GE Multilin
T60 Transformer Protection System
9-11
9 COMMISSIONING
9.2 DIFFERENTIAL CHARACTERISTIC TEST EXAMPLES
9
9.2.5 TEST EXAMPLE 4
D/D0° TRANSFORMER WITH PHASE B TO C FAULT ON THE SECONDARY DELTA WINDING.
Transformer: D/D0°, 20 MVA, 115/12.47 kv, CT1 (200:1), CT2 (1000:1)
Figure 9–5: CURRENT DISTRIBUTION OF D/D TRANSFORMER WITH AN a TO b FAULT ON THE LV SIDE
TEST
PHASE
INJECTED CURRENT
DISPLAYED CURRENT
STATUS
W1 CURRENT
W2 CURRENT
DIFFERENTIAL
RESTRAINT
Balanced
Condition
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Not Applicable
B
0.435
∠
–90°
0.8
∠
–270°
0
∠
0°
0.8
∠
–270°
C
0.435
∠
–270°
0.8
∠
–90°
0
∠
0°
0.8
∠
–90°
Min Pickup
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Block
I
d
= 0.065 < Min PKP
B
0.09
∠
–90°
0.23
∠
–270°
0.065
∠
0°
0.230
∠
–270°
C
0.09
∠
–270°
0.23
∠
–90°
0.065
∠
0°
0.230
∠
–90°
Min Pickup
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Operate
I
d
= 0.101 > Min PKP
B
0.21
∠
–90°
0.486
∠
–270°
0.102
∠
0°
0.486
∠
–270°
C
0.21
∠
–270°
0.486
∠
–90°
0.101
∠
0°
0.486
∠
–90°
Slope 1
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Block
I
d
/
I
r
= 14% < 15%
B
0.651
∠
–90°
1.39
∠
–270°
0.195
∠
0°
1.39
∠
–270°
C
0.651
∠
–270°
1.39
∠
–90°
0.195
∠
0°
1.39
∠
–90°
Slope 1
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Operate
I
d
/
I
r
= 16.8% > 15%
B
0.63
∠
–90°
1.39
∠
–270°
0.233
∠
0°
1.39
∠
–270°
C
0.63
∠
–270°
1.39
∠
–90°
0.233
∠
0°
1.39
∠
–90°
Intermediate
Slope 1 & 2
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Block
I
d
/
I
r
= 52.6%
< 60% computed
B
1.2
∠
–90°
4.63
∠
–270°
2.44
∠
–270°
4.63
∠
–270°
C
1.2
∠
–270°
4.63
∠
–90°
2.44
∠
–90°
4.63
∠
–90°
Intermediate
Slope 1 & 2
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Operate
I
d
/
I
r
= 68.8%
> 60% computed
B
0.8
∠
–90°
4.63
∠
–270°
3.18
∠
–270°
4.63
∠
–270°
C
0.8
∠
–270°
4.63
∠
–90°
3.18
∠
–90°
4.63
∠
–90°
Slope 2
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Block
I
d
/
I
r
= 93.2%
< Slope 2 = 95%
B
0.315
∠
–90°
8.33
∠
–270°
7.77
∠
–270°
8.33
∠
–270°
C
0.315
∠
–270°
8.33
∠
–90°
7.77
∠
–90°
8.33
∠
–90°
Slope 2
A
0
∠
0°
0
∠
0°
0
∠
0°
0
∠
0°
Operate
I
d
/
I
r
= 96%
> Slope 2 = 95%
B
0.18
∠
–90°
8.33
∠
–270°
8
∠
–270°
8.33
∠
–270°
C
0.18
∠
–270°
8.33
∠
–90°
8
∠
–90°
8.33
∠
–90°
828739A1.CDR
D/d
0
° Transformer
F
I (f) = 0
A
I (f) = 0.866 pu
–90°
b
∠
I (f) = 0
a
I (f) = 0.866 pu
–270°
c
∠
I (f) = 0.866 pu
–90°
B
∠
I (f) = 0.866 pu
–270°.
C
∠
A
B
C
A
B
C
H
w
inding
X
w
inding
Summary of Contents for UR T60
Page 10: ...x T60 Transformer Protection System GE Multilin TABLE OF CONTENTS ...
Page 14: ...xiv T60 Transformer Protection System GE Multilin 0 1 BATTERY DISPOSAL 0 BATTERY DISPOSAL 0 ...
Page 34: ...1 20 T60 Transformer Protection System GE Multilin 1 5 USING THE RELAY 1 GETTING STARTED 1 ...
Page 436: ...5 298 T60 Transformer Protection System GE Multilin 5 10 TESTING 5 SETTINGS 5 ...
Page 678: ...C 30 T60 Transformer Protection System GE Multilin C 7 LOGICAL NODES APPENDIX C C ...
Page 688: ...D 10 T60 Transformer Protection System GE Multilin D 1 IEC 60870 5 104 PROTOCOL APPENDIX D D ...
Page 700: ...E 12 T60 Transformer Protection System GE Multilin E 2 DNP POINT LISTS APPENDIX E E ...