A synchronous motor is operating on no-load at unity power factor. If the field current is increased, power factor will become (A) Leading & current will decrease (B) Lagging & current will increase. (C) Lagging & current will decrease. (D) Leading & current will increase.

A synchronous motor is operating on no-load at unity power factor. If the field
 current is increased, power factor will become
(A) Leading & current will decrease
(B) Lagging & current will increase.
(C) Lagging & current will decrease.
(D) Leading & current will increase.
by

1 Answer

Answer :

Ans: A
Initially synchronous motor is operating at no load and unity power factor. When
field current increases, the excitation will increase. Therefore, p.f will be leading and
current will be I CosΦ < I
by

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