Research On Optimization Strategy Of Under Frequency Load Shedding In Complex Power System

Nowadays, the power system fault phenomenon is usually lack of power, and this can make the system frequency drop. If the system unit reserved spare capacity is insufficient to maintain the system frequency, the power gap value of system must be removed, so as to ensure the normal and stable the operation of the system. So, about the low frequency load shedding(under frequency load shedding, UFLS)plan of study is very important.In this paper, the first step is established the optimal tide lightening model with considering the load shedding cost. And it combines with the original dual interior point to solce the optimization results of cutting each load.On this basis, to join the effects of immobilized, envisioned by quick sort method to determine the system fault state set, for Jane little lightening device configuration at the same time, using the cluster analysis algorithm to the system fault state clustering analysis. Finally, combining the cost and the risk index of the frequency deviation, at the same time, put 0-1 integer programming into this will reduce the loads discretization processing. Using the original is applied to solve the dual interior point for each fault set under a set of feeder excision and the corresponding system fault conditions the optimal cutting load of each node through the Matlab software platform to realize the solution of the model, the numerical example results show that the model under the premise that ensures the stable movement of the system achieve the minimum cost.To analyze the frequency recovery system under this scheme, the final DIgSILENT simulation software is using in the IEEE 39 node model system.The frequency characteristic and the dynamic element model is established, and the traditional UFLS is compared to the load shedding strategy in this paper, and then it is verified the feasibility of the optimized load shedding strategy.