BEHAVIOR OF LONG INSULATOR STRINGS IN DRY CONDITIONS

The behavior of long insulator strings under switching and lightning impulses and AC voltage is studied up to 750 kV. With increasing short-circuit currents, it is necessary to fix the spark between specially designed electrodes in order to preserve other metallic pieces from the thermal effects of the arc. Therefore, the influences of the shape of the fittings, of the insulators and of the environment of the string are examined not only with regard to the flashover voltage but also to the discharge development. Moreover, data for design purposes are given on the basis of the gap-factor concept. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc.