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7. PM Axial Flux Machine Design for Hybrid Traction Conception d’une machine à flux axial à aimants permanents pour la traction hybride

Author

de la Barrière O., Hlioui S., Ben Ahmed H., Gabsi M., and LoBue M.

Subjects
Chemical technology, TP1-1185, Energy industries. Energy policy. Fuel trade, HD9502-9502.5
Abstract

the best ways in order to reduce fuel consumption for vehicles. It consists of associating an electric motor next to the classical thermal machine. In this embedded system, the efficiency and the torque per unit mass are very important. So it seems to be a good idea to use a permanent magnet synchronous machine, which is recognized for satisfying these two objectives. Since the allocated volume is rather flat, axial flux topologies are interesting. This paper’s goal is to propose an optimal first design method for such structures, given the allocated volume and the machine requirements. La traction hybride semble actuellement un des moyens les plus prometteurs pour réduire la consommation de carburant des véhicules. Ce procédé consiste à associer un moteur électrique au moteur thermique traditionnel. Pour une telle application embarquée, le rendement, ainsi que le couple massique, sont des critères de conception de première importance. Dans ce contexte, le recours à une machine synchrone à aimants permanents, reconnue pour satisfaire ces deux critères, semble être approprié. Vu que le volume alloué à la machine électrique est de forme discoïde, les topologies à flux axial semblent les plus intéressantes. L’objectif de cet article est de proposer une méthodologie de pré-dimensionnement de tels actionneurs, en ayant fixé au préalable le volume maximal permis ainsi que le cahier des charges de la machine.

Published
2009
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34. Acute myocardial infarction associated with cannabis use

Author

Allouche, E., primary, Chabtri, B., additional, Ouechtati Ben Attia, W., additional, Yahiyaoui, A., additional, Ben Salem, A., additional, Ezzaouia, K.H., additional, Habboubi, S., additional, Chaker, M., additional, Ben Ahmed, H., additional, and Bezdah, L., additional

Published
2020
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38. Analysis of the dynamic behavior of a magnetic gear within a high power wind turbine chain

Author

Desvaux, Melaine, Sire, S, Multon, B., Ben Ahmed, H., Ekeom, D., Systèmes et Applications des Technologies de l'Information et de l'Energie (SATIE), École normale supérieure - Rennes (ENS Rennes)-Université Paris-Sud - Paris 11 (UP11)-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Cachan (ENS Cachan)-Université Gustave Eiffel (UNIV GUSTAVE EIFFEL), Institut de Recherche Dupuy de Lôme (IRDL), Centre National de la Recherche Scientifique (CNRS)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Brest (UBO)-Université de Bretagne Sud (UBS), Jeumont Electric, Altawest, Altawest, Desvaux, Melaine, École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École normale supérieure - Rennes (ENS Rennes)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Centre National de la Recherche Scientifique (CNRS), and Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Centre National de la Recherche Scientifique (CNRS)

Subjects
perturbations, éolienne, décrochage, Multiplicateur magnétique, dynamique, [SPI.NRJ]Engineering Sciences [physics]/Electric power, [SPI.MECA.VIBR]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Vibrations [physics.class-ph], [SPI.MECA.VIBR] Engineering Sciences [physics]/Mechanics [physics.med-ph]/Vibrations [physics.class-ph], [SPI.NRJ] Engineering Sciences [physics]/Electric power
Abstract

Magnetic gear are an alternative that deserves to be studied for its high reliability potential (no friction or lubrication). We are dealing here with the dynamic behavior of a magnetic gear used in a high power (multi-MW) wind application. The study is based on a dynamic non-linear mechatronic model including the components of a wind conversion chain comprising a magnetic multiplier. The rotating resonances of the rotating parts, linked to the magnetic coupling and its low stiffness, are analyzed finely in order to best size the conversion chain and in particular to avoid the risks of stalling. A dynamic pre-sizing procedure is proposed in order to optimize the relationship between the nominal torque of the turbine and the maximum torque transmissible by the magnetic multiplier. This minimizes the oversizing and associated overhead of the multiplier which requires high performance permanent magnets. Simulations taking into account the fluctuations in the aerodynamic torque of the wind turbine illustrate in particular the importance of dynamic dimensioning of magnetic gear., Les multiplicateurs magnétiques constituent une alternative qui mérite d'être étudiée pour son potentiel de haute fiabilité (pas de frottements, ni lubrification). Nous traitons ici du comportement dynamique d'un engrenage magnétique utilisé dans une application éolienne de forte puissance (multi-MW). L'étude est basée sur un modèle dynamique mécatronique non linéaire incluant les composants d'une chaîne de conversion éolienne comprenant un multiplicateur magnétique. Les résonances en rotation des parties tournantes, liées au couplage magnétique et à sa faible raideur, sont analysées finement afin de dimensionner au mieux la chaîne de conversion et notamment d'éviter les risques de décrochage. Une procédure de pré-dimensionnement dynamique est proposée afin d'optimiser le rapport entre le couple nominal de la turbine et le couple maximal transmissible par le multiplicateur magnétique. Cela permet de minimiser le surdimensionnement et le surcoût associé du multiplicateur qui nécessite des aimants permanents à haute performance. Des simulations prenant en compte les fluctuations du couple aérodynamique de la turbine éolienne illustrent en particulier l'importance d'un dimensionnement dynamique des multiplicateurs magnétiques.

