Download  Print this page

GE UR Series Instruction Manual Page 157

Line differential relay.
Hide thumbs
   
1
2
3
4
Table of Contents
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470

Advertisement

5 SETTINGS
5.5 GROUPED ELEMENTS
The Power Swing Detect element provides both power swing blocking and out-of-step tripping functions. The element mea-
sures the positive-sequence apparent impedance and traces its locus with respect to either two or three user-selectable
operating characteristic boundaries as per user choice. Upon detecting appropriate timing relations, the blocking and/or
tripping indication is given through FlexLogic™ operands. The POWER SWING OPERATING CHARACTERISTICS and
POWER SWING LOGIC figures should be viewed along with the following discussion to develop an understanding of the
operation of the element.
a) POWER SWING BLOCKING
Three-step operation:
The power swing blocking sequence essentially times the passage of the locus of the positive-sequence impedance
between the outer and the middle characteristic boundaries. If the locus enters the outer characteristic (as indicated by set-
ting of the POWER SWING OUTER FlexLogic™ operand) but stays outside the middle characteristic (as indicated by set-
ting of the POWER SWING MIDDLE FlexLogic™ operand) for an interval longer than
the
POWER SWING PICKUP DELAY 1
power swing blocking signal (POWER SWING BLOCK FlexLogic™ operand) is established and sealed-in. The blocking
signal resets when the locus leaves the outer characteristic, but not sooner than after
time.
POWER SWING RESET DELAY 1
Two-step operation:
If the 2-step mode is selected, the sequence is identical, but it is the outer and inner characteristics that are used to time the
power swing locus.
b) OUT-OF-STEP TRIPPING
Three-step operation:
The out-of-step trip sequence identifies unstable power swings by determining if the impedance locus spends a finite time
between the outer and middle characteristics and then a finite time between the middle and inner characteristics.
5
The first step is similar to the power swing blocking sequence. After timer
times out, Latch 1
POWER SWING PICKUP DELAY 1
is set as long as the impedance stays within the outer characteristic.
If afterwards, at any time (given the impedance stays within the outer characteristic), the locus enters the middle character-
istic but stays outside the inner characteristic for a period of time defined as
, Latch 2 is set as
POWER SWING PICKUP DELAY 2
long as the impedance stays inside the outer characteristic.
If afterwards, at any time (given the impedance stays within the outer characteristic), the locus enters the inner characteris-
tic and stays there for a period of time defined as
, Latch 2 is set as long as the impedance
POWER SWING PICKUP DELAY 3
stays inside the outer characteristic - the element is now ready to trip.
If the "Early" trip mode is selected, operand POWER SWING TRIP is set immediately and is sealed-in for the interval estab-
lished by setting
.
POWER SWING SEAL-IN DELAY
If the "Delayed" trip mode is selected, the element waits until the impedance locus leaves the inner characteristic, then
times out the
delay, and sets Latch 4 - the element is now ready to trip. The trip operand will
POWER SWING PICKUP DELAY 2
be set later, when the impedance locus leaves the outer characteristic.
Two-step operation:
The 2-step mode of operation is similar to the 3-step mode with two exceptions. First, the initial stage monitors the time
spent by the impedance locus between the outer and inner characteristics. Second, the stage involving timer POWER
SWING PICKUP DELAY 2 is bypassed.
It is up to the user to integrate the blocking (POWER SWING BLOCK) and tripping (POWER SWING TRIP) FlexLogic™
operands with other protection functions and output contacts in order to make this element fully operational.
GE Power Management
L90 Line Differential Relay
5-73

Advertisement

Table of Contents

   Also See for GE UR Series

   Related Manuals for GE UR Series

This manual is also suitable for:

L90

Comments to this Manuals

Symbols: 0
Latest comments: