The effect of corrosive and antioxidant of dibenzyl disulfide (DBDS) on the oil-paper insulation

Abstract

As, a kind of sulfur antioxidant, dibenzyl disulfide (DBDS) generally exist in the mineral insulating oil, which can improve the oxidation stability of oil. However, DBDS can also lead to corrosion problems of transformer oil. To investigate the effect of the corrosive action and the antioxidant action of DBDS on the oil-paper insulation, oil samples with different DBDS concentration (0–200mg/kg) were made and conducted to perform thermal aging experiments together with insulation windings at 130Ό under the condition of nitrogen. After the aging experiment, the copper strip and insulating paper surface were observed, the properties of insulating oil were also measured and analyzed. Experimental results showed that when the insulating oil contained less than 25mg/kg DBDS, the antioxidant effect of DBDS would be dominant, the oxidation stability of insulating oil was improved, the performance of oil was better than that of excluding DBDS samples. When the insulating oil contained more than 25mg/kg DBDS, the corrosive effect of DBDS will be greater than its antioxidant effect, copper ions and acid will be accelerated, it will lead to more serious of aging oil.