Design of a loosely coupled transfomer loaded series-parallel class-DE ZVS inverter

This paper presents a detailed design procedure for the transformer-based full-bridge Class-DE zero-voltage switching inverter. The circuit topology comprises the series-parallel CLL resonant tank network. The characteristics of the CLL resonant tank circuit in the presence of a loosely-coupled transformer are discussed. The expressions for the components, which are required to design the inverter to achieve zero-derivative switching (ZDS) condition are derived. A laboratory prototype of the transformer-based full-bridge Class-DE inverter with an input voltage 11 V, output power 10 W, switching frequency 500 kHz, and coupling coefficient 0.44 was designed, built, and tested. Validation of the theoretical predictions were performed using simulation and experimental results.