Dissertations / Theses on the topic 'Passivity-based control'
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Suryodipuro, Andika Diwaji School of Chemical Engineering & Industrial Chemistry UNSW. "Dynamic controllability analysis for linear multivariable processes based on passivity conditions." Awarded by:University of New South Wales. School of Chemical Engineering and Industrial Chemistry, 2005. http://handle.unsw.edu.au/1959.4/25714.
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The operation of a chemical process plant has become more complex with the addition of process integration and intensification. A greater emphasis on producing goods with the lowest product variability in the safest manner possible and stringent environmental regulation limiting the quantity of effluent release have all put more constraints on the physical and economic performance of the chemical plant. The performance of a plant is quantified by the ability of the process system to achieve its objectives, which is governed by its process design and control. The conventional approach to process design and control selection starts sequentially by proposing a process flowsheet for the plant. The selection criteria for a flowsheet are normally based only on its environmental impact and economic merits. It is after a process flowsheet is deemed financially suitable that process control development commences. However, a more integrated approach to process design and control stage may thus lead to a plant that has better achievable performance. The aim of this project is to provide a new approach to quantitative dynamic controllability analysis for integration of process design and control by using the concept of passivity and passive systems. Passivity is an input/output property of processes. Passive processes are stable and minimum phase and therefore very easy to control. For a given process, its shortage of passivity, which reflects destabilizing effects of factors such as time delays and Right-Half Plane (RHP) zeros, can be used to indicate its controllability. The project focuses in developing the proposed controllability analysis by combining the idea of passivity and IMC invertibility, which is then formulated into an optimization problem that can be solved by either using Semi-Definite Programming or Non-Linear Optimization. The achievable performance of the plant is quantified in terms of the sensitivity function of the open-loop process. The selection of a process from four different heat-integrated distillation column schemes was used as a case study and the result had clearly shown that the passivity-based controllability analysis was able to select a process based on the plant achievable performance under the constraint of passivity and design parameters.
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Nunna, Kameswarie. "Constructive interconnection and damping assignment passivity-based control with applications." Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/24587.
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Energy-based modeling and control of dynamical systems is crucial since energy is a fundamental concept in Science and Engineering theory and practice. While Interconnection and Damping Assignment Passivity-based Control (IDA-PBC) is a powerful theoretical tool to control port-controlled Hamiltonian (PCH) systems that arise from energy balancing principles, sensorless operation of energy harvesters is a promising practical solution for low-power energy generation. The thesis addresses these two problems of energy-based control and efficient energy generation. The design via IDA-PBC hinges on the solution of the so-called matching equation which is the stumbling block in making this method widely applicable. In the first part of the thesis, a constructive approach for IDA-PBC for PCH systems that circumvents the solution of the matching equation is presented. A new notion of solution for the matching equation, called algebraic solution, is introduced. This notion is instrumental for the construction of an energy function defined on an extended state-space. This yields, differently from the classical solution, a dynamic state-feedback that stabilizes a desired equilibrium point. In addition, conditions that preserve the PCH structure in the extended closed-loop system have been provided. The theory is validated on four examples: a two-dimensional nonlinear system, a magnetic levitated ball, an electrostatic microactuator and a third order food-chain system. For these systems damping structures that cannot be imposed with the standard approach are assigned. In the second part of the thesis, the design of a nonlinear observer and of an energy-based controller for sensorless operation of a rotational energy harvester is presented. A mathematical model of the harvester with its power electronic interface is developed. This model is used to design an observer that estimates the mechanical quantities from the measured electrical quantities. The gains of the observer depend on the solution of a modified Riccati equation. The estimated mechanical quantities are used in a feedback control law that sustains energy generation across a range of source rotation speeds. The proposed observer-controller scheme is assessed through simulations and experiments.
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Rutvika, Nandan Manohar. "Design of Distributed Stand-alone Power Systems using Passivity-based Control." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263619.
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VIOLA, GIUSEPPE. "Control of underactuated mechanical systems via passivity-based and geometric techniques." Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2008. http://hdl.handle.net/2108/507.
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Il controllo di sistemi meccanici è attualmente uno tra i più attivi settori di
ricerca, a causa delle diverse applicazioni di sistemi meccanici nella vita reale.
Gli ultimi decenni hanno visto un accresciuto interesse nel controllo di sistemi
meccanici sottoattuati. Questi sistemi sono caratterizzati dal possedere più
gradi di libertà che attuatori, vale a dire, uno o più gradi di libertà non sono attuati. Questa classe di sistemi meccanici è molto rappresentata nella vita reale.
Esempi ne sono navi, veicoli spaziali, veicoli sottomarini, elicotteri, automobili,
robot mobili, robot spaziali e manipolatori sottoattuati.
Questa tesi si concentra su differenti generalizzazioni di alcuni risultati esistenti sul controllo di questa classe di sistemi, presenti nel lavoro di A. Tornambè, R. Ortega e J. W. Grizzle, con i quali ho collaborato nei tre anni del dottorato. Questi risultati sono stati ottenuti usando due diversi approcci: quello
basato sulla passività e quello geometrico.
Tre classi di problemi vengono trattate:
1. Disaccoppiamento ingresso-uscita per sistemi meccanici lineari sottoattuati;
2. Stabilizzazione asintotica di equilibri arbitrari in sistemi meccanici non
lineari sottoattuati;
3. Stabilizzazione esponenziale di orbite periodiche in sistemi meccanici non
lineari sottoattuati soggetti a impatti, con applicazioni alla robotica bipede.Control of mechanical systems is currently among one of the most active fields of research, due to the diverse applications of mechanical systems in real life. The last decades have shown an increasing interest in the control of underactuated mechanical systems. These systems are characterized by the fact of possessing more degrees of freedom than actuators, i.e., one or more degrees of freedom are unactuated. This class of mechanical systems are abundant in real life; examples of such systems include surface vessels, spacecraft, underwater vehicles, helicopters, road vehicles, mobile robots, space robots and underactuated manipulators. The thesis focuses on different generalizations of some of the existing results on the control of this class of systems, given in the existing work of A. Tornamb, R. Ortega and J. W. Grizzle, who I collaborated with during the last three years. They have been attained by using techniques borrowed from two different approaches: the passivity-based and the geometric ones. Three classes of problems are dealt with, namely: 1. Input-output decoupling for linear underactuated mechanical systems; 2. asymptotic stabilization of arbitrary equilibria in nonlinear mechanical systems with underactuation degree one 3. exponential stabilization of periodic orbits in nonlinear underactuated mechanical systems with impulse effects, with applications to biped robot locomotion
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Kloiber, Tobias [Verfasser]. "Constructive Passivity-Based Control of Smooth and Switched Nonlinear Systems / Tobias Kloiber." Aachen : Shaker, 2015. http://d-nb.info/1070152137/34.
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Ryalat, Mutaz. "Design and implementation of nonlinear and robust control for Hamiltonian systems : the passivity-based control approach." Thesis, University of Southampton, 2015. https://eprints.soton.ac.uk/398131/.
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Recently, control techniques that adopt the geometrical structure and physical properties of dynamical systems have gained a lot of interest. In this thesis, we address nonlinear and robust control problems for systems represented by port-controlled Hamiltonian (PCH) models using the interconnection and damping assignment passivity-based control(IDA-PBC) methodology, which is the most notable technique facilitating the PCH framework. In this thesis, a novel constructive framework to simplify and solve the partial differential equations (PDEs) associated with IDA-PBC for a class of underactuated mechanical systems is presented. Our approach focuses on simplifying the potential energy PDEs to shape the potential energy function which is the most important procedure in the stabilization of mechanical systems. The simplification is achieved by parametrizing thedesired inertia matrix that shapes the kinetic energy function, thus achieving total energy shaping. The simplification removes some constraints (conditions and assumptions) that have been imposed in recently developed methods in literature, thus expanding the class of systems for which the methods can be applied including the separable PCH systems(systems with constant inertia matrix) and non-separable PCH systems (systems with non-constant inertia matrix). The results are illustrated through software simulations and hardware experiments on real engineering applications. We also propose an integral control and adaptive control schemes to improve the robustness of the IDA-PBC method in presence of uncertainty. We first provide some results for the case of fully-actuated mechanical systems, and then extend those results to underactuated systems which are more complex. Integral action control on both the passive and non-passive outputs in the IDA-PBC construction, a strategy to ensure the robustness of the systems by preserving its stability in face of external disturbances, is introduced, establishing the input-to-state stability (ISS) property. The results are applied to both the separable and non-separable PCH systems and illustrated via several simulations. The extension to the non-separable case exhibits more complicated design as we need to take into account the derivative of the inertia matrix. Finally, the IDA-PBC method is employed to solve an important nonlinear phenomenon called ‘pull-in’ instability associated with the electrostatically actuated microelectromechanical systems (MEMSs). The control construction is an output-feedback controller that ensures global asymptotic stability and avoids velocity measurement which may not be practically available. Furthermore, the integral, adaptive and ISS control schemes proposed in this thesis for mechanical systems are extended to facilitate the stabilization of electromechanical systems which exhibit strong coupling between different energy domains.
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Flemmer, Henrik. "Control Design and Performance Analysis of force Reflective Teleoperators - A Passivity Based Approach." Doctoral thesis, KTH, Machine Design, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3795.
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In this thesis, the problem of controlling a surgical masterand slave system with force reflection is studied. The problemof stiff contacts between the slave and the environment isgiven specific attention. The work has been carried out at KTHbased on an initial cooperation with Karolinska Sjukhuset. Theaim of the over all project is to study the possibilities forintroduction of a force reflective teleoperator in neurologicalskullbase operations for the particular task of bone millingand thereby, hopefully, increase patient safety, decreasesurgeon workload and cost forthe society.
The main contributions of this thesis are:
Derivation of a dynamical model of the master andoperators finger system and, experimental identificationof ranges on model parameter values. Based on this model, theinteraction channel controllers optimized for transparency arederived and modified to avoid the influence of the uncertainmodel parameters. This results in a three channel structure. Todecrease the influence of the uncertain parameters locally atthe master, a control loop is designed such that the frequencyresponse of the reflected force is relatively unaffected by theuncertainties, a result also confirmed in a transparencyanalysis based on the H-matrix. The developed teleoperatorcontrol structure is tested in experiments where the operatorcould alter the contact force without facing any problems aslong as the slave is in contact with the environment.
As a result of the severe difficulties for the teleoperatorto move from free space motion to in-contact manipulationwithout oscillative behaviour, a new detection algorithm basedon passivity theory is developed. The algorithm is able todetect the non-passive behaviour of the actual teleoperatorinduced by the discrete change in system dynamics occurring atthe contact instant. A stabilization controller to be activatedby the detection algorithm is designed and implemented on themaster side of the teleoperator. The detection algorithm andthe stabilization controller are shown highly effective in realexperiments.
All major research results presented in the thesis have beenverified experimentally.
