Based On The Llc Resonant Converter Adjustable Light Led Drive Power Supply

With the environmental problems and energy issues are increasingly tense, many countries of the world regard the energy conservation as the most urgent task at the moment. Lighting electricity account for a large proportion of electricity consumption, so more and more attention has been paid to green lighting. LED is an electroluminescent optoelectronic devices, it has many advantages such as long life, high efficiency, energy saving, environmental protection and so on, therefore, it will be an ideal light source to replace the traditional lighting.Strating from the photoelectric characteristics of LED, We analysis the characteristics of the LED driver in detail, Meanwhile, we analysis different topologies which suit for different power level of LED drivers, finally give out the ideal topology for high power LED street lights which is LLC resonant converter.Based on the analysis of the characteristics of LED drivers, we firstly analysed the mostly used topologies of LED drivers and summarized the advantages of a LLC resonant converter, then studied the status of LLC resonant converter in different frequency. Then summed up the way of calculating each parameters of resonant converter based on the FHA. Combined with the requirements of this subject, we also calculated the parameters of the actual resonant converter then make out a power supply to verify the correctness of the theoretical analysis. Lastly, we survived the different dimming ways for LED and designed interface circuit suited for dimmers which used voltage, resistance and PWM signal. In this article, we also designed the main circuit parameters for PFC. By using GMA103A we designed the constant current and constant voltage circuit.At the same time, finished the design of feedback compensation network. In the end, we introduced the design of EMI and reliability of the power supply for LED, meanwhile gived out the actual EMC test waveform.According to the actual LED power supply we designed, we verified the correctness of the theoretical analysis. In the end of this article, we summarized up the entire design and development of this project and made an outlook of the research directions in the future.