This paper proposes an analytical model for analyzing the electromagnetic performance of axial flux permanent magnet machines (AFPMMs) with the coexistence of static rotor radial deviation and angular eccentricity. Firstly, a quasi-3-D analytical model for the healthy AFPMMs is established using the scalar potential. Then, the analytical model of AFPMMs with the mixed eccentricity is derived by the coordinate transformation and air gap length function. The end effect under the mixed eccentricity is considered by an end coefficient, which improves the accuracy of back EMF by 1.3%. Based on the analytical model, the air gap flux density distribution, back EMF and cogging torque of AFPMMs with different rotor radial distances and angular eccentricities are calculated and compared with the corresponding results obtained by finite element analysis (FEA). The proposed model has higher analysis speed and less computer performance requirement than FEA with the similar accuracy. According to the results, the back EMF reduces obviously as the rotor radial deviation distance increases, and the back EMF almost unchanged as the angular eccentricity becomes serious.

中文翻译：

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转子径向偏差和偏心角共存的轴向磁通永磁电机的建模与分析

本文提出了一种分析模型，用于分析同时存在静态转子径向偏差和偏心角的轴向磁通永磁电机 (AFPMM) 的电磁性能。首先，使用标量势建立健康 AFPMM 的准 3-D 分析模型。然后，通过坐标变换和气隙长度函数推导出混合偏心AFPMM的解析模型。混合偏心下的端部效应采用端部系数考虑，反电动势精度提高1.3%。基于解析模型，气隙磁通密度分布，计算了具有不同转子径向距离和偏心角的 AFPMM 的反电动势和齿槽转矩，并与有限元分析 (FEA) 获得的相应结果进行了比较。所提出的模型比具有相似精度的有限元分析具有更高的分析速度和更少的计算机性能要求。结果表明，随着转子径向偏差距离的增加，反电动势明显减小，随着偏心角变大，反电动势几乎没有变化。