A High Power Factor LED Driver with Intrinsic Current Balancing Capability

The research proposed a novel LED driver with the functions of power-factor correction (PFC) and current balancing. A flyback converter Class-D series resonant were integrated by sharing an active switch to form single-stage circuit topology. played role PFC circuit. component parameters designed make operate at discontinuous-conduction mode (DCM). In this way, input line can be sinusoidal, resulting in near unity power factor low total harmonic distortion (THDi). was connected differential-mode transformer turns ratio 1 drive four strings. strings will automatically evenly balanced using 1:1 transformer. This article analyzed different modes operation detail, derived mathematical equations components. Finally, 72-W prototype implemented tested. satisfactory performance has verified feasibility driver.