中文摘要：

为了获取不同气压下SF6的局部放电（PD）分解特性及其变化规律,在搭建的试验研究平台上,开展了不同气压下SF6的PD分解特性实验。实验中,采用气相色谱仪和气质联用仪对分解生成的特征组分进行了定量测定。根据实验结果,分析了特征组分的变化规律及气压变化造成的影响。实验结果表明：随着气压的增加,特征组分CO2、SO2、SOF2的生成速率会明显减小,且SOF2的变化最为显著,但特征组分SO2F2的生成速率仅略微降低,进而对诊断故障的特征比值φ（SOF2＋SO2）/φ（SO2F2）有较大的影响。为此,提出一种影响不明显的特征比值φ（SO2F2＋SOF2＋SO2）/φ（CO2）作为故障诊断的新特征量。

英文摘要：

In order to obtain the decomposition characteristics of SF6 under partial discharge （PD） at different gas pressures and their changing pattern, we established an experiment platform and carried out PD decomposition experiments of SF6 at different gas pressures. In the experiments, gas chromatography and gas chromatography-mass spectrometry were adopted to quantitatively determine the characteristic components of decomposition. Then we analyzed the variation of these characteristic components at different gas pressure and the role of gas pressure in this process on the basis of experiment results. It is concluded that, with increasing pressure, the generation rate of some characteristic components＇ （such as CO2, SO2, SOF2） significantly declines, while SOF2 has the most significant change, but the generation rate of another characteristic component, SO2F2, only reduces slightly. This troubles the diagnoses based on the signal characteristic ratio φ（SOF2＋SO2）/φ（SO2F2）. Therefore, we proposed to use a characteristic ratio, φ（SO2F2＋SOF2＋SO2）/φ（CO2）, which is not obviously affected by pressure, as a new feature quantity for troubleshooting of SF6 devices.