Moisture content as an important integral parameter of transformer oil quality in power transformers of 10/0.4 kV substations

¹ Saratov State Agricultural University n. a. N.I. Vavilov, Russia
² Central Production Department of Saratov Distribution Grids, a branch of IDGC of Volga, PJSC)

^* Corresponding author: v.a.trushkin@mail.ru

Abstract

The main element characterizing the transformer efficiency is the state of its isolation, and the first thing is operating oil, which can perform its functions for a long time with timely restoration of its properties. Transformer oil is the main dielectric being in contact with the external environment, interacting with solid insulation and carrying a large amount of diagnostic information. Analysis of the development of transformer insulation damage showed that the main catalyst for accelerating the aging process of the oil is the appearance of moisture in it. This effect is enhanced by oxygen, temperature, the catalytic action of metals, oxidation and other factors. To confirm the influence of moisture content in oil on the deterioration of its properties, a statistical analysis of the oil sample test protocols was carried out. The obtained data allowed us to determine the moisture content as an important integral parameter of oil quality. Recommendations are given on the inclusion of a moisture content parameter in a set of mandatory requirements, in particular, for 10/0.4 kV consumer transformer substations equipped with silica gel air dryers