Design of IPMSM to Reduce Cogging Torque Considering Tapping the Rotor and Shape of Barrier

Generally, cogging torque derives from motor using permanent magnet such as interior permanent magnet synchronous motor (IPMSM) and surface permanent magent synchronous motor (SPMSM). The cogging torque works for smoothness in rotation of the rotor, but it is a kind of root cause mechanical vibration and acoustic noise. Consequently, cogging torque must be reduced by all manner of means. There are various methods to reduce the cogging torque, but this paper deals with two ways in the IPMSM. One is tapping the rotor and the other is design of barrier shape. Besides, this paper proposes best design of the IPMSM to reduce cogging torque, and the analysis of cogging torque by using FEM is compared with experimental results to verify.