Robust decentralized PI controllers design for voltage regulation in distribution networks with DG

The presence of Distributed Generators (DGs) in distribution networks may cause voltage fluctuations due to the reverse power flow. To solve this problem the present paper proposes a decentralized approach to regulate the voltage amplitude of the nodes to which the DGs are connected. Each DG is equipped with a PI decentralized controller whose parameters are tuned using a MIMO design. Zero voltage regulation error, robust stability and tolerance to the disconnection of DGs are guaranteed. A IEEE test distribution system with 123 nodes and 15 PVs is simulated to assess the obtained performance. The numerical results demonstrate that the application of the proposed design can help to guarantee robust voltage regulation.