A Design Method for Cage Induction Motors With Non-Skewed Rotor Bars

To overcome the influence of the skewed rotor bars on the operating performance of the cage induction motors, this paper presents a design method for non-skewed small and medium cage induction motor based on the time-stepping finite element method, in which the approaches of asymmetrical rotor slots, closed slots, reasonable slot combination, and air-gap length are adopted and studied systematically. With this method, the cage induction motors with non-skewed rotor bars can be realized. Simultaneously, the slot harmonic, which is caused by slot opening, can be eliminated effectively and the starting performance can also be improved. The design example on a 5.5 kW cage induction motor is presented and the experimental validation is also performed.