Current-source charge-pump power-factor-correction electronic ballast

A current-source charge-pump power-factor-correction (CS-CPPFC) electronic ballast is presented in this paper. Unity-power-factor condition and principle of operation using the CP concept are derived and analyzed. Based on the steady-state analysis, the design considerations are discussed in detail. It is shown that the power switch only deals with the resonant load current, which is the same as in the two-stage approach so that small-current rating devices can be used. The developed CS-CPPFC electronic ballast can save one inductor and has a potentially low cost. The CS-CP electronic ballast with switching frequency modulation to improve crest factor is developed, implemented, and tested. It is shown that 0.99 power factor, 11.3% total harmonic distortion (THD), and 1.54 crest factor can be achieved for 85-W fluorescent lamps.