Question

In: Electrical Engineering

A 400 V dc shunt motor has a rated armature current of 76 A at a...

A 400 V dc shunt motor has a rated armature current of 76 A at a speed of 1000 rpm. The armature resistance of the motor is 0.4ohm, the field resistance is 100 ohm, and the rotational losses are 0.9 kW. The load of the motor is bidirectional. Calculate the following:

(a) No-load speed of the motor.

(b) Motor speed, where the armature current is 60 A during regenerative braking.

(c) Developed torque during regenerative braking.

(d) Back electromotive force, ea during regenerative braking.

(e) Power delivered by the source under normal motor operation.

(f) Terminal current under regenerative braking.

(g) Generated power during regenerative braking.

h) Total losses under regenerative braking.

(i) Power delivered to the source under regenerative braking.

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