Sensitivity-based hybrid approach for assessment of stability-constrained generation limit

Based on an improved hybrid method for transient stability assessment, a new sensitivity-based approach for stability-constrained generation limit assessment is proposed. The variation characteristic of minimum kinetic energy (KE) in post-fault duration against generation of severely disturbed generators is studied. The study shows that the active minimum KE is much more sensitive to a generation change of severely disturbed generators than inactive KE is, and the sensitivity factor of minimum KE could be used to predict generation limit. With this knowledge, a method for evaluating sensitivity factors of minimum KE in conjunction with trajectory and trajectory-sensitivity simulation is presented. It has the advantage that the approach is usable for systems represented by complex models. The effectiveness of the sensitivity-based hybrid approach is shown through case studies on the ten-generator New England test system.