Analysis, design, and experimental results of an integrated electronic ballast based on the half-bridge structure

Abstract

This paper presents the analysis, design, and experimental results of a new integrated electronic ballast based on the half-bridge boost rectifier followed by the half-bridge series resonant parallel loaded inverter. The electronic ballast features a high power factor and low harmonics input current. The involved converters share the power switches, reducing costs significantly. The input stage of the ballast works in discontinuous inductor current mode with constant duty cycle and variable switching frequency. It is important to maintain this operating condition in order to get a high power factor. Integrating the power stages results in higher complexity in the control design because a close relationship still exists between the power stages. Within the paper, the operating characteristic is established in order to obtain a design method for the ballast. The obtained method is used to design a laboratory prototype for a 26-watt fluorescent lamp. Some experimental results are included.