Study of full scale UHV DC transmission line corona performance in corona cage

To study the corona performance of full scale UHV DC transmission line, a 4 m long, 2 m times 2 m corona cage has been constructed. At the same time, a corona performance measuring system consists of audible noise level meter, EMI receiver and ultraviolet imaging telescope has been set up too. Audible noise level, radio interference level and total of ultraviolet photon of a 4 times 500 mm 2 transmission line have been measured at different voltages. According to the test results, a method to determine the inception corona voltage of the full scale transmission line has been presented.