A three-phase, 60 Hz, squirrel-cage induction motor draws a current of 385 amps per phase and a total active power of 2344 kW when operating at full load from a 4000 volt (line) supply. The corresponding speed is 709.2 rev/min. The stator is star-connected and the resistance between two stator live terminals is 0.1 ohms. The machine has 10 poles, the total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate: (i) the power factor at full load? (ii) the active power supplied to the rotor? (iii) the total I'R losses in the rotor?

A three-phase, 60 Hz, squirrel-cage induction motor draws a current of 385 amps per phase and a total active power of 2344 kW when operating at full load from a 4000 volt (line) supply. The corresponding speed is 709.2 rev/min. The stator is star-connected and the resistance between two stator live terminals is 0.1 ohms. The machine has 10 poles, the total iron losses are 23.4 kW and the windage and friction losses are 12 kW. Calculate: (i) the power factor at full load? (ii) the active power supplied to the rotor? (iii) the total I'R losses in the rotor?

Electric Motor Control

10th Edition

ISBN:9781133702818

Author:Herman

Publisher:Herman

Chapter51: Electric And Electronic Braking

Section: Chapter Questions

Problem 2SQ: Differentiate between the AC and DC magnetic fields applied to an induction motor stator.

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