Audible Noise and Corona Loss Performance of 9-Conductor Bundle for UHV Transmission Lines

This paper summarizes the test results of a single-phase line of the 9 x 30.8 mm conductor bundle, supported in a symmetrical 1.22 m diameter circle. Statistical analyses of long-term audible noise and corona loss data for a variety of weather conditions and at line-to-ground test voltages of 815, 890 and 975 kV are presented, including the corona effects as function of rain rate. Extrapolations of single-phase test results to evaluate the audible noise and corona loss performance of an assumed three-phase line are also discussed.