中文摘要：

提出了一种无源无损缓冲升压功率因数校正（PFC）电路，与传统的PFC电路相比具有许多的优势。首先，主开关上不引入额外的电压和电流应力；其次，为主开关管的软开关提供了很宽的输入和负载变化范围；第三，限制了主开关管上来自反向恢复输出二极管的导通电流。本文详细分析了无源无损缓冲升压功率因数校正（PFC）电路的工作过程，对没有加无源无损缓冲结构和加了无源无损结构之后的两者电路性能特点进行了比较研究。最后，在理论分析的基础上研制一台250W的实验样机，实验结果表明，本文提出的缓冲结构在设计操作范围内可以有效地减少能量的损耗，提高工作效率。

英文摘要：

This paper presents a kind of passive lossIess snubber boost power factor correction （PFC） circuit, Compared with the traditional FFC circuit has many advantages. First of all, it does not introduce extra voltage and current stress on the main switch; Secondly, it provides the switch of soft-switch with wide input and load variation range; Thirdly, it limits the conduction current that coming from recovery output diode on the main switch. This paper has analyzed the working process of the passive lossless snubber boost power factor correction （ PFC ） circuit ,for without passive lossless snubber structure and with passive lossless structure after the two circuit performance characteristics of a comparative study. Finally, based on the theoretical analysis, developed a 250W experimental prototype, the experimental results show that, the buffer structure in the design of operating range can greatly improve work efficiency.