Due to the high cost and shortage of rare earth materials, electrically excited synchronous machines (EESMs) become a potential alternative for electric vehicles. With the help of inductive power transfer (IPT), the EESM would easily realize the brushless excitation to improve its reliability. However, the dependence of IPT and EESM leads to significant control challenge, especially considering the inductive load characteristics. When the traditional modeling approaches are applied to the whole system, a complicated 13th-order model is built, which is unfavorable for dynamic analysis. For simplification, this article proposes a systematic and universal reduced-order model approach based on the local linear approximation of resonant voltage/current. A reduced ninth-order model of system is then obtained based on the approach. The frequency domain characteristic of primary-side control is analyzed, and the reduced-order model has high accuracy compared with the full-order one. Finally, the experimental results are given out to verify the effectiveness of the proposed modeling method.

中文翻译：

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基于线性逼近的无线励磁机降阶模型


由于成本高且稀土材料短缺，电励磁同步电机（EESM）成为电动汽车的潜在替代品。借助感应电能传输（IPT），EESM可以轻松实现无刷励磁，从而提高其可靠性。然而，IPT 和 EESM 的依赖性导致了重大的控制挑战，特别是考虑到感性负载特性。当传统的建模方法应用于整个系统时，会建立复杂的13阶模型，不利于动态分析。为了简化，本文提出了一种基于谐振电压/电流局部线性近似的系统且通用的降阶模型方法。然后基于该方法获得了系统的简化九阶模型。分析了原边控制的频域特性，降阶模型比全阶模型具有更高的精度。最后给出实验结果，验证所提建模方法的有效性。