A linear generator system based on a free-piston engine is expected to be a highly efficient power-generation engine for series hybrid vehicles. However, the engine generator must produce in a limited installation space the very high power required to drive a car. Consequently, considering the car-mounting situation, higher power density is required by means of reduced generator size and higher efficiency. In this paper, a cylindrical double-stator linear synchronous generator with opposing permanent magnets is used for free-piston engine. The double stator realizes smaller size, and using opposing magnets achieves a larger thrust constant than that with a single stator. In a finite-element analysis, the high-efficiency area is expanded compared to a surface-magnet type of the same size. Furthermore, this paper clarifies the effectiveness for improved power density with maximum-generation control in a simulation of a dual-sided engine model.

中文翻译：

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通过在双自由活塞发动机发电机中组合双定子和反磁体线性发电机来实现高功率密度

期望基于自由活塞发动机的线性发电机系统将成为用于串联混合动力车辆的高效发电发动机。然而，发动机发电机必须在有限的安装空间中产生驱动汽车所需的非常高的功率。因此，考虑到汽车的安装情况，通过减小发电机尺寸和提高效率需要更高的功率密度。本文将具有相对永磁体的圆柱形双定子线性同步发电机用于自由活塞发动机。双定子实现了更小的尺寸，并且与单个定子相比，使用相对的磁体实现了更大的推力常数。在有限元分析中，与相同尺寸的表面磁体类型相比，高效区域得到了扩展。此外，