一种无电解电容LED驱动电源的研究

Research on an electrolytic capacitor-less driver for LED

分析了三级式功率因数校正(PFC)变换器中储能电容上的电压脉动与其容量的关系,推导了储能电容电压最大值、最小值和平均值与储能电容容量大小的关系并给出了储能电容容量的选取原则。提出增大储能电容电压纹波的方法来大幅度减小储能电容容量,这样可以用薄膜电容代替电解电容来延长电源的寿命。一台90 W的原理样机验证了理论分析的正确性。

A detailed analysis of the relationship between the voltage ripple and the value of the storage capacitor of PFC converter was presented in this paper.The maximum voltage, minimum voltage and average voltage of the storage capacitor as a function of the value of the storage capacitor were derived, and the determination of the value of the storage capacitor was also discussed. The voltage ripple of the storage capacitor was purposely increased to significantly reduce the value of the storage capacitor, so film capacitor could be adopted to replace electrolytic capacitor to increase the lifetime of power supply. The experiment on a 90 W prototype verifies the analyses.