The frequency domain spectroscopy of natural ester and its impregnated paper insulation

With the advantages of high lighting temperature, easier degradation and renewable, the natural ester-paper insulation has been employed in distribution transformer, gradually. During the operation, the natural ester-paper insulation will deteriorate under the effect of hot, electrical field and moisture. So it is very important to assess the insulation status of ester-paper insulation in transformers. The Frequency Domain Spectroscopy (FDS) has been widely used to assess the insulation status of oil-paper insulation system. But there is little research about the FDS of natural ester and its impregnated paper insulation. This paper studies the influence of temperature and aging on the FDS of natural ester and its impregnated paper based on experiments. And the results show that, the temperature does not change the shape of FDS of natural ester and its impregnated paper, it just changes the position of FDS in the coordinate axis. The aging changes the shape of FDS of ester, obviously, but does not change the basic shape of FDS of ester-impregnated paper.