Security Constrained Unit Commitment Problem with Energy Storage System and Demand Flexibility Constraints

Unit commitment is a challenging optimization problem that is critical in power system operational planning. Considering N − 1 security criteria, along with transmission lines and operational limitations, leads to a generic security constrained unit commitment (SCUC) problem. Traditional SCUC formulations for large power systems using injection sensitivity factors are computationally intensive and thus are restrictive. This work proposes an efficient framework for SCUC with energy storage systems (ESSs) and flexible loads, using the line outage distribution factors. Case studies analyze the impact of ESSs and flexible loads on the SCUC results and form a useful guideline for research community. Presented case studies accentuate the individual and combined impact of ESS and flexible demands on the total operation cost, unit commitment status, and power schedules of thermal units of a modified 118-bus system at two different loading levels.