基于改进变分模态分解的谐波检测方法  

Harmonic detection method based on improved Variational Mode Decomposition

作　　者：冯益林 FENG Yilin(Shanghai Minhang Gas-Fired Power Generation Co.,Ltd.,Shanghai 200245,China)

机构地区：[1]上海闵行燃气发电有限公司,上海200245

出　　处：《智能计算机与应用》2024年第11期93-98,共6页Intelligent Computer and Applications

摘　　要：针对电网谐波信号多变复杂,现有检测算法精度不高的问题,提出基于改进的变分模态分解(VMD)和Hilbert变换(HT)结合的谐波检测方法。首先,用分量的平均瞬时频率法来确定VMD的分解模态个数K,采集包含谐波的混合信号。其次,对采样信号进行VMD检测和分解,得到一系列固有模态分量(IMFs),并从中提取出基波分量和高次谐波;再对固有模态分量进行Hilbert变换,得到原始信号频谱值的关系以及各分量的特征参数;最后与经验模态分解(EMD)结果进行比较,仿真结果表明该算法检测谐波的精度较高,实时性好,能够满足谐波信号的检测要求。In order to solve the problems of complex harmonics,and improve the existing shortcomings that the feature extraction of existing detection algorithms is difficult and the detection accuracy is low,a detection method based on improved Variational Mode Decomposition(VMD)and Hilbert Transform(HT)is proposed.Firstly,the average instantaneous frequency method of components is used to determine the number of decomposition modes K of VMD.In Simulink,the power network model is simulated to collect the mixed signals containing harmonics.Secondly,the sampled signals are detected and decomposed by VMD,and a series of Intrinsic Mode Functions(IMFs)is obtained,where the fundamental and higher harmonics are extracted.Then,the Hilbert Transform is applied to the IMFs to obtain the relationship between the spectral values of the original signals and the characteristic parameters of each component.Comparing to the results of Empirical Mode Decomposition(EMD),the simulation results show that the algorithm has a higher accuracy and better real-time performance.It can meet the requirements of harmonic detection in power grid.

关 键 词：谐波 平均瞬时频率 VMD HILBERT变换 

分 类 号：TP391[自动化与计算机技术—计算机应用技术] TM74[自动化与计算机技术—计算机科学与技术]