Patent ID: 7869230

Claim:
A resonance circuit for use in an H-bridge DC-DC converter, the resonance circuit comprising: an H-bridge converter, capable of converting unstable DC power into stable DC power, the H-bridge converter comprising: a first active switching element and a second active switching element; a coupled inductor with dual windings capable of storing energy; and a first passive switching element and a second passive switching element; a first resonance circuit, disposed on a buck side of the H-bridge converter for reducing the turn-off loss of the first active switching element, the first resonance circuit comprising: a first inductor, a second inductor, a first auxiliary inductor, a first passive auxiliary switching element, a second passive auxiliary switching element and a first auxiliary capacitor; wherein the second inductor comprises a primary winding and an auxiliary winding; a second resonance circuit, disposed on a boost side of the H-bridge converter for reducing the turn-on loss of the second active switching element, the second resonance circuit comprising: a second auxiliary inductor, a third active switching element, a first auxiliary inductor, the first passive auxiliary switching element, a third capacitor, a fourth capacitor and a second auxiliary capacitor; and wherein the first resonance circuit and the second resonance circuit are connected using: the first auxiliary capacitor being connected in series to the first passive auxiliary switching element connected in parallel to the first active switching element; and the negative end of the second passive auxiliary switching element being connected in series to the joint of the first auxiliary capacitor and the first auxiliary passive switching element through the first auxiliary inductor and the auxiliary winding of a second inductor while the positive end of the second auxiliary passive switching element being connected to the negative end of an input power.