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La EEBE de la UPC está desarrollando un laboratorio para optimizar la producción y almacenamiento de hidrógeno utilizando energía solar. El proyecto busca maximizar la eficiencia energética y reducir los costos operativos mediante simulaciones computacionales que modelan la generación solar, el flujo de hidrógeno y los ciclos de compresión. Además, se evalúan diferentes escenarios para balancear el uso de energía solar y la red eléctrica, y se calculan los costos de inversión (CAPEX) y operación (OPEX) para identificar las configuraciones más rentables. El trabajo también incluye un análisis detallado de las especificaciones técnicas de los componentes del laboratorio, proporcionando una comprensión integral de sus especificaciones y funcionamiento.

The goal of increasing efficiency and durability of fuel cells can be achieved through optimal control of their operating conditions. In order to implement such controllers, accurate and computationally efficient fuel cell models must be developed. This work presents a hybrid (physics-based and data-driven), control-oriented model for approximating the output voltage of proton exchange membrane fuel cells (PEMFCs) while operating under dynamical conditions. First, a physics-based model, built from simplified electrochemical, membrane dynamics and mass conservation equations, is developed and validated through experimental data. Second, a data-driven, neural network (echo state network) is trained, fitted and tested with the same dataset. Then, the hybrid model is formed as a parallel structure, where the simplified physics-based model and the trained data-driven model are merged through an algorithm based on Gaussian radial basis functions. The merging algorithm compares the output of both single models and assigns weights for computing the prediction of the hybrid result. The proposed hybrid model structure is successfully trained, validated and tested with an experimental dataset originating from fuel cells within an automotive PEMFC stack. The hybrid model is assessed through the mean square error index, with the result of a low tracking error., Peer Reviewed, Postprint (published version)

© 2023 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission., In this paper, a fuel cell system supervisory controller is developed for a fuel cell-based hybrid electric vehicle to safely control the interactions between powertrain components, maximize efficiency and minimize the degradation of the fuel cell. The proposed fuel cell supervisory controller includes three main elements: a state machine, an optimal setpoint generator and a power limit calculator. The state machine, as the top layer of the supervisory controller, is responsible for coordinating the various subsystems of the fuel cell, including the three subsystems, anode, cathode, thermal, and the DC/DC converter. The primary purpose of the state machine is to ensure global control over these subsystems as well as facilitate communication between the fuel cell system, diagnosis system, and Vehicle Control Unit (VCU). The state machine not only allows for the appropriate transitions between states but also governs the fuel cell system operation in all its different operating states such as Start-up, Shutdown and Run. The optimal setpoint generator is responsible for determining the operating conditions of the fuel cell system that maximizes the system's efficiency. It is designed by taking into account the comprehensive model of the fuel cell stack, considering manufacturing constraints, and incorporating the compressor map which then provides the optimal setpoints for all the subsystems' local controllers. A power limit calculator is also developed to compute the stack available power and feeds this information to the energy management system in the VCU. This information is used by the VCU to split the requested power between the fuel cell and the battery. The experimentally validated stack model and the complex model of the subsystems based on the Inn-Balance project data are used in the simulation. Furthermore, the subsystems' local controllers used in the MATLAB-Simulink were validated in a real vehicle test bench. The Common Artemis 130 km/h Driving Cycle (CAD, This work was supported in part by the Spanish State Research Agency through the Maria de Maeztu Seal of Excellence to IRI (MDM-2016-0656), and and in part by the Fuel Cells and Hydrogen 2 Joint Undertaking under Grant INN-BALANCE 735969. This Joint Undertaking receives support from the European Union’s Horizon 2020 research and innovation program and Hydrogen Europe and N.ERGHY . Finally, the work acknowledges the support of the MAFALDA project funded by the Spanish Ministry of Science and Innovation (PID2021-126001OB-C31)., Peer Reviewed, Postprint (author's final draft)

El següent treball de final de grau consisteix en un projecte sobre la instal·lació d'una estació de proves d'una pila electroquímica d'alta temperatura de petita escala. Per aconseguir-ho, s'ha realitzat un estudi tant de la utilitat com del funcionament de les piles electroquímiques per entendre les seves condicions d'operació, els requisits i protocols per a la posada a punt. A partir d'aquí s'ha dissenyat tant el sistema de gasos que alimenta la pila, implicant-la investigació i selecció dels components necessaris per a això. A més, s'exposa com s'ha d'utilitzar l'estació incloent les mesures de seguretat, les connexions elèctriques, el control per programari i les connexions d'alimentació de la pila. També, es realitza el càlcul electroquímic sobre el nombre màxim de cel·les que pot suportar el sistema segons les seves característiques i el càlcul tèrmic del forn per saber els temps entre intervals de temperatura i el consum elèctric. Finalment, es realitza un estudi econòmic per avaluar el cost del projecte i poder veure quines són les parts amb el cost més elevat per poder-les optimitzar en un futur., El siguiente trabajo de final de grado consiste en un proyecto sobre la instalación de una estación de pruebas de una pila electroquímica de alta temperatura de pequeña escala. Para ello se ha realizado un estudio tanto de la utilidad como del funcionamiento de las pilas electroquímicas para entender sus condiciones de operación, los requisitos y protocolos para la puesta a punto. A partir de aquí se ha diseñado tanto el sistema de gases que alimenta la pila, implicando la investigación y selección de los componentes necesarios para esta. Además, se expone como se debe utilizar la estación incluyendo las medidas de seguridad, las conexiones eléctricas y el control por software También, se realiza el cálculo electroquímico sobre el número máximo de celdas que puede soportar el sistema según sus características y el cálculo térmico del horno para saber los tiempos entre intervalos de temperatura y el gasto eléctrico Por último, se realiza un estudio económico para evaluar el coste del proyecto y poder ver cuáles son las partes con el coste más elevado para poderlas optimizar en un futuro., The following bachelor's thesis project consists of setting up a small-scale high-temperature fuel cell test station. To accomplish this, a study has been conducted on both the usefulness and operation of fuel cells to understand their operating conditions, requirements, and setup protocols. From here, the gas system that feeds the cell has been designed, involving research and selection of the necessary components. Additionally, instructions on how to use the station are provided, including safety measures, electrical connections, software control, and power supply connections for the cell. Furthermore, electrochemical calculations are performed to determine the maximum number of cells the system can support based on its characteristics, and thermal calculations for the furnace are conducted to determine temperature interval times and electrical consumption. Finally, an economic study is carried out to assess the project's cost and identify the parts with the highest costs for potential optimization in the future.

