Unbalanced Distribution System Expansion and Energy Storage Planning Under Wildfire Risk

Reducing the risks of wildfire ignition has become a major concern for many electric utilities. In recent years, they have relied on Public Safety Power Shutoff (PSPS) programs to de-energize select power lines to prevent wildfire risks. A cost-effective solution for the power distribution system expansion planning in regions with increased wildfire risk could be achieved by jointly combining new distribution lines and energy storage systems (ESSs) while taking into account the overhead distribution lines availability given the increasing number of PSPS events. This paper proposes a two-stage stochastic optimization approach for the expansion planning of a power distribution system under wildfire risk with a compliance check on unbalanced power flow and system operation limits. The resulting model is a mixed-integer linear programming (MILP) optimization problem. The proposed model is validated on a modified version of the IEEE 13-node system and the IEEE 123-node system. Simulation experiments and sensitivity analysis are performed to validate the effectiveness of the proposed formulation using different High Fire-Threat District (HFTD) Tier Zones based on real-world data from electric utilities in California.