A Power Factor Correction LED Driver With Direct Power Transfer Feature

This article presents an isolated bridgeless single-stage light-emitting diode (LED) driver with high power factor, soft-switching performance, and direct power transfer (DPT) capability. In the proposed circuit topology, a bridgeless boost power factor corrector (PFC) is integrated with an isolated current-driven half-bridge dc/dc converter to achieve a bridgeless single-stage PFC structure. Besides, a direct path is provided using coupled inductors to directly transfer power from the input source to the output. The bridgeless structure and DPT capability result in reduced conduction losses, while the soft-switching operation almost eliminates the switching losses. Therefore, the proposed LED driver benefits from low losses and high efficiency. The proposed LED driver is theoretically analyzed. Also, experimental results for a 150-W prototype supplied from a 120-V/60-Hz utility are presented to verify its performance.