Tri-level allocation method of distributed energy storage system based on sharing strategy in active distribution networks

Abstract

Abstract More and more distributed energy storage (DES) are integrating into active distribution networks (ADNs), which has a positive effect on both distribution companies (DISCOs) and consumers. In order to achieve peak-load shifting and reduce the electricity purchasing costs, from the perspective of an independent energy storage operator, a tri-level allocation model of DES in an ADN is built based on a sharing strategy. The tri-level model is a multi-objective optimization problem: the upper-stage model optimizes the siting and sizing of DES with the objective of minimizing the annual costs of investment; the middle-stage model realizes an optimal distribution of energy storage capacity to the DISCO and consumers with the objective including the operating costs of the DISCO and consumers, and peak-valley differences; in the lower-stage model, the optimal operation scheme of DES can be acquired with the objective of minimizing the operating costs of the DISCO and consumers. A method combining adaptive genetic algorithm (GA) and second-order cone programming (SOCP) is adopted to solve the model. Simulation results on the IEEE 33 bus system show that the tri-level allocation method can effectively reduce the RES investment costs, reduce the peak-valley differences, and improve the revenues of both the DISCO and consumers.