Ever-increasing consumption of the electricity in the distribution networks encounters network planners with new challenges in terms of expansion requirements. Expanding substations is a technical concern considering various binding conditions. Emerging Battery Energy Storage Systems (BESSs) have the potential to defer substation expansion needs effectively. Although various applications of the BESSs are considered in the literature previously, application of the BESSs to defer substation expansion plans is not addressed adequately. In this context, this paper proposes a novel Multi-Objective Mixed Integer Linear Programming (MOMILP) for BESS operation in distribution networks to simultaneously substation expansion deferral and cost reduction. The proposed model is highly flexible with respect to the planner preferences, without convergence problems, and easily solvable using commercial solvers. The model determines charging and discharging scheduling of the active and reactive power of the BESSs optimally to achieve maximum substation expansion deferral without increasing operation costs. Higher degrees of the expansion deferral can be achieved at the expanse of the negligible cost increase. Furthermore, details of the whole BESS system including various parts and active/reactive power relations and limits are modeled accurately to better demonstrate real-life situations. Results of the simulations demonstrate accuracy and also functionality of the proposed method.
- Battery energy storage system
- Mixed integer linear programming
- Multi-objective optimization
- Optimal operation
- Substation expansion deferral