Switching Surge Duty of Metal Oxide Surge Arresters in Multi-Phases´ System and Its Equivalent Conditions in a Test

Switching surge duty test imposing the highest power dissipation on high voltage metal oxide arresters has usually been done with a single phase circuit due to the limit of test facilities, in spite of complex multi-phases in a service system. The purpose of this paper is to propose new equivalent line constants and reasonable conditions of charging voltage in a test circuit, which were derived from the application study of surge arresters on double circuits and transposed 500kV lines. So-called positive, negative, zero, self and mutual mode impedances are not equivalent. Other impedances must be used and some correctiorts for charging voltage are required in a transmission line discharge test.