728 research outputs found

    Multivariable robust control of a simulated hybrid solid oxide fuel cell gas turbine plant

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    This work presents a systematic approach to the multivariable robust control of a hybrid fuel cell gas turbine plant. The hybrid configuration under investigation built by the National Energy Technology Laboratory comprises a physical simulation of a 300kW fuel cell coupled to a 120kW auxiliary power unit single spool gas turbine. The public facility provides for the testing and simulation of different fuel cell models that in turn help identify the key difficulties encountered in the transient operation of such systems. An empirical model of the built facility comprising a simulated fuel cell cathode volume and balance of plant components is derived via frequency response data. Through the modulation of various airflow bypass valves within the hybrid configuration, Bode plots are used to derive key input/output interactions in transfer function format. A multivariate system is then built from individual transfer functions, creating a matrix that serves as the nominal plant in an Hinfinity robust control algorithm. The controller\u27s main objective is to track and maintain hybrid operational constraints in the fuel cell\u27s cathode airflow, and the turbo machinery states of temperature and speed, under transient disturbances. This algorithm is then tested on a Simulink/MatLab platform for various perturbations of load and fuel cell heat effluence.;As a complementary tool to the aforementioned empirical plant, a nonlinear analytical model faithful to the existing process and instrumentation arrangement is evaluated and designed in the Simulink environment. This parallel task intends to serve as a building block to scalable hybrid configurations that might require a more detailed nonlinear representation for a wide variety of controller schemes and hardware implementations

    Non-adiabatic capillary tubes in high efficiency household refrigerator: an experimental study

