Online monitoring of inter-area oscillations and damping of power systems employing prony analysis

Power system oscillations can be occurred due to several reasons including the weak tie lines and heavy load demand. Usually, the controllers in the power system damp out most of the unwanted oscillations. However, the unidentified and undamped oscillations may persist which can collapse the system. Some power system blackout incidents occur due to the unidentified low-frequency oscillations. Consequently, proper identification of the low-frequency oscillation is considered as one of the crucial tasks by the power system operators for secure operation. This paper presents Prony analysis (PA), a signal processing-based technique for the detection of the low-frequency oscillation and damping at each moving windowed ringdown signal. The comparison of the obtained results with the fast Fourier transform and Welch power spectral density estimation-based techniques confirms the superiority of the proposed PA technique. In addition, this research designs and implements a real-time low frequency and damping monitoring algorithm for the two-area and four machines power system in MATLAB/SIMULINK platform. The retrieved results of the proposed technique show satisfactory performance in identifying and tracking the inter-area oscillation.