A More Efficient Single-Phase Single-Inductor Electrolytic Capacitor-Less Converter with Power Decoupling and Automatic PFC Capability

Reducing power transmission is a new trend to increasing the whole efficiency. Meanwhile, the presence or absence of electrolytic capacitor (E-cap) is another important criterion for judging the performance of LED drivers. Based on this, a new single-stage AC/DC converter is proposed in this paper, which demands fewer power semiconductors compared to previous works due to the magnetic integration technology and the time-division multiplexing of devices, thus lower cost and higher efficiency is achieved. And, the power flow of decoupling circuit is further optimized, where most of the energy is designed to transfer directly to the load, reducing the intermediate link and simultaneously employing the film capacitor. Besides, a simple automatic PFC scheme is presented, where near perfect power factor is obtained. Finally, all the superior performances of proposed LED driver are verified under PSIM simulation platform.