Simulation of mechanical pressure of XLPE-SiR interface in cable joints based on operating temperature and interference parameters

Composite interface between XLPE insulation and SiR insulation is the weakest region of cable joints. Interfacial pressure is one of the paramount factors to ensure interfacial insulating strength and sealing strength, and to ensure the stable operation of cable lines. Interfacial pressure depends on the material parameters, structural parameters and environmental parameters, of which temperature and interference are the two most important factors. Nowadays, researches on the calculation and measurement of interfacial pressure are not in-depth, and power grid enterprises lack relevant tests and standards, which pose great challenges to the design and quality control of cable accessories. In this paper, a theoretical calculation method for the interfacial pressure of XLPE-SiR interface is proposed and verified by finite element simulation. The influence characteristics and mechanisms of operating temperature and interference parameters on interfacial pressure are analyzed, so as to provide reference and guidance for the design and selection of cable accessories.