电动汽车SiC MOSFET风冷逆变器的散热器设计

摘要

电动汽车驱动逆变器对功率密度具有很高要求,驱动逆变器的散热设计不仅影响电驱动系统能否可靠运行,同时散热系统的体积也成为制约逆变器功率密度的瓶颈.基于20 kW电动汽车SiC MOSFET风冷逆变器,分析散热器热阻与其几何尺寸的关系,在满足逆变器散热要求的条件下,对散热器风扇个数、散热沟槽数、肋片厚度以及散热器的沟槽长度进行设计,并分别采用热仿真和实验对理论设计进行比对.%An electric vehicle driver inverter has a special request for high power density, and its thermal design directly affects the reliability of the electric driver system; meanwhile, the volume of cooling system also restricts the power density of the inverter. In this paper, based on a 20 kW electric vehicle SiC MOSFET air-cooled inverter, the relationship between the heat sink's thermal resistance and its geometric parameters is analyzed. On the premise of satisfying the cooling requirement of the inverter,the heat sink design,which includes the numbers of fans and heat sink channels, fin thickness and channel length, is performed. Moreover, the theoretical design was compared with thermal simulation and experiments,respectively.