基于自适应峰值电压跟踪控制的减少冗余功率处理无频闪LED驱动器

Double-line-frequency ripple (DLFR) is an instinct problem for single-stage ac-powered LED driver, which causes LED flicker. This paper presents a flicker-free LED driver utilizing adaptive peak voltage tracking (APVT) control, based on the reduced redundant power processing (R2P2) principle. The power stage of the proposed LED driver consists of a single-stage power factor correction (PFC) converter and a type-III R2P2 ripple cancellation circuit (RCC). Compared with the traditional average voltage (AV) control, the proposed APVT control extends the operating voltage range of the LED load and further reduces the processed power of RCC unit, making the processed power of the RCC be closer to the system ripple power. Therefore, it can effectively improve the total efficiency of the power system. Finally, a 70W experimental prototype is built to verify the control strategy. The experimental results show a 2.5% efficiency improvement and a wide LED load range feature compared with traditional AV control.