Internal thermal-force distribution characteristics and optimization of the elastic crimping IGBT device

Abstract

With the rapid development of power electronics technology, especially the development of the fully controlled device IGBT, flexible high-voltage direct current transmission (HVDC) technology has become a new generation of HVDC technology, the core of which is the use of insulated-gate bipolar transistor (IGBT) and other fully controlled devices. The crimped IGBT device, with its advantages of high reliability and failure short circuit, is becoming a hot topic at present. This paper takes 3000A elastic crimping IGBT as the research object, builds the physical model through SolidWorks, removes the sub-module frame and model outside frame, and simplifies the process. At the same time, the thermal-force coupling finite element analysis of the device was carried out through COMSOL multi-physical field simulation software, and the mechanical and thermal distribution characteristics of the device during the steady state operation were studied. The key points of the chip are prone to failure fatigue during the steady state operation, and the key chips with a strong coupling effect when multiple chips are connected in parallel were found out. By improving the layout of the chip, reducing the thermal coupling with other chips, and decreasing the mutual thermal resistance between chips, heat can be more efficiently transferred to the heat dissipation structure through the electrodes, which can significantly reduce the junction temperature of the chip. The equalization method of thermal-force equalization control provides some guidance for further structural optimization of the device.