TT01 Utility-Scale Hydrogen Electrolyzers: Fundamentals, Modelling, Grid Support Services, and Operation (Part I)

Abstract
There are major discussions worldwide on how the production of clean fuels, such as hydrogen, could facilitate the whole-energy system decarbonization. From a power system perspective, green hydrogen production results in massive grid integration of electrolyzers, that needs to be considered in power system analysis. This tutorial presents the modelling foundations of utility-scale hydrogen electrolyzers with alkaline and proton exchange membrane (PEM) technology, including electrolysis stack models, power electronics interface (PEI) and control, thermodynamics, hydrogen production formulations, and operational constraints in downstream hydrogen process/buffer, required for system-level dynamic studies in both transmission and distribution grids. Possible PEIs for grid integration of electrolyzers will be discussed, along with the associated control schemes in particular grid-forming load control. Finally, it will be discussed how and to what extent electrolysis plants could contribute to system stability and resilience, along with potential challenges and requirements in the context of real-life events and systems.

Course Outline (duration 4h)

1. Hydrogen electrolyzers in power system studies: Introduction (15 minutes)
2. Modelling of electrolysis stack (PEM and alkaline technologies) (30 minutes)
   a. Electrolysis stack modelling modelling
   b. Hydrogen production sub-model
   c. Thermodynamics of electrolysis technologies
   d. Stack voltage-current-efficiency nonlinearities10 minutes Q&A followed by 5 minutes break
3. Power-electronics interface and control of electrolyzers (45 minutes)
   a. Grid-following control
   b. Virtual synchronous machine control
   c. Grid-forming load concept and its application to hydrogen electrolyzer control10 minutes Q&A followed by 5 minutes break
4. System dynamic support from electrolyzers: modelling, benefits, and challenges (45 minutes)
   a. Frequency support services, including virtual inertia, fast frequency response, and frequency regulation
   b. Voltage control and reactive power support
   c. Grid-forming services10 minutes Q&A followed by 5 minutes break
5. Real-life examples and numerical/simulation-based exercises (45 minutes)
6. Concluding remarks (15 minutes)

Instructors

Mehdi Ghazavi Dozein
The University of Melbourne, Australia
mehdi.ghazavidozein@unimelb.edu.au

Oriol Gomis-Bellmunt
Universitat Politecnica de Catalunya (UPC), Spain
oriol.gomis@upc.edu

Marc Cheah Mañe
Universitat Politecnica de Catalunya (UPC), Spain
marc.cheah@upc.edu