Investigation of Electrical Characteristics of Mixed Insulating Liquids for their Use in Electrical Power Equipments

It has been seen that, mineral oil is the most widely used insulting liquid in the world today because of the wide availability and low cost. However, poor biodegradability and limited reserves of mineral oil has promoted the development of environment friendly insulating liquids. Natural and synthetic esters are considered as potential candidates to replace mineral oil in electrical equipments. Both natural and synthetic esters are fully biodegradable, less toxic and less flammable. But their high cost and availability has limited their use in special applications today. The aim of this paper is to investigate typical electrical characteristics of mixture of mineral oil with biodegradable synthetic oil. This new mixed insulating liquid will be proposed as alternative to mineral oil with lower environmental risk and comparatively lower cost of insulating liquids that has higher biodegradability.