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Dissertations / Theses on the topic 'Control of distributed parameter systems'
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1
Rubio, Diana. "Distributed Parameter Control of Thermal Fluids." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30330.
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We consider the problem of controlling a thermal convection flow by feedback. The system is governed by the Boussinesq approximation of the coupled set of Navier-Stokes and heat equations. The control is applied through Dirichlet boundary conditions.
We concentrate on a two-dimensional mode and use a semidiscrete Galerkin scheme for numerical computations. We construct both a linear control and a non-linear quadratic control and apply them to the full non-linear model. First, we test these controllers on a one-mode approximation. The convergence of the numerical scheme is analyzed. We also consider LQR control for a two-dimensional heat equation.Ph. D.
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Andoh, Fukashi. "Control of distributed parameter systems using Piezoelectric transducers /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486400446370949.
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Hill, David Dean. "Finite dimensional approximations of distributed parameter control systems." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54383.
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In this paper we consider two separate approaches to the development of finite dimensional control systems for approximating distributed parameter models. One method uses the “standard finite element” approximations to construct the basic system matrices. The resulting system can then be balanced by any of several balancing algorithms. The second method is based on truncating infinite dimensional balanced realizations of the input-output map. Both approaches are applied to a control problem governed by the heat equation. We present a comparison of the resulting finite dimensional models.Ph. D.
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Godasi, Satyam. "Identification and control of non-linear distributed parameter systems /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Jayaraman, Usha. "Toward the development of control software for an operator interface in the distributed automation environment." Master's thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-04122010-083449/.
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Evans, Katie Allison. "Reduced Order Controllers for Distributed Parameter Systems." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/11063.
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Distributed parameter systems (DPS) are systems defined on infinite dimensional spaces. This includes problems governed by partial differential equations (PDEs) and delay differential equations. In order to numerically implement a controller for a physical system we often first approximate the PDE and the PDE controller using some finite dimensional scheme. However, control design at this level will typically give rise to controllers that are inherently large-scale. This presents a challenge since we are interested in the design of robust, real-time controllers for physical systems. Therefore, a reduction in the size of the model and/or controller must take place at some point. Traditional methods to obtain lower order controllers involve reducing the model from that for the PDE, and then applying a standard control design technique. One such model reduction technique is balanced truncation. However, it has been argued that this type of method may have an inherent weakness since there is a loss of physical information from the high order, PDE approximating model prior to control design. In an attempt to capture characteristics of the PDE controller before the reduction step, alternative techniques have been introduced that can be thought of as controller reduction methods as opposed to model reduction methods. One such technique is LQG balanced truncation. Only recently has theory for LQG balanced truncation been developed in the infinite dimensional setting. In this work, we numerically investigate the viability of LQG balanced truncation as a suitable means for designing low order, robust controllers for distributed parameter systems. We accomplish this by applying both balanced reduction techniques, coupled with LQG, MinMax and central control designs for the low order controllers, to the cable mass, Klein-Gordon, and Euler-Bernoulli beam PDE systems. All numerical results include a comparison of controller performance and robustness properties of the closed loop systems.Ph. D.
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Vugrin, Eric D. "On Approximation and Optimal Control of Nonnormal Distributed Parameter Systems." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/11149.
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For more than 100 years, the Navier-Stokes equations and various linearizations have been used as a model to study fluid dynamics. Recently, attention has been directed toward studying the nonnormality of linearized problems and developing convergent numerical schemes for simulation of these sytems. Numerical schemes for optimal control problems often require additional properties that may not be necessary for simulation; these properties can be critical when studying nonnormal problems. This research is concerned with approximating infinite dimensional optimal control problems with nonnormal system operators.
We examine three different finite element methods for a specific convection-diffusion equation and prove convergence of the infinitesimal generators. Additionally, for two of these schemes, we prove convergence of the associated feedback gains. We apply these three schemes to control problems and compare the performance of all three methods.Ph. D.
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Thull, Daniel [Verfasser]. "Tracking Control of Mechanical Distributed Parameter Systems with Applications / Daniel Thull." Aachen : Shaker, 2010. http://d-nb.info/112086397X/34.
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Qi, Chenkun. "Modeling of nonlinear distributed parameter system for industrial thermal processes /." access full-text access abstract and table of contents, 2009. http://libweb.cityu.edu.hk/cgi-bin/ezdb/thesis.pl?phd-meem-b23750911f.pdf.
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Thesis (Ph.D.)--City University of Hong Kong, 2009."Submitted to Department of Manufacturing Engineering and Engineering Management in partial fulfillment of the requirements for the degree of Doctor of Philosophy." Includes bibliographical references (leaves 167-187)
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Banach, Antoni StanisŁaw. "Feedback design for nonlinear distributed-parameter systems by extended linearization." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/39429.
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A feedback design procedure known as extended linearization consists in replacing a mathematical model of a nonlinear dynamical system with its family of linearizations, parametrized by the operating point, and then combining feedback gains designed for representatives of the family into a single nonlinear feedback law.
The principles of the procedure, applicable both to lumped-parameter and distributed-parameter systems, are discussed at the outset. The development shows limits on feedback laws that can be designed, as well as nonuniqueness of solutions, inherent in the method.Ph. D.
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Ummethala, Upendra V. "Control of heat conduction in manufacturing processes : a distributed parameter systems approach." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/44894.
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Abou, Jaoude Dany. "Computationally Driven Algorithms for Distributed Control of Complex Systems." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/85965.
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This dissertation studies the model reduction and distributed control problems for interconnected systems, i.e., systems that consist of multiple interacting agents/subsystems. The study of the analysis and synthesis problems for interconnected systems is motivated by the multiple applications that can benefit from the design and implementation of distributed controllers. These applications include automated highway systems and formation flight of unmanned aircraft systems.
