Model-based synchrophasor estimation by exploiting the eigensystem realization approach

• Published in: Electric power systems research Vol. 182; p. 106249
• Main Authors: Zamora-Mendez, Alejandro, Zelaya-A., Francisco, de la O Serna, José Antonio, Chow, Joe H., Arrieta Paternina, Mario R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2020; Elsevier Science Ltd
• Subjects: Algorithms; Amplitudes; Eigensystem realization; Eigenvalues; Electric power lines; Estimates; Estimating techniques; Fault diagnosis; Fourier transforms; Frequency estimates; Measurement; Phasor estimation algorithm; Phasor measurement unit; Phasors; Prony's method; Synchrophasors; Frequency estimates; Phasor estimation algorithm; Synchrophasors; Phasor measurement unit; Eigensystem realization
• ISSN: 0378-7796; 1873-2046
• DOI: 10.1016/j.epsr.2020.106249

•The ER-based estimation method improves the frequency computation and its tracking since it is a frequency adaptive method, reducing the total vector error (TVE), even in the presence of dynamic compliances reported in the IEEE Synchrophasor Std. C37.118.•The proposal focuses on measuring synchrophasors and increasing their accuracy due to it is a model based phasor estimator that exploits the system identification theory by means of the eigensystem realization approach; specifically, the ER-based phasor estimator deals with different dynamic compliances from theoretical and real signals, being able to extract the rate of change of amplitude (ROCOA).•This paper adopts a signal model-based phasor regarding complex exponential signals, which enables that transient and harmonics can be accurately and timely processed in order to capture the phasor dynamics.•The implementation of the ER approach is computationally efficient, providing phasor estimates in shorttime for power system monitoring and protecting. This paper proposes an eigensystem realization (ER) approach to accurately provide synchrophasor estimates. The proposal improves the frequency computation and its tracking since the ER-based estimator works as a frequency adaptive method, reducing the total vector error (TVE) in the presence of dynamic compliances reported in the IEEE Synchrophasor Std. C37.118. Phasor estimates such as amplitude, phase, frequency and the rate of change of amplitude (ROCOA) can be provided in one-cycle. The new ER-based phasor estimator is evaluated under steady-state, dynamic and noisy conditions using both theoretical and actual signals stemming from a commercial PMU and a Digital Fault Recorder (DFR). Comparisons are established with the well known Discrete Fourier Transform (DFT), Prony method and the Interpolated DFT (IpDFT). Finally, the results exhibit that the proposed approach attains reliable estimates, even though under polluted conditions by high harmonic content, being able to track the changes in amplitude, phase, frequency, with enough precision. Thus, the eigensystem realization-based method becomes a class P phasor measurement algorithm.