KeywordsTeleoperator, Force Feedback, Passivity, StiffContacts, Control, Robustness, Transparency, Bone Milling,Uncertainty
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Mohammed, Ali. "PASSIVITY-BASED TRACKING CONTROL OF A ROBOT MANIPULATOR USING AN EXTENDED STATE OBSERVER." Cleveland State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=csu1590253786792864.
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Septham, Kamthon. "Linear mechanisms and pressure fluctuations in wall turbulence with passivity-based linear feedback control." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/58010.
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Full-domain, linear feedback control of turbulent channel flow at Reτ ≤ 400 is an effective method to attenuate turbulent fluctuations such that it is relaminarised. The passivity-based control approach is adopted and motivated by the conservative characteristics of the nonlinear terms in the Navier-Stokes equations with respect to the disturbance energy. The control acts on the wall-normal velocity fluctuations at low wavenumbers. The maximum spanwise wavelength that can be used without losing control is constant with Reynolds number at λ⁺z = 125. In the minimal flow unit at Re_cl = 5000, the maximum streamwise wavelength is λ⁺x ≈ 1000. The effect of control on the pressure components is investigated via the Green's function approach. Only the spanwise spectra of p_r up to the designated controlled spanwise wavenumber k_z are effectively suppressed by the linear control. This indicates that the linear control operates via vαU/αy and thus acts on the pressure field via the linear ("rapid") source term of the Poisson equation for pressure fluctuations, 2αU/αy αv/αx. The effectiveness of the linear control to suppress inherently nonlinear wall turbulence is explained by Landahl's theory of timescales, in that the linear control proceeds via the linear shear-interaction timescale which is significantly shorter than both the nonlinear and viscous timescales for turbulence. The linear shear-interaction timescale is effective as a result of the linear ("rapid") source term. The maximum control forcing is located at y⁺ ≈ 20, corresponding to the location of the maximum in the mean-square pressure gradient. The existence of Landahl's timescales in the near-wall region of the minimal flow unit at Re_cl = 5000 is confirmed. The dynamic mode decomposition (DMD) indicates that the linear operator is stable via the linear control. The application of DMD to nonlinear systems should be used with caution.
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Kong, Suyao. "Advanced passivity-based control for hybrid power systems : application to hybrid electric vehicles and microgrids." Thesis, Bourgogne Franche-Comté, 2020. http://indexation.univ-fcomte.fr/nuxeo/site/esupversions/a01b06c5-fb6c-452d-bd16-02b269cd0bb9.
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Un système hybride à base de pile à combustible (PàC) est une solution efficace pour faire face aux problèmes de pollution atmosphérique et de pénurie des combustibles fossiles. Cette thèse se concentre sur la conception de la commande pour les systèmes d'alimentation hybrides à base de PàC, et appliquée à deux applications : le véhicule électrique et le centre de données alimenté par un micro-réseau.Tout d'abord, cette thèse propose une commande basée sur la passivité pour un système hybride PàC/supercondensateurs (SCs). Cette commande a été conçue via la méthode de conception IDA-PBC (Interconnection and Damping Assignment - Passivity Based Control), afin de résoudre le problème de coordination des convertisseurs. L'état de charge des SCs ainsi que toutes les limitations sont intégrés directement dans la loi de commande. Un banc d'essais PHIL (Power Hardware-in-the-loop) est utilisé pour la validation. Ensuite, un filtre de Kalman étendu (EKF) est combiné avec la commande proposée, pour prévoir l'état de santé (SoH) de la pile à combustible. Enfin, un banc d'essais HIL (Hardware-in-the-loop) basé sur un FPGA INTEL / ALTERA est conçu afin de valider le fonctionnement des algorithmes en temps réel pour un véhicule commercial.Pour l'application à un micro-réseau, une commande passive est proposée pour un système hybride comprenant des panneaux photovoltaïques, une PàC, des SCs et un électrolyseur. La faisabilité de cette commande est validée par les résultats expérimentaux sur un banc d'essai PHIL. Ce travail est intégré au projet ANR DATAZERO.La nouveauté principale de cette commande est qu'elle intègre certaines contraintes de composants directement dans la loi de commande, en préservant la stabilité de l’ensemble du système, en boucle ferméeA Fuel cell (FC) hybrid power system is a promising solution to deal with the atmospheric pollution and fossil fuels shortage problems. This thesis focuses on the controller design for FC hybrid power systems, towards two applications: the hybrid electrical vehicle and the microgrid-powered datacenter.Firstly, this thesis proposes an advanced passivity-based control for a FC/super-capacitors (SCs) hybrid system. In order to solve the converters coordination problem, a controller designed using the design method Interconnection and Damping Assignment - Passivity-Based Control (IDA-PBC) is applied, which considers the state-of-charge of the SCs as well as voltage and current limitations. The proposed controller is validated on a Power Hardware-in-the-loop (PHIL) platform. Then an Extended Kalman Filter (EKF) is applied to forecast the State-of-Health (SoH) of the fuel cell and is combined with the proposed controller. Finally, a Hardware-in-the-loop (HIL) platform based on an INTEL/ALTERA FPGA is designed in order to validate the real-time operation of the algorithms for a specific case study with a commercial vehicle.For microgrid applications, a passivity-based controller for a hybrid power supply system for a green datacenter is proposed, including photovoltaic panels, a fuel cell, SCs and an electrolyzer. The feasibility of this non-linear controller is proven by the simulation results and experimental validation on a PHIL test bench. This work is integrated into the ANR DATAZERO project.The main novelty of the proposed controller is that it integrates some component constraints directly into the controller equations, while the locally asymptotic stability of the whole closed-loop system is preserved
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Dueñas, Diéz Marta. "Population balance modeling and passivity-based control of particulate processes, applied to the Silgrain® process." Doctoral thesis, Norwegian University of Science and Technology, Faculty of Information Technology, Mathematics and Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1944.
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This thesis deals with the systematic development of mechanistic models of particulate processes for the purposes of nonlinear controller design and implementation.The methods investigated in this thesis were illustrated with an industrial hydrometallurgical process called the Silgrain® process (Elkem ASA), for which a model and a controller strategy have been developed from scratch.
The class of processes studied in this thesis, particulate processes,has attracted and still attracts a great deal of interest from the international research community. Particulate processes are characterized by the presence of a continuous phase and a dispersed phase comprised of entities that have a distribution of properties. Such a distribution of properties has an important impact on the process operation and quality of the final products. Moreover, most of process industries contain one or more stages that involve particulate processes, among them the major Norwegian companies: Elkem, Hydro, Borealis, Statoil, etc.
A systematic method to PBE modeling was suggested, consisting of the following stages: establishment of model purpose and model foundations, building of the model structure, determination of the constitutive relations, selection of a solution method, parameter estimation and model validation. Such an approach is general to any type of process, but when dealing with particulate processes special care should be placed on some of these stages. The method was thoroughly illustrated with the development of the model of the tworeactors of the Silgrain® process. The model was based on the traditional balance equations of mass, energy, and momentum, and on a balance of the distribution of properties, called the population balance equation (PBE). This is the first time PBE is used to model a hydrometallurgical leaching reactor where disintegration takes place. An experimental laboratory campaign had to be carried out in order to determine the constitutive equations of the disintegration event. Another experimental campaign at the plant level was carried out to gather data for parameter estimation and model validation. The results of the fitting were satisfactory. Besides the particular contribution of developing a detailed model for the case study, some general contributions of this research were:
• it was shown how dividing the model into compartments according to the regions that are observed in practice in the reactors is key to obtaining realistic models;
• it was discussed how the widely used assumption of complete mixing provides unrealistic models. Instead, the compartmentalization approach combined with a balance of forces on the entities to define the interflows among compartments improves the realism of PBE models to a great extent;
• it was shown that the use of a systematic parameter identifiability analysis prior to parameter estimation can be very useful, and even essential. PBE models are large in size, typically nonlinear in the parameters, and many parameters may not be identifiable from theavailable measurements. Hence, if no parameter identifiability analysis is carried out, the parameter estimation algorithm may break down, or give very poor parameter estimates.
An approach to process control called inventory passivity-based control was selected in this thesis, since this method handles nonlinear processes, is based on dynamic models, and it has suitable stability properties. In order to apply this method to particulate processes, the theory was extended in this thesis to handle rectangular systems, i.e. systems where the number of available manipulated variables is less than the number of inventories. Both chemical reaction networks and particulate processes fall under such a class of systems. An stability proof has been developed, by linking inventory passivity-based control to a relevant theory of nonlinear chemical dynamics, called the Feinberg Deficiency Theorems. In addition to stability, some other implementation issues were discussed in the thesis, such as the handling of constraints on the manipulated variables, the robustness of the controller against disturbances and model errors, the importance of observers, and the adaptation of the approach to semibatch control. Finally, the thesis also discussed the role of inventory passivity-based control within the framework of plantwide control, and the integration of inventory passivity-based control with a statistical process monitoring approach.
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Hui, Xin. "Cascade Control of a Hydraulic Prosthetic Knee." Cleveland State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=csu1459772543.
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Kloiber, Tobias [Verfasser], Boris [Akademischer Betreuer] Lohmann, and Andreas [Akademischer Betreuer] Kugi. "Constructive Passivity-Based Control of Smooth and Switched Nonlinear Systems / Tobias Kloiber. Gutachter: Andreas Kugi ; Boris Lohmann. Betreuer: Boris Lohmann." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1072757915/34.
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Pirro, Matteo. "Embedded Control Systems for Performances Improvement and Energy Efficiency of Electrical Drives and Power Converters." Doctoral thesis, Università Politecnica delle Marche, 2015. http://hdl.handle.net/11566/243081.
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La domanda globale di energia elettrica è in continua crescita, al doppio del tasso di crescita del consumo di energia primaria. Un uso efficiente dell'energia, detto in altri termini "efficienza energetica", ha come obiettivo ridurre la quantità di energia richiesta per fornire i diversi prodotti e servizi.
Progressivamente diventerà obbligatoria per l'utente finale una sempre più chiara transizione dal combustibile primario verso sistemi di energia elettrica e l'efficienza energetica così come l'integrazione delle energie rinnovabili diventeranno una delle principali sfide del futuro. L'elettronica di potenza svolgerà un ruolo fondamentale nel cambiamento di questo paradigma. Nella generazione di energia elettrica vi sarà un importante migrazione alle fonti rinnovabili come future fonti energietiche. Nel campo dell'elettronica di potenza, quattro ambiti applicativi devono necessariamente essere presi in considerazione quando si parla di efficienza energetica: motori elettrici, convertitori di potenza, illuminazione a LED e HVDC.
In questa tesi è stata riportata una discussione dettagliata dei principali convertitori di potenza e sono state introdotte delle variazioni in alcuni modelli per rendere gli stessi più adatti alla rappresentazione del comportamento dei convertitori per particolari topologie o modalità di funzionamento.