© 2023 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)., This paper presents the development and implementation of a system supervisory controller in a hydrogen-based fuel cell electric vehicle. The controller's primary function is to ensure the safe control of the fuel cell system processes while facilitating coordination among various subsystems, including the balance of plant subsystems, vehicle control unit, diagnosis unit, and powertrain. The supervisory controller comprises of three primary parts: a State Machine, an Optimal Setpoint Generator, and a Power Limit Calculator. The State Machine, which serves as the central part of the supervisory controller, coordinates the fuel cell system's different operational states, including the complex processes of start-up and shutdown. To maximize the fuel cell system's efficiency and minimize the stack's degradation, the Optimal Setpoint Generator produces the subsystem's setpoints by solving an optimization problem and considering the manufacturer's requirements. The Power Limit Calculator assesses the stack's power output capability and calculates the current setpoint for the DC/DC converter. It then provides this data to the Energy Management System (EMS), which oversees the distribution of power between the fuel cell system and the batteries. The proposed fuel cell system supervisory controller is verified using the Worldwide Harmonized Light Vehicles Test Cycles (WLTC) in a real-world car. The designed control structure is implemented in a prototype hydrogen-based electric car at both PowerCell and CEVT facilities under the framework of the INN-BALANCE Horizon 2020 European project., This work was supported in part by the Spanish national project DOVELAR (RTI2018-096001-B-C32, MINECO/FEDER) also in part by the Fuel Cells and Hydrogen 2 Joint Undertaking under Grant INN-BALANCE 735969. This Joint Undertaking receives support from the European Union's Horizon 2020 research and innovation program and Hydrogen Europe and N. ERGHY, Peer Reviewed, Postprint (published version)

Aquest projecte parteix de la problemàtica cada vegada més evident sobre els menjars vegetarians. El cost d'aquests i la despesa energètica que produeixen. Per donar una solució al problema, en aquest treball es fa l'estudi de com fabricar un bioreactor especialitzat en la producció d'un fong en específic. Un fong comestible i amb grans qualitats nutritives. En aquest treball de final de grau es farà la millora d'un prototip de bioreactor de plàstic, el qual s'adaptarà per poder-lo fer funcional intentant que les peces siguin de compra i el màxim assequible possible. Per altra banda, es durà a terme un estudi dels paràmetres de medició necessaris i es donarà una solució assequible i funcional pel seu control. Finalment, vull afegir-vos que aquest treball és l'indicat per a vosaltres si esteu buscant solucions alternatives i assequibles per fabricar les parts principals que componen els bioreactors convencionals., Este proyecto parte de la problemática cada vez más evidente sobre las comidas vegetarianas. El coste de estos y el gasto energético que producen. Para dar una solución al problema, en este trabajo se hace el estudio de como fabricar un biorreactor especializado en la producción de un hongo en específico. Un hongo comestible y con grandes calidades nutritivas. En este trabajo de final de grado se hará la mejora de un prototipo de biorreactor de plástico, el cual se adaptará para poderlo hacer funcional intentando que las piezas sean de compra y el máximo asequible posible. Por otro lado, se llevará a cabo un estudio de los parámetros de medición necesarios y se dará una solución asequible y funcional por su control. Finalmente, quiero añadiros que este trabajo es el indicado para vosotros si estáis buscando soluciones alternativas y asequibles para fabricar las partes principales que componen los biorreactores convencionales., This project starts from the increasingly obvious problem of vegetarian meals. The cost of these and the energy expenditure they produce. To provide a solution to the problem, this work involves studying how to manufacture a bioreactor specializing in the production of a specific fungus. An edible fungus with high nutritive qualities. In this end-of-graduate work, an improved plastic bioreactor prototype will be adapted to make it functional by trying to make the parts as affordable and purchaseable as possible. On the other hand, a study will be carried out into the necessary mediation parameters and an affordable and functional solution will be provided for their control. Finally, I would like to add that this work is the right one for you if you are looking for alternative and affordable solutions to manufacture the main parts that make up conventional bioreactors.

