High-power-factor electronic ballast operating in criticalconduction mode

摘要

A high-power factor (HPF) electronic ballast, which exhibits lownswitching losses, is presented in this paper. The proposed topology isnbased on a single power-processing stage, which provides high-frequencynvoltage to fluorescent lamps and HPF to the utility line. The lamps arendriven by a self-oscillating LC parallel resonant power converter ofngreat simplicity and attendant low cost and increased reliability. HPFnis achieved by using a nonconventional boost power converter operatingnin critical conduction mode. Theoretical analysis and experimentalnresults for two 40-W fluorescent lamps operating at 50 kHz from a 127-Vnutility line have been obtained, which demonstrate the high efficiencynand HPF of this electronic ballast