Thermal Behavior Analyses of a Polymeric Surge Arrester by Computer Simulations

Zinc oxide (ZnO) based surge arresters are applied in electric power systems and provide protection for transmission lines and power equipment. During the occurrence of lightning or switching surges, a voltage level above the equipment insulation level can be reached. A defective arrester may not be able to provide the proper protection level in substations, exposing the equipment and personnel to damage. Electrically, an arrester, properly working, is able to limit this voltage level avoiding damages to the protected equipment. And, thermally, a surge arrester, in good condition, should be able to deal with the surge current by absorbing its energy and dissipating it to the environment. Otherwise, if the arrester presents some problem or if it is not correctly dimensioned, it can be lead…