Tesis sobre el tema "Réduction active de vibration"
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Farah, Philippe-Siad. "Étude de la réduction des vibrations des machines synchrones". Grenoble INPG, 1995. http://www.theses.fr/1995INPG0087.
Texto completoCassoret, Bertrand. "Réduction active du bruit magnétique des machines asynchrones directement connectées au réseau". Phd thesis, Université d'Artois, 1996. http://tel.archives-ouvertes.fr/tel-00372876.
Texto completoLe premier chapitre expose le phénomène, fait une synthèse des relations mécaniques et acoustiques existantes et les confronte avec des expériences pratiques.
Une méthode de calcul des harmoniques d'induction présents dans l'entrefer est développée dans le deuxième chapitre, ils sont responsables des forces de Maxwell à l'origine du bruit. Les relations obtenues sont valables pour un moteur à rotor bobiné ou à cage et permettent la détermination des harmoniques de courant rotorique et statorique. Elles sont comparées à celles données par d'autres auteurs qui négligent certains termes.
Les applications numériques présentées dans le troisième chapitre soulignent l'importance d'un phénomène qualifié de résonance de denture, responsable de courants rotoriques harmoniques importants et de bruit magnétique. Elles montrent également la validité de la théorie en comparant les résultats aux relevés pratiques.
Le dernier chapitre expose le principe de réduction active du bruit magnétique. Il consiste à injecter un faible courant harmonique créant une force qui s'oppose à celle à l'origine du bruit. Plusieurs montages sont proposés, permettant l'injection d'un courant supplémentaire dans une machine alimentée par le réseau. L'étude expérimentale permet de valider le procédé.
Romary, Raphaël. "Modélisation de la machine synchrone à concentration de flux : application à la réduction active des vibrations". Lille 1, 1995. http://www.theses.fr/1995LIL10031.
Texto completoGeoffriault, Maud. "Réduction active des vibrations et des bruits d'une machine électrique par la stratégie de commande". Thesis, CentraleSupélec, 2015. http://www.theses.fr/2015SUPL0003/document.
Texto completoThis work takes place in the context of the development of powertrains for electric vehicles. Those developments have raised new issues such as noise and vibrations of electrical machines, which are important issues in automotive applications. The aim of this thesis is to develop control laws dedicated to the reduction of currents harmonics that are responsible for vibration harmonics.In that purpose, different parts of the system have been modelled. Parameters of the electrical model of the studied machine have then been identified thanks to experimental measurements.Two different control laws are proposed and developed. One the one hand, a controller is synthetized thanks to H-infinity optimization. On the other hand, the studied current harmonic is modelled as coming from an external disturbance. This virtual disturbance is estimated thanks to an observer and compensated
Wang, Peng. "Active vibration control in a specific zone of smart structures". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEC007/document.
Texto completoThis research aims at solving a particular vibration control problem of smart structures. We aim at reducing the vibration in a specific zone of the smart structure under the disturbance that covers a wide frequency band. Moreover, at this specific zone, neither actuation nor sensing is possible.Here we face several main challenges. First, we need to control the vibration of a specific zone of the structure while we only have access to measurements at other zones. Second, the wide bandwidth of the disturbance implies that numerous modes should be controlled at the same time which requires the use of multiple actuators and sensors. This leads to a MIMO controller which is difficult to obtain using classical controller design methods. Third, the so-called spillover problem must be avoided which is to guarantee the closed-loop stability when the model-based controller is applied on the actual setup. To tackle these challenges, we investigate two control strategies: the centralized control and the distributed control.For centralized control, we propose a methodology that allows us to obtain a simple MIMO controller that accomplishes these challenges. First, several modeling and identification techniques are applied to obtain an accurate low-order model of the smart structure. Then, an H_∞ control based synthesis method with a particularly proposed H_∞ criterion is applied. This H_∞ criterion integrates multiple control objectives, including the main challenges. In particular, the spillover problem is transformed into a robust stability problem and will be guaranteed using this criterion. The obtained H_∞ controller is a standard solution of the H_∞ problem. The final controller is obtained by further simplifying this H_∞ controller without losing the closed-loop stability and degrading the performance. This methodology is validated on a beam structure with piezoelectric transducers and the central zone is where the vibration should be reduced. The effectiveness of the obtained controller is validated by simulations and experiments.For distributed control, we consider the same beam structure and the same control objectives. There exist methods aiming at designing distributed controllers of spatially interconnected system. This research proposes a FEM based method, combined with several model reduction techniques, that allows to spatially discretize the beam structure and deduce the state-space models of interconnected subsystems. The design of distributed controllers will not be tackled in this research
Lecointe, Jean-Philippe. "Etude et réduction active du bruit d'origine magnétique des machines à réluctance variable à double saillance". Artois, 2003. http://www.theses.fr/2003ARTO0203.
