Studies on the anti-oxidative ability of quinones in natural ester based insulating liquids for transformers

Abstract

Abstract Due to the unsaturated olefinic structure of natural esters, their antioxidation ability is generally poorer than that of the mineral oils, thus certain antioxidants were commonly added as the additives to improve the oxidative stability of natural ester for their service as transformer oils. The present study reported the influences of adding quinones as additives on the oxidative stability of versatile natural esters. It was found that, under the accelerated oxidation conditions, added quinones could improve the oxidative stability of these tested natural esters through decreasing their acidic values, viscosity increase and dielectric losses to certain extent, thus providing a new category of antioxidants to improve the oxidative stability of natural ester based transformer oils.