Improving Transmission Line Gap Insulation Performance Using Polyurea Coatings: An Experimental Study With Copper Rod Simulations of Bird Droppings

Advancements in power systems and the rising demand for high power quality have heightened the focus on transmission line safety and stability to ensure safe and efficient energy system operation. However, high‐voltage transmission line towers are susceptible to bird‐related damage, leading to flashover faults and even power outages. This study adopts an experimental methodology, using copper rods as surrogates for bird droppings, to investigate the effectiveness of two‐component polyurea materials in improving the gap insulation performance under bird‐related conditions. Polyurea coatings were applied to the high‐ and ground‐potential sides in three different insulation configurations: insulation on both the high‐ and ground‐potential sides, insulation only on the high‐potential side, and insulation only on the ground‐potential side. Electric‐field distribution simulations and alternating current breakdown tests revealed that, compared with the configuration without local insulation, those with polyurea coatings optimise the electric‐field distribution, enhance the insulation reliability, widen the gap's safety margin and increase the breakdown voltage. Among the tested configurations, the one with polyurea coatings on the high‐ and ground‐potential sides demonstrated the best insulation performance, substantially increasing gap breakdown voltage. These experimental findings confirm the reliability of polyurea materials in improving transmission line insulation, offering new insights and an experimental foundation for further research aimed at enhancing insulation reliability and safety in transmission systems.