El meu treball de final de grau consisteix en el disseny i la creació de un prototip de bioreactor. El prototip ha de complir una sèrie d’especificacions ja que a de cara al futur s’ha de poder construir un bioreactor amb altres tipus de materials i de dimensions més grans per poder desenvolupar l’aplicació per la qual està pensat, la creació de menjar mitjançant el desenvolupament i creixement d’un microorganisme del regne fungi. En aquest document explico les característiques que ha de tenir el meu bioreactor, com l’he dissenyat i adaptat perquè compleixi aquestes característiques, els problemes que m’han anat sorgint al llarg del treball i quines solucions hi he pogut aplicar. A més, també detallo de quins components està fet i com els he anat ajuntant fins a arribar a construir amb èxit un prototip funcional que serveix per a realitzar tot tipus de proves i experiments. En resum, puc considerar que el procés de disseny i creació del bioreactor ha set bo i que el resultat obtingut és funcional i em servirà de cara a un futur., Mi trabajo de fin de grado consiste en el diseño y creación de un prototipo de biorreactor. El prototipo debe cumplir una serie de especificaciones ya que de cara al futuro se debe poder construir un biorreactor con otros tipos de materiales y de mayores dimensiones para poder desarrollar la aplicación para la que está pensado, la creación de comida mediante el desarrollo y crecimiento de un microorganismo del reino fungi. En este documento explico las características que debe tener mi biorreactor, cómo lo he diseñado y adaptado para que cumpla estas características, los problemas que me han ido surgiendo a lo largo del trabajo y qué soluciones he podido aplicar. Además, también detallo de qué componentes está hecho y cómo los he ido juntando hasta llegar a construir con éxito un prototipo funcional que sirve para realizar todo tipo de pruebas y experimentos. En resumen, puedo considerar que el proceso de diseño y creación del biorreactor ha sido bueno y que el resultado obtenido es funcional y me servirá de cara a un futuro., My thesis consists of the design and creation of a bioreactor prototype. The prototype must meet a series of specifications since in the future it must be possible to build a bioreactor with other types of materials and of larger dimensions to be able to develop the application for which it is intended, the creation of food through the development and growth of a microorganism of the fungi kingdom. In this document I explain the characteristics that my bioreactor must have, how I have designed and adapted it so that it meets these characteristics, the problems that have arisen over the course of my work and what solutions I have been able to apply. In addition, I also detail what components it is made of and how I have been putting them together until I have successfully built a functional prototype that can be used to carry out all kinds of tests and experiments. In summary, I can consider that the process of designing and creating the bioreactor has been good and that the result obtained is functional and will serve me in the future.

La UPC está construyendo un laboratorio autónomo de hidrógeno en el campus del Besós. Estas instalaciones están provistas de electrolizadores para producir su propio hidrógeno a partir de la electricidad generada por un sistema fotovoltaico, así como de la red. El objetivo de esta tesis es elaborar un algoritmo capaz de controlar los elementos del sistema para asegurar el abastecimiento de hidrógeno del laboratorio, a la vez que minimice tanto la degradación de los elementos del sistema, como los costes económicos. Este algoritmo se ha desarrollado en Matlab siguiendo una estructura de decisiones lógicas con forma de árbol de decisiones. Para comprobar la efectividad del algoritmo, se han realizado simulaciones variando la potencia fotovoltaica producida, los perfiles de demanda de hidrógeno y el hidrógeno almacenado al inicio de la simulación, The UPC is building an autonomous hydrogen laboratory in the Besós campus. In order to produce its own hydrogen, these installations contain electrolizers fueled by a photovoltaic system and by the electrical grid. The objective of this thesis is to create an algorithm able to control the elements of the system in order to ensure the supply of hydrogen for the laboratory while minimizing the degradation of the different elements and the economical cost. The algorithm has been developed in Matlab following logical choices and shaped as a decision tree. For the purpose of find out the effectiveness of the algorithm, a few simulations has been done varying the solar radiation, the hydrogen demand profiles and the amount of hydrogen stored at the beginning of the simulation, La UPC està construint un laboratori autònom d'hidrogen al campus del Besòs. Aquestes instal·lacions estan proveïdes d'electrolitzadors per produir el seu propi hidrogen a partir de l'electricitat produïda per un sistema fotovoltaic, o bé de la xarxa. L'objectiu d'aquesta tesi és elaborar un algoritme capaç de controlar els elements del sistema per assegurar l'aprovisionament d'hidrogen del laboratori a la vegada que minimitzi tant la degradació dels elements del sistema, com els costos econòmics. Aquest algoritme s'ha desenvolupat amb Matlab seguint una estructura de decisions lògiques amb forma d'arbre de decisions. Per comprovar l'efectivitat de l'algoritme, s'han realitzat simulacions variant la potència fotovoltaica produïda, els perfils de demanda d'hidrogen i l'hidrogen guardat a l'inici de la simulació

Les microxarxes energètiques necessiten de tècniques de control especialitzades per a poder operar de manera eficient, tant en termes econòmics com tècnics. Una de les tècniques que més s'ha desenvolupat últimament és la tecnologia MPC. L'objectiu de la present tesi és elaborar una estratègia de control predictiu per a controlar la planta pilot que proveirà d'hidrogen al laboratori d'hidrogen del campus Besós de la UPC. S'ha realitzat una recerca de l'estat de l'art actual i s'ha desenvolupat un model MPC, el qual es contrasta amb un esquema de control de regles lògiques, basat en els nivells de pressió dels tancs. El model emprat per a definir els elements és lineal i amb la condició de definir el comportament d'estats dels electrolizadors i del compressor s'empra la formulació MLD. Es realitzen simulacions representatives de setmanes dels diferents períodes estacionals anuals variant el nivell de potència fotovoltaica instal·lada. Després de realitzar les simulacions, es conclou que la tècnica MPC ofereix múltiples avantatges respecte al control per regles lògiques, tant en estalvi econòmic a causa d'una millor gestió dels equips com en una millora operativa de la pròpia planta, Las microrredes energéticas necesitan de técnicas de control especializadas para poder operar de forma eficiente, tanto en términos económicos como técnicos. Una de las técnicas que más se ha desarrollado últimamente es la tecnología MPC. El objetivo de la presente tesis es elaborar una estrategia de control predictivo para controlar la planta piloto que abastecerá de hidrógeno al laboratorio de hidrógeno del campus Besós de la UPC. Se ha realizado una investigación del estado del arte actual y se ha desarrollado un modelo MPC, el cual se contrasta con un esquema de control de reglas lógicas, basado en los niveles de presión de los tanques. El modelo empleado para definir los elementos es lineal y con tal de definir el comportamiento de estados de los electrolizadores y del compresor se emplea la formulación MLD. Se realizan simulaciones representativas de semanas de los diferentes periodos estacionales anuales variando el nivel de potencia fotovoltaica instalada. Tras realizar las simulaciones, se concluye que la técnica MPC ofrece múltiples ventajas respecto al control por reglas lógicas, tanto en ahorro económico debido a una mejor gestión de los equipos cómo en una mejora operativa de la propia planta, Energy microgrids require specialized control techniques in order to operate efficiently, both in economic and technical terms. One of the techniques that has been developed the most lately is Model Predictive Control (MPC) technology. The objective of this thesis is to develop a predictive control strategy to control the pilot plant that will supply hydrogen to the hydrogen laboratory of the Besós campus of the UPC. An investigation of the current state of the art has been carried out and an MPC model has been developed, which is contrasted with a control scheme of logical rules, based on the pressure levels of the tanks. The model used to define the elements is linear and to define the behavior of the states of the electrolyzers and the compressor, the Mixed Logical and Dynamical (MLD) formulation is used. Representative simulations of weeks of the different annual seasonal periods are carried out and varying the level of installed photovoltaic power. After carrying out the simulations, it is concluded that the MPC technique offers many advantages over control by logical rules, both in economic savings due to better equipment management and in an operational improvement of the equipment usage, Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.4 - Per a 2030, modernitzar les infraestructures i reconvertir les indústries perquè siguin sostenibles, usant els recursos amb més eficàcia i promovent l’adopció de tecnologies i processos industrials nets i racionals ambiental­ment, i aconseguint que tots els països adoptin mesures d’acord amb les capacitats respectives