Texto completoAn analytical model of doubly salient switched reluctance machine magnetic noise prediction and a new technique of active noise reduction are proposed. The studied machine is described as well as the analytical expressions permitting the determination of mechanical deformations and acoustic intensity. The main contribution of this research consists in determining analytical expressions of magnetic origin forces which create vibrations and noise. A 2kW 8/6 machine permits to validate several theoretical points such as mechanical resonance frequencies, phase inductances or vibratory and acoustical spectra. Existent noise reduction process are also described as well as influences of geometric parameters - such as teeth or yoke dimensions- on noise. At last, a new technique using current injection into auxiliary windings is performed and validated on an available prototype
Brakna, Mohammed. "Sensor and actuator optimal location for dynamic controller design. Application to active vibration reduction in a galvanizing process". Electronic Thesis or Diss., Université de Lorraine, 2023. https://docnum.univ-lorraine.fr/ulprive/DDOC_T_2023_0152_BRAKNA.pdf.
Texto completoThe aims of the present PhD thesis are to determine a model that is both sufficiently accurate and numerically exploitable to propose optimal placement of sensors and actuators for active vibration control in a galvanizing line. A continuous hot-dip galvanizing process consists in covering a metal (here: a steel band) by a protective layer of zinc which avoids the corrosion due to the air. The thickness of this layer must be constant to guarantee the mechanical properties and surface condition of the product. In a galvanizing line, the moving steel strip is heated and then immersed in a liquid zinc bath before being wiped out by nozzles projecting air. The air flow, as well as the rotation of the driving rolls, among other things, creates vibrations affecting the wiping process and thus the regularity of the zinc deposit. Active control is therefore necessary, for example by means of electromagnets placed on either side of the moving steel strip. In a first step, a behavioral model of the steel strip taking into account the presence and propagation of vibrations was obtained by spatial discretization of a partial differential equation. This state space model was validated in simulation and experimentally on a pilot galvanizing line of ArcelorMittal Research in Maizières-lès-Metz. Once this model is established, the objective of the study is to find the optimal placement of sensors, to measure the vibrations of the strip as efficiently as possible, but also of actuators to minimize the amplitude of these vibrations by an appropriate control law. These problems of optimal placement are at the heart of the issues of active vibration control and are found in many fields of application. An optimal placement method based on Gramian maximization has been proposed in order to reduce the impact of disturbances on the system. Different control strategies have been considered such as (i) observed state feedback based on Kalman filter and LQ regulator; and (ii) extended observed state feedback to improve the results by also taking into account the disturbance estimation provided by a PI (proportional-integral) observer. Simulation and experimental results illustrate the thesis contributions
Karim, Yassine. "Caractérisation robuste de liaisons amortissantes avec dispositifs piezo-électriques pour la réduction de vibrations de structures". Phd thesis, Conservatoire national des arts et metiers - CNAM, 2013. http://tel.archives-ouvertes.fr/tel-00953330.
Texto completoLauzier, Kevin. "Analyse et réduction des vibrations d'un refroidisseur cryogénique pour application spatiale : de la modélisation multiphysique à la commande non linéaire". Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI071.
Texto completoEarth observation satellites for meteorological, scientific or military applications sometimes carry infrared imagers. These cameras need to be cooled down to very low temperatures in order to avoid blurry infrared pictures of the Earth, due to the thermal noise of the detector or heat sources nearby. This PhD thesis focuses on a pulse tube cryocooler used in such applications. It deals with induced vibrations as they can destabilize the satellite or make the camera focal plane move. The goals are to understand and reduce the vibrations induced by the pulse tube cryocooler. These PhD works are composed of two main parts. First, the cryocooler is analyzed and modelled to reproduce observed induced vibrations. This global multiphysics model is aimed at identifying dissymmetry, non-linearity and mechanical behaviors which cause vibrations. This approach uses different fields of science such as electromagnetism, mechanics, fluid mechanics and thermodynamics. Sensitivity studies are done and the model is confronted to experiments highlighting measurement tools limits and checking methodologies. Next, vibration reduction using control strategies is studied. The whole control loop is questioned. The improvements proposed concern the vibration sensors, the frequency analysis algorithm, the vibration reduction algorithm and the type of control. Solutions for control, conception and manufacturing resulting from this PhD work offer opportunities to improve the system and lower its cost
Kidner, Michael Roger Francis. "An active vibration neutraliser". Thesis, University of Southampton, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299609.
