By which of the following methods the constant speed of a synchronous motor can be changed to new fixed value ?
Correct answer: A. By changing the supply frequency
- A. By changing the supply frequency
- B. By interchanging any two phases
- C. By changing the applied voltage
- D. By changing the loadLearn Quantum Physics
Explanation
A synchronous motor runs at Ns = 120f/P, so changing the supply frequency changes its fixed speed. Voltage and load changes affect torque and current, not the synchronous speed.
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