Multifunction magnetic device with multiple cores and coils

摘要

A magnetic device includes first and second magnetic cores defining first, second, and middle legs extending between first and second back walls, an air gap defined in the middle leg. First, second, and middle legs, and first and second back walls have a substantially equal width. A first winding is located on the first leg, a second winding located on the second leg, and a third winding located on the middle leg. The magnetic device can be part of an electronic ballast circuit including an AC power source, a positive AC rail, a negative AC rail, a resonant capacitor coupled between the positive and negative AC rails, multiple positive and negative lamp terminals configured to couple to respective gas discharge lamps, and windings on a magnetic device coupled between the positive AC rail and respective positive lamp terminals. The third winding is coupled between AC power source and positive AC rail to define a resonant inductor.

主权项

1. An electronic ballast circuit comprising:
an AC power source; a positive AC rail; a negative AC rail coupled to the AC power source; a resonant circuit including a resonant capacitor coupled between the positive AC rail and the negative AC rail; first and second positive lamp terminals configured to couple to respective gas discharge lamps; first and second negative lamp terminals configured to couple the negative AC rail to respective gas discharge lamps; a magnetic device comprising
first and second magnetic cores each having an E-core configuration, the first and second magnetic cores being substantially aligned to define first, second, and middle legs extending between first and second back walls;the first leg, second leg, middle leg, and first and second back walls having a substantially equal width;a first winding located on the first leg, the first winding coupled between the positive AC rail and the first positive lamp terminal;a second winding located on the second leg, the second winding coupled between the positive AC rail and the second positive lamp terminal;a third winding located on the middle leg, the third winding coupled between the AC power source and the positive AC rail, the third winding configured to define a resonant inductor in the resonant circuit.