Abstract:

Integration of wind farms into power systems may increase the risk of power system blackouts due to the uncertain nature of their output power. In the meantime, wind turbines have relatively short starting time when compared to non-black-start (NBS) generating units. For this reason, wind farms need to participate in power system restoration after blackouts. The decision of restoring a wind farm depends on its output power and the characteristics of the power system. The power system restoration should be accomplished as soon as possible. For complete power system restoration, three stages must be completed: generation restoration, transmission system restoration, and load pick up. To achieve a faster restoration process, an optimal schedule for the black-start units to crank the NBS units is required with optimal transmission path selection. During the restoration process, to maintain the stability of the system and satisfy the system's operational constraints, an optimal load pick up sequence is required. In this paper, the firefly optimization algorithm is used to find the optimal final sequence of NBS unit restoration, the optimal transmission paths, and the optimal load pick up sequence with and without integration of wind farms in the system. The objective is to minimize the overall restoration time and the unserved load, which maximizes the energy capability and improves the sustainability of the system. The proposed algorithm is applied successfully to the IEEE 39-bus system.

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