Power distribution system improvement planning under hurricanes based on a new resilience index

Natural disasters such as hurricanes damage power distribution systems by low probability- high impact events. Other infrastructures such as water networks will be disrupted due to their dependency on the power network. In this situation, a city or region experiences critical conditions. In this paper, a new resilience index based on social welfare concept is presented to decrease unserved loads, restore the distribution system rapidly and decrease the dependency of water network operation to power network failures. The new resilience index is optimized with effective strategies including: upgrading distribution poles, DG placement with different capacities and distribution system automation. The problem is formulated as a stochastic two-stage optimization. The first-stage decisions are the number of each resilience improvement strategy limited to a predetermined budget. Genetic algorithm is applied to solve the first stage. The objective of the second stage is maximizing the social welfare which is solved by an innovative approach. Numerical simulations are performed on the IEEE 33-bus radial distribution system and designed water network related to it. The results demonstrate the effectiveness of the proposed method.