Robust RLS Methods for Online Estimation of Power System Electromechanical Modes

Spectral estimation of low-frequency oscillations in the Nordic grid using ambient synchrophasor data under the presence of forced oscillations

“…Adaptive tuning of autoregressive models by adaptive filtering techniques enables continuous modes tracking. This technique is introduced in [8] and further improved in [9]. A relatively new method for output-only mode identification, refereed to as Frequency Domain Decomposition (FDD), has also been applied for mode estimation in power systems [10].…”

Comparative review of methods for stability monitoring in electrical power systems and vibrating structures

“…The most used recursive methods are adaptive filter techniques of which least squares (LS) algorithms are the ones that have been applied to power systems [9], [10]. LS algorithms estimate a model for a set of data by assuming a functional form of the input probability density function and minimizing a penalty or cost function which is the sum of the square of the differences between the observed values and the ones obtained from the model.…”

“…Additionally, a forgetting factor, , which reduces the influence of large prediction errors is used to weight the error cost function [9]. The reason for including a forgetting factor is to make the filter less sensitive to small departures from the assumed functional form of the input probability distribution.…”

“…These described techniques are generally well known from system identification [2]. The algorithms are used to estimate autoregressive (AR) model paameters in [9] and [10]. The structure of these models is introduced in the following sub-section including the procedure of obtaining the system mode frequencies and damping values.…”

Parameter Estimation Method of Low-Frequency Oscillating Signals Using Discrete Fourier Transforms

“…Prony based estimation algorithms [10][11][12][13][14][15][16][17][18][19][20][21][22] have been developed and applied to this area. In practice, the Prony based estimation algorithms have been widely applied to the analysis of the dynamics in power systems.…”