Reduction of Vibration on Concentrated Winding Permanent Magnet Synchronous Motors with Considering Radial Stress

Abstract

Concentrated winding motors have a tendency to increase its vibration, and the vibration is bigger than distributed winding motors. This phenomenon is caused by tugging force between two neighboring teeth. Accordingly, we tried to reduce the vibration with considering radial stress of the motor. In this paper, it is shown that radial stress becomes partly big, and it makes excitation of stator core in natural mode of radial vibration. Therefore, air gap length where radial force is big should be enlarged. Furthermore, we found that radial stress in air gap becomes smoothly by enlarging air gap partly, and we can reduce the vibration the motors without decreasing its efficiency.