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    El tubo capilar con intercambio de calor líquido-succión (CT-LSHX) es un componente ampliamente utilizado en refrigeradores domésticos. Trabajos recientes han indicado que la entrada del tubo capilar era bifásica, aunque condiciones subenfriadas estaban medidas a la salida del condensador. El objetivo de esta tesis doctoral es examinar las condiciones reales a la entrada del tubo capilar de un refrigerador doméstico mediante el uso de un banco de pruebas innovador. Se instalaron tubos transparentes a la salida del condensador y a la entrada del tubo capilar con el fin de visualizar el flujo. La campaña de visualización experimental revela que el flujo a la entrada del tubo capilar era bifásico a pesar de la medición de un cierto subenfriamiento, independientemente de la posición del filtro instalado a la entrada del capilar (horizontal o vertical), la dirección del flujo (hacia arriba o hacia abajo) y la carga de refrigerante. Este estudio demuestra también que el filtro no estaba actuando como un acumulador ya que el nivel de líquido del capilar siempre siguió la entrada del tubo capilar, independientemente de la longitud del tubo capilar dentro del filtro. Se plantearon dos hipótesis para explicar el fenómeno: una condición de no equilibrio del refrigerante y/o un desequilibrio entre el caudal másico del compresor y del capilar, es decir, el sistema estaría equipado con un capilar no bastante restrictivo en comparación con las necesidades del compresor. El condensador original refrigerante-aire fue reemplazado por un condensador refrigerante-agua para evaluar, a partir del balance de calor en el condensador de agua, las condiciones del refrigerante a la salida del condensador y, por lo tanto, a la entrada del tubo capilar. Las mediciones indican un flujo bifásico no equilibrado compuesto de vapor y líquido subenfriados a la entrada del tubo capilar. Para verificar si la presencia de flujo bifásico se debía a un desequilibrio entre el caudal másico del compresor y del capilar, el diseño del banco de prueba se modificó utilizando un diámetro de tubo capilar más pequeño y aumentando la velocidad del compresor. Con esta nueva configuración, se alcanzó a llenar de líquido el filtro y, por lo tanto, tener condiciones exclusivamente líquidas a la entrada del tubo capilar. Se realizó una comparación de prestaciones entre un flujo bifásico y un flujo únicamente líquido a la entrada del capilar. Los resultados revelan que el COP fue mayor cuando la entrada del capilar era sólo líquida.El tub capil·lar amb intercanvi de calor líquid-succió (CT-LSHX) és un component àmpliament utilitzat en refrigeradors domèstics. Treballs recents han indicat que l'entrada del tub capil·lar era bifàsica, encara que condicions sub-refredades estaven mesurades a l'eixida del condensador. L'objectiu d'aquesta tesi doctoral és examinar les condicions reals a l'entrada del tub capil·lar d'un refrigerador domèstic mitjançant l'ús d'un banc de proves innovador. Es van instal·lar tubs transparents a l'eixida del condensador i a l'entrada del tub capil·lar amb la finalitat de visualitzar el flux. La campanya de visualització experimental revela que el flux a l'entrada del tub capil·lar era bifàsic malgrat el mesurament d'un cert sub-refredament, independentment de la posició del filtre instal·lat a l'entrada del capil·lar (horitzontal o vertical), la direcció del flux (cap amunt o cap avall) i la càrrega de refrigerant. Aquest estudi demostra també que el filtre no estava actuant com un acumulador ja que el nivell de líquid del capil·lar sempre va seguir l'entrada del tub capil·lar, independentment de la longitud del tub capil·lar dins del filtre. Es van plantejar dues hipòtesis per a explicar el fenomen: una condició de no equilibri del refrigerant i/o un desequilibri entre el cabal màssic del compressor i del capil·lar, és a dir, el sistema estaria equipat amb un capil·lar no bastant restrictiu en comparació amb les necessitats del compressor. El condensador original refrigerant-aire va ser reemplaçat per un condensador refrigerant-aigua per a avaluar, a partir del balanç de calor en el condensador d'aigua, les condicions del refrigerant a l'eixida del condensador i, per tant, a l'entrada del tub capil·lar. Els mesuraments indiquen un flux bifàsic no equilibrat compost de vapor i líquid sub-refredats a l'entrada del tub capil·lar. Per a verificar si la presència de flux bifàsic es devia a un desequilibri entre el cabal màssic del compressor i del capil·lar, el disseny del banc de prova es va modificar utilitzant un diàmetre de tub capil·lar més xicotet i augmentant la velocitat del compressor. Amb aquesta nova configuració, es va aconseguir omplir de líquid el filtre i, per tant, tindre condicions exclusivament líquides a l'entrada del tub capil·lar. Es va realitzar una comparació de prestacions entre un flux bifàsic i un flux únicament líquid a l'entrada del capil·lar. Els resultats revelen que el COP va ser major quan l'entrada del capil·lar era només líquida.Capillary tube with liquid-to-suction heat exchanger (CT-LSHX) is a component widely used in household refrigerators. Recent works have indicated that even when measuring subcooled conditions at the condenser outlet, the actual capillary tube inlet is two phase-flow. The aim of this PhD thesis is to examine the actual conditions at the capillary tube inlet of a household refrigerator by using an innovative test bench. Transparent tubes were set up at the condenser outlet and capillary tube inlet. The experimental visualisation campaign reveals that the capillary tube inlet was two-phase flow despite the measurement of a certain subcooling, regardless of the filter position (horizontal or vertical), flow direction (upward or downward) and refrigerant charge. This study also demonstrates that the filter was not acting as an accumulator since the liquid level of the capillary always followed the capillary tube entrance, regardless of the capillary tube length inside the filter. Two hypotheses were then posed to explain the phenomenon: a non-equilibrium condition of the refrigerant and/or an unbalanced matching between compressor and capillary tube, that is, the system would be equipped with a capillary tube with a notably large expansion capacity compared to the needs of the compressor. The original refrigerant-to-air condenser was replaced by a refrigerant-to-water condenser to assess, from the heat balance at the water condenser, the refrigerant conditions at the condenser outlet and therefore, at the capillary tube inlet. Measurements indicate a non-equilibrium two-phase flow composed of subcooled vapour and liquid at the capillary tube inlet. To verify if the presence of two-phase flow was due to unbalanced matching between the capillary tube and compressor, the test bench design was modified by using a smaller capillary tube diameter and increasing compressor speed. Fully liquid conditions at the capillary tube inlet were reached with this new configuration. A performance analysis comparison between a capillary tube inlet composed of vapour and liquid and a capillary tube inlet composed of only liquid was also performed. Results reveal that COP were higher in cases of fully liquid conditions at the capillary tube inlet.Bardoulet, LV. (2018). Non-adiabatic capillary tubes in high efficiency household refrigerator: an experimental study [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/113170TESI

