Power factor correction in electronic ballasts for compact fluorescent lamps

This paper deals with the development and comparison of various types of high power factor electronic ballasts for compact fluorescent lamps (CFL). Electronic ballasts using passive power-factor correction (PFC) techniques and active PFC technique are designed, developed and tested for a 20W CFL. Self-oscillating circuits are used to provide cost effective electronic ballasts for CFL A comparative study is made in terms of ignition voltage and current, ac mains current waveforms, its rms value, total harmonic distortion (THD), crest factor, third harmonics, input power, power-factor and output lumens for general low cost, passive PFC based valley fill and charge clamp topologies and active PFC topology with and without EMC filter based ballasts. The proposed active PFC based ballast with EMC filter results in high level of performance of CFL in terms of power-factor of order of 0.999, THD of ac mains current of 4.7% and its crest factor of 1.42.