PROJECT TITLE :

Numerical and experimental investigation of the effects of pollution on glass suspension-type insulators

ABSTRACT:

This study presents each numerical and experimental results regarding the effects of pollution on the flashover performance of glass suspension-type insulators. The finite part method (FEM) was used for simulating polluted insulators both at power frequency and at lightning impulse voltages. Partially conductive epoxy resin with graphite powder was used for modeling pollution on the insulators, that enabled the measurement of the electrical potentials on the polluted insulators. Numerical studies demonstrated the variations in the sphere distributions caused by the placement and severity of the pollution as well as by the type of voltage applied. The simulations, that were verified to a degree through measurement, showed that pollution conductivities larger than 10-6 S/m and ten-3 S/m alter field distributions for power frequency and lightning impulse voltages, respectively. Unlike the results obtained for partially polluted insulators, the voltage distribution was nearly linear for fully polluted insulators. Experimental studies revealed that the placement of the partial pollution plays an important role in flashover performance for lightning impulse voltages however incorporates a negligible result for power frequency voltages.