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.

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 28RQ: What are the advantages and disadvantages of using the following types of motors? shaded-pole...

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