Example 9.22 The resistance and standstill reactance of each phase of a 3-phase induction motor with star-connected rotor are 0-06 2 and 0-4 2 respectively. The full-load slip is 4%. Calculate the resistance per phase of a star-connected rheostat which when connected to the rotor circuit will give a pull-out torque at one half of the full-load speed. What is then the power factor?

Example 9.22 The resistance and standstill reactance of each phase of a 3-phase induction motor with star-connected rotor are 0-06 2 and 0-4 2 respectively. The full-load slip is 4%. Calculate the resistance per phase of a star-connected rheostat which when connected to the rotor circuit will give a pull-out torque at one half of the full-load speed. What is then the power 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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Question

Example 9.22 The resistance and standstill reactance of each phase of a 3-phase induction
motor with star-connected rotor are 0-06 2 and 0-4 2 respectively. The full-load slip is 4%. Calculate
the resistance per phase of a star-connected rheostat which when connected to the rotor circuit will
give a pull-out torque at one half of the full-load speed. What is then the power factor?
A

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