GE T60 User Manual

GE Multilin T60 Transformer Protection System 8-9
8 COMMISSIONING 8.2 DIFFERENTIAL CHARACTERISTIC TEST EXAMPLES
8
8.2.3 TEST EXAMPLE 2
D/YG30° TRANSFORMER WITH PHASE A TO GROUND FAULT ON THE GROUNDED WYE.
Transformer: D/y30°, 20 MVA, 115/12.47 kv, CT1 (200:1), CT2 (1000:1)
Figure 8–3: CURRENT DISTRIBUTION ON A D/YG30° TRANSFORMER WITH A LV-SIDE GROUND FAULT
TEST PHASE INJECTED CURRENT DISPLAYED CURRENT STATUS
W1 CURRENT W2 CURRENT DIFFERENTIAL RESTRAINT
Balanced
Condition
A 0.29 0° 0.926 –180° 0 0° 0.5349 –180° Not Applicable
B0 0° 0 0° 0 0° 0 0°
C 0.29 –180° 0 0° 0 0° 0.5349 0°
Minimum
Pickup
A 0.137 0° 0.521 –180° 0.048 0° 0.3 –180° Block
I
d
= 0.048 < Min PKP
B0 0° 0 0° 0 0° 0 0°
C 0.137 –180° 0 0° 0.048 0° 0.3 0°
Minimum
Pickup
A 0.108 0° 0.521 –180° 0.102 0° 0.3 –180° Operate
I
d
= 0.102 > Min PKP
B0 0° 0 0° 0 0° 0 0°
C 0.108 –180° 0 0° 0.102 0° 0.3 0°
Slope 1 A 0.4435 0° 1.6 –180° 0.110 0° 0.9026 –180° Block
I
d
/I
r
= 11.9%
B0 0° 0 0° 0 0° 0 0°
C 0.4435 –180° 0 0° 0 0° 0 0°
Slope 1 A 0.4425 0° 1.7 –180° 0.165 0° 0.979 –180° Operate
I
d
/I
r
= 16.8%
B0 0° 0 0° 0 0° 0 0°
C 0.4425 –180° 0 0° 0.165 0° 0.979 0°
Intermediate
Slope 1 & 2
A1.2 0° 5 –180° 0.675 –180° 2.882 –180° Block
I
d
/I
r
= 23.4%
B0 0° 0 0° 0 0° 0 0°
C1.2 –180° 0 0° 0.675 0° 2.882 0°
Intermediate
Slope 1 & 2
A1.1 0° 5 –180° 0.860 –180° 2.882 –180° Operate
I
d
/I
r
= 29.8%
B0 0° 0 0° 0 0° 0 0°
C1.1 –180° 0 0° 0.860 0° 2.882 0°
Slope 2 A 0.4 0° 15 –180° 7.915 –180° 8.646 –180° Block
I
d
/I
r
= 91.5%
B0 0° 0 0° 0 0° 0 0°
C0.4 –180° 0 0° 7.915 0° 8.646 0°
Slope 2 A 0.2 0° 15 –180° 7.918 –180° 8.650 –180° Operate
I
d
/I
r
= 95.7%
B0 0° 0 0° 0 0° 0 0°
C0.2 –180° 0 0° 7.916 0° 8.650 0°
828737A1.CDR
D/y30° Transformer
Fault
I (f) = 0.577 pu 0°
A
∠
I(f)=0
b
I(f)=1pu 0°
a
∠
I(f)=0
c
I(f)=0pu
B
I (f) = 0.577 pu –180°
C
∠
A
B
C
A
B
C

GE T60 Specifications

General

Brand	GE
Model	T60
Category	Relays
Language	English