一种综合分析算法在低频振荡参数估计中的应用(英文)

A Hybrid Method for Estimation of Low Frequency Oscillation Parameters

为消除实测信号中噪声的影响,更好地揭示电力系统低频振荡的时变和非线性特征,提出了基于广义数学形态学非线性滤波和Hilbert-Huang变换(HHT)的低频振荡综合分析算法。首先分析了信号中各种噪声对HHT精度的影响。在形态学滤波原理的基础上,建立了广义形态学滤波器,并利用它对来自广域测量系统(WAMS)中低频振荡信号进行滤波去噪,然后将滤波后的信号经过HHT分析处理后,再通过相应的瞬时参数计算方法,求解出低频振荡信号的瞬时参数。仿真结果证明该算法不仅能有效地消除信号中的混合噪声,而且能够计算出低频振荡主导模态的瞬时参数,更好地分析低频振荡的瞬时特性。通过对来自WAMS的实际信号进行分析,证明了该方法的有效性。

In order to investigate the time-varying non-linear characteristics of low frequency oscillations（LFOs）,a hybrid technique based on generalized mathematical morphological（MM）filter and Hilbert-Huang transform（HHT）is presented.First of all,the influences of different kinds of noises on HHT are analyzed.And then the generalized MM filter is built based on its principle and ability to filter the mixed noise.The data from wide are ameasurement system（WAMS） are utilized as the input of generalized MM filter,which can eliminate mixed noiserapidly and effectively.The filtered signals are analyzed by HHT,and then the instantaneous parameters of the dominant oscillation are calculated.Simulation results of the testing signal and practical signal from WAMS validate the presented hybrid estimation method.