Texto completoMcKinnell, Robert James. "Active isolation of vibration". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306465.
Texto completoCambou, Pierre E. "A Distributed Active Vibration Absorber (DAVA) for Active-Passive Vibration and Sound Radiation Control". Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/10105.
Texto completoMaster of Science
Ulker, Fatma Demet. "Active Vibration Control Of Smart Structures". Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/4/1098409/index.pdf.
Texto completocontrol strategies in order to suppress the free and forced vibrations of smart structures. The smart structures analyzed in this study were the smart beam and the smart ¯
n. They were aluminum passive structures with surface bonded PZT (Lead-Zirconate-Titanate) patches. The structures were considered in clamped-free con¯
guration. The ¯
rst part of this study focused on the identi¯
cation of nominal system models of the smart structures from the experimental data. For the experimentally identi¯
ed models the robust controllers were designed by using H1 and ¹
-synthesis strategies. In the second part, the controller implementation was carried out for the suppression of free and forced vibrations of the smart structures. Within the framework of this study, a Smart Structures Laboratory was established in the Aerospace Engineering Department of METU. The controller implementations were carried out by considering two di®
erent experimental set-ups. In the ¯
rst set-up the controller designs were based on the strain measurements. In the second approach, the displacement measurements, which were acquired through laser displacement sensor, were considered in the controller design. The ¯
rst two °
exural modes of the smart beam were successfully controlled by using H1 method. The vibrations of the ¯
rst two °
exural and ¯
rst torsional modes of the smart ¯
n were suppressed through the ¹
-synthesis. Satisfactory attenuation levels were achieved for both strain measurement and displacement measurement applications.
Ganguli, ABHIJIT. "Chatter reduction through active vibration damping". Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210980.
Texto completoThe regenerative process theory explains chatter as a closed loop interaction between the structural dynamics and the cutting process. This is considered to be the most dominant reason behind machine tool chatter although other instability causing mechanisms exist.
The stability lobe diagram provides a quantitative idea of the limits of stable machining in terms of two physical parameters: the width of contact between tool and the workpiece, called the width of cut and the speed of rotation of the spindle. It is found that the minimum value of the stability limit is proportional to the structural damping ratio for turning operations. This important finding provides the motivation of influencing the structural dynamics by active damping to enhance stability limits of a machining operation.
A direct implementation of active damping in an industrial environment may be difficult. So an intermediate step of testing the strategy in a laboratory setup, without conducting real cutting is proposed. Two mechatronic "Hardware in the Loop" simulators for chatter in turning and milling are presented, which simulate regenerative chatter experimentally without conducting real cutting tests. A simple cantilever beam, representing the MDOF dynamics of
the machine tool structure constitutes the basic hardware part and the cutting process is simulated in real time on a DSP board. The values of the cutting parameters such as spindle speed and the axial width of cut can be changed on the DSP board and the closed loop interaction between the structure and the cutting process can be led to instability.
The demonstrators are then used as test beds to investigate the efficiency of active damping, as a potential chatter stabilization strategy. Active damping is easy to implement, robust and does not require a very detailed model of the structure for proper functioning, provided a collocated sensor and actuator configuration is followed. The idea of active damping is currently being implemented in the industry in various metal cutting machines as part of the European Union funded SMARTOOL project (www.smartool.org), intended to propose smart chatter control technologies in machining operations.
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Chang, Min-Yung. "Active vibration control of composite structures". Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115021/.
Texto completoLi, Xiao Dong. "Active vibration control of vehicle suspension". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=67007.
Texto completoLe bruit de vibration structurelle produit par le contact des pneus du véhicule sur la surface de la route est un facteur important du bruit à l'intérieur du véhicule. Ce type de bruit à basse fréquence peut affecter sérieusement la concentration du conducteur et le confort des passagers. De manière à réduire ce bruit de vibration, un contrôle actif de vibration dans la suspension du véhicule est proposé, en contraste avec la réduction active de bruit acoustique. Puisqu'il est inévitable d'avoir des incertitudes dans le modèle de la dynamique de transmission de la vibration, des contrôleurs rétroactifs robustes sont considérés. Dans cette thèse, un contrôleur robuste H-infini et un contrôleur à synthèse mu sont conçus pour réduire la vibration en utilisant des actionneurs agissant directement sur la suspension. En premier lieu, des résultats de simulation obtenus sur une suspension d'une seule roue à l'Université de Sherbrooke démontrent une réduction significative de la vibration. Puis, une simulation des contrôleurs est effectuée sur le modèle de la voiture. Les résultats des tests en boucle fermée sont présentés et l'efficacité des contrôleurs rétroactifs robustes est discutée.
