Exploring the Electro-Thermal Parameters of Reliable Power Modules: Insulated Gate Bipolar Transistor Junction and Case Temperature

Abstract

In the exploration of new energy sources and the search for a path to sustainable development the reliable operation of wind turbines is of great importance to the stability of power systems. To ensure the stable and reliable operation of the Insulated Gate Bipolar Transistor (IGBT) power module, in this work the influence of changes with aging of different electro-thermal parameters on the junction temperature and the case temperature was studied. Firstly, power thermal cycling tests were performed on the IGBT power module, and the I-V characteristic curve, switching loss and transient thermal impedance are recorded every 1000 power cycles, and then the electrical parameters (saturation voltage drop and switching loss) and the thermal parameters (junction-to-case thermal resistance) of the IGBT are obtained under different aging states. The obtained electro-thermal parameters are substituted into the established electro-thermal coupling model to obtain the junction temperature and the case temperature under different aging states. The degrees of influence of these electro-thermal parameters on the junction temperature and case temperature under different aging states are analyzed by the single variable method. The results show that the changes of the electro-thermal parameters under different aging states affects the junction temperature and the case temperature as follows: (1) Compared with other parameters, the transient thermal impedance has the greatest influence on the junction temperature, which is 60.1%. (2) Compared with other parameters, the switching loss has the greatest influence on the case temperature, which is 79.8%. The result provides a novel method for the junction temperature calculation model and lays a foundation for evaluating the aging state by using the case temperature, which has important theoretical and practical significance for the stable operation of power electronic systems.