Indoor substation low-noise design and sound absorbing structure improvement considering power transformer acoustic radiation characteristics

Abstract To decrease the influence of indoor substation noise originating from power transformers in the surrounding soundscape, an improved indoor substation low-noise design procedure was proposed and demonstrated in this study. According to the new design procedure, acoustic radiation characteristics analyses were conducted to quantify and visualize the external sound field of a power transformer. The interdepartmental and intradepartmental feedback was then summarized from the indoor substation noise radiation level measurements. Finally, these acoustic radiation characteristics analysis results and feedback were applied to the low-noise indoor substation redesign in both the integrated layout modifications and sound absorbing structure improvements to decrease the sound pressure levels at the noise sensitive area boundaries. The comparative analysis results verified that, on the premise of land cost neutrality, the modified layout and sound absorbing structure could limit the substation noise impact on the surrounding soundscape, and the mean value of the maximum sound pressure levels at the noise sensitive area boundaries were 6.6 dBA smaller than before.