c) A 415V star-connected synchronous induction motor has a stator resistance of 0.5 ohms per phase and a combined rotor and exciter resistance of 2 ohms. On no- load and with unity power factor, the motor draws a line current of 5 amperes. If the excitation current is 10 amperes under no-load unity power factor conditions and 20 amperes under load condition, what is the efficiency of the motor when the line supply current is 100 amperes?

c) A 415V star-connected synchronous induction motor has a stator resistance of 0.5 ohms per phase and a combined rotor and exciter resistance of 2 ohms. On no- load and with unity power factor, the motor draws a line current of 5 amperes. If the excitation current is 10 amperes under no-load unity power factor conditions and 20 amperes under load condition, what is the efficiency of the motor when the line supply current is 100 amperes?

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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