Research Of High Efficiency LED Street Lamp Driver With Full Load Range

High-power LED's advantages include high efficiency, environment friendly, long life and high reliability. So, they are gradually replacing the traditional light sources, such as incandescent and fluorescent, becoming to be a new generation of lighting. However, a highly efficiency driver with entire load range must match the LED street lamp, in order to maximize the lighting's potential of energy saving. The power of High-power LED lights up to 200W, there are no other power supplies meet the requirement of high efficiency except the switching power supply. A highly efficient, highly reliable and high-power LED driver power supply will be developed based on switching converter in this paper, and it will be designed optimal to meet green energy standards. This LED driver can be divided into three levels: with PFC in AC / DC rectifier, resonant soft-switching DC / DC constant voltage output circuit and multi-output DC / DC constant current circuit. Currently, multi-output power constant current circuit mainly Buck topology, the circuit structure is simple and this article will not do a specific analysis. And,This article focuses on research and analysis of the Boost -based Power Factor Correction circuit and half-bridge LLC resonant soft-switching circuit.The main work and the new technologies are putted forward in this paper:(1)establish the equivalent circuit model of LLC, analysis its DC voltage gain and impedance characteristics in-depth, and expose the half-bridge LLC resonant network's inductive maximum voltage gain function;(2) analysis the requirement for main switchs and rectifier diode to realized soft switching and then design the convertor's main switch frequency to improve the supply's efficiency;(3) propose optimal design of the inductance based on considering the Shrinkage Effect and the switching losses;(4) deriver the idealized process of non-ideal transformer, analysis non-ideal transformer's impact for resonant circuit parameter design and the performance,proposed a discrete magnetic components method to design resonant component parameters;(5) design the PFC and LLC resonant converter control circuit based on IC L6563 and IC L6599.Finally, a test is done on the prototype to verify the correctness of the theory.