    A Methodology Towards Comprehensive Evaluation of Shape Memory Alloy Actuators for Prosthetic Finger Design

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    Presently, DC motors are the actuator of choice within intelligent upper limb prostheses. However, the weight and dimensions associated with suitable DC motors are not always compatible with the geometric restrictions of a prosthetic hand; reducing available degrees of freedom and ultimately rendering the prosthesis uncomfortable for the end-user. As a result, the search is on-going to find a more appropriate actuation solution that is lightweight, noiseless, strong and cheap. Shape memory alloy (SMA) actuators offer the potential to meet these requirements. To date, no viable upper limb prosthesis using SMA actuators has been developed. The primary reasons lie in low force generation as a result of unsuitable actuator designs, and significant difficulties in control owing to the highly nonlinear response of SMAs when subjected to joule heating. This work presents a novel and comprehensive methodology to facilitate evaluation of SMA bundle actuators for prosthetic finger design. SMA bundle actuators feature multiple SMA wires in parallel. This allows for increased force generation without compromising on dynamic performance. The SMA bundle actuator is tasked with reproducing the typical forces and contractions associated with the human finger in a prosthetic finger design, whilst maintaining a high degree of energy efficiency. A novel approach to SMA control is employed, whereby an adaptive controller is developed and tuned using the underlying thermo-mechanical principles of operation of SMA wires. A mathematical simulation of the kinematics and dynamics of motion provides a platform for designing, optimizing and evaluating suitable SMA bundle actuators offline. This significantly reduces the time and cost involved in implementing an appropriate actuation solution. Experimental results show iii that the performance of SMA bundle actuators is favourable for prosthesis applications. Phalangeal tip forces are shown to improve significantly through bundling of SMA wire actuators, while dynamic performance is maintained owing to the design and implementation of the selected control strategy. The work is intended to serve as a roadmap for fellow researchers seeking to design, implement and control SMA bundle actuators in a prosthesis design. Furthermore, the methodology can also be adopted to serve as a guide in the evaluation of other non-conventional actuation technologies in alternative applications

    Dynamic Modeling, Predictive Control and Optimization of a Rapid Pressure Swing Adsorption System

