Abstract：Cogging torque is an important aspect of permanent magnet (PM) generator design. In this paper, the cogging-torque waveform results due to a single slot and the synthesized waveform result due to slots are studied based on the Fourier analysis. A method of slot-opening shift to reduce cogging torque of permanent magnet machine is presented. The results show that, several lower-order harmonics of cogging torque could be eliminated by the method of slot-opening shift. The method to obtain the slot-opening shift angles is given. At last the method is verified by finite element method. The results verify that the cogging torque can be greatly reduced by this method and the conclusions are validated.
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2013, Vol. 28 