Sono stati proposti e argomentati alcuni controllori basati su passività per la correzione del fattore di potenza; essi sono risultati particolarmente adatti a scenari applicativi come quello del controllo motori o dell'illuminazione a LED.
E' stato inoltre presentato un controllore PI basato su passività per il tracking globale valido per sistemi rappresentabili nella forma bilineare: particolarmente interessante è l'esempio applicativo riportato, relativo all'ambito del controllo HVDC.
Inoltre è stato elaborato un controllore sliding mode robusto alle variazioni di carico per la regolazione della tensione di uscita nei regolatori DC--DC.
Infine sono stati progettati degli osservatori di corrente per convertitori boost con l'obiettivo di rendere superfluo l'utilizzo dei costosi sensori di corrente in questa topologia.
Ciascun algoritmo è stato testato numericamente e la maggior parte di essi è stata anche implementata su piattaforme embedded e provata in laboratorio con l'obiettivo di verificarne e valutarne le prestazioni. Le prove sperimentali sono state effettuate nel Laboratorio di Robotica Avanzata del DII presso l'Università Politecnica delle Marche, Ancona, nel Laboratory of Energy Department presso il Supélec, Paris e nel Laboratoire de Signaux et Systémes presso il Supélec, Paris.The global demand for electrical energy is growing continuously, at double the growth rate of primary energy consumption. Efficient energy use, sometimes simply called energy efficiency, is the goal to reduce the amount of energy required to provide products and services. A clear transition to more electric energy systems is mandatory as energy efficiency from primary fuel to the enduser and the integration of renewables are the future key challenges. Power electronics will play a key role in this paradigm shift to more renewable electrical energy and higher energy efficiency in multiple applications. In electrical energy generation a major shift to renewables as sources of future electrical energy will happen. In the field of Power Electronics four topics must be taken into account talking about energy efficiency: electrical motors, power converters, LED lighting and HVDC. In this thesis a detailed discussion on the modelling of the most known power converters has been made and some more accurate models have been proposed to better represent the behaviour of particular topologies or working modes. Passivity-Based controllers for power factor control have been proposed and argued; they resulted particularly suited in the motor control and in the LED lighting applicative fields. A global tracking passivity–based PI controller for bilinear systems has been proposed: an example application has been presented in the field of HVDC control. Furthermore, a sliding-mode robust to load variations controller for output voltage regulation in DC--DC converters has been presented. Finally inductor current observers for the boost topology has been illustrated with the aim of making superfluous the use of expensive sensors in this topology. Each proposed algorithm has been numerically tested and many of them has been experimentally verified on embedded platforms and their performances evaluated. Experimental tests have been done in the Laboratory of Advanced Robotics of DII at Università Politecnica delle Marche, Ancona, in the Laboratory of Energy Department at Supélec, Paris and in the Laboratoire de Signaux et Systémes at Supélec, Paris.
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Benmouna, Amel. "Gestion énergétique reconfigurable d'un véhicule électrique basée sur l'identification en ligne des sources embarquées." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCA020.
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Ce sujet de thèse porte sur l’étude de la gestion énergétique reconfigurable d’un véhicule électrique basée sur l’identification en ligne des sources embarquées. Ces dernières années, la gestion d’énergie d’un système hybride pour les applications automobiles a fait l’objet d’un grand nombre de travaux de recherche. Dans cette étude, la chaine énergétique considérée se constitue d’une pile à combustible comme source principale, de sources de stockage à savoir les batteries et/ou les supercondensateurs, de convertisseurs pour chaque source et enfin d’une charge émulant la demande en puissance. En effet, le problème qui se pose dans les systèmes hybrides est de trouver une stratégie permettant une meilleure répartition de la puissance électrique entre les différentes sources embarquées, ce qui constitue l’apport de ce travail de recherche. Ainsi que de définir des lois de gestion énergétique en considérant des mesures faites en temps réel dans le but d’augmenter la durée de vie et la fiabilité des sources d’une part, et la disponibilité du véhicule électrique d’autre part. Dans ce travail de thèse, le contrôle non linéaire nommé IDA-PBC (Interconnection and Damping assignment-Passivity Based Control) est utilisé avec la structure PCH (Port Controlled Hamiltonian) qui permet de présenter des propriétés structurelles du système à savoir l'énergie totale du système, l'amortissement et les interconnexions d'états. La méthode IDA-PBC est une technique non linéaire puissante, elle est considérée comme un moyen général pour stabiliser une grande classe de systèmes physiques. Dans une seconde partie de ce travail, une stratégie de gestion de l'énergie optimale est proposée pour le système hybride étudié qui est la combinaison entre l’IDA-PBC et la méthode d’Hamiltonian Jacobi Bellman. La preuve de stabilité est donnée et l'efficacité de la stratégie proposée est démontrée. Plusieurs validations expérimentales valident ce travailThis thesis deals with the study of the reconfigurable energy management of an electric vehicle based on the online identification of embedded sources. In recent years, the energy management of a hybrid system for automotive applications has been the subject of a great number of research. In this study, the energy chain considered consists of a fuel cell as the main source, storage sources such as batteries and/or supercapacitors, converters for each source and finally a load emulating the power demand. Indeed, the problem in hybrid systems is to find a strategy for a better distribution of electrical power between the different embedded sources, which is the added value of this research work. As well as defining energy management laws by considering real-time measurements in order to increase the lifespan and reliability of sources on the one hand, and the availability of the electric vehicle on the other hand. In this thesis, the nonlinear control called IDA-PBC (Interconnection and Damping assignment-Passivity Based Control) is used with the PCH (Port Controlled Hamiltonian) structure which allows to present structural properties of the system namely total system energy, damping and state interconnections. The IDA-PBC method is a powerful nonlinear technique, it is considered as a general means to stabilize a large class of physical systems. In a second part of this work, an optimal energy management strategy is proposed for the hybrid system under study, which is the combination of IDA-PBC and Hamiltonian's Jacobi Bellman method. Proof of stability is provided and the effectiveness of the proposed strategy is demonstrated. Several experimental validations are presented
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Pang, Shengzhao. "Contribution to Stability Analysis and Stabilization of DC Microgrids : Application of the Concept of Passivity." Electronic Thesis or Diss., Université de Lorraine, 2020. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2020_0121_PANG.pdf.
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Cette thèse se concentre sur le problème de stabilité des micro-réseaux DC, en particulier dans les applications de transport électrifié. L'objectif principal de cette thèse est de résoudre les problèmes de stabilité et de trouver des améliorations liées à l'analyse de stabilité et à la stabilisation des micro-réseaux DC. Dans les applications considérées, la stabilité est toujours un critère clé dans la conception des micro-réseaux DC. Ces systèmes, constitués principalement de plusieurs convertisseurs et filtres LC en cascade et/ou en parallèle, peuvent souffrir d'instabilité, même si chacun des sous-systèmes est stable tout seul. De plus, les micro-réseaux DC dans les applications de transport électrifié peuvent avoir une structure variante dans le temps, avec des modes de fonctionnement très flexibles. En effet, les sources et les charges peuvent changer leurs modes de fonctionnement, ou même rejoindre ou quitter le micro-réseau de manière «plug-and-play». Cette caractéristique rend difficile la réalisation d'études de stabilité et requière un niveau d’exigence très élevé pour la conception des régulateurs. Pour tenter de résoudre ces problèmes, le concept de passivité est appliqué dans cette thèse. En fait, une étude générale de stabilité est proposée à l’aide de la théorie de la passivité qui garantit qu'un micro-réseau est stable tant que les conditions de passivité sont respectées par chacun de ses constituants et que l’interconnexion de ces derniers obéit à des conditions précises. De cette façon, l'objectif de stabilisation peut être traité au niveau des constituants du micro-réseau afin d’éviter d'investiguer l’ensemble du micro-réseau, fournissant ainsi une immunité contre les variations du système. Pour ce faire, une méthode de « Passivity-Based Control » (PBC), dite « Interconnection and Damping Assignment Passivity-Based Control » (IDA-PBC), est d'abord appliquée à deux convertisseurs DC/DC typiques. Cet objectif est atteint en concevant une matrice d'interconnexion adaptative pour établir des liaisons internes dans le modèle Hamiltonian du système, appelé « Port-Controlled Hamiltonian » (PCH) et pour générer une loi de commande unique. Ensuite, la stabilisation du micro-réseau DC est obtenue en développant un IDA-PBC modifié au niveau du sous-système. Les effets d'instabilité provoqués par le filtre LC, et également ceux provoqués par l'interaction entre les sous-systèmes sont pris en compte dans la conception du contrôleur. De plus, un observateur est ajouté au contrôleur PBC pour résoudre l'effet provoqué par les incertitudes des paramètres et du modèle. Par la suite, une stratégie de passivation est proposée pour stabiliser les micro-réseaux DC. Celle-ci est réalisée en développant un contrôleur PBC préservant la propriété de passivité du point de vue de l'interconnexion. Toute la théorie et les méthodes proposées peuvent garantir la stabilité du micro-réseau DC au sens large signal. En plus, les méthodes de contrôle proposées sont validées par des résultats extensifs de simulation, expérimentaux et Hardware-in-the-loop (HIL)This dissertation focuses on dealing with the stability issues of DC microgrids, especially in electrified transportation applications. The main objective of this dissertation is to solve problems and find improvements related to the stability analysis and stabilization of DC microgrids. In the applications under consideration, stability is still a key issue in the design of DC microgrids. These systems, mainly consisting of multiple cascaded and/or parallel converters and LC filters, can suffer from instability, even when individual converters are stable alone. Moreover, DC microgrids in electrified transportation applications may have a time-varying structure, with highly flexible subsystems and operating modes. Both sources and loads can switch their operation patterns, or even join or quit the microgrid in a plug-and-play manner. This feature makes it difficult to conduct the stability studies, and puts forward higher requirements for controller design. To consider the aforementioned issues, the concept of passivity is studied in this dissertation. Indeed, the general stability study is established using the passivity concept which ensures that a microgrid is stable as long as all its components meet the passivity conditions and are interconnected to each other under certain conditions. In this way, the stabilization objective is localized to avoid investigating the whole microgrid, thereby offering immunity against system variations. Initially, a branch of Passivity-Based Control (PBC), i.e. the Interconnection and Damping Assignment Passivity-Based Control (IDA-PBC), is applied to two typical DC/DC converters. This is achieved by designing an adaptive interconnection matrix to establish internal links in Port-Controlled Hamiltonian (PCH) models and to generate a unique control law. Then, the stabilization of DC microgrids is achieved by developing a modified IDA-PBC at the subsystem level. The instability effects caused by the LC filter, and also caused by the interaction between subsystems are taken into account in the controller design. Moreover, a nonlinear observer is added to the PBC controller to solve the effect caused by parameter and model uncertainties. Afterward, a passivation strategy is proposed to stabilize DC microgrids. This is achieved by developing a PBC controller that preserves the passivity property from the interconnection perspective. All the proposed PBC theory and estimation technology can guarantee the large-signal stability of the DC microgrid. In addition to these theoretical backgrounds, the proposed control methods are validated by extensive simulation, experimental, and Hardware-in-the-loop (HIL) results
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Cardoso-Ribeiro, Flávio Luiz. "Modélisation et commande d’interaction fluide-structure sous forme de système Hamiltonien à ports : Application au ballottement dans un réservoir en mouvement couplé à une structure flexible." Thesis, Toulouse, ISAE, 2016. http://www.theses.fr/2016ESAE0039/document.
