Investigation and comparison of the flux-switching permanent magnet machine and FSCW surface-mounted permanent magnet machine with close pole-pair number

The very close d-axis and q-axis inductances of the flux-switching permanent magnet (FSPM) machine make it even similar to a surface-mounted permanent magnet (SPM) machine, especially those with fractional slot and concentrated windings (FSCW), which is usually applied in a light-power situation where small size and high power density are desired. Based on finite element analysis (FEA), the FSPM machine with 6-slots/5-poles (5 pole pairs) is designed for light servo applications and further compared to an SPM machine with 9-slots/8-poles (4 pole pairs), covering electromagnetic, thermal, and mechanical behaviors. The rotor skewing of the FSPM machine is also studied. Finally, the prototypes of the FSPM and SPM machines are manufactured and experimental measurements are carried out to validate the FEA results.