一种基于重复控制的无电解电容LED驱动电源

An Electrolytic Capacitor-less LED Driver Based on Repetitive Control

LED驱动电源大多使用了容量较大的电解电容作为储能滤波元件,然而其平均寿命远低于LED器件,限制了驱动电源的使用寿命和电源功率的进一步提升。针对该问题,设计了一种基于重复控制的无电解电容LED驱动电源,采用Boost功率因数校正电路,提高输入功率因数,此外,利用Buck/Boost变换器进行升压储能,并结合周期性重复控制算法,对储能实施调节,从而达到输入脉动功率与输出恒定功率之间的平衡,使负载LED获得恒定电流。由于没有采用大容量的电解电容,因而提高了LED驱动电源的使用寿命。最后,搭建了一套基于重复控制算法的无电解电容LED驱动电源,测得输入功率因数为0.97,恒定输出的电流纹波系数为3%。

Electrolytic capacitors with large capacity are often used as energy storage and filter elements for LED driver.However,its average life is far lower than that of LED devices,which will restrict the lifetime of driver and the further increment of power.In order to solve this problem,an electrolytic capacitor-less LED driver based on repetitive control was designed.Boost power factor correction circuit was used to improve the power factor of input.In addition,Buck/Boost converter was adopted to boost voltage for energy storage,combining with periodic repetitive control algorithm to adjust the energy storage,so as to achieve the balance between pulsating power of input and constant power of output,and obtain constant output current for LED loads.Since no electrolytic capacitor with large capacity was used,the lifetime of the LED driver was prolonged.Finally,a set of LED driver without electrolytic capacitor based on repetitive control algorithm was built.The test results show that power factor of the input is 0.97 and the ripple coefficient of direct current output is 3%.