Study of the vegetal oil as a substitute for mineral oils in distribution transformer

There are so many factors that negatively affect distribution transformer operations, especially its electrical insulation system. Traditionally mineral oil has been used as insulating material, however, in the last years there is a growing interest in using vegetable oil, these fluids are currently being used in the range of small to medium distribution power transformers. The purpose of this work is to determine distribution transformer performance using natural ester dielectric fluid compared to those with standard mineral oil. The most significant factor that affects insulation material deterioration is temperature increments due to overload. We used the ASTM standard test method for analysis of gases dissolved in electrical insulating oil, to assess the aging of transformer insulation paper in natural ester dielectric fluid compared to that in conventional transformer oil. The results showed that distribution transformers using vegetable oil has a useful life longer than others using mineral oil, roughly 42,86 percent.