An Real-Time Emergency Control Method Based On Unbalanced Transient Energy Function

Abstract

Abstract In this paper, an emergency control strategy by combining generator tripping and load shedding is presented. Firstly, the unbalanced transient energy function of power system is defined, and its key features are analysed. Then, by combining the unbalanced power characteristics for power system in steady state operation condition, the method for calculating the control quantities of generator tripping and load shedding is proposed. Furthermore, a realtime closed-loop emergency control strategy is proposed. Since the proposed method by only using measurement data is based on the essential of transient instability, the accurate control quantities can be obtained. Compared with single generator tripping control, the low frequency and low voltage problem of system can be improved effectively with the combined emergency control strategy. Simulation results of New England 39-bus system validate the effectiveness of the proposed control strategy.