A New High Efficiency HID Electronic Ballast

摘要

This paper presents analysis and design of a modifiednsynchronous buck converter used as an intermediate stage of a threestagenhigh-intensity discharge (HID) electronic ballast. In order tonimprove the efficiency of the electronic ballast, a synchronous bucknconverter operating in a new critical continuous conduction mode isnproposed. Unlike a standard buck converter which is typically used asnan intermediate stage of HID ballasts, in the proposed topology thensoft-switching is achieved which significantly improves the efficiency ofnthe three-stage high-intensity discharge electronic ballast. The modifiednsynchronous buck converter and a two-loop controller are analyzednand implemented for a 400W HID lamp. Experimental results of an400W HID electronic ballast operating in three modes of operation:nopen circuit (OCM), short circuit (SCM), and power control mode (PCM)nis presented.