摘要
变分模态分解(VMD)已在谐波检测领域得到应用,但人为设定分解参数K,导致误差较大。为提升VMD在间谐波检测中的准确性,首先,采用施密特正交化理论对VMD预分解得到的各分量进行正交化处理,以避免模态混叠。然后求得不同K值对应的残差能量,利用残差能量值最小化法优化参数K,进而提取间谐波信号。最后采用对称差分能量算子,获得间谐波信号幅值与频率等特征信息。仿真实验表明:所提出的方法能有效优化参数K,降低VMD分解误差。同经验模态分解(EMD)、集合经验模态分解(EEMD)以及近年新提出的同步挤压小波变换(SST)相比,参数优化变分模态分解在间谐波检测上效果显著提升,具有更高的检测精度。
Variational mode decomposition(VMD)has been applied in the field of harmonic detection,but the error is large when the decomposition parameter K is artificially set.In order to improve the accuracy of VMD in inter-harmonic detection,first,Schmidt orthogonalization theory is used to orthogonalize the components obtained from VMD pre-decomposition in order to avoid modal aliasing.Then the residual energy corresponding to different K values is obtained,and the residual energy value minimization method is used to optimize the parameter K,and then extract the inter-harmonic signal.Finally,a symmetrical difference energy operator is used to obtain characteristic information such as the amplitude and frequency of the inter-harmonic signal.Simulation results show that the proposed method can effectively optimize the parameter K and reduce the VMD decomposition error.Compared with empirical mode decomposition(EMD),ensemble empirical mode decomposition(EEMD)and synchrosqueezing wavelet transform(SST)proposed in recent years,parameter optimized variational mode decomposition is more effective in inter-harmonic detection and has higher detection accuracy.
作者
郑晓娇
王斌
李卜娟
喻敏
ZHENG Xiaojiao;WANG Bin;LI Bujuan;YU Min(School of Information Science and Engineering,Wuhan University of Science and Technology,Wuhan 430081,China;School of Science,Wuhan University of Science and Technology,Wuhan 430065,China)
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2022年第11期71-80,共10页
Power System Protection and Control
基金
国家自然科学基金项目资助(51877161)
湖北省教育厅科研计划指导项目资助(B2018006)。
关键词
间谐波
变分模态分解
施密特正交化
残差能量
对称差分能量算子
inter-harmonic
variational mode decomposition
Schmidt orthogonality
residual energy
symmetric difference energy operator
