A Dynamic Multi-Physical Proton Exchange Membrane Fuel Cell Stack Surrogate Model with Empirical Ageing

In the context of alternative propulsion technology, Proton Exchange Membrane Fuel Cells (PEMFCs) are relevant in conjunction with batteries in extending operational capabilities of Electric Vehicles (EVs). In the scope of this work, a sufficiently detailed dynamic multi-physical coupled surrogate model of a PEMFC stack is designed in the Modelica standard. The novel factor of this work is the inclusion of parametrizable empirical ageing and membrane hydration models for the PEMFC stack based on literature. Using the PEMFC stack surrogate model, various load profiles can be simulated, and the corresponding state evolution can be estimated. Based on this surrogate model too chain, several objectives can be solved:
• Dimensioning of the PEMFC stack according to the load profile.
• Dynamic response of the PEMFC stack and its feasibility for a particular load profile.
• Degradation stress estimation of the PEMFC stack based on a load profile.
• Diagnostics and characterization of Hardware-in-Loop (HiL) PEMFC systems.
• Sensitivities of degradation effects based on system operation states.
Due to the surrogate model being built in the Modelica standard, exporting Functional Mock-up Units (FM Us) become trivial and allows for the surrogate model to be modular and used in almost any software simulation toolchain. Another consideration is the parameterization, where this work also provides insight into locally parametrizing various sub-systems of the model. This ensures easier and faster parameter estimation and can be used for the real-time diagnostics of PEMFC systems in a HiL setting. In this article, a Software-in-Loop (Sil) demonstration is performed for a dynamic load cycle in a virtual testbench setting to evaluate the system.