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International audience; Multiple-Input/Multiple-Output (MIMO) techniques have recently become an important research field for enhancing the performance of in-home Power Line Communication (PLC) systems by exploiting the additional Protective Earth wire. The development of such systems requires an accurate description of the channel noise. In this paper we have presented a model for PLC background noise based on an extensive set of measurements. We have adopted the framework of multivariate time series to model the PLC background noise.This paper employs the Vector Autoregressive (VAR) modeling technique to extract noise model parameters from the measured noise. We have verified the accuracy of the noise model by comparing time and frequency domain correlation of measured and modeled noises.

International audience; In this paper, the authors describe a modeling and design method for a permanent magnet drive used in a power train for Hybrid Electric Heavy Vehicle, based on a Series-Parallel architecture. The hybrid powertrain structure enables high requirements for boost mode of acceleration and full electric mode. A 'Ravigneaux' train was integrated in this hybrid powertrain structure in order to split energy among the vehicle wheels, the thermal engine, the electrical motor and the alternator. To compare the classical simple epicyclic train used in series-parallel Toyota hybrid structure, this 'Ravigneaux' train developed by Nexter group presents a better adaptation to high mechanical constraints (high power and torque) because of its double stages compound structure. Several operation modes of vehicle were analyzed by assuming that the two electrical machines were identical and reversible (they can both operate as a motor or an alternator). In this paper, a simple drive is considered: it deals with a Surface-Mounted Permanent Magnet Synchronous Machine (SMPMSM) and a two level Voltage Source Inverter (VSI). An analytical modeling based on three working points: boost working point, nominal working point and maximal rotation speed working point has been elaborated. The analytical modeling makes it possible to model the physical behavior of different components. It enables to analyze quickly the relationship between the different parameters. A numerical modeling using 2D finite elements is also presented in this paper. The aim of 2D finite elements analysis (2DFEA) is to validate the machine performances obtained by analytical modeling. It enables to model some physical phenomena with a better accuracy, such as magnetic saturation. Generally, the results given by 2DFEA will be closer to experimental results. The control law of the electrical machine was investigated by the way of a single-phased electromechanical modeling. With this model, the flux weakening analysis has been taken into account in order to adapt the motor winding according to the rotation speeds defined in the specifications. The flux weakening was realized by considering mechanical and electrical characteristics linked with power, torque, rotation speed, DC-link voltage, feeding voltage of electrical machine, Id and Iq currents, cyclic inductance, winding resistance, back-electromotive force, phase difference between back electromotive force and phase current... The electrical machine losses have been calculated by neglecting the mechanical losses and PM losses. The machine losses calculation includes the copper losses and the iron losses (eddy currents losses and hysteresis losses). The flux density in the stator yoke and the teeth was evaluated by taking into account the magnetic flux created by permanent magnet and the one created by armature reaction (stator current). The inverter losses were calculated too, by considering the commutation and conduction losses of both diodes and IGBT transistors. Thus, the total losses and the global efficiencies of motor and inverter were evaluated and the best working points can be deduced from those calculations. The previous models enable to evaluate global energy performances of electrical machines and inverters by respecting the constraints defined in the specifications. This methodology is general and can be a first step of a complete power train optimal design, including the electrical drive, the gear, the energy storage units and possibly the internal combustion engine.

This paper deals with systematically applying a modern principle of designing real-time simulators, namely the HILS (hardware-in-the-loop simulation) concept, consisting in closed-loop connecting physical and software parts, in order to replicate in laboratory conditions the dynamic behaviour of an industrial process. The software part results from modelling the real system to be simulated, whereas the physical part is taken as it is from this system. Principles of HILS systems are first presented, then a systematic design procedure is proposed and illustrated by building a simulator dedicated to variable-speed wind energy conversion systems. The architecture and possibilities of this simulator are suggested by amply discussing the most relevant experimental results. Some concluding remarks finish this paper.

