Half-bridge zero-voltage switched multi-resonant converters

Abstract

A half-bridge zero-voltage-switched multi-resonant converter. The converter basically comprises a device for converting an input voltage signal to a DC output signal to be imposed across a load. The device includes input terminals for receiving the input signal and output terminals for imposing the DC output signal across the load. Serially connected first and second switching assemblies are connected in parallel across the input terminals. Each of the first and second switching assemblies includes a transistor switch, a diode and a capacitor all arranged in parallel. The device further includes a transformer having a primary winding and serially connected first and second secondary windings. A first rectifier in parallel with a first resonant capacitor is used to connect the first secondary winding across the output terminals. Circuitry is provided for connecting the primary winding of the transformer to the input terminals and to the serial connection between the first and second switching assemblies. In order to complete the zero-voltage-switched multi-resonant converter for off-line use, a resonant circuit is formed with the first and second resonant capacitors and the total inductance of the primary winding of the transformer.