Dielectric response measurement on service-aged XLPE cables: From very low frequency to power frequency

摘要

Polymeric-insulated cables, especially cross-linked polyethylene (XLPE) cables, are widely used in power system transmission and distribution networks. A cable failure can result in lengthy outages and substantial economic loss to the electrical utilities. One of the primary reasons for cable fault is insulation degradation over the service time. Various onsite electrical, thermal or mechanical stresses can accelerate the aging process of power apparatus and curtail the lifetime [1]-[3]. Additionally, different chemical processes can alter the morphological structure or chemical composition of the insulating material and degrade the dielectric properties [3], [4]. Therefore, from economic and technical points of view, regular condition monitoring and diagnostic testing have become critically important for checking the health of the insulation system before the occurrence of any complete failure. Moreover, diagnostic testing performed at appropriate intervals coupled with proper maintenance helps extend the lifespan of high voltage power equipment and components [5]-[8].