基于改进小波变换法的风电场谐波检测

为了提高风电并网电力系统谐波检测的快速性与准确性,提出一种改进小波变换的谐波检测方法。首先,把风电并网系统电压信号的频域空间分割成低频区段与高频区段,针对低频区段信号采用小波多尺度算法分解,针对高频区段信号采用小波包进行分解,得到信号中的基波和各次谐波分量;然后,通过有效地提取出特定频率段的谐波分量进行重构来检测风电并网电力系统谐波;最后,利用MATLAB进行了仿真实验。实验结果表明:该方法能快速有效检测出谐波分量,提高了谐波检测准确度和快速性。

Wind Farm Harmonic Detection Based on Improved Wavelet Transform

In order to improve the fastness and accuracy of harmonic detection in wind power grid-connected power system,a harmonic detection method based on wavelet transform is proposed.Firstly,the frequency domain of the voltage signal of the wind power grid-connected system is divided into low-frequency section and high-frequency section.The low-frequency section signal is decomposed by wavelet multi-scale algorithm,and the high-frequency section signal is decomposed by wavelet packet to obtain the fundamental wave and each harmonic component of the signal;then,the harmonic components of the specific frequency segment are effectively extracted for reconstruction to detect the harmonics of the wind power grid-connected power system;finally,the simulation experiment is carried out by using MATLAB.The experimental results show that the method can detect harmonic components quickly and effectively,and improve the accuracy and rapidity of harmonic detection.