Power systems voltage emergency control approach using trajectory sensitivities

Very stressed power systems often lack ability to withstand certain disturbances, what might result in serious consequences. Therefore, the tools mitigating such a situation have a crucial significance. This paper presents a method for real-time stability assessment and emergency control of power systems based on the trajectory sensitivities. Out of the present conditions a nominal trajectory and its sensitivities is precalculated. If an incipient instability is detected, necessary stabilizing control measures are determined. A short review of trajectory sensitivities is included. A principal description of the method together with a theoretical foundation and examples with simulation results is provided.