This article present a modelling method well adapted to the study of brushless permanent magnet m... more This article present a modelling method well adapted to the study of brushless permanent magnet machines used in high speed drives. One of the major issues of the proposed technique lies on the possibility of taking into account the induced currents flowing in the conductive parts of the machine. So the basic principles and the validation of this method were
2008 18th International Conference on Electrical Machines, 2008
This article deals with the presentation of an experimental bench dedicated to the teaching of el... more This article deals with the presentation of an experimental bench dedicated to the teaching of electromechanical systems during undergraduate curriculum. This bench permits to explain the main principles of an elementary synchronous motor by a practical approach of the physical phenomena. At first, students start to describe theoretically the motor based on the fundamental electromagnetic relations and concretise their calculations by a progressive realization of their coil windings and finally the electromechanical characterization of the motor. The educational approach is done in order to bring students to face with essential questions about machines and electrical drives.
ABSTRACT The purpose of this article is to show the advantage of a deterministic global optimizat... more ABSTRACT The purpose of this article is to show the advantage of a deterministic global optimizationmethod in the optimal design of electromechanical actuators. The numerical methods classically usedare found either on Non-linear Programming techniques (Augmented Lagrangian, Sequential QuadraticProgramming, ...) or on stochastic approaches which are more satisfactorily adapted to global optimumresearch (Genetic Algorithm, Simulated Annealing, ...). However, these kinds of methods only guaranteeto...
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2000
This paper deals with a deterministic and rational way to design piezoelectric transformers in ra... more This paper deals with a deterministic and rational way to design piezoelectric transformers in radial mode. The proposed approach is based on the study of the inverse problem of design and on its reformulation as a mixed constrained global optimization problem. The methodology relies on the association of the analytical models for describing the corresponding optimization problem and on an exact global optimization software, named IBBA and developed by the second author to solve it. Numerical experiments are presented and compared in order to validate the proposed approach.
The European Physical Journal Applied Physics, 2002
This article proposes a methodology of design adapted to the optimal dimensioning of piezoelectri... more This article proposes a methodology of design adapted to the optimal dimensioning of piezoelectric actuators. The study relates to a heterogeneous bimorph bar working in bending quasi-static mode. First an analytical model of the bimorph is established on the basis of classically allowed assumptions in theory of the beams and piezoelectricity. The field of validity of this model is then specified by comparison with a computer code by finite elements. Moreover the results obtained are validated and refined using measurements realised on a model of bimorph. The developed model is then exploited within a procedure of automated dimensioning founded on the implementation of a new method of Global Optimization. The possibilities of the developed method are finally illustrated through the dimensioning of a particular piezoelectric actuator intended for a vibratory magnetometric equipment.
The European Physical Journal Applied Physics, 1999
ABSTRACT This article deals with a general method for finding the equations of the dynamic respon... more ABSTRACT This article deals with a general method for finding the equations of the dynamic response of a bimorphous piezoelectric structure through a variational formulation. First, a method of resolution is proposed then a general electric equivalent circuit involving the design parameters of the device is deduced, followed by the description of application to a travelling-wave stator.
COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 2003
ABSTRACT What is new in this work is the generic capabilities of the proposed analytical model of... more ABSTRACT What is new in this work is the generic capabilities of the proposed analytical model of permanent magnet machines associated with a novel deterministic global optimization method. That allows to solve some more general inverse problem of designing. The analytical approach is powerful to take into account various kinds of constraints (electromagnetical, thermal, etc.). The inverse problem associated with the optimal design of actuators could then be formulated as a mixed-constrained optimization problem. In order to solve these problems, interval Branch and Bound algorithms which have already proved their efficiency, have made it possible to determine some optimized rotating machines.
