基于傅里叶级数解析热扩散角的功率模块热阻抗物理模型  

Physics-based Thermal Impedance Model for Power Module by Analytic Fourier Series Based Heat Spreading Angle

作　　者：陈宇[1] 吴强 周宇[1] 常垚 罗皓泽[1] 李武华[1] 何湘宁[1] CHEN Yu;WU Qiang;ZHOU Yu;CHANG Yao;LUO Haoze;LI Wuhua;HE Xiangning(College of Electrical Engineering,Zhejiang University,Hangzhou 310027,Zhejiang Province,China)

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《中国电机工程学报》2022年第2期715-727,共13页Proceedings of the CSEE

基　　金：国家自然科学基金杰出青年科学基金项目(51925702);国家自然科学基金面上项目(51677166);浙江省自然科学基金项目(LQ21E070006)。

摘　　要：绝缘栅双极型晶体管功率模块失效主要由温度因素诱发。为提高功率模块可靠性,RC热阻抗模型被提出用于实时预测芯片结温。随着功率密度的提高,模块横向扩散愈发明显,多芯片热耦合效应愈加突出,导致传统RC模型会引入较大误差。文中针对RC模型精准度不足进行改进,揭示热扩散角取决于热流密度的物理内涵,结合多层封装结构下的傅里叶级数解析热流模型,建立一维RC热网络与三维热流物理场的本质联系,构造计及多芯片热路耦合的扩散角热网络,较为准确地描述多芯片结温动态特性,揭示热扩散与热耦合效应对芯片温度场形成的规律。与其他传统热扩散角模型相比,所提出方法的结温计算结果准确度最高。最后以型号SEMiX603GB12E4p模块为例,针对提出的物理模型进行验证,仿真与实验结果均表明,该模型能够表征不同工况条件下功率模块的热过程,验证了所提建模方法的有效性与准确性,误差小于4%,且验证了所提模型较不计及热耦合模型精度提高了16.72%。Insulated gate bipolar transistor(IGBT)power module failure is mainly induced by temperature.In order to improve the reliability of the power module,the RC thermal impedance model was proposed to realize the junction temperature real-time prediction.With the increase of power density,the transverse heat conduction effect becomes outstanding,the thermal coupling effect was serious.There was a large error in the junction temperature calculation for the traditional RC model.In this paper,the physical law that the thermal diffusion angle depends on the heat flux density was revealed.Combined with the Fourier series analytical heat flux model for the multilayer package structure,the relationship between the 1-D RC thermal network and the 3-D heat flux field was established.The diffusion angle based thermal network considering the multi-chip thermal coupling was constructed,which realized the description of the multi-chip dynamic thermal characteristics.The physical principle of thermal diffusion effect and thermal coupling effect on the junction temperature field was revealed.Compared with traditional thermal diffusion angle models,the junction temperature results of the proposed method had the highest accuracy.Finally,the power module SEMIX603GB12E4P was tested to verify the proposed model.The simulation and experimental results demonstrate that the proposed model characterizes accurately the dynamic thermal process under different working conditions,which validates the effectiveness and accuracy of the proposed modeling method.The error is less than 4%,and the conclusion that the accuracy of the proposed model is 16.72%higher than that of the traditional model is validated.

关 键 词：功率模块 热扩散角 热耦合 热流密度 傅里叶级数 

分 类 号：TM464[电气工程—电器]