Full bridge DC-DC converters

摘要

A full bridge DC-DC converter has four switching devices in two switching legs each of two devices connected in series between two supply voltage terminals, junction points of the legs being connected to a primary winding of a transformer, from a secondary winding of which an output voltage of the converter is derived by rectifying and filtering. The output voltage is regulated by phase shift control of the switching devices. Zero voltage switching (ZVS) of the switching devices under potentially all converter load conditions is provided by snubber capacitors, connected in parallel with the switching devices, in conjunction with two inductors each connected between the junction point of a respective one of the switching legs and a point at a voltage midway between the voltages of the supply voltage terminals, which can be provided by a capacitive voltage divider between the supply voltage terminals. The inductors typically have different inductances, and one of the inductors may be omitted.