Abstract：When obtaining the closed expressions of permanent magnetic spherical motor’s electromagnetic torque, it relies on the analysis results of rotor and stator magnetic field. Currently, the main method to solve the spatial distribution of stator magnetic field is numerical solution analysis. However, it can’t give the forms of expressions. The paper presents a solution to get the different orders of harmonic coefficients by decomposing the magnetic field of stator coil on the surface of a stator sphere, which makes the use of least square method that uses the spherical harmonic series as its basic function. The whole process is on the basis of magnetic equivalent circuit method, and it compares the accuracy of magnetic fitting in different orders. The result shows that in the order of 20, the fitting errors of BRand Bθare 0.78% and 1.95%, which reaches the approximate analytical formula of stator coil. The research of the paper provides a basis for the analysis of electromagnetic torque.
李斌, 翟雪冰, 李桂丹, 李洪凤. 永磁球形电机定子磁场的球谐波分析[J]. 电工技术学报, 2013, 28(1增): 302-306.
Li Bin, Zhai Xuebing, Li Guidan, Li Hongfeng. The Spherical Harmonics Analysis for the Stator Magnetic Field of Permanent Magnetic Spherical Motor. Transactions of China Electrotechnical Society, 2013, 28(1增): 302-306.
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