Torque Performance and Flux-Adjustment Capability Analysis of Novel Separated Excitation Axial Field Hybrid Permanent Magnet Memory Machine

This paper proposes a novel separated excitation axial field hybrid permanent magnet memory (SE-AFHPMM) machine with high torque density and excellent flux-adjustment capability. The topology and operating principle of the proposed machine are presented. Comparisons are made on the machine with different slot/rotor pole combinations in terms of torque capacity and flux-adjustment capability by 3-D finite element analysis. It is found that higher torque density and better flux-adjustment capability can be achieved by the proposed 12/10 machine. Moreover, the PM torque is the primary component of the output torque in the flux-enhanced state, whereas in the flux-weakened state, the reluctance torque exhibits an important role and becomes the main component of the output torque. Finally, to evaluate the contribution of different PMs to the output torque, frozen permeability method is used to separate PM torque components for both types of PMs. The results reveal that the torque contributed by the AlNiCo of the 12/10 SE-AFHPMM machine is the largest in the total output torque, which is suitable for various magnetization occasions.