Corona ring design for a 400 kV non-ceramic insulator

In this paper, a corona ring design for a 400 KV non-ceramic overhead line insulator used in Abu Dhabi Transmission and Dispatch Company (TRANSCO) was simulated using COMSOL Multiphysics software. Three parameter were changed during the investigation which are: the ring diameter (R), the diameter of the ring tube (r) and the vertical position of the ring along the insulator (H). A simple criterion was used to choose the desired dimension of the corona ring which is finding the maximum electric field along the insulator surface and corona ring surface and making sure it is below the corona inception level. According to that, the dimensions and the position of the corona ring can be chosen. The corona ring design was simulated for both ends of the insulator, energized end and ground end. Moreover, a comparison between a single corona ring and double corona rings around the energized-end was made.