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Cette thèse est motivée par un problème aéronautique: le ballottement du carburantdans des réservoirs d’ailes d’avion très flexibles. Les vibrations induites par le couplagedu fluide avec la structure peuvent conduire à des problèmes tels que l’inconfort des passagers,une manoeuvrabilité réduite, voire même provoquer un comportement instable. Cette thèse apour objectif de développer de nouveaux modèles d’interaction fluide-structure, en mettant enoeuvre la théorie des systèmes Hamiltoniens à ports d’interaction (pHs). Le formalisme pHsfournit d’une part un cadre unifié pour la description des systèmes multi-physiques complexeset d’autre part une approche modulaire pour l’interconnexion des sous-systèmes grâce auxports d’interaction. Cette thèse s’intéresse aussi à la conception de contrôleurs à partir desmodèles pHs. Des modèles pHs sont proposés pour les équations de ballottement du liquide en partantdes équations de Saint Venant en 1D et 2D. L’originalité du travail est de donner des modèlespHs pour le ballottement dans des réservoirs en mouvement. Les ports d’interaction sont utiliséspour coupler la dynamique du ballottement à la dynamique d’une poutre contrôlée par desactionneurs piézo-électriques, celle-ci étant préalablement modélisée sous forme pHs. Aprèsl’écriture des équations aux dérivées partielles dans le formalisme pHs, une approximation endimension finie est obtenue en utilisant une méthode pseudo-spectrale géométrique qui conservela structure pHs du modèle continu au niveau discret. La thèse propose plusieurs extensionsde la méthode pseudo-spectrale géométrique, permettant la discrétisation des systèmesavec des opérateurs différentiels du second ordre d’une part et avec un opérateur d’entrée nonborné d’autre part. Des essais expérimentaux ont été effectués sur une structure constituéed’une poutre liée à un réservoir afin d’assurer la validité du modèle pHs du ballottementdu liquide couplé à la poutre flexible, et de valider la méthode pseudo-spectrale de semi-discrétisation.Le modèle pHs a finalement été utilisé pour concevoir un contrôleur basé surla passivité pour réduire les vibrations du système coupléThis thesis is motivated by an aeronautical issue: the fuel sloshing in tanksof very flexible wings. The vibrations due to these coupled phenomena can lead to problemslike reduced passenger comfort and maneuverability, and even unstable behavior. Thisthesis aims at developing new models of fluid-structure interaction based on the theory ofport-Hamiltonian systems (pHs). The pHs formalism provides a unified framework for thedescription of complex multi-physics systems and a modular approach for the coupling ofsubsystems thanks to interconnection ports. Furthermore, the design of controllers using pHsmodels is also addressed. PHs models are proposed for the equations of liquid sloshing based on 1D and 2D SaintVenant equations and for the equations of structural dynamics. The originality of the workis to give pHs models of sloshing in moving containers. The interconnection ports are used tocouple the sloshing dynamics to the structural dynamics of a beam controlled by piezoelectricactuators. After writing the partial differential equations of the coupled system using thepHs formalism, a finite-dimensional approximation is obtained by using a geometric pseudospectralmethod that preserves the pHs structure of the infinite-dimensional model at thediscrete level. The thesis proposes several extensions of the geometric pseudo-spectral method,allowing the discretization of systems with second-order differential operators and with anunbounded input operator. Experimental tests on a structure made of a beam connected to atank were carried out to validate both the pHs model of liquid sloshing in moving containersand the pseudo-spectral semi-discretization method. The pHs model was finally used to designa passivity-based controller for reducing the vibrations of the coupled system
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Cisneros, Montoya Rafael. "Commande PI basée sur la passivité : application aux systèmes physiques." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS187/document.
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Le régulateur PID (Proportionnel-Intégral-Dérivée) est la commande par retour d'état la plus connue. Elle permet d'aborder un bon nombre de problèmes de commande, particulièrement pour des systèmes faiblement non linéaire et dont la performance requise est relativement modeste. En plus, en raison de sa simplicité, la commande PID est largement utilisée en l'industrie. Étant donnés que les méthodes de réglage de la commande PID sont basées sur la linéarisation, la synthèse d'un contrôleur autour d'un point d'équilibre est relativement simple, néanmoins, la performance sera faible dans des modes de fonctionnement loin du point d'équilibre. Pour surmonter ce désavantage, une pratique courante consiste en adapter les gains du PID, procédure connue sous le nom de séquencement de gain (ou gain-scheduling en anglais). Il y a plusieurs désavantages à cette procédure, comme la commutation des gains de la commande et la définition -non triviale- des régions de l'espace d'état dans lesquelles cette commutation aura lieu. Ces deux problèmes se compliquent quand la dynamique est fortement non linéaire. Dans d'autres méthodes, la synthèse de la commande utilise des schémas empiriques, ce qui ne permet pas l'analyse de la stabilité globale du processus. Dans ce contexte, ce travail de thèse a pour objectif de synthétiser des contrôleurs PI, basés sur la passivité, de telle sorte que la stabilité globale du système en boucle fermé soit garantie. L'un des avantages à utiliser la passivité est son attrait intuitif, qui exploite les propriétés physique des systèmes. L'idée centrale dans un système passive est que l'écoulement d'énergie entrante au système provenant de l'extérieur n'est pas inférieur à l'incrément de son énergie de stockage. Par conséquence, ces systèmes ne peuvent pas stocker plus d'énergie que celle fournie, dont la différence correspond à l'énergie dissipée. En introduisant le concept d'énergie, cette méthodologie nous permet de formuler le problème de commande en celui de trouver un système dynamique dont la fonction de stockage d'énergie prend la forme désirée. En incorporant le concept d'énergie cette méthode devient accessible à la communauté de praticiens et permets de fournir des interprétations physique de l'action de commande. Dans cette thèse, une méthodologie constructive de commande PI basée sur la passivité est présentée et motivée par des applications à des systèmes physiquesOne of the best known forms of feeding back a system is through a three-term control law called PID (Proportional-Integral-Derivative) controller. PID controllers are sufficient for many control problems, particularly when process dynamics are not highly nonlinear and the performance requirements are modest. Besides, because of its simple structure, the PID controller is the most adopted control scheme by industry and practitioners, beeing the PI the form mostly employed. Since the PI tuning methods are based on the linearization, commissioning a PI to operate around a single operating point is relatively easy, however, the performance will be below par in wide operating regimes. To overcome this drawback the current practice is to re-tune the gains of the PI controllers based on a linear model of the plant evaluated at various operating points, a procedure known as gain-scheduling. There are several disadvantages of gain-scheduling including the need to switch (or interpolate) the controller gains and the non-trivial definition of the regions in the plants state space where the switching takes place - both problems are exacerbated if the dynamics of the plant is highly nonlinear. In other common scenarios, a little information about the process dynamics or only a "good" linear approximation is taken into account when designing the control design. This impedes to analyse the global stability of the system. In this context, the current thesis work is aimed at the designing of PI controllers, based on the passivity theory, such that the stability of the closed-loop system is guarantied. One of the main advantages of passivity concepts is that they offer a physical and intuitive appeal. The primary idea in passive systems is that the power flowing into the system is not less that the increase of storage. Thus, they cannot store more energy than is supplied to it from the outside, with the difference being the dissipated energy. Thus, introducing the concept of energy, this methodology allows to recast the control problem as finding a dynamical system such that system energy function takes the desired form. Also, with this formulation, the communication between practitioners and control theorists is facilitated, incorporating prior knowledge of the system and providing physical interpretations of the control action. In this thesis, a constructive methodology for deriving PI passivity-based controllers is presented and motivated by the application to physical systems
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Jaafar, Ali. "Contribution à la modélisation, l'analyse et l'optimisation de lois de commande pour convertisseurs DC-DC de puissance." Phd thesis, Supélec, 2011. http://tel.archives-ouvertes.fr/tel-00644419.
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L'utilisation des convertisseurs de puissance pour des applications de la vie quotidienne devient de plus en plus importante. Les applications technologiques actuelles demandent simultanément un haut niveau de précision et de performance, ainsi les convertisseurs DC-DC ont un rôle très important dans les systèmes nécessitant la conversion et l'adaptation du niveau d'énergie. Nous nous intéressons dans le cadre des travaux de cette thèse à une analyse des approches de modélisation et de synthèse de loi de commande permettant d'assurer la stabilité et un certain niveau de performances dans l'ensemble du domaine de fonctionnement défini par un cahier des charges tout en prenant en compte la problématique de leur application dans un environnement industriel. L'objectif de nos travaux de recherche est donc de proposer des lois de commandes dont la synthèse est fondée sur une approche formalisé {modélisation + commande} en vue d'obtenir des lois de commande adaptées au point de fonctionnement. Les principes exploités sont fondés sur la commande et l'observation par modes glissants d'une part, et sur la théorie de passivité pour la synthèse des lois de commande, complétées par un couple {observateur d'état + estimateur de charge} dont la synthèse est fondée sur l'exploitation des principes d'immersion et invariance, d'autre part. Le souci de la validation expérimentale et de l'implantation des structures de commande avec du matériel disponible industriellement a été en permanence un fil conducteur. Pour démontrer l'efficacité des méthodes proposées, leur application expérimentale a été effectuée sur un convertisseur de type SEPIC. Ce convertisseur présente plusieurs avantages par rapport à autres convertisseurs. Cependant, il reste peu exploité, en dépit de ces avantages, en raison des difficultés pour obtenir des lois commande performantes permettant la stabilisation de sa tension de sortie dans tout l'ensemble du domaine de fonctionnement.
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Romero, Velázquez José Guadalupe. "Commande robuste par façonnement d’énergie de systèmes non-linéaires." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112019/document.
