Question

Why is the air gap between stator and rotor should be kept as small as mechanically possible in induction motor?

(a) to reduce the leakage flux between stator and rotor

(b) as it leads to better operating power factor of the induction motor

(c) reduce the eddy current losses

(d) both, to reduce leakage flux between stator and rotor, and also for better operating power factor

This question was posed to me by my school principal while I was bunking the class.

My question is based upon Constructional Features of Rotating Electrical Machines-1 topic in section Constructional Features of Rotating Electrical Machines of Electrical Machines

Answer 1

Correct option is (d) both, to reduce leakage flux between stator and rotor, and also for better operating power factor

To explain I would say: The leakage flux and power factor depend on the air gap and it should be as small as possible.