Houlston, Paul Robert. "Active vibration control of rotating machines". Thesis, University of Nottingham, 2007. http://eprints.nottingham.ac.uk/10275/.
Texto completoAbdul, Muthalif Asan Gani. "Active control of high-frequency vibration". Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612225.
Texto completoLau, M. W. S. "Active vibration control at machinery feet". Thesis, Aston University, 2000. http://publications.aston.ac.uk/15340/.
Texto completoHeilmann, John. "A dual reaction-mass dynamic vibration absorber for active vibration control". Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-09182008-063315/.
Texto completoSénéchal, Aurélien. "Réduction de vibrations de structure complexe par shunts piézoélectriques : application aux turbomachines". Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-00862517.
Texto completoCollette, Christophe. "Usure ondulatoire en transport ferroviaire: mécanismes et réduction". Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210701.
Texto completoLes trois premiers chapitres de cette thèse sont dédiés à la description des différents types d'usure ondulatoire et à la présentation des méthodes de prédiction. La méthode de dimensionnement des absorbeurs dynamiques est présentée au chapitre 4, ainsi que quelques perspectives de leur efficacité à réduire l'usure ondulatoire. Dans le chapitre 5, un tronçon réel du RER parisien a été étudié. D'une part les prédictions obtenues par différentes méthodes ont été comparées aux mesures sur site. D'autre part, le bénéfice résultant de l'utilisation d'un absorbeur dynamique a été étudié numériquement. Dans le chapitre 6, le cas de l'usure ondulatoire liée aux vibrations de torsion a été étudié spécifiquement. Un absorbeur dynamique a été développé pour réduire ce type d'usure ondulatoire. Son efficacité a été évaluée théoriquement et numériquement, avec un modèle multi-corps flexible du véhicule et de la voie. Dans le chapitre 7, un absorbeur dynamique visant à réduire les vibrations de torsion d'un essieu de métro à échelle réduite a été construit au laboratoire. Son efficacité a été validée expérimentalement en reproduisant les conditions d'apparition des vibrations de torsion de l'essieu sur le banc d'essais du Laboratoire des Technologies Nouvelles de l'INRETS. La correspondance entre les prédictions d'usure à échelle réduite et à échelle réelle a été établie. Une demande de brevet a été déposée par le Laboratoire des Structures Actives pour ce système (N° 06120344.4).
Doctorat en sciences appliquées
info:eu-repo/semantics/nonPublished
Rentzos, Panagiotis. "Active vibration control of civil engineering structures". Thesis, City University London, 2007. http://openaccess.city.ac.uk/8571/.
Texto completoAnderson, David. "Active control of turbulence-induced helicopter vibration". Thesis, University of Glasgow, 1999. http://theses.gla.ac.uk/2175/.
Texto completoNewman, M. J. "Active vibration control using a distributed controller". Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262146.
Texto completoHyde, T. Tupper. "Active vibration isolation for precision space structures". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11189.
Texto completoBlackwood, Gary H. (Gary Howard). "Active vibration isolation for controlled flexible structures". Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12204.
Texto completoNourzad, Delphine. "Active vibration control of doubly-curved panels". Thesis, University of Southampton, 2014. https://eprints.soton.ac.uk/363620/.
Texto completoStetler, Aaron M. "Active vibration control for free electron lasers". Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FStetler.pdf.
Texto completoThesis advisor(s): Bruce C. Denardo, Thomas J. Hofler. Includes bibliographical references (p. 81). Also available online.
Young, Andrew J. "Active control of vibration in stiffened structures". Title page, contents and abstract only, 1995. http://hdl.handle.net/2440/37722.
Texto completoThesis (Ph.D.)--Mechanical Engineering, 1995.
Berthelot-Richer, Renaud. "Réduction des vibrations d’un capteur électromagnétique héliporté". Mémoire, Université de Sherbrooke, 2013. http://hdl.handle.net/11143/7725.
Texto completoBoultifat, Chaouki Nacer. "Contrôle acoustique actif du bruit dans une cavité fermée". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0134/document.
