Analysis and Comparison of Axial Field Flux-Switching Permanent Magnet Machines With Three Different Stator Cores

Axial field flux-switching permanent magnet machine (AFFSPMM) is a novel brushless AC machine, which incorporates the advantages of flux-switching permanent magnet machine and axial field permanent magnet machine. It is suitable to be applied in the field of direct drive electric vehicles due to short axial size and large torque density. In the paper, the different stator core structures such as U-, C-, and E-shape are researched on basis of a three-phase 600 W conventional AFFSPMM. These parameters including rotor pole numbers, stator tooth shape, and the deflection angle of rotor pole are optimized for obtaining sinusoidal back electromotive force and small cogging torque. The electromagnetic performances are analyzed and compared by 3-D finite element method. It is found that C-core AFFSPMM can get higher output torque in comparison with U-core machine, and E-core machine can improve fault-tolerant capability and reduce the torque ripple.