The systems of interest are modeled using arbitrary directed graphs, where the subsystems correspond to the nodes, and the interconnections between the subsystems are described using the directed edges. In addition to the states of the subsystems, the adopted frameworks also model the interconnections between the subsystems as spatial states. Each agent/subsystem is assumed to have its own actuating and sensing capabilities. These capabilities are leveraged in order to design a controller subsystem for each plant subsystem. In the distributed control paradigm, the controller subsystems interact over the same interconnection structure as the plant subsystems.
The models assumed for the subsystems are linear time-varying or linear parameter-varying. Linear time-varying models are useful for describing nonlinear equations that are linearized about prespecified trajectories, and linear parameter-varying models allow for capturing the nonlinearities of the agents, while still being amenable to control using linear techniques. It is clear from the above description that the size of the model for an interconnected system increases with the number of subsystems and the complexity of the interconnection structure. This motivates the development of model reduction techniques to rigorously reduce the size of the given model. In particular, this dissertation presents structure-preserving techniques for model reduction, i.e., techniques that guarantee that the interpretation of each state is retained in the reduced order system. Namely, the sought reduced order system is an interconnected system formed by reduced order subsystems that are interconnected over the same interconnection structure as that of the full order system. Model reduction is important for reducing the computational complexity of the system analysis and control synthesis problems.
In this dissertation, interior point methods are extensively used for solving the semidefinite programming problems that arise in analysis and synthesis.Ph. D.
The work in this dissertation is motivated by the numerous applications in which multiple agents interact and cooperate to perform a coordinated task. Examples of such applications include automated highway systems and formation flight of unmanned aircraft systems. For instance, one can think of the hazardous conditions created by a fire in a building and the benefits of using multiple interacting multirotors to deal with this emergency situation and reduce the risks on humans. This dissertation develops mathematical tools for studying and dealing with these complex systems. Namely, it is shown how controllers can be designed to ensure that such systems perform in the desired way, and how the models that describe the systems of interest can be systematically simplified to facilitate performing the tasks of mathematical analysis and control design.
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Rao, Sachit Srinivasa. "Sliding mode control in mechanical, electrical and thermal distributed processes." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164817694.
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Burke, Shawn E. "Shape and vibration control of distributed parameter systems : extension of multivariable concepts using spatial transforms." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/17239.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1989.Vita.
Includes bibliographical references (v. 2, leaves 273-285).
by Shawn Edmund Burke.
Ph.D.
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Schwartz, Jana Lyn. "The Distributed Spacecraft Attitude Control System Simulator: From Design Concept to Decentralized Control." Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/28269.
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A spacecraft formation possesses several benefits over a single-satellite mission. However, launching a fleet of satellites is a high-cost, high-risk venture. One way to mitigate much of this risk is to demonstrate hardware and algorithm performance in groundbased testbeds. It is typically difficult to experimentally replicate satellite dynamics in an Earth-bound laboratory because of the influences of gravity and friction. An air bearing provides a very low-torque environment for experimentation, thereby recapturing the freedom of the space environment as effectively as possible. Depending upon con- figuration, air-bearing systems provide some combination of translational and rotational freedom; the three degrees of rotational freedom provided by a spherical air bearing are ideal for investigation of spacecraft attitude dynamics and control problems.
An interest in experimental demonstration of formation flying led directly to the development of the Distributed Spacecraft Attitude Control System Simulator (DSACSS). The DSACSS is a unique facility, as it uses two air-bearing platforms working in concert. Thus DSACSS provides a pair of "spacecraft" three degrees of attitude freedom each. Through use of the DSACSS we are able to replicate the relative attitude dynamics between nodes of a formation such as might be required for co-observation of a terrestrial target.
Many dissertations present a new mathematical technique or prove a new theory. This dissertation presents the design and development of a new experimental system. Although the DSACSS is not yet fully operational, a great deal of work has gone into its development thus far. This work has ranged from configuration design to nonlinear analysis to structural and electrical manufacturing. In this dissertation we focus on the development of the attitude determination subsystem. This work includes development of the equations of motion and analysis of the sensor suite dynamics. We develop nonlinear filtering techniques for data fusion and attitude estimation, and extend this problem to include estimation of the mass properties of the system. We include recommendations for system modifications and improvements.Ph. D.
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Schmidt, Michael. "Systematic discretization of input, output maps and other contributions to the control of distributed parameter systems." [S.l.] : [s.n.], 2007. http://opus.kobv.de/tuberlin/volltexte/2007/1569.
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Paruchuri, Sai Tej. "Output Regulation of Systems Governed by Delay Differential Equations: Approximations and Robustness." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/98409.
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This thesis considers the problem of robust geometric regulation for tracking and disturbance rejection of systems governed by delay differential equations. It is well known that geometric regulation can be highly sensitive to system parameters and hence such designs are not always robust. In particular, when employing numerical approximations to delay systems, the resulting finite dimensional models inherit natural approximation errors that can impact robustness. This demonstrates this lack of robustness and then addresses robustness by employing versions of robust regulation that have been developed for infinite dimensional systems. Numerical examples are given to illustrate the ideas and to test the robustness of the regulator.M.S.
Recent years have seen a surge in the everyday application of complex mechanical and electrical systems. These systems can perform complex tasks; however, the increased complexity makes it harder to control them. An example of such a system is a semi-autonomous car designed to stay within a designated lane. One of the most commonly used approaches for controlling such systems is called output regulation. In the above example, the output regulator regulates the output of the car (position of the car) to follow the reference output (the road lane). Traditionally, the design of output regulators assumes complete knowledge of the system. However, it is impossible to derive equations that govern complex systems like a car. This thesis analyzes the robustness of output regulators in the presence of errors in the system. In particular, the focus is on analyzing output regulators implemented to delay-differential equations. These are differential equations where the rate of change of states at the current time depends on the states at previous times. Furthermore, this thesis addresses this problem by employing the robust versions of the output regulators.
