Abstract
An electronic ballast system with emergency lighting features is presented. Especially, the electronic ballast system is relative to a single-stage converter configuration. The electronic ballast system serves as a regular ballast, a regular/emergency ballast, a battery charger or discharger and a power failure detector, fulfilling emergency lighting features. The single-stage converter used in the ballast is an integration of a bi-directional flyback converter and two half-bridge series-resonant parallel-loaded inverters. Unlike conventional approaches, the rectified and filtered input voltage is directly added to a set of battery voltages in the proposed system, so as to reduce the fabrication cost by simplifying the circuit configuration and the number of active switching elements.