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A synchronous motor can be made self starting by providing
Answer & Solution
Correct Answer:
Option
A
To make a synchronous motor self-starting, a damper winding on the rotor poles is provided.
The damper winding consists of bars embedded in the rotor poles and short-circuited at both ends. When the motor is started, the relative motion between the rotating magnetic field of the stator and the rotor induces currents in the damper winding. These currents produce a magnetic field that interacts with the stator's magnetic field, generating torque and assisting in the motor's starting process.
Hence, option A is the correct choice.
The damper winding consists of bars embedded in the rotor poles and short-circuited at both ends. When the motor is started, the relative motion between the rotating magnetic field of the stator and the rotor induces currents in the damper winding. These currents produce a magnetic field that interacts with the stator's magnetic field, generating torque and assisting in the motor's starting process.
Hence, option A is the correct choice.
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LoginCorrect: A
Option: A
The synchronous motor is made self-starting by providing a special winding on the rotor poles, known as damper winding or squirrel cage winding. AC supply given to the stator produces a rotating magnetic field which causes the rotor to rotate. Therefore, in the beginning synchronous motor provided with damper winding starts as a squirrel cage induction motor. The exciter moves along the rotor. When the motor attains about 95%of synchronous speed, the rotor winding is connected to exciter terminals and the rotor is magnetically locked by the rotating field of the stator and the motor runs as a synchronous motor.