Design And Realization Of High Voltage Cable Fault Location System

In recent years, with the sustained and rapid development of the power grid construction, the underground power cable transmission and distribution lines gradually replacing overhead lines provides a prerequisite for the crisp and clean city, which is an important sign to measure the degree of the techno economic level of city power grid. However, in the process of manufacture, construction, operation and maintenance for the electric power cable, some inevitable problems such as the quality of the products, overload operation and external damage are the direct causes of high voltage cable fault. The traditional method of traveling wave fault location will not be able to meet the stability and economy of the system fault location requirements. Therefore, the new method on fast, accurate fault location of high voltage transmission line has become a hot research topic of domestic and international science and technology workers. This paper designed a more reasonable high voltage cable fault location system, completed the preliminary design of the software, and verifies its reliability and practicability.At present the research on high voltage cable fault location mainly focuses on two terminal locations based on GPS. Because the high cost, synchronous double end time value determined by the satellite, and the error must be reduced to less than 10 ns, it is less applied in civil field. The non-GPS double end positioning method based on the high speed optical transmission and high precision integrated circuit described in this paper has the properties of convenient installation, simple operation and the acquisition accuracy control in no more than 10 ns.The key technologies of the two terminal fault location system in this paper include optical fiber part time precision control, the design of high-frequency transformer, double end, online monitoring system access and so on. Propagation time of the traveling wave between the fault point and the two ends of cable is used to find the cable fault location. The system using on-line monitoring can real time obtain the fault location, which lay the foundation of the construction of high voltage cable network operation condition monitoring and condition based maintenance expert system to carry out the analysis of multi parameter monitoring and high voltage cable network operation state and further carry out condition based maintenance. The ultimate purpose is the realization of fault warning, smart transmission grid analysis, emergency command, and the quick response. The two terminal fault location system proposed in this paper also makes use of the advanced automated design software "Kingview" to realize the comprehensive automation of substation equipment management, and realize the historical data query, online real-time monitoring, report drawing display and database management and other advanced functions...