Question 7: A 415V, three-phase, 50 Hz, 4-pole, star-connected induction motor runs at 24 rev/s on full load. The rotor resistance and reactance per phase are 0.35 ohm and 3.5 ohms, respectively. The effective rotor- stator turns ratio is 0.85:1. Calculate the synchronous speed, the slip, the full load torque, the power output if mechanical losses amount to 770W, the maximum torque, the speed at which maximum torque occurs, and the starting torque.

Question 7: A 415V, three-phase, 50 Hz, 4-pole, star-connected induction motor runs at 24 rev/s on full load. The rotor resistance and reactance per phase are 0.35 ohm and 3.5 ohms, respectively. The effective rotor- stator turns ratio is 0.85:1. Calculate the synchronous speed, the slip, the full load torque, the power output if mechanical losses amount to 770W, the maximum torque, the speed at which maximum torque occurs, and the starting torque.

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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