High frequency power supply system driving nonlinear loads

Tubular fluorescent lamps used in industrial printing machines are powered by conventional transformers. These configurations have severe disadvantages concerning maintenance, space requirements and energy efficiency. In this paper a system is presented which eliminates these disadvantages and makes it possible to control the luminous flux of the fluorescent lamp over a wide range. The power supply system requires approximately the same space as a standard PC-switching power supply device of about 300 W. The applied concepts are explained and accompanied by practical results. The supply is based on a high frequency DC-AC bridge converter.