Semi-closed slots or totally closed slots are used in induction motors to improve
Semi-closed slots or totally closed slots are used in induction motors to improve Power Factor.
The purpose of closed slots in an induction motor is to reduce the air gap between the stator and rotor, which reduces the amount of flux leakage and increases the magnetic coupling between the stator and rotor.
This results in a higher power factor, improved efficiency, and reduced losses.
Totally closed slots provide the best performance in terms of power factor improvement.
In this design, the slots are completely filled with magnetic material, which eliminates the slot opening altogether.
This results in a higher magnetic coupling and a significant reduction in flux leakage. As a result, totally closed slots help to improve the power factor and efficiency of the motor.