A 3-phase, 400 V, 6-pole, 3-phase, 50 Hz, star-connected synchronous motor has a resistance of 0.5 N and synchronous reactance of 4 2 per phase. It takes a current of 15 A at unity power factor when operating with a certain field current. If the load torque is increased until the line current is increased to 60 A, the field current remaining unchanged, calculate the torque developed and the new power factor.

A 3-phase, 400 V, 6-pole, 3-phase, 50 Hz, star-connected synchronous motor has a resistance of 0.5 N and synchronous reactance of 4 2 per phase. It takes a current of 15 A at unity power factor when operating with a certain field current. If the load torque is increased until the line current is increased to 60 A, the field current remaining unchanged, calculate the torque developed and the new power factor.

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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