Development of auxiliary converter based on 1700V/325A full SiC MOSFET for urban rail transit vehicles

摘要

At present, the SiC devices have been widely concerned with the excellent characteristics of low switching losses, which can significantly improve the frequency of power electronic converters, and also have broad application prospects in the field of rail transportation. In this paper, through the establishment of 1500V powered subway auxiliary inverter loss model, the author estimated loss and efficiency of high frequency DC/DC and three-phase inverter under different switching frequency in SiC MOSFET and Si IGBT system, determined the switching frequency for reference in high frequency DC/DC and three-phase inverter, and the analysis shows that the application of SiC MOSFET can reduce the loss of the system, improve the efficiency of the system. Then the author built a simulation model of auxiliary converter model, verified the reliability of SiC filter, setted up a 40kW high frequency DC/DC module with the SiC device selection in this paper, and the module has the efficiency of 97.85% under rated power. The above work provides theoretical support and experimental support for the hardware construction of SiC auxiliary converter.