Electronic Ballast with Constant Instantaneous Power Output for Fluorescent Lamps without Light Fluctuation

To provide the light output without fluctuation, an electronic ballast is developed to drive fluorescent lamps by constant instantaneous power. The electronic ballast mainly consists of a boost starter to generate a high ignition voltage and then a DC ballasting current. To avoid the damage of cathode filaments due to DC operation of the fluorescent lamp, a full-bridge inverter is used for commutation of the electrodes. The DC ballasting current is converted into an AC square waveform by the full-bridge inverter. Finally, the fluorescent lamp is driven by a constant instantaneous power and results in the light output without fluctuation. Experiments are carried out on a prototype of the electronic ballast designed for the T8-40W fluorescent lamp.