Improve cogging torque method in inset-permanent magnet synchronous machine

This paper dealt with the investigation of the cogging torque reduction method in Inset-Permanent Magnet Synchronous Machine. In the study, fractional and integral slot number of permanent magnet synchronous machines have been compared. Cogging torque has been analyzed to be reduced by slot opening width, slotting of permanent magnet edges and also the combination of slot opening width reduced and shaping of permanent magnet edges. Electromagnetic simulations and analysis of the Inset-PMSM in this paper were performed by using a-2D finite element (FEMM 4.2). It is shown that by combining of reduced slot opening width and shaping of permanent magnet edges of the Inset-Permanent Magnet Synchronous Machine (Inset-PMSM) can reduce the cogging torque effectively. The cogging torque of both fractional and integral slot number can be reduced more than 97 % compared with original magnet structure. The flux density in the core of the permanent magnet synchronous machine also decreased.