Influence of profiles on DC insulator performance under pollutedconditions

摘要

A dynamic model is used to investigate the effect of insulatorprofiles on DC pollution flashover voltage. The purpose is to aid in thedesign of insulators by supplementing laboratory and field measurementsby an analytical model. The model computes the pollution flashovervoltage (FOV) for a given degree of salinity by simulating the arcpropagation along the leakage path. The change in the arc resistance andother quantities are calculated dynamically. It is observed thatinsulators with alternate long and short underribs and a wider gapbetween the rib tips have higher FOVs than other designs. It is seenthat the influence of diameter on the FOV and hence on mm/kV isappreciable irrespective of the type of profile