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    Rapid Pressure Swing Adsorption (RPSA) is a gas separation technology with an important commercial application for Medical Oxygen Concentrators (MOCs). MOCs use RPSA technology to produce high purity oxygen (O2) from ambient air, and provide medical oxygen therapy to Chronic Obstructive Pulmonary Disease (COPD) patients. COPD is a lung disease which prevents O2 from entering a patient\u27s blood, and reduces the blood oxygen level. The standard therapy for COPD is to provide the patient with high purity (~90%) O2. MOCs have become more popular than traditional O2 gas cylinders due to their improved safety, and smaller device size and weight. The MOC market is growing rapidly and was expected to grow from 358millionin2011to358 million in 2011 to 1.8 billion in 2017. Recently, a novel, single-bed MOC design was developed and tested to further reduce the size and weight of the device, and provide a continuous supply of O2 to the patient. This single-bed design uses a complex RPSA cyclic process with many nonlinear effects. Flow reversals, discrete valve switching, nonlinear adsorption effects, and complex fluid dynamics all make operating the RPSA system very challenging. Feedback control is necessary in a final commercial product to ensure the device operates reliably, but feedback control of PSA systems is not well studied in the current literature.In this work, a study of dynamic modeling, predictive control and optimization of this single-bed RPSA device is presented. A detailed, nonlinear plant model of the RPSA device is used to study the dynamics of the system as well as design a Model Predictive Controller (MPC) for the RPSA system. The plant model is a fully coupled, nonlinear set of Partial and Ordinary Differential Equations (PDEs and ODEs) which act as a representation of reality when design and evaluating the MPC. A sub-space model identification technique using Pseudo-Random Binary Sequence (PRBS) input signals generate a linear model which reduces the computational cost of MPC, and allows the algorithm to be implemented as an embedded controller for the RPSA device. The multivariable MPC independently manipulates the RPSA cycle step durations to control both the product composition and pressure. This MPC strategy was designed and tested in simulation before being implemented on a lab-scale device.The MPC is implemented onto a lab-scale MOC prototype using Raspberry Pi hardware, and evaluated using several MOC-relevant disturbance scenarios. The MPC is also expanded using piece-wise linear modeling to improve the performance of an RPSA device for other concentrated O2 applications. The embedded MPC features a convex quadratic optimization problem which is solved in real time using online output measurements. Additional hardware in the embedded controller operates the RPSA cycle and implements control actions supplied by the MPC.Design and optimization of RPSA systems remains an active area of research, and many PSA models have been used to optimize RPSA cycles in simulation. In this work, a model-free steady state optimization approach using the embedded hardware is presented which does not require a detailed process model, and uses experimental data and a nonlinear solver to optimize the RPSA operation given various objectives

    Design, construction and commissioning of the Thermal Screen Control System for the CMS Tracker detector at CERN

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    The CERN (European Organization for Nuclear Research) laboratory is currently building the Large Hadron Collider (LHC). Four international collaborations have designed (and are now constructing) detectors able to exploit the physics potential of this collider. Among them is the Compact Muon Solenoid (CMS), a general purpose detector optimized for the search of Higgs boson and for physics beyond the Standard Model of fundamental interactions between elementary particles. This thesis presents, in particular, the design, construction, commissioning and test of the control system for a screen that provides a thermal separation between the Tracker and ECAL (Electromagnetic CALorimeter) detector of CMS (Compact Muon Solenoid experiment). Chapter 1 introduces the new challenges posed by these installations and deals, more in detail, with the Tracker detector of CMS. The size of current experiments for high energy physics is comparable to that of a small industrial plant: therefore, the techniques used for controls and regulations, although highly customized, must adopt Commercial Off The Shelf (COTS) hardare and software. The âワslow controlâ systems for the experiments at CERN make extensive use of PLCs (Programmable Logic Controllers) and SCADA (Supervisory Control and Data Acquisition) to provide safety levels (namely interlocks), regulations, remote control of high and low voltages distributions, as well as archiving and trending facilities. The system described in this thesis must follow the same philosophy and, at the same time, comply with international engineering standards. While the interlocks applications belong straightforwardly to the category of DES (Discrete Event System), and are therefore treated with a Finite State Machine approach, other controls are more strictly related to the regulation problem. Chapter 2 will focus on various aspects of modern process control and on the tools used to design the control system for the thermal screen: the principles upon which the controller is designed and tuned, and the model validated, including the Multiple Input-Multiple Output (MIMO) problematics are explained. The thermal screen itself, the constraints and the basis of its functioning are described in Chapter 3, where the thermodynamical design is discussed as well. For the LHC experiments, the aim of a control system is also to provide a well defined SIL (Safety Interlock Level) to keep the system in a safe condition; yet, in this case, it is necessary to regulate the temperature of the system within certain values and respect the constraints arising from the specific needs of the above mentioned subsystems. The most natural choice for a PLC-based controller is a PID (Proportional Integral Derivative) controller. This kind of controller is widely used in many industrial process, from batch production in the pharmaceutics or automotive field to chemical plants, distillation columns and, in general, wherever a reliable and robust control is needed. In order to design and tune PID controllers, many techniques are in use; the approach followed in this thesis is that of black-box modeling: the system is modeled in the time domain, a transfer function is inferred and a controller is designed. Then, a system identification procedure allows for a more thorough study and validation of the model, and for the controller tuning. Project of the thermal screen control including system modeling, controller design and MIMO implementation issues are entirely covered in Chapter 4. A systems engineering methodology has been followed all along to adequately manage and document every phase of the project, complying with time and budget constraints. A risk analysis has been performed, using Layer of Protection Analysis (LOPA) and Hazard and Operability Studies (HAZOP), to understand the level of protection assured by the thermal screen and its control components. Tests planned and then performed to validate the model and for quality assurance purposes are described in Chapter 5. A climatic chamber has been designed and built at CERN, where the real operating conditions of the thermal screen are simulated. Detailed test procedures have been defined, following IEEE standards, in order to completely check every single thermal screen panel. This installation allows for a comparison of different controller tuning approaches, including IAE minimization, Skogestad tuning rules, Internal Model Control (IMC), and a technique based upon the MatLab Optimization toolbox. This installation is also used for system identification purposes and for the acceptance tests of every thermal screen panel (allowing for both electrical and hydraulic checks). Also, tests have been performed on the West Hall CERN experimental area , where a full control system has been set up, for interlock high- and low- voltage lines. The interlock system operating procedures and behaviour have been validated during real operating conditions of the detector esposed to a particle beam. The satisfactory results of tests take the project to full completion, allowing the plan to reach the âワexitâ stage, when the thermal screen is ready to be installed in the Tracker and ready to be operational