Texto completoThis thesis deals with active noise control (ANC) in a cavity. The aim is to mitigate the effect of a disturbing sound wave at some points or in a volume. This is achieved using ananti-noise generated, for example, by a loudspeaker. This study requires the use of dynamic models that report changes in pressure at points of interest in response to exogenous noises. Such models can be obtained by frequency identification of point-to-point responses or by using the underlying physical model (wave equation). In the latter case, the search for a low-complexity model (finite dimensional model) is often a prerequisite for the conceptual study of an active control system. The contributions of this thesis concern the development of different simplified models parameterized by the spatial position for acoustic systems, and the design of control laws for noise attenuation. The first part of the thesis is dedicated to the development of various simplified models of acoustic propagation system within a cavity. For that, the simplifications envisaged can be of spatial nature as much as frequential. We show in particular that it is possible, under certain conditions, to approximate the 3D system by a 1D system. This has been demonstrated experimentally on the prototype system, LS2NBox. The second part of the thesis deals with the design of control laws. First, the control strategies commonly used for ANC are compared. The effect of multi-objective H control at different spatial positions close to the attenuation points is analyzed. The possibility of perfect noise cancellation at one point is also discussed
Khan, Irfan Ullah. "Vibration suppression in flexible structures using hybrid active and semi-active control". Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/17682/.
Texto completoBoffa, John. "Model Reduction of Large Structural Systems for Active Vibration Control". University of Technology, Sydney. Faculty of Engineering, 2006. http://hdl.handle.net/2100/338.
Texto completoAkl, Wael Nabil. "Smart foam for active vibration and noise control". College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/222.
Texto completoThesis research directed by: Mechanical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Yousefi-Koma, Aghil. "Active vibration control of smart structures using piezoelements". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq26875.pdf.
Texto completoHoward, Carl. "Active isolation of machinery vibration from flexible structures". Title page, abstract and table of contents only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phh8478.pdf.
Texto completoCopy 2 does not have a CD-ROM. Includes bibliographical references (p. 317-330). Also available in an electronic version.
Wu, Dong-Nan. "Active bounded-state vibration control for structural applications". Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/12326.
Texto completoGeorge, Lynnane E. "Active vibration control of a flexible base manipulator". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/17115.
Texto completoAnanthaganeshan, Kanapathipillai Arunachalam. "Stability and performance of active vibration isolation systems". Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273915.
Texto completoMiller, Scott E. (Scott Edward). "Distributed parameter active vibration control of smart structures". Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/33473.
Texto completoYan, Bo. "Active vibration isolation with a distributed parameter isolator". Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/51281/.
Texto completoMarcotte, Pierre. "A Study of Distributed Active Vibration Absorbers (DAVA)". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/28897.
Texto completoPh. D.
Robu, Bogdan. "Active vibration control of a fluid/plate system". Phd thesis, Toulouse 3, 2010. http://thesesups.ups-tlse.fr/1103/.
Texto completoWe consider the problem of the active reduction of structural vibrations of a plane wing induced by the sloshing of large masses of fuel inside partly full tank. This study focuses on an experimental device composed of an aluminum rectangular plate equipped with piezoelectric actuators/sensors at the clamped end and with a cylindrical tip-tank, more or less filled with liquid, at the opposite free end. The control is performed through piezoelectric actuators and the main difficulty comes from the complex coupling between the flexible modes of the wing and the sloshing modes of the fuel. First, a partial derivative equation model is computed by coupling a plate equation with a Bernoulli equation for the fluid motion. After analyzing the energetic contribution of each mode, a state space approximation is established. After a model matching procedure, a control is computed by using the pole placement method and the H-infinity theory. Due to the large scale of the synthesis model and to the simultaneous performance requirements, a reduced-order H-infinity controller is computed using the HIFOO 2. 0 package and tested on the experimental device for different filling levels. Finally, the problem of simultaneous control with a reduced order HIFOO controller is tackled. Experimental results of this non-convex optimization problem are given and commented
Yousefi-Koma, Aghil Carleton University Dissertation Engineering Mechanical and Aerospace. "Active vibration control of smart structures using piezoelements". Ottawa, 1997.
Buscar texto completoCorton, Rodolphe. "Bruit magnétique des machines asynchrones : procédures de réduction passive et active". Artois, 2000. http://www.theses.fr/2000ARTO0201.
