Design of a Two-Stage Emergency Control Strategy with Energy Storage and Transmission Line Thermal Dynamics for Large-Scale New Energy Base Power Export

In the context of large-scale integration and long-distance power export of new energy bases, the strong volatility and uncertainty of wind and solar generation intensify the operational risks of the power grid under extreme contingencies. To address the increasing requirements for regulation capability and resilience in power export systems of large-scale new energy bases, this paper proposes a two-stage emergency control strategy that considers the dynamic thermal characteristics of transmission lines. First, a power flow-weighted electrical betweenness index based on complex network theory is used to identify critical nodes and transmission lines with high power flow concentration. A two-stage emergency control model is then established: the pre-contingency stage enhances system preventive capability through optimizing generation scheduling, storage deployment, and load-shedding point selection, while the post-contingency stage dynamically adjusts regulation resources by incorporating wind power uncertainties and fault scenarios. Case studies on the IEEE 30-bus system demonstrate that the proposed strategy can effectively exploit line thermal inertia, improving the fault tolerance and recovery capability of the power export system of new energy bases, achieving both enhanced security and economic performance.