1. What is the difference between ac induction motor
and ac synchronous motor?

Answer Posted / tajmera

1. Synchronous motor is not self starting, but induction
motor is self starting.
2. In synchronous motor, a d.c. supply is required for rotor
excitation. But in induction motor, d.c. supply is not required.
3.By adjusting the d.c. field excitation of synchronous
motor, it can be made to operate from lagging to leading
p.f. But 3-phase induction motor always operates at low
lagging p.f.
4. Synchronous motor can be used for variable speed
operations because it runs at synchronous(or one) speed at
all loads. But induction motor can be used for variable
speed operations because it's speed vary with the loads.
5. Synchronous motor requires high cost as compared to
induction motor.

Is This Answer Correct ?    4 Yes 2 No



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