ABSTRACT Coherent structures play an important role in the dynamics of turbulent and transitionna... more ABSTRACT Coherent structures play an important role in the dynamics of turbulent and transitionnal boundary layer. The ability to control these coherent structures could be significant in the way of reducing skin friction, delaying transition and separation point. The use of new techniques can involve benefits in many industries. This work aims at finding efficient means to reduce skin friction drag in a turbulent boundary layer. The central elements of this self-sustaining cycle are the near-wall coherent structures whose dynamics control the turbulence and Reynolds shear stress production and is maintained even in the absence of forcing from the free-stream. Quasi-streamwise vortices and streaks of low and high-speed involve a secondary instability mechanism. Time and length scales of these structures have been displayed and are usually given in wall units. Direct numerical simulations in a turbulent channel flow have shown that a transverse traveling wave could suppress this cycle and allow a 30% global skin friction reduction for well-chosen wave parameters. Streaks intensity are weakened and they merge together. This study is focused on the experimental realisation of this control technique: the mass force of the simulations is replaced by a "smart" moving wall generating the spanwise wave. Velocity and skin friction measurements will be carried out on the modified flow to determine the expected gain on drag reduction and deal with the secondary instability mechanism. A model cycle is produced by embedding artificial, large scale streamwise vortices and streaks in a Blasius boundary layer. The controllers in the present macroscopic simulation are simply cantilever beams whose movement is driven by ceramic piezo-actuators. The control on a turbulent boundary layer will be then attempted. Results will be presented for the conference.
2011 10th International Workshop on Electronics, Control, Measurement and Signals, 2011
A linear tubular switched reluctance motor is presented. This actuator is devoted to be used as a... more A linear tubular switched reluctance motor is presented. This actuator is devoted to be used as a left ventricular assist device (LVAD). In order to avoid thrombosis, this actuator includes pump and valve functions. By using a St. Jude Medical mechanical valve inside the tubular mover, a pulsatile flow is created in the descending aorta. A linear model of a basic pattern of the actuator based on a reluctance network is developed. Then, a two dimensions finite element method analysis is performed in order to check the analytically calculated performances. Relying on these both models, specific requirements for the design of this kind of motor are discussed.
ABSTRACT Résumé : Dans le domaine des actionneurs de dimension centimétrique à fort couple et bas... more ABSTRACT Résumé : Dans le domaine des actionneurs de dimension centimétrique à fort couple et basse vitesse, les moteurs piézoélectriques constituent aujourd'hui des produits aux fonctionnalités très attractives. Couple massique élevé, verrouillage naturel hors alimentation, discrétion acoustique, excellente dynamique, autant de points forts qui ont largement contribué au développement de ce type d'actionneurs dans des domaines très variés tels que la domotique, l'optique, l'aéronautique, le spatial voire le génie bio-médical. Il apparaît dans ce contexte, intéressant voire incontournable d'aborder dans le cycle de la formation GEA les principes de fonctionnement de ce type d'actionneur ainsi que la métrologie très appropriée qui lui est rattachée. Mots clés : Actionneur piézoélectrique, onde progressive, vibromètre LASER, contact, structure résonante. 1 INTRODUCTION L'objectif de ce TP consiste, d'une part, à appréhender le fonctionnement des actionneurs piézoélectriques à onde progressive par l'approche des caractéristiques couple/vitesse et des principales lois de fonctionnement qui lui sont propres et d'autre part à se familiariser avec une métrologie de pointe et de précision inhérente à l'étude des déformations micrométriques générées au sein d'une structure mécanique déformable.
2008 18th International Conference on Electrical Machines, 2008
ABSTRACT This article present a modelling method well adapted to the study of brushless permanent... more ABSTRACT This article present a modelling method well adapted to the study of brushless permanent magnet machines used in high speed drives. The issue of the proposed technique lies on the possibility of taking into account the induced currents flowing in the conductive parts of the machine. This modelling integrates different type of rotor and stator current density. So the basic principles and the validation of this method were given in this paper.
83 Boulevard de l'hôpital, 75013 Paris llibre@laplace.univ-tlse.fr ; nogarede@laplace.univ-tl... more 83 Boulevard de l'hôpital, 75013 Paris llibre@laplace.univ-tlse.fr ; nogarede@laplace.univ-tlse.fr Sections de rattachement : 63 Secteur : Secondaire RÉSUMÉ. Nous proposons un nouveau concept de dispositif d'assistance circulatoire mécanique ventriculaire gauche (LVAD) positionné sur l'aorte descendante, appelé Pulsamag. Dans le but d'éviter l'apparition de thrombose, cette pompe pulsatile intègre la fonction pompe et valve. Un démonstrateur a été conçu et est basé sur un actionneur tubulaire linéaire à réluctance variable. L'intérieur du translateur tubulaire est équipé d'une valve aortique de 25 mm de diamètre permettant ainsi la circulation du sang. Les caractéristiques de l'actionneur sont déterminées à partir d'un modèle théorique linéaire et d'une étude par simulation à l'aide d'un logiciel de calcul de champs par éléments finis. MOTS-CLÉS : assistance circulatoire, pompe pulsatile, valve, réluctance variable, actionneur linéaire.
