Charge pump high power factor dimming electronic ballast

Voltage source charge pump power factor correction dimming electronic ballast is presented in this paper. The basic charge pump power factor correction principle is first reviewed. Constant lamp power control for the line input variation and crest factor correction technique is then discussed. The lamp power variation is limited to less than ±15% when the line changes ±10% by using lamp current modulation. The crest factor can be minimized by injecting 2^nd order line harmonic in the control loop. The developed dimming electronic ballast was able to be continuously dimmed from 20% to 100% dimming level with higher 0.99 power factor and low DC bus voltage