Performance of HV transmission line insulators in desert conditions. IV. Study of insulators at a semicoastal site in the eastern region of Saudi Arabia

For pt.III see ibid., vol.6, p.429-38, Jan. 1991. Pollution buildup characteristics of various representative insulator designs were studied, and influential meteorological parameters were measured. Using the rapid flashover test technique, the electrical performance of naturally polluted insulators was assessed through laboratory investigations. The study revealed that considerably heavy pollution is experienced in Dhahran, Saudi Arabia, exceeding 0.1 mg/cm/sup 2/ in about ten months of natural exposure. The pollution contains sodium chloride and silica as the major soluble and insoluble ingredients. Insulator bottom surface geometry has a significant effect on pollution buildup, whereas the top surfaces behave almost identically with only a marginal influence in some cases. Prevailing desert meteorology characterized by limited rainfall, has a negligible self-cleaning effect on deep-ribbed insulators. Electrical performance assessed using the rapid flashover test technique gave different orders of merit based on equal-creepage and equal-height criteria among the tested insulators.>