A 3-phase 440V, wye connected induction motor has a star-connected stator and delta connected rotor with a turns ratio of 10. The rotor resistance and standstill reactance per phase are 0.01Ω and 0.2Ω respectively, what should be the value of external resistance (in Ω) that must be inserted to the rotor circuit in order to obtain maximum torque at starting?

A 3-phase 440V, wye connected induction motor has a star-connected stator and delta connected rotor with a turns ratio of 10. The rotor resistance and standstill reactance per phase are 0.01Ω and 0.2Ω respectively, what should be the value of external resistance (in Ω) that must be inserted to the rotor circuit in order to obtain maximum torque at starting?

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter39: Synchronous Motor Operation

Section: Chapter Questions

Problem 14SQ: Induction motors and welding transformers require magnetizing current, which causes a. lagging power...

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