68
Function block............................................................................................... 68
Input and output signals................................................................................ 69
Fourier filter for single phase current (C1P) .......................................................69
Summary of function .....................................................................................69
Function block............................................................................................... 69
Input and output signals................................................................................ 70
Fourier filter for three phase current (C3P) ........................................................70
Summary of function .....................................................................................70
Function block............................................................................................... 70
Input and output signals................................................................................ 71
Sum function for three phase currents (C3C) ....................................................71
Summary of function .....................................................................................71
Function block............................................................................................... 72
Input and output signals................................................................................ 72
Fourier filter for single phase voltage (V1P).......................................................72
Summary of function .....................................................................................72
Function block............................................................................................... 73
Input and output signals................................................................................ 73
1MRK 504 016-UEN 5
Functional description
Fourier filter for three phase voltage (V3P) ........................................................73
Summary of function .....................................................................................73
Function block ...............................................................................................74
Input and output signals ................................................................................74
Binary converter (CNV) ......................................................................................74
Summary of function .....................................................................................74
Function block ...............................................................................................77
Input and output signals ................................................................................77
Setting parameters and ranges.....................................................................78
Configurable logic (CL) ......................................................................................78
Summary of application.................................................................................78
Summary of function .....................................................................................78
Description of logic........................................................................................78
General ....................................................................................................78
Inverter (INV) ...........................................................................................79
OR............................................................................................................79
AND .........................................................................................................80
Timer ........................................................................................................80
TimerLong................................................................................................81
Pulse ........................................................................................................81
Set-Reset with memory............................................................................82
MOVE ......................................................................................................82
Function block ...............................................................................................83
Input and output signals ................................................................................86
Setting parameters and ranges.....................................................................89
Command function (CM/CD)..............................................................................90
Summary of application.................................................................................90
Summary of function .....................................................................................90
Description of logic........................................................................................90
General ....................................................................................................90
Single Command function........................................................................91
Multiple Command function .....................................................................91
Communication between terminals ..........................................................91
Function block ...............................................................................................92
Input and output signals ................................................................................93
Setting parameters and ranges.....................................................................94
......................................................................................................................95
Protection functions .............................................................................................96
Frequency measurement function (FRME) ........................................................96
Summary of application.................................................................................96
Summary of function .....................................................................................97
Measuring principle .......................................................................................98
6 1MRK 504 016-UEN
Functional description
Logic diagram .............................................................................................104
Function block.............................................................................................105
....................................................................................................................105
Input and output signals..............................................................................105
Service report values ..................................................................................106
Differential protection (DIFP)............................................................................106
Summary of application ..............................................................................106
Summary of function ...................................................................................107
Measuring principles ...................................................................................109
Some definitions and requirements .......................................................109
Power transformer connection groups ...................................................110
Determination of differential (operate) currents .....................................111
Calculation of fundamental harmonic differential currents .....................111
Power transformer correction factors.....................................................114
Power transformers with On-Load Tap-Changer (OLTC) ......................115
T configuration (Circuit-breaker-and-a-half configuration) .....................116
Instantaneous differential currents.........................................................117
Differential currents due to factors other than faults ..............................117
Elimination of zero-sequence currents from differential currents...........118
Detection of inrush magnetizing currents...............................................121
Detection of inrush .................................................................................123
Detection of overexcitation magnetizing currents ..................................125
Determination of bias current.................................................................126
Determination of bias current in breaker-and-a-half schemes ...............127
Restrained differential protection: operate - bias characteristics ...........127
Unrestrained (instantaneous) differential protection ..............................130
Stability of differential protection against heavy external faults .............130
Transformer differential protection: a summary of principles .................132
Logic diagram ............................................................................................134
Function block.............................................................................................135
Input and output signals..............................................................................136
Setting parameters and ranges...................................................................137
Service value report ....................................................................................137
Three/phase time overcurrent protection (TOC) ..............................................138
Summary of application ..............................................................................138
Summary of function ...................................................................................138
