Degradation analysis of mineral oil in an oil-immersed ZnO-basedsurge arrester

摘要

In this work the degradation of transformer mineral oil inoil-immersed ZnO-based surge arresters has been studied. Three differentkinds of ZnO varistors: 1-non-coated, 2-resin-coated and 3-glass-coated,have been used in this study. It can be seen that after long-period highthermal constraints in oil there is a deposited layer on the varistors'surface which call disturb the function of the non-coated varistors. Itis also observed that the ZnO varistor and its coating have an influenceon degradation of the oil