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.