A Novel Double-sided PM Flux Modulated Machine with Hybrid Magnet Arrangement

This paper proposes a novel double-sided PM flux modulated machine (DPMFMM) with hybrid magnet arrangement, in which the Halbach-array PMs and spoke-array PMs are employed on the stator, and consequent pole PMs are employed on the rotor. With this design, the proposed DPMFMM can enjoy rich airgap flux density working harmonics to increase the torque density. The topology and operation principle of DPMFMM are introduced first. Based on a simplified magnetomotive force-permeance model, the flux field harmonics produced by the PMs of DPMFMM are comprehensively analyzed, which indicates that the superposition effect of the Halbach-array and spoke-array PMs can lead to a high contribution to the torque density. To confirm the merits of the proposed DPMFMM, comparative performance analyses with an existing DPMFMM that adopts uniformly distributed CP PMs on both the stator and rotor are performed using the finite element method. The comparison result demonstrates that the DPMFMM exhibits 41.4% higher torque density, 3.2% higher efficiency, and 33.3% higher PM utilization than its counterpart.