HVIGBT Physical Model Analysis During Transient

The insulated gate bipolar transistor (IGBT) physical models are studied in details. The difference between low-voltage IGBT (LVIGBT) and high-voltage IGBT (HVIGBT) is analyzed and the shortage of the LVIGBT model used for HVIGBT is discussed. The physical model considering the effect of carrier concentrate on excess carrier lifetime is established for HVIGBT. The HVIGBT transient model is presented with different excess carrier lifetime in the base. The new description of steady-state U-I characteristics is also obtained with numerical method. The test experiment was performed in a Buck converter using 6500 V HVIGBT with different bus voltage and load current. The accuracy of the transient model of HVIGBT is verified by experiment and simulation results. The verification of some key parameters to describe the external characteristics is also given in the paper.