标题: | 可相容TRIAC调光器之无闪烁及高功因LED数位初级侧控制驱动系统 High PF and No Flicker LED Driver System with Digital Primary Side Control that Compatible with TRIAC Dimmer |
作者: | 林智伟 Lin, Chih-Wei 邹应屿 Tzou, Ying-Yu 电控工程研究所 |
关键字: | LED驱动电路;返驰式转换器;TRIAC调光;数位式初级侧控制;主动式功率因数修正;LED driver;flyback converter;TRIAC dimmer;digital primary side regulator;active power factor correction |
公开日期: | 2011 |
摘要: | 为了取代即将被淘汰的白炽灯调光系统,TRIAC调光器与LED灯泡的结合为近年来各大厂商努力研发的方向,然而此结合存在着许多的问题,例如:TRIAC的维持电流(Holding current)、因被动元件而产生的电流震荡以及在TRIAC调光位置固定下导通角度会随着市电波动影响等都会使LED灯泡的发光稳定性下降。为了克服上述所提出之问题,本文加入被动阻尼器及数位式输入电压补偿机制来改善震荡电流及调光命令受市电扰动影响之问题。 除了针对TRIAC调光器之问题做改善之外,本文为了提高隔离型LED灯泡之竞争力加入了初级侧控制架构,不但大幅简化外部所需之零件数,并可提高整体电路可靠度及降低成本。估测次级侧二极体平均电流可由初级侧峰值电流及二极体导通时间计算出,而二极体导通时间侦测机制上利用辅助绕阻电压的零交越讯号计算时间长度并对不连续导通模式下磁化电感去磁区间做震荡时间侦测且补偿。 在效能方面为了符合功率因数之规范,本文加入主动式功因修正控制并采用数位类比混合式控制架构,外回路为数位控制包含初级侧电流控制及TRIAC电流命令侦测,而内回路为类比峰值电流控制。最后实验部分加入LT3799及白炽灯做为比较对象,针对一可调光LED驱动系统相关效能曲线做比较并分析其差异性及讨论。 In order to replace incandescent lamp dimming system, LED light bulbs with TRIAC dimmer is one of main stream research in recent years, but there are many problems for combination of LED and TRIAC, such as: TRIAC’s holding current、current resonant generated by passive components, and the conduction angle fluctuated with line voltage. To overcome the above problems, the passive damper and digital input voltage compensation for dimming command are proposed to improve the problems mentioned above. The primary-side sensing architecture is adopted in this thesis, not only greatly simplifies the number of external components required, and improves overall circuit reliability and low costs. The output average current can be estimated by primary side peak current and the secondary side diode conduction time, the secondary side diode conduction time detection mechanism join the resonant time of demagnetization interval compensation that can increase the estimation accuracy. The thesis adopts active power factor correction control and use digital and analog hybrid control architecture. Finally, the experiment results of the thesis proposed will compare with LT3799 and incandescent lamps to analysis the different and discussions. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT079812506 http://hdl.handle.net/11536/46862 |
显示于类别: | Thesis |