Conducted emission reduction technique from wire winding chock for ballast

In the projection product, ballast plays a very important role. The advantages of ballast include small size, lighter in weight and the improved switching frequency. Hence, it can rapidly start the lamp without flickering and increase the lamp life. It may also cause the electromagnetic interference phenomenon while improving the switching frequency. Electromagnetic interference divides into the conducted and radiation emissions. The conducted emission is the major one for ballasts. The conducted emission will injure other electronic equipments within the same electric network. The aim of this research is to reduce the conducted emission through making various types of wire winding chock for ballast. In this study, suitably choose of wire winding chock for ballast to reduce its conducted emission and accord with the limitation of EN55022 Class B conducted will be discussed.