A 460 V 25 Hp, 60 Hz, 4-pole, Y-connected induction motor has the following parameters in...

A 460 V 25 Hp, 60 Hz, 4-pole, Y-connected induction motor has the following parameters in ohms per phase referred to the stator circuit.

R₁= 0.641 W R₂= 0.332 W X₁= 1.106 W X₂=0.464 W X_m=26.3 W

The rotational losses are 1100 W and are assumed to be constant. The core loss is included in this figure. The motor is supplied at rated voltage and rated frequency. Calculate;

Synchronous speed
Slip at which maximum torque occurs
The maximum torque of the motor
Assuming that the torque curve is linear between T_max and synchronous speed, what is the motor mechanical torque at S_Tmax/2?

The supply frequency is reduced to 30 Hz.

What should be the supply voltage to keep the pole flux constant at 60 Hz value?
Repeat the solution for 30 Hz
Compare results of 30 Hz and 60 Hz operation.

Expert Solution

answer is attached..

Manojponduru answered 1 month ago

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