Requirements and Expectations of Natural Ester Fluids for Application in Power Transformers

Natural ester seed oil is a biodegradable fluid that is increasingly being used as a replacement for mineral oil and for high temperature flashpoint liquids, including silicone and RTEMP. This paper addresses technical issues that need to be answered in introducing a new dielectric insulating and cooling fluid for distribution and power transformers. The author´s experience and training in large power high voltage transformers gives him particular insight into the dielectric, thermal, and physical issues that must be addressed