A unity power factor electronic ballast for HPS lamps, resonant current controlled

The analysis and design of a single-stage electronic ballast with unit power factor are presented in this paper. The proposed single-state ballast is the integration of a boost power converter in DCM and an LCC resonant inverter. The boost semi-stage working in discontinuous conduction mode functions as a power factor corrector and the inverter semi-stage operated above resonance is employed to the lamp ballast. The fundamental approximation is used to design the inverter at steady-state. The proposed lamp ballast can save a controller, reduce size and possibly increase system reliability over a conventional two-stage system.