In this article, the implementation of a single-stator double-rotor fractional-slot concentrated-winding (FSCW) axial-flux permanent-magnet machine is presented to verify a simple and reliable structure design and oil-immersed cooling of the stator with modular soft magnetic composites (SMC) core. Due to the yokeless and segmented stator, the process of embedding the windings into the stator teeth will probably become simpler. By preforming rectangular copper wire, the shorter end-winding length and higher fill factor can be achieved. In order to eliminate eddy current losses and manufacturing costs, the fiberglass epoxy is used for the supporting components of the fixation for modular SMC stator and PMs, which is a nonmagnetic and nonconductive material. Hence, the robustness of stator and rotor are taken into account due to the stator modularity weakening effect on strength. Meanwhile, a fully sealed stator with oil-immersed cooling is proposed to enable the current density of 20 A/mm2 in the armature windings for stable operation. The electromagnetic properties, including in magnetic field distribution, torque capacity, and flux-weakening ability, are performed based on the three-dimensional finite-element analysis, as well as the mechanical performance. The coupled thermal and computational fluid dynamics model is built to predict the flow and temperature distribution inside stator with oil-immersed forced cooling. The construction and experimental verification of a full-scale 30-kW prototype are elaborated to verify the predicted performances in terms of torque density, structural strength, and cooling.

中文翻译：

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具有模块化SMC定子的高扭矩密度分数槽集中绕组轴向磁通永磁电机

在本文中，提出了一种单定子双转子分数槽集中绕组（FSCW）轴向磁通永磁电机的实现，以验证一种简单可靠的结构设计和带有模块化定子的油浸冷却软磁复合材料 (SMC) 磁芯。由于采用无轭和分段定子，将绕组嵌入定子齿的过程可能会变得更简单。通过预成型扁铜线，可以实现更短的端部绕组长度和更高的填充因子。为了消除涡流损耗和制造成本，玻璃纤维环氧树脂被用作模块化 SMC 定子和 P​​M 固定装置的支撑部件，它是一种非磁性和非导电材料。因此，由于定子模块化对强度的削弱作用，考虑了定子和转子的鲁棒性。同时，建议采用油浸冷却的全密封定子，使电枢绕组中的电流密度达到 20 A/mm2，以实现稳定运行。电磁特性，包括磁场分布、扭矩容量和弱磁能力，是基于三维有限元分析以及机械性能进行的。建立耦合的热和计算流体动力学模型来预测油浸强制冷却定子内的流量和温度分布。详细阐述了全尺寸 30 kW 原型的构造和实验验证，以验证在扭矩密度、结构强度、