A control method and device for avoiding large-scale wind farm resonance

Abstract

Disclosed is a control method for avoiding large-wind-field resonance. The control method includes the steps of 1), performing data measurement acquisition and processing analysis by taking an exit of a wind power field as a measurement point, acquiring voltage and current data, sequentially performing high-pass filtering (HPF) and discrete Fourier decomposition (DFT) signal processing, calculating harmonic impedance of a wind power field system by the aid of a thevenin equivalent theorem, and performing analysis on calculated harmonic impedance results to acquire resonant frequency; 2), performing logic calculation on cutting capacity of a parallel capacitor, and judging whether the resistance value of an electric-field connecting point is located within the range of + / -30% of two intermediate impedance values or not by the aid of sequences of switching in and switching on under certain capacitor capacity till requirements are met; 3), the transistors controlling capacitor banks to be merged into a power grid for operation. The invention further provides a control device for avoiding large-wind-field resonance. By the control method and device, higher harmonic resonance can be effectively avoided, and potential safety hazards can be effectively removed.

Description

technical field [0001] The invention relates to the technical field of wind farms, in particular to a control method and a control device for avoiding resonance of wind farms. Background technique [0002] The rapid development of power electronic technology has affected the wide application of various power electronic devices in power systems, industries, transportation and households, resulting in increasingly prominent harmonic problems and increasingly serious harm caused by harmonics. [0003] For a long time, my country's wind power industry has followed the route of "large-scale, highly concentrated development, and long-distance, high-voltage transmission" to develop large-scale wind farms and integrate them into large power grids. Wind power grid connection will cause power quality problems. Because the harmonics have a serious impact and harm on the power grid, the harmonic problem of wind turbines connected to the power grid has become one of the power quality pro...

AI Technical Summary

Problems solved by technology

[0006] In order to overcome the problems of unavoidable high-order harmonic resonance and potential safety hazards in existing wind farms, the present invention provides a control method for avoiding large-scale wind farm resonance that effectively avoids high-order harmonic resonance and eliminates potential safety hazards and its device

Images