A 440 V, dc shunt motor has a rated armature current of 76 A at a speed of 1000 rev/min. The armature resistance of the motor is 0.377 0, the field resistance is 1100, and the rotational losses are 1 kW. The load torque of the motor is bidirectional. Calculate the following: (a) No-load speed of the motor (b) Motor speed, where the armature current is 60 A during regenerative braking (c) Motor torque during regenerative braking

A 440 V, dc shunt motor has a rated armature current of 76 A at a speed of 1000 rev/min. The armature resistance of the motor is 0.377 0, the field resistance is 1100, and the rotational losses are 1 kW. The load torque of the motor is bidirectional. Calculate the following: (a) No-load speed of the motor (b) Motor speed, where the armature current is 60 A during regenerative braking (c) Motor torque during regenerative braking

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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