Electric field and potential distributions are crucial for their design, as they must withstand the potential difference between line conductors and grounded towers and also be free of electric discharges.
Their performance is significantly affected by weather conditions; raindrops, for example, result in the locally enhancement of the electric field strength, favoring, thus, the development of surface discharges.
In less than 7 minutes, the distributions of electric field and potential have been obtained.
The electric field and potential are getting higher as we get closer to the energized metal clamp. The “hot-spots”, where the electric field strength attains its highest values, have been restricted around the metal clamp.
In the case of a wet insulator, when raindrops are settled at its upper surface, the electric field distribution is distorted.