Two-layer multi-timescale chronological operation simulation for electric-hydrogen-ammonia coupled microgrid

To address the supply-demand imbalance problem by high proportion access of renewable energy, this paper proposes a two-layer multi-timescale chronological operation simulation for an electric-hydrogen-ammonia coupled microgrid. Considering the three different types of energy storage, the chronological operation simulation is divided into the upper-layer annual timescale and the lower-layer weekly timescale. The upper-layer determines the weekly state of charge profiles of ammonia energy storage, which serve as boundary constraints for the lower-layer operations. In the lower-layer, the operating cycle for hydrogen energy storage is set to 1 week while the operating cycle for electric energy storage is set to 1 day, generating hourly operational simulation through refined mathematical modeling of conversion devices. Through the simulation of equipment operation throughout the year, the future equipment output is guided to ensure the full utilization of renewable energy and the supply-demand balance of the system. Ultimately, the efficiency and superiority of the proposed method are verified within the two-layer multi-timescale chronological operation simulation. The results demonstrated that, compared with the single timescale and dual timescale simulations, our method reduces the annual total cost by 27.36% relative to the dual timescale approach. For the single timescale simulation, the annual total cost becomes negative, representing a net income.