摘要
以Buck为基础的单相功率因数校正(power factor correction,PFC)电路,器件电压应力小,输入、输出电流控制能力强;但输入电流存在固有死区,造成输入电流畸变。提出一种双电路模式的单相降压型PFC电路,通过加入1个辅助开关和1个二极管,在传统Buck PFC变换器的输入电流死区时间段,使电路工作于Buck-Boost模式,消除电流死区。对于Buck与Buck-Boost之间的切换控制问题,基于单周期控制,推导出一种非线性控制策略,不同工作模式具有相同的电流控制律,消除了模式切换造成的电流畸变,从而实现单位功率因数。设计了1台开关频率为50 k Hz、输出为100 V/1 A的实验样机,在175~265 V输入电压范围内,输入电流保持较低的总谐波畸变率(total harmonic distortion,THD)。电路实现2个开关管共地,驱动电路设计简单;且不同电路模式采用相同的电流控制律,简化了控制,有利于实际的工程应用。
Buck-type power factor correction(P F C)converters have low voltage stress and strong input and output current control ability,but the input current has naturally dead zones in traditional single-phase Buck-type P F C converter,which leads to high current distortion.A novel Buck PFC converter was proposed?by adding an auxiliary switch and a diode.The dead zones were eliminated when the converter operated in Buck-Boost mode during the dead time.Based on one cycle control,a nonlinear control was deduced to solve the transfer problem between Buck and BuckBoost operating modes.The two operating modes have the same control strategy?which smoothes the modes transfer and nearly unit power factor can be achieved.The circuit operating modes and control strategy were analyzed in d etail verified by experimental results on a50kHz,100V/1A prototype.The total harmonic distortion(THD)of input current keeps low in the input voltage range of175?265V.Both the two switches are grounded,simplifying the driving circuits,and the two operating modes have the same control strategy,which make the proposed converter suitable for practical application.
作者
林维明
刘贤庆
张强
吴南冰
LINWei-ming;LIU Xian-qing;ZHANG Qiang;WU Nan-bing
出处
《电机与控制学报》
EI
CSCD
北大核心
2017年第11期25-32,共8页
Electric Machines and Control
基金
福建省科技厅重大项目(2014H6012)
福建省自然科学基金(2015J01193)
关键词
单相功率因数校正
降压
组合电路
非线性控制
单位功率因数
single-phase power factor correction
step-down
combined circuits
nonlinear control
unity power factor
