A 440 V, 50 Hz, 4-pole, 3-phase, delta-connected motor has. a leakage impedance of (0.3 +j 5.5 +0.25/s) 2/phase (delta) referred to the stator. The stator to rotor voltage ratio is 2.5. Determine the external resistance to be inserted in each star phase of the rotor winding such that the motor develops a gross torque of 150 Nm at a speed of 1250 rpm.

A 440 V, 50 Hz, 4-pole, 3-phase, delta-connected motor has. a leakage impedance of (0.3 +j 5.5 +0.25/s) 2/phase (delta) referred to the stator. The stator to rotor voltage ratio is 2.5. Determine the external resistance to be inserted in each star phase of the rotor winding such that the motor develops a gross torque of 150 Nm at a speed of 1250 rpm.

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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