Preparation and Characterization of Chemically Modified Vegetable Oils as Liquid Insulation in Transformers

Due to demand for development of sustainable alternative liquid insulation for transformers, vegetable oils have attracted many researchers as potential substitute to traditionally used mineral oil. Even though vegetable oils have better dielectric characteristics, they have some demerits related to its flow nature due to presence of fatty acid content in it. In this work, it is proposed to study the characteristics and analyze the suitability of crude and refined form of ground nut oil and gingelly oil as liquid insulation after processing for removal the fatty acid components. For removing the fatty acid content from investigating oil samples, transesterification process is adopted in this work. Suitability of oil samples are investigated with measurement of the properties related to flow characteristics (viscosity and pour point), electrical characteristic (breakdown voltage) and thermal flammability characteristic (flash point). The investigation reveals that the investigated vegetable oil samples have necessary characteristics to be an alternative to traditional transformer oil in future.