Development of a natural ester liquid with significantly enhanced dielectric characteristics

Natural ester (NE) dielectric liquids have different physical and dielectric properties compared to mineral oil. For the design of power transformers with natural esters, such differences have to be addressed with appropriate changes in the design rules. This article reports the laboratory development of a novel natural ester liquid formulation that has significantly enhanced breakdown and acceleration voltages under non-uniform electric field geometries and at large electrode gaps. Considering the other relevant properties of this new liquid formulation for transformer applications, there is probably a scope to design environment-friendly power transformers at higher voltages and power ratings without significant modifications in the transformer design rules.