Role of electrical insulation in the design and operation of high voltage equipment

Electrical insulation is key for all high-voltage equipment. The insulation design factors are summarized for major high-voltage equipment for generation and transmission systems, including generators, capacitors, transformers, underground transmission cables, and gas-insulated equipment. Recent developments of new insulation systems have resulted in significantly improved systems, including enhanced performance, improved manufacturability, reduced size and cost, and extended operational life. The impact of these developments and the future directions of new insulation systems are discussed for each system. It is emphasized that to appreciate the full technical and economic impact of changing the insulation, one needs to consider not just the component, but the complete, installed and operational system.