Cogging torque reduction in FSPM machines with short magnets and stator lamination bridge structure

Flux-switching permanent magnet (FSPM) machine is consist of a salient rotor and a salient stator with windings and magnets. Adding stator lamination bridge in segmented stator can simplify stator assembly significantly, which will be beneficial to manufacture and popularize the FSPM machine. Due to the doubly salient structure, the cogging torque in FSPM is larger than other traditional PM motors. In this paper, cogging torque of FSPM with stator lamination bridge is analyzed, and a novel short magnet (SM) structure is proposed to reduce the cogging torque by shortening the magnets. The simulation results indicate that shortening magnets reasonably can reduce the cogging torque at the cost of little output torque loss.