Detection method of voltage flicker parameters based on symmetrical mode decomposition of extreme points

Abstract

The invention relates to a voltage flicker parameter detection method based on extreme point symmetry mode decomposition. Based on the extreme symmetry mode decomposition theory and algorithm, a voltage flicker parameter detection step based on ESMD extreme point symmetry mode decomposition is given. Firstly, a voltage flicker signal is decomposed into single-frequency amplitude-modulated waves bythe ESMD method, and then the instantaneous amplitude and instantaneous frequency information of each single-frequency amplitude-modulated wave is obtained by the direct interpolation DI method. Theover-fitting and under-fitting of an envelope of the EMD method is overcome, and the modal aliasing phenomenon of the EMD method can be effectively avoided in the detection without adding noise; the defect that the detection result of the EEMD method strongly depends on the selected noise is overcome. The voltage flicker parameter detection method has strong self-decomposing ability in the detection of voltage flicker parameters, high detection precision, good real-time performance, less false mode, small end-end distortion of an amplitude-frequency curve, and small fluctuation.

Description

technical field [0001] The invention relates to a detection technology, in particular to a voltage flicker parameter detection method based on extreme point symmetric mode decomposition. Background technique [0002] In the context of the Energy Internet, the energy input forms of the power grid are diversified, and the disturbance problems faced by the power quality of the power grid are more complicated; among them, various high-power, impact, and nonlinear loads become the main sources that affect power quality; and based on micro-processing The precision electronic device of the device has higher and higher requirements for power quality; therefore, the society has higher and higher requirements for power quality, and the importance of power quality monitoring and management has become increasingly prominent. Accurate and timely detection of power quality is the premise of its governance. Among them, flicker is one of the most important forms of power quality disturbanc...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims at the problem of low accuracy of the existing power system fluctuation signal detection method, and proposes a voltage flicker parameter detection method based on extreme point symmetric mode decomposition. Firstly, the pole symmetric mode decomposition is performed on the signal to obtain a A series of intrinsic mode functions IMF with different characteristic scales, and then directly interpolate the IMF components to obtain the instantaneous amplitude and instantaneous frequency information of each harmonic

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