A 460-V, 25-hp, 60-Hz, four pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R, = 0.641N R2 = 0.332N X1 = 1.106N The total rotational losses are 1100 W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 2.2 % at the rated voltage and rated frequency, find the motor's a) Speed X2 = 0.4640 Хм — 26.30 d) Pcony and Pout b) Stator current e) Tind and Tioad c) Power factor f) Efficiency

A 460-V, 25-hp, 60-Hz, four pole, Y-connected induction motor has the following impedances in ohms per phase referred to the stator circuit: R, = 0.641N R2 = 0.332N X1 = 1.106N The total rotational losses are 1100 W and are assumed to be constant. The core loss is lumped in with the rotational losses. For a rotor slip of 2.2 % at the rated voltage and rated frequency, find the motor's a) Speed X2 = 0.4640 Хм — 26.30 d) Pcony and Pout b) Stator current e) Tind and Tioad c) Power factor f) Efficiency

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.3P

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