Q.3 (Part 1: 14 marks) A three phase 4XY V, 50 Hz 6-pole induction motor has per phase rotor winding turns as half of the per phase stator winding turns. The following parameters were determined from stator and rotor separately (independently), by using LCR meter directly: Stator: Series resistance: 0.10 Q *Series reactance: 0.25 Q *Mag. Reactance: 12 Q Rotor: *Resistance: 0.03 Q *Reactance: 0.07 Q If the rotational losses in the machine are 350 W and the motor runs at 4% slip, determine/answer the following (Do not use any assumptions!): a. Motor speed in rad/sec (1 marks) b. Current drawn by the motor from grid (3 marks) c. Stator cu losses (1 mark) d. Airgap power (1 mark) e. Induced torque and shaft torque (1 marks) f. Motor efficiency (1 mark) g. Starting torque (2 marks) h. How much will be the speed of the motor at pullout torque? (2 marks) i.How much should be the actual rotor resistance in order to make the pullout torque at start?(2 marks)

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