Abstract: This paper presents a close loop three stages Electronic Ballast for Metal Halide (MH) High Intensity Discharge (HID) Lamps. Normally Electronic Ballast consists of power factor correction stage to achieve unity power factor, buck converter to lower the input voltage according to lamp requirement and half bridge inverter to supply the lamp with high frequency sinusoidal voltage and current. LCC resonant tank is used to provide the ignition and normal running requirements of lamp. Since MH lamps are categorised under high intensity discharge lamps, no of electrons in discharge tube reduces as lamp becomes older and lamp resistance increases ultimately. This variation in lamp resistance will affect the lamp power very much that draws the safety issue for end user. To overcome this problem a close loop design of Electronic Ballast is proposed in this paper. So aging protected electronic ballast is modelled ultimately. Proposed circuit is verified with analytical and simulation results.
Keywords: Metal Halide Lamp, Power Electronics Converter, Controller, PSIM.