A 400 V, 5- Hz, 3-phase delta connected, 6-pole induction motor has following standstillleakage impedances per phase referred to stator:z1 = 1.2 + 2.1j ohm , Z2 =1.32 + 2.2j ohm.Neglecting magnetizing impedance, determine(a) gross output power at a slip of 0.04,(b) thechange in line current when the stator terminals are switched from star to delta at a slip of0.4,(c) the resistance to be added in each rotor phase to obtain a starting torque of 350 Nm

A 40 kW, 3-phse slip ring induction motor of negligible stator impedance runs at a speed0.96 times synchronous speed at rated torque. The slip at maximum torque is 4 times the fullload value. If the rotor resistance of the motor is is increased by 5 times, determine,(i) The speed, power output and rotor ohmic losses at rated torque(ii) The speed corresponding to maximum torque.Neglect mechanical losses.

10 kW, 6-pole, 50 Hz, 3- phase induction motor has linear torque-slip characteristicsbetween zero torque and maximum torque. The slip at which maximum torque of 520 Nmoccurs is 0.2. For mechanical losses of 600 W, find the speed at which motor would run whiledelivering rated shaft power.

A 3-phase, 1.5 kW, 415 V, 2-pole, 50 Hz, 2910 rpm induction motor delivers rated output power to a load. If the rotational loss is 150 W, determine the air-gap power.

A balanced star connected load of (2+j3) Ω per phase and a balanced delta-connected load of(6+j6) Ω per phase are connected in parallel to a three phase, 400V, 50Hz supply. Calculate thephase current in each load, the total current in each supply line, the total power supplied and theoverall power factor.

A 415-V, 50-Hz supply is applied to a three-phase star-connected balanced load. Each [10]phase has an impedance of R+jX ohms, where R=15 n and X = 13.4 n. Find the(i) phase voltage, f'2(ii) phase current,(iii) line current,(iv) power factor,(v) active power,(vi) reactive power,S,vii) total VA