Abstract:The no load air gap magnetic field of claw pole motors with outer permanent magnet rotors(CPMOPMR) should be analyzed by 3D model due to its complicated structure. And, in view of the time consuming and sensitive to finite element meshes, the finite element method(FEM) is not suitable for analysis. So a new analytical calculation model based on no load air gap magnetic field analysis in polar coordinates is proposed. According to segmentation in shaft directions, 3D model is converted to many 2D models, then their boundary conditions are assigned, and the radial and tangential flux density is obtained by using the Fourier’s series and the method of separation of variables. Then the expression of cogging torque and no load back EMF is derived. In order to verify the accuracy of the analytical model, the finite element analysis is finished. Moreover, one prototype is manufactured and measured also. The analytical results well agree with those obtained by the FEM and experiments, and confirm the feasibility of this method.
刘光伟, 张凤阁, 魏瀚阳, 赵鑫. 外永磁转子爪极电机空载气隙磁场解析计算[J]. 电工技术学报, 2014, 29(1): 52-59.
Liu Guangwei, Zhang Fengge, Wei Hanyang, Zhao Xin. Analytic Model of No Load Air Gap Magnetic Field for Claw Pole <br/>Motor with Outer Permanent Magnet Rotor. Transactions of China Electrotechnical Society, 2014, 29(1): 52-59.
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