Dielectric performance of solid dielectric immersed in vegetable oil with antioxidant

Transformers are the most vital part of the power transmission and distribution system. Protecting them from all possible abnormalities is of very high priority. The insulation levels in the transformers need to be of very high grade as the power and voltage levels of a transformer are very high. Transformers are generally filled with petroleum based mineral oil as an insulator and also as a coolant inside them. These oils are highly inflammable and also highly toxic. They are also non-biodegradable, causing major harm to the environment. Vegetable oils which are abundant in nature unlike the mineral oil is being studied as a suitable substitute for mineral oils as transformer oil. The availability of vegetable oils differ from place to place. The work here focusses on the commercially available vegetable oils in India. Seven different samples of oil are tested for their dielectric properties and viscosity and the best one among them is tested with a solid dielectric (epoxy) immersed within it in order to simulate more appropriate conditions of a practical transformer. The tests are conducted based on Indian Standards (IS6792).