Analysis and Design of the Integrated Zeta - Flyback Converter as a High-Power-Factor Electronic Ballast for HID Lamps

This paper proposes a Metal Halide lamp electronic ballast based on the integration of Zeta and Flyback converters working in discontinuous conduction mode, in order to provide the ballast power factor correction and to stabilize the lamp current, respectively. The proposed integration besides to reduce the number of ballast components, presents no additional current stress in the shared switch. The lamp is supplied with a low frequency square waveform to avoid the acoustic resonance phenomenon. The proposed topology has been implemented and validated by experimental results.