Consider a induction motor (slip-ring) having a three-phase star-connected rotor. When the stator is supplied with rated voltage, slip ring being open circuit, the induced emf value is 65 Volts. The value of 0.6 ohm and 5.5 ohm are the resistance and stand still reactance of rotor per phase. Determine the following: 1. Rotor current per phase when the rotor is at stand still and connected to rheostat of 5.5 ohm (star-connected) and reactance 0.6 ohm per phase. 2. Rotor current per phase when motor is running at slip of 4% while rheostat is short circuited.

Consider a induction motor (slip-ring) having a three-phase star-connected rotor. When the stator is supplied with rated voltage, slip ring being open circuit, the induced emf value is 65 Volts. The value of 0.6 ohm and 5.5 ohm are the resistance and stand still reactance of rotor per phase. Determine the following: 1. Rotor current per phase when the rotor is at stand still and connected to rheostat of 5.5 ohm (star-connected) and reactance 0.6 ohm per phase. 2. Rotor current per phase when motor is running at slip of 4% while rheostat is short circuited.

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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