A study of correlation between the ect and ehd properties of different aged insulating oil mixtures that can Be an alternative to mineral oil for the insulation and cooling of power transformers.

This article presents the hypothetical steps leading to the damage of power transformers in order to examine whether there is a correlation between the electrostatic properties (ECT) and the electro-hydrodynamic properties (EHD) of insulating oils. Vegetable oils such as, olive oil (OO) and sunflower oil (SO) have been tested as alternative oils for the insulation and cooling of transformers and their blends with naphthenic mineral oil (MO) on the basis of well-defined ratios and for a remarkable aging time, which is an original contribution and insight offered by this paper. The results obtained for the different mixtures with regard to the electrostatic properties and the electro-hydrodynamic properties as well as the physico-chemical properties (power factor "tgδ", resistivity, conductivity and viscosity) in terms of the aging time were compared with that of the mineral oil.

Studies of different types of insulating oils and their mixtures as an alternative to mineral oil for cooling power transformers.

Because of their availability and low cost, mineral oils have been widely used for a long time in power transformers to allow their insulation and cooling. However, their low fire safety and low biodegradability potential have made it necessary to look for other insulating liquids as an alternative to this mineral oil used in high voltage electrical equipment. This work presents an experimental study to compare between the physicochemical characteristics of mineral oil, olive oil, sunflower oil and different oil mixtures.