Maximum likelihood frequency estimation in smart grid applications

Vincent V. Choqueuse (1) , El Houssin El Bouchikhi (1, 2) , Mohamed Benbouzid (1)

1 LBMS - Laboratoire brestois de mécanique et des systèmes
2 LABISEN-ESE - Energie et Systèmes Electromécaniques

This paper focuses on the estimation of the fundamental frequency in balanced three-phase power systems. Specifically, we propose a Maximum Likelihood Estimator (MLE) that exploits the multidimensional nature of electrical signals. For perfectly sinusoidal signals, we show that the MLE can be expressed according to the periodogram of the instantaneous positive component. For harmonic signals, we demonstrate that the MLE can be approximated by a cumulated periodogram of the zero, positive and negative sequence components. As compared to single-phase estimators, statistical analysis and simulation results prove that the proposed estimator decreases the Mean Square Error by a factor of three, whatever the Signal to Noise Ratio (SNR) or data length. Furthermore, simulations with experimental data show that the proposed technique outperforms classical spectral estimators such as MUSIC.

Mots clés: Index Terms—Frequency Estimation; Power System; Smart Grid; Maximum Likelihood Estimator; Cramér -Rao Bounds

Domaines: Traitement du signal et de l'image [eess.SP]

Vincent V. Choqueuse, El Houssin El Bouchikhi, Mohamed Benbouzid. Maximum likelihood frequency estimation in smart grid applications. ISIE 2015, Jun 2015, Buzios, Brazil. ⟨10.1109/ISIE.2015.7281667⟩. ⟨hal-01212112⟩