Analysis of Oscillations with Eigenanalysis and Prony Techniques

This paper demonstrates the complementary usefulness of small signal (eigen) analysis and Prony techniques for analysis (and resolution) of lightly damped oscillations in a practical power system. The techniques are applied to a) derivation of mode shapes associated with lightly damped oscillation modes, b) tuning of power system stabilizers (PSSs), and c) application of power oscillation damping (POD) controls to existing SVCs. Eigenvalue and eigenvector calculations provide a firm theoretical justification. Associated sensitivities provide guidance and rank the most effective locations for damping of oscillations. They also help in designing and tuning stabilizing controls. Prony analyses, on the other hand, are rooted on time simulations; simulations that are familiar to most analysts. The paper illustrates the significant synergies between Prony analyses and eigen analyses techniques in the study of oscillatory dynamics.