结合经验模态分解的信号能量法及其在低频振荡研究中的应用  

Signal Energy Method Based on EMD and Its Application to Research of Low Frequency Oscillations

作　　者：穆钢[1] 史坤鹏[1] 安军[1] 黎平[1] 严干贵[1] 

机构地区：[1]东北电力大学电气工程学院,吉林省吉林市132012

出　　处：《中国电机工程学报》2008年第19期36-41,共6页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50577004)~~

摘　　要：结合经验模态分解(empiricalmodedecomposition,EMD)算法和信号能量法,提出一种处理非平稳信号的改进方法——基于EMD的信号能量法,并将其应用于电力系统低频振荡阻尼特性研究中。该方法将信号能量作为误差判据引进EMD环节,克服了EMD过程难以消除虚假成分的弱点;同时,借助EMD处理非平稳的振荡信号,扩展了信号能量法应用范围。通过与普罗尼(Prony)算法、特征根分析进行比较,相量测量单元(phasormeasurementunit,PMU)设备量测轨迹和PSASP软件仿真曲线的算例分析证明,此方法能有效提取非轴对称振荡信号主导模式,且具有很好的复合模式分离能力。Signal energy method combined with empirical mode decomposition （EMD） was proposed, and applied to deal with non-stationary response to analyze the damping property of low frequency oscillations. An energy-error criterion was introduced to avoid the influence of false component in the process of EMD, and by means of the proposed method, the applied scene of signal energy method can be expanded. By comparison of proposed method with Prony algorithm and eigenvalue-analysis, case studies on measured phase-angle trajectories by phasor measurement unit （PMU） and the curves simulated by PSASP show that the proposed method has good performance to identify the dominant mode of off-axis- symmetrical signal, and the better ability of separating complex mode.

关 键 词：非平稳信号 经验模态分解 信号能量 低频振荡 阻尼特性 

分 类 号：TM76[电气工程—电力系统及自动化]