The Distribution Network Single Phase To Ground Fault Location System Design Based On Ad-hoc

Small current neutral grounding system is widely adopted in power distribution networks of 3-66kV in China. When the single-phase earth fault appears in this system, it is difficult to locate the fault accurately because of numerous distribution network branches, complex network structure and minimal grounding current. Therefore, according to the practical problems of project in an area, a single-phase earth fault location system based on Ad-hoc for power distribution network is designed in this paper, in order to locate accurately fault zone.The measuring devices of existing fault location system are installed on the line outlet in the substation. The system is difficult to locate the fault accurately because of obtaining insufficient amount of data. A single-phase earth fault location system based on Ad-hoc is designed in this paper. CPMU installed at each branch acquires large amounts of data; data is transmitted from CPMU to master station based on Ad-hoc communication system, in order to locate accurately fault zone.Based on CPMU distributed measurement technology, this paper proposes the zero sequence current amplitude comparison method and the zero sequence current differential method as practical criterion for fault location system by studying and comparing the features of single-phase grounding fault in isolated neutral system and neutral grounding via arc suppression coil system. In addition, the error of actual data is analyzed and processed, which lies the theoretical foundation on the design of the entire fault location system.Based on the proposed methods of fault location the system includes current phasor measurement units (CPMU), a real-time data transmission and communication system based on Ad-hoc technology and master station application program. This fault location website is realized by ASP.NET platform and the data collected from CPMU. Data is transmitted from CPMU to master station based on Ad-hoc communication system. Data display, fault analysis, fault line positioning and other functions is achieved by WEB. The system designed can quickly and accurately determine the fault line section.In addition, as for the fault location methods proposed in this paper, this paper builds simulation models applying MATLAB based on the line parameters in some areas of practical lOkV distribution network in isolated neutral system and neutral grounding via arc suppression coil system. Through simulation data, testing and verifying the feasibility and accuracy of the fault location system based on Ad-hoc.