Characteristic And Inversion Method Of Noise Sources In HVDC Converter Stations

The high-voltage converter station is the key node in the HVDC transmission project to complete the AC-DC conversion,adjust the operating state of the system,and ensure the safe and stable operation of the system.During the operation of the converter station,the equipment such as converter transformers,valve cooling systems,smoothing reactors,and AC/DC filters will generate noise,which will have an impact on the staff inside the station and the surrounding environment outside the station.With the improvement of voltage level and transmission capacity,the noise problem of converter stations becomes more and more prominent,which has become an important factor to be considered in the planning and construction of HVDC projects.Therefore,it is of great significance to study the characteristic and inversion method of the noise source of high-voltage converter station,so as to obtain the sound source parameters under the actual operation of the equipment,which is of great significance to the effective management of noise inside converter station and the security and stability of the power grid.In this paper,by analyzing the noise characteristics of the main sound source equipment in the high-voltage converter station,the inversion method of the sound power spectrum of the noise source of the converter station and its engineering application are studied based on the engineering calculation method of outdoor noise propagation.This article includes the following:(1)According to the measured data,the characteristic of the noise of the main noise source equipment in the high-voltage converter station were studied.Based on the large amount of noise data measured in the field,the sound mechanism of the converter transformer,the smoothing reactor,the valve cooling system,and the AC/DC filter were studied.The noise's spectral characteristic of each sound source was analyzed,and the timbre characteristic of the noise of each sound source were counted based on timbre parameters.What's more,the characteristic timbre parameter of the noise of each sound source were obtained,and the noise's characteristic of each sound source is characterized from the perspective of timbre.(2)Based on the engineering algorithm of outdoor sound propagation,the calculation method of the noise propagation inside the converter station was studied.On the base of the principle of sound source equivalence was given,the calculation method of outdoor sound field is expounded with the point source as the research object.Furthermore,the calculation of the noise attenuation and sound wave reflection in the method were analyzed in detail,and the synthesis algorithm of multiple sound source sound field was presented.(3)An inverse calculation method of sound source sound power spectrum based on the field measured data in converter station was proposed.The single source sound power spectrum inversion model and multi-source sound power spectrum inversion model are constructed respectively,and the respective inversion steps are described in detail.By using iterative Tikhonov regularization method,the stable solution of the mathematical model of sound power spectrum inversion for multiple sound sources was realized.(4)The accuracy and engineering applicability of the proposed sound source sound power spectrum inversion algorithm were verified by engineering application.According to the actual project,the sound source equivalent model of each main sound source in the station were established.On this basis,the proposed inversion algorithm was used to calculate the sound power spectrum of the main sound sources in the station.The sound field around the sound source is calculated by using the sound power spectrum of the sound source as the sound source parameter,and the accuracy of the inversion result was verified according to the measured data.Through the application in other converter stations,the applicability of the inversion algorithm was verified.