A 75kW, 440V, 3-phase, 6-pole,50Hz wound rotor induction motor has a full load slip of 0.04 and the slip at maximum torque of 0.2 when operating at rated voltage and frequency with rotor winding short circuited at the slip rings. Assume the stator resistance and rotational losses to be negligible. Find (a) Maximum torque (b) Starting torque (c) Full load copper loss. The rotor resistance is now doubled by adding an external series resistance.Determine (d) Slip at full load (e) full-load torque (f) slip at maximum torque

A 75kW, 440V, 3-phase, 6-pole,50Hz wound rotor induction motor has a full load slip of 0.04 and the slip at maximum torque of 0.2 when operating at rated voltage and frequency with rotor winding short circuited at the slip rings. Assume the stator resistance and rotational losses to be negligible. Find (a) Maximum torque (b) Starting torque (c) Full load copper loss. The rotor resistance is now doubled by adding an external series resistance.Determine (d) Slip at full load (e) full-load torque (f) slip at maximum torque

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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