On calculating surface potential gradient of overhead line conductors

The surface potential gradient is a critical design parameter for planning overhead lines, as it determines the level of corona loss (CL), radio interference (RI), and audible noise (AN). The majority of existing models for surface gradient calculation are based on analytical methods which restrict their application in simulating complex surface geometry. This article proposes a novel method which utilizes both analytical and numerical procedures to predict the surface gradient. One of UK National Grid's transmission line configurations has been selected as an example to compare the results for different methods. The different stranding shapes are a key variable in determining dry surface fields.