Multi-layer Constrained Damping Sound-insulation Technology for Low-frequency Noise Control of Transformers
Low frequency noise of transformers is complained very often by residents around the substation.In order to effectively block the transmission of noise outside the transformer oil tank,this paper develops a multi-layer constrained damping sound insulation plate on the basis of testing and mastering the noise level and spectrum characteristics of a 500 kV transformer.Firstly,the simulation analysis model of the sound insulation plate is constructed,and the influence of the constrained layer material and the elastic core material on the sound insulation performance is calculated and analyzed.Then,the structural parameters of the multi-layer constrained damping sound insulation plate are determined by the sound transmission loss test.Finally,the sound field simulation models of the 500 kV transformer and the multi-layer constrained damping sound insulation plate are built and verified by an actual transformer respectively.The results show that the sound pressure level of the transformer decreases by 9.3 dB(A)after the installation of multi-layer constrained damping sound insulation plate.