Research On LED Driver Based On The PSR Buck-Flyback Single-Stage PFC Converter

With the environmental problems and energy crisis becoming more and more obvious,as one of the main energy consuming systems in the world,general lighting has attracted more and more people's attention.Compared with ordinary lighting products,LED as a clean and efficient environmental protection product has been applied in more areas.However,the LED requires additional DC drive power supply,which provides constant DC.Therefore,the research and design of an efficient,environmental,low cost LED driver has become a hot spot in recent years.The efficiency of power supply products improved to some degree because of the application of single-stage PFC converter,and the control of small and medium power supply is more simple and convenient because of the rise of the primary side regulation(PSR)technique.So,in this paper,we focus on the research of Buck-Flyback single-stage PFC converter LED driver based on PSR.Firstly,several single-stage integrated PFC converters for small and medium power applications are reviewed,and their advantages and disadvantages are simply analyzed and compared.It is pointed out that the Buck-Flyback single-stage PFC converter has better circuit characteristics compared with other single-stage converters,which makes it possible to be used in small and medium power applications.Secondly,for the traditional Buck-Flyback single-stage PFC converter,the constant current can only be realized by the side feedback control method,which brings the disadvantages of complex structure,large volume and high cost.This paper presents a Buck-Flyback single-stage PFC converter LED driver based on PSR.The circuit topology and the realization of PSR are analyzed,and the circuit characteristics of the converter are studied theoretically.Finally,the circuit model of the converter is simulated by the circuit simulation software.After completing the circuit schematic design and PCB,an experimental prototype with 12 W output power is built.The experimental results show that the prototype has good constant current and high power factor.