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Cette thèse porte sur la conception de commandes robustes pour les systèmes non linéaires, mettant l'accent sur les systèmes mécaniques. Des résultats concluants sont présentés pour résoudre deux situations très abordées dans la théorie du contrôle : 1) La stabilité des systèmes non linéaires perturbés ; 2) Le suivi global de trajectoire dans les systèmes mécaniques en ayant seulement connaissance de la position. Nous avons commencé par donner une méthode de conception des commandes robustes pour assurer une régulation de sortie non passive. En outre, si le système est perturbé (pas appariés), des preuves rigoureuses pour les rejeter sont fournies. Ce résultat est principalement inspiré d'un changement de coordonnées et de l'action intégrale dynamique. Si le scénario à traiter concerne des systèmes mécaniques avec des perturbations variant dans le temps, nous dotons le système de propriétés comme IISS (Integral Input- State Stable) et ISS (Input-State Stable). Ce résultat est obtenu en modifiant la procédure de conception de manière à rejeter les perturbations constantes (pas appariés). Cependant, en raison de la non-linéarité du système, les commandes qui en résultent ont une grande complexité. Pour le même problème, un deuxième et élégant résultat est donné au cas où un changement préalable de variable (impulsions) est réalisé. Finalement, une réponse convaincante au problème de suivi de trajectoire pour les systèmes mécaniques est donnée en tenant compte uniquement des informations de position. Nous résolvons ce problème en deux étapes. Premièrement, quelques modifications sont apportées à la preuve de stabilité d'un observateur de vitesse basée sur la théorie de l'invariance et l’Immersion récemment publié. Notez que ceci est un observateur satisfaisant la convergence exponentielle de vitesse dans les systèmes mécaniques. Deuxièmement et sur la base du changement de coordonnées (impulsions), un contrôleur de suivi avec stabilité exponentielle, tenant compte de la position et de la vitesse, est proposé. De telle sorte qu'avec la combinaison des deux résultats, le suivi de trajectoire exponentielle avec retour de position est donnéThis thesis focuses on the design of robust control for nonlinear systems, mainly on mechanical systems. The results presented are to two situations widely discussed in control theory: 1) The stability of nonlinear systems disturbed; 2) The global tracking trajectory in mechanical systems having only knowledge of the position. We started giving a design method of robust controls to ensure regulation on non-passive output. In addition, if the system is perturbed (constant unmatched), rigorous proof to its rejection is provided. This result is based mainly on change of coordinates and integral dynamic control. When the scenario to deal are mechanical systems with time-varying matched and unmatched, disturbance, the system is endowed with strong properties as IISS (Integral Input-State Stable) and ISS (Input-State Stable). This is achieved based on the design method to rejection of constant disturbances (unmatched). However, due to the nonlinearity of the system, the controllers have a high complexity. For the same problem, a second and elegant result is given making a initial change of coordinate on the momenta variable, such that the controller significantly simplifies, preserving the aforementioned robustness properties. Finally, a convincing answer to the problem of global exponential tracking of mechanical systems is given taking into account only the position information. We solve this problem in two steps. First, some slight variation is presented to the proof of stability of a speed observer based on Immersion and Invariance theory recently published. Note that this is a speed observer satisfying the exponential convergence speed in mechanical systems. Secondly, and based on the change of coordinates (momenta), a globally exponentially stable tracking controller with position and velocity known is proposed. The combination of both results give the first global exponential tracking controller of mechanical systems without velocity measurements
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Machado, Martínez Juan Eduardo. "Some Problems on the Analysis and Control of Electrical Networks with Constant Power Loads On Existence of Equilibria of Multi-Port Linear AC Networks With Constant-Power Loads An Adaptive Passivity-Based Controller of a Buck-Boost Converter with a Constant Power Load Power-Controlled Hamiltonian Systems: Application Electrical Systems with Constant Power Loads On the Existence and Long-Term Stability of Voltage Equilibria in Power Systems with Constant Power Loads Active Damping of a DC Network with a Constant Power Load: An Adaptive Observer-based Design." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS445.
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La croissante demande d'énergie électrique a conduit à la conception de systèmes électriques de grande complexité où les combustibles fossiles constituent la principale source d'énergie. Néanmoins, les préoccupations environnementales poussent à un changement majeur dans les pratiques de production d'électricité, avec un passage marqué des énergies fossiles aux énergies renouvelables et des architectures centralisées à distribuées. Les problèmes de stabilité dus à la présence de ce qu'on appelle les Charges à Puissance Constante (CPLs) constituent l’un des principaux défis auxquels sont confrontés les systèmes électriques distribués. On sait que ces charges, que l’on trouve couramment dans les installations de technologie de l’information et de la communication, réduisent l’amortissement effectif des circuits qui les alimentent, ce qui peut provoquer des oscillations de tension, voire une chute. Dans cette thèse, les principales contributions sont centrées sur la compréhension et la résolution de divers problèmes rencontrés dans l'analyse et le contrôle de systèmes électriques contenant des CPLs. Les contributions sont énumérées comme suit. (i) Des conditions simplement vérifiables sont proposées pour certifier la non existence d'états en régime permanent pour des réseaux multi-ports, à courant alternatif avec une distribution de CPLs. Ces conditions, qui reposent sur les inégalités matricielles linéaires, permettent d’écarter les valeurs des puissances des charges qui produiraient certainement un effondrement de la tension sur l’ensemble du réseau. (ii) Pour des modèles généraux de certains systèmes électriques modernes, y compris les réseaux de transmission à courant continu haute tension et les microréseaux, il est montré que, si des équilibres existent, il existe un équilibre caractéristique à haute tension qui domine tous les autres. En outre, dans le cas des systèmes d'alimentation en courant alternatif sous l'hypothèse de découplage standard, cet équilibre caractéristique s'avère stable à long terme. (iii) Une classe de systèmes port-Hamiltoniens, dans laquelle les variables de contrôle agissent directement sur l'équation du balance de puissance, est explorée. Il est démontré que ces systèmes sont décalés de manière passive lorsque leurs trajectoires sont contraintes à des ensembles facilement définissables. Ces dernières propriétés sont exploitées pour analyser la stabilité de leurs équilibres intrinsèquement non nuls. Il a également été montré que la stabilité des réseaux électriques à courant continu multiports et des générateurs synchrones, tous deux connectés à des CPLs, peuvent naturellement être étudiée avec le cadre proposé. (iv) Le problème de la régulation de la tension de sortie du convertisseur buck-boost alimentant une CPL non connu est résolu. L'un des principaux obstacles à la conception de commandes linéaires classiques provient du fait que le modèle du système est de phase non minimale par rapport à chacune de ses variables d'état. Cette thèse rapporte un contrôleur adaptatif non linéaire capable de rendre un équilibre souhaité asymptotiquement stable; de plus, une estimation de la région d'attraction peut être calculée. (v) La dernière contribution concerne l'amortissement actif d'un système d'alimentation de petite taille à courant continu avec une CPL. Au lieu de connecter des éléments passifs peu pratiques et énergétiquement inefficaces au réseau existant, l’ajout d’un convertisseur de puissance contrôlé est exploré. La contribution principale rapportée ici est la conception d'une loi de contrôle non linéaire basée sur l'observateur pour le convertisseur. La nouveauté de la proposition réside dans le fait qu'il n'est pas nécessaire de mesurer le courant électrique du réseau ni la valeur de la CPL, soulignant ainsi son applicabilité pratique. L'efficacité du schéma de contrôle est ensuite validée par des expériences sur un réseau à courant continu réelThe continuously increasing demand of electrical energy has led to the conception of power systems of great complexity that may extend even through entire countries. In the vast majority of large-scale power systems the main primary source of energy are fossil fuels. Nonetheless, environmental concerns are pushing a major change in electric energy production practices, with a marked shift from fossil fuels to renewables and from centralized architectures to more distributed ones. One of the main challenges that distributed power systems face are the stability problems arising from the presence of the so-called Constant Power Loads (CPLs). These loads, which are commonly found in information and communication technology facilities, are known to reduce the effective damping of the circuits that energize them, which can cause voltage oscillations or even voltage collapse. In this thesis, the main contributions are focused in understanding and solving diverse problems found in the analysis and control of electrical power systems containing CPLs. The contributions are listed as follows. (i) Simply verifiable conditions are proposed to certify the non existence of steady states in general, multi-port, alternating current (AC) networks with a distributed array of CPLs. These conditions, which are based on Linear Matrix Inequalities, allow to discard the values of the loads' powers that would certainly produce a voltage collapse in the whole network. (ii) For general models of some modern power systems, including High-Voltage Direct Current transmission networks and microgrids, it is shown that if equilibria exist, then there is a characteristic high-voltage equilibrium that dominates, entry-wise, all the other ones. Furthermore, for the case of AC power systems under the standard decoupling assumption, this characteristic equilibrium is shown to be long-term stable. (iii) A class of port-Hamiltonian systems, in which the control variables act directly on the power balance equation, is explored. These systems are shown to be shifted passive when their trajectories are constrained to easily definable sets. The latter properties are exploited to analyze the stability of their---intrinsically non zero---equilibria. It is also shown that the stability of multi-port DC electrical networks and synchronous generators, both with CPLs, can be naturally studied with the proposed framework. (iv) The problem of regulating the output voltage of the versatile DC buck-boost converter feeding an {em unknown} CPL is addressed. One of the main obstacles for conventional linear control design stems from the fact that the system's model is non-minimum phase with respect to each of its state variables. As a possible solution to this problem, this thesis reports a nonlinear, adaptive controller that is able to render a desired equilibrium asymptotically stable; furthermore an estimate of the region of attraction can be computed. (v) The last contribution concerns the active damping of a DC small-scale power system with a CPL. Instead of connecting impractical, energetically inefficient passive elements to the existing network, the addition of a controlled DC-DC power converter is explored. The main contribution reported here is the design of a nonlinear, observer-based control law for the converter. The novelty of the proposal lies in the non necessity of measuring the network's electrical current nor the value of the CPL, highlighting its practical applicability. The effectiveness of the control scheme is further validated through experiments on a real DC network
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Khanchoul, Mohamed. "Contribution au développement de la partie électromécanique d’un compresseur pour climatisation de véhicule électrique." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112384/document.
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Cette thèse s'inscrit dans le cadre du projet Compacité qui vise à développer un compresseur électrique pour véhicules électriques à l’aide d’une démarche mécatronique. Dans cette thématique, le rôle du LGEP est de développer la partie électromécanique du compresseur. Cette thèse est constituée de deux parties, la première concerne la conception d’un moteur pour le compresseur et la deuxième a trait à la commande sans capteur mécanique de ce moteur. La première partie de la thèse est d'abord consacrée au dimensionnement d'une machine électrique pour un compresseur électrique. Le cahier des charges impose une machine compacte (97mm de diamètre et une profondeur inférieure à 50mm) et ayant une puissance massique élevée (6kW pour une masse de 1.8kg). Au préalable, un modèle analytique a été développé pour effectuer un dimensionnement rapide. Par la suite, la méthode des éléments finis a été appliquée à différents modèles physiques (magnétique, thermique, mécanique (résistance des matériaux et vibration)) pour une étude approfondie de la structure choisie. A l'issue de ces études, un prototype et un banc expérimental ont été réalisés. Dans un second temps, des algorithmes de commande avec ou sans capteur mécanique ont été étudiés pour le pilotage du moteur. La particularité de cette deuxième partie de thèse est la réalisation d'une commande peu gourmande en temps de calcul et implantable dans des microcontrôleurs de faibles performances. A l'issue de cette partie, une nouvelle loi de commande appelée commande passive échantillonnée ainsi qu'un observateur adaptatif étendu (observateur fondé sur l'estimation des fem) ont été développés et testés sur un banc expérimentalThis thesis is part of the project Compacite which aims to develop an electric compressor for electrical vehicles using a mechatronic approach. In this way, the LGEP contribution is to develop the electromechanical part of the compressor.The document is divided in two parts: the first one is related to the design of the motor and the second part is dedicated to the sensorless control.In the first part, the electromagnetic design is proposed to comply with the industrial constraints according to the compressor operation. The specifications require a compact motor (external diameter equal to 97 mm and an active depth less than 50 mm) and a good power/mass ratio (6 kW for a weight of 1.8 kg). At first the design is based on an analytical model in order to obtain a fast sizing. Thereafter the finite element method is used for multiphysical studies (magnetic, thermal and mechanical (in terms of strength of materials and vibration)). A prototype is built and characterized on a test bench. In the second part, some algorithmic control laws have been developed with sensor and sensorless control. In this part a particular control law (sampled data passivity based control) with a low algorithmic cost has been developed for driven the motor and has been validated on the test bench. At the end an observer based on the estimation of the electromotive force is used for sensorless control and validated on the test bench
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Ramirez, Rivera Victor Manuel. "Energy management of lossy multi-port to fuel cell-based systems." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112087/document.
