Research On Fault Location Of High Fault Tolerance In Distribution Network Based On Multi-Source Information

Distribution network as a direct link with the power users,the reliability of its operation will have a direct impact on the user's power satisfaction.After the distribution network breaks down,locating the fault point quickly and accurately has great significance to reduce the downtime and improve the reliability index of the distribution network.At the same time,it will also provide the basis for the subsequent fault isolation and fault recovery process.In this paper,the following studies were carried out.Firstly,aiming at the disadvantages of fault location using a single information source,a fault location algorithm of distribution networks based on D-S evidence theory and multi-source information fusion is proposed.First of all,using the system information of power distribution automation and the information of customer electric information acquisition system,the candidate fault section set and its basic probability distribution function are obtained based on the BPSO optimization algorithm and form the evidence body.Then,D-S evidence theory is used to fuse the information to get the final fault section.The case study verifies the validity and fault tolerance of the proposed method.In the extreme case where the fault information is wrong or the upload information is wrong,the algorithm can still accurately determine the fault section.Secondly,aiming at the complex distribution network with low degree of automation and many branch lines,based on the realization of the fault section positioning,it is proposed to use the feeder terminal unit and the power quality monitoring system to record the voltage sag information and current information for the accurate positioning of the fault point.The method is not affected by the pseudo fault point,at the same time,it only needs a simple complex operation,does not need online simulation operation to form a large voltage sag database to match,or to calculate the power flow for the distribution network.For complex distribution network with more nodes,the operation efficiency is high.Through the simulation calculation of the actual distribution system of 134 nodes,the method is proved to be effective and efficient in the fault location of complex distribution networks.Finally,on the basis of the above research and Zhejiang University South China Institute of Technology Smart Grid Center Distribution Network Dynamic Simulation Laboratory as a research platform,the practical application of fault diagnosis system in distribution network is studied.The system power distribution system topology analysis,distribution network fault location algorithm,SVG operation and other research results were implemented in the system module practice.From the system data architecture,the development of software configuration,functional architecture and functional interface and application effects of the system development and implementation are introduced.The research results will provide theoretical guidance and key technical support for the realization of distribution network fault location,which is of great significance to the fault location of distribution network in engineering practice.