AC-Link, Single-Phase, Photovoltaic Module Integrated Inverter

This paper discusses a new PV-Module Integrated Inverter (PVMII) topology that is ideally suited for use in single-phase grid-connected PV application. The proposed MII is based on bipolar, AC-link principle, so there are no electrolytic capacitors, and a new power decoupling approach, which can use the minimum value of decoupling capacitance. Hence, a very small, highly reliable film capacitor is cost-effectively used, which also improves dramatically the reliability compared to dc-link topologies with electrolytic capacitors. Further, the proposed MII allows bidirectional power flow; a beneficial feature for advanced grid-support features such as local energy storage and reactive power compensation.