具有低输出纹波的双电感复用无桥buck-boost PFC变换器

Low output ripple single-stage bridgeless buck-boost PFC converter with dual-inductor multiplexing

单相buck-boost功率因数校正(PFC)变换器凭借高功率因数(PF)与升降压的输出特性广泛应用于小功率非隔离LED场合(≤25 W),但是随着双碳政策的推行,需要进一步提升变换器性能。因此提出一种双电感复用的单级无桥buck-boost变换器,其双电感分别交替工作于电感电流不连续导通模式(DCM)与连续导通模态(CCM)。工作于CCM的电感可以与电容构成LC滤波电路减小输出纹波,工作于DCM的电感可以使变换器仍然采用单电流闭环控制实现接近于1的PF与输出调节。此外,所提出的变换器仍然可以采用含谐波注入的控制,进一步降低输出电流纹波,实现PF与输出电流纹波的权衡。最后,两台实验样机验证了拓扑的可行性和理论分析的正确性。

Single-stage buck-boost power factor correction(PFC)converter featuring high power factor(PF)and step-up/down capabilities,is widely used for low power non-isolated LED applications(≤25 W),however,the launch of the carbon neutralization policy requires the converter to further im-prove performance.A single-stage bridgeless buck-boost converter with dual-inductor multiplexing was proposed with two inductors alternatively operating in discontinuous conduction mode(DCM)and contin-uous conduction mode(CCM).The inductor operating in CCM helps filter switching frequency ripple,and in DCM allows the converter to utilize simple single closed-loop control to achieve output current reg-ulation and near unity PF.Harmonic injection technique is applicable to the proposed converter to further reduce output current ripple.A tradeoff between PF and output current ripple was achieved.Experimen-tal tests verify the topology effectiveness and theoretical correctness.