Electrical Behaviour of Ester-Based Dielectric Liquids for Use in Transmission Transformers

The use of alternative dielectric liquids is on the rise, with fire safety and environmental concerns at the forefront for the switch from mineral oil. Ester-based dielectric liquids have been in use in the power industry for almost four decades, with synthetic esters having originally been introduced as replacements for harmful PCBs in the late 1970s.