Method for Partition Reconfiguration and Mutual Aid of Power Grids Under Extreme Events Oriented to Critical Load Guarantee

To address the challenge of frequent extreme events causing power grid failures and traditional post-fault recovery modes struggling to meet the rigid demand for continuous power supply to critical loads, this paper proposes a partition-based two-layer optimization strategy. First, a partitioning index coupling active power flow with reactive voltage sensitivity is constructed, and the Fast Newman algorithm is applied to obtain partitions tailored to extreme events. Second, a two-layer optimization model is established: the upper layer performs network reconfiguration to minimize the total load curtailment, while the lower layer coordinates adjustable resources and power mutual aid between partitions. A simulation verification using the IEEE 39-bus system shows that the proposed method efficiently makes decisions during extreme events, achieving zero interruption for critical loads and reducing the curtailment of non-critical loads to 374.9 MW—a reduction of 54 percent compared to the traditional centralized dispatch model. The partitioning results also exhibit a high modularity of 0.6554 and a low boundary power flow factor of 0.1321, confirming the structural and functional advantages of the proposed approach. The method demonstrates good practical application value in enhancing grid resilience.