CONTROLLER FOR OPERATING A HIGH PRESSURE GAS DISCHARGE LAMP

摘要

A controller for operating a gas discharge lamp to detect arc instabilities includes operating the lamp at a plurality of operating frequencies and recurrently sensing an electric lamp parameter to determine a stability factor for each frequency. While operating at each frequency, a deviation in the sensed electrical parameter is determined, which is used to calculate the stability factor, which is inversely proportional to the determined deviation. The lamp is operated for longer durations at frequencies having higher stability factors than at frequencies having lower stability factors.