The rotor resistance and standstill reactance of a 3-phase induction motor are respectively 0.015 2 and 0.09 $2 per phase. At normal voltage, the full-load slip is 3%. Estimate the percentage reduction in stator voltage to develop full-load torque at one-half of full-load speed. What is then the power [22.5%; 0.31 ] factor?

The rotor resistance and standstill reactance of a 3-phase induction motor are respectively 0.015 2 and 0.09 $2 per phase. At normal voltage, the full-load slip is 3%. Estimate the percentage reduction in stator voltage to develop full-load torque at one-half of full-load speed. What is then the power [22.5%; 0.31 ] factor?

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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