The Impact of Gate Resistance of IGBT and SiC MOSFET on the Dynamic Parameters of Si/SiC Hybrid Devices

The insulated gate bipolar transistor (IGBT) and the silicon carbide metal-oxide-semiconductor field-effect transistor (SiC MOSFET) hybrid devices combine the high current-handling capability of IGBTs with the superior high-frequency performance and efficiency of SiC MOSFETs, providing a balanced trade-off between cost and performance compared to fully SiC-based solutions. The gate drive resistances of both the IGBT and the SiC MOSFET play a crucial role in determining their switching speeds and sequences, which in turn impact the overall switching characteristics of the hybrid device. In this paper, a double-pulse simulation circuit for Si/SiC hybrid devices is constructed to investigate the effects of varying gate resistances of the IGBT and SiC MOSFET on the device's switching behavior, and the corresponding influence mechanism is analysed. The findings indicate that by adjusting the gate resistances of the IGBT and SiC MOSFET, it is possible to modify the relative initial switching times and sequences of the devices, thereby affecting key dynamic parameters such as voltage and current overshoot, as well as switching losses. This study provides valuable insights into optimizing the performance of Si/SiC hybrid devices by reducing the risk of dynamic overvoltage and overcurrent, as well as minimizing switching losses. However, further investigations are required to establish an efficient method for selecting appropriate gate resistances.