Enhanced Single-Phase Full-Bridge Inverter with Minimal Low-Frequency Current Ripple

This paper describes a single-phase full-bridge inverter that possesses limited current ripple at the dc link while providing a sinusoidal square power at the ac output. This is achieved through the addition of an extra pair of switches and complementary control for the full-bridge inverter. The extra switches operate to prevent the double-line frequency ripple current from flowing into the input of the inverter. In doing so, the pulsation component of the sinusoidal square output power is confined to flow between the output capacitors and the load. Thus, the dc link input only supplies the dc component of the output power. Simulation and experimental results validating the proposed solution are presented.