Islanded operation of UK radial distribution: Earthing strategy

Earthing has been identified as one of the main issues pertaining to an intentional islanding. The issue is significance for any rotating type of DG operating in Networks a distribution networks. The problem arises for a system adopting single point earthing when a DG is disconnected from the grid and continues to supply power to an islanded system that does not contain an earth connection. Therefore, this paper describes a study that considers the earthing arrangement for a single point, low impedance earthed distribution network with a particular emphasis on the earthing requirements when a section of the network is operating islanded. The study is evaluated on a simulated network constructed using the PSCAD/EMTDC simulator. The study showed that an appropriate operating procedure for islanded operation is required to ensure continuity of the earth connection in the islanded system.