IGBT模块实时温度反馈的动态热网络模型

Dynamic Thermal Network Model for Real-Time Temperature Feedback of IGBT Modules

IGBT模块中材料的热特性和传导特性与内部温度场分布密切相关,但传统热网络模型往往忽略这一特性,造成结温估计出现偏差。针对此问题提出了一种包含实时温度反馈修正的热网络模型,在考虑异质材料的热传导角度及导热系数等传热性质的差异性基础上,对热网络模型的RC参数进行了优化。本模型的电路仿真和迭代计算可直观反映热网络各节点温度和RC参数相互作用的动态过程,并与三维有限元仿真结果高度吻合。相较将材料传热参数固定的传统热网络模型而言,本方法不仅在结温估计方面更为精确,还可解决热网络对材料物理系数变化的实时响应需求,可应用于IGBT模块可靠性设计和检测。

The thermal and conduction properties of materials in IGBT modules are closely related to the internal temperature field distribution,while traditional thermal network model tends to ignore this characteristic,causing deviations in junction temperature estimation.A thermal network model which contains the real-time temperature feedback correction was proposed to solve this problem.On the basis of considering the difference in heat transfer properties of the heterogeneous material such as thermal conduction angle and thermal conductivity coefficients,the RC parameters of the thermal network model were optimized.The circuit simulation and iterative calculation of this model can directly reflect the dynamic process of interaction between temperature and RC parameters of each node of the thermal network,and it is highly consistent with the results of 3 D finite element simulation.Compared with the traditional thermal network model with fixed material thermal conduction parameters,this method is not only more accurate in junction temperature estimation,but also solves the real-time response requirement of the thermal network to the adaption of material physical coefficients.Therefore,it can be applied in the reliability design and detection of IGBT modules.