2022 IEEE International Conference on High Voltage Engineering and Application (ICHVE 2022)

This paper aims to study the effect of the breakdown behavior of mineral oil, synthetic esters, and natural esters in semi-uniform field electrode arrangement with a realistic degree of homogeneity of 0.2-0.3 under lightning impulse (LI) voltage with positive and negative voltage polarity. Furthermore, different stages of ageing will be analyzed. Finally, these results will be compared to the AC-breakdown voltage in uniform field according to VDE 0370-5:1996-03 to ascertain whether the easy to determine AC-breakdown voltage can be used to also compare the ageing behavior of the liquids.