What are the advantages and dis-advantages of synchronous motor?

What are the advantages and dis-advantages of synchronous motor?
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1 Answer

Answer :

Advantages
a. It’s a constant speed motor and is equal to synchronous speed from no load to full load.
b. It has good efficiency higher than induction motor.
c. It can be run as a motor and also as an alternator as per the requirement. More over it can be used as synchronous condenser.

 Dis-advantages
a. It can not be used as a varying speed motor. Because its speed can not be varied.
b. As a motor it is not self-starting type and it can not be started on load.
c. It requires both AC and DC supply.
d. Hunting is also produced in this motor.
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