Method and device for measuring harmonic waves and inter-harmonic waves in power system

Abstract

The invention provides a method and a device for measuring harmonic waves and inter-harmonic waves in a power system. The method comprises the following steps of: a Gaussian window is added for the time domain of the sampled electric signal in the power system and fast discrete Fourier transform is performed; a signal spectrum is generated, a plurality of Gaussian radial basis functions are constructed according to the number of wave crests in the frequency spectrum; the signal frequency spectrum is processed, iterative training is carried out on the to-be-trained target function, so that theto-be-trained target function approaches the processed signal frequency spectrum, and the harmonic signal and the inter-harmonic signal are respectively measured according to the parameters corresponding to the trained target function. Thus, according to the embodiment of the invention, a series of Gaussian radial basis functions are constructed according to the number of wave crests of the frequency spectrum after fast Fourier transform, the frequency spectrum generating the inter-spectral interference is approximated by utilizing linear superposition of the Gaussian radial basis functions, harmonic and inter-harmonic components generating the main lobe interference in the electric signal can be accurately distinguished, and the measurement precision is relatively high.

Description

technical field [0001] The present application relates to the technical field of power quality, in particular to a method and device for measuring harmonics and interharmonics in a power system. Background technique [0002] Since many load devices widely used in power systems are fluctuating, the problem of interharmonic pollution caused by fluctuating loads is becoming more and more serious. Inter-harmonics will amplify voltage flicker and audio interference, affect transmission images and increase noise, shorten the service life of related equipment in the power system, increase energy consumption of power lines, and seriously affect power quality. Detection and analysis are of great significance. [0003] The harmonic analysis of the power system usually adopts the fast Fourier transform method, but because the inter-harmonic is not an integer multiple of the power frequency, spectrum leakage usually occurs when measuring signals containing inter-harmonic. In order to ...

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Problems solved by technology

[0005] This application provides a method and device for measuring harmonics and interharmonics in a power system, which can be used to solve the main lobe interference that is prone to occur in the prior art, making it difficult to distinguish the harmonics and interharmonics of electrical signals in the power system, and further Technical issues that make accurate measurements of harmonics and interharmonics difficult

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