Thermal analysis and improvement of high power electronic packages

High power electronic modules, such as IGBT modules, are required in many applications, like the high speed train, solar energy inverter, CNC, frequency-alterable air-conditioner, etc. When a module works, a lot of heat would be generated due to the small size. If the heat could not be removed from the module, the high heat flux might lead to failure of the module. Therefore, a good thermal management is very important for its reliability. In this paper, a 600V 50A IGBT module was investigated. By using dissection method, the internal structure and components of the module were obtained. In addition, the electric characteristics of the module was analyzed and an electric model was built. The power losses, which would be converted into heat, were also discussed. Finally, a finite element model was built to investigate the thermal performance of the module, and the results showed that traditional heat dissipation method, like forced air cooling method, cannot meet the requirement of thermal management, even the heat transfer coefficient is 500W/m²*K. Therefore, two micro channels, one is spiral and the other is discrete, were designed to enhance the heat dissipation. The thermal performance of IGBT modules with micro channel was analyzed by using CFD (computational fluid dynamics) method. The results showed the maximum temperature is about 360K after the micro channels were employed. Thus the micro channel would be a very effective way for cooling high power electronics. The effectiveness of the types of micro channel were also compared. It is found that the discrete micro channel is better than the spiral one.