An optimization method of the piecewise stagger trapezoidal poles is proposed for the reduction of the pole-frequency vibration of the surface-mounted permanent magnet synchronous machines (SPMSMs) in this article. By offsetting the zero-crossing region of flux density, this method can weaken the pole-frequency force harmonic while ensuring the torque density. First, based on the Maxwell tensor method, the analytical model of concentrated force acting on the teeth is deduced. Taking a 10-pole/12-slot SPMSM as an example, the deep cause of the pole-frequency radial force harmonic is analyzed. Then, the weakening mechanism of the piecewise stagger trapezoidal poles for the pole-frequency radial force harmonic is revealed with the finite-element model (FEM). Based on the multiphysics coupling model, the key electromagnetic properties and vibration spectrum between the common and proposed motors are compared. The results show that the piecewise stagger trapezoidal pole structure has a significant suppression effect on the pole-frequency vibration. Finally, the vibration experiment of the two prototypes is carried out, and the effectiveness of the optimized structure is verified.

中文翻译：

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分段错列梯形磁极表贴式永磁同步电机极频振动的降低

本文提出了一种分段交错梯形磁极优化方法，以降低表面贴装永磁同步电机 (SPMSM) 的极频振动。该方法通过抵消磁通密度的过零区域，在保证转矩密度的同时削弱极频力谐波。首先，基于麦克斯韦张量法，推导了作用在牙齿上的集中力的解析模型。以10极12槽SPMSM为例，分析了极频径向力谐波产生的深层原因。然后，利用有限元模型 (FEM) 揭示了分段交错梯形极点对极频径向力谐波的削弱机制。基于多物理场耦合模型，比较了普通电机和建议电机之间的关键电磁特性和振动频谱。结果表明，分段交错梯形磁极结构对极频振动具有显着的抑制作用。最后对两台样机进行了振动实验，验证了优化结构的有效性。