基于解析法的表贴式永磁同步电动机电磁场与齿槽转矩的分析

Analysis of electromagnetic field and cogging torque of surface mounted permanent magnet synchronous motor based on analytic method

永磁电动机由于结构简单、运行可靠等优点得到了广泛的应用。然而电动机开槽会改变电动机的结构和磁路,导致气隙磁场发生畸变,同时还会产生齿槽转矩,引起噪声和振动。齿槽作用下的电磁场分布可以用有限元法解决,但该方法计算周期较长,计算结果对剖分比较敏感,相较之下,解析法计算时间短,且能给出电动机性能与设计参数之间的数学关系。针对齿槽作用下的表贴式永磁同步电动机的空载磁场,本文提出了一种基于精确子区域方法的解析模型,计算了空载磁场的径向磁密和切向磁密,并根据麦克斯韦应力法得到齿槽转矩,最后经有限元仿真验证了该方法的准确性。

Permanent magnet motor has been widely developed because of its simple structure, reliable operation and so on.However, the slotting of the motor will change the structure and magnetic circuit of the motor, resulting in the distortion of the air gap magnetic field, and generating cogging torque, which will result in noise and vibration. The electromagnetic field distribution under the influence of slotting can be solved by the finite element method. However, the calculation cycle is long and the calculation results are sensitive to the subdivision. In comparison, the analytical method has a short computational time, and can give the mathematical relationship between the motor performance and the designed parameters. An analytical model based on the exact sub region method is proposed for the no-load magnetic field distribution of a surface-mounted permanent magnet synchronous motor (PMSM) considering slotting effects.