Investigation of activation energy for aged epoxy resin insulators in GIS

Gas insulated switchgear (GIS) is widely used in power systems, in which the basin insulator as the main solid insulation component fails under the action of long time electrothermal stress. The aging degradation of basin insulators is a slow chemical reaction process. Therefore, the activation energy method can be used to effectively evaluate the aging state. In this paper, the activation energy calculated by the thermal analysis and temperature-frequency dielectric spectroscopy methods are analyzed. The activation energy of epoxy resin used for basin insulators after electrothermal aging is analyzed using temperature-frequency dielectric spectroscopy. The results show that the activation energy obtained by thermal analysis is larger. The activation energy of materials after electrothermal aging increases with the aging time. The electric field accelerates the aging process of materials. The above studies show that the thermo-frequency dielectric spectroscopy method is simple to operate without material damage. It can also effectively estimate the degree of material aging, which is more suitable for online detection of basin insulators.