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Norlander, Hans. "Modelling and Control Methods with Applications to Mechanical Waves." Doctoral thesis, Uppsala universitet, Avdelningen för systemteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-229793.
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Models, modelling and control design play important parts in automatic control. The contributions in this thesis concern topics in all three of these concepts. The poles are of fundamental importance when analyzing the behaviour of a system, and pole placement is an intuitive and natural approach for control design. A novel parameterization for state feedback gains for pole placement in the linear multiple input case is presented and analyzed. It is shown that when the open and closed loop poles are disjunct, every state feedback gain can be parameterized. Other properties are also investigated. Hammerstein models have a static non-linearity on the input. A method for exact compensation of such non-linearities, combined with introduction of integral action, is presented. Instead of inversion of the non-linearity the method utilizes differentiation, which in many cases is simpler. A partial differential equation (PDE) can be regarded as an infinite order model. Many model based control design techniques, like linear quadratic Gaussian control (LQG), require finite order models. Active damping of vibrations in a viscoelastic beam, modelled as a PDE, is considered. The beam is actuated by piezoelectric elements and its movements are measured by strain gauges. LQG design is used, for which different finite order models, approximating the PDE model, are constructed. The so obtained controllers are evaluated on the original PDE model. Minimization of the measured strain yields a satisfactory performance, but minimization of transversal deflection does not. The effect of the model accuracy of the finite order model approximations is also investigated. It turns out that a model with higher accuracy in a specified frequency interval gives controllers with better performance. The wave equation is another PDE. A PDE model, with one spatial dimension, is established. It describes wave propagation in a tube perforated with helical slots. The model describes waves of both extensional and torsional type, as well as the coupling between the two wave types. Experimental data are used for estimation of model parameters, and for assessment of the proposed model in two different cases. The model is found adequate when certain geometrical assumptions are valid.
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Yu, Mingzhao. "Model Reduction and Nonlinear Model Predictive Control of Large-Scale Distributed Parameter Systems with Applications in Solid Sorbent-Based CO2 Capture." Research Showcase @ CMU, 2017. http://repository.cmu.edu/dissertations/887.
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This dissertation deals with some computational and analytic challenges for dynamic process operations using first-principles models. For processes with significant spatial variations, spatially distributed first-principles models can provide accurate physical descriptions, which are crucial for offline dynamic simulation and optimization. However, the large amount of time required to solve these detailed models limits their use for online applications such as nonlinear model predictive control (NMPC). To cope with the computational challenge, we develop computationally efficient and accurate dynamic reduced order models which are tractable for NMPC using temporal and spatial model reduction techniques. Then we introduce an input and state blocking strategy for NMPC to further enhance computational efficiency. To improve the overall economic performance of process systems, one promising solution is to use economic NMPC which directly optimizes the economic performance based on first-principles dynamic models. However, complex process models bring challenges for the analysis and design of stable economic NMPC controllers. To solve this issue, we develop a simple and less conservative regularization strategy with focuses on a reduced set of states to design stable economic NMPC controllers. In this thesis, we study the operation problems of a solid sorbent-based CO2 capture system with bubbling fluidized bed (BFB) reactors as key components, which are described by a large-scale nonlinear system of partial-differential algebraic equations. By integrating dynamic reduced models and blocking strategy, the computational cost of NMPC can be reduced by an order of magnitude, with almost no compromise in control performance. In addition, a sensitivity based fast NMPC algorithm is utilized to enable the online control of the BFB reactor. For economic NMPC study, compared with full space regularization, the reduced regularization strategy is simpler to implement and lead to less conservative regularization weights. We analyze the stability properties of the reduced regularization strategy and demonstrate its performance in the economic NMPC case study for the CO2 capture system.
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Bonis, Ioannis. "Optimisation and control methodologies for large-scale and multi-scale systems." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/optimisation-and-control-methodologies-for-largescale-and-multiscale-systems(6c4a4f13-ebae-4d9d-95b7-cca754968d47).html.
