气隙偏心永磁电机绕组感应电势的快速计算与分析

Fast Calculation and Analysis of Electromotive Force of Permanent Magnet Motors with Air-Gap Eccentricity

制造过程中安装误差不可避免,复杂环境中长时间运行会导致轴承磨损,电机普遍存在不同程度的气隙偏心问题,分析气隙偏心后电机的性能对系统可靠性研究有重要意义。针对斜槽电机有限元建模复杂、求解耗时的问题,采用了一种由二维场分析数据合成三维场计算结果的等效算法,将整台斜槽电机分解成若干个直槽电机单元的串联形式,计算和分析了气隙偏心前后的表贴式无刷直流电机。针对样机数据,分析了等效算法的计算精度,对比了偏心前后的气隙磁场和感应电势。研究表明:气隙偏心会影响表贴式无刷直流电机的磁场分布,进而改变一相绕组中不同轴线位置的各个元件的感应电势,但绕组整体的感应电势却几乎不发生变化。研究结果能够为电机可靠性分析提供理论依据。

Position errors in manufacturing process and bearing wear in long-running operations are unavoidable.There are air-gap faults in electrical machines catholically in different degrees and it is of significance to analyze the performance of eccentric motor for the research on the driving system's operational reliabilities.Although the modeling process of a three-dimensional finite element model is extraordinarily cockamamie and it is a long wait before the model is solved,the three-dimensional finite element model is built to calculate the performance of the skew-slot electrical machine customarily.The two-dimensional finite element calculation results are translated into three-dimensional finite element calculation results.A skewed slot motor is decomposed into a certain number of straight slot motor units which are series-wound.The brushless direct-current motor with and without rotor eccentricity are calculated and the calculation results are contrasted.Aiming at the real prototype,the computational accuracy of the equivalent algorithm is analyzed and the air-gap magnetic field and induced electromotive forces are calculated and contrasted.The results show that the magnetic field distribution and the induced electromotive forces of series-wound winding elements with different axis positions is affected by air-gap eccentricity,yet the induced electromotive forces of one phase winding remain unchanged.The references to reliability analysis of motor system are provided.