A three phase, 60 Hz, 6-poles induction motor has a full-load speed of at 1150 rpm and delivers constant torque. If we reduce the speed of this motor to 960 rpm with adding external resistance to its rotor circuit, what would be the ratio of rotor losses at this speed to rotor losses at full-load speed?

A three phase, 60 Hz, 6-poles induction motor has a full-load speed of at 1150 rpm and delivers constant torque. If we reduce the speed of this motor to 960 rpm with adding external resistance to its rotor circuit, what would be the ratio of rotor losses at this speed to rotor losses at full-load speed?

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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