Partial Discharge Research On UHF Detection For GIS

State grid released a concept of strongly smart power grids, which takes the UHV power grid as the backbone for grid and base on the coordinated development of all levels grids. The smart power grids is characterized by informationtechnology, automation and interactive. Strategic objectives for building a unified strongly smart grid is achieved by 2020. Among them, the intelligent switching device is an important part of the smart grid, which is also an important part to ensure the implementation of the strategy of "smart grid". As an important part of online monitoring for intelligent GIS,the study of partial discharge (PD) for GIS is a focus of academies, power sector, high-voltage electrical equipment manufacturing enterprises.SF6 Gas Insulated Substations(GIS) is applied abroadly now for all levels from 66KV to 550KV, because of its small footprint, high reliability, small maintenance workload and long maintenance cycle.But because of its sealing structure, it is difficult to localization and repaire when the flashover come to being inside. There are a lot of insulation failure during internal faults and the partial discharge (PD) for GIS is threatened and forms of thems. So it is important to monitor the partial discharge.Methods of GIS PD monitoring is classified in this paper, analysised of their advantages and disadvantages. the principles of UHF and the characteristics of electromagnetic waves are described.Designed A GIS Partial Discharge Monitoring System based on the UHF signal pattern recognition technology. It is in the GIS open media window on the chamber and installed a UHF antenna detection, using Peak detector technology, acquisition and processing data through the computer.Produced two kind of Discharge model:Metal particle discharge model and Metal cusp discharge model. Using GIS partial discharge monitoring system, Tektronix TDS2022B Oscilloscope and Shanghai Jia special instrument PD by Several experiments, get a large number of real and reliable test data. Summary the signal characteristic rule, The waveform parameters can be pattern recognition method to provide a reference, at the same time, to provide fault diagnosis fault type identification basis for the GIS partial discharge monitoring system. Discuss the UHF methods for location of PD.