A 3-phase induction motor is driving a constant torque load at rated voltage and frequency. If both voltage and frequency are halved, following statements relate to the new condition if stator resistance, leakage reactance and core loss are ignored 

1. The difference between synchronous speed and actual speed remains same 2. The airgap flux remains same 3. The stator current remains same 4. The p.u. slip remains same Among the above, current statements are 

(A) All (B) 1, 2 and 3 (C) 2, 3 and 4 (D) 1 and 4

1 Answer

Answer :

A 3-phase induction motor is driving a constant torque load at rated voltage and frequency. If both voltage and frequency are halved, following statements relate to the new condition if stator resistance, leakage reactance and core loss are ignored 

1. The difference between synchronous speed and actual speed remains same 2. The airgap flux remains same 3. The stator current remains same 4. The p.u. slip remains same Among the above, current statements are 

(A) All (B) 1, 2 and 3 (C) 2, 3 and 4 (D) 1 and 4

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