A 3-phase transmission line operates at 33 kV. It has a resistance of 5 Ω and reactance of 15 Ω. It is connected to a busbar of an alternator through a 5 MVA step up transformer which has a reactance of 0.05 pu. Two alternators rated 10 MVA, XS = 0.08 pu and 5 MVA, XS = 0.06 pu are connected to busbars. A fault between phases at HV terminals of the transformer occurs. The MVA of the fault will be

A 3-phase transmission line operates at 33 kV. It has a resistance of

1.	A 3-phase transmission line operates at 33 kV. It has a resistance of 5 Ω and reactance of 15 Ω. It is connected to a busbar of an alternator through a 5 MVA step up transformer which has a reactance of 0.05 pu. Two alternators rated 10 MVA, XS = 0.08 pu and 5 MVA, XS = 0.06 pu are connected to busbars. A fault between phases at HV terminals of the transformer occurs. The MVA of the fault will be
A.	34.6
B.	67.6
C.	81.2
D.	91.5
Answer» C. 81.2

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