Thermal power units with fast cut back (FCB) function, which can continue to provide power to auxiliary equipment in power plants and supply power to the power outage area quickly after a blackout accident occurs, are excellent black start sources. The location strategy of FCB units can affect the restorability of the power system. Given this background, an optimal location model of FCB units considering system restorability is proposed. First, the power generation characteristics of the FCB unit and non-black start unit in the power system restoration process as well as the differences of power generation characteristics between these units are analyzed. Second, the optimal location model of FCB units is proposed to maximize power system restorability, and relevant constraints, such as power generation characteristics of units, the number of thermal units to be upgraded to FCB ones, and the power flows in the power system restoration process, are taken into account. The optimal location model of FCB units is constructed. The proposed model is reformulated as a mixed-integer linear programming one by employing linearization methods, and efficiently solved by commercial solvers. Finally, the IEEE 39-bus and 118-bus power systems are employed to verify the effectiveness of the proposed model. The simulation results show that the proposed location strategy of FCB units can effectively improve the restorability of power systems.

This work is supported by the National Natural Science Foundation of China (No. 51907043).