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Distributed parameter systems (DPS) comprise an important class of engineering systems ranging from "traditional" such as tubular reactors, to cutting edge processes such as nano-scale coatings. DPS have been studied extensively and significant advances have been noted, enabling their accurate simulation. To this end a variety of tools have been developed. However, extending these advances for systems design is not a trivial task . Rigorous design and operation policies entail systematic procedures for optimisation and control. These tasks are "upper-level" and utilize existing models and simulators. The higher the accuracy of the underlying models, the more the design procedure benefits. However, employing such models in the context of conventional algorithms may lead to inefficient formulations. The optimisation and control of DPS is a challenging task. These systems are typically discretised over a computational mesh, leading to large-scale problems. Handling the resulting large-scale systems may prove to be an intimidating task and requires special methodologies. Furthermore, it is often the case that the underlying physical phenomena span various temporal and spatial scales, thus complicating the analysis. Stiffness may also potentially be exhibited in the (nonlinear) models of such phenomena. The objective of this work is to design reliable and practical procedures for the optimisation and control of DPS. It has been observed in many systems of engineering interest that although they are described by infinite-dimensional Partial Differential Equations (PDEs) resulting in large discretisation problems, their behaviour has a finite number of significant components , as a result of their dissipative nature. This property has been exploited in various systematic model reduction techniques. Of key importance in this work is the identification of a low-dimensional dominant subspace for the system. This subspace is heuristically found to correspond to part of the eigenspectrum of the system and can therefore be identified efficiently using iterative matrix-free techniques. In this light, only low-dimensional Jacobians and Hessian matrices are involved in the formulation of the proposed algorithms, which are projections of the original matrices onto appropriate low-dimensional subspaces, computed efficiently with directional perturbations.The optimisation algorithm presented employs a 2-step projection scheme, firstly onto the dominant subspace of the system (corresponding to the right-most eigenvalues of the linearised system) and secondly onto the subspace of decision variables. This algorithm is inspired by reduced Hessian Sequential Quadratic Programming methods and therefore locates a local optimum of the nonlinear programming problem given by solving a sequence of reduced quadratic programming (QP) subproblems . This optimisation algorithm is appropriate for systems with a relatively small number of decision variables. Inequality constraints can be accommodated following a penalty-based strategy which aggregates all constraints using an appropriate function , or by employing a partial reduction technique in which only equality constraints are considered for the reduction and the inequalities are linearised and passed on to the QP subproblem . The control algorithm presented is based on the online adaptive construction of low-order linear models used in the context of a linear Model Predictive Control (MPC) algorithm , in which the discrete-time state-space model is recomputed at every sampling time in a receding horizon fashion. Successive linearisation around the current state on the closed-loop trajectory is combined with model reduction, resulting in an efficient procedure for the computation of reduced linearised models, projected onto the dominant subspace of the system. In this case, this subspace corresponds to the eigenvalues of largest magnitude of the discretised dynamical system. Control actions are computed from low-order QP problems solved efficiently online.The optimisation and control algorithms presented may employ input/output simulators (such as commercial packages) extending their use to upper-level tasks. They are also suitable for systems governed by microscopic rules, the equations of which do not exist in closed form. Illustrative case studies are presented, based on tubular reactor models, which exhibit rich parametric behaviour.
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Rensfelt, Agnes. "Viscoelastic Materials : Identification and Experiment Design." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-111283.
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Luna, Pacho Julio Alberto. "Development of control systems and state observers for efficiency and durability improvement in PEM fuel cell based systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/458885.
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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 given to the electrochemically active surface area (ECSA). The ECSA in the cathode catalyst layer (CCL) is modelled using a twophase water model at the cathode side of the fuel cell to better represent its effect on the output voltage. The BoP ancillaries are considered as a parasitic power consumption that has to be delivered by the fuel cell. The most relevant parasitic power consumption is that of the compressor, which is modelled to include its dynamic behaviour in the control strategies.
Once the model equations are presented, model-based nonlinear distributed parameters observers (NDPO) are developed in the third part of the thesis. First, the partial differential equations (PDE) of the PEM fuel cell-based system are discretised and reformulated to obtain the observation model. Using this model, two novel sliding mode control (SMC) approaches for the observation of the internal conditions of the fuel cell are presented and compared, using the NEDC current profile as the case study for the simulations.
The fourth part of the thesis is devoted to model-based predictive control of the PEM fuel cell-based system. In particular, a nonlinear model predictive control (NMPC) strategy is proposed to improve the efficiency and at the same time, enhance the lifetime of the fuel cell. The use of the NDPOs in the control scheme facilitates critical information about the internal conditions of the fuel cell. This allows to design advanced control objectives that would not be achievable if using only the limited measurements that are available in PEM fuel cell-based systems. A multi-objective cost function that can prioritise between the different objectives of the controller during the optimisation procedure is designed. Finally, a discussion of the results obtained comparing different prioritisation between control objectives is provided.
The fifth and last part of the thesis is devoted to extract conclusions.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 tipo PEM. El modelo considera derivadas espaciales para representar el comportamiento de la dinámica interna de la pila. Dicha dinámica interna afecta la eficiencia y el grado de degradación del sistema. En la presente tesis, la degradación de la capa catalizadora se ve reflejada en la pérdida de área de la superficie electroquímicamente activa (ECSA). La ECSA en la capa catalizadora del cátodo (CCL) se modela utilizando un modelo bifásico de agua en el lado catódico de la pila, con el objeto de representar fielmente su efecto en el voltaje de salida. Una vez que las ecuaciones del modelo son presentadas, observadores no-lineales de parámetros distribuidos (NDPO) basados en modelo se desarrollan en la tercera parte del presente trabajo. Primero, las ecuaciones en derivadas parciales (PDE) de la pila de combustible de tipo PEM son discretizadas y reformuladas para obtener el modelo de observación. Utilizando este modelo, se presentan y comparan dos novedosos enfoques de control por modos deslizantes (SMC) para la observación de las condiciones internas de la pila de combustible. La cuarta parte de la presente tesis está dedicada al control predictivo basado en modelos del sistema de pila de combustible de tipo PEM. En particular, se propone una estrategia de controlador predictivo no-lineal basado en modelo (NMPC) para la mejora de la eficiencia y a la vez, la mejora del ciclo de vida de la pila de combustible. El uso de los NDPOs en el esquema de control suministra información crítica acerca de las condiciones internas en la pila de combustible. Este hecho permite el diseño de objetivos de control avanzados que no serían realizables utilizando únicamente las limitadas mediciones que están disponibles en los sistemas basados en pilas de combustible de tipo PEM. La quinta y última parte de la tesis está dedicada a la extracción de conclusiones.
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Humeau, Jean-Pierre. "Commande de systemes thermiques." Nantes, 1987. http://www.theses.fr/1987NANT2049.
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Bagdouri, Mohammed el. "Commande optimale d'un systeme thermique non lineaire." Nantes, 1987. http://www.theses.fr/1987NANT2023.
