一种适用于燃料电池车的高升压比DC/DC变换器

A High Step-up DC/DC Converter for Fuel Cell Electric Vehicle

基于传统的半桥LLC谐振变换器,提出一种适用于输入低压大电流、输出高电压小电流的高升压比DC/DC变换器。变换器初级采用输入倍流结构,次级采用倍压输出结构,相比于传统拓扑,谐振电容电流应力和输出电容电压应力均减小一半。同时变换器增益增加了一倍。详细分析了变换器的工作原理,给出一套可行的设计方法。并基于TMS320F28335实现了变换器的数字控制。最后研制了一台额定频率为200 kHz的500 W样机,满载效率为95.8%。

A high step-up DC/DC converter suitable for low-voltage large-current input and high-voltage small-current output is proposed based on traditional half-bridge LLC resonant converter.After using input current and output voltage doubler.the current stress of resonant capacitor and the voltage stress of output capacitor is reduced by half,meanwhile the converter gain is doubled compared with traditional topology.Operational mechnism is analyzed,a feaxible design method is presented,and digital control is realized based on TMS320F28335.Finally,a 500 W prototype with 200 kHz rated switching frequency is built and the full load efficiency reaches up to 95.8%.