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Study on Audible Noise Characteristics of Filter Capacitors and Reactors in HVDC Converter Stations by Using Sound Signal Processing Array Technique

Compared with AC substation, DC substation incorporates more kinds of electrical devices emitting high level of noise, which leads to more complicated acoustic filed and exerts negative influences to ambient environment and residents. Filter capacitors and reactors reveal to be the main noise sources in HVDC converter stations. In order to control and restrict the noise emission, it is necessary to study the noise characteristics of filter capacitor and reactor and figure out the maximum noise contribution. In this paper, the noise generating mechanism of AC filter capacitor and reactor are theoretical introduced firstly. Then the sound signal processing array technique based on beam forming algorithm is investigated and applied to build the noise positioning and measurement system. By applying the novel system to measure and positioning the noise emission in different types of filter equipment fields, the general noise distribution and the spectral characteristic of filter capacitor and reactor are obtained. The measurement results illustrated that the sound signal processing array technique based on beam forming algorithm is very useful for noise positioning and extraction in filter equipment field. The maximum noise source could be found and the accuracy of noise abatement project could be largely improved.