A 3-phase, 4-pol, 50-Hz induction motor has a star-connected rotor. The voltage of each rotor phase at standstill and on open-circuit is 121 V. The rotor resistance per phase is 0.3 Ω and the reactance at standstill is 0.8 Ω. If the rotor current is 15A, calculate the speed at which the motor is running. Also, Calculate the speed at which the torque is a maximum and the corresponding value of the input power to the motor, assuming the flux to remain constant.

A 3-phase, 4-pol, 50-Hz induction motor has a star-connected rotor. The voltage of each rotor phase at standstill and on open-circuit is 121 V. The rotor resistance per phase is 0.3 Ω and the reactance at standstill is 0.8 Ω. If the rotor current is 15A, calculate the speed at which the motor is running. Also, Calculate the speed at which the torque is a maximum and the corresponding value of the input power to the motor, assuming the flux to remain constant.

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 13RQ: A squirrel-cage induction motor is operating at 1175 RPM and producing a torque of 22 Ib-ft. What is...

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