In this paper, an electronic ballast was developed to control a 250W metal halide lamp. To avoid acoustic resonance phenomenon, we calculated the acoustic resonance band and determined the driving frequency from 70kHz to 100kHz. Due to the switching loss of MOSFET, many problems are caused in the inverter circuit during lamp lighting, so we reduced the loss by connecting the capacitor that minimizes the magnitude of the impulsive voltage. In this paper, the main point of research is to find the methods to operate the lamp on the rated output power. After detecting the current and the voltage of the lamp, we changed the driving frequency by adjusting the DC voltage level of the VCO input.
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J. Marcos Alonso, Emilio Lopez, Antonio J. Calleja, Javier Ribas, Manuel Rico, 'A Novel Single-Stage Constant-Wattage High-Power-Factor Electronic Ballast' IEEE Transactions on Power Electronics. VOL. 46, NO. 6, 1148-1158, December 1999
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J.W. Denneman, 'Acoustic resonances in high frequency operated low watt metal halide lamps' Philips J. of research, Vol. 38, 1983
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Stockton, R.E. 'Compatibility Between Lamp, Ballast and Igniter In High Pressure Sodium and Metal Halide Lamp Circuits' IPLE LIGHT. J. (GB) VOL.48, NO.1 PP:22-6, 1983
J. Marcos Alonso, Cecilio Blanco, Emilio Lopez, Antonio J. Calleja, Manuel Rico, 'Analysis, Design, and Optimization of the LCC Resonant Inverter as High-Intensity Discharge Lamp Ballast' IEEE Transactions on Power Electronics. VOL. 13, NO. 3, 573-585, May 1998