Time-domain performance of audible noise for positive dc corona: Numerical simulations and measurements

Corona-generated audible noise of HVDC transmission lines is a paramount parameter for design consideration. An acoustic source model and a computational technique are proposed to simulate the sound pressure pulse of positive dc corona discharge. A reduced-scale experimental platform with artificial defeat conductor is built up to verify this numerical method and used to study the time-domain characteristics of the audible noise of the single, three and five corona sources, respectively. The measured and computational results show that calculations of sound pressure are reasonable agreement with the measurements. The repetition frequency of the audible noise pulses increases more significantly than their amplitude, as the number of the corona discharge points increase. Furthermore, with the increase of the applied voltage, the repetition frequency and amplitude of the audible noise pulses increases.