Increasing efficiency and durability of fuel cells can be achieved through advanced model-based optimal control of its operating conditions, and the efficient online estimation of fuel cell parameters and internal states is fundamental for the implementation of such advanced controllers. The exchange current density is a driving parameter of performance for the catalyst layer of proton exchange membrane fuel cells (PEMFC). This study presents a control-oriented, stochastic filtering approach for online, continuous estimation of the exchange current density in low-temperature PEMFCs. The fuel cell is framed as a Markov model where the exchange current density is posed as the stochastic hidden state. The physics-based static equation of the exchange current density is converted into a state transition equation. This transition equation and the equation for cell voltage are used in the stochastic state estimator to approximate the posterior probability distribution of the exchange current density. In order to highlight the usefulness of the approach, the estimated value of the exchange current density is used to approximate the trend of the electrochemical active surface area (ECSA) in the catalyst layer and train a nonlinear auto-regressive model. This data-driven model is used to forecast the evolution in the ECSA associated with long-term degradation. The estimation algorithm is successfully implemented and tested in two different experimental datasets., Peer Reviewed, Postprint (published version)

La robòtica d’assistència domèstica inclou un gran nombre de problemàtiques que requereixen una solució per a atendre, amb la màxima flexibilitat, a l’usuari. Un robot ha de poder ser capaç de tractar i manipular un gran nombre d’objectes dins d’una casa, ja siguin rígids o deformables Entre aquests objectes habituals en una llar hi ha les peces de roba, les quals presenten una alta complexitat de categorització a causa de la dificultat en modelitzar els possibles estats en els que es poden trobar (potencialment infinits degut a la seva deformabilitat) per a tasques com ara guardar la roba, plegar, allisar o simplement transportar d’un punt a l’altre. Aquest treball presenta una metodologia per a discernir, a partir d’una imatge, l’existència d’un pantaló, i la seva classificació en quatre estats preestablerts, separant aquests entre pantalons que es troben completament de dins cap a fora o amb el costat correcte cap enfora, i determinant si la peça es troba cap per amunt o cap per avall. Els resultats obtinguts demostren un mètode eficaç i ràpid per a la seva classificació, observant les diferents problemàtiques i aportant un conjunt de solucions i millores aplicables per a treballs futurs., La robótica de asistencia doméstica conlleva un gran número de problemáticas que requieren una solución para atender, con la máxima flexibilidad, al usuario. Un robot debe poder ser capaz de tratar y manipular un gran número de objetos dentro de una casa, ya sean rígidos o deformables. Entre estos objetos se encuentran las prendas de vestir, las cuales presentan una alta complejidad de categorización debido a la dificultad en modelizar los posibles estados (potencialmente infinitos debido a su deformabilidad) en los que se pueden encontrar para tareas como guardar la ropa, plegar, alisar o simplemente transportarla de un punto a otro. Este trabajo presenta una metodología para discernir, a partir de una imagen, la existencia de un pantalón, y su clasificación en cuatro estados preestablecidos, separando estos entre pantalones que se encuentran completamente de dentro hacia fuera o con el lado correcto, exterior, hacia afuera, y determinando si la pieza se encuentra boca arriba o boca abajo. Los resultados obtenidos demuestran un método eficaz y rápido para su clasificación, observando las diferentes problemáticas y aportando un conjunto de soluciones y mejoras aplicables para trabajos futuros., Assistive robots address a large number of problems that require a solution to help, with the maximum flexibility, the user. A robot must be able to treat and manipulate a large number of objects inside a house, whether they are rigid or deformable. Among such objects there are garments, which have a high complexity of categorization due to the difficulty to model the possible states (potentially infinite, due to their deformability) in which they can be found for tasks such as storing clothes, folding, smoothing, or simply transporting them from one point to the other. This work presents a methodology to discern, from an image, the existence of pants, and their classification in four pre-established states, separating these between pants that are completely inside-out or right-side out and determining whether the pieces are facing upwards or downwards. The results obtained demonstrate an effective and fast method for classification, observing the different problems, and providing a set of solutions and improvements applicable for future work.

