A New Method for Analyzing Oscillation Eigenvalues of Uncertain System Utilizing 2nd Order Perturbation

This paper proposes a method to analyze the low frequency oscillation (LFO) eigenvalues of uncertain system based on second-order perturbation. Firstly, the uncertain parameters are described by the interval models. Then, with second-order perturbation and interval extension, the upper and lower bounds of eigenvalues are calculated. Finally, the influence of different parameters to eigenvalues is analyzed quantitatively. Testing results show that the algorithm can track the oscillation modes on-line more accurately compared to first-order perturbation and it can increase the fundamental understanding of inter-area oscillations and is helpful to make correct control strategies to restrain the oscillation.