Application of Kirchhoff formula in prediction of noise level of substation

摘要

The noise source and its characteristics of existing substation are analyzed, and the meaning and physical meaning of Kirchhoff formula are described. The Kirchhoff formula is a very effective method and tool for solving the problem of closed cavity radiation noise with complex shapes in engineering practice. For any complex acoustic surface, the Kirchhoff formula can be used to obtain the radiation field distribution of the surface in space as long as the sound pressure and vibration velocity on the surface are known. In the noise analysis of the substation, as long as the sound pressure level on the surface of the transformer is known, the theoretical prediction of the radiation noise in the substation can be realized. The noise level of a 110kV outdoor substation is estimated by Kirchhoff formula, and the results of this method are compared with the actual measurement results. The results show that the measured results are in good agreement with the Kirchhoff formula, which proves the accuracy and efficiency of the method, so that the method can be used to guide the design and construction of the actual substation.