综合考虑材料热各向异性与多种传热方式的磁性元件热阻网络精准模型  

An Accurate Thermal Resistance Network Model for Magnetic Elements Considering Thermal Anisotropy of Materials and Various Heat Transfer Ways

作　　者：郭轩 肖云昊 李驰 郑泽东[1] Guo Xuan;Xiao Yunhao;Li Chi;Zheng Zedong(State Key Laboratory of Control and Simulation of Power System and Generation Equipment Tsinghua University,Beijing 100084 China)

机构地区：[1]电力系统及大型发电设备安全控制与仿真国家重点实验室(清华大学),北京100084

出　　处：《电工技术学报》2024年第6期1806-1817,共12页Transactions of China Electrotechnical Society

摘　　要：磁性元件正在向高频化、小型化、高功率密度的方向发展,随着功率密度的提高,散热已成为影响器件可靠运行的关键因素,因此对磁性元件的热分析提出更高的要求。传统的热分析模型存在运算时间长、传热方式单一等问题,该文引入已有研究中提出的三轴九热阻网络模型,在此基础上添加热对流与热辐射两种传热方式,综合考虑材料热各向异性与热传导、热对流、热辐射。并通过精细划分元件温度计算子区域、实际器件损耗场分析、热电耦合迭代提高模型的计算精度,提出一种更加完善的三轴十五热阻网络模型,基于该模型对实际磁性器件建模,验证了该模型的准确性,并于最后提出一种通用的针对EE、EI、UU等典型磁心构成的磁性元件的热阻网络建模方法。The development trend of magnetic components is higher frequency,smaller volume,and higher power density.With the increase of power density,heat dissipation becomes a key factor affecting the reliable operation of magnetic components,which puts forward higher requirements for the thermal analysis of magnetic components.The traditional thermal analysis models have problems such as long calculation time and single heat transfer way.In addition,the thermal anisotropy,different distribution of loss density in magnetic core and interaction effect between temperature and loss are usually ignored.A precise and generalized analytical thermal modeling method is needed to meet the calculation requirements of the magnetic component optimization design and match the actual working condition with complex heat dissipation ways.The inductor made of an EE-type magnetic core is taken as an example,and the three-axis nine-thermal-resistance network model with thermal anisotropy is introduced for solving the heat conduction problem.A three-axis fifteen-thermal-resistance network model was proposed considering multiple heat transfer ways,thermoelectric coupling,material thermal anisotropy,and actual loss distribution of magnetic core.For multiple heat transfer ways,the influence of heat conduction,heat convection,and heat radiation should be considered because high-power density magnetic components are often used with water cooling,air cooling,or other cooling structures.Moreover,the influence of heat convection and heat radiation has been considered in the model as air thermal resistances.The magnetic field distribution influences the loss density distribution in each area.The loss distribution of the magnetic core is calculated by the 2D finite element simulation of the actual magnetic field to match the actual condition.The loss of winding and magnetic core requires iterative calculation because the temperature affects the magnetic core’s iron loss density and copper’s electrical conductivity.In contrast,the winding loss and

关 键 词：磁性元件 材料热各向异性 多种传热方式 实际损耗分布 集总参数热阻网络 

分 类 号：TM47[电气工程—电器]