Full textAbstract:
Dans de nombreux réseaux, la régulation efficace du transfert d'énergie entre les sous-systèmes de production, de stockage et d'utilisation demeure un sujet difficile à traiter. Dans cette thèse on a proposent une nouvelle stratégie pour atteindre cet objectif, ainsi que sa mise en œuvre. Le dispositif est appelé routeur d'énergie dynamique (RED), parce que, contrairement à la pratique actuelle, l'asservissement de l'écoulement de puissance se fait sans s'appuyer sur des hypothèses stationnaire. Une hypothèse clé pour le bon fonctionnement du RED est que la dissipation du système est négligeable. Toutefois, en présence de pertes en ligne le RED initial n'est plus opérationnel, car il est base sur l'hypothèse clé de non dissipation des interconnections. Dans ce travail, un nouveau RED prenant en compte la présence de pertes est proposé. Des preuves de l'amélioration des performances sont présentées en simulation comme en expérimentation. Un complément de ce travail a été réalisée sur l'estimation des paramètres d'une pile à combustible du type Polymer Exchange Membrane (PEM) dans le but de concevoir un estimateur convergeant sur un grand domaine (convergence globale). Ce dernier utilise des principes d'immersion et d'invariance développés récemment dans la théorie des asservissementsEfficient regulation of the energy transfer between generating, storage and load subsystems is a topic of current practical interest. A new strategy to achieve this objective, together with its corresponding power electronics implementation, was recently proposed in this thesis work. The device is called dynamic energy router (DER) because, in contrast with current practice, the regulation of the direction and rate of change of the power flow is done without relying on steady–state considerations. A key assumption for the correct operation of the DER is that dissipation in the system is negligible. Unfortunately, in the presence of dissipation the original DER ceases to be operational. In this thesis a new DER that takes into account the presence of losses is proposed. Simulation and experimental evidence of the performance improvement with the new DER are presented. As a complement of this work a global convergent estimator of parameters of Polymer Exchange Membrane Fuel Cell (PEMFC) was designing by using the principles or “Immersion and Invariance” recently reported in control theory
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Croci, Lila. "Gestion de l'énergie dans un système multi-sources photovoltaïque et éolien avec stockage hybride batteries/supercondensateurs." Phd thesis, Université de Poitiers, 2013. http://tel.archives-ouvertes.fr/tel-00943296.
Full textAbstract:
Ce mémoire présente le travail de recherche effectué pour la conception d'une stratégie de commande originale, destinée aux systèmes de puissance hybrides en sites isolés. Le système considéré, voué à l'alimentation électrique d'une habitation, comprend deux sources, un groupe de panneaux photovoltaïques et une petite éolienne, et deux types de stockage, un banc de batteries lithium-ion et un de supercondensateurs. Face au problème de gestion de l'énergie dans un système hybride, et aux enjeux de maximisation de sa puissance produite, nous proposons de développer une stratégie de commande basée sur les flux d'énergie. pour cela, nous présentons dans un premier temps les modélisations d'Euler-Lagrange et hamiltonienne du système. Ces modèles permettent d'utiliser la propriété de passivité de celui-ci, et ainsi de synthétiser des commandes par injection d'amortissement pour chaque source, afin de maximiser sa production, et pour les supercondensateurs, dans le but d'assurer une répartition cohérente des flux d'énergie entre eux et les batteries. Les commandes sont finalement mises en œuvre dans un simulateur, puis dans un banc d'essai expérimental, afin d'une part de comparer leurs performances à celles de solutions préexistantes, et d'autre part de valider le bon fonctionnement du système hybride complet les utilisant.
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Yu, Yuan-Yi, and 余遠義. "Adaptive Control and Passivity Based Control for Linear Induction Motors." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/01795977112041860932.
Full textAbstract:
碩士中原大學
電機工程研究所
89
A linear induction motor (LIM) is a kind of special electrical machines that convert electrical energy directly into mechanical energy of linear motion. Owing to the nonlinear, time-varying, coupled model of LIM, the speed control becomes a complex problem. A challenge arises on the modeling and controller design of LIM due to the existence of the end effect. The aim of this thesis is to derive the mathematical model of an LIM where the end effect is considered, and then two schemes,namely adaptive control and passivity based control (PBC), are proposed to design the LIM speed controller. Form the circuit and energy point of view, the mathematical model of an LIM can be derived based on Kirchhoff’s voltage law and Euler-Lagrange equations, respectively. An LIM can be regarded as an unrolled rotary motor by cutting the rotary motor along a radial plane. Hence, the structure is similar to the induction motor. However, when we model the LIM, the end effect should be emphasized. When the primary of an LIM moves, the secondary under the edge of primary will create the eddy current to resist a sudden increasing or disappearing fluxes. After modelling the end effect due to eddy current, we obtain the complete mathematical model of an LIM. Based on the two forms of the derived models, adaptive control and passivity based control(PBC) are, respectively, proposed to design the LIM speed controller. LIM is an electromechanical system and can be decomposed into a mechanical subsystem and an electrical subsystem. Therefore, a two-stage control design, namely torque controller and speed controller are developed. An adaptive controller with a nonexplicit flux observer is applied to handle the speed tracking problem when the mechanical parameters and the flux of secondary are unknown. The PBC design includes two main parts, namely damping injection and energy shapping to form the controller. Lyapunov direct method is used to analyize the stability of the closed-loop systems. Finally, numerical simulation and hardware experiments are carried out to verify the performance of the proposed controller.
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Hoeffner, Kai. "Geometric Aspects of Interconnection and Damping Assignment - Passivity-Based Control." Thesis, 2011. http://hdl.handle.net/1974/6297.
Full textAbstract:
This dissertation deals with smooth feedback stabilization of control-affine systems via Interconnection and Damping Assignment - Passivity-Based Control (IDA-PBC). The IDA-PBC methodology is a feedback control design technique that aims to establish or manipulate a port-Hamiltonian structure of the closed-loop system.
For a mechanical control system, a port-Hamiltonian system is a natural description of the dynamics, and several effective controller designs have been presented for this class of systems. In other fields of engineering, the development of such controller design is an active area of research. In particular, applications of IDA-PBC techniques prove to be difficult in practice for process control applications where the concept of energy is usually ill-defined.
This thesis seeks to extend the application of the IDA-PBC methodology beyond mechanical control systems. This is achieved by following three directions of research.
First, we establish conditions under which a port-Hamiltonian system can be written as a feedback interconnection of two port-Hamiltonian system. We identify such an interconnection structure for linear control systems based on their intrinsic properties.
Second, as observed in application of IDA-PBC to non-mechanical systems, several additional assumptions on the structure of the desired port-Hamiltonian system can effectively reduce the complexity of the matching problem. We establish a unified approach that considers these additional assumptions. Third, we connect the matching problem to the classical feedback equivalence approach. We show that feedback equivalence between control-affine systems can be employed to construct some feasible interconnection and damping structures.Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2011-01-31 12:59:56.828
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Teo, Yik Ren. "Passivity-Based Control of a class of Underactuated Robotic System." Thesis, 2013. http://hdl.handle.net/1959.13/1039266.
Full textAbstract:
Masters Research - Master of Philosophy (MPhil)The control problem investigated in this thesis is motivated by the desire to use standard off-the-shelf robotics combined with advanced motion control for aerospace automated manufacturing. Aerospace manufacturing is characterised by a low production rate, tight tolerances, and production of large components. These unique characteristics have led to the use of custom made robotic manipulators for automated manufacturing. Such robots are expensive and hard to maintain. Hence, the combination of standard off-the-shelf robots with advanced control is an attractive alternative for some applications. The use of the lighter robots brings the problem of undesired vibrations, which can affect the required tolerances. These vibrations appear in components of the robotic system, which are not actuated; and thus, the control problem result in that of an underactuated mechanical system. Since robot motion follows the physical laws of mechanics, motion control designs based on energy-related properties like passivity and dissipativity have been very successful. Passive systems are a class of dynamic systems in which a magnitude akin to energy is exchanged between the system and its environment, and the rate at which this magnitude is exchanged is not less than the increase of its storage in the system. When the systems under study are physical, passivity relates to the exchange of energy; thus, physical passive systems can never store more energy than that supplied by the environment, and under certain conditions passivity ensures stability. The analogy to magnitudes akin to energy allows one to use a powerful set of mathematical tools related to physical phenomena for designing control systems in different areas of science and technology. We consider an idealised physical system representative of a class of robotic systems that has a robotic manipulator mounted on a base that can vibrate due to the motion of the robotic manipulator. The base is assumed to be unactuated. We derive a Port- Hamiltonian System (PHS) model. The important property of PHS models is that of passivity, which leads to stability. This characteristic of PHS models has been exploited to develop different energy-based control techniques. In this project, we explore the use of a control design technique called Interconnection and Damping Assignment Passivity Based Control (IDA-PBC). This strategy seeks to design a controller that shapes the energy of the system through its interconnection and injects damping so that the closedloop system results in a PHS. With such closed-loop system, the closed-loop Hamiltonian can be used as natural Lyapunov function to demonstrate stability. We addressed the problem in different stages. We first consider the problem of set point regulation for the end effector of the robot. Then we extend the problem to incorporate integral action to increase robustness to slowly-varying disturbances using dynamic extension. Finally, we consider the problem of trajectory tracking with and without integral action. This thesis is the result of research collaboration between Boeing Research & Technology Australia and the University of Newcastle. The idealised physical system considered in the thesis is motivated by a SCARA-Tau parallel kinematic robot manipulator. The particular task envisaged for this robot requires the robot to be mounted such that the axis of rotation is horizontal. Such configuration results in a non-axial gravity field, and as the robot moves, a heavy tool it is expected to excite some of the resonant modes of both the robot and base on which the robot is mounted. The results obtained for the idealised physical model in terms of accuracy of tool motion show a significant performance improvement with respect to other techniques proposed in the literature. Furthermore, through the addition of integral action the system is able to deal with constant external disturbances and provide robustness to modelling uncertainty. The addition of integral action and the design of tracking controllers for underactuated mechanical system in the Port-Hamiltonian framework has not been developed in the literature. Hence, this is a significant contribution to the field.