This article present a modelling method well adapted to the study of brushless permanent magnet m... more This article present a modelling method well adapted to the study of brushless permanent magnet machines used in high speed drives. One of the major issues of the proposed technique lies on the possibility of taking into account the induced currents flowing in the conductive parts of the machine. So the basic principles and the validation of this method were
2008 18th International Conference on Electrical Machines, 2008
This article deals with the presentation of an experimental bench dedicated to the teaching of el... more This article deals with the presentation of an experimental bench dedicated to the teaching of electromechanical systems during undergraduate curriculum. This bench permits to explain the main principles of an elementary synchronous motor by a practical approach of the physical phenomena. At first, students start to describe theoretically the motor based on the fundamental electromagnetic relations and concretise their calculations by a progressive realization of their coil windings and finally the electromechanical characterization of the motor. The educational approach is done in order to bring students to face with essential questions about machines and electrical drives.
ABSTRACT The purpose of this article is to show the advantage of a deterministic global optimizat... more ABSTRACT The purpose of this article is to show the advantage of a deterministic global optimizationmethod in the optimal design of electromechanical actuators. The numerical methods classically usedare found either on Non-linear Programming techniques (Augmented Lagrangian, Sequential QuadraticProgramming, ...) or on stochastic approaches which are more satisfactorily adapted to global optimumresearch (Genetic Algorithm, Simulated Annealing, ...). However, these kinds of methods only guaranteeto...
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2000
This paper deals with a deterministic and rational way to design piezoelectric transformers in ra... more This paper deals with a deterministic and rational way to design piezoelectric transformers in radial mode. The proposed approach is based on the study of the inverse problem of design and on its reformulation as a mixed constrained global optimization problem. The methodology relies on the association of the analytical models for describing the corresponding optimization problem and on an exact global optimization software, named IBBA and developed by the second author to solve it. Numerical experiments are presented and compared in order to validate the proposed approach.
The European Physical Journal Applied Physics, 2002
This article proposes a methodology of design adapted to the optimal dimensioning of piezoelectri... more This article proposes a methodology of design adapted to the optimal dimensioning of piezoelectric actuators. The study relates to a heterogeneous bimorph bar working in bending quasi-static mode. First an analytical model of the bimorph is established on the basis of classically allowed assumptions in theory of the beams and piezoelectricity. The field of validity of this model is then specified by comparison with a computer code by finite elements. Moreover the results obtained are validated and refined using measurements realised on a model of bimorph. The developed model is then exploited within a procedure of automated dimensioning founded on the implementation of a new method of Global Optimization. The possibilities of the developed method are finally illustrated through the dimensioning of a particular piezoelectric actuator intended for a vibratory magnetometric equipment.
The European Physical Journal Applied Physics, 1999
ABSTRACT This article deals with a general method for finding the equations of the dynamic respon... more ABSTRACT This article deals with a general method for finding the equations of the dynamic response of a bimorphous piezoelectric structure through a variational formulation. First, a method of resolution is proposed then a general electric equivalent circuit involving the design parameters of the device is deduced, followed by the description of application to a travelling-wave stator.
COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, 2003
ABSTRACT What is new in this work is the generic capabilities of the proposed analytical model of... more ABSTRACT What is new in this work is the generic capabilities of the proposed analytical model of permanent magnet machines associated with a novel deterministic global optimization method. That allows to solve some more general inverse problem of designing. The analytical approach is powerful to take into account various kinds of constraints (electromagnetical, thermal, etc.). The inverse problem associated with the optimal design of actuators could then be formulated as a mixed-constrained optimization problem. In order to solve these problems, interval Branch and Bound algorithms which have already proved their efficiency, have made it possible to determine some optimized rotating machines.
