关键词:

"> 可再生能源, 离网型合成氨, 灵活性平衡, 混合整数线性规划模型, 优化调度

Abstract:

[Objectives] Off-grid wind–solar hydrogen production and ammonia synthesis systems suffer from power imbalance caused by renewable fluctuations. This paper proposes an optimal dispatch strategy considering flexibility supply–demand balance. [Methods] An off-grid model is developed with eight independently controlled electrolyzer trains, hydrogen storage, battery energy storage, and ammonia synthesis units. Flexibility demand (from wind–solar fluctuations and forecast deviations) and flexibility supply (from electrolyzer regulation, battery charge/discharge, and hydrogen storage buffering) are quantified. A multi-timescale mixed-integer linear programming (MILP) model is formulated to coordinate hourly electrolyzer control with 8-hour ammonia scheduling, and a baseline scenario is compared with a flexibility-coordinated scenario. [Results] Annual results show that the curtailment rate decreases from 26.54% to 15.53%, annual ammonia production increases from 52,900 t to 87,200 t, and electrolyzer utilization improves from 81.3% to 88.8%. Typical-day analysis indicates reduced net-load fluctuations and more stable power support for ammonia synthesis. [Conclusions] Jointly considering flexibility constraints and optimizing hydrogen storage participation can significantly improve renewable utilization and the techno-economic performance of off-grid wind–solar hydrogen–ammonia systems.

Key words: renewable energy, off-grid ammonia synthesis, flexibility balance, milp, optimal scheduling