5.a) A 4 pole, 3 phase induction motor operates from a 50 Hz supply. Calculate (a) Speed at which the magnetic field of the stator is rotating (b) Speed of the rotor when the slip is 0.04 (c) Frequency of the rotor current when the slip is 0.03 (d) Frequency of the rotor current at standstill 5.b) The power input to a 500 V, 50 Hz, 6 pole, 3 phase induction motor running at 975 rpm is 40 KW. The stator losses are 1 KW and the friction and windage losses total 2 KW. Calculate: (i) Slip (ii) Rotor copper loss (iii) Shaft power and (iv) Efficiency

5.a) A 4 pole, 3 phase induction motor operates from a 50 Hz supply. Calculate (a) Speed at which the magnetic field of the stator is rotating (b) Speed of the rotor when the slip is 0.04 (c) Frequency of the rotor current when the slip is 0.03 (d) Frequency of the rotor current at standstill 5.b) The power input to a 500 V, 50 Hz, 6 pole, 3 phase induction motor running at 975 rpm is 40 KW. The stator losses are 1 KW and the friction and windage losses total 2 KW. Calculate: (i) Slip (ii) Rotor copper loss (iii) Shaft power and (iv) Efficiency

Electricity for Refrigeration, Heating, and Air Conditioning (MindTap Course List)

10th Edition

ISBN:9781337399128

Author:Russell E. Smith

Publisher:Russell E. Smith

Chapter8: Basic Electric Motors

Section: Chapter Questions

Problem 17RQ

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