A stochastic model for contact surfaces at polymer interfaces subjected to an electrical field

摘要

Morphology of the contact area between solid insulation materials ultimately determines the short-and longterm electrical properties of the complete insulation system. The main purpose of this paper is to propose a statistical model to examine the real area of contact between solid dielectric surfaces and secondly to verify and correlate the model outputs with experiments. The model computes real area of contact, number of contact spots and average cavity size at the interface as a function of elasticity, contact force and surface roughness. Then, using the average cavity size and the Paschen's law, the discharge inception field of the cavity (CDIE) is estimated. AC breakdown strength (BDS) testing of solid-solid interfaces was carried out, where cross-linked polyethylene (XLPE) samples with four different surface roughnesses were tested at various contact pressures.