Research On Electronic Ballasts For Low-power High-intensity Discharge Lamps

The electronic ballast(EB) for high intensity gas discharge lamp(HID) is an important energy-saving product, and with the implementation of the green lighting project, it gains ever-increasing worldwide attention in recent years. Many scholars at home and abroad have done great deal of research work in this area. How to lower the cost of the EB with high power factor, high efficiency and high stability is the key technology need to be resolved currently.In this paper, two new low-power EB are developed on the basis of the research on existing topologies and control methods of the HID electronic ballasts.1.Most of the current high-performance EB adopt a dual-class power structure, however, such topology is relatively complex, leads to higher costs and reduces the conversion efficiency. Therefore, in this paper, a continuous input current charge pump power factor correction (CIC-CPPFC) technology based EB with the single-level power, is proposed on the basis of the study CPPFC technology. The conditions for unity power factor, for soft switching and startup methods are analyzed theoretically, and a theoretical calculation method is given. The experimental study is carried out after the working frequency and the parameters of the circuit are determined, and all performance indicators are reached. The experimental results show that the calculation method is correct.2.In view of the urgent need of vehicle metal halide(MH) lamp in current auto markets, a digital controlled high-performance EB for MH lamp is developed. This kind of ballast is composed of one inductively coupled high-frequency DC-DC boost converter and one low-frequency square wave DC-AC inverter bridge, and it has the characteristics of high efficiency, small switches stress and no acoustic resonance.High-voltage pulse trigger circuit is constructed by rectifier in the main circuit, so MH lamp may be instantaneously quick started. And the process of start and steady work of the lights are well controlled by the method of phased digital control. Experimental results show that the research achievements are real and effective.