A star connected 400V, 50Hz, 4 pole synchronous machine gave the following open circuit and short circuit test results : Open circuit test : Voc = 400 V (rms, line-to-line) at field current, If = 2.3 A Short circuit test : Isc = 10 A (rms, phase) at field current, If = 1.5 A The value of per phase synchronous impedance in &ohm; at rated voltage is _____________

A star connected 400V, 50Hz, 4 pole synchronous machine gave the follo

1.	A star connected 400V, 50Hz, 4 pole synchronous machine gave the following open circuit and short circuit test results : Open circuit test : V_oc = 400 V (rms, line-to-line) at field current, I_f = 2.3 A Short circuit test : I_sc = 10 A (rms, phase) at field current, I_f = 1.5 A The value of per phase synchronous impedance in Ω at rated voltage is _____________
A.	156
B.	15.06
C.	16
D.	5.06
Answer» C. 16

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