The effects of steep-front, short-duration impulses on powerdistribution components

A line-type pulser has been developed to test the effects of steep-front, short-duration (SFSD) pulses on distribution components. The risetime is 50-100 ns and the pulse duration is on the order of 300 ns. Terminators often shattered or punctured rather than flashing over. The insulator flashover voltage is approximately 1.5 times CFO for standard lightning impulses. Arresters exhibit an inductive character, with the SFSD peak voltage at 10 kA approximately 4-5 times the 8-pulse×20-μs 10 kA discharge voltage. Polyethylene insulated cable has a characteristic degradation in which failure voltage decreases with number of SFSD pulses