一种超宽电压范围隔离型DC-DC变流器研究  

Research on Extra-wide-voltage-range Isolated DC-DC Converter

作　　者：万新强[1] 倪喜军[2] 骆皓 赖勇[1] 王秀茹[1] 王书征[2] WAN Xinqiang;NI Xijun;LUO Hao;LAI Yong;WANG Xiuru;WANG Shuzheng(State Grid Suqian Power Supply Company,Suqian 223800,China;School of Electric Power Engineering,Nanjing Institute of Technology,Nanjing 211167,China)

机构地区：[1]国网宿迁供电公司,宿迁223800 [2]南京工程学院电力工程学院,南京211167

出　　处：《电源学报》2020年第1期88-95,共8页Journal of Power Supply

基　　金：江苏省重点研发计划资助项目（BE2018130）;江苏省电力有限公司科技资助项目（SGTYHT/16-JS-198）;中国博士后科学基金面上资助项目（2017M621086）;江苏省“六大人才高峰”高层次人才选拔培养资助项目（XNY-021）;南京工程学院科研资助项目（YKJ201522,PTKJ201609）~~

摘　　要：针对不同规格电动汽车的统一充电系统需求,研究2倍以上宽输出电压范围隔离型DC-DC变流器已成为该领域的热点。提出了一种隔离型的LLC串-并联模式变换拓扑及其设计方法,实现0.5~3.0倍的宽输出电压范围,且所有功率器件满足软开关运行。首先,利用半桥变模态控制,获得1.0倍以下电压增益;然后,利用PWM脉冲180°移相实现串-并联快速切换,实现1.0倍或2.0倍电压增益的转换;最后,通过变频结合PWM整流器直流电压调压功能,实现0.5~3.0倍宽电压增益的调节。样机实验结果表明:所提变流器利用上述策略,达到了预期的0.5~3.0倍增益,且实现软开关运行;此外,并联至串联切换过程时间非常短,仅300μs,串联至并联切换过程稍长,但也仅4.5 ms,适用于对电压增益范围要求较宽的应用场合。Recently,due to the demand of a uniform charging system for electric vehicles(EVs)of different specifi-cations,the isolated DC-DC converter with a wide output voltage range and a voltage gain higher than 2 has become a hot research topic.In this paper,an isolated LLC series-to-parallel conversion topology and its design methodology are proposed,which has a voltage gain of 0.5~3.0.In addition,the operation of soft switching is achieved for all power de-vices.Firstly,this converter can produce a gain of less than 1 under half-bridge mode-switching control.Secondly,it can transform from parallel to series and from series to parallel connection by 180°phase shift through PWM pulse,thus ob-taining a voltage gain between 1.0 and 2.0.Finally,by taking advantage of the variable-frequency control and the DC voltage regulation of PWM rectifier,a wide voltage gain of 0.5~3.0 can be achieved.The experimental results of a proto-type show that the expected voltage gain of 0.5~3.0 can be achieved under the proposed strategy.Meanwhile,all power devices can be operated in soft-switching mode.Furthermore,the transition time between parallel and series mode was very short,i.e.,merely 300μs.Although a little longer time was taken to transform from series to parallel mode,the spe-cific time cost was only 4.5 ms.It is concluded that the novel converter is suitable for application scenarios that require a wide voltage gain range.

关 键 词：宽电压增益 运行模式切换 移相 串-并联连接 

分 类 号：TM46[电气工程—电器]