Study on icing of energized insulators with AC service and electrical performance

In This work, laboratory investigations were carried out on 110 kV composite insulators, 7 units of an IEC standard suspension porcelain insulator string, and 7 units of a XWP-160 antipollution porcelain insulator string with 64 kV voltages in the multifunction artificial climate chamber of Chongqing University. Based on the test results, it puts forward that there are evident differences in ice accretion speed, ice density and ice structure between energized insulators and nonenergized insulators. The electrical field stress has an important influence on ice type and ice structure accrued on the insulators. Both flashover voltage and withstand voltage of the insulators covered with ice at an energized condition are higher than that at a nonenergized condition. Finally, it analyzes the factors that influence the ice type, structure and the flashover performance of an iced insulator.