{"id":4715,"date":"2018-02-20T16:14:39","date_gmt":"2018-02-20T15:14:39","guid":{"rendered":"https:\/\/l2ep.univ-lille.fr\/?page_id=4715"},"modified":"2026-04-16T13:46:56","modified_gmt":"2026-04-16T12:46:56","slug":"seminaire","status":"publish","type":"page","link":"https:\/\/l2ep.univ-lille.fr\/en\/groupes-de-recherche\/equipe-omn\/seminaire\/","title":{"rendered":"Seminar in OMN TEAM"},"content":{"rendered":"

The research team OMN<\/span><\/a><\/span> specializes in various numerical methods associated with electromagnetic field computation. We regularly organize the Junior Seminar, where presentations are given by our Ph.D. students and postdocs, and we occasionally host an Invited Seminar featuring presentations by external researchers.<\/p>\n

If you are interested in giving a talk or exploring collaboration ideas related to our work, please contact Zuqi<\/span><\/a><\/span> who is in charge of the seminar. The seminar can be conducted in English or French according to your preference, and there is no time limit for its duration.<\/p>\n

Upcoming seminars:\u00a0<\/h1>\n
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2026–2027<\/span><\/strong><\/h3>\n<\/div>\n
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May 05, Junior Seminar<\/h3>\n
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Esteban HUSSON\u00a0<\/span><\/strong><\/h3>\n<\/div>\n
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Mod\u00e9lisation et exp\u00e9rimentation sur un capteur de courant, bas\u00e9 sur la technologie Rogowski<\/span><\/b><\/h2>\n<\/div>\n

Cette th\u00e8se porte sur la mod\u00e9lisation du capteur de courant interne aux disjoncteurs en t\u00eate d\u2019installation (air circuit breaker ou ACB). Ce capteur mesure les courants d’entr\u00e9e de l’installation \u00e0 prot\u00e9ger, gr\u00e2ce \u00e0 un tore Rogowski, mais sert \u00e9galement \u00e0 l\u2019auto-alimentation de l\u2019ACB gr\u00e2ce \u00e0 des transformateurs de courant. La mesure de courant permet d\u2019assurer les fonctions de protection et de monitoring. La fonction d\u2019auto-alimentation est exig\u00e9e \u00e0 l\u2019ACB pour pouvoir fonctionner quel que soit le type de d\u00e9faut sur l\u2019installation \u00e9lectrique. Le probl\u00e8me principal se situe donc dans les interactions entre le tore de Rogowski et le circuit magn\u00e9tique du TC. Il est dimensionnellement impossible dans l\u2019ACB de s\u00e9parer physiquement ces deux \u00e9l\u00e9ments. Le transformateur de courant et le tore de Rogowski doivent donc coexister dans un environnement proche, et cela impacte fortement les performances de mesure demand\u00e9es au tore de Rogowski.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

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Timon CALLENS<\/span><\/strong><\/h3>\n
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Super-Resolution for Magnetic Field Estimation in Rotor-Eccentric Induction Motors<\/span><\/b><\/h2>\n<\/div>\n

The squirrel cage induction motor forms the backbone of modern industrial drive systems. Within its applications, mechanical faults emerge as the leading cause of failure, with approximately 80% attributed to radial rotor eccentricity. This misalignment between the geometric centers of the stator and rotor creates a non-uniform air gap that distorts the magnetic field and generates an unbalanced magnetic pull (UMP), which can irreversibly accelerate mechanical damage. The high computational cost associated with traditional simulation methods limits their use to diagnostic and design purposes. Overcoming the computational limitations of these solvers is a necessary prerequisite for implementing real-time analysis and UMP mitigation in motor control.<\/p>\n

To address this, my recent work proposes a physics-informed super-resolution framework that reconstructs internal magnetic fields using only measurable inputs: stator voltages and currents, rotor angular speed, and rotor mechanical angle. Using a neural network, these accessible measurement variables are upscaled to the scalar magnetic potentials of a non-linear magnetic equivalent circuit, and the instantaneous rotor eccentricity is estimated, bypassing the iterative solving process. An analytical physics stage subsequently computes the electromagnetic torque and radial forces using virtual work. The framework achieves high reconstruction accuracy across both transient and steady-state regimes at the sub-millisecond scale.<\/p>\n

The presentation will cover the core methodology and results of this framework, and will conclude with an overview of my current research. As part of my joint PhD in collaboration with the University of Lille, the next objective is to apply a similar super-resolution methodology to 3D finite element simulations using code_carmel.<\/p>\n

