一种新型LED驱动器的分析与设计

摘要

Traditionally, a capacitor with large value is necessary to reduce the output voltage ripple for DC power supply. Life ex-pectancy of LED converter is always higher than that of the capacitor located in the output of the converter DC power supply. In order to solve this problem, a novel AC LED circuit topology structure is present, and the structure and the circuit parameters calculation are analyzed theoretically. For the structure, fluctuation demand of the DC power for LED converter is not high and capacitor with small value can be used. This results in high life expectancy for the capacitor. Results of simulation and experimental verify the feasibility and correctness of the circuit topology structure and parameter calculations.%传统的具有功率因数校正( power factor correction, PFC)功能的DC输出LED驱动器需要在输出端用容值较大的电解电容来减小输出电流纹波。为解决电解电容的使用寿命短而造成驱动器寿命低于LED寿命的问题,提出一种新型的AC LED拓扑电路结构,理论分析了该拓扑电路结构以及参数的选取。由于该驱动器的输入电压和输出电压都是脉动的,驱动器的输入输出滤波可采用容值较小的薄膜电容,从而提高了驱动器的使用寿命。通过仿真和试验的结果表明,该拓扑电路结构是可行的,其参数的选取是正确的。