Electric field analysis and structure design of the box of bird guard used in 220 kV transmission line

Bird activities including the defecation, nesting, and flight are easy to cause electrical faults of overhead transmission lines, study on the prevention measures of bird damage to transmission lines is of great significance to ensure the stable and reliable operation of the power system. With the establishment of finite element simulation model, the effects of box of bird guard with different material on the electric field and potential distribution on transmission line insulators are studied. Besides, combined with the theory of air discharge and the results of simulation, the influence of rainwater on the air gap around the insulator breakdown characteristics is studied when the water is drained from a scupper at the bottom of the box of bird guard, and a reasonable design scheme for the box of bird guard scupper is proposed. The research results here can provide a guidance for the selection and key parameters’ design of the box of bird guard.