Unit-Restarting Strategy For Eastern Liaoning Power System After Blackout

With the scale of the interconnected power system across the region increasing larger, the operating performance gets better, but it also causes some new problems.Local system failure may lead to large-scale blackout and even collapse of the entire power system. After blackout, the restarting of generators is the basis of other restoration procedures. The restoration time of the power system, even the success of the restoration procedure, is related to the starting sequence of generators.Regional black start experiments have been conducted in recent years. However, the establishment of the unit restart plan relies on the manual selection based on experience.For large scale power systems, automatic algorithms are needed to decide the unit restoration plan, which not only meets the requirements of safety regulations but also accelerates the restoration process. So our study is of great significance. Due to the complexity of Liaoning Grid, the regional restoration method is employed. The regional power system in eastern Liaoning power system is studied in this paper.In this study, the procedure of unit-restarting is studied, and a discrete unit-restarting optimization method based on a multi-objective evolutionary algorithm is established.The topological graph is acquired according to the primary system diagram of Liaoning power system. The feasibility of taking Huanren hydraulic power plant as the black start unit is proved. The optimization objectives are established considering the power generation capacity and the restoration path distance. Manual selection of restoration paths is updated by the shortest path algorithm which automatically calculates the best path combination for the dispatchers. The non-dominated sorting genetic algorithm(NSGA-II) is employed to solve the multi-objective optimization problem. Based on the obtained Pareto-optimal set, the comprehensive assessment method based on the coefficient of variation method is applied to decide the best scheme. Aiming at the regional system in eastern Liaoning power system, the relative strategy is acquired using the method proposed above, which provides convenient guidance to dispatchers.