基于特征气体SO_(2)F_(2)的SF_(6)气体绝缘设备的过热性故障诊断

Overheating Fault Diagnosis of SF_(6)Insulation Equipment Based on Characteristic Gas SO_(2)F_(2)

利用SF_(6)分解产物检测来判断GIS故障发展程度已成为一种有效手段,在搭建的实验平台上展开200℃~360℃局部过热模拟实验,研究SF_(6)热分解特性。当实验温度较高时(320℃~360℃),新增SO_(2)F_(2)、H_(2)S、COS三种产物。在绝缘设备充满大量SF_(6)子的背景下,分解产生的H_(2)和COS的含量极少,给气体检测带来了困难。文中提出将SO_(2)F_(2)作为设备故障进入严重状态的标志气体,同时用量子化学计算法在B3LYP/6-311G(+d,p)水平下对SO_(2)F_(2)生成机理和能量条件进行研究。发现SO_(2)F_(2)通过F_(2)碎片与气室内SO_(2)反应、F原子与SO_(2)F结合、SOF 4水解反应这三条途径得到,其中SO_(2)与F_(2)反应是SO_(2)F_(2)的主要来源。实验现象与理论计算均表明:SO_(2)F_(2)的形成机制与高温息息相关,SO_(2)F_(2)出现,标志着设备故障处温度较高,SF_(6)绝缘能力已遭到严重破坏。

It has become an effective method to judge the fault development of GIS by using the detection of SF_(6)decomposition products.Overheating simulation experiments were carried out on the established experimental platform to study the thermal decomposition characteristics of SF6.When the experimental temperature was high(320℃~360℃),SO_(2)F_(2)、H_(2)S and COS were detected.Under the background that the gas insulation equipment is filled with a large amount of SF_(6),the amounts of H_(2)S and COS is very small,which poses a great challenge to gas detection.Based on this,the generationof SO_(2)F_(2)can effectively reflect the SF_(6)insulated equipment is under deteriorating.Meanwhile,the generation mechanism and energy conditions of SO_(2)F_(2)are studied at B3LYP/6-311g(+d,p)level by using quantum chemical calculation method.It was found that SO_(2)F_(2)was produced mainly through the following three reaction pathways:F_(2)+SO_(2)→SO_(2)F_(2),F+SO_(2)F→SO_(2)F_(2),SOF 4+H_(2)O→SO_(2)F_(2)+2HF.Experimental phenomena and theoretical calculations have shown that the formation mechanism of SO_(2)F_(2)is closely related to fault temperature.The presence of SO_(2)F_(2)indicates that the fault temperature of the equipment is high and SF_(6)insulation capability has been seriously damaged.