A 460V, 25hp, 60Hz, 4 pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R1 = 0.641 Ω R2 = 0.332 Ω X1 = 1.106 Ω X2 = 0.436 Ω Xm = 26.3 Ω The total rotational losses are 1100W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 3.5% at the rated voltage and rated frequency, find the motor’s Speed Stator current Power factor Pconv and Pout Ʈǐnd and Ʈload Efficiency

A 460V, 25hp, 60Hz, 4 pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R1 = 0.641 Ω R2 = 0.332 Ω X1 = 1.106 Ω X2 = 0.436 Ω Xm = 26.3 Ω The total rotational losses are 1100W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 3.5% at the rated voltage and rated frequency, find the motor’s Speed Stator current Power factor Pconv and Pout Ʈǐnd and Ʈload Efficiency

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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