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Pfister, Matthias Lambeck Steven. "Analysis and control of a biomechanical system using the passivity based approach /." 2006. http://www.gbv.de/dms/ilmenau/abs/527940089pfist.txt.
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Chen, Jenn-Yih, and 陳進益. "Passivity-Based Position Control and Rotor Resistance Estimation for an Induction Motor." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/72324371792739352569.
Full textAbstract:
博士國立臺灣科技大學
電機工程系
90
This dissertation presents passivity-based adaptive control and sliding mode control schemes for the position control of an induction motor. First, the mathematical model of the induction motor in the synchronously rotating reference frame is derived from the three-phase circuit via the coordinate transformation. There is no need to design a rotor flux observer when the electrical parameters of the induction motor are known. The dynamics of the induction motor and the position controllers are analyzed to be passive by the passivity theorem. Furthermore, one can also design a rotor resistance observer and a sliding mode controller to estimate the rotor resistance and control the position of the induction motor. First, the input-output linearization theory is employed to decouple the rotor position and the flux amplitude in the rotor reference frame. Then, a flux observer is adopted to estimate the rotor flux. The passive properties of the rotor resistance observer with the flux observer and the sliding mode position controller are analyzed by the passivity theorem. The stability analysis of the overall position control system is carried out by using the passivity theorem instead of Lyapunov-type arguments. Finally, the C language is used to implement the proposed control algorithm on a PC-based controller, and applied to a three-phase induction motor for the position control purpose. Experimental results are provided to show good position response and fast convergent speed of the estimated parameters for the composite adaptive controller. The proposed sliding mode position controller with an adaptive law is valid for eliminating the chattering effects associated with a conventional sliding mode position controller. When the rotor resistance is varied with the temperature, the proposed rotor resistance observer with a sliding mode controller are effective in estimating the rotor resistance, load torque disturbances and tracking the rotor position.
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Yeh, Ying-Jyh, and 葉映志. "Passivity-Based Speed Control for Induction Motor Drives with Dead-Time Compensation." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/82057536837207309651.
Full textAbstract:
碩士國立成功大學
工程科學系
87
Abstract Owing to the inherent nonlinearity of induction motors, the speed control becomes a challenging problem because the rotor electrical variables such as rotor fluxes and currents are usually unavailable for measurements, and the motor parameters are varying significantly from their nominal values. Based on passivity, the main goal of the dissertation is to design a speed tracking controller for an induction motor drive without knowledge of the electrical rotor variables. Passivity based control (PBC) was proposed by Espinosa and Ortega. From an energy point of view, the dynamics of an induction motor can be described by Euler-Lagrange equations of motion. The controlled induction motor is composed of electrical and mechanical subsystems. The nonlinear damping can be injected to the electrical subsystem to enhance its stability margin. Then the inner loop current controller and the outer loop speed controller are designed. The former uses energy shaping technique, and the latter is aimed to change the dominant time constant for the mechanical subsystem by adding a first order low pass filter. Furthermore, passivity-based control exactly reduces to the well-known indirect field-oriented control by adaptive hysteresis current control. It provides a solid theoretical foundation to this popular control strategy. In the inverter of the driver, the time delay is usually added to the switching signals to prevent a short circuit occurring in the dc link. This causes the dead-time effect which is detrimental to the performance of inverters. To overcome this drawback, a dead-time compensation method in the SPWM inverter is proposed in this dissertation. The whole induction motor speed control system is implemented by using a high-speed digital signal processor, and an induction motor of one horsepower with a motor driver. The simulation and experiment results of two kinds of controllers are compared under various load disturbances and rotor resistances.
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Stacey, Geoff. "Sensor-based formation control using a generalised rigidity framework and passivity techniques." Phd thesis, 2016. http://hdl.handle.net/1885/117037.
Full textAbstract:
The research in this thesis addresses the subject of sensor-based
formation control for a network of autonomous agents.
The task of formation control involves the stabilisation of the
agents to a desired set of relative states, with the possible
additional objective of manoeuvring the agents while maintaining
this formation.
Although the formation control challenge has been widely studied
in the literature, many existing control strategies are based on
full state information, and give little consideration to the
sensor modalities available for the task.
The focus of this thesis lies in the use of a generic arrangement
of partial state measurements as can commonly be acquired by
onboard sensors; for example, time-of-flight sensors can be used
to measure the distances between vehicles, and onboard cameras
can provide the bearing from one vehicle to each of the others.
Particular aspects of the problem that are addressed in this
thesis include (i) ways of modelling the formation control task,
(ii) methods of analysing the system's behaviour, and (iii) the
design of a formation control scheme based on generic
arrangements of sensors that provide only partial position
information.
A key contribution in this thesis is a generalisation of the
classical notion of rigidity, which considers the use of distance
constraints between agents in R^2 or R^3 to specify a rigid body
(or formation).
This enables the concept of rigidity to be applied to agent
networks involving a variety of (possibly non-Euclidean)
state-spaces, with a generic set of state constraints that may,
for example, include bearings between agents as well as
distances.
I demonstrate that this framework is very well-suited for
modelling a wide variety of formation control problems
(addressing goal (i) above), and I extend several fundamental
results from classical rigidity theory in order to provide
significant insight for system analysis (addressing goal (ii)
above).
To design a formation control scheme that uses generic partial
position measurements (addressing goal (iii) above), I employ a
modular passivity-based approach that is developed using the
bondgraph modelling formalism.
I illustrate how adaptive compensation can be incorporated into
this design approach in order to account for the unknown position
information that is not available from the onboard sensors.
Although formation control is the subject of this thesis, it
should be noted that the rigidity-based and passivity-based
frameworks developed here are quite general and may be applied to
a wide range of other problems.
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Seng-MingPuah and 潘辰銘. "Passivity-Based Control for Networked Robotic System with Time Delay and Packet Loss." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/32570063410682127779.
Full textAbstract:
碩士國立成功大學
機械工程學系
102
Robotic control systems have been extensively applied in industrial operation, underwater navigation, and outer space exploration. With the rapid development of Internet, traditional robotic systems with wired connection are increasingly replaced by systems in which the robotic system and controller are connected through a communication network. Control of robotic system over communication network provides many advantage, but the signal transmission cannot be regarded as ideal, and network uncertainties time delay, packet loss, and limited communication resources constitute major challenges. The objective of this study is to develop a control algorithm for network of robotic systems achieve position regulation in the presence of communication delay and packet loss. This thesis studies the control problem of networked robotic system by utilizing passivity approach. Wave-Variable Transformation is combined with Wave-Variable Modulation to deal with networked robotic systems under time-constant delay and packet loss. Based on passivity control theory, robotic system is passive with respect to velocity and torque as the input-output pair. Therefore the remote controller works out with the position information by integrating the velocity information. The issue of position drift would degrade performance of a robotic system due to the lack of position information in remote controller. In this thesis, a Local Controller is presented to transmit a signal containing both velocity and position information. Therefore, the position regulation can be guaranteed without the requirement of explicit position signals. Due to the discrete-time nature of communication network, the proposed control framework is extended to discrete-time system. A passive sampler and hold is used to convert the continuous-time signal form the robotic system to a discrete-time signal, and vice versa. Finally, the efficiency of the developed networked robotic system is validated via both simulation and experiment results.
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Rakhsha, Ramtin. "Scalable Distributed Networked Haptic Cooperation." Thesis, 2015. http://hdl.handle.net/1828/6006.
Full textAbstract:
In cooperative networked haptic systems, some distributed distant users may decide to leave or join the cooperation while other users continue to manipulate the shared virtual object (SVO). Cooperative haptic systems that support interaction among a variable number of users, called scalable haptic cooperation systems herein, are the focus of this research. In this thesis, we develop distributed control strategies that provide stable and realistic force feedback to a varying number of users manipulating a SVO when connected across a computer network with imperfections (such as limited packet update rate, delay, jitter, and packet-loss). We fi rst propose the average position (AP) scheme to upper bound the effective stiff ness of the SVO coordination and thus, to enhance the stability of the distributed multi-user haptic cooperation. For constant and small communication delays and over power-domain communications, the effectiveness of the proposed AP paradigm is compared with the traditional proportional-derivative (PD) scheme via multi-rate stability and performance analyses supported with experimental verif cations.
Next, in a passivity-based approach, the scalability is pursued by implementing the AP scheme over wave-domain communication channels along with passive simulation of the dynamics. By constructing a passive distributed SVO in closed-loop with passive human users and haptic devices, we guarantee the stability of the distributed haptic cooperation system. However, energy leak at joining/leaving instances may compromise the passivity of the SVO. We examine the preservation of passivity of the proposed SVO scheme for such situations. A switching algorithm is then introduced in order to improve the performance of the cooperative haptic system. Experiments in which three users take turn in leaving or joining the cooperation over a network with varying delay and packet-loss will support the theoretical results.Graduate
0771
0548
0537
0544
rrakhsha@uvic.ca
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Huang, Kuang-Li, and 黃光立. "PDE Model-based Stable Control Design and Implementation for a Planar Two-link Flexible Manipulator via Passivity Principle." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/97138771843628540876.
Full textAbstract:
碩士國立中興大學
機械工程學系所
94
In this thesis, we first derived a simplified exact dynamic model for a planar two-link flexible manipulator using system’s free body diagram’s. Considering this simplified exact dynamic model, a proper Lyapunov function candidate is selected. Then a stable controller, including bending moment and shear force feedback, is derived using Lyapunov stability theory. The bending moment and shear force signals for of feedback control are obtained using strain gages. Finally, controller implementation studies using a dSPACE DS1103 single-board controller are presented to illustrate the effectiveness of the suggested control strategy.
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MORESCHINI, ALESSIO. "Modeling and control of discrete-time and sampled-data port-Hamiltonian systems." Doctoral thesis, 2021. http://hdl.handle.net/11573/1550161.
