A Tri-Level Planning Approach to Resilient Expansion and Hardening of Coupled Power Distribution and Transportation Systems

Natural disasters which include major storms, floods, tornados, and hurricanes can seriously threaten the resilience of large and coupled infrastructures such as electric power distribution and transportation systems. This paper proposes a planning (i.e., investment + operation) method for enhancing the resilience of coupled power distribution and transportation systems. The proposed investment method includes capacity expansions of power lines, roads, and charging stations, and the hardening of roads and power lines. A tri-level problem is proposed and formulated to accommodate random natural disasters. The proposed model is solved by applying the Benders decomposition and the column-and-constraint generation (C&CG) algorithms. Benders decomposition will decompose the tri-level coupled problem into a single-level master problem and a bi-level subproblem. However, the latter with binary variables is not a convex problem and cannot be converted to the maximization problem. The C&CG algorithm is applied to solve the bi-level subproblem with binary variables. The proposed resilience enhancement algorithm is tested using a coupled power distribution and transportation system with 21 electric buses and 20 roads and numerical results are analyzed to validate the effectiveness of the proposed planning method.