A new general design method of segmented-rotor wound field flux-switching motors with complementary magnet circuit

Permanent-magnet (PM) motors with both magnets and armature windings on stator (stator PM motors) have attracted considerable attention due to their simple structure, robust configuration, high power density, easy heat dissipation, and suitability for high-speed operations. However, they suffer from the problem of uncontrollable flux, thus limiting their constant-power operation for EVs. Also, they have the disadvantage of relatively high cost and potential resource issues because of rare-earth magnets are used. Currently, a new stator electrically wound field flux-switching (WFFS) motor with segmented-rotor and without rare-earth magnets have attracted considerable attention due to their simple and robust structure, low cost, no use of rare-earth magnet, wide speed operation range. However, the existing WFFS motors with segmented-rotor suffer from the drawbacks of asymmetry back-EMF and bigger torque ripple. The key of this paper is to propose a new general design method of WFFS motors with segmented-rotor and complementary magnet circuit.