A Novel Approach to Estimate the Quantity of Ingressed Moisture Content Inside Metal Oxide Surge Arrester Using Dielectric Modulus Technique

In this article, a novel technique is proposed for the estimation of ingressed moisture content inside metal oxide surge arrester (MOSA) in service. For the estimation of ingressed moisture content inside a dielectric precisely, knowledge of frequency domain spectroscopy (FDS) characteristics can be useful. However, in traditional FDS measurement, dielectric relaxation characteristics cannot be properly understood due to electrode polarization effect. Therefore, to overcome this problem, dielectric modulus technique is applied in this work. Dielectric modulus can uncover the relaxation characteristics in a dielectric, which is obscured by electrode polarization effect. Therefore, frequency variation of complex dielectric modulus characteristics of MOSA at different ingressed moisture content is analysed using Havriliak-Negami (H-N) relaxation model to investigate the changes in dielectric relaxation behavior with moisture ingression. The findings of the paper reveal that empirically obtained relationship between ingressed moisture content and H-N model parameters can estimate the ingressed moisture content inside a MOSA with an acceptable accuracy.

Automated summary

A novel technique is proposed for estimating ingressed moisture content inside metal oxide surge arresters (MOSA), using dielectric modulus analysis to uncover relaxation characteristics obscured by electrode polarization effects. By analyzing the frequency variation of the complex dielectric modulus characteristics at different moisture content levels, changes in dielectric relaxation behavior with moisture ingression can be investigated. Empirically obtained relationships between ingressed moisture content and parameters of the Havriliak-Negami relaxation model can estimate ingressed moisture content inside a MOSA with acceptable accuracy.