Correct Answer - Option 3 : Zero torque
The damper winding consists of short-circuited copper bars embedded in the face of the rotor poles and short-circuited at both ends by heavy copper ring.
The function of damper winding in synchronous motor:
- As synchronous motor has no self-starting torque. Therefore, damper winding provides starting torque necessary for starting of the synchronous motor.
- It also prevents hunting of synchronous motor, that is it reduces oscillations of the rotor when the motor deviates from synchronism.
- The damping winding produces Zero torque when a synchronous motor is running at synchronous speed.
The function of damper winding in the synchronous generator:
- It is known that a synchronous generator is rotated by a prime mover providing it necessary starting torque.
Hence the only function of damper winding in the synchronous generator is:
- To prevent hunting of synchronous generator or to reduces oscillations of the rotor when the motor deviates from synchronism.
