Patent ID: 8610410

Claim:
A power converter circuit comprising: a ferrite-core forward type transformer having at least a first primary and a second primary windings and at least one secondary winding; one or more switching circuits for energizing the first primary winding and optionally the second primary winding, said switching circuits comprising at least two switching elements in each circuit; at least one automatic switching device connected in series between a first primary winding and a second primary winding; a current sense circuit connected in series with the first primary winding and the automatic switching device; and a control unit being connected to the automatic switching device, the control unit being configured to operate the automatic switching device based on voltage detected by the control unit in the input of the power converter circuit, and the control unit being connected to the two or more switching elements of the switching circuit for supplying, based on an input current of the current sense circuit, a drive signal to either of the two switching elements so as to minimize dc bias in the ferrite transformer core.