基于热失重分析的盆式绝缘子热分解活化能的计算方法

Calculation Method of Thermal Decomposition Activation Energy of Basin-type Insulators Based on TG Analysis

气体绝缘金属封闭开关(GIS)在电力系统中应用广泛,其中盆式绝缘子长期在电热应力作用下不断发生老化降解,严重情况下可能会引发重大事故。盆式绝缘子的老化降解实际上是化学反应过程,因此研究盆式绝缘子的热分解过程具有重要意义。文中基于热分析动力学原理,采用热失重法分析了盆式绝缘子在5种不同升温速率下的热分解过程,采用Flynn-Wall-Ozawa法和Kissinger法计算了盆式绝缘子的活化能。研究结果表明,采用Flynn-Wall-Ozawa第1种方法和Kissinger方法计算结果基本一致,由Flynn-Wall-Ozawa第2种方法计算得到的活化能起初随着转化率的增加而增大,在转化率0.12处达到峰值,然后随着转化率的增大略有下降,并给出了这一现象的微观解释。上述研究对于准确计算盆式绝缘子的活化能,进而为揭示老化机理和评估老化程度具有一定的指导意义。

Gas-insulated metal-enclosed switches（GIS）are widely used in power systems. Among them,basin-typeinsulators have been subjected to aging degradation under the effect of electro thermal stress for a long time,and seri-ous accidents may be caused in severe cases. Aging degradation of basin-type insulator is actually a chemical reac-tion process,so it is of great importance to study the thermal decomposition process of basin-type insulator. Based onthe principle of thermal analysis,the thermal decomposition process of the basin-type insulator under five differentheating rates is analyzed by TG method. The activation energy of the basin-type insulator is calculated by the Flynn-Wall-Ozawa method and the Kissinger method. The results show that the calculated results by the first method of Fly-nn-Wall-Ozawa method and Kissinger method are basically the same. The activation energy calculated by the secondmethod of Flynn-Wall-Ozawa method initially increases with the increase of conversion rate. Peak at a conversionrate of 0.12,then decrease slightly as the conversion rate increases and last gives a microscopic explanation of thisphenomenon. The above research has certain guiding significance for accurately calculating the activation energy ofthe basin-type insulator,revealing the aging mechanism and evaluating the aging degree.