What is induction motor repulsion?
“The Repulsion Start Induction motor comprises a wound field or stator of laminated structure and a wound armature or rotor whose coils are connected to a commutator upon which brushes bear and function during the starting period. … Consequently this type of motor is regarded as having a high efficiency at start.
At what speed commutation of a repulsion motor is best?
The commutation of the motor is good at all speeds. No-load speed is above synchronous speed but normal speed is somewhat below synchronous one.
Why compensating winding is used in a repulsion motor?
It is a modified form of the straight repulsion motor discussed above. It has an additional stator winding, called compensating winding whose purpose is (i) to improve power-factor and (ii) to provide better speed regulation.
What are the demerits of repulsion motor?
Disadvantages of Repulsion Motor :
- Maintenance required for commutator is more.
- Chances of sparking at the brushes.
- Replusion motors are more expensive.
- It is not a constant speed motor and speed decreases with an increase in load.
- The operation of repulsion is noisy.
Which of the following is an advantage of a repulsion motor?
The advantage of repulsion motors is that the rotational speed can be varied within wide limits without the use of auxiliary apparatus. The motors have the disadvantage of being complicated in structure. Repulsion motors are used in low-power variable-speed single-phase AC drives.