Power Supply Restoration Optimization Considering Topology and Faults of the Upper-Level

The adjustment of the power grid operation is achieved by changing the network topology through switch state switching, thereby enabling the transfer of loads within the power grid. This provides a solution to effectively alleviate issues of transmission congestion and equipment overload that arise during peak load periods. The paper begins with an analysis of the typical structure of a 220kV/110kV transmission system, deriving active power balance equations for various typical topologies and generalizing them in the form of the linear matrix. Building upon this foundation, the paper considers scenarios where a 220kV substation experiences voltage loss during a fault, leading to a loss of power supply to the 110kV substation it serves. A power supply restoration optimization model is developed, taking into account power backflow, to restore power supply to the loads served by the 220kV substation through power backflow from the unaffected 110kV lines. The problem is formulated as a mixed integer linear programming problem and solved using CPLEX. Finally, the effectiveness of the proposed model is validated through optimization tests and analysis conducted on a real power grid.