Voltage flicker envelope detection method based on windowed interpolation and parsing mode decomposition

Abstract

The invention discloses a voltage flicker envelope detection method based on windowed interpolation and parsing mode decomposition. The method comprises the following steps: converting a grid voltagecurrent signal under test from an analog signal to a digital signal through an analog-digital converter to obtain sampled data of N-point length; performing windowing correction processing on the sampled data of N-point length to obtain a windowing-corrected discrete voltage signal y(n); performing spectral analysis on the discrete voltage signal y(n) by double-spectrum-line interpolation FFT (Fast Fourier Transform), and solving a corrected fundamental frequency and phase to obtain a grid voltage synchronizing signal; extracting a component v(n) of a voltage flicker envelope signal by a parsing mode decomposition method; and performing spectral analysis on the component v(n) of the voltage flicker envelope signal to obtain an amplitude correction function and a frequency correcting function of the voltage flicker envelope signal. The method has the advantages of accurate extraction, high detection accuracy and high interference resistance, and can be applied to real-time detection ofvoltage flicker.

Description

technical field [0001] The invention relates to the field of power systems, in particular to a voltage flicker envelope detection method based on windowing interpolation and analytical mode decomposition. Background technique [0002] The application of fluctuating loads leads to voltage fluctuations in the power system and flickering of lighting equipment, which seriously affects the daily life of industrial production and is an important cause of failure and failure of power supply and consumption equipment. Flicker is one of the important parameters of current power quality. Accurate measurement of voltage flicker can provide scientific basis for suppressing and eliminating the influence of voltage fluctuation and flicker, so as to provide early warning for power system to take measures. For the method of separating the voltage fluctuation signal, most of the existing detection algorithms use the square demodulation detection method based on the IEC. This method of obtai...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to provide a voltage flicker envelope detection method based on windowing interpolation and analytical mode decomposition to solve the problem of using square demodulation detection based on IEC to separate voltage fluctuation signals in the prior art However, the calculation accuracy is low. If the calculation accuracy needs to be improved, a correction step needs to be added to the algorithm to achieve it, which in turn leads to technical problems such as complex structure of the entire algorithm and slow calculation speed.

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