中文摘要：

由于微H2O对SF6在过热性故障下的分解特性有较大影响,要利用SF6分解特征组分分析法来诊断SF6设备过热性故障的严重程度和发展趋势,必须对诊断结果有较大影响的微H2O因素进行深入研究,掌握其影响规律,进而对诊断结果进行校正。为此,在研制的SF6电气设备过热性故障模拟试验平台上,模拟产生局部炽热高温使SF6发生分解,用气相色谱仪和气相色谱–质谱联用仪对不同微H2O含量下的SF6过热分解组分进行定量测定,以获取微H2O含量对特征组分及特征比值的影响特性与规律,确定相关的校正方法。研究表明,微H2O对SF6过热分解各产物有效产气速率影响显著,且影响规律各不相同;但各特征组分有效产气速率和特征比值c（SOF4？SO2F2）/c（SOF2？SO2）均与微H2O含量有较强的关联性,经过相关校正可作为有效诊断SF6电气设备过热性故障的特征量。

英文摘要：

decomposition Since trace H2O can directly affect SF6 characteristic under overheating fault, it is important to study trace H2O which has the significant effect on diagnosis results in-depth and master its influence regularity, so as to correct the diagnosis results accurately and establish perfect SF6 overheating decomposition database when the gas analysis method is used to determine the severity and development trend of overheating fault in SF6 electrical equipment. In this paper, the local high temperature was simulated to make SF6 decompose on the designed SF6 thermal decomposition experimental system. Gas chromatograph and chromatography-mass spectrometry were used to measure the SF6 overheating decomposed components under different H2O concentrations quantitatively, so as to obtain the influence characteristics and regularities of trace H2O on characteristic components and characteristic ratios and determine the correction methods eventually. Results show that H2O has significant effect on the effective gas rate of SF6 thermal decomposition components, and the influence regularities are not identical. However, both the effective gas rate of each characteristic component and the characteristic ratio c（SOF4＋SO2F2）/c（SOF2＋S02） have a good relationship with H2O concentration, thus they can be used as the characteristics of overheating fault diagnosis through the relevant correction.