一种具有快速动态响应的新型数字PFC控制器

A New Digital Boost PFC Controller with Fast Dynamic Response

本文设计了一款新型基于DCM工作模式的全数字PFC控制器,主控制采用了分段自适应PI控制策略,可根据负载、输入电压等的变化实时改变控制参数,不但能够提高系统的抗扰动能力,而且使得系统具有快速的动态响应性能。辅助控制引入了一种新颖的启动电流尖峰抑制策略,该策略基于工作模式控制,通过限制最大占空比使得电路工作在电流断续模式,在充分抑制启动电流尖峰的同时提供了足够的能量,保证了系统快速启动。实验结果表明,所设计的数字PFC系统在输入电压110~230V、最大输出功率140W的测试环境下,最大PF值为0.995 8,最大效率为95.68%。测试中系统启动时间均小于10个工频周期,无电压超调及启动浪涌电流。负载切换的响应时间最大179ms,最小21ms,过冲电压10%~20%。

A new discontinuous conduction mode(DCM) digital power factor coorection(PFC)controller is presented in this paper. The main control employs segmented self-adaptive PI control strategy that can adjust control parameters in real time according to the changes of load and input voltages, to improve system's ability of disturbance rejection and speed up system's dynamic response.Auxiliary control introduces a novel start-up current peak suppression strategy, which, based on operating mode control to limit the maximum duty ratio to make the circuit operates in DCM, can suppress start-up current peak and at the same time can serve enough energy, and ensure a fast start-up of the system. The experiment results show that the digital PFC system under the testing environment with 110 ~230V input voltage and 140 W maximum input power, the maximum PF value is 0.995 8 and the maximum efficiency is 95.68%. The start-up time is always less than 10 power frequency cycles during test and there is not voltage overshoot and start-up surge current. The maximum response time of load changing is 179 ms, and the minimum 21 ms. Voltage overshoot is 10%~20%.