Research on on-line monitoring technology of IGBT module junction temperature based on Kalman filter

Abstract

IGBT is the core device of energy conversion and transmission, commonly known as the CPU of power electronic devices. However, with the continuous improvement of IGBT power density, its reliability is increasingly concerned by industry and academia. The failure of IGBT module is mainly related to the average junction temperature and the amplitude of junction temperature fluctuation, and with the increase of the amplitude of junction temperature fluctuation, the number of failure cycles of IGBT module will sharply decrease. It can be seen that the change of junction temperature in power module is the key to affect its fatigue life. In this paper, an on-line junction temperature monitoring method based on Kalman filter is proposed, which combines the actual temperature measured by IGBT module with the junction temperature obtained by RC thermal network, so it has the advantages of high reliability and real-time on-line monitoring. The simulation results show the effectiveness of the method.