The Effect of Temperature and Humidity on Corona Performance of UHV DC Transmission Line

To research the effect of temperature and humidity on corona performance of UHV DC transmission line, a mini corona cage has been constructed and put in a manual environment room, which temperature and humidity can be controlled. At the same time, a corona performance measuring system by using vary methods such as current impule method, acoustic method have been set up too. The corona inception corona voltage gradient of a copper line have been measured in a mini corona cage not only at different absolute humidity from 3 g/m³ to 12 g/m³ but also at different temperature from 0degC to 35degC . The relationship between inception corona voltage gradient and temperature and humidity have been achieved.