Correct option is D
A change in supply frequency is not a cause of hunting in a synchronous motor:
- Hunting
The phenomenon of a synchronous motor's rotor oscillating around its synchronous speed due to load variations. Hunting can be caused by a number of factors, including:
- Sudden changes in load
- Faults in the generator's supply system
- Sudden changes in field current
- Cyclic variations of load torque
- Power supply disturbances, such as voltage dips or surges
- Damper winding
Prevents hunting by dampening out oscillations. It also provides starting torque, making the motor self-starting.
- Effects of hunting
Can lead to loss of synchronism, instability, energy losses, reduced efficiency, and challenges in controlling the motor's speed.
