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Problem: 1. 1100v, 50Hz,delta connected induction motor has a star connected slip ring rotor with stator to stator transformation ratio of 3.8 . the rotor resistance and stand still reactance are 0.012 ohm and 0.25 ohm. Neglecting stator impedance and magnetizing current determine:
i. Rotor current and power factor at start with slip rings shorted. ii. Rotor current and power factor at 4% slip with slip rings shorted. iii. External rotor resistance per phase to obtain a starting current of 100A in stator supply lines.