This paper presents a new rotor shape design with optimum reverse 3rd harmonic for wound field synchronous machines to effectively enhance the saliency ratio and reduce the torque ripple in a micro electric vehicle traction system. Due to the enhanced saliency ratio, the reluctance torque is expected to be improved. The air gap flux density distribution is reshaped by the new rotor shape method, which benefits the low torque ripple. By contrast, the reverse 3rd harmonic injection is much more suitable than the general 3rd harmonic injection for increasing the effective air gap length along the q-axis for a high saliency ratio. Subsequently, three amplitudes of the reverse 3rd harmonic are studied and it is found that the optimum reverse 3rd harmonic is 1/6 of the fundamental one. To verify the effectivity of the proposed design, the original model and the ICS model are compared. Finally, all the motor characteristics, such as back electromotive force, cogging torque, and electromagnetic torque, are predicted using a 2-D finite-element method with the aid of JMAG-Designer.

中文翻译：

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通过在转子形状中注入最佳谐波来增强绕线励磁同步电机的显着性并降低转矩纹波

本文提出了一种新的转子形状设计，该绕组形状用于绕线励磁同步电机具有最佳的反向三次谐波，可有效提高微电机牵引系统中的显着比并减小转矩脉动。由于显着性比提高，因此期望磁阻转矩得到改善。气隙磁通密度分布通过新的转子形状方法进行了整形，这有利于降低转矩脉动。相比之下，反向3次谐波注入比普通的3次谐波注入更适合于增加沿q轴的有效气隙长度，以实现较高的凸度比。随后，研究了反向三次谐波的三个幅度，发现最佳反向三次谐波为基频的1/6。为了验证所提出设计的有效性，比较原始模型和ICS模型。最后，借助JMAG-Designer使用2-D有限元方法来预测所有电动机特性，例如反电动势，齿槽转矩和电磁转矩。