Importance of Controlling Insulation Eccentricity and Cable Ovality for Extruded Extra High Voltage (EHV) Cables

Extra-High-Voltage (EHV) cables, defined as cables with voltage ratings ranging from 132kV to 400kV (Indian terminology), require exceptionally precise dimensional and geometric control to ensure dielectric integrity and long-term reliability. While insulation eccentricity receives significant attention during the manufacturing process, another critical geometric defect ovality remains a substantial factor contributing to electric field distortion, mechanical stresses, and installation challenges in EHV cable systems. This paper provides a comprehensive engineering analysis of eccentricity and ovality in XLPE-insulated EHV cables, focusing on their causes, measurement methods, resulting consequences, and mitigation strategies.