Scaling Digital Real-Time Models of Alkaline Electrolyzers for Power Grid Integration

This paper presents a framework to scale alkaline electrolyzer models used in digital real-time simulation environments. Models for 100-kW, 1-MW, and 1.5-MW electrolyzers are presented, emphasizing key parameters at the cell and stack levels. Two scenarios are simulated to evaluate the performance of the models developed with this framework: stand-alone operation and grid-connected operation. This framework helps scale the electrolyzer models in digital real-time simulators used for hydrogen production in various power-to-X applications and their role in grid flexibility. In addition, improvements in the converter modeling and DC/DC integration are discussed. These improvements will enhance the stability of the models and their reusability for grid impact studies. Also addressed are key limitations, including simplified power electronics modeling, the absence of experimental validation, and economic feasibility considerations.