Patent ID: 7433207

Claim:
A bi-directional converter for converting voltage bi-directionally between a high voltage bus and a low voltage bus, comprising: a switching converter coupled across the high voltage bus, the switching converter comprising first and second switching modules coupled in series across the high voltage bus, a switched node disposed between the switching modules being coupled to an inductor, the inductor coupled to a first capacitor, the connection between the inductor and the first capacitor comprising a mid-voltage bus, the first and second switching modules being controllable so that the switching converter can be operated as a buck converter or a boost converter depending upon the direction of conversion from the high voltage bus to the low voltage bus or vice versa; the mid-voltage bus being coupled to a first full bridge switching circuit comprising two pairs of series coupled switches with switched nodes between each of the pairs of switches be coupled across a first winding of a transformer having a preset turns ratio; and a second full bridge switching circuit comprising two pairs of series coupled switches with switched nodes between each of the pairs of switches being coupled across a second winding of said transformer, said second full bridge switching circuit being coupled to a second capacitor comprising a low voltage node.