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Surveillance préventive des systèmes hybrides à incertitudes bornées / Preventive monitoring of hybrid systems in a bounded-error frameworkMaÏga, Moussa 02 July 2015 (has links)
Cette thèse est dédiée au développement d’algorithmes génériques pour l’observation ensembliste de l’état continu et du mode discret des systèmes dynamiques hybrides dans le but de réaliser la détection de défauts. Cette thèse est organisée en deux grandes parties. Dans la première partie, nous avons proposé une méthode rapide et efficace pour le passage ensembliste des gardes. Elle consiste à procéder à la bissection dans la seule direction du temps et ensuite faire collaborer plusieurs contracteurs simultanément pour réduire le domaine des vecteurs d’état localisés sur la garde, durant la tranche de temps étudiée. Ensuite, nous avons proposé une méthode pour la fusion des trajectoires basée sur l'utilisation des zonotopes. Ces méthodes, utilisées conjointement, nous ont permis de caractériser de manière garantie l'ensemble des trajectoires d'état hybride engendrées par un système dynamique hybride incertain sur un horizon de temps fini. La deuxième partie de la thèse aborde les méthodes ensemblistes pour l'estimation de paramètres et pour l'estimation d'état hybride (mode et état continu) dans un contexte à erreurs bornées. Nous avons commencé en premier lieu par décrire les méthodes de détection de défauts dans les systèmes hybrides en utilisant une approche paramétrique et une approche observateur hybride. Ensuite, nous avons décrit deux méthodes permettant d’effectuer les tâches de détection de défauts. Nous avons proposé une méthode basée sur notre méthode d'atteignabilité hybride non linéaire et un algorithme de partitionnement que nous avons nommé SIVIA-H pour calculer de manière garantie l'ensemble des paramètres compatibles avec le modèle hybride, les mesures et avec les bornes d’erreurs. Ensuite, pour l'estimation d'état hybride, nous avons proposé une méthode basée sur un prédicteurcorrecteur construit au dessus de notre méthode d'atteignabilité hybride non linéaire. / This thesis is dedicated to the development of generic algorithms for the set-membership observation of the continuous state and the discrete mode of hybrid dynamical systems in order to achieve fault detection. This thesis is organized into two parts. In the first part, we have proposed a fast and effective method for the set-membership guard crossing. It consists in carrying out bisection in the time direction only and then makes several contractors working simultaneously to reduce the domain of state vectors located on the guard during the study time slot. Then, we proposed a method for merging trajectories based on zonotopic enclosures. These methods, used together, allowed us to characterize in a guaranteed way the set of all hybrid state trajectories generated by an uncertain hybrid dynamical system on a finite time horizon. The second part focuses on set-membership methods for the parameters or the hybrid state (mode and continuous state) of a hybrid dynamical system in a bounded error framework. We started first by describing fault detection methods for hybrid systems using the parametric approach and the hybrid observer approach. Then, we have described two methods for performing fault detection tasks. We have proposed a method for computing in a guaranteed way all the parameters consistent with the hybrid dynamical model, the actual data and the prior error bound, by using our nonlinear hybrid reachability method and an algorithm for partition which we denote SIVIA-H. Then, for hybrid state estimation, we have proposed a method based on a predictor-corrector, which is also built on top of our non-linear method for hybrid reachability.
