- Three phase induction motor has rating of 50 kW, 960 rpm, 400 V. 50 Hz, 6-pole. The motor parameters are R = 0.08 , R = 0.1 , X = X = 0.3 2 and the moment of inertia 10 kg- m². It is required to stop the motor from its no load speed under reverse breaking operation. Find the required value of external resistance that need to put in rotor circuit such way that breaking will be achieved with minimum time. What is breaking time.

- Three phase induction motor has rating of 50 kW, 960 rpm, 400 V. 50 Hz, 6-pole. The motor parameters are R = 0.08 , R = 0.1 , X = X = 0.3 2 and the moment of inertia 10 kg- m². It is required to stop the motor from its no load speed under reverse breaking operation. Find the required value of external resistance that need to put in rotor circuit such way that breaking will be achieved with minimum time. What is breaking time.

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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