Analysis of Long-term Measured Data of Audible Noise on UHV AC Double-circuit Transmission Lines on the Same Tower

Abstract

In order to obtain the level and characteristics of audible noise from actual UHV AC double-circuit transmission lines on the same tower in operation, the long-term observation station for electromagnetic environment was established near 1 000 kV Huainan-Shanghai UHV AC double-circuit transmission lines on the same tower in Wuhu, Anhui Province. Typical spectra under different weather conditions and the of audible noise during rainy days were obtained for ten months. The results show that the data of audible noise during rainy days from the three measure points in Wuhu observation station conform to normal distribution, and the A-weighted level of audible noise and its 8 kHz components at 20 m away from the projection of outside phase have a good correlation. The L50 audible noise level during rainy days at 10 m and 20 m away from the projection of outside phase are 49.83 dB and 49.58 dB, respectively, which are in consistent with the calculation by using BPA method minus 2 dB.