Design of a Split-slot Dual-Permanent-Magnet-Excited Machine Based on Torque-Loss-Ratio

High torque density can be achieved in a Dual-permanent-magnet-excited machine (DPMEM). However, this type of machine usually suffers from the high core loss due to the dual-PM structure. In this paper, by introducing the concept of Torque-Loss-Ratio (TLR), design with low core loss and high torque density can be achieved simultaneously. Firstly, based on bi-directional field modulation effect (BFME), a novel split-slot DPMEM is proposed. Then, the relationships between TRL and design parameters are studied, and the suitable TRL is chosen for this proposed machine. Finally, the electromagnetic performances are analyzed, including no-load back-electromotive force, torque performances, and core loss. The finite element computation result verifies the effectiveness of the proposed concept of TLR.