The resistance and standstill reactance of each phase of a 3-phase induction motor with star- connected rotor are 0.062 and 0.42 respectively. The full-load slip is 4%. Calculate the resistance per phase of a star-connected rheostat which when connected to the rotor will give a pull out torque at one-half of full-load speed. What is then power factor? Ans[0.1482, 0.707Lag]

The resistance and standstill reactance of each phase of a 3-phase induction motor with star- connected rotor are 0.062 and 0.42 respectively. The full-load slip is 4%. Calculate the resistance per phase of a star-connected rheostat which when connected to the rotor will give a pull out torque at one-half of full-load speed. What is then power factor? Ans[0.1482, 0.707Lag]

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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