Abstract :
PROM published records of flashovers on double-circuit towers which have tripped out both circuits, and from opinions expressed by operating engineers of various power companies, approximately 20 per cent of faults occurring on double-circuit towers involve conductors of both circuits. In addition to these, instances have been reported where faults in substations have involved conductors of circuits not on the same towers. “It seems worth while therefore,” states Edith Clarke (A´23) of the General Electric Company, Schenectady, N. Y., in a current A.I.E.E. paper, “to have in convenient form, methods for calculating short-circuit currents, and of determining the stability limit of a system when faults occur simultaneously at two separate and distinct points of the system.”