The objective of the present work is to explore and validate autoregressive, control oriented models models Proton Exchange Membrane Fuel Cells coperatinf under dynamic condditions. Autoregressive models have several advantages: they are obtained solely from input-output signals, have low computational cost, simple structure and a small number of parameters. Four datasets from experiments in static and dynamic operating conditions are used to estimate an validate the models, each dataset is divided into estimation and prediction subsets. The Box-Jenkins system identification method is used to built the model structure. The models are validated through analysis of the correlation of residuals by the Box-Ljung test and through calculation of the root mean squared error (RMSE)., Peer Reviewed, Postprint (published version)

This work develops and compares three different controllers for PEMFC systems in automotive applications. All the controllers have a cascade control structure, where a generator of setpoints sends references to the subsystems controllers with the objective to maximize operational efficiency. To develop the setpoints generators, two techniques are evaluated: off-line optimization and Model Predictive Control (MPC). With the first technique, the optimal setpoints are given by a map, obtained off-line, of the optimal steady state conditions and corresponding setpoints. With the second technique, the setpoints time profiles that maximize the efficiency in an incoming time horizon are continuously computed. The proposed MPC architecture divides the fast and slow dynamics in order to reduce the computational cost. Two different MPC solutions have been implemented to deal with this fast/slow dynamics separation. After the integration of the setpoints generators with the subsystems controllers, the different control systems are tested and compared using a dynamic detailed model of the automotive system in the INN-BALANCE project running under the New European Driving Cycle., Peer Reviewed, Postprint (published version)

Este proyecto trata de implementar una celda de combustible basada en una membrana intercambiadora de protones sobre una plataforma robótica ya existente. La idea de este proyecto es hacer un estudio para sustituir la alimentación actual de un robot con una celda de combustible, para así tener las ventajas que proporciona. Estas ventajas son un sistema más limpio, ya que necesita hidrógeno más el oxígeno del aire mismo para sólo dar como producto agua, también disminuye el tiempo de carga del robot ya que con las baterías este tiempo es mucho más extenso. Una celda de combustible hace que solo se necesite el tiempo de recarga del hidrógeno, que es menor que en baterías, además de poder hacer jornadas más largas sin tener que recargar. Además, se ha querido hacer un sistema modular, para que así se pueda quitar y poner este sistema según las necesidades, como también ser aprovechado para otros proyectos. En esta memoria se pueden encontrar explicaciones de los componentes básicos de este proyecto, que han sido la celda de combustible, la batería y las bombonas de hidrógeno. Como se ve, el sistema no sólo se basa en la celda de combustible, sino que se ha querido hacer un sistema híbrido con una batería, que se recarga con la propia celda de combustible, así no hay que parar a recargarla. Todo esto se ha calculado para dimensionarlo correctamente y así escoger los componentes con las capacidades correctas. Se ha hecho un análisis exhaustivo con datos obtenidos de unas pruebas que se hicieron con el robot al principio del proyecto. Se han planteado tres casos distintos con datos modificados para así poder estudiar distintas opciones, ya que por la situación actual no se han podido tener más pruebas con el robot. Dentro de estos tres casos, se han estudiado, además, tres casos de hibridación distintos, en función de cuánto trabajan la celda de combustible y la batería en cada momento. Así, se ha podido elegir uno de los casos más exigentes, para dimensionar correctament

Solid Oxide Elecyrolizers (SOEC) are electrochemical devises that produce hydrogen from water using the energy of an electric power source. SOEC operate at high temperatures (around 800ºC) and have efficiencies around 53% [1]. One of the most interesting scenarios of SOEC use is the storage of energy in hydrogen form when renewable power sources do not match the load. Because of this, it is important to study the dynamic behavior of SOEC systems in order to know their ability to adapt to changing power profiles. Different works describe SOEC models in the literature, as reviewed in [2], but time dependent models are scarse [3] and very few of the models are experimentally validated. This work presents a dy-namic model of a SOEC implemented in MATLAB Simulink and its match with experimental data. One important issue in SOEC stacks is hydrogen leak, which aggravates with ageing and is mostly caused by the high operating temperatures. The analysis of the experimental data of this work suggested hydrogen leak. Based on the SOEC thermal model, a methodology to quantify the flow of hydrogen that is leaked out is proposed and applied to the experimental system., Postprint (published version)

This work introduces our ongoing research in developing accurate models for predicting and analyzing Proton-Exchange Membrane Fuel Cells performance. An initial model, whose response is compared with experimental data is first implemented. The simulated (and theoretically expected) cell voltage deviates from real behavior when the operating conditions change. Then an improved model, aimed to better approximate instantaneous voltage response to changing operating conditions by including liquid water dynamics, is developed. The results show that the new model achieves a better approximation of the voltage profile. The model is validated through experiments on a real fuel cell test-bench., Peer Reviewed, Postprint (author's final draft)

The main objective of this work is to develop a software tool to perform an techno-economic feasibility analysis of cogeneration systems for electricity and heat production, based on fuel cell technology (FC-CHP). The software tool should provide useful information to the decision makers. Moreover, the developed software will be applied to specific case studies to obtain the main indicators of the economic viability of the system. A FC-CHP system is a technology with potential to change the current paradigm, which consists in obtaining electricity from the power grid and, separately, heat through gas boilers. The method developed in this study allows to carry out a viability analysis over a specific time horizon, based on technical and economic parameters, to size the FC-CHP system and to adapt the calculations to the market conditions of each case study. It is important to consider the market conditions, because the previous works found in the literature remark that the viability of the FC-CHP technology depends on specific factors that vary by country and region. Local economic factors include government policies to support new technologies of distributed generation, that is, generation of electricity at or near where it will be used. Another local factor is the difference in prices between natural gas and electricity ("spark spread"), and the expected evolution of these prices. From the environmental point of view, the composition of the country's power generation mix has influence on the emissions reduction using FC-CHP. The pattern of thermal and electrical energy demand of each specific case also influence, and the relative amount of each one (heat-to-power ratio). The method developed requires a source of energy consumption data, which can be real or simulated. Special attention has been paid to see the impact of few consumption data in the results. A correction has to be made in the results for those situations when only the aggregate monthly or weekly consu

