中文摘要：

为了解决在线式不间断电源系统（UPS）中,采用备用电池供电的升压直流-直流（dc-dc）变流器所存在的输入输出增益比和效率不能兼顾的问题,提出一种新颖的高效高增益升压推挽式隔离型电感-电感-电容（LLC）软开关串联谐振变流器.该变流器中的所有功率半导体元件均能实现软开关.通过工作在升压（Boost）模式下获得的高输入输出增益可有效减少变压器匝比,提高转换效率.内部驱动电路因基于推挽电路的结构而得以简化,该变流器适用于UPS电源系统中备用电池的能量升压转换场合.描述该变流器的工作原理和电路特性后,给出其拓扑的各种变化及变形结构,并用一台容量为600V·A的双路输出样机验证了该变流器的有效性和实用性.

英文摘要：

To overcome the limitation that the battery sourcing step-up dc-dc converters can not possess the merits of hicgh efficiency and highdc gain both in the application of back-up mode for online uninterrupted power supply（UPS）systems,a novel step-up push-pull type isolated inductor-inductor-capacitor（LLC） series resonant dc-dc converter was proposed.This converter possessed the soft-switching advantage for all power semiconductors.When operated under Boost mode,the proposed converter obtained a high dc gain,which reduced the transformer＇s turn-ratio to improve conversion efficiency.The inside low-side gate driving circuit was also simplified because of inherit of the push-pull topology.Therefore,the proposed converter is quite suitable for the step-up conversion under battery souring mode in UPS systems.The detail operation principles,characteristics and topdogy variations of the conveter were presented.the validity and applicability were also verified by a 600V·A dual outputs prototype.