Estimation of modal parameters of low frequency oscillations in power system using Hankels total least square method

摘要

This paper proposes a Hankels total least square (HTLS) based method for determining the modal parameters of the low frequency oscillations present in the power system. HTLS being a parametric method requires an estimate of the model order of the signal for its successful performance. In the proposed method, the model order estimate is obtained based on the number of peaks present in the FFT plot of the signal. The performance of the proposed method is compared with that of a Fourier based method and Modified Prony based method at different levels of signal to noise ratios and PMU reporting rates using real as well as synthetic signals. It is observed that, in comparison to the above mentioned methods, the proposed method is least affected by the noise contamination and low PMU reporting rates making it a better choice for modal estimation of low frequency oscillations.