Published
2019

39. Differential response to water deficit stress and shade of two wheat (Triticum durum desf.) cultivars : growth, water relations, osmolyte accumulation and photosynthetic pigments

Author

Gharbi, F., Guizani, A., Zribi, L., Ben Ahmed, H., and Mouillot, Florent

Subjects
RWC, Drought, Shading, Osmotic adjustment, fungi, Wheat cultivar, food and beverages
Abstract

This study was conducted to investigate the effects of water deficit stress and shading on two wheat cultivars (Triticum durum Desf. cv Om Rabiaa and cv Maali). Comparison was based on growth, leaf water relations, photosynthetic pigments and the accumulation of organic solute. In both cultivars, water stress deficit significantly decreased total dry mass (TDM), leaf area (LA), water potential (Psi w), osmotic potential (Psi pi) and relative water content (RWC). Photosynthetic pigments, i.e. chlorophyll a (Chl a), chlorophyll b (Chl b) and total chlorophyll (Tot Chl), decreased while carotenoids (car) increased. Proline concentration increased significantly in water stressed plants under full light conditions while sugar accumulated more under shade conditions. In addition, shade improved leaf area, leaf water potential, and osmotic potential as well as alleviated the negative drought impact on photosynthesis performance. For the Maali cultivar, the reduction in RWC and its inability to achieve osmotic adjustment (OA) emphasize this cultivar's sensitivity to water deficit stress. For the Om Rabiaa cultivar, the ability to avoid relative tissue dehydration and preserve a higher RWC with a significant increase in OA in shade-treated plants were tolerance mechanisms enabling this cultivar to absorb water effectively and sustain normal growth and productivity under water stress conditions.

Published
2019

40. The plant-growth-promoting actinobacteria of the genus Nocardia induces root nodule formation in Casuarina glauca

Author

Ghodhbane-Gtari, F., Nouioui, I., Hezbri, K., Lundstedt, E., D'Angelo, T., McNutt, Z., Laplaze, Laurent, Gherbi, Hassen, Vaissayre, Virginie, Svistoonoff, Sergio, ben Ahmed, H., Boudabous, A., and Tisa, L. S.

Subjects
Plant-growth-promotion, Non-Frankia actinobacteria, food and beverages, Auxins, Plant infectivity, Actinorhizal symbiosis, Nocardia
Abstract

Actinorhizal plants form a symbiotic association with the nitrogen-fixing actinobacteria Frankia. These plants have important economic and ecological benefits including land reclamation, soil stabilization, and reforestation. Recently, many non-Frankia actinobacteria have been isolated from actinorhizal root nodules suggesting that they might contribute to nodulation. Two Nocardia strains, BMG51109 and BMG111209, were isolated from Casuarina glauca nodules, and they induced root nodule-like structures in original host plant promoting seedling growth. The formed root nodule-like structures lacked a nodular root at the apex, were not capable of reducing nitrogen and had their cortical cells occupied with rod-shaped Nocardiae cells. Both Nocardia strains induced root hair deformation on the host plant. BMG111209 strain induced the expression of the ProCgNin:Gus gene, a plant gene involved in the early steps of the infection process and nodulation development. Nocardia strain BMG51109 produced three types of auxins (Indole-3-acetic acid [IAA], Indole-3-Byturic Acid [IBA] and Phenyl Acetic Acid [PAA]), while Nocardia BMG111209 only produced IAA. Analysis of the Nocardia genomes identified several important predicted biosynthetic gene clusters for plant phytohormones, secondary metabolites, and novel natural products. Co-infection studies showed that Nocardia strain BMG51109 plays a role as a helper bacteria promoting an earlier onset of nodulation. This study raises many questions on the ecological significance and functionality of Nocardia bacteria in actinorhizal symbioses.

