中文摘要：

本文通过对具有谐振模式功率因数校正（PFC）的单级AC／DC变换器主电路的仿真、实验和分析，阐明其主要物理量间的内在规律，获得电路工作在非连续电流模式DCM下的条件和各元件参数的设计依据；证明当母线电压降低时，输入功率增大；根据主电路的数学模型，提出对闭环系统进行变频和变占空比控制．

英文摘要：

A single stage AC/DC converter with resonant model PFC is investigated in this paper by mathematical analysis. The results obtained reveal the following facts. The working conditions for the circuit shown in Fig. 1 are derived and can be expressed by the formulas, which can be used to determine the parameters of the circuit. It has been proved that the bus voltage decreases as power input increases, the turn-on time being constant. The optimal controlling strategy for regulating the output voltage is put forward. In order to verify the theoretical analysis conclusions, the simulation results and experimental results are given. The theoretical analysis and math formulas provide a new tool for designing the circuit.