engineering recuitment HPCL Engineer Mock Test 2024 Power Systems Protective Relays Differential Relays
Consider a stator winding of an alternator with an internal high – resistance ground fault. The currents under the fault condition are as shown in the figure. The winding is protected using a differential current scheme with current transformers of ratio 400 / 5 A as shown. The current through the operating coils is
1
0.1875 A
2
0.2 A
3
0.375 A
4
60 kA