Study on the Aging, Discoloration, and Thermal Behavior of Epoxy Resin Insulators in High-Voltage Switchgear

Long-term operation of insulating components within high-voltage switchgear can lead to insulating aging under the coupled effects of electrical and thermal stresses. The contacts and busbars within the switchgear may experience abnormal heating due to aging or excessive contact resistance, which is one of the significant causes of switchgear failure. This paper investigates the aging discoloration and thermal aging of insulating components, primarily focusing on epoxy resin insulators. Initially, based on the correlation between the degree of thermo-aging of epoxy resin insulators and their color change, thermal aging experiments are conducted to obtain insulators with varying degrees of aging. The degree of aging is categorized according to the noticeable changes in color. Subsequently, the remaining service life of the insulators at different aging stages is calculated through mass loss experiments and equivalent aging standards. Additionally, the temperature variations of epoxy resin insulators at different aging stages are explored through experimental investigation. The experimental results indicate that under the same experimental temperature, the longer the aging time, the darker the color of the epoxy resin samples. Under identical conditions, there is no significant change in temperature for epoxy resin insulators of different aging degrees.