Applied Research On Detection For Partial Discharge In GIS

Fully enclosed gas insulated substations(GIS)is a combination of high voltage electrical equipment in the 1970 s,which is widely used in electric power system.It has the advantages of small,good sealing and high reliability etc.GIS insulation performance testing can ensure the stable operation of power system.Partial discharge phenomenon can reflect the GIS equipment's insulation status inside,so in order to better understand operation condition of the GIS equipment and the insulation of the internal defects,we can judge by detecting partial discharge phenomenon.Test results should be deliverd to users in time,then provide accurate and reliable basis of GIS's maintenance.This article analyzes the model of partial discharge in GIS,and according to the discharge characteristics,we develop a set of complete GIS uhf partial discharge on-line detection and positioning system.The hardware part of this system,that is partial discharge data acquisition system,according to the requirements,we design partial discharge data analysis system,which include high sensitive uhf sensor,signal conditioning and amplification filter module.Using C++ software as a development platform,the software system deals the collected signals from the hardware system by the high-speed data acquisition module and the I/O data processing module.It calculates the peak discharge and discharge times of each measuring cycle,etc.Real-time waveform,map PRPD spectrum waveform analysis of partial discharge and discharge type can be displayed on the upper machine.PC system has alarm function at the same time.When they teste the GIS insulation discharge phenomenon occurs,timely it can feedback to the users,ensuring reliable operation of the power system.Finally,the application in ruibao substation and guishan substation of 500 kv,shows that the system can accurately and efficiently detect the discharge point location.