Study On Detection Conditions Of The Main Products Of SF₆Decomposition By Gas Chromatography

With the great development of Chinese economy, the power industry has alsodeveloped rapidly. Many countries are focusing on how to detect the products of SF₆decomposition and the problems of high voltage equipments, such as GIS, to ensure thereliability and security of the power grid. It is of important practical significance on thedevelopment of the power system to detect the main products of SF₆decomposition, inorder to make sure GIS（Gas Insulated Switchgear） and other high voltage equipmentscould work normally and predict the potential problems.In this article, a semiconductor high and low temperature cold trap equipment waschosen to adjust the characteristic decomposition products to the detection limitconcentration by excluding the impact of SF₆and cryogenic enriching part of thecharacteristic decomposition products, which provide with a basis for further research onthe main products of SF₆decomposition.The best experiment conditions about gas chromatography and semiconductor highand low temperature cold trap equipment were determined through a number ofexperiments: HP6890GC-μECD（Hewlett-Packard, USA）; HP-PLOT/Q capillarycolumn（30m×0.32mm×20μm）; injector temperature120℃; splitless injection（split ratio5.0）; sample amount250μL; carrier gas N2（99.9995％）; carrier gas flow-rate1.5mL/min;makeup gas N2, makeup gas flow-rate30mL/min; oven temperature from40℃to120℃at heating rate10℃/min, continuing2min at120℃; chromatography workstation HP3398A; cold trap equipment’s cooling temperature-60±1℃; desorption temperature50±1℃; carrier gas N2（99.9995％）, carrier gas pressure0.2MPa, carrier gas flow-rate20mL/min; ten-way value switching time65min.However, as the experiments showed that SOF₂was not detected under suchconditions, and the concentration of SO₂F₂after cryogenic enriching was only one tenthof that before. However, SOF₂was not be detected under such conditions, and the concentration of SO₂F₂after cryogenic enriching was only one tenth of that before.