Measurement and analysis of sound radiation from coherently vibrating shunt reactors

In parallel with the rapid development of ultra-high voltage (UHV) power transmission systems, noise contamination radiated from UHV shunt reactors is becoming an urgent concern. This investigation explored the distributed structural vibration of reactors and their near-field and far-field sound radiation characteristics based on a thorough on-site measurement and a combined numerical method. The proposed method could realize sound field reconstruction of on-site shunt reactors by directly measuring their surface vibration, thus avoiding complex modelling with fluid-structure interactions and multi-physics problems. Furthermore, the combined method was utilized to investigate the effect of acoustical environments upon reactors' sound radiation. The results show that reflection boundaries composed of firewalls among reactor units could introduce a higher noise level in the parallel radiation region due to their influence on the sound source directivity. Finally, the sound power levels of the on-site reactors were derived from the constructed sound field, which could avoid on-site background noise concerns in the current executive standards.