Junction Temperature Estimation Method for Press-pack IGBTs Using Double-side Thermal Resistance Network Model

Due to the asymmetry of the double-side structure of press-pack insulated-gate bipolar transistors (PP IGBTs), the physical significance and calculation method of parameters in the thermal resistance network model are not clear, which brings some challenges to the junction temperature (Tj) estimation method using this model. In this paper, two kinds of double-side thermal resistance network physical models are proposed by calculating the heat flow ratio on both sides and taking the temperature of the top and bottom case as the reference isothermal point. In the single chip packaging and double-side water cooling conditions, the simulation results show that the maximum relative error of the junction temperature estimation of two kinds of models established and the traditional model is −0.13%, 1.21% and −1.42%, respectively. The experiment also verifies that the proposed model has the highest accuracy and a certain range of application for the junction temperature estimation of PP IGBTs.