A Combined Centralized/Decentralized Voltage Regulation Method for PV Inverters in LV Distribution Networks

A combined centralized/decentralized reactive power control strategy for PV systems connected to LV distribution networks is discussed in the present paper. The proposed solution is based on a centralized control performed by the Distribution System Operator (DSO) coordinated with a local/decentralized control operated at the PV converter level. The proposed strategy ensures high performance in terms of proper voltage regulation both in the overall network (considering the voltage in every node) and locally (controlling the voltage at the point of common coupling of every PV system). The presented method aims to provide a viable solution towards the fulfillment of a real DG integration into the distribution network and the achievement of a LV "active" network. A radial distribution topology, commonly used in LV networks, is selected to evaluate the proposed strategy. Results are also included in the paper.