Single-Phase Voltage Source Inverter with Active Power Decoupling Based on Buck-Boost Converter

This paper presents a single-phase bridge inverter with the capability of solving the second-order ripple power issue. In this topology, the inherent ripple power in the single-phase inverter is eliminated by directly controlling the ripple current with an additional power decoupling circuit based on a bidirectional buck-boost converter. Therefore, the required dc-link capacitance can be significantly reduced. The operation principle and control strategy of the proposed topology is analyzed and its power decoupling capability is compared with two related topologies in literature. Also, the broken down problem of one of the capacitors in the proposed topology is also analyzed. Simulation results verify the validity of the proposed topology and control algorithm with the expected power decoupling function.