Cooperative Planning of Active Distribution System With Renewable Energy Sources and Energy Storage Systems

In this paper, a multi-objective, multi-level model is proposed for active distribution system expansion planning with high-penetration renewable energy sources (RESs) and energy storage systems (ESSs). To optimize the planning of RESs, ESSs, and distribution networks cooperatively, a three-level optimization method is adopted based on the leader-follower strategy of hierarchic optimizations. In this model, the upper level and the middle-level serve to model the planning problems from different perspectives of multi-stakeholders; the lower level serves to model the operation aspect of ESSs. The multi-level model enables us to integrate operation optimization into a planning model and achieve the collaborative optimization of them in different time-scales. The multi-scenario tools and K-means clustering are adopted to deal with the uncertainties and capture the time-variable nature of RESs and load demand. In order to balance the multiple objectives of costs reduction, reliability improvement, and RES penetration promotion, a modified Pareto-based particle swarm optimization is employed to solve the proposed optimization problem. Finally, results obtained by case studies are presented and discussed, where the availability and the effectiveness of the proposed planning model are verified.