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Etude de problemes de commande d'un systeme thermique, le modele considere etant un systeme non lineaire a parametres repartis. La non-linearite peut etre due a la variation des caracteristiques thermophysiques du systeme en fonction de la temperature ou a un phenomene de changement de phase entrainant un saut dans l'enthalpie du systeme
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Bresch-Pietri, Delphine. "Commande robuste de systèmes à retard variable : Contributions théoriques et applications au contrôle moteur." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00803271.
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Cette thèse étudie la compensation robuste d'un retard de commande affectant un système dynamique. Pour répondre aux besoins du domaine applicatif du contrôle moteur, nous étudions d'un point de vue théorique des lois de contrôle par prédiction, dans les cas de retards incertains et de retards variables, et présentons des résultats de convergence asymptotique. Dans une première partie, nous proposons une méthodologie générale d'adaptation du retard, à même de traiter également d'autres incertitudes par une analyse de Lyapunov-Krasovskii. Cette analyse est obtenue grâce à une technique d'ajout de dérivateur récemment proposée dans la littérature et exploitant une modélisation du retard sous forme d'une équation à paramètres distribués. Dans une seconde partie, nous établissons des conditions sur les variations admissibles du retard assurant la stabilité du système boucle fermée. Nous nous intéressons tout particulièrement à une famille de retards dépendant de la commande (retard de transport). Des résultats de stabilité inspirés de l'ingalité Halanay sont utilisés pour formuler une condition de petit gain permettant une compensation robuste. Des exemples illustratifs ainsi que des résultats expérimentaux au banc moteur soulignent la compatibilité de ces lois de contrôle avec les impératifs du temps réel ainsi que les mérites de cette approche.
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Vincent, Benjamin. "Modélisation et analyse des systèmes de commande multi-physiques." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAT091.
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Par multi-physiques systèmes, nous considérons les systèmes à paramètres distribués gouvernés par des lois de conservation. Ces dernières sont interconnectées par des phénomènes de transports et de couplages distribués. Cette thèse porte sur l'étude et le développement d'outils pour la modélisation et l'analyse de la classe de système pour des fins de commande. L'approche considérée repose sur la formulation géométrique des équations d'état avec la mise en œuvre des structures Hamiltoniennes à port et GENERIC. Ces formulations encodent les lois fondamentales de la physique, comme la première et la seconde loi de la thermodynamique. Les contributions portent sur la formulation structurée de systèmes multi-physiques. Des outils de réduction et de discrétisation pseudo-spectrale géométrique sont utilisés pour obtenir des modèles de commande. Une étude de stabilité et de passivité basée sur la production irréversible d'entropie est également proposée pour cette classe de systèmes. La thèse est motivée par deux applications distinctes : le problème de commande des profils de plasma dans les Tokamaks, et la réjection d'instabilités thermo-acoustiques dans un tube de Rijke. La première application vise à assurer un fonctionnement à l'état d'équilibre d'un réacteur de fusion par confinement magnétique. Les équations décrivant la dynamique du plasma à une échelle macroscopique sont les lois de conservation caractérisant les domaines physiques électromagnétiques et cinétiques (masse, moments et énergies). Des modèles structurés du plasma, avec la réaction de fusion, sont présentés sous forme 3-D, 1-D, et 0-D avec le formalisme Hamiltonien à port. Un modèle thermomagnétique du plasma est formulé avec le formalisme GENERIC ouvert. La seconde application illustre les concepts d'instabilités thermo-acoustiques que l'on retrouve par exemple dans les chambres à combustion. Le tube de Rijke est un tube vertical où une source de chaleur localisée est disposée dans sa partie inférieure. Sous certaines conditions, le processus d'échange de chaleur et le domaine acoustique sont interconnectés par un retour de boucle qui déstabilise le système. Cette instabilité se manifeste par la production d'un son bruyant% The thesis aims at studying and developing structured-based approaches for the modelling and analysis of distributed parameter systems where thermodynamic contributions cannot be neglected. Geometric formalisms are considered for the representation of this class of dynamical systems. Key contributions include structured modelling from first principle equations, structure-preserving geometric reduction and discretization, and passivity and stability analysis for multi-physics systems based on total irreversible entropy production. The thesis is motivated by two applications: the control of burning plasma profiles in Tokamaks; and, the rejection of thermoacoustic unstabilities in a Rijke's tube. The second application illustrates an instable thermoacoustic phenomenon arising experimentally under specific geometry and heating conditions within a vertical tube. Both systems are formulated as structured ones through port-Hamiltonian and GENERIC formalisms
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Alana, Jorge Enrique. "Optimal measurement locations for parameter estimation of distributed parameter systems." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/optimal-measurement-locations-for-parameter-estimation-of-distributed-parameter-systems(fffa31d8-2b19-434b-a2b6-7809e314bb55).html.
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Identifying the parameters with the largest influence on the predicted outputs of a model revealswhich parameters need to be known more precisely to reduce the overall uncertainty on themodel output. A large improvement of such models would result when uncertainties in the keymodel parameters are reduced. To achieve this, new experiments could be very helpful,especially if the measurements are taken at the spatio-temporal locations that allow estimate the parameters in an optimal way. After evaluating the methodologies available for optimal sensor location, a few observations were drawn. The method based on the Gram determinant evolution can report results not according to what should be expected. This method is strongly dependent of the sensitivity coefficients behaviour. The approach based on the maximum angle between subspaces, in some cases, produced more that one optimal solution. It was observed that this method depends on the magnitude of outputs values and report the measurement positions where the outputs reached their extrema values. The D-optimal design method produces number and locations of the optimal measurements and it depends strongly of the sensitivity coefficients, but mostly of their behaviours. In general it was observed that the measurements should be taken at the locations where the extrema values (sensitivity coefficients, POD modes and/or outputs values) are reached. Further improvements can be obtained when a reduced model of the system is employed. This is computationally less expensive and the best estimation of the parameter is obtained, even with experimental data contaminated with noise. A new approach to calculate the time coefficients belonging to an empirical approximator based on the POD-modes derived from experimental data is introduced. Additionally, an artificial neural network can be used to calculate the derivatives but only for systems without complex nonlinear behaviour. The latter two approximations are very valuable and useful especially if the model of the system is unknown.
