Circuit operation of the neutral point type step-down inverter for fluorescence lamp

摘要

In order to clear IEC regulation about harmonics of input current, two-converter type electronic ballast has been developed at the early time, which combined the converter circuit and the inverter circuit. However, this system had many faults. The neutral-points boost converter has been proposed by authors of this paper, which can improve these defaults. And it has been shown that the proposed converter could be applied to the electronic ballast. But some problems that were caused by boost action still remained. Therefore, a new neutral-point type down converter circuit that improves the faults is proposed in this paper. It is shown that proposed converter can be applied to the electronic ballast and a wonderful result can be obtained.