Anomalous Noise Measurement and Analysis of the Valve Hall in ±800kV UHV Converter Station

In order to control the anomalous noise of the pole-I valve hall in a ±800kV UHV converter station, the background noise of the valve hall and the noise of each valve group in the valve tower are measured, respectively. The sound pressure level differences of the valve groups are compared. The anomalous noise locates in the short-circuit pipe of cooling water in the valve tower. Frequency spectrum analysis shows that the abnormal noise is related with the flow of cooling water. The two-dimensional finite element model is established to analyze the influence of chamfer angle and pipe length on the flow velocity of cooling water. The result shows that the abnormal noise is only related with the chamfer angle of the short-circuit pipe with constant flow velocity. The abnormal noise is successfully controlled by structure improvement of the short-circuit pipe and the potential risk to the valve group is avoided, which will give technique support to the operation and maintenance of the valve hall in UHV converter stations.