a) A 100 HP, 3 phase, 6 pole, 50 Hz induction motor has rotor impedance of (0.02+j0.15) per phase at standstill. Full load torque is obtained at 4 % slip. Calculate : (i) Full load speed (ii) Frequency of rotor current at full load. (iii) Speed at which maximum torque occurs. (iv) External resistance per phase to be inserted in the rotor circuit to get maximum torque at starting.

a) A 100 HP, 3 phase, 6 pole, 50 Hz induction motor has rotor impedance of (0.02+j0.15) per phase at standstill. Full load torque is obtained at 4 % slip. Calculate : (i) Full load speed (ii) Frequency of rotor current at full load. (iii) Speed at which maximum torque occurs. (iv) External resistance per phase to be inserted in the rotor circuit to get maximum torque at starting.

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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