Design Of The New100W LED Driver

From the late20th century, the emergence of worldwide energy crisis has forced people to start saving awareness. Lighting electricity using as a large power are doing continuous improvement, from the incandescent lamps, gas discharge lamps to LED lamps. As the latest lighting products, LED rise rapid with energy saving advantages. the voltage characteristic of the LED Determines that the drive of the LED is not a traditional regulated power, requires a constant current output and limited voltage functionality. The function of the drive has a direct relationship to the life of the LED and a series of technical parameters.Paper analyzes the characteristics of LED, studies in-depth of the power factor correction circuits, flyback quasi-resonant circuit, constant current circuit and Electro Magnetic Compatibility(EMC) problem. Based on the theoretical analysis has made a100W LED drive. The design chose two-mode circuit structure, pre-critical mode using boost topology power factor correction circuit, the latter using quasi-resonant flyback circuit topology, constant current control part using double operational amplifier feedback. At the beginning paper introduces the background of the LED industry, LED’s history, light principle, and a series of optical properties. According to the analysis of the characteristics of LED, give the LED driver’s features. Chapter Ⅱ talks about the principle of power factor correction circuit, Introduces the reasons for power factor correction circuits, analysis of the power factor and harmonic concepts and the relationship. Deeply analysis of the passive power factor correction circuit and the popular circuit structure and their own advantages and disadvantages, active power factor correction circuit and its operating mode, comparative analysis of advantages and disadvantages of the various operating modes, Takes FAN7930for an example to demonstrate the critical mode power factor correction circuit’s design methods and the attention for design process. Chapter Ⅲ starts with the soft-switching technology, Introduces the application of soft-switching technology in the flyback circuit flyback quasi-resonant circuit. Compares with the traditional flyback circuits, deeply analysis of the circuit structure and working principle, described several forms clamp snubber circuit in detail, Finally, takes TEA1552for an example to demonstrate the flyback quasi-resonant circuit’s design methods and the attention for design process. Chapter Ⅳ Introduces several ways of the constant current control. Talking from the voltage source series resistance and RC undertension power the LED, analysis the principle of the TL431constant, primary-side feedback, double operational amplifier and Buck constant current control, their advantages and disadvantages, and application occasions. Finally, give the constant current feedback with double operational amplifier circuit’s design process and considerations. Chapter Ⅴ introduces the overall design of the circuit including the efficiency, EMC and reliability issues, from both theory and practice to do an in-depth analysis.Paper designs a100W lamp LED driver and testes the main waveforms of the circuit and EMC. The drive’s output characteristics is steady, overall efficiency is88%, power factor greater than0.98, total harmonic current is11%, EMC testing complete accord with the national standard.