In a synchronous motor, the magnitude of stator back e.m.f. & depends on_______________?
Correct answer: A. d.c. excitation only
- A. d.c. excitation only
- B. speed of the motor
- C. load on the motor
- D. both the speed and rotor flux
Explanation
At constant supply frequency, synchronous speed is fixed, so the stator back-emf magnitude is controlled mainly by the rotor's DC excitation. Increasing field current increases rotor flux and hence the induced back emf.
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