Full textAbstract:
Modeling and control of port-Hamiltonian systems are extensively studied in the continuous-time literature as powerful tools for network modeling and control of complex physical systems. Since controllers are unavoidably implemented through digital devices, accurate sampled-data models and control strategies are highly recommended to prevent a negative impact on the closed-loop performances under digital control. This thesis contributes to the description of new port-Hamiltonian structures both in a purely discrete-time and sampled-data framework. Then, on these bases, stabilizing and energy-based digital feedback strategies are developed. Regarding modeling, the proposed state-space forms make use of the concepts of Difference/Differential Representation (DDR) of discrete-time dynamics and the discrete gradient function. The proposed models exhibit a Dirac structure that properly defines the storing, resistive and external elements of the concerned port-Hamiltonian system. For stabilization purposes, the u-average passivity property has been essential for properly discussing passivity-based-control (PBC) strategies such as damping output feedback and Interconnection and Damping Assignment (IDA-PBC) both in discrete time and under sampling. Three case studies from different physical domains aim to illustrate the computational aspects related to the modeling and control design and further we validate their performances by means of simulations.
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Forbes, James Richard. "Extensions of Input-output Stability Theory and the Control of Aerospace Systems." Thesis, 2011. http://hdl.handle.net/1807/31751.
Full textAbstract:
This thesis is concerned with input-output stability theory. Within this framework, it is of interest how inputs map to outputs through an operator that represents a system to be controlled or the controller itself. The Small Gain, Passivity, and Conic Sector Stability Theorems can be used to assess the stability of a negative feedback interconnection involving two systems that each have specific input-output properties.
Our first contribution concerns characterization of the input-output properties of linear time-varying (LTV) systems. We present various theorems that ensure that a LTV system has finite gain, is passive, or is conic. We also consider the stability of various negative feedback interconnections.
Motivated by the robust nature of passivity-based control, we consider how to overcome passivity violations. This investigation leads to the hybrid conic systems framework whereby systems are described in terms of multiple conic bounds over different operating ranges. A special case relevant to systems that experience a passivity violation is the hybrid passive/finite gain framework. Sufficient conditions are derived that ensure the negative feedback interconnection of two hybrid conic systems is stable.
The input-output properties of gain-scheduled systems are also investigated. We show that a gain-scheduled system composed of conic subsystems has conic bounds as well. Using the conic bounds of the subsystems along with the scheduling signal properties, the overall conic bounds of the gain-scheduled system can be calculated. We also show that when hybrid very strictly passive/finite gain (VSP/finite gain) subsystems are gain-scheduled, the overall map is also hybrid VSP/finite gain.
Being concerned with the control of aerospace systems, we use the theory developed in this thesis to control two interesting plants. We consider passivity-based control of a spacecraft endowed with magnetic torque rods and reaction wheels. In particular, we synthesize a LTV input strictly passive controller. Using hybrid theory we control single- and two-link flexible manipulators. We present two controller synthesis schemes, each of which employs numerical optimization techniques and attempts to have the hybrid VSP/finite gain controllers mimic a H2 controller. One of our synthesis methods uses the Generalized Kalman-Yakubovich-Popov Lemma, thus realizing a convex optimization problem.
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Forbes, James Richard. "Design of Optimal Strictly Positive Real Controllers Using Numerical Optimization for the Control of Large Flexible Space Structures." Thesis, 2008. http://hdl.handle.net/1807/11142.
Full textAbstract:
The design of optimal strictly positive real (SPR) compensators using numerical optimization
is considered. The plants to be controlled are linear and nonlinear flexible manipulators.
For the design of SISO and MIMO linear SPR controllers, the optimization
objective function is defined by reformulating the H2-optimal control problem subject
to the constraint that the controllers must be SPR. Various controller parameterizations
using transfer functions/matrices and state-space equations are considered. Depending
on the controller form, constraints are enforced (i) using simple inequalities guaranteeing
SPRness, (ii) in the frequency domain, or (iii) by implementing the Kalman-Yakubovich-
Popov lemma. The design of a gain-scheduled SPR controller using numerical optimization
is also considered. Using a family of linear SPR controllers, the time dependent
scheduling signals are parameterized, and the objective function of the optimizer seeks
to find the form of the scheduling signals which minimizes the manipulator tip tracking
error while minimizing the control effort.
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Piccinelli, Nicola. "Constrained Optimal Control for Semi-Autonomous Robotic Systems." Doctoral thesis, 2022. https://hdl.handle.net/11562/1079867.
Full textAbstract:
An autonomous robotic system can make decisions and perform actions without direct control, handling real-world conditions that are unpredictable and dynamic. In recent years, the research interest in robotic-assisted minimally invasive surgery is shifting from teleoperated devices to autonomous support systems for the execution of repetitive surgical steps (i.e., suturing, ablation and microscopic image scanning). This thesis aims to investigate the design of a supervisory controller for a semi-autonomous robotic system and the application of optimal control techniques to manage unexpected events and constraints during the execution of surgery. The management of such events will be demanded by the surgeon through a novel formulation of constrained bilateral teleoperation. For this reason, particular focus will be given to addressing MPC problems under input-output and state constraints for linear, non-linear and hybrid (i.e., with both continuous and discrete dynamics) systems. These constraints will be used to guarantee stability and enforce safety conditions during the teleoperated intervention. The thesis will also cover the research activities necessary to develop the EU funded H2020 SARAS semi-autonomous system. Such activities include the definition of a shared reference system for the multi-arm robotic setup and the registration of 3D preoperative medical data to the patient's anatomy.
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King, Brian M. (Brian Matthew). "Natural circulation scaling of a pressurized conduction cooldown event in the upper plenum of the modular high temperature gas reactor." Thesis, 2012. http://hdl.handle.net/1957/30342.
Full textAbstract:
In a Modular High Temperature Gas Reactor (MHGTR), the Pressurized Conduction Cooldown (PCC) event is an accident scenario in which there is a loss of forced convection of the coolant through the system but the pressure boundary remains intact. When the PCC event occurs, natural circulation onsets which results in a flow and temperature reversal, resulting in hot helium flowing into the upper plenum which could imping upon the upper plenum head. The High Temperature Test Facility (HTTF), which is being designed and constructed at Oregon State University, is a scaled thermal test facility of the MHTGR which is being built for both code validation purposes and to examine specific flow phenomena of the gas reactor. This study is being performed to determine how the HTTF simulates the same conditions as the MHTGR under this scenario through the use of scaling parameters and computational fluid dynamics.Graduation date: 2013
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Μπράτης, Ιωάννης-Διονύσιος. "Συμβατικός και ευφυής έλεγχος σε φωτοβολταϊκή εγκατάσταση." Thesis, 2014. http://hdl.handle.net/10889/8239.
Full textAbstract:
Στην παρούσα διπλωματική εργασία προσομοιώθηκε, μέσω του προγράμματος Matlab
και συγκεκριμένα μέσω της εργαλειοθήκης Simulink, ένα υβριδικό μικροδίκτυο το οποίο
αποτελούνταν από μια φωτοβολταϊκή διάταξη των 85W, ένα συσσωρευτή ιόντων-λιθίου (Liion
battery), δυο DC-DC μετατροπείς και ένα R-L φορτίο. Στην συνέχεια πραγματοποιήθηκαν
4 διαφορετικές τεχνικές ελέγχου σε 2 σημεία, έναν στην πλευρά του φωτοβολταϊκού και έναν
στην πλευρά της μπαταρίας. Ο έλεγχος στην πλευρά του φωτοβολταϊκού στόχευε το ρεύμα
του φωτοβολταϊκού κάθε χρονική στιγμή να έχει την κατάλληλη τιμή προκειμένου να
επιτυγχάνεται η μέγιστη ισχύς μέσω σημείου απόδοσης της μέγιστης ισχύος (MPPT). Ο
έλεγχος στην πλευρά της μπαταρίας έχει ως σκοπό την διατήρηση της τάσης του φορτίου στα
100 V.(Vload_reference=100V). Οι έλεγχοι που πραγματοποιήθηκαν ήταν με χρήση PI ελεγκτών,
έλεγχοι εκμεταλλευόμενοι την παθητικότητα του Euler-Lagrange συστήματος (PBC), με
χρήση ασαφών (fuzzy) ελεγκτών και με χρήση νευρο-ασαφών (neuro-fuzzy) ελεγκτών.In this diploma thesis a DC hybrid microgrid was simulated by using the program Matlab and specifically the toolbox Simulink. The microgrid consists of a photovoltaic array, a Li-ion battery storage, two DC-DC converters and an R-L load. Four different control methods were then applied to our system in 2 places, one on the photovoltaic array and one on the battery. The one on the photovoltaic array aimed that the PV current would be such that every time the maximum power from the PV would be achieved through a maximum power point tracker. The one on the battery has the purpose of maintaining the load voltage at 100 Volts. The control methods which were implied were PI controllers, passivity based control, fuzzy controllers and neuro-fuzzy controllers.
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Gurrala, Gurunath. "Power System Stabilizing Controllers - Multi-Machine Systems." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1986.
Full textAbstract:
Electrical Power System is one of the most complex real time operating systems. It is probably one of the best examples of a large interconnected nonlinear system of varying nature. The system needs to be operated and controlled with component or system problems, often with combinatorial complexity. In addition, time scales of operation and control can vary from milliseconds to minutes to hours. It is difficult to maintain such a system at constant operating condition due to both small and large disturbances such as sudden change in loads, change in network configuration, fluctuations in turbine output, and various types of faults etc. The system is therefore affected by a variety of instability problems. Among all these instability problems one of the important modes of instability is related to dynamic instability or more precisely the small perturbation oscillatory instability. Oscillations of small magnitude and low frequency (in the range of 0.1Hz to 2.5Hz) could persist for long periods, limiting the power transfer capability of the transmission lines. Power System Stabilizers (PSS) were developed as auxiliary controllers on the excitation system to improve the system damping performance by modulating the generator excitation voltage. However, the synthesis of an effective PSS for all operating conditions still remains a difficult and challenging task.
The design and tuning of PSS for robust operation is a laborious process. The existing PSS design techniques require considerable expertise, the complete system information and extensive eigenvalue calculations which increases the computational burden as the system size increases. Conventional automatic voltage regulator (AVR) and PSS designs are based on linearized models of power systems which fail to stabilize the system over a wide range of operating conditions. In the last decade or so, a variety of nonlinear control techniques have become available. In this thesis, an attempt is made to explore the suitability of some of these design techniques for designing excitation controllers to enhance small perturbation stability of power systems over a wide range of operating and system conditions.
This thesis first proposes a method of designing power system stabilizers based on local measurements alone, in multi-machine systems. Next, a method has been developed to analyze and quantify the small signal performance benefits of replacing the existing AVR+PSS structure with nonlinear voltage regulators. A number of new nonlinear controller designs have been proposed subsequently. These include, (a) a new decentralized nonlinear voltage regulator for multi machine power systems with a single tunable parameter that can achieve effective trade of between both the voltage regulation and small signal objectives, (b) a decentralized Interconnection and Damping Assignment Passivity Based Controller in addition to a proportional controller that can achieve all the requirements of an excitation system and (c) a Nonlinear Quadratic Regulator PSS using Single Network Adaptive Critic architecture in the frame work of approximate dynamic programming. Performance of all the proposed controllers has been analyzed using a number of multi machine test systems over a range of operating conditions.