2. APPLICATION
2-6
DTP-B Digital Transformer Protection
GEK-106243E
2.3 TRANSFORMER CALCULATIONS (FIGURE 6)
2.3.1 1
ST
ITERATION. CALCULATIONS REFERRED TO THE TRANSFORMER SHOWN IN FIGURE 6
2.3.1.1 Matching Error
1. Transformer
winding
A B C
2. Ipmax=5000/
√
3x
(kV-LL)
21.9
43.8
87.6
3. 100%Ip = 4000/
√
3
x
(kV-LL)
17.5
35
70
4.
Current
CT
Ratio
20
20
40
5. Isec max (less than 5 A)
1.10
2.19
2.19
6.
100%
Isec
0.87
1.75
1.75
7.
CT
Connections
wye
wye
wye
8. Relay currents for 100% Isec
0.87
1.75
1.75
Select a relay tap for one of the windings (A, B, or C) and calculate the ideal relay taps for the other windings
using:
Relay current in next winding
Ideal tap=
x selected relay tap
Relay current in selected winding
9. Ideal relay taps (select A= 2.5):
2.5
5.03
5.03
Select the closest available tap to the ideal taps
10. Actual relay taps (In=5)
2.5
5.0
5.0
(0.5xIn)
(1.0xIn)
(1.0xIn)
Содержание DTP-B
Страница 23: ...3 OPERATING PRINCIPLES 3 6 DTP B Digital Transformer Protection GEK 106243E ...
Страница 53: ...10 INSTALLATION AND MAINTENANCE 10 2 DTP B Digital Transformer Protection GEK 106243E ...
Страница 66: ...12 FIGURES GEK 106243E DTP Digital Transformer Protection 12 1 12 FIGURES Figure 1 External Connections ...
Страница 67: ...12 FIGURES 12 2 DTP B Digital Transformer Protection GEK 106243E Figure 2 Panel Drilling Dimensions ...
Страница 68: ...12 FIGURES GEK 106243E DTP Digital Transformer Protection 12 3 Figure 3 RS 232 Connection ...
Страница 69: ...12 FIGURES 12 4 DTP B Digital Transformer Protection GEK 106243E Figure 4 Dimensions Diagram ...
Страница 70: ...12 FIGURES GEK 106243E DTP Digital Transformer Protection 12 5 Figure 5 Front View ...
Страница 73: ...12 FIGURES 89 DTP B Digital Transformer Protection GEK 106243E Figure 8 Block Diagram of the Protection ...