Comparative Analysis of the Use of Mineral Oil and Vegetable Oil in Distribution Transformers

Abstract

The use of oil as dielectric insulator is a fundamental part of the operation and useful life of transformers. The most important function that a dielectric oil must develop is the cooling and dissipation of heat generated during the operation of transformers, being mineral oil the one traditionally used in this type of applications. However, nowadays vegetable oils have started to be developed, which are attractive due to their high biodegradability and flash point. This article is elaborated as follows: first, a brief description of the insulation used in the transformer is given. In the second part, the chemical, physical and electrical characteristics that a given oil must have in order to perform its function effectively are presented. Finally, an analysis of the heat transfer results of both types of oils is presented.