Corona Audible Noise Measurements in a Small Indoor Corona Cage under HVDC Voltages

Corona audible noise measurements were carried out in a small indoor corona cage under DC fields and dry conditions. The aim of the experiments was to determine possible audible noise levels under local climatic conditions. The variation between the corona audible noise and the static conductor surface gradient was investigated for stranded aluminium conductors. The results obtained were compared with the EPRI, CRIEPI and BPA predictions generated from the EPRI ACDC line software. The results demonstrated good agreement with the predictions in terms of trends.