VTHD is a high-performance IP experimental network. This network and associated research projects have been partially funded by the French government through the French Research Network for Telecommunications (RNRT) in order to support the development of leading-edge network services on the one hand, and test a wide-scale deployment of advanced Internet applications on the other hand. This paper describes the network services that were deemed necessary to support the deployment of innovative applications are described, as well as several of the applications that have been experimented on the network. It also presents a selection of the traffic engineering methods and experiments that have been developed in the course of the VTHD related research projects. This article describes the collective works of members of the project partners, which are represented here by the paper's co-authors., VTHD est un réseau IP expérimental à très haut débit. Ce réseau et les projets de recherche associés ont reçu un financement public par l'intermédiaire du Réseau National de Recherche en Télécommunications (RNRT) dans le but de permettre à la communauté scientifique française de développer des services réseau innovants et de tester le déploiement à grande échelle d'applications Internet avancées. Cet article décrit les services réseau nécessaires pour supporter le déploiement d'applications innovantes, ainsi que les applications qui ont été expérimentées sur le réseau VTHD. Enfin, l'article présente une sélection des méthodes et des expérimentations en matière d'ingénierie de trafic développées lors des projets de recherche associés à VTHD. Cet article décrit les travaux réalisés collectivement par de nombreux membres des institutions partenaires, qui sont représentées ici par les auteurs cosignant l'article.

International audience; In this paper, we discuss the control and suppression of spurious resonances commonly encountered with distributed bandpass filters. The basic idea consists of introducinglow-pass structures within bandpass topologies. By adjusting low-pass filter cutoff frequencies, harmonic resonances are attenuated, while maintaining in-band performances. In addition, transmission losses may be reduced as the insertion technique leads to optimum designs in terms of overall size. The approach described here is based upon the combination of classical synthesis techniques and optimization proceduresprovided by conventional computer-aided-design tools. Experimental results are obtained in the case of /spl lambda//sub g//4 shunt-stub filters implemented in classical semilumped low-pass architectures. Then, we investigate alternative integration technologies and techniques to improve the out-of-band rejection over very wide operating bandwidth. To overcome some design limitations, i.e., workable characteristicimpedance value, we propose and validate a multilayer solution. Finally, new low-pass topologies are suggested to improve low-pass filter band rejection.; In this paper, we discuss the control and suppression of spurious resonances commonly encountered with distributed bandpass filters. The basic idea consists of introducinglow-pass structures within bandpass topologies. By adjusting low-pass filter cutoff frequencies, harmonic resonances are attenuated, while maintaining in-band performances. In addition, transmission losses may be reduced as the insertion technique leads to optimum designs in terms of overall size. The approach described here is based upon the combination of classical synthesis techniques and optimization proceduresprovided by conventional computer-aided-design tools. Experimental results are obtained in the case of /spl lambda//sub g//4 shunt-stub filters implemented in classical semilumped low-pass architectures. Then, we investigate alternative integration technologies and techniques to improve the out-of-band rejection over very wide operating bandwidth. To overcome some design limitations, i.e., workable characteristicimpedance value, we propose and validate a multilayer solution. Finally, new low-pass topologies are suggested to improve low-pass filter band rejection.

In this paper, a study of an autonomous hybrid PV-Wind-battery system for a residential house of 4 persons in La Rochelle in France is presented. It includes system design optimization and performance evaluation in addition of its economic and environmental life cycle analysis. The results show a low environmental impact and a reasonable economic cost of the system.

National audience; The development of micro and nanotechnologies requires the design of microrobots and Microsystems able to handle submillimetric objects. Many micromanipulation systems have been built. However, improvement of the performances requires the use of advanced control methods. In this paper, we present the main characteristics of the microworld from a control point of view and some control strategies adapted to the microsystems.

International audience; Basé sur la théorie du contrôle par supervision (TCS), nous proposons une démarche d'aide à l'étude de la dynamique des Systèmes à Événements Discrets (SED). Située en amont du cycle de conception des lois de commande des SED, notre proposition concerne la gestion des modes de fonctionnement. L'objectif est de permettre tout d'abord l'étude formelle de la dynamique du système contrôlé dans chaque mode puis celle de la succession de ces dynamiques. Dans cet article nous insisterons particulièrement sur la présentation des différentes étapes de construction et de génération automatique des modèles ainsi que sur les possibilités de validation de ceux-ci. Based on the Supervisory Control Theory, this paper introduces a framework to help study the dynamics of Discrete Event Systems (DES). Upstream of the design process of control law in DES, the proposal focuses on the management modes of operation. The goal is to first allowing a formal study of the controlled system's dynamics in each mode and secondly studying the mode switching. This article is focused on the presentation of the different stages of design, the automatic generation of models and the possibilities of validating them.

