Influence of hydrogenated transformer oil on construction materials inside transformer

Modern transformers are composed of many kinds of insulation materials to form integral insulation system. To ensure a safe service, transformer oil should have excellent compatibility with insulation materials. In this work, the compatibility experiment between hydrogenated transformer oil and typical construction materials inside the transformer and the research on the influence of hydrogenated transformer oil on rubber seals, insulating paper and insulating varnish were performed. The results show that the hydrogenated transformer oil has good compatibility with the typical construction materials of transformer. The compatibility experiment of transformer oil and rubber seals presents that the degradation of naphthenic transformer oil is severer than hydrogenated transformer oil while the performance variation of rubber seals immersed in either of the oil samples is pretty small. The degradation of insulating paper immersed in naphthenic transformer oil is much stronger than in hydrogenated transformer oil after 28 days of aging, meanwhile the naphthenic transformer oil was also deteriorated more seriously than hydrogenated transformer oil. The naphthenic transformer oil has stronger solubility of insulating varnish by the analysis of GC-MS.