Question

A three-phase induction motor has rotor resistance per phase as 0.25Ω and maximum torque of 10Nm at 875 rpm. Motor has 6 poles with 50 Hz a fremuencv. Calculate motor torque at 5% slip.

Answer 1

The student's question requires using the torque-slip characteristics of an induction motor to calculate the torque at a specific slip value, given the motor's electrical and mechanical parameters.

Step-by-step explanation:

The question is about calculating the motor torque of a three-phase induction motor at a specific slip percentage.

The student provided the rotor resistance, maximum torque, speed at which maximum torque occurs, number of poles, and the frequency of the supply.

To calculate the torque at 5% slip, the torque-slip characteristics of the induction motor can be used, which typically state that torque is proportional to the slip at low values of slip.

Since the torque is maximum at the given speed, we need to calculate the slip at that speed first, and then use it to find the torque at 5% slip, given that the motor torque varies somewhat with the square of the slip.