Electronic ballast for high pressure sodium lamp based on charge pump power factor correction technique

This paper investigates the application of continuous input current charge pump power factor correction (CIC-CPPFC) techniques in electronic ballast. Comparing with traditional two-stage electronic ballast, it has fewer components and lower cost. The laboratory prototype of CIC-CPPFC electronic ballast for 50 W HPS lamp is designed and tested in this paper. Experiment results verify that the single-stage electronic ballast can not only ignite HPS lamp with variable frequency, it can also hold constant power when the input voltage varies in a wide range. It has various malfunctions protection function including open circuit, short circuit, or hot lamps. During the starting-up period, the protection circuit will block the half-bridge inverter for a long period if the lamp in hot state. After the protection time, the lamp isn´t in hot state, and it will be turned on again. In this paper, more than 0.99 power factor and less than 11% THD can be achieved