ABSTRACT Coherent structures play an important role in the dynamics of turbulent and transitionna... more ABSTRACT Coherent structures play an important role in the dynamics of turbulent and transitionnal boundary layer. The ability to control these coherent structures could be significant in the way of reducing skin friction, delaying transition and separation point. The use of new techniques can involve benefits in many industries. This work aims at finding efficient means to reduce skin friction drag in a turbulent boundary layer. The central elements of this self-sustaining cycle are the near-wall coherent structures whose dynamics control the turbulence and Reynolds shear stress production and is maintained even in the absence of forcing from the free-stream. Quasi-streamwise vortices and streaks of low and high-speed involve a secondary instability mechanism. Time and length scales of these structures have been displayed and are usually given in wall units. Direct numerical simulations in a turbulent channel flow have shown that a transverse traveling wave could suppress this cycle and allow a 30% global skin friction reduction for well-chosen wave parameters. Streaks intensity are weakened and they merge together. This study is focused on the experimental realisation of this control technique: the mass force of the simulations is replaced by a "smart" moving wall generating the spanwise wave. Velocity and skin friction measurements will be carried out on the modified flow to determine the expected gain on drag reduction and deal with the secondary instability mechanism. A model cycle is produced by embedding artificial, large scale streamwise vortices and streaks in a Blasius boundary layer. The controllers in the present macroscopic simulation are simply cantilever beams whose movement is driven by ceramic piezo-actuators. The control on a turbulent boundary layer will be then attempted. Results will be presented for the conference.
2011 10th International Workshop on Electronics, Control, Measurement and Signals, 2011
A linear tubular switched reluctance motor is presented. This actuator is devoted to be used as a... more A linear tubular switched reluctance motor is presented. This actuator is devoted to be used as a left ventricular assist device (LVAD). In order to avoid thrombosis, this actuator includes pump and valve functions. By using a St. Jude Medical mechanical valve inside the tubular mover, a pulsatile flow is created in the descending aorta. A linear model of a basic pattern of the actuator based on a reluctance network is developed. Then, a two dimensions finite element method analysis is performed in order to check the analytically calculated performances. Relying on these both models, specific requirements for the design of this kind of motor are discussed.
ABSTRACT Résumé : Dans le domaine des actionneurs de dimension centimétrique à fort couple et bas... more ABSTRACT Résumé : Dans le domaine des actionneurs de dimension centimétrique à fort couple et basse vitesse, les moteurs piézoélectriques constituent aujourd'hui des produits aux fonctionnalités très attractives. Couple massique élevé, verrouillage naturel hors alimentation, discrétion acoustique, excellente dynamique, autant de points forts qui ont largement contribué au développement de ce type d'actionneurs dans des domaines très variés tels que la domotique, l'optique, l'aéronautique, le spatial voire le génie bio-médical. Il apparaît dans ce contexte, intéressant voire incontournable d'aborder dans le cycle de la formation GEA les principes de fonctionnement de ce type d'actionneur ainsi que la métrologie très appropriée qui lui est rattachée. Mots clés : Actionneur piézoélectrique, onde progressive, vibromètre LASER, contact, structure résonante. 1 INTRODUCTION L'objectif de ce TP consiste, d'une part, à appréhender le fonctionnement des actionneurs piézoélectriques à onde progressive par l'approche des caractéristiques couple/vitesse et des principales lois de fonctionnement qui lui sont propres et d'autre part à se familiariser avec une métrologie de pointe et de précision inhérente à l'étude des déformations micrométriques générées au sein d'une structure mécanique déformable.
2008 18th International Conference on Electrical Machines, 2008
ABSTRACT This article present a modelling method well adapted to the study of brushless permanent... more ABSTRACT This article present a modelling method well adapted to the study of brushless permanent magnet machines used in high speed drives. The issue of the proposed technique lies on the possibility of taking into account the induced currents flowing in the conductive parts of the machine. This modelling integrates different type of rotor and stator current density. So the basic principles and the validation of this method were given in this paper.
83 Boulevard de l'hôpital, 75013 Paris llibre@laplace.univ-tlse.fr ; nogarede@laplace.univ-tl... more 83 Boulevard de l'hôpital, 75013 Paris llibre@laplace.univ-tlse.fr ; nogarede@laplace.univ-tlse.fr Sections de rattachement : 63 Secteur : Secondaire RÉSUMÉ. Nous proposons un nouveau concept de dispositif d'assistance circulatoire mécanique ventriculaire gauche (LVAD) positionné sur l'aorte descendante, appelé Pulsamag. Dans le but d'éviter l'apparition de thrombose, cette pompe pulsatile intègre la fonction pompe et valve. Un démonstrateur a été conçu et est basé sur un actionneur tubulaire linéaire à réluctance variable. L'intérieur du translateur tubulaire est équipé d'une valve aortique de 25 mm de diamètre permettant ainsi la circulation du sang. Les caractéristiques de l'actionneur sont déterminées à partir d'un modèle théorique linéaire et d'une étude par simulation à l'aide d'un logiciel de calcul de champs par éléments finis. MOTS-CLÉS : assistance circulatoire, pompe pulsatile, valve, réluctance variable, actionneur linéaire.
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