In a three-phase induction motor__________?
Correct answer: B. power factor at starting is low as compared to that while running
- A. power factor at starting is high as compared to that while running
- B. power factor at starting is low as compared to that while running
- C. power factor at starting in the same as that while running
Explanation
At starting, rotor frequency is maximum and rotor leakage reactance is significant, so the motor draws a highly inductive current with low power factor. As the motor accelerates, rotor frequency and reactance fall, improving the power factor.
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