An improved electronic ballast for the fluorescent lamps

The ''charge pump" electronic ballast circuit, which employs a charging capacitor and a high frequency ac source to implement the power factor correction (PFC), has become an attractive topology for ballasting the fluorescent lamps because it eliminates the use of a bulky boost inductor. But the high voltage stress on the semiconductor devices at light load conditions, the high total harmonic distortion (THO) of the line current, and the poor crest factor ( CF) of the lamp current in this circuit make it difficult to manufacture this circuit into a cost-effective ballast product. This thesis analyzes the problems associated with the "charge pump" electronic ballast, and proposes several innovative methods to solve the problems, resulting in a high performance and cost-effective technology.