Abstract:

The configuration of electricity-hydrogen hybrid energy storage in active distribution networks is of vital importance for enhancing the economic efficiency of electricity usage, promoting the consumption of renewable energy, reducing voltage fluctuations, and ensuring the balance between supply and demand as well as system stability. Firstly, an active distribution network operation framework containing electricity-hydrogen hybrid energy storage system is designed, and an electric-hydrogen hybrid energy storage model in the distribution network domain is constructed. Then, an upper-level optimization model is constructed to minimize the comprehensive electricity cost, and a lower-level optimization model is established with the goals of minimizing the wind and solar curtailment rate, voltage fluctuation rate, grid purchase fluctuation, and the total load fluctuation. Finally, a modified IEEE 33-node distribution network is used as a case study to validate the effectiveness of the proposed model. The results demonstrate that the model can achieve optimal capacity configuration for electricity-hydrogen hybrid energy storage system, and optimal dispatch of the active distribution networks. Compared to scenarios without energy storage or with single-medium energy storage, the hybrid electricity-hydrogen system proves to be more economically viable and enhances the self-regulating capability of the active distribution networks. Time-of-use electricity prices and seasonal characteristics collectively drive the coordinated operation of the electricity-hydrogen hybrid energy storage system, forming a synergistic dispatching mode characterized by "electrochemical storage providing rapid response + hydrogen storage enabling long-duration regulation."

Key words: active distribution networks, electricity-hydrogen hybrid energy storage, capacity allocation, two-layer optimization