Research The Impacts Of DG On Automatic Reclosing In Distribution Networks

With the increasing energy needs of modern society, primarily fossil energy based on coal and oil is less and less, and it will bring series of impacts on the environment. Distribution Generation (DG), such as solar generation, wind generation, geothermal generation, has the characteristics of flexible and convenient and compatible with the environment, which becomes the focus of global concern. In the future, there will be more and more distributed generation incorporated into distribution network, while the traditional distribution network protection and recloses is set based on the single-direction power flow from the top to the bottom. The access of distributed generation makes the power network become into a double power supply system or multi-power supply system, which will bring series of challenges on the original protection and recloses, such as non-synchronous reclose. So it is very necessary to study DG influence on the automatic reclosing.In this paper, the PV&BATTERY generation system is built using PSCAD/EMTDC software and their different operating mode are studied. Based on the model and simulations, the influence of DG on accelerating protection before reclose is given in details. Some protection improvements for these effects are given out. When the DG is out of the system, the influence of DG on reclose inspection without voltage. In order to avoid the non-synchronous reclose, it is programmed to implement the synchronous reclose between the DG side and the system side by MATLAB&PSCAD interface.Finally, the impacts of DG on local control mode and the remote control mode feeder automation are given in the paper. The impact of DG on local control mode mainly has coordination between the re-closer and the fuse; co-ordination between the re-closer and sectionalize switch; the coordination between the re-closer and the re-closer. The impact of DG on the remote control mode based on FTU is analyzed. Some improvements are given out to reduce the impact of DG on feeder automation.