Measuring principles ...................................................................................138
Time characteristics ...............................................................................138
Calculation of IEC inverse delays ..........................................................144
Directional control of overcurrent protection ..........................................145
Logic diagram .............................................................................................148
Function block.............................................................................................149
Input and output signals..............................................................................150
Setting parameters and ranges...................................................................151
Service report values ..................................................................................152
1MRK 504 016-UEN 7
Functional description
Restricted earth fault protection (REF).............................................................152
Summary of application...............................................................................152
Summary of function ...................................................................................153
Measuring principles ...................................................................................154
Fundamental principles of the restricted earth fault protection (REF)....154
REF as a Differential Protection.............................................................156
Calculation of Differential Current and Bias Current ..............................157
Detection of External Earth Faults .........................................................158
Algorithm of the restricted earth fault protection (REF) in short .............160
Logic diagram..............................................................................................161
Function block .............................................................................................161
Input and output signals ..............................................................................162
Setting parameter and ranges.....................................................................162
Service report values ..................................................................................162
Earth fault time-current protection (TEF)..........................................................163
Application of function .................................................................................163
Summary of function ...................................................................................164
Measuring principles ...................................................................................165
Non-directional earth fault protection .....................................................165
Logarithmic Curves ................................................................................171
Calculation of IEC inverse delays ..........................................................172
Directional control of the earth fault time current protection (TEF) ........173
Logic diagram..............................................................................................175
Function block .............................................................................................176
Input and output signals ..............................................................................178
Setting parameters and ranges...................................................................179
Service report values ..................................................................................180
Single/three-phase time overvoltage protection (TOV) ....................................180
Summary of application...............................................................................180
Summary of function ...................................................................................180
Measuring principles ...................................................................................181
General on TOV protection ....................................................................181
The three phase overvoltage protection ................................................182
The residual voltage protection..............................................................183
Single input overvoltage protection........................................................184
Logic diagrams...........................................................................................186
Function block .............................................................................................187
Input and output signals ..............................................................................189
Setting parameters and ranges...................................................................190
Service report values ..................................................................................190
Single/three-phase time undervoltage protection (TUV) ..................................190
Summary of application...............................................................................190
Summary of function ...................................................................................191
Measuring principles ...................................................................................191
8 1MRK 504 016-UEN
Functional description
General ..................................................................................................191
Application of function inputs .................................................................192
Application of function outputs ...............................................................192
Settings ..................................................................................................194
Application of TUV protection function service value.............................194
Function block.............................................................................................194
Input and output signals..............................................................................195
Setting parameters and ranges...................................................................196
Service report values ..................................................................................197
Thermal overload protection (THOL) ...............................................................197
Summary of application ..............................................................................197
Summary of function ...................................................................................198
Measuring principles ...................................................................................199
General ..................................................................................................199
Application of function outputs ...............................................................199
Function service values .........................................................................200
Application of function inputs .................................................................201
Application of inputs G3I and SIDE2W/SIDE3W ...................................202
Logic diagram .............................................................................................203
Function block.............................................................................................203
Input and output signals..............................................................................204
Setting parameters and ranges...................................................................205
Service report values ..................................................................................205
Overexcitation protection (V/Hz) (OVEX).........................................................206
Summary of function ...................................................................................206
Measuring principles ...................................................................................207
General ..................................................................................................207
OVEX variants .......................................................................................209
Operate time of the overexcitation protection. .......................................210
Cooling...................................................................................................214
OVEX protection function service report................................................214
Logic diagram .............................................................................................215
Function block.............................................................................................216
Input and output signals..............................................................................217
Setting parameters and ranges...................................................................218
Service report values ..................................................................................218
Voltage control (VCTR) ....................................................................................219
Summary of function ...................................................................................219
Measuring principles ...................................................................................219
VCTR Operation Mode (i.e. Control Location) .......................................219
Control Mode .........................................................................................219
Measured Quantities..............................................................................220
Voltage control for parallel transformers ................................................221
Manual Control of the parallel group (Adapt Mode) ...............................225
Logic diagram .............................................................................................227
1MRK 504 016-UEN 9