Determination of criteria values for insulation systems based on natural esters

One of the most performing insulating systems is paper oil insulating system used mainly in high voltage and high power transformers. Hand in hand with the oncoming research on new liquid component of the paper oil insulating system of high voltage transformers it is necessary to establish new parameter criteria for such as systems. As standardized for mineral oil based systems currently used we need to establish limits of parameters for natural esters fluid as well. This paper deals with proposed possibilities of criteria establishing based on current standards and performed experiments.