This paper describes the design and the placement of piezoelectric actuators on switched reluctance motors by means of a genetic algorithm (nondominated sorting genetic algorithm II) for the purpose of reducing stator vibrations. Two distinct approaches are presented: one energy-related and the other based on a minimization of the resultant displacement. These methods lead to design and placement strategy for the piezoelectric actuators. A number of optimal actuators obtained using these kinds of approaches is also compared with mechanical finite-element simulations. At last, a solution is achieved in order to validate optimal placement using positive position feedback active filtering.

This paper presents an original design option dedicated to output-filtered pulsewidth modulation inverters used in uninterruptible power systems, embedded networks, or motor drives operating on long cables. It is based on the coupling of interleaved inverter cells by means of intercell transformers (ICTs) and is characterized by very good dynamic behavior on load transients, which is an important issue in such applications. ICT solutions are compared with the classical interleaved solutions using separate inductors. A specific design method is developed to achieve this comparison based on toroidal core shapes. The results obtained with a 600 V, 7.5 kW inverter show the usefulness of ICT-based designs, especially when nanocrystalline magnetic material is used; high specific power and very good dynamic performances are obtained.

National audience; This paper presents a steering assistance system that prevents unintended lane departures. The assistance intervenes only when the driver is inattentive and the vehicle is about to leave the lane. Road curvatures represent a challenge for the control law concerning the lane keeping performance as well as the lane overshoot in the case of activation in curves. To address these issues, the control law has been designed by using invariant sets theory and bilinear matrix inequalities optimization methods. Field tests have shown the theoretical expectations to be fulfilled and have demonstrated the high robustness properties of the implemented control law.

International audience; The main goal of Fault Tolerant Control Systems (FTCS) is to preserve the ability of the system to achieve the objectives that has been assigned when faults or failures occurred. The main goal of this work is to develop a fault tolerant control strategy that incorporates both reliability and dynamic performance of the system for control reconfiguration. Once a fault has been detected and isolated, the reconfiguration strategy proposed in this paper tries to find possible structures of the faulty system that preserve prespecified performance, calculate the system reliability, compute new controller gains and finally search the optimal structure that has the "best" control performance with the highest reliability. The proposed approach is illustrated through a hydraulic and thermal system of three tanks.

In this paper we propose a control scheme based on Coloured Petri net (CPN) for a flow-rack automated storage and retrieval system. The AS/RS is modelled using Coloured Petri net. The developed model is used to capture and provide the rack state. We introduce in the control system an optimization module as decision process which performs a real-time optimization working on discrete events time scale. The objective is to find bin locations for the retrieval requests by minimizing the total number of retrieval cycles for a batch of requests and thereby increase the system throughput. By solving the optimization model, the proposed method gives according to customers request and the rack state, the best bin locations for retrieval, i.e. allowing at the same time to satisfy the customers request and carrying out the minimum of retrieval cycles.

This paper presents a virtual reality environment for the design and simulation of transitic systems. This framework is called SimSED (Simulation of Discrete Event Systems). The objective is to test and validate the control code of the system before on-site implementation. The control code is validated by joint simulation of the transitic system's material part and control part. The system is validated according with a set ofscenarii. The virtual reality environment provides a tool for representing a transitic system in three dimensions, which encapsulates the dynamic behavior of the system. The applications developed by using this framework are also presented.

Safety verification and reachability for hybrid systems is a very active research domain. Many approaches that seem quite different, have been proposed to solve this complex problem and this paper presents a synthesis of these various approaches with respect to basic problems related to verification of hybrid systems.

The paper considers the problem ofscheduling jobs on parallel human resources. The nature of resources increases the complexity of the task since individual skills and efficient utilization of the operators have to be managed with the flow time reduction. A model of the problem and mono-criterion optimizations are proposed with various scheduling objectives: minimization of the workload fulfillment, polyvalence keeping and equitable utilization of resources.

The air-handling units (AHUs) provide complete control of temperature and humidity in air-conditioned spaces. The models of the AHU elements are nonlinear and the controlled variables, temperature and relative humidity, coupled. This paper demonstrates that in the case of sensible heat exchange without moisture removal if the outputs of the electric coils, fluid-filled coils and steam humidifiers of an AHU are considered to be the differences between the air temperature and the humidity ratio of the outlet and the inlet, then the models may be written as the product of a static and a dynamic gain. The parameters of the discrete form of these models are experimentally identified. The dynamics of the elements and of their sensors are very similar. Therefore, the parameter identification of the elements takes into account the model of the sensor, previously identified. This grey-box approach combines theoretical modelling, parameter identification of discrete models and parameter identification of partially known models by using optimization techniques.

