基于SiC和Si器件的燃料电池汽车DC-DC变换器的性能

摘要

为实现燃料电池汽车输出电压、功率的调节与控制,采用了一种交错式双Boost电路的大功率直流—直流(DC-DC)变换器,其中应用了Si和SiC功率器件.基于电路损耗计算和效率仿真手段,对比分析了全SiC[金属—氧化物半导体场效应晶体管(MOSFET)器件、SiC二极管]、SiCMOSFET和Si二极管的混合器件和全硅Si[绝缘栅双极型晶体管(IGBT)器件、Si二极管]的变换器在电路损耗.结果表明:Si IGBT的开通和关断损耗约是SiC MOSFET的3倍和10倍,在不同工况下,全SiC变换器的转换效率比全Si变换器高1％～3.1％.因而,SiC功率器件在大功率DC-DC变换器的应用中,能够提高功率密度、可靠性和动力系统工作效率.%The performances in circuit loss of an interleaved dual Boost high power derect-curent to derectcurent (DC-DC) converters were analyzed by using Si devices or/and SiC devices in a fuel cell vehicle to regulate and control the output voltage and output power.The circuit losses and efficiency in the whole SiC devices (i.e.SiC Metal-Oxide-Semiconductor Field-Effect Transistor,MSOFET and SiC diode) converter,hybrid devices (i.e.SiC MOSFET and Si diode) converter and the whole Si devices (i.e.Si Insulated Gate Bipolar Transistor,IGBT and Si diode) converter were compared base on circuit loss numerical calculation and efficiency simulation.The results show that the Si IGBT losses are 3 times for switching on and 10 times for switching off as that of SiC MOSFET and the efficiencies of All-SiC devices are 1％～3.1％ higher than All-Si devices in different conditions.Therefore,the SiC devices can improve the power density,reliability and efficiency of the power system for high power DC-DC converters.