The synchronous motor is not inherently self-starting because_______________?
Correct answer: A. the force required to accelerate the rotor to the synchronous speed in an instant is absent
- A. the force required to accelerate the rotor to the synchronous speed in an instant is absent
- B. the starting device to accelerate the rotor to near synchronous speed is absent
- C. a rotating magnetic field does not have enough poles
- D. the rotating magnetic field is produced by only 50 Hz frequency currents
Explanation
At standstill, the stator’s rotating field produces torque that reverses rapidly relative to the stationary rotor, giving no average starting torque. The rotor would need to be accelerated near synchronous speed before it could lock into synchronism.
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