Research on Rapid Analysis for Purity of SF_6 via Ion Mobility Spectrometry

摘要

The detection of partial discharge and analysis of sulfur hexafluoride (SF_6) purity in gas-insulated switchgears (GIS) is important for diagnosis and operating state assessment of the electric device. This paper introduced a method for rapid purity detection of SF_6 based on one-way ion mobility spectrometry. The influence of flow rate, temperature and purity of SF_6 on the drift time of SF_6 were investigated in details. The drift time of SF_6 was found to increase with the rising of impurity in SF_6. A time of flight mass spectrometer was used for monitoring of decomposition products in SF_6 from partial discharge. SO_2, SOF_2, SO_2F_2, SOF_4 and SiF_4 were found to the main discharging decomposition products, which lead to the decrease of purity of SF_6.