A Review on Alternative Oils as Dielectric Insulating Fluids on Power Transformer

Electrical insulation system are one of the factors that affects the distribution transformer operations. Conventionally, power and distribution transformer has been using mineral oil as its insulating material. Mineral oil is at a disadvantage in terms of poor biodegradability in the event of accidental spill causing contamination of water and soil. This strengthens the determinations to find a suitable substitute for mineral oil based transformer oil. For the past few years, there has been a growing concern in using vegetable oil. These fluids are currently being used in the range of small to medium distribution power transformers. Palm oil, Coconut oil, Canola oil and Rapeseed oil are an example of vegetable oil used as insulation oil. This paper describes the progress of vegetable oil as dielectric fluids by comparing the main properties to prove their potentials in order to replace mineral oil.