Trans-scale Evolution Mechanism of DC Electrical Breakdown Characteristics in Polyolefin Dielectrics

A common question that the classical breakdown theory mainly focuses on is the relation between electric breakdown strength and dielectric thickness. But the variation range of the sample thickness is limited. In this paper, a series of Low-density polyethylene (LDPE) slices with different thickness were used in DC breakdown test. Result shows that relation between DC breakdown strength and the thickness of LDPE is not simply in accordance with the inverse power law. This indicates that there exists critical thickness effect in the relation between the breakdown strength of LDPE and thickness.