图腾柱PFC的电感电流过零畸变校正分析

Analysis of Inductor Current Zero-crossing Distortion Correction for Totem-Pole Power FactorCorrector

采用GaN桥臂和SiCMOSFET桥臂的图腾柱功率因数校正器(TP-PFC)具有高效率优点,但是在网压过零附近由于瞬值较低且电压极性转换,引起占比函数突变,如果此时电感取值较大和/或控制器响应较慢,则引起电感电流过零畸变。针对TP-PFC过零附近波形畸变问题,在简述TP-PFC拓扑、数学模型、调制方式以及控制策略基础上,给出了采用PI调节器的双环控制时四种补偿校正方法:变载波幅度法、变控制量法、变控制系数法与变参考信号法,仿真验证了这四种方法能够有效改善电感电流过零附近附近波形质量,明显降低谐波含量和提高功率因数。

Totem pole power factor corrector(PFCS)using GaN bridge and SiC MOSFET bridge has the advantages of high efficiency,but the ratio function changes due to the low transient value and voltage polarity conversion near net voltage zero crossing.If the inductance value is large and/or the controller response is slow,the inductance current zero crossing distortion will be caused.Aiming at the distortion of zero crossing waveform of totem pole PFC,on the basis of brief description of totem pole PFC topology,mathematical model,modulation mode and control strategy,four compensation and correction methods for double-loop control with Pl regulator are given:The variable carrier amplitude method,variable control quantity method,variable control coefficient method and variable reference signal method can effectively improve the waveform quality near the zero crossing of inductor current,significantly reduce the harmonic content and improvethepowerfactor.