Improving the quality of liquid insulation of oil-filled electrical equipment by introducing new additives

Stable and reliable operation of oil-filled electrical equipment at power facilities depends largely on the quality of liquid insulation — transformer oil, which is influenced by environmental and operational factors, as a result of which it is flooded, aging with precipitation and oxidation products, which leads to short circuits and breakdowns. About 85% of transformer failures are due to a violation of the insulation system. To increase the service life of transformer oil, it is traditionally added an antioxidant additive ionol, the drawback of which is its high sensitivity to organosulfur compounds. Improving the quality of transformer oil is possible due to a more effective antioxidant additive. Previous studies have shown the ambiguous effect of organosulfur compounds on the performance of transformer oil. In this regard, as well as taking into account an increase in the production and processing of sulfur and sour crude oils, the effect of individual sulfides of various structural group composition on operational indicators, such as stability indicators against oxidation of the oil fraction, saponification number, ether number, absorbed oxygen amount, and corrosion activity, was studied at operating temperatures and in an electric field of 30 kV/cm.

During the study, it was found that cyclohexyldecylsulfide is the most active inhibitory additive to the oil fraction among individual organosulfur compounds. However, diphenylsulfide and diphenyldisulfide reduce stability against oxidation of the fraction, worsening its quality.

It was established that when aromatic cycles in a sulfide molecule are replaced by cyclohexyl cycles, the inhibitory ability increases, increasing the quality of transformer oil and, accordingly, the reliability of operation of electrical equipment as a whole.

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