International audience; In this paper, we derive mathematical expressions to assess reliability importance measures for a component in a common cause failure group (CCF). The main originality of this work is that the existing information on the cause of the component unavailability (intrinsic, unknown, CCF-related, maintenance) can be explicitly taken into account in the importance factor computation.; Cet article a pour objet de présenter des expressions permettant de calculer les facteurs d’importance fiabilistes d’un composant appartenant à un groupe de défaillance de cause commune (DCC). La possibilité de prendre en compte l’information sur la nature de la défaillance du composant considéré (intrinsèque, origine non identifiée, DCC, maintenance) lors du calcul des facteurs d’importance constitue la principale originalité de l’approche proposée

In this paper, we propose an evolution of adaptive power control algorithms for Universal Mobile Telecommunications System (UMTS). The proposed mechanism uses an adaptive power step to carry out with high fluctuations in the radio interface. Furthermore, we propose the integration of a stabilization zone where the transmitted power is kept constant to reduce oscillations around the target QoS level. In this algorithm, only the interpretation of power control feedback commands is ameliorated by adding some intelligence to mobiles and base stations. Moreover, the standardized radio interface protocol is used without modification. The algorithm can be used in both link directions of the Frequency Division Duplex (FDD) mode and in the downlink of the Time Division Duplex (TDD) mode, where closed- loop power control algorithms are used. Simulation results show that the proposed algorithm decreases the outage probability and reduces drastically the transmitted power, which are the main objectives of power control algorithms., Dans cet article, nous proposons une évolution originale de la commande de puissance normalisée pour les systèmes mobiles de troisième génération (UMTS: Universal Mobile Telecommunications System). Le mécanisme proposé utilise des pas adaptatifs pour résoudre le problème de variations brusques mais importantes dans l?interface radio. Notre proposition consiste à intégrer une zone de stabilisation de qualité de service (QoS) dans laquelle la puissance émise est maintenue constante. Cette stabilisation de puissance mène à une réduction des oscillations autour du niveau de QoS désiré. Cet algorithme entraîne seulement un changement d?interprétation des commandes mais aucune modification du protocole normalisé de l?interface radio. L?algorithme peut être utilisé dans les deux sens de transmission des systèmes à duplexage fréquentiel (FDD) et sur la voie descendante des systèmes à duplexage temporel (TDD). Les résultats des simulations montrent que l?algorithme proposé diminue d?une manière importante le taux d?insatisfaction des utilisateurs et minimise la puissance émise.

This paper presents the results on the modeling and the control of a two-wheeled prototype, the vehicle named B2, based on the inverted pendulum principle. Its goal is to reduce the problems due to the vehicles in the center of the towns. A Takagi-Sugeno fuzzy model has been developed from the prototype parameters. Some robust PDC control laws, with and without observers were realized in continuous time. A comparison with a linear law and some robustness tests were presented. The results are satisfactory, the B2 is stabilized and the speed follow s the state point given by a joystick.; Cet article présente des résultats sur la modélisation et la commande d'un prototype de véhicule à 2 roues nommé le B2, basé sur le principe du pendule inversé.

International audience; Web technologies are more and more used in the supervision and control-command domains, but are poor used to make remote control on the Internet. In this paper, we first present remote control experiences of mechanical systems. We then propose a software architecture and a gemma-like method to take into account the lack of quality of services of Internet. We conclude, presenting applications developped in the laboratory and measurements made on the actual quality of the network, showing the feasability of remote control.; Les technologies du Web prennent de plus en plus de place dans le domaine de la supervision et du contrôle-commande, mais ne sont que très peu utilisées pour permettre un contrôle distant sur le réseau internet. Dans cet article, nous présentons d'abord des expériences de contrôle à distance de systèmes mécaniques. Nous proposons ensuite une architecture logicielle et une méthode orientée Gemma pour prendre en compte le manque de qualité de service de l'internet au sens large. Nous concluons en présentant des applications dévéloppées au laboratoire ainsi que des résultats de mesure sur la qualité actuelle du réseau, qui démontrent la faisabilité du contrôle distant.

