Fast identification of oscillatory stability margin and damping margin using continuation of invariant subspaces with sensitivity

An improved continuation of invariant subspaces with sensitivity is proposed for fast identification of oscillatory stability margin and damping margin in power systems. Spectrum transformation based methods are introduced to efficiently calculate the critical eigenvalues of interest for initialization. The predictor-corrector method is applied to trace the movement of eigenvalues as power system parameter changes. Eigenvalue sensitivity is a by-product of the algorithm. From the sensitivity information, a step size control method is introduced to fast identify both the oscillatory stability margin and damping margin. The simulation results on New England 39-bus system are demonstrated in details.