高空飞行器供油驱动系统IGBT模块结温特性研究

Research on junction temperature characteristic of IGBT module for high-altitude aircraft fuel system

对高空飞行器供油驱动系统在特定负载状态下的IGBT模块结温特性进行研究。高空飞行器对供油驱动系统的高功率密度要求高及环境散热条件差的状况,使得其关键部件IGBT模块在功率裕量与结温控制方面更为严格。根据负载特性精确计算结温,对于在特定散热条件下系统的可靠运行非常重要。运用非稳态导热的Foster集总参数法,分析IGBT模块点热源特性及其他热源对计算影响,建立一种含校正系数的热网络模型,并在短时脉冲过载及输出低频两种特有状态下,对IGBT模块的结温特性进行分析。通过对高空飞行器飞行过程中IGBT模块结温特性的计算,结合仿真软件Semisel的对比分析,验证了建模和分析本文所提方法的有效性。

Junction temperature characteristic of IGBT model is researched, which is applied to high-ahitude aircraft fuel system in certain load state. Owing to the requirement of high power density for the drive system providing fuel by high-altitude aircraft and poor heat dissipation condition, the key component of the IGBT modules in the power margin and junction tempera- ture control is strictly required. Calculating the junction temperature accurately according to the load characteristic is very important to the reliability service of system in particular c dissipation condition. Using the Foster lumped parameter method of un- steady heat transfer to analyze the point heat source characteristic of IGBT module and influence of other heat source on the calculation, and to establish a thermal network model with correction coefficient. The junction temperature characteristic of IGBT model in transient pulse overload and low output frequency is analyzed. Through the calculation of the junction temperature characteristic of IGBT model during the whole flight process of high-altitude aircraft, and combining comparative analysis with Semisel simulation software, the validity of the modeling and the proposed method in this paper is verified.