Spectral Characteristics of Acoustic Noise from Metallic Protrusions and Water Droplets in High Electric Fields

The spectral properties of acoustic noise generated by corona at imperfections and water droplets on high voltage transmission lines are studied by means of single site corona sources in a coaxial geometry. The steady state noise as generated by these metallic imperfections or spitters and by single, flow rate dependent, sites of water emission is recorded and analyzed by means of a high fidelity microphone and a recording wave analyzer. To insure isolation from ambient noise, the entire electrode structure used to generate the corona is contained in an anechoic chamber.