提高电机系统的运行频率能有效提升其功率密度与效率，但也增加磁芯损耗导致电机局部温升过高从而限制电机性能进一步提高，因此降低电机高频磁芯损耗具有重要意义。本项目提出应用混合材料磁芯设计电机定子降低电机高频磁芯损耗，内容包括：研究工作于电机磁场中的硅钢片-取向硅钢片、硅钢片-软磁复合材料两种混合材料磁芯拓扑设计方法，测量其高频磁特性并与硅钢片材料进行对比分析；研究驱动电机混合材料磁芯拓扑结构，分析混合材料磁芯对电机损耗与性能的影响规律；以温升、成本、效率为目标，研究混合材料磁芯电机的多物理场快速优化方法，获得电动汽车驱动电机混合材料磁芯结构与工况之间的耦合关系；制作试验样机，验证混合材料磁芯设计方法与理论分析的可行性。最终解决工作于电机典型电磁场中的混合材料磁芯拓扑理论及混合材料磁芯与电机在不同工况中磁芯损耗和功率密度的内在联系等科学问题，为电动汽车驱动电机磁芯设计提供理论参考。

Increasing operation frequency is the key for power density and efficiency improvement of electrical machine system, however core loss will be increased greatly as well which will bring the electrical machine with very high temperature rise and moreover it limiting the machine performance to be improved furtherly, therefore reducing high frequency core loss in electrical machine is very important. This project investigates electrical machine with hybrid magnetic cores and thus the high frequency core loss in stator core will be reduced, including hybrid magnetic core topology design method of silicon steel - grain-oriented silicon steel and silicon steel - soft magnetic composite material working in the electrical machine magnetic field, measuring their high frequency magnetic characteristic and comparing these with the silicon steel’s, then studying hybrid magnetic core design method for driving machine, analyzing the influence of flux density distribution and core loss of the electrical machine by using hybrid magnetic core, studying the multi physical fast optimization method with the temperature rise, material cost and efficiency as the objective target, obtaining the optimized dimensions of the hybrid magnetic core and other design parameters for driving machine under different work condition. Building prototype, concluding parameters and comparing overall performance, verifying hybrid magnetic core design method and the feasibility of theoretical analysis. Finally, the theory of hybrid magnetic core working in electrical machine magnetic field and the internal relation between the hybrid magnetic core to core loss and power density of electrical machine will be solved. The research results of this project can provide theoretical reference of magnetic core design method for driving machine.