Investigation and Design of a High-Power Flux-Switching Permanent Magnet Machine for Hybrid Electric Vehicles

Flux-switching permanent magnet (FSPM) machines exhibit high torque density, high efficiency, and robust rotor structure. In this paper, a prototype of a high-power three-phase 12-stator-slot/10-rotor-pole FSPM motor used for hybrid electric vehicles (HEVs) is designed by finite-element analysis (FEA). First, the initial FEA model is improved by gradually taking into account lamination B-H curves due to different electrical frequencies, operation temperatures, 3-D end effect, and rotor eccentric. Thereafter, a modular manufacture method of the FSPM motor is discussed with the improved FEA model and validated by experimental measurements. Then, the measured overload capability of the FSPM motor is compared with that of an interior permanent magnet (IPM) motor used in Honda Civic, and the results indicate that the IPM motor exhibits significantly stronger overload capability, which is analyzed in depth from soft-iron materials, cooling conditions, and and so on. Finally, both the merits and demerits of FSPM motor employed for low-voltage and high-current HEV applications are highlighted.