Flashover performance of 380 kV V-strings with composite insulators under lightning and switching impulses

This study presents simulation and experimental test results regarding potential and electrical field distribution along 380 kV V-strings in Turkish national electric power transmission system which are composed of silicon-rubber insulators. A two-dimensional (Electro 2D) and a three-dimensional (Coulomb 3D) simulation programs are used for transient and electrostatic field calculations, respectively. Simulations are conducted only for clean insulators under dry conditions. The effects corona rings and types, lengths of conductors, conductor sags, protection lines, phase conductors, tower configurations and arc distances on the field distributions are analyzed. Experimental studies are conducted at Fuat Kulunk High Voltage Laboratory of Istanbul Technical University.