A Physics-Based Transient Electrothermal Model of High-Voltage Press-Pack IGBTs Under HVdc Interruption

The wide use of press-pack insulated-gate bipolar transistors (IGBTs) in high-voltage dc (HVdc) applications makes the accurate modeling of high-voltage press-pack IGBTs more urgent. Based on the mechanism of the switching transient, a physics-based electrothermal transient model of the high-voltage press-pack IGBT is proposed. Considering the wider base width of high-voltage IGBTs (HVIGBTs), a transient model of the HVIGBT with buffer layer is presented taking into account the carrier recombination in the base region and the injection level in the buffer layer. Besides, a modified thermal network of press-pack IGBTs is implemented considering the double-sided heat transfer structure. An electrothermal coupling model of high-voltage press-pack IGBTs is then obtained combining the proposed electro and thermal models. Finally, simulations of key dynamic performances of the proposed HVIGBT model match well with the testing results. Furthermore, the HVdc interruption process of a solid breaker with different number of series-connected IGBTs is simulated using the proposed IGBT model and tested. The testing results show good consistency between the simulated and measured voltage and current of the series-connected press-pack IGBTs, which brings strong support to the accurate design of solid breakers in the HVdc transmissions.