为了保证电网供电质量及可靠性，降低能量损耗，提高能源利用效率，功率因数校正技术被广泛使用于电力电子系统，以降低谐波污染和提高电网输入功率因数。模拟控制方案所固有的缺陷，限制其发展及应用前景，数字控制方案所具有的优势使其正成为功率因数校正技术领域研究和应用热点，然而目前研究中整体存在难以实现系统全工作范围内高功率因数值、控制电路动态调节性能偏低等问题。本课题将系统研究数字PFC系统调节机理，从系统功率级拓扑电路中关键器件入手，提取关键寄生参数，基于带非线性寄生参数差分方程组，推导建立功率级拓扑电路精确数学模型；分析数字控制采样量化和控制时延在系统时域及频域中影响，进而建立数字控制电路精确数学模型；以数字PFC系统整体环路数学模型为基础，设计并优化数字控制电路架构和控制算法，并基于实际电路结构设计目标预测补偿算法，降低实时调节误差，最终提高数字PFC系统全工作范围内功率因数值和动态调节性能。

In order to guarantee the quality and reliability of power supply, reduce the energy loss, improve the efficiency of energy utilization, the power factor correction technology has been widely used in power electronic system, to reduce the harmonic pollution and improve the input power factor of power grid. The development and application prospects of the analog control scheme have been restricted, owing to its inherent defects. The digital control scheme has been the hotspot of research and application of power factor correction, owing to its particular advantages. However, it is difficult to achieve high power factor and excellent dynamic response during the whole working range. The digital PFC system adjustment mechanism will be studied in the topic. Focusing on the key device in the topology circuit of digital PFC system, the key parasitic parameters of device will be extracted. Based on the differential equations with nonlinear parasitic parameters, the accurate mathematical model of power level topology circuit will be established. The influence of sample quantization and control time delay should be analyzed both in the time domain and frequency domain, and the accurate mathematical model of the whole digital control circuit will be also established. The digital control circuit structure and control algorithm will be studied and optimized based on the accurate mathematical model of the whole digital PFC system. Meanwhile, the digital target-predicted compensation algorithm will be applied to reduce the adjusting error. Based on the above study, the aim of the topic is to achieve high power factor and excellent dynamic response for digital PFC system during the whole working range.