Research On Detection And Location Of Partial Discharge For GIS Based On Acoustic And Electrical Joint

With the development of the State Grid,for the needs of transmission and distribution of higher voltage levels,GIS(the Gas Insulated metal-enclosed Switchgear)has a series of advantages such as its compact structure,safe and reliable operation,and easy maintenance,and so on,a large number of power systems are put into operation.However,it will inevitably cause some insulation defects in the manufacturing,transportation and installation process,and due to the closure,the discharge phenomenon is not directly visible.In the event of an insulation failure,it will cause a major accident,which will lead to the safe operation of the power system.National life has a huge impact,so it is especially important to detect and locate faults.The most effective method for GIS insulation detection is PD(Partial Discharge)detection,which is a precursor to causing insulation degradation and causing failure.PD testing can demonstrate the insulation status of the equipment,timely and effectively find early insulation faults and abnormal signals of GIS equipment,and determine the type of fault,and make predictions for its subsequent development,locate insulation defects as soon as possible and make corresponding treatment,prevention The accident occurred.Therefore,partial discharge detection is the focus of this study.This paper first introduces the basic concepts and types of partial discharge,and the significance of PD detection.Partial discharge is a kind of pulse discharge,and a series of physical phenomena and chemical phenomena such as optical,acoustic,electrical and mechanical vibrations are generated inside and around the GIS equipment.These phenomena,which accompany partial discharges,provide a test basis for detecting the internal insulation of the device.Subsequently,several major GIS partial discharge detection methods were analyzed,such as UHF(Ultra High Frequency)and AE(Acoustic Emission),and their equipment composition,detection principle,usage method,and map were introduced in detail.Analysis,precautions,etc.According to the advantages and disadvantages of the two methods,a sound and electricity combination detection method is proposed.The method has strong anti-interference ability and high detection sensitivity.Then introduced several main GIS partial discharge discharge power source positioning methods,and proposed a joint positioning method for ultra-high frequency and ultrasonic waves that can be accurately positioned.Secondly,the actual case of partial discharge detection and location using the acoustic-electrical combination method in the field is analyzed.The field measurement shows that this method can effectively eliminateinsulation hazards,accurately identify the types of GIS internal insulation faults,and can accurately position and discharge the power supply.Location,given exact inspection opinions,provides a powerful guarantee for the safe and stable operation of the power system.