Eigenvalue-based wide area stability monitoring of power systems

Background oscillations are utilized for the real-time stability evaluation of electric power systems. After identifying the parameters of the low-order discrete-time model for the target system from the background oscillations measured at two different locations, the stability of the target system has been evaluated through the eigenvalues of the identified discrete-time model. Real-time simulations have been performed for a longitudinal four-machine infinite-bus system on the Analog Power System Simulator at the Research Laboratory of the Kyushu Electric Power Co. to demonstrate the efficiency of the proposed scheme. The accuracy of the proposed scheme for the real-time stability evaluation has also been clarified through the comparisons with the alternative stability evaluation in the time domain, and also in the frequency domain.