Single-phase voltage source converter with active power decoupling operating in both grid-connected and island modes

The current paper presents a single-phase voltage source converter (VSC) operating in both grid-connected and island modes. The novelty of the proposed system consists in the special control and hardware configuration of the H-bridge VSC that ensure the power decoupling of the double-frequency pulsating power, obtaining a ripple-free DC-link current without using additional power semiconductors. The proposed design, involves adding only two film capacitors at the output of each VSC arm. The system operation, for grid connection and during transfer to and from island mode, is assessed by means of simulation and experimental results.