Design parameters of weathersheds that affect the ageing of polymer insulators in salt-fog

The paper presents the results of a study in which the third harmonic frequency component of leakage current is used to study various design parameters of weathersheds that affect the ageing of polymer insulators in salt-fog. Salt-fog was applied to model insulators for 120 hours at two different conductivity levels, i.e. 1000 /spl mu/S/cm and 2000 /spl mu/S/cm as an aging test. The effect of the number of sheds and shed inclination angle on the aging performance of polymer insulators was studied. Model insulators having 2-sheds showed better performance than 4-sheds. Also, the shed inclination angle improved the performance of the insulators in salt-fog.