针-板缺陷模型下局部放电量与SF6分解组分的关联特性

为了定量判断气体绝缘组合开关电器(GIS)内金属突出物缺陷所产生局部放电(PD)的严重程度,在自建的SF6放电分解实验平台上,用针-板缺陷模型产生PD使SF6发生放电分解形成特征组分,分别在不同电压等级下进行96h实验,采用气相色谱法对分解组分进行定量测定,同时用50Ω无感电阻检测PD量大小,深入研究了PD量与SF6气体分解组分之间的关联特性,结果表明,针-板缺陷PD下SF6分解可产生CF4、CO2、SO2F2、SOF2等组分,SO2F2和SOF2的体积分数及产气速率与每秒平均放电量Qsec关联性良好,SO2F2和SOF2的体积分数及产气均方速率随Qsec增大而增加,而(SOF2+SO2F2)与(CO2+CF4)的体积分数比值随Qsec近似呈线性增长,CF4与CO2以及SOF2与SO2F2的体积分数比值可作为较大Qsec的辅助判据,因此,可以通过SF6气体组分定量分析来判断GIS设备内部PD的程度。

Correlation Character Between Partial Discharge Quantity and SF6 Decomposition Components Under Needle-plate Defect Model

In order to quantitatively estimate PD severity caused by metal protrusion defect in GIS,SF6 was decomposed by PD in needle-plate defect model to form characteristics components,and the experiment had been carried out for 96 h under different voltage levels.The decomposed components were detected by gas chromatography,and charge quantity was detected by 50 Ω resistance.The results show that the components such as CF4,CO2,SO2F2,and SOF2 are produced,the volume and production speed of SO2F2 and SOF2 correlate well with mean charge quantity per second(Qsec);within the same interval,the volume and production speed of SO2F2 and SOF2 increase with charge quantity.The ratio of(SOF2+ SO2F2)/(CO2+CF4) increases proximately linearly with charge quantity,while CF4/CO2 and SOF2/ SO2F2 can be used to be the auxiliary parameters to determine larger Qsec.Therefore it is suitable that SF6 decomposition components can be used to quantitatively determine the PD severity in GIS.