FORECASTING ELECTRICAL ARCS INSIDE THE TANK OF A POWER OIL-FILLED TRANSFORMER

The article, citing the works of various authors, presents the causes of damage to oil-filled power transformers. The article lists the main causes of damage to electrical equipment due to the poor quality of technical diagnostics. For example, high-voltage tests of winding insulation and cable lines can lead to incomplete breakdowns. The article formulates five characteristics of partial discharges, which, under certain conditions, can develop into an electric arc with damage to transformers. Replacing oil-filled bushings with bushings with RIP insulation did not improve the reliability of transformers. The article notes that repeated failures of bushings with RIP insulation occur in the Belarusian power industry. For the first time, a hypothesis is put forward that the cause of ongoing damage to oil-filled power transformers is an electric arc inside the transformer tank. The article formulates the physical similarity between an electric discharge in the atmosphere and in the tank of an oil-filled transformer. A methodology for studying an electric arc in a transformer tank is proposed. The results of leakage current measurements in the grounding buses of power transformers are presented. It is noted that to predict electric arcing in transformer oil, it is advisable to monitor the oil quality, changes in the hydrogen content of the oil, increases in grounding bus current, and increases in partial discharges in the grounding buses using specialized sensors.

transformer, oil, partial discharges, local overheating, electric arc, ignition of bushings, tank rupture, transformer model, prediction, grounding busbars.

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2026-04-03