Optimization of noise barriers in a ±500 kV switchyard: Field testing and numerical modelling

This study investigates noise characteristics of a ±500 kV high-voltage (HV) switchyard through field testing. Noise levels and spectral properties near the reactor and fence were analyzed. An acoustic boundary element method (BEM) model was developed to predict the reactor-generated noise. Using this model, the effects of fence height, the height and placement of an additional noise barrier on the combined noise reduction effects (NRE) were systematically examined. To further enhance the NRE, various top structures and sound-absorbing materials were applied to noise barriers, and their additional NREs were compared. The results indicate that increasing fence height by 1–2 m reduces the sound pressure levels (SPL) outside the fence by 1–5.8 dB. Adding L-type or T-type top structures further reduces SPLs by 0.4–4.6 dB. Installing an additional erect noise barrier between the reactor and fence reduces SPLs by 1.4–8.8 dB, with the insertion loss (IL) increasing by 0.6–2.8 dB per 1-m barrier height increase. The T-type or Y-type top structures on the barriers also reduce SPLs by 0.4–4.6 dB, while traditional sound-absorbing materials have minimal impact on the NRE.