The linear permanent magnet vernier (LPMV) machines have been paid more attention in railway vehicles because of its simple structure and low cost. In this paper, the ring type winding (RTW) is adopted in both non-modular and modular LPMV machines to improve force density. The configuration and operating principle of two LPMV-RTW machines are presented. The coil connection and mechanism of RTW are explained and compared with conventional distributed winding (DW) and concentrated winding (CW). The back electromotive force and thrust force are investigated by the time-stepping finite-element method. It is found that non-modular LPMV-RTW machine possesses larger force density than non-modular LPMV-DW machine while modular LPMV-RTW machine has higher force density and utilization ratio of winding than modular LPMV-CW machines under the constant copper loss. Finally, the experiment result is obtained on the prototype, verifying the theoretical analysis.

中文翻译：

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直线永磁游标机环形绕组提高力密度的机理研究

线性永磁游标(LPMV)电机因其结构简单、成本低而在轨道车辆中受到越来越多的关注。在本文中，非模块化和模块化 LPMV 电机均采用环形绕组 (RTW) 来提高力密度。介绍了两台 LPMV-RTW 机器的配置和工作原理。解释了 RTW 的线圈连接和机理，并与传统的分布式绕组 (DW) 和集中绕组 (CW) 进行了比较。反电动势和推力通过时间步长有限元方法进行研究。发现非模块化LPMV-RTW电机比非模块化LPMV-DW电机具有更大的力密度，而在恒定铜损下，模块化LPMV-RTW电机比模块化LPMV-CW电机具有更高的力密度和绕组利用率。最后在样机上得到实验结果，验证了理论分析。