The star-connected rotor of an induction motor has a standstill impedance of (0.4 + j4) ohm per phase and the rheostat impedance per phase is (6 + j2) ohm. The motor has induced emf of 80V between slip-rings at standstill when connected to its normal supply voltage. Find (a) rotor current at standstill with the rheostat in the circuit (b) when the slip-rings are shor circuited and the motor is running with a slip of 3%

The star-connected rotor of an induction motor has a standstill impedance of (0.4 + j4) ohm per phase and the rheostat impedance per phase is (6 + j2) ohm. The motor has induced emf of 80V between slip-rings at standstill when connected to its normal supply voltage. Find (a) rotor current at standstill with the rheostat in the circuit (b) when the slip-rings are shor circuited and the motor is running with a slip of 3%

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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