    Development of an Installation to Emulate Altitude, Ambient Temperature, and Ambient Humidity on Thermal Engines. Application to the Study of the Impact over E6 Engine Performance

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    [ES] Las normativas cada vez más restrictivas sobre las emisiones contaminantes de los vehículos de motor impuestas por la Unión Europea han obligado a los fabricantes de equipos originales (OEM) a proporcionar a los centros de investigación herramientas e instalaciones que pueden reproducir de forma precisa y repetida diferentes condiciones atmosféricas durante las primeras etapas del desarrollo del motor. En la actualidad la legislación europea incluye pruebas de emisiones reales en conducción (RDE) en diferentes condiciones atmosféricas, con altitudes de hasta 1300 metros sobre el nivel del mar y temperaturas que alcanzan los -7 ºC. Esto se ha hecho típicamente utilizando cámaras climáticas y altimétricas que permiten la reproducción de las condiciones atmosféricas en toda la celda de prueba, y más recientemente conectando a motor simuladores de altitud acoplados con unidades de tratamiento de aire (AHU). En esta Tesis Doctoral, se presenta la mejora del simulador de altitud comercializado por la empresa HORIBA denominado MEDAS, utilizando procedimientos tanto inductivos como deductivos, con el objetivo de ampliar el rango de prestaciones de la instalación, así como mejorar la precisión del control de la presión del aire comburente y reducir el consumo energético global. Además, durante esta fase, se lleva a cabo el desarrollo de un modelo 1D del simulador de altitud, con el que es posible obtener resultados precisos sobre el desempeño de la instalación para diferentes condiciones de contorno, como puede ser el punto operativo del motor, la presión de la sala o la temperatura del agua de refrigeración. A continuación, se han desarrollado dos nuevos equipos: el Módulo de Temperatura del MEDAS (MTM) y el Módulo de Humedad del MEDAS (MHM); mejorando las estrategias de control y algunos componentes clave (por ejemplo, la columna de agua de burbujas) para controlar con precisión la temperatura y la humedad del aire de combustión. Estos dos junto con el MEDAS crean un simulador de atmósfera completo, que permite el control independiente de las tres variables psicrométricas del aire de combustión del motor: presión, temperatura y humedad. Por último, el simulador de atmósfera desarrollado se utiliza para estudiar el efecto que las tres variables psicométricas del aire ambiente tienen sobre el rendimiento y las emisiones contaminantes de un motor Diesel Euro 6 turboalimentado, demostrando el gran efecto que tiene la humedad ambiental sobre las emisiones contaminantes de los motores Diesel y la necesidad de considerar este parámetro en las estrategias de calibración. Algunos resultados obtenidos podrían ser la reducción de potencia que el motor sufre al operar en condiciones de altitud, los cambios que la temperatura ambiente causa en el punto de operación del turbo grupo o como las emisiones de NOx se reducen cuando la humedad ambiente aumenta.[CA] Les normatives cada vegada més restrictives sobre les emissions contaminants dels vehicles de motor imposades per la Unió Europea han obligat als fabricants d'equips originals (OEM) a proporcionar als centres d'investigació eines i instal·lacions que poden reproduir de manera precisa i repetida diferents condicions atmosfèriques durant les primeres etapes del desenvolupament del motor. En l'actualitat la legislació europea inclou proves d'emissions reals en conducció (RDE) en diferents condicions atmosfèriques, amb altituds de fins a 1300 metres sobre el nivell de la mar i temperatures que aconsegueixen els -7 °C. Això s'ha fet típicament utilitzant cambres climàtiques i altimètriques que permeten la reproducció de les condicions atmosfèriques en tota la cel·la de prova, i més recentment connectant a motor simuladors d'altitud acoblats amb unitats de tractament d'aire (AHU). En aquesta Tesi Doctoral, es presenta la millora del simulador d'altitud comercialitzat per l'empresa HORIBA denominat MEDAS, utilitzant procediments tant inductius com deductius, amb l'objectiu d'ampliar el rang de prestacions de la instal·lació així com millorar la precisió del control de pressió de l'aire de combustió i reduir el consum energètic global. A més, durant aquesta fase, es du a terme el