Abstract：Axial field flux-switching permanent magnet(AFFSPM) machine is a novel PM machine with high torque density and efficiency. The cogging torque in AFFSPM machine is larger than that in the traditional PM machine because of the flux focusing which is caused by the double salient structure. In order to decrease the cogging torque, the analytical expression of the cogging torque is deduced and the influence of the rotor teeth notching on the cogging torque is investigated. The mathematical model about the slot width, slot depth and slot fan angle is achieved by using design of experiment (DOE) and the optimal combination with the minimum cogging torque is obtained. The accuracy of the analysis is examined by the 3D finite element method(FEM). The results show that the cogging torque can be reduced by the rotor teeth notching and the cogging torque can decrease by 44.3% when the notching slot width, depth and shape are optimized to 3°, 1.79mm and 1.62°respectively.
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2015, Vol. 30 
