Showing papers by "John C. Fothergill published in 1981"
01 Oct 1981
TL;DR: In this paper, the authors report some interesting initial results from preliminary experimental and theoretical work relating all three subjects and conclude that treeing appears to be the most important physical long term pre-breakdown phenomenon that occurs in dielectrics due to the externally applied electric field.
Abstract: The probability of electrical breakdown in a stressed dielectric is related to the strength and time of application of the electric field. It is the aim of cable manufacturers to increase the dielectric field strength and service life without increasing the probability of failure. In this respect it is necessary to improve the quality of the insulation and prevent in-service degradation, without prohibitively increasing the cost of the product. A method which may achieve this in polymeric insulation without creating new chemical compos1t1ons is to alter the polymer morphology in such a way as to increase the “breakdown strength” and reduce the susceptibility of the material to “treeing”. Treeing appears to be the most important physical long term pre-breakdown phenomenon that occurs in dielectrics due to the externally applied electric field. Although these areas of study are obviously important, no generally accepted physical treeing model exists and there is little published work on the interrelationship between trees, electrical breakdown strength and polymer morphology. In this paper we report some interesting initial results from preliminary experimental and theoretical work relating all three subjects.
3 citations