An investigation of self-repair systems for solid extruded polymeric and fluid filled cables

There have been recent remarkable developments in self-healing chemistries for polymeric materials. These hold great promise for self-healing electrical insulation systems, which can confer self-healing functionality in a variety of power generation and transmission applications. A particular area of interest is undergrounded power cables, as failure in these systems can be very costly, and damage is difficult to detect and preventative maintenance often impossible. This paper will review a number of different approaches to self-healing fluid and solid systems with an emphasis on mechanisms that can support self-repair processes. These principles provide a basis to apply the concepts to a variety of electrical insulation systems. We illustrate the approach by reference to recent work on the development of self-repair systems for fluid-filled cables subject to sheath damage and oil circuit leakage and polymeric cable sub-sheath repair systems, designed to restore sheath integrity and prevent the intrusion of water. The paper will conclude by underlining the importance of linking self-repair function to insulation system design and illustrate this for the case of power cables.