Three-side coordinated dispatching method for intelligent distribution network considering dynamic capacity division of shared energy storage system

Abstract

Shared Energy Storage Systems (SESSs) are increasingly being integrated into Intelligent Distribution Networks (IDNs). IDNs are transitioning from traditional electricity distributors to multi-type energy supply platforms with SESSs and multi-type microgrids (MGs). Compared to traditional distribution networks, IDNs need to meet the integration and cooperation requirements of the flexible resources from both external agents and internal source-network-load-storage side. However, these external and internal factors have complex coupling relationships. Fully maximizing the potential benefits of SESSs for improving IDNs, SESSs, and MGs remains a challenge. This paper proposes a three-side coordinated dispatching method for IDNs. Its characteristic is a business model for SESS considering virtual MG was proposed. SESS capacity could be utilized fully, improving the economic benefits of all parties including SESS operator. First, the autonomous operation mechanism of the SESS was provided, and a dynamic capacity division model was established. The remaining SESS capacity was then used for IDN optimal dispatching in the form of a virtual MG. Second, an optimal control model of an integrated energy MG was established, and a new MG structure that allows for a multi-node grid connection was designed. Subsequently, this study developed an information exchange method between multiple agents and a solution strategy to solve the IDN-MG-SESS three-side coordinated dispatching model. Finally, an improved IEEE 33-bus system with two MGs and a SESS was analysed. The SESS dynamic capacity division method, when compared to configuring the SESS capacity according to the installed capacity ratio of distributed generation, increased the daily economic income of the SESS by 26.19 %.