不等极弧系数对轴向磁通电机齿槽转矩抑制研究

Research on the Suppression of Groove Torque of Axial Flux Motor with Unequal Polar Arc Coefficient

摘要

齿槽转矩会恶化电机性能并降低系统稳定性,为削弱轴向磁通电机的齿槽转矩,提出了一种不等极弧系数的转子结构优化方法.以一台双转子单定子轴向磁通电机为研究对象,运用能量法与傅里叶分解推导出能表示轴向电机齿槽转矩与极弧系数关系的齿槽转矩表达式,并得到使齿槽转矩最小的永磁体极弧系数.在此基础上,以气隙磁场总能量不变为原则,基于理论推导和三维有限元分析,得到最佳不等极弧比,使齿槽转矩降低63%.对比优化前后的空载反电势、输出转矩和损耗,充分验证了上述方法的可行性与有效性.

Abstract

Cogging torque can deteriorate motor performance and reduce system stability. In order to weaken the cogging torque of axial flux motor, a rotor structure optimization method with unequal arc coefficients is proposed. The expression of slot torque, which establishes the relationship between slot torque and polar arc coefficient of an axial flux motor, is derived for a two-rotor single-stator axial flux motor using energy method and Fourier decomposition, and the polar arc coefficient of permanent magnet which minimizes the cogging torque is also obtained. Based on the principle that the total energy of the air gap magnetic field does not change, the optimum unequal pole arc ratio is obtained based on theoretical derivation and three-dimensional finite element analysis. The simulation results show that the cogging torque is reduced by 63%. The comparison of no load back potential, output torque and loss before and after optimization fully verifies the feasibility and effectiveness of the above method and analysis.

关键词

齿槽转矩 / 轴向磁通电机 / 不等极弧系数

Key words

cogging torque / axial flux motor / unequal polar arc coefficient

参考文献

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