desenvolupament d'un model 1D del simulador d'altitud, amb el qual és possible obtindre resultats precisos sobre l'acompliment de la instal·lació per a diferents condicions de contorn, com pot ser el punt d'operació del motor, l'altitud d'instal·lació o la temperatura de l'aigua de refrigeració. A continuació, s'han desenvolupat dos nous equips: el Mòdul de Temperatura del MEDAS (MTM) i el Mòdul d'Humitat del MEDAS (MHM); millorant les estratègies de control i alguns components clau (per exemple, la columna d'aigua de bambolles) per a controlar amb precisió la temperatura i la humitat de l'aire de combustió. Aquests dos juntament amb el MEDAS creen un simulador d'atmosfera complet, que permet el control independent de les tres variables psicromètriques de l'aire de combustió del motor: pressió, temperatura i humitat. Finalment, el simulador d'atmosfera desenvolupat s'utilitza per a estudiar l'efecte que les tres variables psicomètriques de l'aire ambient tenen sobre el rendiment i les emissions contaminants d'un motor Dièsel Euro 6 *turboalimentado, demostrant el gran efecte que té la humitat ambiental sobre les emissions contaminants dels motors Dièsel i la necessitat de considerar aquest paràmetre en les estratègies de calibratge. Alguns resultats obtinguts podrien ser la reducció de potència que el motor pateix en operar en condicions d'altitud, els canvis que la temperatura ambient causa en el punt d'operació del turbo grup o com les emissions de NOx es redueixen quan la humitat ambiente augmenta.[EN] Increasingly restrictive regulations on pollutant emissions for motor vehicles imposed by the European Union have forced original equipment manufacturers (OEMs) to provide research centers with tools and facilities that can accurately and repeatedly reproduce different atmospheric conditions during the early stages of engine development. Nowadays, the European legislation includes real driving emissions (RDE) tests at different atmospheric conditions, with altitudes up to 1300 meters above sea level and temperatures reaching -7 ºC. This has been done typically using altimetric and climatic chambers, which allow the reproduction of the atmospheric conditions in the whole test cell. More recently, connecting to the engine altitude simulators coupled with air handling units (AHU). In this Ph.D. Thesis, the improvement of the altitude simulator commercialized by the company HORIBA called MEDAS, carried out by inductive and deductive procedures, is presented to extend the installation's performance range, improve the combustion air pressure control accuracy, and reduce the installation global energy consumption. Furthermore, during this phase, the development of a 1D model of the altitude simulator is carried out, with which it is possible to obtain accurate results about the performance of the installation for different boundary conditions such as the engine operation point, the room pressure, or the cooling water temperature. Following, two new pieces of equipment have been developed: MEDAS Temperature Module (MTM) and MEDAS Humidity Module (MHM), improving the control strategies and some key components (i.e., the bubbles water-column) to increase the accuracy of the combustion air temperature and humidity control. Together with the MEDAS, these two create a complete atmosphere simulator, which allows the independent control of the three psychrometric variables of the engine combustion air: pressure, temperature, and humidity. Lastly, the atmosphere simulator developed is used to study the effect that the three psychometric variables of the ambient air have on the performance and the pollutant emissions of a Euro 6 turbocharged diesel engine, proving the significant effect that the ambient humidity has on the diesel engines pollutant emissions and the necessity of considering this parameter in the calibration strategies. Some results could be the reduction in power that the engine suffers when operating in altitude conditions, the changes that the ambient temperature causes at the turbocharger operative point, or the decrease in NOx emissions that happen when the ambient humidity increases.Tabet Aleixandre, R. (2022). Development of an Installation to Emulate Altitude, Ambient Temperature, and Ambient Humidity on Thermal Engines. Application to the Study of the Impact over E6 Engine Performance [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/183753TESI

