Effect of Thermal Aging on Threshold Field Strength and Relative Permittivity of Cross-Linked Polyethylene with Different Cross-Linking Agent Contents

This article presents the effect of thermal aging on threshold field strength and relative permittivity of cross-linked polyethylene (XLPE) with different cross-linking agent contents. Here, low-density polyethylene (LDPE) and dicumyl peroxide (DCP) are used as basic experimental material and cross-linking agent, respectively. Eventually, experimental results indicate that thermal aging can gradually make threshold field strength and relative permittivity of XLPE with different DCP contents increase and decrease, respectively. Besides, threshold field strength of XLPE with different DCP contents increases first and then decreases as the increase of DCP content, while relative permittivity of XLPE with different DCP contents decreases first and then increases as DCP content increases at different thermal aging time, etc. These studies in this article are the basis of the research on space charge accumulation and dissipation inside XLPE materials, which are of great significance to the normal operation of XLPE cables.