An Optimal Economic Dispatch Method for Enhancing the Operational Flexibility of Active Distribution Network with Distributed Energy Storage

With the high penetration of renewable energy sources (RES), the traditional distribution network has evolved into an active distribution network (ADN) which can effectively monitor and optimize the scheduling of RES. However, the operational flexibility of ADN is significantly influenced by the uncertainty of numerous power loads and distributed RES. As an important flexible resource, energy storage can participate in the economic dispatch of active distribution grids. Therefore, this paper presents an optimal economic dispatch method for enhancing the operational flexibility of ADN with distributed energy storage. Firstly, the energy storage and distributed power sources are modeled. Secondly, a robust optimal economic dispatch model is presented by characterizing the uncertainty of renewable energy output through the uncertainty set in order to fully utilize renewable energy and lower system operation costs. Thirdly, based on the models of energy storage and distributed power sources, a robust optimal scheduling model for the ADN with distributed energy storage is set up. Afterwards, the presented models are solved using an solver. Finally, by comparing the experimental results, the operating cost of the active distribution network using the robust optimal scheduling method of this paper and the traditional deterministic method are 313000 yuan and 28650000 yuan, respectively. The results of case study demonstrate the method's validity.