Distributionally Robust Optimization Configuration of Microgrid Hybrid Energy Storage Based on Reliability
Abstract
To improve the reliability of microgrid operation and the capability for off-grid autonomous operation, this study proposes a robust reliability-based optimal configuration method for microgrid hybrid energy storage systems. Firstly, the operational characteristics of the hydrogen energy storage system are analyzed, and combined with the cooperative mechanism of the hydrogen energy storage and distributed power supply systems, the operation architecture of the microgrid electro-hydrogen coupling system is constructed. Secondly, according to the electro-hydrogen coupling characteristics and adjustment capability, a two-stage distributionally robust optimization configuration model of electro-hydrogen hybrid energy storage is constructed. In the first stage, the minimum investment and operation cost of the microgrid is the optimization goal. The optimal configuration model for the equipment capacity in the microgrid is constructed, and the distributed photovoltaic, wind turbine, battery, hydrogen storage tank, hydrogen fuel cell and electrolytic cell in the microgrid are fixed. In the second stage, according to the results of the capacity optimization configuration in the first stage, the operation reliability of the microgrid is taken as the optimization objective; 168 h is set as the operation cycle, and the extreme operation scenario for the new energy output from the microgrid is assumed to provide the capacity optimization boundary for the upper layer. Finally, the model is solved by the constraint generation algorithm and analyzed by an actual microgrid in a given area. The quantitative results demonstrate the validity of the proposed method: compared to systems without hydrogen energy storage, the duration of the continuous islanded operation is increased from approximately 302 h to 529 h (an improvement of approximately 75.2%), and the load-shedding duration is reduced from approximately 35 h to 7 h (an approximately 80% reduction).