A Novel Flux Switching Permanent Magnet Machine Based on Quantitative Air-Gap Construction Method

For ship propulsion, wind generation, and other applications, there are the urgent demands for the high torque density machine. Benefited from flux modulation effects and easy thermal management, FSPM machines can be a promising candidate. To further improve torque density, this paper proposes a novel FSPM machine with non-uniform auxiliary tooth by quantitative air-gap construction method. Endowed with the special stator structure, the additional stator permeance harmonics are introduced, which contribute the production of higher working flux density harmonic and torque density. Especially, under the same magnet usage and geometric dimension, both the no-load and on-load electromagnetic performances of the proposed FSPM are compared with the conventional FSPM by finite element analysis (FEA), including no-load magnetic field, phase back electromotive force (EMF), electromagnetic torque, loss and efficiency. It indicates that comparing to the conventional FSPM machine, the torque density of proposed FSPM machine can be enhanced from 19.2 Nm/L to 23.4 Nm/L at the electric loading of 160 A/cm, which verifies the superiorities of the proposed FSPM machine.