结温在线控制系统的IGBT功率模块热耦合模型

Thermal Coupling Model for IGBT Power Modules in an On-Line Temperature Control System

应用有限元法,对IGBT功率模块的三维热分布进行了仿真研究,得到了器件的稳态热阻及瞬态热阻抗。研究了功率模块各芯片之间的相互热影响,提出了热耦合效应热模型的统一结构,基于对瞬态热阻抗曲线的拟合,得到热模型的相关参数,从而建立了热耦合效应热模型。以一个降压变换器为例,阐述了结温在线控制系统的工作原理,并将热模型应用于该系统中,计算结果与测量结果非常一致。

The 3D finite element method is used to analyze the temperature distribution of an IGBT module The steadystate thermal resistance and transient thermal impedance of the device are obtained A thermal model with multichip thermal effects taken into consideration is set up,which is based on the fitting of the transient thermal impedance curve with a finite series of exponential terms Tests were done on an online chip temperature monitor Measured results are in good agreement with calculations