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Confronted by the energy and environmental challenges, fuel cells raise a lot of hope. Fuel cells are expected to be an important power source in the future, and the proton exchange membrane fuel cell (PEMFC) is one of the potential candidates, being highly suitable for certain applications. The electrochemical components, especially a fuel cell, are naturally multidisciplinary components rather well adapted to this approach: chemistry, electrochemistry, thermal and electrical engineering are involved. We propose a PEMFC model using the bond graph method. This model takes into account the different physicochemical phenomena in a fuel cell. The modeling of the activation layer (AL) and gas diffusion layer (GDL) of the cathode side is highlighted. This model is then validated by an experimental work where we have used a 1.2-kW power PEMFC of the Nexa type from Ballard. The static characteristics of the fuel cell obtained by simulation are in good agreement with those of experiments and also from the literature. The PEM fuel cell has given rise to many research and development activities around the world. The technology is changing rapidly and strongly. This energy converter, both clean and efficient, can convert the chemical energy of hydrogen-predicted as the energy source of the future by leading specialists in view of its specific energy that is three times greater than gasoline-into electrical energy directly usable and thermal energy that it is possible to enhance.The fuel cell involves the oxidation-reduction reaction between hydrogen and oxygen to form water, electricity, and heat [5]. A PEMFC is composed of a stack of electrochemical cells in

This paper addresses the problem of bond graph methodology as a graphical approach for modeling renewable and electrochemical sources, particularly fuel cells. The purpose is to highlight the bond graph approach in order to model a PEM cell model, as a first step, and to control the incoming hydrogen and oxygen flows to its electrodes as a second step. The adapted control is conventional based on a PID regulator.

In this paper, a robust fault diagnosis for a refrigerator compartment containing a quantity of ice using the bond graph (BG) approach is performed by linear fractional transformations (LFTs). The BG model describes heat transfers supported by the amount of ice placed in the refrigerator compartment, as well as a water container. The LFT modeling of BG elements offers advantages from the point of view of structural analysis and data processing implementation. We have introduced four faults, which consist of ice temperature rise, water leakage, insulation failure at the hot walls of the refrigerator and an increase of the internal temperature due to poor door sealing. The faults are in the form of additional heat fluxes. The simulation results show the effectiveness of the proposed method for detecting and localizing faults. In addition, the lack of door sealing has the most influence on the temperatures in the internal cooling space, water, and ice compared to the other faults.

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