A 4-pole, 50 hz, 3-phase induction motor has a slip-ring rotor with resistance and standstill reactance of 0.04 ohm and 0.2 ohm per phase respectively. Find the amount of resistance to be inserted in each rotor phase to obtain full-load torque at starting. What will be the approximate power factor in the rotor at this instant? The slip at full-load is 3 percent.

A 4-pole, 50 hz, 3-phase induction motor has a slip-ring rotor with resistance and standstill reactance of 0.04 ohm and 0.2 ohm per phase respectively. Find the amount of resistance to be inserted in each rotor phase to obtain full-load torque at starting. What will be the approximate power factor in the rotor at this instant? The slip at full-load is 3 percent.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter35: Harmonics 916

Section: Chapter Questions

Problem 3RQ: Would a positive-rotating harmonic or a negative-rotating harmonic be more harmful to an induction...

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