A Line Hardening Planning Method for Power System Considering Coordination of Transmission and Distribution Systems

To enhance the resilience of power system against typhoon disasters, this paper proposes a bi-level line hardening planning method considering coordination of transmission and distribution systems (T&D). The spatiotemporal evolution of typhoons is modeled using the Batts wind field and empirical path model. A fault uncertainty set is constructed based on line vulnerability and information entropy. The upper level optimizes line hardening decisions to minimize total investment and operational costs, while the lower level simulates system response under disaster scenarios, incorporating coordinated T&D dispatch and distributed generation support. Case studies on a modified IEEE 39-bus transmission system integrated with three IEEE 33bus distribution networks validate the effectiveness of the proposed approach.