Methane production through a solid oxide electrolyser with primary renewable source and carbon dioxide capture Renewable electric energy can be transformed into storable methane via electrolysis andsubsequent methanation. Power to Gas systems appear as a promising technology to ex-ploit the surplus energy from renewable power plants; different gases can be produced(e.g. methane or hydrogen).In this Master Thesis work, two different Power to Gas systems are modelled using Mat-lab Simulink: a Solid Oxide Electrolyser with aCO2-methanator and a Solid OxideCo-Electrolyser with aCO-methanator. This latter component can operate with an in-letH2/CO-ratio equale to 3 or larger. A ratio of 5 is also considered. TheCO2, comingfrom biogas produced in the Waste Water Treatment Plant ofEDAR Riu Secsituated inSabadell (Barcelona), is captured and processed in order to obtain methane. Additionally,according to the Master Thesis’ objectives, a photovoltaic power plant and aCO2stor-age are sized. An averaged power profile produced by a PV plant located in Barcelonais obtained with thePV*SOLprogramme. Therefore, the installation of a P2G systemallows to achieve two positive effects: firstly, theCO2is not released to the atmosphere.Secondly, theCO2is reused to produce methane without getting it, in a more pollutingway, from natural gas or coal.Nowadays not all the technologies analysed in this work are mature. Due to the com-plexity and partial lack of information simplified models and assumptions in operatingconditions have been employed.The main goal is to evaluate what is the most efficient Power to Gas choice in terms ofinstalled nominal power to exploit the entire amount of the carbon dioxide over one yearof operation. Furthemore the photovoltaic power plant is sized assuming operativity onlyduring the summer period; the differences with respect to yearly operation are illustratedin terms of required power and storage capacity.According to the results achieved in this work, the o, Outgoing

Proton Exchange Membrane Fuel Cells (PEMFC) are a promising technology for substitution of hydrocarbon powerdrives and battery based electrical supply systems. However, below-required durability is still an important factor that hinders its widespread use, thus, novel operating approaches are required to surpass this shortcoming. The present abstract presents a line of research directed towards the of analysis and definition of load profile characteristics in order to design controllers and operation strategies that optimize cell efficiency and durability. Degradation of the catalyst layer, commonly composed of platinum supported on carbon (Pt/C), mainly due to platinum loss by oxidation/dissolution and the resulting reduction of Electrochemical Active Surface Area (ECSA), is the main issue reducing the durability of PEMFC., Peer Reviewed, Postprint (author's final draft)

Dynamic models of PEM stacks are the basis to design controllers for appropriate performance, maximum efficiency and minimum degradation. Fluid dynamic models of different dimensions can be found in the literature; however, these models are rarely used to improve the control laws and strategies. This work presents a control oriented 1+1D model (distributed in the direction of the stack flow channels). The model is based on a similar model presented by M. Mangold [1], is implemented in MATLAB Simulink. The model is validated using experimental data of a Powercell stack., Peer Reviewed, Postprint (author's final draft)

Les piles d’hidrogen permeten obtenir energia elèctrica de forma eficient a partir d’hidrogen i poden ser unelement clau per a implementar sistemes energètics renovables, distribuïts i autònoms, facilitant una transició cap a un model energètic sostenible. Amb aquesta finalitat es crea el projecte REFER, un projecte integrat a la comunitat RIS3CAT-ENERGIA de Catalunya. L’objectiu principal del projecte és el desenvolupament de piles d’hidrogen que es puguin alimentar amb gas natural de la xarxa i proporcionar electricitat a edificis. Amb aquest objectiu s’elegeixen piles SOFC (d’alta temperatura) alimentades ambhidrogen mitjançant un reformador de gas metà amb vapor.Per a implementar el disseny de planta és necessari desenvolupar un model que simuli el seu funcionament i aquesta és la intenció d’aquest treball. Per a plantejar-ho, es divideix la planta en els elements que la componen i es modelen individualment per a la seva posterior unió. Aquest model hauria de poder preveure el funcionament de la planta en diferents condicions de treball i per tant permetre el seu disseny òptim i unsistema de control. Per areproduir la dinàmica dels elements de la planta s’utilitza el Simulink, una extensió del programa matemàtic Matlab que permet generar models matemàtics i interconnectar-los. Aquests models es basen en les lleis fisicoquímiques que regulen els components del sistema. Aquestes equacions i elseu comportament prové de diversos articles, alguns de piles d’hidrogen en general i d’altres específics sobre les SOFC.Com a resultat, s’ha aconseguit ajustar i adaptar el model de la pila SOFC als resultats experimentals de manera que es modela de forma prou exactala variació de voltatge amb la temperatura. Quantal reformador, el model creat és complet,però no s’assoleixen els fluxos d’hidrogen necessaris per a completar el disseny de planta.

