This paper proposes a novel tiered type permanent magnet spherical motor (T-PMSPM) of which the output torque is relatively higher than that of the most existing spherical motors. The proposed T-PMSPM has three stators along axial direction; each of the stator is consisted of an iron core and a three-phase winding. An analytical method is developed in order to calculate the tilting torque based on the air gap magnetic field distribution generated with the specific pole_slot combinations. For performance verification and accurate calculation, three-dimensional finite-element analysis (FEA) is adopted. Two typical rotor configurations are compared and analyzed, focusing on the ability of large torque production, especially for the tilting torque. Finally, a prototype motor as well as the auxiliary apparatus used for experimental measurements has been manufactured. Considering that the friction torque is nonnegligible, a test procedure of torque measurement and separation is designed and performed. The tilting torque obtained from the experiments is compared with the FEA results after friction compensation.

中文翻译：

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新型分层式永磁球形电机的倾斜扭矩计算


本文提出了一种新型分层式永磁球形电机（T-PMSPM），其输出扭矩比大多数现有球形电机的输出扭矩相对较高。所提出的 T-PMSPM 沿轴向具有三个定子；每个定子由铁芯和三相绕组组成。开发了一种分析方法，以便根据特定极槽组合生成的气隙磁场分布来计算倾斜扭矩。为了进行性能验证和精确计算，采用三维有限元分析（FEA）。对两种典型的转子结构进行了比较和分析，重点关注产生大扭矩的能力，特别是倾斜扭矩。最后，制作出了原型电机以及用于实验测量的辅助装置。考虑到摩擦扭矩不可忽略，设计并执行了扭矩测量和分离的测试程序。将实验获得的倾斜扭矩与摩擦补偿后的有限元分析结果进行比较。