Hierarchical Optimal Planning of Battery Energy Storage Systems in Radial Distribution Networks

In this paper, an optimal planning model of battery energy storage systems (BESS) in radial distribution networks is proposed to regulate bus voltage and reduce energy cost. The optimal number, locations and capacity for BESS is obtained by a hierarchical optimal planning model. The model firstly determines the BESS number. Then the most effective locations can be selected based on voltage sensitivity analysis. Given the number and location, the BESS capacity can be determined by a constrained mixed-integer nonlinear programming problem solved by natural aggregation algorithm (NAA). The final configuration of BESS is determined by voltage regulation constrained minimizing the total life cycle cost, which includes the system operation cost, investment cost, residual value of BESS, and, etc. A case study conducted on a modified IEEE 15-bus distribution system shows the performance and outcome of the optimal planning model.