Real-time preventive actions for the enhancement of voltage-degraded trajectories

This paper deals with the development of a nonlinear programming methodology for evaluating preventive actions to improve the dynamic security of power systems when poor voltage transients are detected. For the proposed power system modeling, voltage-degraded trajectories arise from both angle and voltage instability on the transient time scale. The rescheduling of the generation improves power system security by ensuring an acceptable voltage transient behavior and constraining the system to be stable. The algorithm is implemented and tested on an actual power system.