A 30 kV, 50 Hz, 50 MVA generator has the positive, negative, and zero sequence reactance’s of 0.25 pu, 0.15 pu, and 0.05 pu, respectively. The neutral of the generator is grounded with a reactance so that the fault current for a bolted LG fault and that of a bolted three-phase fault at the generator terminal are equal. The value of grounding reactance is:

A 30 kV, 50 Hz, 50 MVA generator has the positive, negative, and zero

1.	A 30 kV, 50 Hz, 50 MVA generator has the positive, negative, and zero sequence reactance’s of 0.25 pu, 0.15 pu, and 0.05 pu, respectively. The neutral of the generator is grounded with a reactance so that the fault current for a bolted LG fault and that of a bolted three-phase fault at the generator terminal are equal. The value of grounding reactance is:
A.	1 Ω
B.	1.8 Ω
C.	0.1 Ω
D.	2.18 Ω
Answer» C. 0.1 Ω

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