大功率压接式IGBT模块的热学设计与仿真

Thermal Design and Simulation of High Power Press-pack IGBT Module

随着IGBT模块功率等级的提高,芯片的功率密度和工作结温大幅提升,导致器件长期可靠性受热应力的影响越来越大。本文以3 300 V/3 000 A规格压接式IGBT模块为例,对压接式IGBT模块热性能进行研究:分析了模块的传热模型并利用ANSYS对模块结构进行迭代仿真,发现模块双面散热存在不对称性;同时分析了模块结构对热阻的影响,并针对电极铜块面积、电极铜块厚度及钼片厚度等结构参数提出了优化方案,可为器件的结构优化设计提供参考。

With the improvement of packaging power level of IGBT module, power density and operating temperature on chip will rise, which may lead to an increasing affect of thermal stress on long-term reliability of the device. Taking 3 300 V/3 000 A press-pack IGBT module as example, it studied thermal resistance of the press-pack IGBT, analyzed its heat conduction model and took iterative calculation on module structure with ANSYS. The results show that the double-side heat dissipation structure is asymmetry. Furthermore, influence of the structure on heat resistance was analyzed and an optimized method was proposed aiming to the structure parameters such as area and thickness of electrode pad, thickness of molybdenum plates, etc., which could provide a reference for design optimization of IGBT device.