Optimization of combined voltage-source-current-source charge-pump power-factor-correction electronic ballast

Abstract

The charge-pump power-factor-correction (CPPFC) electronic ballast has become attractive for ballasting fluorescent lamps because it employs a charging capacitor instead of a bulky inductor to achieve the power-factor-correction. Several topologies have been previously proposed. Among them, the combined voltage-source-current-source (VSCS) CPPFC electronic ballast with improved-crest-factor (ICF) has a better overall performance. However, the operation principle is not straightforward, making the subsequent design difficult. In this paper, circuit derivation and mathematical analysis are first presented, then a design guideline is proposed, and finally, electronic ballast with two 45-watt fluorescent lamps is implemented optimally as an example of this topology.