Optimum Design of Main Circuit for High-Power HID Lamps Electronic Ballast

A novel electronic ballast using dual buck half-bridge inverter is proposed in this paper. The inverter not only eliminates the output waveform distortion problems, but also easily achieves all switches of ZVS state. It is controlled at constant switching frequency by the duty cycle parameter. The IC UCC3305 supplies the high-intensity-discharge (HID) lamp with low-frequency square-wave sources to avoid acoustic resonance. A prototype circuit designed for a 1000-W HID lamp was built and tested to justify the theoretical analysis. Satisfactory performances are obtained from the PSIM simulation and experimental results. The power factor is nearly unity and the THD is less than 5%. The efficiency is approximately 90%.