Insertion of resistance in the rotor of an induction motor to develop a given torque?
Correct answer: D. rotor current rernains same
- A. decreases the rotor current
- B. increases the rotor current
- C. rotor current becomes zero
- D. rotor current rernains same
Explanation
For a specified torque, the required rotor current is essentially fixed; adding rotor resistance mainly increases slip and lowers the operating speed. This is the principle used for speed control in wound-rotor motors.
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