A decentralized technique based protection and control scheme for distribution network with high DER penetration
This paper presents a decentralized technique based protection and control scheme for the active radial distribution network. A partitioning method for radial distribution network with multi-distributed energy resources is developed considering island operation possibility of DER, hence, the active distribution network is partitioned into zones with DER and zones without DER. Directional node configuring method is proposed to identify the positional relation of circuit breakers (CBs) on boundaries of zones. After configuring each intelligent feeder terminal units (IFTUs) with the directional node relationship information, the connection relationship between zones can be obtained automatically. So that only by communicating with its neighbors, the IFTU can decide which CBs should be opened when a fault occurs. Peer to peer communication technique is established for interacting fault measurement information among the adjacent IFTUs, fast and accurate faulted zone location and isolation can be achieved. Meanwhile, seamless islanding of the zone integrating DERs can be realized to keep supplying power to the islanded feeder continuously after distribution network splitting. Moreover, power balance control for intentional islanding is discussed to ensure the islanding stable. Finally, results of case studies demonstrate the feasibility and effectiveness of the proposed scheme.