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Chander, R. "Identification of distributed parameter systems with damping." Diss., Georgia Institute of Technology, 1988. http://hdl.handle.net/1853/13386.
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Liu, Yi. "Grey-box Identification of Distributed Parameter Systems." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-220.
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Barkman, Patrik. "Grey-box modelling of distributed parameter systems." Thesis, KTH, Beräkningsvetenskap och beräkningsteknik (CST), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-240677.
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Grey-box models are constructed by combining model components that are derived from first principles with components that are identified empirically from data. In this thesis a grey-box modelling method for describing distributed parameter systems is presented. The method combines partial differential equations with a multi-layer perceptron network in order to incorporate prior knowledge about the system while identifying unknown dynamics from data. A gradient-based optimization scheme which relies on the reverse mode of automatic differentiation is used to train the network. The method is presented in the context of modelling the dynamics of a chemical reaction in a fluid. Lastly, the grey-box modelling method is evaluated on a one-dimensional and two-dimensional instance of the reaction system. The results indicate that the grey-box model was able to accurately capture the dynamics of the reaction system and identify the underlying reaction.Hybridmodeller konstrueras genom att kombinera modellkomponenter som härleds från grundläggande principer med modelkomponenter som bestäms empiriskt från data. I den här uppsatsen presenteras en metod för att beskriva distribuerade parametersystem genom hybridmodellering. Metoden kombinerar partiella differentialekvationer med ett neuronnätverk för att inkorporera tidigare känd kunskap om systemet samt identifiera okänd dynamik från data. Neuronnätverket tränas genom en gradientbaserad optimeringsmetod som använder sig av bakåt-läget av automatisk differentiering. För att demonstrera metoden används den för att modellera kemiska reaktioner i en fluid. Metoden appliceras slutligen på ett en-dimensionellt och ett två-dimensionellt exempel av reaktions-systemet. Resultaten indikerar att hybridmodellen lyckades återskapa beteendet hos systemet med god precision samt identifiera den underliggande reaktionen.
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Agrawal, Janak. "Distributed parameter estimation for complex energy systems." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/129082.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, September, 2020Cataloged from student-submitted PDF of thesis.
Includes bibliographical references (pages 81-83).
With multiple energy sources, diverse energy demands, and heterogeneous socioeconomic factors, energy systems are becoming increasingly complex. Multifaceted components have non-linear dynamics and are interacting with each other as well as the environment. In this thesis, we model components in terms of their own internal dynamics and output variables at the interfaces with the neighboring components. We then propose to use a distributed estimation method for obtaining the parameters of the the component's internal model based on the measurements at its interfaces. We check whether theoretical conditions for distributed estimation approach are met and validate the results obtained. The estimated parameters of the system can then be used for advanced control purposes in the HVAC system. We also use the measurements at the terminals to model and verify the components in the energy-space which is a novel approach proposed by our group. The energy space approach reflects conservation of power and rate of change of reactive power. Both power and rate of change of generalized reactive power are obtained from measurements at the input and output ports of the components by measuring flows and efforts associated with their ports. A pair of flow and efforts is measured for electrical and gas ports, as well as for fluids. We show that the energy space model agrees with the conventional state space model with a high accuracy and that standard measurements available in a commercial HVAC can be used for calculating the interaction variables in the energy space model. A novel finding is that unless measurements of both flow and effort variables is used, the sub-model representing rate of change of reactive power can not be validated. This implies that commonly used models in engineering which assume constant effort variables may not be sufficiently accurate to support most efficient control of complex interconnected systems comprising multiple energy conversion processes.
by Janak Agrawal.
M. Eng.
M.Eng. Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science
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Norris, Mark A. "Parameter identification in distributed structures." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/71164.
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This dissertation develops two new techniques for the identification of parameters in distributed-parameter systems. The first technique identifies the physical parameter distributions such as mass, damping and stiffness. The second technique identifies the modal quantities of self-adjoint distributed-parameter systems.
Distributed structures are distributed-parameter systems characterized by mass, damping and stiffness distributions. To identify the distributions, a new identification technique is introduced based on the finite element method. With this approach, the object is to identify "average" values of mass, damping and stiffness distributions over each finite element. This implies that the distributed parameters are identified only approximately, in the same way in which the finite element method approximates the behavior of a structure.
It is common practice to represent the motion of a distributed parameter system by a linear combination of the associated modes of vibration. In theory, we have an infinite set of modes although, in practice we are concerned with only a finite linear combination of the modes. The modes of vibration possess certain properties which distinguish them from one another. Indeed, the modes of vibration are uncorrelated in time and orthogonal in space. The modal identification technique introduced in this dissertation uses path these spatial properties. Because both the temporal and spatial properties are used, the method does not encounter problems when the natural frequencies are closely-spaced or repeated.Ph. D.
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Vayena, Olga. "Distributed parameter control in rapid thermal processing (RTP) /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2004.
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Thesis (Ph.D.)--Tufts University, 2004.Adviser: Haris Doumanidis. Submitted to the Dept. of Mechanical Engineering. Includes bibliographical references (leaves 123-129). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Miller, Scott E. (Scott Edward). "Distributed parameter active vibration control of smart structures." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/33473.