Peer Reviewed, Postprint (author's final draft)

Proton exchange membrane (PEM) fuel cells, which use hydrogen as fuel, provide high power densities while operating at lower temperatures, reducing the cost of materials and maintenance. PEM fuel cells are suitable for a broad range of applications, such as stationary, combined heat and power (CHP), portable systems and automotive. Performance and degradation in PEM fuel cell-based systems is greatly influenced by the internal conditions of the fuel cell. In this doctoral thesis, an extensive study of modelling, observation and control strategies of a PEM fuel cell-based system is performed. The objective is to obtain advanced control solutions that aid to enhance the durability and improve the efficiency of fuel cells. These control solutions have to take into account the internal conditions of the fuel cell and use this information to operate the system under conditions that guarantee that the degradation rate of the fuel cell is not increased. At the same time, the controllers have to guarantee that the system achieves high efficiencies, considering the parasitic power consumption of the balance of plant (BoP) ancillaries. The observation and control solutions are evaluated using the New European Driving Cycle (NEDC) profile as a case study. The first part of the thesis introduces the motivation of the present work and the structure of the document. Additionally, the current state of the research regarding modelling, state observers and control strategies for PEM fuel cell-based systems are studied in detail. After the study of the state of the art, the objectives of this doctoral work are presented. The second part of the thesis is focused on the development, implementation and study in a simulation environment of a PEM fuel cell-based system model. The model considers spatial derivatives for the fuel cell in order to represent the internal dynamic behaviour, which affects the efficiency and degradation rate of the system. In this thesis, a special attention is, Las pilas de combustible de membrana de intercambio protónico (PEM), las cuales utilizan hidrógeno como combustible, proporcionan altas densidades de potencia operando a bajas temperaturas, reduciéndose el coste de los materiales y el mantenimiento. Las pilas de combustible de tipo PEM son apropiadas para un amplio rango de aplicaciones, tales como estacionarias, de ciclo combinado (CHP), sistemas portátiles y automoción. El rendimiento y la degradación en sistemas basados en pilas de combustible de tipo PEM están importantemente influenciados por las condiciones internas. En la presente tesis doctoral, se realiza un extenso estudio de modelado y estrategias de observación y control en un sistema basado en pila de combustible de tipo PEM. El objetivo es obtener soluciones avanzadas de control que ayuden en la mejora de la durabilidad e incrementar la eficiencia de las pilas de combustible. Dichas soluciones de control tienen que tener en cuenta las condiciones internas de la pila de combustible, y utilizar esta información para operar el sistema bajo condiciones que garanticen que la degradación del sistema no se incrementa. Al mismo tiempo, los controladores deben garantizar que el sistema alcanza altas eficiencias, considerando las pérdidas por consumos parasíticos de los auxiliares del balance de la planta (BoP). Las soluciones de observación y control son evaluadas utilizando el perfil de conducción New European Driving Cycle (NEDC). La primera parte de la tesis introduce la motivación tras el presente trabajo y la estructura del documento. Se estudia en detalle el estado actual de la investigación referente a modelado, observadores de estados y estrategias de control para sistemas basados en pilas de combustible. Tras este estudio del estado del arte, se presentan los objetivos de la tesis. La segunda parte de la tesis está enfocada en el desarrollo, implementación y estudio en un entorno de simulación de un modelo de sistema basado en pila de combustible de ti, Postprint (published version)

The highlyincreasingenergydemandandreductionofavailablefossilenergysourceshave made it important to developa new technique for energy storage,hydrogen being a good alternative for the future. That is there as on why with in this project, The storage of hydrogen as an adsorbed element in metal hydride bottles has been studied, Morespecificallyhydrogen desorption anddischarge. Tothisend,atwodimensionalaxisymmetricmodelisdevelopedtostudythehydrogen desorption reactionandresultantmass and heattransportphenomenainsideametalhydride canister. Moreover,theworkhasalsobeenfocusedonexperimentaltestsperformedonan in-house fabricatedsetupusingdifferent heating scenarios. It isimportanttomentionthatthestudiedsystemhasalotofunknowns,asthemetalinside the bottle, aswellastheinternalcanisterstructure andmorphologyarenotknown.Thatisthe reason whyanextensive studyon the effects ofthemetalpropertiesondesorptionperformance is carriedoutthroughnon-destructivetesting(NDT). Thenumericalmodelresultsareexplained in detailandcomparedwithexperimentaldataaswell,obtainingagoodagreement. Finally,theresultsobtainedcannotonlybeusedtoselectmetalhydridematerialsbutalso to evaluatethedegradation ofthe canisters intermsoftotalhydrogenstoragecapacity.

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., The aim of this research is to develop and test in a simulation environment an advanced model-based control solution for a proton exchange membrane fuel cell (PEMFC) system. A nonlinear model-predictive control (NMPC) strategy is proposed to maximize the active catalytic surface area at the cathode catalyst layer to increase the available reaction area of the stack and to avoid starvation at the catalyst sites. The PEMFC stack model includes a spatial discretization that permits the control strategy to take into account the internal conditions of the system. These internal states are estimated and fed to the NMPC via a nonlinear distributed parameters observer. The air-fed cathode of the PEMFC simulation model includes a two-phase water model for better representation of the stack voltage. The stack temperature is regulated through the use of an active cooling system. The control strategy is evaluated in an automotive application using a driving cycle based on the New European Driving Cycle profile as the case study., Peer Reviewed, Postprint (author's final draft)

A two-dimensional axisymmetric model is developed to study the hydrogen absorption reaction and resultant mass and heat transport phenomena inside a metal hydride canister. The model is compared against published literature and experimental data. Experimental tests are performed on an in-house fabricated setup using different cooling scenarios. An extensive study on the effects of the metal properties on charging performance is carried out through non-destructive testing (NDT). Results show that the properties that most influence the charging performance are: absorption rate constant (Ca), activation energy (Ea) and thermal conductivity (km). A Higher porosity (e) reduces charging time and amount of hydrogen stored while a higher cooling level produces a faster charging process. These results can be used to select metal hydride materials but also to estimate the metal hydride internal state and the process can be used for future evaluation of metal hydride degradation., Postprint (author's final draft)

