Research On Application Of GIS Partial Discharge Detection Technology

GIS has become the mainstream of electrical equipment in substation because of its small occupation area,compact structure,high reliability characteristics,low noise and less daily maintenance work and so on.However,GIS equipment insulation failure will cause a large blackout area.And because of its complex structure and high sealing,GIS needs more repair time to recover.It is partial discharge which leads to GIS insulation failure.Therefore,we are going to do a deep research on GIS partial discharge live detection technology and timely detect of potential insulation defects and faults inter GIS equipment.It will have an important significant for the improvement of GIS health level and protection of GIS safe and reliable operation.Firstly,this paper explain the mechanism and characteristic of partial discharge of GIS devices.Based on this,several common GIS partial discharge live detection technologies are analysed,such as ultra high frequency(UHF)method,acoustic emission(AE)method.Based on the characteristics of the two methods,the use of UHF signal fast locating partial discharge sources as well as with AE signal with the realization of The UHF and AE combined precise localization of partial discharge source approach are proposed.Secondly,a partial discharge detection system is designed,and have a detailed introduction for the hardware and software of this system: it includes UHF and AE sensor,signal amplification circuit,A/D convert,data storage,data transmission and so on.then,a laboratory platform for simulating typical partial discharge defects of GIS has been set up,these four types of partial discharge are: free mental particles,corona,suspension discharge,air-gap discharge.A large number of UHF and AE partial discharge signal detection map and data of typical defects are obtained through the experiment,and the mapping characteristics of the typical defects are summarized.Finally,the GIS partial discharge detecting system which is mentioned in this paper is used to detect GIS equipment in several substations in service.By using the UHF and AE combined localization approach to precisely local the partial discharge source.And then the kind of partial discharge is confirmed by comparing the detection map with typical map.Base on the results,the overhaul program can be made to ensure that the hidden danger of devices will be eliminated timely.