Investigations into LFSW Ballast Induced Instabilities in Ceramic Metal Halide Lamps

A brief study of helical instabilities brought about by the interaction between electronic LFSW ballast and ceramic metal halide lamp parameters is described. Ballast parameters investigated were frequency and rise time while lamp parameters were Hg pressure, discharge tube inner diameter, and electrode diameter. It was found that while the Hg pressure has the greatest impact on the occurrence of instabilities, the commutation frequency and rise time are also of significant importance. A proposed modification to the established theory incorporates the influence of LFSW ballast design parameters. The implications for future ceramic lamp/ballast system developments are discussed