Design Key Points and Multi-Field Simulations for Half Bridge Module of Converter Valve Based on SiC IGBT

There are significant advantages for the application of silicon carbide (SiC) insulated gate bipolar transistor (IGBT) in voltage source converter based high voltage direct current (VSC-HVDC). It can reduce the loss, volume and cost of equipment. In this paper, the design key points of half bridge module of VSC-HVDC converter valve based on series-connected SiC IGBT are described. The design points are summarized and analyzed from the model, gate driver and protection of SiC IGBT to devices in series, and extended to the half bridge module. The complete structure of the half bridge module is designed. Finite element method is used to simulate the multi-field of the half bridge module to obtain the distributions of electric field strength and temperature. The results show that the positions with high electric field strength are mainly concentrated in the inner part of the semiconductor devices and the insulation layers between the busbar. The surface electric field strength of each component is basically less than the breakdown field strength of the corresponding material. Therefore, the half bridge module of converter valve meets the insulation requirement.