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Análise de estabilidade de sistemas dinâmicos híbridos e descontínuos modelados por semigrupos /Pena, Ismael da Silva. January 2008 (has links)
Resumo: Sistemas dinâmicos híbridos se diferenciam por exibir simultaneamente variados tipos de comportamento dinâmico (contínuo, discreto, eventos discretos) em diferentes partes do sistema. Neste trabalho foram estudados resultados de estabilidade no sentido de Lyapunov para sistemas dinâmicos híbridos gerais, que utilizam uma noção de tempo generalizado, definido em um espaço métrico totalmente ordenado. Mostrou-se que estes sistemas podem ser imersos em sistemas dinâmicos descontínuos definidos em R+, de forma que sejam preservadas suas propriedades qualitativas. Como foco principal, estudou-se resultados de estabilidade para sistemas dinâmicos descontínuos modelados por semigrupos de operadores, em que os estados do sistema pertencem à espaços de Banach. Neste caso, de forma alternativa à teoria clássica de estabilidade, os resultados não utilizam as usuais funções de Lyapunov, sendo portanto mais fáceis de se aplicar, tendo em vista a dificuldade em se encontrar tais funções para muitos sistemas. Além disso, os resultados foram aplicados à uma classe de equações diferenciais com retardo. / Abstract: Hybrid dynamical systems are characterized for showing simultaneously a variety of dynamic behaviors (continuous, discrete, discrete events) in different parts of the System. This work discusses stability results in the Lyapunov sense for general hybrid dynamical systems that use a generalized notion of time, defined in a completely ordered metric space. It has been shown that these systems may be immersed in discontinuous dynamical systems defined in R+, so that their quality properties are preserved. As the main focus, it is studied stability results for discontinuous dynamical systems modeled by semigroup operators, in which the states belong to Banach spaces. In this case, an alternative to the classical theory of stability, the results do not make use of the usual Lyapunov functions, and therefore are easier to apply, in view of the difficulty in finding such functions for many systems. Furthermore, the results were applied to a class of time-delay discontinuous differential equations. / Orientador: Geraldo Nunes Silva / Coorientador: Luís Antônio Fernandes de Oliveira / Banca: Carlos Alberto Raposo da Cunha / Banca: Waldemar Donizete Bastos / Mestre
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Reglerentwurf zur dezentralen Online-Steuerung von Lichtsignalanlagen in StraßennetzwerkenLämmer, Stefan 18 September 2007 (has links)
Die Dissertationsschrift widmet sich einer systemtheoretischen Untersuchung zur verkehrsabhängigen Steuerung von Lichtsignalanlagen in Straßennetzwerken. Aus einem mathematischen Modell für den Verkehrsablauf auf Knotenzufahrten wird ein Verfahren abgeleitet, mit dem sich Umschaltzeitpunkte und Phasenwechsel flexibel an das tatsächliche Verkehrsgeschehen anpassen lassen. Der Ansatzpunkt ist, die einzelnen Knotenpunkte des Netzwerks lokal zu optimieren. Eine "Grüne Welle" soll sich von selbst einstellen, und zwar genau dann, wenn dadurch lokal Wartezeiten eingespart werden. Indem die lokale Optimierung in ein lokales Stabilisierungsverfahren eingebettet wird, können Instabilitäten aufgrund netzwerkweiter Rückkopplungen ausgeschlossen werden. Das vorgestellte Verfahren setzt sich aus drei Teilen zusammen: (i) einem lokalen Prognoseverfahren zur Bewertung von Schaltzuständen und Phasenübergängen bezüglich zukünftig entstehender Wartezeiten, (ii) einem lokalen Optimierungsverfahren, das jeder Phase einen dynamischen Prioritätsindex zuweist und die Phase mit höchster Priorität zur Bedienung auswählt und (iii) einem lokalen Stabilisierungsverfahren, das zum Einhalten einer mittleren und einer maximalen Bedienperiode korrigierend in die lokale Optimierung eingreift. Indem die Knotenpunkte ausschließlich über die Verkehrsströme gekoppelt sind, ergeben sich die Umschaltzeitpunkte unmittelbar aus den Ankunftszeitpunkten der Fahrzeuge selbst. Die Phasenwechsel stellen sich somit von selbst bedarfsgerecht ein. Simulationsergebnisse machen deutlich, dass sich aufgrund der höheren Flexibilität sowohl die Wartezeiten als auch der Kraftstoffverbrauch senken lassen.
