Fuel Cell Circuit of Hydrogen Storage Systems: Small-Signal Admittance-Based Analytical (MATLAB) and Simulation (Simulink) Models for DC Grid Stability Studies

The MATLAB and Simulink models presented in this repository are related to the following publication: O. Cartiel et al., “Admittance Modelling of Fuel Cell Circuits for Small-Signal Stability Assessment of Hydrogen Storage Systems in DC-grids,” in International Journal of Electrical Power & Energy Systems, vol. XXX, Sept. 2026, doi: XXXXX. This repository provides analytical and simulation models of fuel cell circuits developed for stability assessment of hydrogen storage systems connected to multi-energy DC power grids. The analytical model is implemented in MATLAB and enables frequency-domain characterisation of the fuel cell circuit dynamics through its small-signal admittance-based representation. The model is suitable for studying resonance phenomena and damping characteristics arising from interactions between fuel cell DC/DC converters and DC grids. In addition, a detailed time-domain simulation model implemented in Simulink is included. This model has been used to validate the analytical formulation under representative operating conditions, following the SARA (Simulation-based Admittance Response Analysis) validation workflow. The analytical model is intended to support frequency-domain stability analysis of large-scale multi-energy DC systems with fuel cell circuits. The simulation model allows time-domain studies of the dynamic interactions between fuel cell DC/DC converters and DC grids. The repository enables the investigation of oscillatory instabilities and the influence of fuel cell circuit parameters and DC grid characteristics on system stability. This repository supports reproducibility of the results presented in the associated journal publication and provides a reusable modelling framework for researchers and engineers working on hydrogen storage systems, DC grids, power electronics, and impedance/admittance-based stability analysis.