The Algorithm Research Of Fault Diagnosis And Recovery Reconstruction On Power Distribution Network With Distributed Generation

As the earth non-renewable energy reducing every day, people pay attention to resources and the environment more and more. The distributed generation (DG) as a kind of renewable energy source that is available for supplying power for the distribution network has attracted worldwide attention of the power system. The distributed generation which as a development trend of energy supplying usually is access in feeder terminal of the distribution network, and it has the advantages of environmental protection. But also its access will bring some bad influence to network. Like the power flow will lead to relay protection system refusing to move or misoperation, and then make the existing protection system and restore reconstruction system show deficiencies.The study of distribution network with DG in this article is based on the distribution network automation system. So the concept and operation mode of the distribution network automation is made on the basic introduction. Then article introduces the basic concept, common types and modes of operation of distributed generation, and analyzed the influence of fault location and recovery reconstruction when DGs accessed to distribution network.According to the characteristics of the power grid with DG, this paper chooses genetic algorithm as a fault location method. Because of the accessing of DG, the structure of distribution network is changed from single power supply into the multi-source network. Firstly the concepts of the main power supply, the secondary power supply, upstream and downstream circuit are proposed. And then improved the genetic code and optimized the algorithm of the switching function and fitness function to prevent the leakage and miscarriage of justice on fault location.In the reconstruction of recovery, establish a mathematical model of distribution network with DG recovery. In order to increasing the degree of DG playing role in distribution network when modeling, make DG also running and allow DG island operation when fault occurs. Distribution network fault recovery model is multi-objective and multi-constraint, therefore, using the multi-objective optimization characteristic of genetic algorithm solve this model, and concluded that recovery reconstruction scheme. Finally, verify the feasibility of reconstruction model of distribution network and the validity of the algorithm through the simulation of example IEEE33.