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Modelling and Investigation of Control of a Power Infrastructure Resource Management System for a Radio Base Station : A study on sustainable power management for ICT infrastructure. / Modellering och Undersökning av Styrmetoder av Resurshanterning för en Radio Basstation : En studie angående hållbar effekthantering för ICT infrastruktur.Lenart, Gustav January 2023 (has links)
In order to minimize greenhouse gas emissions and operational cost related to the ICT-infrastructure the power management method of a Radio Base Station (RBS) or Base Transceiver Station (BTS) at Ericsson is studied and modelled. The major load demand at RBS’s are due to uplink and downlink data traffic. Ericssons RBS’s contains power resources and energy storage systems that are controlled by a power controller module in order to meet load demand. Such power resources may be AC-grid, generator and photovoltaic cells etc. Using a certain power resource entails a distinct cost and emission. This thesis investigates the influence that the power controller logic has on cost and emission using two frameworks. One framework models the power resource management in the form of a hybrid dynamical system. Using this framework a new management policy is investigated and compared with the current management policy. The second framework investigates the usage of MPC for controlling the power sources during operation. Using this framework a third management policy is introduced and compared with the current implementation. The performance of the three management policies are compared by simulating a standard RBS operation scenario. The results show that during a RBS scenario where the grid will never fail the third management method using MPC outperforms the other two management policies. In the RBS scenario that the grid may fail the second management method outperforms the current implementation. The implication of these results may be that during a scenario of no grid failure it is more advantageous to decrease emission and cost by using a supervisory control method. During a scenario where grid failure may occur using the second management method, where battery is used as more than just a back-up unit, is more advantageous for decreasing emission and cost. / För att minimera utsläpp av växthusgaser och driftskostnader inom ICT-infrastrukturen studeras och modelleras effekt-hanteringen för en radiobasstation (RBS) eller Base Transceiver Stations (BTS) på Ericsson. Det stora belastningsbehovet hos en RBS beror på upplänk och nedlänksdatatrafik. Ericssons RBS innehåller kraftresurser och energi lagringssystem som styrs av en effektkontrollmodul för att möta lastbehovet. Sådana kraftresurser kan vara AC-nät, generator eller solceller etc. Användandet av en viss kraftresurs medför en distinkt driftkostnad och utsläpp. Detta examensarbete undersöker effekten som kontrollmodulens logik har på kostnad och emission genom två tillvägagångssätt. Ett tillvägagångssätt modellerar effekt-hanteringen i form av ett hybrid dynamiskt system. Med detta tillvägagångssätt utreds en ny resurs förvaltningspolicy och jämförs med den nuvarande implementerade policyn. Det andra tillvägagångssättet undersöker användningen av MPC för att styra effekt-hanteringen under drift. Detta tillvägagångssätt leder till en tredje förvaltningspolicy som jämförs med den nuvarande implementerade policyn. Prestandan av de tre förvaltningspolicyerna jämförs genom att simulera olika scenarion av RBS-drift. Resultaten visar att under ett RBS-scenario där nätet aldrig kommer att förloras överträffar den tredje förvaltningspolicyn som använder MPC, de andra två förvaltningsmetoderna. I ett RBS scenario där nätet kan förloras överträffar den andra förvaltningsmetoden den nuvarande implementeringen. Resultaten tyder på att under ett scenario utan nätfel är det mer fördelaktigt för att minska utsläpp och kostnader genom att använda den tredje förvaltningsmetoden. Under ett scenario där nätfel kan inträffa är den andra förvaltningsmetoden, där batteriet används som mer än bara en reservenhet, mer fördelaktig för att minska utsläpp och kostnader.
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Nonlinear Impulsive and Hybrid Dynamical SystemsNersesov, Sergey G 23 June 2005 (has links)
Modern complex dynamical systems typically possess a
multiechelon hierarchical hybrid structure characterized by
continuous-time dynamics at the lower-level units and logical
decision-making units at the higher-level of hierarchy. Hybrid
dynamical systems involve an interacting countable collection of
dynamical systems defined on subregions of the partitioned state
space. Thus, in addition to traditional control systems, hybrid
control systems involve supervising controllers which serve to
coordinate the (sometimes competing) actions of the lower-level
controllers. A subclass of hybrid dynamical systems are impulsive
dynamical systems which consist of three elements, namely, a
continuous-time differential equation, a difference equation, and
a criterion for determining when the states of the system are to
be reset. One of the main topics of this dissertation is the
development of stability analysis and control design for impulsive
dynamical systems. Specifically, we generalize Poincare's
theorem to dynamical systems possessing left-continuous flows to
address the stability of limit cycles and periodic orbits of
left-continuous, hybrid, and impulsive dynamical systems. For
nonlinear impulsive dynamical systems, we present partial
stability results, that is, stability with respect to part of the
system's state. Furthermore, we develop adaptive control framework
for general class of impulsive systems as well as energy-based
control framework for hybrid port-controlled Hamiltonian systems.
