Use of single stage power factor circuits for compact fluorescent lamps

Abstract

This implementation of single stage power factor circuits for compact fluorescent lamps is provided by cost-effective passive electronic components. Instead of the conventional one which consists of a full bridge rectifier followed by a very large capacitor of hundreds of micro-farad or even a few milli-farad, there exist a basic valley-filled (VF) power factor correction circuit which provides valley voltage about peak of the line voltage. The VF flattens the mains pulsating current to give a quasi-sine wave that greatly increases the power factor correction up to 90% or even higher. If this VF is improved and combined with a valley charge pump circuit, which provide valley current of the input, the PF would be even higher, good enough to meet international standard such as IEC1000-3-2 Class C lighting requirements.