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Villegas, Janvier Andres. "A port-Hamiltonian approach to distributed parameter systems." Enschede : University of Twente [Host], 2007. http://doc.utwente.nl/57842.
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Luna, Ortiz J. E. "Optimization of distributed parameter systems using transient simulators." Thesis, University of Manchester, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503592.
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Li, Peng. "Controllability, stability and stabilizability of distributed parameter systems." Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7851.
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In this thesis the question of stabilization of perturbed (or uncertain) infinite dimensional linear systems is considered. First, we identify the class of perturbations for which the system remains controllable thereby stabilizable by the same feedback law as for the nominal system. That is, sufficient conditions are presented that guarantee stabilizability of the perturbed system given that the unperturbed system has similar properties. Secondly, we present a methodology for designing feedback controllers such that the feedback system is stable. It is shown that exponential stability can be achieved by choice of suitable additional state feedback controls even in the presence of unbounded and nonlinear perturbations. Both deterministic and stochastic systems are considered. Finally, we apply these stabilization results to a simplified SCOLE model proposed by NASA. Numerical simulations are carried out to illustrate the impact of perturbations on the performance of the space structures and the effectiveness of the stabilizing control.
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Sawo, Felix. "Nonlinear state and parameter estimation of spatially distributed systems." Karlsruhe Univ.-Verl. Karlsruhe, 2009. http://d-nb.info/994500211/04.
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Wood, Giles David. "Control of parameter-dependent mechanical systems." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/252135.
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Costello, Zachary Kohl. "Distributed computation in networked systems." Diss., Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/54924.
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The objective of this thesis is to develop a theoretical understanding of computation in networked dynamical systems and demonstrate practical applications supported by the theory. We are interested in understanding how networks of locally interacting agents can be controlled to compute arbitrary functions of the initial node states. In other words, can a dynamical networked system be made to behave like a computer? In this thesis, we take steps towards answering this question with a particular model class for distributed, networked systems which can be made to compute linear transformations.
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Alipourazadi, Shahram. "New approaches to linear graph modeling of distributed-parameter systems." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/41896.
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Analytical modeling is an important fundamental step in the development of procedures such as simulation, design, control, and health monitoring of engineering systems. Typically, physical properties such as inertia, flexibility (or stiffness), capacitance, inductance, and energy dissipation (mechanical damping or electrical resistance) are spatially distributed in a physical dynamic system. Often in dynamic models, these characteristics are approximated by spatially “lumped” elements. For better accuracy, however, the true distributed nature of these parameters has to be incorporated into the model. Distributed parameter (DP) models are important in this context. This thesis concerns the representation of distributed parameter engineering systems using linear graphs (LG).
Among possible approaches for modeling of engineering systems, linear graphs are used in the present work due to its numerous advantages as discussed in the thesis. An engineering system may possess physical properties in many domains such as mechanical, electrical, thermal, and fluid. Mechatronic systems are multi-domain systems, which typically possess at least electro-mechanical characteristics. Linear graphs present a domain-independent unified approach for modeling multi-domain systems. Furthermore, linear graphs have beneficial features in the development of automatic procedures for modeling and designing engineering systems, which are long-term goals of the present work.
In this thesis, approaches are developed for the representation of distributed-parameter systems as LG models. Different approaches are presented for this purpose and compared. The LG modeling approach enables one to visualize the system structure before formulating the dynamic equations of the system. For example, for a DP system the structure of its LG model may possess a well-defined pattern. In this work, vector linear graphs are introduced to take advantage of these patterns. General notations and elements are defined for vector linear graphs. As a result of this development a new single element is generated for use in the modeling of distributed-parameter systems, particularly in the mechanical domain.
In this thesis, a software toolbox is enhanced and presented for LG modeling, which is able to automatically extract the state space equations of a mechatronic system. This software tool is provided free for academic use and is accessible through the Internet. Throughout the thesis many comprehensive examples are provided to illustrate the developed concepts and procedures and their application.
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Khalil, Ashraf F. "Networked control of distributed energy systems." Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3380/.
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This thesis reports a new method for stability analysis and maximum time delay estimation in networked control systems with applications to distributed energy systems. The proposed new method is based on using finite difference approximation for the delay term and then the Lyapunov system stability theorem is applied to derive the time delay boundary allowed to the system. The proposed method has been applied to networked control systems with state feedback controllers, with dynamic controllers, and to multi-units interconnected networked control systems. The proposed method is then extended to a class of networked control system with bounded nonlinearity and uncertainties. It is found that increasing the nonlinearity in the system will result in decreasing the maximum allowable time delay. Compared with most of the methods reported in the published literature, the new method is simple to use while the results are comparable. When the time delay is modelled using Markov Chain the stability of the networked control system is formulated as finding the solutions for Bilinear Matrix Inequalities. An improved V-K iteration algorithm is used to solve the Bilinear Matrix Inequalities in order to derive a controller to stabilize the systems.
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Reinschke, Johannes Ullrich. "H∞-control of spatially distributed systems." Thesis, University of Cambridge, 1999. https://www.repository.cam.ac.uk/handle/1810/251474.
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Hamid, Tariq Parwaiz. "Control of distributed objects." Thesis, University of the West of Scotland, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260344.
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Lundin, Mats. "Building Distributed Control Systems Using Distributed Active Real-Time Databases." Thesis, University of Skövde, Department of Computer Science, 1998. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-234.
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From the field of control theory, we can see that varying communication delays in a control system may be hard or even impossible to handle. From this point of view it is preferable to have these delays bounded and as small and as possible in order to adapt the control process to them. On the other hand, in some cases delays are inevitable and must be handled by the control system.
