  Direct methods can provide rapid screening of the dynamical security of large
numbers fault and contingency scenarios by avoiding extensive time simulation.
We introduce a computationally-efficient direct method based on optimization
that leverages efficient cutting plane techniques. The method considers both
unstable equilibrium points and the effects of additional relay tripping on
dynamical security\cite{01SH}. Similar to other direct methods, our approach
yields conservative results for dynamical security, however, the optimization
formulation potentially lends itself to the inclusion of additional constraints
to reduce this conservatism.

Systems and Control;Optimization and Control