Studies of DC conductor corona in a small corona cage

The complex nature of corona phenomena, combined with the number of factors influencing these effects, make experimental studies indispensable for evaluating the corona performance of transmission lines. Different methods, ranging from tests in laboratory cages to measurements on operational transmission lines, may be used for obtaining the necessary data. This paper gives a brief introduction to the design of a small corona cage as well as presenting test results obtained from the cage at the HVDC center of the University of Durban-Westville. These tests involved changing the surface conditions of conductors in order to determine their corona performance.