Design Of150W LED Driver Power Supply Without Electrolytic Capacitors

LED has the advantages of energy saving, environmental protection, long service life, iscalled a new generation of green light source, and also makes the LED lighting industry hasbecome the focus of attention of green industry. The volt ampere characteristic of LED determinesthe traditional regulated power supply can’t for the power supply, and need LED drive withlimited pressure function and constant current output. The life of LED lamps depends on theservice life of the LED driver, and the life of the LED driver has a lot to contact with the lifeof the electrolytic capacitor. Due to the influence of factors,such as environmentaltemperature, voltage, ripple current, frequency.The service life of electrolytic capacitors onlythousands hours, and the life of the LED light source can reach tens of thousands hours.Because the life of electrolytic capacitors and the life of the LED light source do not match,greatly reduce the life of the LED drive power supply. In order to solve the LED drive power lifeproblems, this paper learn that remove or change for other capacitance, to solve the problem ofshort life of LED drive power supply.In order to achieve no electrolytic capacitor LED drive power supply through this designuse CBB capacitors instead of the electrolytic capacitors. But large ripple can occur withoutelectrolytic capacitor. The capacitance of CBB capacitors has no large of electrolyticcapacitors, and in the PFC topology (Boost circuit). Due to its characteristics of itself, needsone big electrolytic capacitor to weaken the ripple. In order to solve this problem, the designadopts the method of third harmonic injection. The choice of MCU is PIC16F1939MCU. Toachieve no electrolytic capacitor LED drive power supply. This design adopts the topologicalstructure of the boost and dual switch forward, the PFC circuit uses the chip of L6563, DC/DCcircuit use the UC3844and IR2110chip.In this paper, on the basis of research on LED driving power supply, realize a LED driveof150W no electrolytic capacitor power supply, the output voltage is36V, output current is4.17A, constant voltage output, for the back of the LED driver chip provide stable directcurrent. The power factor can achieve0.9above, the machine efficiency more than85%.