In order to study the effect of amine compounds on insulating oil

based on existing researches

by selecting cyanamide

melamine and polyacrylamide as composite heat stabilizers

we prepared insulating papers containing different ratios of dicyandiamide

melamine and polyacrylamide and without reagent. After drying and oil immersing process

the thermal aging test was carried on at 130 ℃ for 30 days to measure the thermal aging characteristics of the insulating oil such as acid value

moisture

dielectric loss

and breakdown voltage. The results show that the amine compound modified insulating paper will reduce the moisture in the insulating oil

which has a negligible influence on the breakdown voltage of the insulating oil

but will accelerate deterioration of the insulating oil that lead to the increase of acid value and dielectric loss. Besides

the paper containing 2.25% Melamine

0.75% dicyandiamide and polyacrylamide

and 0.2% polyacrylamide has the greatest thermal stability and a negligible effect on insulating oil. Then through the analysis of copper content and frontier orbital energy gap

it is believed that ammonia produced by amine compounds promotes the formation of copper ions to accelerate the aging of insulating oil.