Warm-Up and Steady-State Control of High-Pressure Sodium Lamps Applied to Public Lighting Systems

This paper presents a warm-up and steady-state control method for a 70 W high-pressure sodium (HPS) lamp fed by electronic ballast, in order to replace the still commonly used electromagnetic ballasts and take better advantage of lamp´s useful life and luminous efficacy. Along this work, a reliable electronic ballast topology has been chosen, attending the specified requirements. After, the warm-up and steady-state control algorithms have been developed and a microcontroller has been chosen to perform them. Finally, the circuit has been assembled and experimental results are shown.