A novel tubular single‐phase linear generator with an axially magnetized permanent magnets (PM) mover is proposed in this paper for the application of free‐piston engine, which is an alternative power generation system of next‐generation electric vehicle. The transient 3D with motion electromagnetic field finite element model is created to analyze the EMF and thrust force characteristics of the linear generator. A 1.4 kW prototype with the max stroke of 40 mm and the max thrust force of 1670 N is developed, and main performances of the prototype are tested and validated with the finite element simulation. The prototype generating efficiency of 84 and 91% can be obtained respectively when driving by the 35 and 50 Hz sinusoidal reciprocation motion. Compared with the existed moving coil linear generator with similar generating efficiency, the mass power density and the volumetric power density of the new linear generator increase by about 37 and 80%, respectively. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

中文翻译：

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带轴向磁化永磁运动的管状单相线性发电机，用于自由活塞发动机

本文提出了一种新颖的带有轴向磁化永磁体（PM）的管状单相线性发电机，用于自由活塞发动机的应用，这是下一代电动汽车的替代发电系统。建立了带有运动电磁场的瞬态3D有限元模型，以分析线性发电机的电动势和推力特性。开发了最大行程为40 mm，最大推力为1670 N的1.4 kW原型，并通过有限元模拟对原型的主要性能进行了测试和验证。通过35 Hz和50 Hz正弦往复运动驱动时，分别可获得84％和91％的原型生成效率。与现有的具有类似发电效率的动圈式线性发电机相比，新线性发电机的质量功率密度和体积功率密度分别增加了约37％和80％。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。