Single-stage high-power-factor electronic ballast based on integrated forward half-bridge resonant inverter

A novel single-stage high-power-factor electronic ballast obtained from the integration of a forward DC-to-DC converter and a half-bridge resonant inverter is evaluated in this paper. The forward converter is operated In discontinuous conduction mode and constant frequency providing an input power factor high enough to satisfy present standard requirements. The operation of the proposed ballast is also investigated in detail in this paper. A ballast prototype for a 36 W fluorescent lamp has been both simulated and implemented at the laboratory.