一种单级串联型N路输出电流独立控制LED驱动电源  

Single-stage Series-type LED Driver with Independent Control of N-channel Output Currents

作　　者：黄健 罗全明[1] 何青青 周雒维[1] HUANG Jian;LUO Quanming;HE Qingqing;ZHOU Luowei(School of Electrical Engineering,Chongqing University,Chongqing 400044,Chin)

机构地区：[1]重庆大学电气工程学院,重庆400044

出　　处：《电源学报》2018年第4期99-106,共8页Journal of Power Supply

基　　金：国家自然科学基金资助项目(51577019)~~

摘　　要：在多彩LED环境照明、LED投影等应用场合,多路输出电流需要实现独立控制。针对此应用目标,提出一种单级串联型N路输出电流独立控制的LED驱动电源,单级结构保证自动实现功率因数校正功能,N-1个由开关管、二极管和输出滤波电容组成的有源输出单元AOU(active output unit)和1个仅由二极管和输出滤波电容组成的无源输出单元POU(passive output unit)串联构成串联型N路输出结构,通过对N路输出电流采样并进行闭环控制,保证各开关管工作占空比不同,即可实现N路输出电流独立控制。以3路输出为例,详细分析了驱动电源的工作原理及其闭环系统控制方法,并搭建了1台总输出功率为120 W的实验样机,实验结果验证了理论分析的正确性。In application scenarios such as multi-color LED ambient lighting and LED projection, multiple output currents always need to be controlled independently. For this purpose, a single-stage series-type LED driver with independent control of N-channel output currents is proposed in this paper, whose single-stage structure can ensure the realization of the function of power factor correction automatically. N-1 active output units（AOUs）, each of which is made up of power switches, diodes, and one output filter capacitor, and one passive output unit（POU）, which is made of diodes and one output filter capacitor, are series-connected to form a series-type structure with N-channel outputs. By sampling each output current from the N channels to form a closed-loop control system, N-channel output currents can be independently controlled owing to different duty cycles of each power switch. By taking a LED driver with 3-channel outputs as an example, the operating principle and the closed-loop control method for the proposed LED driver are analyzed in detail. Finally, a 120 W experimental prototype was built, and the experimental results verified the theoretical analysis.

关 键 词：LED驱动电源 N路输出 电流独立控制 有源输出单元 无源输出单元 

分 类 号：TM46[电气工程—电器]