A high power factor ballast using a single switch with both power stages integrated

This paper presents a high power factor electronic ballast used to startup fluorescent lamps employing a single power stage and a single-switch. This topology was obtained combining of a Boost converter and a new inverter topology with coupled inductors. The use of a single active switch reduces the number of components used in the control and power circuits. The equations used for designing the proposed reactor and for choosing the semiconductor devices are presented. A prototype operating at 50kHz was built and used to startup 40-W fluorescent lamps.