A control system may for different reasons be distributed, e.g., because of a distributed environment or severe environment demands such as heat or dust at some locations. Information in such a system will suffer from delays due to transportation from one place to another. These delays often show up in a random fashion, especially if a general network is used for transportation. Another source of delays is the system environment itself. For predictability reasons a real-time database is preferable if the delays are to be controlled.
A straightforward way of handling delays in a control system is to build the system such that delays are constant, i.e., to build a time invariant system. The time from sensor reading to actuation is made constant either by adding a suitable delay to achieve a total constant delay or by using time-triggered reading and actuation. These are simple ways of controlling the delays, but may be very inefficient because worst-case execution time must always be used. Other ways of handling varying delays are by using more tolerant control algorithms. There are two suitable control models proposed by Nilsson (1998) for this purpose. The tolerant algorithm approach is assumed in this work.
This thesis uses a distributed active real-time database system as a basis for building control systems. One of the main objectives is to determine how active functionality can be used to express the control system, i.e., how rules in the database can be used to express the control algorithm and for handling propagation of information. Another objective is to look at how the choice of consistency level in the database affects the result of the control system, i.e. how different consistency level affects the delays. Of interest is also to characterize what type of applications each level is suited for.
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Zhang, Hanzhong. "A moving boundary problem in a distributed parameter system with application to diode modeling." Access restricted to users with UT Austin EID, 2001. http://wwwlib.umi.com/cr/utexas/fullcit?p3037035.
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Abeysekera, Don Cecil Rohantha. "Performance of thread based distributed systems." Thesis, University of Kent, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334084.
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Ndumu, Abongwa Ndita. "Interacting neural networks : an architecture for modelling distributed parameter dynamical systems." Thesis, University of Central Lancashire, 1999. http://clok.uclan.ac.uk/18922/.
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The development of models of dynamical systems behaviour is a fundamental activity in science and engineering disciplines. This thesis examines the problem of modelling a class of dynamical systems using neural networks. Existing research reveals that neural network models have been developed for lumped parameter dynamical systems; that is, systems where the variables of interest vary only over the timedomain. However, there are no adequate neural network models for distributed parameter dynamical systems; that is, systems where the variables of interest vary over some other domain, e.g. the spatial domain, in addition to the time domaln. The main goal of this research is to develop a neural network architecture for modelling distributed dynamical systems where one has limited and incomplete knowledge about the underlying behaviour of the system. The result of this research is a generic neural network architecture - the Interacting Neural Network (INN) architecture - that is capable of modelling a wide range of distributed dynamical systems. The fundamental problem associated with distributed systems which the INN architecture addresses is that of scaling. The scaling problem manifests itself when the complexity of a model increases in a manner which is unmanageable as the problem size increases. The INN architecture solves the scaling problem by using the philosophy of interacting subsystems which is a general methodology for managing complexity. The underlying principle of this methodology is to view the system as a combination of many small subsystems and to focus the modelling effort at the subsystem level rather than at the system level. The resulting models are relatively simpler, but when allowed to interact, the complex behaviour of the original system can be retrieved. The capabilities of the INN architecture are investigated by comparing its performance with other architectures on two distributed systems. First, investigations are carried out in modelling non-linear heat flow which serves as a case study to expound the capabilities of the INN architecture. Secondly, the architecture is applied to an aquifer problem to illustrate its capabilities on modelling practical problems. It is shown that the INN architecture captures the underlying behaviour of both systems, and more significantly, that the trained network can generalise spatially, wherein the same trained network can be applied to different instances of a given system. The spatial generalisation capabilities of the INN architecture is a unique and powerful result, which when used appropriately can significantly extend the usefulness of neural network models. Finally, two major factors that affect the generalisation ability of the INN architecture are investigated: (i) the effect of changing the geometry of a given system and (ii) the effect of the amount of training data available. New relationships are deduced for both factors.
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Wen, Guoguang. "Distributed cooperative control for multi-agent systems." Phd thesis, Ecole Centrale de Lille, 2012. http://tel.archives-ouvertes.fr/tel-00818774.
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Cette thèse considère principalement trois problèmes dans le domaine du contrôle distribué coopératif des systèmes multi-agents(SMA): le consensus, la navigation en formation et le maintien en formation d'un groupe d'agents lorsqu'un agent disparait. Nous proposons 3 algorithmes pour résoudre le problème du calcul distribué d'un consensus à partir de l'approche leadeur-suiveur dans le contexte SMA à dynamique non-linéaire. La référence est définie comme un leader virtuel dont on n'obtient, localement, que les données de position et de vitesse. Pour résoudre le problème du suivi par consensus pour les SMA à dynamique non-linéaire, nous considérons le suivi par consensus pour SMA de premier ordre. On propose des résultats permettant aux suiveurs de suivre le leadeur virtuel en temps fini en ne considérant que les positions des agents. Ensuite, nous considérons le suivi par consensus de SMA de second. Dans le cas de la planification de trajectoire et la commande du mouvement de la formation multi-agents. L'idée est d'amener la formation, dont la dynamique est supposée être en 3D, d'une configuration initiale vers une configuration finale (trouver un chemin faisable en position et orientation) en maintenant sa forme tout le long du chemin en évitant les obstacles. La stratégie proposée se décompose en 3 étapes. Le problème du Closing-Rank se traduit par la réparation d'une formation rigide multi-agents "endommagée" par la perte de l'un de ses agents. Nous proposons 2 algorithmes d'autoréparation systématique pour récupérer la rigidité en cas de perte d'un agent. Ces réparations s'effectuent de manière décentralisée et distribuée n'utilisant que des informations de voisinage.
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Brose, Gerald. "Access control management in distributed object systems." [S.l. : s.n.], 2001. http://www.diss.fu-berlin.de/2001/203/index.html.
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