    The design and evaluation of a PLC-based model predictive controller for application in industrial food processes

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    Model Predictive Control (MPC) is a viable control strategy for industrial processes that display relatively large variations in the process variable, have complex process variable interactions, or display a large amount of process deadtime. The objective of using MPC in manufacturing is to reduce overall process variability, the result being an increase in process accuracy, precision and efficiency. This study focused on the implementation of model predictive control techniques on an industrial sugar cooking process. The goal was to implement a successful MPC solution directly on a programmable logic controller (PLC) rather than on a personal computer (PC). Although there are many commercially available MPC controllers for implementation on a stand-alone PC, to date there are no control packages for realizing model-based control techniques directly on the ubiquitous PLC. This study implemented and evaluated three PC-based, commercial MPC technologies for the sugar cooking process, and a new model state feedback (MSF) MPC implementation directly on Rockwell Automation\u27s Allen-Bradley ControlLogix ® PLC. A standard proportional-integral-derivative (PID) control implementation was used as a baseline for comparing the MPC strategies. There were three main areas on which the overall comparative analysis focused. These comparison areas were the dynamic response of each strategy at startup, including both temperature rise time and overshoot, and the steady-state disturbance rejection capabilities of each strategy. The test results showed that the MPC strategies controlled the sugar cooking process better than the traditional PID control method in regards to temperature rise time, temperature overshoot, and disturbance rejection based on feed rate disturbances. It was seen that the differences between the various MPC strategies was not significant relative to temperature overshoot and disturbance rejection. The PLC-based MPC strategy was comparable, but not superior, to the PC-based commercial MPC applications. However, this strategy has several benefits such as requiring no external hardware, software, and communications protocols, which may result in a less expensive implementation than the commercial MPC strategies. The PLC-based strategy is also easier and cheaper to maintain because it is developed on the existing, well-known control platform with existing tools
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