A Decoupled Low-Frequency Ripple Cancellation Method for High-Power LED Driver circuits

摘要

Now a days, flickering in LED is a challenge for researchers as it has adverse effect on human health. Using electrolytic capacitor was the initial solution for flickering. However, electrolytic capacitors are not preferred for LED driver owing to short lifetime and more prone to fault. There exists several ripple cancellation (RC) techniques discussed in literature. However, they suffer from complex control structures and high stress across the switches. In this regard, this paper proposes a novel series current RC method to eliminate the double line low frequency ripple and also have removed the electrolytic capacitor. The key features of the proposed RC method include UPF operation throughout without any external circuitry by using the multilevel converter, simple control and reduced smoothing capacitance value. The validation of the proposed method in simulation has been presented.