Effects of Typical Adsorbents on Characteristic Gases Generated during Solid Insulation Dielectric Discharge in GIS

In order to reduce the influence of adsorbents on chemical diagnosis on insulation condition of solid organic dielectric in GIS, a creeping discharge model was set up on a apparatus to study the variation of target gases in different conditions, i.e., adding five different kinds of adsorbents (activated alumina, 3A, 5A, F-03 and KDHF-03) separately. The results showed that carbon-containing gases adsorption rates of different adsorbents were obviously smaller than the adsorption rates of sulfur-containing gases. The adsorption rate on COS was not more than 40%, and the other two kinds of carbon-containing gases (CF$_{\mathbf {4}}$ and CS$_{\mathbf {2}}$) were not affected by adsorbents or are weakly affected. The influence of adsorbents could be neglected to diagnose insulation defects related to organic dielectric, according to the growth of characteristic gas CF$_{\mathbf {4}}$ in GIS. In the presence of adsorbent, CS$_{\mathbf {2}}$ could be applied to judge whether the discharge is related to solid organic dielectric. The generation of COS indicated that the discharge level on the organic dielectric deepens, whereas the sensitivity of COS reflecting on creeping discharge level was decreased to some extent because of the influence of adsorbents. C(COS $+ \mathbf {CS} _{\mathbf {2}}$) /C(SO$_{\mathbf {2}} \mathbf {F} _{\mathbf {2}}$textbf), as a new diagnostic feature was proposed, had a positive relationship with the degree of discharge, which could effectively reduce the interference of adsorbents when diagnosing the seriousness of the discharge defects on solid organic dielectric in GIS.