Study On Fault Location Method In Non-Effectively Grounded Network And Its Application

With the development of human society,the world is advancing every day and the times are changing,but there are also many problems,such as the shortage of power resources and how to supply electricity more efficiently.How to reform the urban and rural power grid project more deeply and design the accurate and reasonable fault location system is the focus of attention at present.After careful design,this topic initially established a set of new power supply network system.This paper is written on the basis of in-depth understanding of the main station of feeder automation system,and then makes a comprehensive study of the small current.It mainly includes the analysis of the small current grounding system and its main characteristics,the steady-state current and transient current flowing through the fault point after the single-phase grounding fault occurs.Taking steady current as the research object,the method of fault point location in small current grounding fault is used,that is,the parameter difference between the two ends of the section is used to determine the fault point.Then,different sections are selected and compared between the normal section and the fault section,focusing on the analysis of the difference between the zero-sequence admittance,the judgment basis of the fault section is established,and the flow chart of the fault analysis is proposed to locate the fault section accurately.It is proved that the transient capacitance current can be used as the criterion of fault line selection and fault location.The reason is that the ARC suppression coil has no effect on this kind of current and the amplitude of the transient current is large.In this paper,the transient zero-sequence current at the secondary protection of a section of operating line(normal line and fault line)is selected to analyze the polarity and amplitude difference of the characteristic component,based on the above research results,a method of line selection——Foshan synthetic method is proposed.Then,the final decision method was used to analyze the two groups of comparative sections.Based on the parameter difference between the two sections,a new algorithm is proposed,that is,the fault section is located by adjacent comparison.Finally,the two methods of fault diagnosis are selected respectively for simulation verification,and the advantages and disadvantages of the above methods are compared to determine the 10kV feeder single-phase grounding fault algorithm,the model of 10kV Feeder single-phase grounding fault line selection and location algorithm research system in Shenyang area is established,and the model of 10kV Feeder single-phase grounding fault line selection and location algorithm research system in Shenyang area is obtained,according to the actual situation,the model has been applied in practice.The research of this paper will promote the reconstruction of intelligent distribution network and the research of 10kV feeder automation system in Liaoning area,at the same time,it has certain practical and theoretical significance for the reconstruction and construction of distribution network in China.