Audible Noise Measurement of High-Voltage Transmission Lines Using Beamforming

Audible noise is crucial in designing and constructing high-voltage transmission lines. However, when measuring the audible noise of power lines, it is susceptible to interference from other noise sources in the external environment, posing significant challenges to data analysis and processing. To address the issue, we propose a method for measuring audible noise using a microphone array based on beamforming. We design filters using the FIR wideband beamforming algorithm and apply them to a single-direction incidence model. Filters designed using the phase iteration method are applied to a multidirection incidence model. Factors affecting beamformer accuracy and solutions have also been discussed. Simulation results demonstrate that both filters effectively suppress interference signals from other directions while preserving the desired direction signal. Experiments in a corona cage show that the beamforming filters can suppress external interference noise by more than 10.2 dB, validating the proposed algorithms and providing guidance to design high-voltage transmission lines in the future.