Electronic Ballast For Metal Halide Lampsbased On MCU Control

The high-intensity-discharge lamps (HID), consisting of a broad range of gas discharge lamps, are notable for their high luminous efficacy, good color rendering and long life. The metal halide lamps (MHL) not only have the best combination of the above properties, but also have the best color rendering. So metal halide lamp is considered the most ideal light source and has a long-range developmental future.So it is time to design the ballast to fit them. Conventional inductance type ballast will be washed out as its so many disadvantages, so electronic ballasts are taking the dominant status in ballast market gradually. In order to overcome some problems in analog control, digital control is becoming a hotspot in the research field of electronic ballast.In this paper, firstly, the lighting principle of high-intensity HID lamps is simply introduced. The metal halide lamp (MHL)’s excellences are summarized. The lighting principle of metal halide lamps and start-up of MHL is achieved based on the discussion of MHL’s structure. Secondly, the condition of electronic ballast market is also analyzed. Thirdly, the thesis synthetically researches the realization scheme of electronic ballast used for MHL by the technical lays of basic topology, control strategy, method for free of acoustic resonance, ignition circuit.At the end of the paper, the digital electronic ballast for 70W mental halide lamps (MHL) is developed successfully on the base of above research. The design process of two stage electronic ballast is presented. Each result is satisfied with the request. All the experiment datum and wave approve the theory analysis completely.