International audience; In this paper we focus on the replanning process of a single project which uses unitary, undivisible resources that are considered critical. Because of other projects or other companies, those ressources are booked on several time-windows. From an inital problem definition, at the beginning of the project, the planning work essentially consists in updating the problem definition itself, during all of the project life, when unfeasibility arises due to disturbances. More over the multi-project is also to be considered through the booked resources constraints. We propose a decision support system, tested on an industrial case, for a project manager, which incorporates the constraints of the booked resources due to the multi-project and multi-company context. This system displays explanations for problem inconsistency likely to help the decision-maker to restore consistency and proposes a solution to the project-scheduling problem when the consistency has been restored.; Dans cet article, on s'intéresse à la planification d'un projet nécessitant des ressources unitaires, non divisibles et jugées critiques qui, sur certains créneaux de temps, ont déjà été réservées par d'autres projets ou d'autres entreprises. A partir d'une expression initiale d'un réseau d'activités, le rôle d'un responsable de la planification est soit de fournir un ordonnancement réalisable de ces activités, soit de redéfinir le réseau pour pouvoir trouver ensuite un ordonnancement réalisable. Dans ce cadre, nous proposons un outil d'aide à la replanification, dont le prototype a été testé sur une application industrielle, destiné au responsable d'un projet en intégrant les contraintes de réservation de ressources liées au contexte multiprojet, multi-entreprise. Cet outil intègre une méthode qui, lorsque le problème est incohérent, exhibe les causes de cette incohérence et lorsque la cohérence a été restaurée propose une solution au problème d'ordonnancement.

In this paper we focus on anaerobic digestion in a continuous bioreactor, a high yield waste water treatment process but which is intrinsequely unstable. After a brief description of the underlying model, based on two main steps (acidogenesis and methanogenesis), we propose a control law allowing to choose organic pollution level (Chemical Oxigen Demand, COD) inside a continuous anaerobic digester. This globally asymptotically stabilising control law, regulates a biologically based measurement of organic pollution. The closed loop system behavior is then illustrated on a noisy simulation and finally validated on a real life pilot process.

In this paper, we present a waveform converter implemented on a 0.25-/spl mu/m CMOS technology using a dedicated design methodology (Delay Oriented Design). The circuit converts a square wave signal in both in-phase and quadrature-phase sinusoidal differential outputs. It also multiplies the frequency by seven. The output frequency range of this converter extends from 1.05 GHz up to 2.17 GHz. This converter is dedicated for the design of a third-generation mobile phone synthesizer using a double-loop architecture. For an output frequency of 2 GHz, the measured phase noise at 10-kHz offset from the carrier is -97 dBc/Hz. The circuit consumes 50 mW from a 2.5-V supply.

This paper investigates the absorbing layer techniques for three-dimensional transmission-line matrix (3d-tlm) simulations. Applications are the full-wave analysis of structures such as microwave and millimeter-wave circuits open to free space. Two approaches are presented, namely the matched layer (ml) and the perfectly matched layer (pml) technique which is used for general cases. For the ml technique, which is efficient for matching guides operating in a quasi-TEM condition, a comparison of the different tlm condensed node is carried out. Concerning the more general case of the pml technique, the theoretical development of a new general three-dimensional (3d) tlm condensed cell is presented. Results pertaining to the characterization of planar circuits are compared with other solutions or measurements. It is found that a proposed unified approach, which includes the tlm simulation for matched layer media, yields very good performance in terms of the absorbing boundary condition (abc).

A computer-aided design (CAD) procedure based on the real-frequency technique (RFT) is introduced for treating the matching of an arbitrary load to a complex generator. In this paper, the method has been applied to the design of interstage matching networks for microwave active circuits. The RFT provides several advantages over most of the usual techniques. It requires neither any transistor model because it directly includes measuring scattering- and noise-parameter data, nor a predetermined matching-circuit topology is necessary. A low-noise amplifier (LNA) design proceeding directly from experimental data is presented. Moreover, a new idea for treating the broadband matching problem leads to the use of an equalizer topology containing cascaded transmission lines with lossy junctions. Thus, gain-flatness and stability are satisfied by designing the input and the output matching circuits by the line-segment technique. An example is presented for the matching of a 0.1-5 GHz amplifier.