Electrical breakdown and space‐charge effect in polyphenylene sulfide films

AbstractElectrical breakdown of polyphenylene sulfide (PPS) films, one of the high‐temperature engineering plastics, has been investigated. The results show that the dc breakdown strength is lower than the impulse one, and that the difference in electric strength between dc and impulse becomes wider as the sample thickness decreases. The result suggests space‐charge accumulation when dc voltage is applied.Further, the impulse breakdown strength in the presence of a dc prestressing voltage is measured in order to elucidate the space‐charge effect. The data on the contribution of the prestress voltage to electrical breakdown are used to estimate the amount of space charge accumulated in the specimen during the dc prestressing.