A Family of Electronic Ballasts Integrating Power Factor Correction and Power Control Stages to Supply HPS Lamps

This paper presents a family of high power factor electronic ballasts applied to the public lighting system. Flyback, buck-boost, boost or SEPIC converter is employed in the power factor correction stage, integrated to the power control stage through a single active switch. The use of a half-bridge inverter, to supply the lamp, becomes possible through the employment of a flyback converter in the lamp power control stage. The lamp is supplied in a low frequency voltage square waveform in order to guarantee the safe lamp operation, regarding to the acoustic resonance phenomenon. The presented solutions to supply HPS lamps take the advantage of low cost and simplicity. The shared switch characteristics are analyzed and discussed during this work. A comparative analysis among the presented electronic ballasts is performed