A Novel Junction Temperature Extraction Technology of On-Line Reliability State Detection for IGBT Module

Abstract

In recent years, IGBT (Insulated Gate Bipolar Transistor) is being more and more widely used in many fields such as new energy generation system, electric vehicle, smart grid and so on. To keep IGBT run stably and reliably is the basis of normal operation of these equipments so the reliability state detection of IGBT modules has become one of the research hotspots in power electronics fields. Many existing researches show that the key factor that determines the failure of IGBT modules and affects their reliability is temperature, which means that the junction temperature of IGBT modules is closely related to its reliability. Therefore, a novel junction temperature extraction technology of IGBT module for on-line reliability state detection is proposed in this paper. Apparently different from thermosensitive parameter which is of low measurement accuracy and poor real-time performance, the IGBT turn-off loss parameter has the advantages of quick response, easy detection and no damage to IGBT structure. This paper describes the correlation between junction temperature and turn-off loss principally and establish a 3D database of current, IGBT turn-off loss and temperature at the rated voltage. Through the theoretical analysis, simulation results and physical verification, it can be obviously figured out that this novel technology is feasible and effective.