Abstract The main aim of this study is the thermal characterization of an organic insulation. This insulation is a compound of two mono-component epoxy resins: Epoxylite® primer and Elmotherm® varnish. A mono-component epoxy resin usually needs a high temperature to cure; through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), non-isothermal curves are obtained, allowing the estimation of activation energies of curing and decomposition processes respectively. If Model Free Kinetic (MFK) is used from DSC curves, it is possible to simulate isothermal curves at different temperatures and times, plotting activation energy as a function of the conversion degree. The simulation from TGA curves can be used to estimate lifetime of the resins and compare them following the Toop method. DSC also allows measurement of thermal conductivity, the melting peak of metallic gallium being used for this measurement. Finally, water diffusion in resins is studied. Currently, the Materials Performance research group of UC3M is working on the European project named “Essial”, where this organic insulation is used to protect the windings and the whole transformer from the environment. The results obtained will be used to determinate the optimal operating range for this insulator, demonstrating that both epoxies are required to achieve the insulating performance of the transformer and long curing times are required for full curing of Epoxylite®.

中文翻译：

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变压器绝缘用两种单组分环氧树脂的热特性和扩散率

摘要 本研究的主要目的是有机绝缘材料的热特性。这种绝缘材料是两种单组分环氧树脂的混合物：Epoxylite® 底漆和 Elmotherm® 清漆。单组分环氧树脂通常需要高温才能固化；通过差示扫描量热法 (DSC) 和热重分析 (TGA)，获得了非等温曲线，可以分别估算固化和分解过程的活化能。如果从 DSC 曲线中使用无模型动力学 (MFK)，则可以模拟不同温度和时间下的等温曲线，将活化能绘制为转化度的函数。TGA 曲线的模拟可用于估计树脂的寿命并按照 Toop 方法进行比较。DSC 还允许测量热导率，该测量使用金属镓的熔化峰。最后，研究了水在树脂中的扩散。目前，UC3M 的材料性能研究小组正在开展名为“Essial”的欧洲项目，该项目使用这种有机绝缘材料来保护绕组和整个变压器免受环境影响。获得的结果将用于确定该绝缘子的最佳工作范围，证明需要两种环氧树脂才能实现变压器的绝缘性能，并且需要较长的固化时间才能使 Epoxylite® 完全固化。UC3M 的材料性能研究小组正在开展名为“Essial”的欧洲项目，在该项目中，这种有机绝缘材料用于保护绕组和整个变压器免受环境影响。获得的结果将用于确定该绝缘子的最佳工作范围，证明需要两种环氧树脂才能实现变压器的绝缘性能，并且需要较长的固化时间才能使 Epoxylite® 完全固化。UC3M 的材料性能研究小组正在开展名为“Essial”的欧洲项目，在该项目中，这种有机绝缘材料用于保护绕组和整个变压器免受环境影响。获得的结果将用于确定该绝缘子的最佳工作范围，证明需要两种环氧树脂才能实现变压器的绝缘性能，并且需要较长的固化时间才能使 Epoxylite® 完全固化。