Direct Detection of Instability Points Using an Augmented Formulation

This paper introduces an augmented formulation to directly compute instability points in power systems. The formulation is an extension of the direct \Point of Collapse" formulation for the computation of static system instabilities. The paper demonstrates the differences between purely static limits (based on power ow Jacobians) and steady-state dynamic instability points (based on eigenvalue determination). Steady-state dynamic instabilities often dominate system behavior. The paper discusses both kinds of dynamic instabilities: Hopf bifurcations and voltage collapse. When controlled devices such as AVR (Automatic Voltage Regulators) and SVC (Static VAR Compensators) components are added, Hopf bifurcations rather than voltage collapse often dominates system behavior. A technique to set controller gains in SVC devices in order to improve dynamic stability limits is described.