The Study on Discharge Characteristics and Influencing Factors of Bird Dropping Hazards in Overhead Transmission Lines

Bird-related hazards are one of the main causes of operational failures in overhead transmission lines. These hazards encompass bird droppings, bird nests, and bird activities, with bird dropping hazards receiving the most attention due to their high occurrence rate and severe consequences. This paper distinguishes bird dropping hazards from insulator contamination by highlighting a key feature: bird droppings tend to hang on the edge of the insulator sheds, partially bridging the air insulation between the sheds. Based on this distinction, the study investigates the characteristics of electric field distortion caused by bird droppings hanging on the insulator sheds through modeling and simulation. Additionally, simulating this phenomenon, an experimental study was conducted using fully wetted cloth strips as an equivalent to hanging bird droppings. The discharge characteristics of the bird droppings were analyzed, and the range of discharge characteristic parameters was determined. The study also considered the impact of the volume and salt content of the simulated bird droppings on the discharge behavior.