Aging and life control of cross-linked polyethylene as cable insulation material

Abstract

Cross-linked polyethylene (XLPE) has been widely applied in the field of power cables because of its excellent mechanical properties and insulating properties. However, during the operation of high voltage cables, XLPE will inevitably be affected by electrical aging, thermal aging and electric-thermal joint aging, which makes the performance and life of the material decline. Therefore, it is necessary to enhance the aging resistance of XLPE without affecting its mechanical properties and insulating properties, so as to achieve the purpose of extending its service life. In this paper, the structural characteristics and cross-linking mechanism of XLPE are introduced, the aging process and influencing mechanism are systematically analyzed, and the life decay problems of XLPE due to aging are explored by using methods such as the temperature Arrhenius equation and the inverse power law of voltage. The regulatory strategies such as grafting, blending, and nano-particle modification, etc., can be applied to improve the thermal stability, antioxidant performance, and thermal aging resistance of XLPE, thereby extending its service life. Finally, the future direction of the strategies for regulating the service life of XLPE cable insulation materials is envisioned, which provides theoretical guidance for the further improvement and long-term stable operation of XLPE cable insulation materials.