Nonlinear model predictive control methodology for efficiency and durability improvement in a fuel cell power system

The main contribution of this work is the improvement of the efficiency of a PEMFC power system while guaranteeing conditions that also improve its durability. Adopting the NMPC scheme with the distributed parameter model and the nonlinear observer, the efficiency of the PEMFC-based system can be maximized guaranteeing at the same time the appropriate internal gas concentration profiles to avoid global and local hydrogen and oxygen starvation and proper membrane humidification.Peer ReviewedPostprint (author's final draft

Nonlinear predictive control for durability enhancement and efficiency improvement in a fuel cell power system

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In this work, a nonlinear model predictive control (NMPC) strategy is proposed to improve the efficiency and enhance the durability of a proton exchange membrane fuel cell (PEMFC) power system. The PEMFC controller is based on a distributed parameters model that describes the nonlinear dynamics of the system, considering spatial variations along the gas channels. Parasitic power from different system auxiliaries is considered, including the main parasitic losses which are those of the compressor. A nonlinear observer is implemented, based on the discretised model of the PEMFC, to estimate the internal states. This information is included in the cost function of the controller to enhance the durability of the system by means of avoiding local starvation and inappropriate water vapour concentrations. Simulation results are presented to show the performance of the proposed controller over a given case study in an automotive application (New European Driving Cycle). With the aim of representing the most relevant phenomena that affects the PEMFC voltage, the simulation model includes a two-phase water model and the effects of liquid water on the catalyst active area. The control model is a simplified version that does not consider two-phase water dynamics.Peer ReviewedPostprint (author's final draft

Proton exchange membrane fuel cell degradation prediction based on Adaptive Neuro-Fuzzy Inference Systems .

International audienceThis paper studies the prediction of the output voltage reduction caused by degradation during nominal operating condition of a PEM fuel cell stack. It proposes a methodology based on Adaptive Neuro-Fuzzy Inference Systems (ANFIS) which use as input the measures of the fuel cell output voltage during operation. The paper presents the architecture of the ANFIS and studies the selection of its parameters. As the output voltage cannot be represented as a periodical signal, the paper proposes to predict its temporal variation which is then used to construct the prediction of the output voltage. The paper also proposes to split this signal in two components: normal operation and external perturbations. The second component cannot be predicted and then it is not used to train the ANFIS. The performance of the prediction is evaluated on the output voltage of two fuel cells during a long term operation (1000 hours). Validation results suggest that the proposed technique is well adapted to predict degradation in fuel cell systems

Analyse des mécanismes de dégradation dans un système pile à combustible

International audienceLes systèmes pile à combustible (SPàC) sont considérés comme une solution viable et une alternative prometteuse autant pour des applications embarquées que stationnaires. Cela dit, ces systèmes doivent répondre à des critères essentiels à leur large développement, à savoir, coût, durabilité et fiabilité. Le présent travail se focalise sur l’aspect fiabilité du système pile à combustible. En effet, une meilleure compréhension des mécanismes de dégradation dans le SPàC permettra de développer les stratégies nécessaires à la réduction des dégradations au sein du SPàC et augmenter sa durée de vie utile. Une analyse des mécanismes de dégradation et leurs effets au niveau du SPàC a été faite dans le but de construire un arbre de défaillances le plus complet possible. Le SPàC étudié comprend le stack (membrane, couche catalytique, plaques bipolaires, couche de diffusion des gaz) le système d’alimentation en air (compresseur, capteurs, régulateurs, électrovannes), le système d’alimentation en hydrogène (capteurs, régulateurs, électrovannes) et le système de refroidissement (pompe de circulation, capteurs, électrovannes, régulateurs). Cette étude permettra de déduire les lois de propagation des défauts dans le SPàC qui permettront une meilleure estimation de sa durée de vie

Towards Resilient Fuel Cell Systems

International audienceHydrogen &amp; Fuel Cell systems are very promising clean systems to store intermittent energy and use it in green and decentralized electricity. For the large-scale deployment of these innovative hydrogen-based technologies, it is necessary to bring reliable systems to the market with competitive costs and lifetimes. For this purpose, solutions for tolerance to fault and resistance to degradation shall be developed. <br&gtThe solutions of interest are based mainly on analytical redundancy and are integrated into the system, using as much as possible, the system’s own resources. Thus, the stack is used as its own sensor. The different solutions developed include monitoring, diagnosis, prognosis, decision and control. The PEMFC system developed has the properties of resilient systems.&nbsp

Towards Resilient Fuel Cell Systems

International audienceHydrogen &amp; Fuel Cell systems are very promising clean systems to store intermittent energy and use it in green and decentralized electricity. For the large-scale deployment of these innovative hydrogen-based technologies, it is necessary to bring reliable systems to the market with competitive costs and lifetimes. For this purpose, solutions for tolerance to fault and resistance to degradation shall be developed. <br&gtThe solutions of interest are based mainly on analytical redundancy and are integrated into the system, using as much as possible, the system’s own resources. Thus, the stack is used as its own sensor. The different solutions developed include monitoring, diagnosis, prognosis, decision and control. The PEMFC system developed has the properties of resilient systems.&nbsp

Un cursus d’excellence pour former des ingénieurs-experts en matière d’hydrogène-énergie

