A New Dual-Permanent-Magnet-Excited Motor with Hybrid Stator Configuration for Direct-Drive Applications

This paper proposes a new hybrid-stator dual-permanent-magnet-excited (HS-DPME) motor for direct-drive applications. Compared with the existing straight-tooth-stator dual-permanent-magnet-excited (STS-DPME) motors, its notable structural features are that the stator employs a so-called hybrid stator, by combining a straight-tooth stator and a split-tooth stator; stator permanent magnets (PMs) with unified direction of magnetization are surface-mounted under the straight and split teeth, and each two adjacent PMs are either separated by a straight tooth or by a split tooth. The major benefit of the proposed motor is to reduce the consumption of precious PMs, especially the stator PMs. Nevertheless, simulation results obtained by finite element method (FEM) show that performances of the proposed motor can be comparable to that of the existing STS-DPME motors, including cogging torque, back-EMF, torque capability, torque ripple and speed-extension capability. Moreover, working principle of the proposed motor and influence of slot-pole combination are also discussed in this paper.