Analysis on the natural pollution characteristics of metal-oxide surge arrester with different external insulation material

In order to study the surface pollution distribution characteristics of the metal-oxide surge arrester (MOA) with different external insulation material, the polymer-housed MOA and the porcelain-housed MOA with room temperature vulcanized silicone rubber (RTV) were selected as research objects. After a one-year natural pollution accumulation, the equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD) of the MOA surface were measured, and then the surface pollution unevenness and the ratio of NSDD to ESDD at different positions of MOA were analyzed. The results show that the pollution of the high-voltage side and low-voltage side of MOA is more serious than that of the middle part. For the polymer-housed MOA, the average unevenness of ESDD and that of NSDD is about 1 and 2 respectively, and the average ratio of NSDD to ESDD of the top surface is about 9, while that of the bottom surface is about 4. For the Porcelain-housed MOA with RTV, both the average unevenness of ESDD and that of NSDD are about 1, and the average ratio of NSDD to ESDD of both the top and bottom surfaces is about 6. The research results can provide a reference for making the artificial pollution tests and improving the design level of the MOA.