An electronic ballast with high power factor and low voltage stress

This paper presents a new configuration for an electronic ballast with high power factor for fluorescent lamps. The proposed ballast consists of the integration of a buck-boost converter, used as an input stage to correct the power factor and regulate the voltage on a dc bus, and a resonant half-bridge inverter to drive the lamp. The buck-boost converter operates at a constant frequency and constant duty cycle in a discontinuous conduction mode during all input cycles.