Patent ID: 6370050
Filing Date: 2002-04-09
Classification: H02M,Y02E

Abstract:
An isolated and soft-switched power converter comprising:an isolation transformer; primary and secondary resonant tank circuits coupled back-to-back through the isolation transformer; each resonant tank circuit comprising a pair of resonant capacitances present in series as a resonant leg, a pair of voltage sources connected in series as a tank leg, and a pair of switching devices coupled in series as resonant switches and voltage clamping devices for the resonant leg wherein each of the resonant leg, tank leg, and pair of switching devices and voltage clamping devices are connected in parallel to each other; and a switching controller operable for, gating off the switching devices to cause a resonant voltage to resonant in each resonant leg, the resonant voltage repeatedly obtaining zero-voltage periods for soft-switching a device powered by the converter, and gating on the switching devices during zero-current, zero-voltage conditions for soft-switching the switching devices of each resonant tank circuit.