Research And Design On Signal Stage Power Factor Correction Power Of LED

With the persistently rising in price of energy resources, it is meaningful to use higherefficiency, lower cost light source. For it's advantages of environmental protection, long lifeand high efficiency, the proportion of LED is larger and larger, and the LED driver with thefunction of power factor correction(PFC) is developing as a result. The circuit usingsingle-stage PFC technology is smaller, cheaper, Simpler and more reliable than the two-stage,so a signal-stage power factor correction power supply of LED is designed to meet thepurpose of improving the power factor.Based on the working principle of single-stage PFC, analyzes the advantages anddisadvantages of various converter topologies and applications, and indicates hat flybackconverter is better than the others; By comparing the three operating modes of converter andthe three current control modes, respectively, Continuous Conduction Mode(CCM) andAverage Current Control is selected. The working principle of CCM single-stage PFC flybackconverter is Analyzed in detail and the relationship between the input voltage and the inputcurrent are worked out. In addition,the limit parameter and the output voltage ripple areanalyzed to provide a basis for the design of the main circuit. Based on the above analysis,give the general design method of the CCM single-stage PFC flyback converter. A Prototypewith universal input and 48V/2A output, using the Single Stage Power Factor CorrectionControl IC NCP1652 is designed. By experiment, the circuit works properly, and the powerfactor is 0.98.The circuit basically eliminates the harmonic pollution of the grid to meet theIEC61000-3-2 harmonic standard. Experimental results verify the theoretical analysis iscorrect and feasible, and show that the circuit is practical and valuable, and it has universalsignificance for the single-stage PFC technology.