The stator resistance, stator-referred rotor resistance and equivalent inductive reactance of a 400 V, 4-pole, 50 Hz, Y-connected induction motor are 0.22 Q, 0.25 Q and 3.5 Q, respectively. The motor is driving a constant load torque of 45 Nm at 1410 RPM. Calculate the motor speed and starting current if the supply frequency is reduced to 42 Hz. Compare and comment on the starting currents before and after the frequency is reduced. Assume that the rotational losses are negligible.

The stator resistance, stator-referred rotor resistance and equivalent inductive reactance of a 400 V, 4-pole, 50 Hz, Y-connected induction motor are 0.22 Q, 0.25 Q and 3.5 Q, respectively. The motor is driving a constant load torque of 45 Nm at 1410 RPM. Calculate the motor speed and starting current if the supply frequency is reduced to 42 Hz. Compare and comment on the starting currents before and after the frequency is reduced. Assume that the rotational losses are negligible.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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