Research On SF₆ Discharge Decomposed Component Apparatus And Experimental Method

Partial Discharge (PD) is the normal form in the beginning of insulation fault in Gas Insulated Substation (GIS). PD can induce SF6 to decompose. Different types of defects may lead to different decomposition process, decomposition rate and gaseous decomposed components. It is significant to diagnosis and forecast of faults in GIS and safety of GIS operation that we conduct in-depth research on the process and elements of SF6 decomposition and relative concentration relation of kinds of SF6 decomposed components to find out characteristic gas which could indicates specific type of defect and develop diagnosis method based on the measurement of decomposed component. According to practical defect modles, this thesis conducts research on analysis of SF6 decomposed components based on techniques of electrical measurement and gas chromatography. The main achievements are as follows,â‘ A multi-functional experiment apparatus is devised. This apparatus are in good condition in the aspects of sealing, pressure resistibility and prevention of corona. It admits installation of three types of defect modles, adjustment of voltage, electrode distance and SF6 pressure. It provides an effective platform for PD experiment in SF6;â‘¡Pulse current detecing system, gaseous component analysis system and ultraviolet detecing system are devised. Practical detecting indicates that pulse current detecing system could detect the waveform, phase and amplitude of pulse current; gaseous component analysis system could detect 1 ppmv of SO2F2, SOF2, SO2, CF4; ultraviolet detecing system could detect ultraviolet photons from PD. Three kinds of detecing system provide techniques to research on the process, elements and affecting factors of SF6 decomposition;â‘¢Basic experimental method is devised and the condition of gas chromatography is optimized to garanttee the availability, effectiveness and precision of experimental data;â‘£Under different experimental condition, we conduct experiments to gain data of SF6 decomposed components, microgram of ultraviolet photons and pulse current. Based on the experimental data, we make comparison.