(Solved): 1.1 A 4 pole-pairs induction motor, the supply frequency was 50Hz and the shaft speed was 735 ...

1.1 A 4 pole-pairs induction motor, the supply frequency was $50\mathrm{Hz}$ and the shaft speed was $735\mathrm{rpm}$. What were the magnitudes of the following: 1.1.1. The synchronous speed 1.1.2. The speed of slip and the per unit slip 1.1.3. The frequency of the rotor current when the slip is $3\%$ 1.2 Some $1100\mathrm{V},50\mathrm{Hz}$, delta connected induction motor has a star connected slip-ring rotor with a stator to rotor ratio of 3.8. The rotor resistance and standstill leakage reactance are $0.012\Omega$ and $0.25\Omega$ per phase respectively. Neglecting stator impedance and magnetizing current, determine: 1.2.1 The rotor current at start with slip-ring shorted (4) 1.2.2 The rotor power factor at start with slip-rings shorted 1.2.3 The rotor current at $4\%$ slip with slip-rings shorted (3) 1.2.4 The external rotor resistance per phase required to obtain a starting current of $100\mathrm{A}$ in the stator supply lines. (5) 1.3 State four quantities that could be found when performing a blocked rotor test. (4) [25]