Observer-based output feedback control with application to PEMFC

Proton Exchange Membrane Fuel Cells (PEMFCs) are electrochemical devices that convert hydrogen chemical energy into electric power energy, and are considered a suitable alternative for efficient and environmentally sustainable energy conversion in many applications. Model-based controls, aiming to increase the efficiency of the energy conversion, require the complete knowledge of the state. This can be achieved by the use of a suitable state estimator providing the unmeasured or not directly accessible variables. In this paper, it is proposed an observer-based approach to control the oxygen excess ratio of a PEMFC, whose regulation is recommended to achieve longer lifetime and higher efficiency. The control scheme allows to set independently the control and the observer parameters thanks to the special structural properties of the model system that guarantee the separability of estimation and feedback control algorithms.