Single-ended soft-switching electronic ballast with unity power factor

A soft-switching single-ended AC/AC converter that is suitable for a high-frequency electronic lamp ballast is described. In spite of its simplicity, the converter offers excellent performance with regard to load and supply, ensuring high-frequency supply to the lamp, sinusoidal and in-phase supply current, easy control of lamp power, and high efficiency due to soft switching at both turn-on and turn-off. Steady-state operation, control characteristics, and design criteria are discussed, and experimental results for input and output circuit performance, component stress, and efficiency are reported