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Q4. A 100 kW. Three-phase induction motor runs on a 6600 V supply. Synchronous speed is 500 rev/min, motor slip and power factor at full load are 1.8 % and 0.85 lagging respectively, and the losses are as follows:

i) Stator copper losses 2.44 kW

ii) Stator iron losses 3.5 kW

iii) Rotational losses 1.2 kW

(a) Calculate EACH of the following:

(i) The rotor copper loss; (4)

(ii) The line current; (4)

(iii) The efficiency; (2)

(b) Sketch a labelled power-flow diagram for the motor indicating power at each stage. (6)