.380v/600w And New Two Low Frequency Square Wave Hid Lamp Electronic Ballast

As the development of Green Lighting Project, the high intensity discharge (HID) lamp is drawing close attention due to its energy saving and high lighting efficiency. Therefore the development of the drive circuit of the lamp, namely ballast has become an important research point. Because of the excellence in energy saving, light weight, etc., electronic ballast will gradually take the place of traditional electromagnetic (EM) ballast.A series of problems in the latest developments of electronic ballast are discussed in the thesis based on the detail design of the 600W electronic ballast provided with 380V high voltage input and the research of a novel low-frequency electronic ballast.At the beginning of the thesis, characteristics of different lighting sources, especially the electronic characteristics of HID lamps, are introduced. The operation principles, superiority and developments of electronic ballast are also presented.In order to understand the lamp's negative incremental impedance of characteristics and analyze the stability of Ballast/Lamp system clearly, the low-frequency ballast system stability with closed loop are analyzed based on the HID lamp frequency-domain model in Chapter II.Detail design process of a 380V/600W high frequency electronic ballast for High Pressure Sodium lamp is given in Chapter III. It's verified by simulation and experiment.There are acoustic resonance phenomena in HID lamps when driven at high frequency, which prohibits the developments of electronic ballast of HID lamps. Chapter IV investigates the mechanism of acoustic resonance, its effects and its characteristics. Finally all kinds of methods to eliminate acoustic resonance are reviewed.At the end of the thesis, the review on the developments of low-frequency square wave electronic ballast is given. Then a novel two-stage low-frequency square wave electronic ballast for HID lamps is proposed with detailed proposed circuit analysis and control circuit description. Finally simulation and experimental results are provided to verify its superiority.