Published
2019

44. DESIGN OF A NOVEL CONCEPT OF SYNCHRONOUS MOTOR FOR TORQUE RIPPLE IMPROVEMENT

Author

Asfirane, Salim, Hlioui, Sami, Ben Ahmed, H., Vido, Lionel, Gabsi, Mohamed, Systèmes et Applications des Technologies de l'Information et de l'Energie (SATIE), École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École normale supérieure - Rennes (ENS Rennes)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Centre National de la Recherche Scientifique (CNRS), Conservatoire National des Arts et Métiers [CNAM] (CNAM), Systèmes d'Energie pour les Transports et l'Environnement (SATIE SETE), Composants et Systèmes pour l'Energie Electrique (CSEE), Université Paris-Seine-Université Paris-Seine-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École normale supérieure - Rennes (ENS Rennes)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Centre National de la Recherche Scientifique (CNRS)-Systèmes et Applications des Technologies de l'Information et de l'Energie (SATIE), École normale supérieure - Rennes (ENS Rennes), Université de Cergy Pontoise (UCP), Université Paris-Seine, École normale supérieure - Cachan (ENS Cachan), and ASFIRANE, Salim

Subjects
[SPI]Engineering Sciences [physics], [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Permanent magnet, Concentrated winding, [SPI] Engineering Sciences [physics], [SPI.ELEC] Engineering Sciences [physics]/Electromagnetism, Double salient, [SPI.NRJ]Engineering Sciences [physics]/Electric power, magnetic equivalent circuits, multi-stack, Torque ripple diminution, [SPI.NRJ] Engineering Sciences [physics]/Electric power
Abstract

International audience; In this paper, a novel design of synchronous machine is presented, the Multi-Stack Flux Modulating Machine (MSFModM). The MSFModM is made of 2 separate machines combined together into one multi-stack structure. The 2 combined stators share the same concentrated armature winding. A 2-D electromagnetic Finite Element Model (FEM) is built for a 3-phase 6/4 motor (6 stator teeth, 4 rotor teeth) and a Magnetic Equivalent Circuit (MEC) is used to evaluate the 3-D effect of the multi-stack machine and to correct the 2-D FEM flux linkage evaluation. The MSFModM concept is compared to a Biased Flux Permanent Magnet Motor (BFPMM). The two motors are supplied by three-phase sine wave currents and comparisons are carried out in terms of flux linkage, back-EMF and torque as the MSFModM exhibits a lower torque ripple.

Published
2017

45. Influence of the wave dispersion phenomenon on the flicker generated by a wave farm

Author

Blavette, Anne, Kovaltchouk, Thibaut, Rongère, François, Jourdain de Thieulloy, Marilou, Leahy, Paul, Multon, Bernard, Ben Ahmed, H., Blavette, Anne, Systèmes et Applications des Technologies de l'Information et de l'Energie (SATIE), École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-École normale supérieure - Rennes (ENS Rennes)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Conservatoire National des Arts et Métiers [CNAM] (CNAM)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Rennes (ENS Rennes), Centre National de la Recherche Scientifique (CNRS), Laboratoire de mécanique des fluides (LMF), École Centrale de Nantes (ECN)-Centre National de la Recherche Scientifique (CNRS), École Centrale de Nantes (ECN), and University College Cork (UCC)

Subjects
hydrodynamic modelling, time delay-based approach, [SPI.NRJ]Engineering Sciences [physics]/Electric power, Flicker, aggregation effect, [SPI.NRJ] Engineering Sciences [physics]/Electric power
Abstract

International audience; — The inherently fluctuating nature of waves may be reflected to some extent in the power output of wave energy converters (WECs). These fluctuations can induce voltage fluctuations which can potentially generate flicker. Hence, wave farm managers will be required to demonstrate that their farm is compliant with grid codes and similar regulations, in order to be granted grid connection. This is usually performed through grid impact assessment studies by means of numerical power system simulators. However, in many studies, the electrical power output of a wave farm is calculated as the sum of identical power profiles corresponding to a single WEC, each shifted by a random time delay. Hence, this approach does not take into account the wave dispersion phenomenon. A comparative study was performed, and is presented in this paper, for assessing the validity of neglecting the influence of this phenomenon on flicker. This study is expected to contribute in defining the required level of hydrodynamic detail necessary for simulating the output power of a wave farm when it is to be used for flicker analyses.

Published
2017

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