Distribution Systems Hardening Against Natural Disasters

Distribution systems are often crippled by catastrophic damage caused by a natural disaster. Well-designed hardening can significantly improve the performance of postdisaster restoration operations. Such performance is quantified by a resilience measure associated with the operability trajectory. The distribution system hardening problem can be formulated as a two-stage stochastic problem, where the inner operational problem addresses the proper scheduling of postdisaster repairs and the outer problem the judicious selection of components to harden. We propose a deterministic single crew approximation with two solution methods, a mixed integer linear programming (MILP) formulation and a heuristic approach. We provide computational evidence on various IEEE test feeders, which illustrates that the heuristic approach provides near-optimal hardening solutions efficiently.