In the present work, a dynamic lumped parameter model of the electrochemical and thermal behavior of a Solid Oxide Fuel Cell (SOFC) has been developed. The model is implemented in the MATLAB-Simulink visual programming software. The model was calibrated using experimental data. A strategy is proposed for the thermal management of the stack and a controller is designed to keep the operating temperature of the system constant. This implemented strategy and controller is evaluated through simulation., Postprint (author's final draft)

© . 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 Reviewed, Postprint (author's final draft)

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 Reviewed, Postprint (author's final draft)

© . This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, This paper compares two Nonlinear Distributed Parameter Observers (NDPO) for the observation of a Proton Exchange Membrane Fuel Cell (PEMFC). Both NDPOs are based on the discretisation of distributed parameters models and they are used to estimate the state profile of gas concentrations in the anode and cathode gas channels of the PEMFC, giving detailed information about the internal conditions of the system. The reaction and water transport flow rates from the membrane to the channels are uncertainties of the observation problem and they are estimated throughout all the length of the PEMFC without the use of additional sensors. The first observation approach is a Nonlinear Disturbance Observer (NDOB) for the estimation of the disturbances in the NDPO. In the second approach, a novel implementation of a High-Order Sliding-Mode (HOSM) observer is developed to estimate the true value of the states as well as the reaction terms. The proposed observers are tested and compared through a simulation example at different operating points and their performance and robustness is analysed over a given case study, the New European Driving Cycle., Peer Reviewed, Postprint (author's final draft)

© 20xx IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., In this paper a methodology for the estimation of the Electrochemically active Surface Area (ECSA) of a Proton Exchange Membrane Fuel Cell (PEMFC) is developed. Specifically, the ECSA in the Cathode Catalyst Layer (CCL) is estimated, which makes it possible to quantify the amount of active platinum (Pt) in the CCL. In order to estimate the ECSA, the internal conditions of the PEMFC have to be known. A model-based observer for the distributed parameter dynamics is designed. From the observation of the distributed states, the ECSA can be estimated as well. 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 CCL. The results of the methodology are discussed in a simulation environment using the New European Driving Cycle (NEDC) as a case study., Peer Reviewed, Postprint (author's final draft)

This paper presents the development of a nonlinear state observer to estimate the different gas species concentration profiles in a Proton Exchange Membrane Fuel Cell energy system. The selection of the estimated states follows functionality and fuel cell performance criteria. The implementation is based on the finite element discretisation of a fuel cell distributed parameter model. Forward and backwards discretisation of the partial derivative equations is performed to take advantage of the boundary conditions of the problem and also to apply lumped systems theory in the synthesis procedure of the observer. A second-order sliding-mode super-twisting corrective input action is implemented to reduce the estimation error to zero in a finite amount of time. The sliding-mode control approach grants a suitable corrective action without incrementing the model-dependency of the observer. Simulation results are presented to show the performance of the proposed observer of the fuel cell internal states and to extract conclusions for future research work., Peer Reviewed, Postprint (author's final draft)

In this paper, a nonlinear distributed parameter observer (NDOP) is developed for the estimation of the internal condi-tions of a proton exchange membrane fuel cell (PEMFC). In particular, the estimation of the internal concentration values for different gas species is studied. A novel high order sliding mode (HOSM) estimation technique, based on a distributed parameter model of a PEMFC is developed to reconstruct the internal variables. The observer includes the estimation of the reaction and water transport terms, which are considered as disturbances of the PEMFC estimation model. Since the approach is based on a distributed parameter model representation of the PEMFC, the observer is capable of reconstruct the full internal profile of the estimated variables. The performance and robustness of the proposed observation technique is tested through a simulation example around different operation points., Peer Reviewed, Postprint (author's final draft)

El gran augment en la demanda energètica i la reducció de les fonts d’energia fòssil disponibles han fet que sigui important desenvolupar una nova tècnica per a emmagatzemar energia, sent l’hidrogen una bona alternativa pel futur. Aquesta és la raó per la qual en aquest projecte s’ha estudiat l’emmagatzematge d’hidrogen com a element absorbit dins d’ampolles d’hidrur metàl·lic. Amb aquesta finalitat s’ha desenvolupat un model tridimensional del procés de càrrega en el recipient d’hidrur metàl·lic que és capaç de representar fidelment el comportament del sistema. Aquest model matemàtic ha sigut implementat en un programa d’elements finits que permet obtenir resultats de les variables de càrrega per diferents escenaris. A més a més, el treball també ha estat centrat en assajos experimentals realitzats sobre un muntatge de sensors i el seu sistema d’adquisició de dades, dissenyats i configurats per a aquest propòsit. Aquests experiments s’han executat per les situacions de càrrega i descàrrega en diferents circumstàncies, per exemple canviant les condicions exteriors. Els resultats de la simulació i les dades experimentals s’han comparat i contrastat per a validar experimentalment la simulació numèrica. Finalment també s’ha presentat una proposta per un estimador de l’estat de càrrega de l’hidrur metàl·lic basada en el treball realitzat.

In this paper a nonlinear state observer based on a distributed parameter model is proposed for a proton exchange membrane fuel cell (PEMFC). The estimation technique is implemented using a model-based nonlinear observer with a nonlinear disturbance observer in parallel. To implement the model, a finite element discretisation is performed to take advantage of the boundary conditions of the problem and also to apply lumped systems theory in the observer synthesis procedure. By means of this double observation technique it is possible to reconstruct the gases concentrations internal states in the gas channels of the PEMFC in the presence of disturbances. The reaction rates and water transport terms that cross the membrane are considered as unknown unmatched disturbances of the model, henceforth the implementation of a disturbance observer to estimate them. Simulation results of the proposed solution are provided and discussed., Peer Reviewed, Postprint (author’s final draft)