广东省220kV及以上GISSF_6分解产物分析

Analysis of SF_6 Byproducts of Gas Insulated Switchgear (220 kV and Above) in Guangdong Province

六氟化硫(SF6)气体在电弧、电火花和电晕放电的作用下会发生分解,产生二氧化硫(SO2)、四氟化碳(CF4)等分解产物。检测SF6分解产物(色谱法、电化学法)是诊断SF6气体绝缘设备内部运行情况的一个强有力手段。为此,总结了广东省74个220kV和500kV全封闭组合电器(GIS)变电站共3770个气室中SF6分解产物的体积分数,为SF6GIS潜伏性故障及其故障类型判断累积经验。结果显示:SF6GIS中二氧化碳(CO2)、CF4、氟化亚硫酰(SOF2)、氟化硫酰(SO2F2)、十氟化二硫酰(S2OF10)、SO2和硫化氢(H2S)都呈偏正态分布,CO2、CF4、SOF2、SO2F2、S2OF10的体积分数均低于1000×10-6,SO2的体积分数均<3×10-6,H2S的体积分数均<1×10-6。500kVGIS设备中SF6分解产物体积分数低于220kVGIS设备;运行时间越长,设备中SF6分解产物的体积分数越高。

In the occurrence of arcs discharges, spark discharges and corona discharges, sulfur hexafluoride （SF6 ）would be decomposed to complicated byproducts such as sulfur dioxide （SO2）, carbon tetrafluoride （CF4）, etc. Analyzing the concentrations of these byproducts, which can be determinated when the electric equipment is electriferous, is an effective method to judge the internal condition of GIS. The fault of GIS and the position of the fault can be known by SF6 byproducts analysis. There are many cases about bow to judge the electric equipment faults by analyzing SF6 byproducts, but with little experience about how to judge the latent faults. The article concluded the concentrations of SF6 byproducts in 74 220 kV and 550 kV GIS transformer substation （3770 gas chambers in total） in Guangdong Province. The concentrations of carbon dioxide （CO2 ）, CF4 , thionyl sulfide （ SOF2 ）, sulfuryl fluoride （SO2F2 ）, disulfuryl decafluoride （S2OF10 ）, SO2 and sulfureted hydrogen （ H2S） were in partial normal distribution. The concentrations of CO2, CF4 , SOF2, SO2F2 , S2OF10 were all below 1000×10^-6 ; the concentrations of SO2 were below 3×10^-6 ; the concentrations of H2 S were below 1 ×10^-6. The SF6 byproducts concentrations in 500 kV GIS were lower than those in 220 kV GIS. The SF6 byproducts concentrations were higher in GIS that have been operating longer.