Audible Noise Characters Analysis of 220kV Xiangtang Transmission Line

In order to know the corona audible noise characters of the 220kV transmission line and its influences on nearby residents' life, we measured the corona discharge UV-light, the environmental noise and sound energy of the transmission line respectively. The study results showed that the corona discharge occurred at the transmission line. The audible noise sound level on the roof was 46.2dB(A) at night, that was slightly beyond the limit value of the first zone of Sound Environment Quality Standard. At night, the transmission line audible noise like 'SiSi' was so obvious that disturbs residents. The sound energy analysis results showed that the transmission line audible noise energy focused on the frequency range below 200Hz. The directivity study of sound intensity showed that the highest sound energy happened at 100 Hz in the direction from the transmission line to the top floor of the residents' house, in which explains that the transmission line noise, slightly beyond the limit, is obvious.