Methods for calculating oscillations in large power systems

The authors present algorithms to calculate the Hopf bifurcation related segment of the feasibility boundary for a realistically large power system model. The algorithms are used by calculating the Hopf-related segment of the feasibility boundary, for the well-recorded June 12, 1992 disturbance on the midwestern segment of the US interconnected power system for analyzing the resulting oscillations. The computational results confirm that this event was indeed related to a Hopf bifurcation. This proposed method clarified the operational perspectives of the low frequency power oscillation that occurred. It also demonstrated the value of the proposed computational approach in assessing the security of an operating point in an area of the parameter space.