Texto completoThe study presented in this memory concerns the magnetic noise prediction and reduction of asynchronous machines. It is decomposed in seven chapters. The first chapter establish a fast synthesis some results known in the literature. An allusion at the psycho-acoustics is done. It constitutes a first basis on the topic. The second chapter carries on the determination of the flux density in the air-gap of induction machines and therefore the determination of force components to the noise origin. The equations are defined with a fictional pattern of slot in differentiating the coiled rotor and cage. The chapter 3 complete the previous model by some equivalent schemes of the asynchronous machines who takes the slot effect into account. Finally, this approach allows to consider an equivalent motor with smooth iar gap. In the chapter 4, we describe the procedures of noise "passive reduction" who uses for alone elements inductance and capacitor. We remenber the procedures of "active reduction" in this chapter. The chapter 5 proposes a procedure of active reduction based on the utilisation of an auxiliary coil. The done tests show the efficiency of this technique. The chapter 6 concerns the case of the machine powered by a inverter with PWM controls. The harmonic currents delivered by the inverter allows to reduce the noise of the machine. The experimental results let clearly appear that the objective : noise of the machine connected to a inverter < noise of the machine connected to the network is obtained. The chapter 7 proposes a last procedure who makes call to inductance with "virtual air-gap". This one presents the advantage of reducing the nose without interaction between sources
Bolter, J. D. "Active damping of framework vibrations". Thesis, University of Leeds, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382018.
Texto completoHuyanan, Satienpong. "An active vibration absorber for chatter reduction in machining". Thesis, University of Sheffield, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486712.
Texto completoWang, Qishan. "Active vibration and buckling control of piezoelectric smart structures". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114328.
Texto completoL'objectif de cette thése est le contrôle de la vibration et de flambage à l'aide de l'analyse par éléments finis et LQR/LQG technologies de contrôle de rétroaction pour les structures composites stratifiées piézo-électriques qui sont liés ou incorporés de surface de capteurs et d'actionneurs piézoélectriques. Il ya principalement deux parties ciblées. La partie des éléments finis : Deux formulations éléments finis pour les poutres laminées piézo-basé sur le classique d'Euler-Bernoulli et la théorie des poutres de Timoshenko, respectivement, linéaires couplées piézoélectriques équations constitutives, et le principe de variation de Hamilton sont développés. Un C0 continue, cisaillement flexible, à huit nuds élément de coque à double courbure sérendipité pour les plaques piézocomposites stratifiés et de coquillages est également dérivée basée sur la théorie de la couche-sage déformation de cisaillement, linéaires piézo-électriques couplés relations constitutives mécaniques, et le principe de variation de Hamilton. Toute la poutre, plaque, et des éléments de coque développés ont considéré la rigidité, de masse et les effets de couplage électromécanique du capteur piézo-électrique et les couches de l'actionneur. Les éléments de structure développéssont capables de traiter les effets non linéaires de déformation en cisaillementtransversal et la non-linéarité des matériaux composites, piézoélectrique-mécanique d'accouplement, et peut prévoir plus précisément les modes supérieurs de vibration, et peut être appliquée à partir de minces d'épaisseur moyenne structures composites multicouches. Ils sont évalués à la fois les vibrations et analyse de flambage de la poutre, plaque, et structures en coque. La partie de commande actif : La vibration de supprimer d'un porte à faux piézo-collé poutre, les deux premiers modes de flambement contrôle d'un appui simple piézo-collé poutre, et la vibration et le flambage contrôle de la charge d'un cantilever piézoélectrique stratifié plaque composite sont étudiés. Les résultats de l'analyse par éléments finis sont utilisés pour concevoir un régulateur linéaire quadratique (LQR) contrôleur et un linéaire quadratique gaussienne (LQG) compensateur avec un observateur d'état dynamique pour atteindre toutes les commandes. Les conceptions de commandes commencent par une méthode modale modle pour déterminer un modle modal réduit approximative qui peut représenter la dynamique du systme avec les modes les moins systme inclus. Un modle modal espace d'état de la structure intelligente qui a intégré la structure d'accueil d'colléscapteurs et d'actionneurs piézoélectriques, est ensuite utilisé pour concevoir le systme de contrôle. Les contrôles visant commentaires LQR/LQG sont avérés succs dans la suppression de la vibration et de stabiliser les modes de flambement des structures. Tant l'analyse par éléments finis et les résultats de simulation de contrôle actives sont compatibles avec les résultats existants d'analyse théoriques et les données expérimentales de la littérature. Quelques conclusions importantes et des observations intéressantes sont obtenues.
Tehrani, Maryam Ghandchi. "Passive modification and active vibration control by receptance method". Thesis, University of Liverpool, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441935.
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