Modelling, simulation and analysis of a PEM electrolysis system

Abstract In this paper, the issues related to the coupling of a PEM electrolysis system to intermittent electrical sources are studied through a modelling process. A bibliographic analysis was carried out to identify existing models. State of the art highlighted that, although it is critical for the conception of such systems, only a few models take into account the dynamic of the whole system including balance of plant. Therefore, a model was developed under Bond Graph formalism. After a fitting process, the model was proved to describe accurately the dynamic behaviour of a semi-industrial PEM electrolysis system (25 kW). Among its numerous advantages regarding multiphysic systems modelling, the structural properties of Bond Graph formalism allow to obtain data about observability, controllability, monitorability of the system. Moreover, by providing a good representation of the whole system, the model is suitable for control and model-based diagnostic. Thus, it is a powerful tool to improve the conception of PEM electrolysis systems powered by intermittent electrical sources.