Extensions of stability theory for impulsive dynamical systems
with respect to the nonnegative orthant of the state space are
also addressed in this dissertation. Furthermore, we design
optimal output feedback controllers for set-point regulation of
linear nonnegative dynamical systems. Another main topic that has
been addressed in this research is the stability analysis of
large-scale dynamical systems. Specifically, we extend the theory
of vector Lyapunov functions by constructing a generalized
comparison system whose vector field can be a function of the
comparison system states as well as the nonlinear dynamical system
states. Furthermore, we present a generalized convergence result
which, in the case of a scalar comparison system, specializes to
the classical Krasovskii-LaSalle invariant set theorem. Moreover,
we develop vector dissipativity theory for large-scale dynamical
systems based on vector storage functions and vector supply rates.
Finally, using a large-scale dynamical systems perspective, we
develop a system-theoretic foundation for thermodynamics.
Specifically, using compartmental dynamical system energy flow
models, we place the universal energy conservation, energy
equipartition, temperature equipartition, and entropy
nonconservation laws of thermodynamics on a system-theoretic
basis.
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Contribution à la commande de systèmes non linéaires sous échantillonnage apériodique / Contribution to the control of nonlinear systems under aperiodic samplingOmran, Hassan 24 March 2014 (has links)
Cette thèse est dédiée à l’analyse de stabilité des systèmes non linéaires sous échantillonnage variant avec le temps. Lors de l’implémentation numérique d’un contrôleur qui est calculé en temps-continu (approche par émulation), il est d'un grand intérêt de fournir des critères de stabilité et d’estimer la borne supérieure de l’intervalle d’échantillonnage qui garantit la stabilité du système en temps discret. Plusieurs travaux récents ont abordé ces questions dans le cas de modèles linéaires, mais la question a rarement été abordée dans une étude quantitative et formelle pour les systèmes non linéaires.Tout d'abord, le mémoire présente un aperçu sur les systèmes échantillonnés. Les défis et les principales méthodes pour l'analyse de stabilité sont présentés pour le cas des systèmes linéaires invariants dans le temps et celui des systèmes non linéaires. Ensuite, l’analyse de la stabilité locale des systèmes bilinéaires échantillonnés contrôlés par un retour d'état linéaire est considérée. Deux approches sont utilisées, la première basée sur la théorie des systèmes hybrides, la seconde basée sur l’analyse des ensembles invariants contractants. Cette dernière approche est inspirée par la théorie de la dissipativité. L’ensemble de ces résultats conduisent à des conditions suffisantes de stabilité exprimées sous forme LMI.Enfin, les conditions de stabilité basées sur la dissipativité sont étendues au cas des systèmes non linéaires affines en l'entrée. Les résultats sont ensuite repris dans le cas spécifique des systèmes non linéaires polynomiaux où les conditions de stabilité sont vérifiées numériquement en utilisant la décomposition en somme des carrés (SOS). / This PhD thesis is dedicated to the stability analyzis of nonlinear systems under sampled-data control, with arbitrarily time-varying sampling intervals. When a controller is designed in continuous-time, and then implemented digitally (emulation approach), it is of great interest to provide stability criteria, and to estimate the bound on the sampling intervals which guarantees the stability of the sampled-data system. Whereas several works deal with linear models, the issue has been rarely addressed in a formal quantitative study in the nonlinear case.First, an overview on sampled-data control is presented. Challenges and main methodologies for stability analysis are presented for both the linear time-invariant and the nonlinear cases.Then, local stability of bilinear sampled-data systems controlled by a linear state feedback is considered by using two approaches: the first one is based on hybrid systems theory; the second one is based on the analyzis of contractive invariant sets and is inspired by the dissipativity theory. Both approaches provide sufficient stability conditions in the form of LMI.Finally, the dissipativity–based stability conditions are extended for the more general case of nonlinear systems which are affine in the input, including the case of polynomial systems which leads to conditions in the form of sum of squares (SOS).
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