Question

In the rotor voltage injection method, when an external voltage source is in phase with the main voltage then speed will

• A. Decrease
• B. First increases then decrease
• C. Increase
• D. Remain unchanged

Hint:

In rotor voltage injection, in-phase voltage injection increases the motor speed by reducing the slip.

Answer 1

The Correct Option is C

In the rotor voltage injection method, when the external voltage source is in phase with the main voltage, the speed of the motor will increase because the phase difference between the stator and rotor is reduced, allowing more effective torque production. Thus, the correct answer is Increase.