Electrical Treeing Simulations to Understand the Applicability of Needle-Plane Tests to Cables

Electrical treeing in lab-based testing currently requires the use of field enhancement points such as needle tips or thin wires. While these techniques produce reliable electrical tree growth, it is important to understand the limitations of such tests in the context of the different geometries found in high voltage assets. Here we apply Finite Element Analysis tools to investigate the consequences of using needle-plane geometries and to develop ideas on how treeing within a more uniform field may relate or differ. This work finds that local geometrical effects present in non-conductive trees in more uniform systems, responsible for variation in field magnitudes are unlikely to be replicated in needle-plane tests.