The effect of stator slot and air gap length on High speed brushless PM motor

This paper describes the key issues of High-speed brushless PM motor design, such as rotor design, stator design, and determination of the main dimensions, and the overall design process was given. In this paper, a 2-pole 3-phase High-speed brushless PM motor with ratings of 7.5kW, 30,000rpm is designed, and the effect of the different air gap length and stator slot number on the motor performance was analyzed. The results show that larger number of stator slot decreases the rotor loss and the rotor torque ripple. Larger air gap length decreases the rotor loss.