National audienceLauréat du programme «&nbsp;Initiatives d’excellence en formationsinnovantes&nbsp;» mis en place par le gouvernement en 2012, lecursus Master en ingénierie (CMI) du réseau FIGURE a conduit à unetransformation profonde et durable des universités tant en termesde pratiques d’enseignement qu’en termes de qualité des formationsdispensées. Le CMI H3E est l’un de ces cursus&nbsp;; il a été crééen 2014 à l’Université de Franche-Comté pour former des cadresscientifiques et techniques aux métiers de l’hydrogène, desétudiants devant faire preuve de capacités d’innovation et d’uneouverture sociétale renforcées.<br /&gtBénéficiant d’un écosystème Formation-Recherche-Industrieexceptionnel ‒ deux grands laboratoires pionniers dans le domainede l’hydrogène, un tissu industriel fortement impliqué, une régionlabélisée «&nbsp;Territoire Hydrogène&nbsp;» dès 2016 et uneuniversité qui compte l’hydrogène parmi ses thèmes prioritaires deformation ‒, le CMI H3E œuvre à proposer une formation d’excellencepour une filière en plein essor. Il s’appuie pour cela sur uneoffre de formation se déclinant en deux masters (en ingénierieélectrique et en ingénierie thermique) et sur un corps professoralconstitué d’experts reconnus

Towards Resilient Fuel Cell Systems

International audienceHydrogen &amp; Fuel Cell systems are very promising clean systems to store intermittent energy and use it in green and decentralized electricity. For the large-scale deployment of these innovative hydrogen-based technologies, it is necessary to bring reliable systems to the market with competitive costs and lifetimes. For this purpose, solutions for tolerance to fault and resistance to degradation shall be developed. <br&gtThe solutions of interest are based mainly on analytical redundancy and are integrated into the system, using as much as possible, the system’s own resources. Thus, the stack is used as its own sensor. The different solutions developed include monitoring, diagnosis, prognosis, decision and control. The PEMFC system developed has the properties of resilient systems.&nbsp

A review of accelerated stress tests dedicated to proton exchange membrane fuel cells – Part I: Fuel cell component level

International audience<div id="abssec0010"&gt<p id="abspara0010"&gtVarious research are currently done about fuelcells. They can concern the application context, the <a href="https://www.sciencedirect.com/topics/engineering/fuel-cell-technology"title="Learn more about fuel cell technology from ScienceDirect's AI-generated Topic Pages"class="topic-link"&gtfuel cell technology</a&gt by itself or thesocio-economic bolts. This paper deals with <a href="https://www.sciencedirect.com/topics/engineering/fuel-cell-stack"title="Learn more about fuel cells stack from ScienceDirect's AI-generated Topic Pages"class="topic-link"&gtfuel cells stack</a&gt testing and especially theaccelerated stress testing. Long and expensive ageing tests areperformed to study the behavior of the fuel cell with the aim ofmaking it as robust as possible versus permanent degradation overtime. Accelerated stress tests should provide results faster asclassical ageing tests, thus inducing cost reduction. This paperreviews <a href="https://www.sciencedirect.com/topics/engineering/fuel-cell-component"title="Learn more about fuel cell component from ScienceDirect's AI-generated Topic Pages"class="topic-link"&gtfuel cell component</a&gt degradation, including<a href="https://www.sciencedirect.com/topics/engineering/degradation-mechanism"title="Learn more about degradation mechanisms from ScienceDirect's AI-generated Topic Pages"class="topic-link"&gtdegradation mechanisms</a&gt, and the acceleratedstress tests dedicated to all the constituting components (catalystlayer, membrane, gas diffusion layer and bipolar plates).Obviously, the harmonized accelerated stress tests given by theDepartment of Energy (DoE) are presented but all other recentaccelerated test protocols proposed in the literature are alsoreviewed. In addition, several tables are given to detail operatingconditions, specimen, characterization planning and a <a href="https://www.sciencedirect.com/topics/engineering/degradation-rate"title="Learn more about degradation rate from ScienceDirect's AI-generated Topic Pages"class="topic-link"&gtdegradation rate</a&gt that will be relevant andhelpful to converge with an optimal AST solution.</p&gt</div&g

Application of current steps and design of experiments methodology to the detection of water management faults in a proton exchange membrane fuel cell stack

International audienceWe apply a 25-1 fractional factorial Design of Experiments (DoE) test plan in order to discriminate the direct effects and interactions of five factors on the water management of a 500 We PEMFC stack. The stack is submitted to current steps between different operating levels and several responses are extracted for the DoE analysis. A strong ageing effect on stack and cell performances is observed. Therefore, in order to perform the DoE analysis, responses which values are too strongly affected by ageing are “corrected” prior to the analysis. A “virtual” stack, considered as “healthy”, is also “reconstructed” by “putting in series” the cells exhibiting very low performance drop.The results show that stacks and cells' resistivities are mostly impacted by direct effects of both temperature and cathodic inlet relative humidity and by compensating interaction between temperature and anodic overstoichiometric ratio. It also appears that two responses are able to distinguish a “healthy” stack from a degraded stack: heterogeneities in cell voltages and cell resistivities distributions. They are differently impacted by considered effects and interactions. Thus, a customised water management strategy could be developed, depending on the stack's state of health to maintain it in the best possible operating conditions