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June 01, Junior Seminar<\/h3>\n
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Vyvien DUMONT\/Fatima HASSAN<\/span><\/strong><\/h3>\n<\/div>\n<\/div>\n<\/div>\n
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July 03, Junior Seminar<\/h3>\n
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Chlo\u00e9 PETRYKOWSKI<\/span><\/strong><\/h3>\n<\/div>\n<\/div>\n<\/div>\n
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Past seminars:<\/h1>\n<\/div>\n

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Mars 31, Junior Seminar<\/h3>\n
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L\u00e9a SALEH<\/span><\/strong><\/h3>\n<\/div>\n
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Experimental & Analytical Macroscopic Study of the Magnetic Aging of Non-Oriented Iron Silicon Electrical Steels\u00a0<\/span><\/b><\/h2>\n<\/div>\n

Throughout their lifecycle, non-oriented electrical steels (NO ES) are subjected to thermal and mechanical constraints due to both manufacturing processes and operating conditions. Exposure to high operating temperatures over time leads to the so-called magnetic aging phenomenon, defined as the irreversible degradation of the ES magnetic performance due to the precipitation of carbides that act by pinning domain wall movement during magnetization, leading to an increase in iron losses. Additionally, mechanical constraints affect magnetic behavior, including reversible elastic stresses and irreversible plastic strain. Elastic stresses induce reversible domain wall reorientation to minimize magnetoelastic energy, while plastic deformation introduces dislocations that further increase iron losses. Although the individual effects of elastic and plastic constraints have been extensively studied in the literature, their coupling with magnetic aging remains largely unexplored.<\/p>\n

This PhD work aims first to establish a comprehensive understanding of magnetic aging mechanisms, as a foundation for investigating their coupling with elastic and plastic mechanical constraint effects. Experimentally, individual thermal aging studies, as well as studies combined with elastic stress and plastic mechanical loading, have been conducted, revealing a clear interaction between thermal and mechanical effects. Building on these results, predictive models based on iron loss separation and the first magnetization B\u2013H curve have been developed to describe the evolution of magnetic properties with aging time and temperature. In addition, a first approach to a multi-scale model linking the macroscopic coercive field to microscopic precipitate size and volume fraction is proposed.<\/p>\n<\/div>\n<\/div>\n

Sanchez GAETAN<\/span><\/strong><\/h3>\n
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Using MEMS SAW sensors for motor faults diagnosis and multiphysic characterization of steel sheets\u00a0<\/span><\/b><\/h2>\n<\/div>\n

The diagnosis of high power electrical machines advanced techniques to monitor performance and predict failures, thereby reducing maintenance downtime. To achieve this, maintenance engineers and technicians need knowledge of machine condition, through measurements of physical parameters like vibrations, temperature, or magnetic field. The development of suitable sensors for effective real-time monitoring is essential for instrumenting electrical machines. While current techniques rely on conventional sensors (Hall effect, thermocouples, strain gauges), these face critical limitations: power supply requirements, wired connections, and poor resilience to industrial conditions\u2014restricting their integration inside motors where essential health data is located. SAW sensors offer a viable alternative due to their compact size and their lack of need for power supply. Building on Dr. Marbouh’s thesis work, a collaborative effort between IEMN, L2EP, and Jeumont Electric successfully fabricated magneto-thermo-elastic SAW sensors.<\/p>\n

The goal of my PhD is to adapt these SAW sensors in a single RF multiphysical chip and integrate these chips in industrial motors for fault detection. A digital twin should be established to determine the number and location of SAW sensors inside the motor to best describe its health. The focus of this presentation will be on the fabrication and integration of SAW magnetic sensors for two applications\u00a0: the characterization of magnetic losses in steel sheets and the measurement of stray magnetic fluxes of asynchronous motors.<\/p>\n

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Mars 12, Junior Seminar<\/span><\/h3>\n

Badr CHERQUAOUI<\/span><\/strong><\/span><\/strong><\/h3>\n

D\u00e9veloppement de m\u00e9thodes adapt\u00e9es \u00e0 la mod\u00e9lisation de d\u00e9fauts complexes en Evaluation Non-Destructive par courants de Foucault<\/span><\/b><\/span><\/b><\/h2>\n<\/div>\n

L\u2019inspection des tubes de g\u00e9n\u00e9rateurs de vapeur repose largement sur le Contr\u00f4le Non Destructif par Courants de Foucault (CND\u2011CF). Cette technique consiste \u00e0 induire des courants de Foucault au sein des tubes, puis \u00e0 mesurer les perturbations qu\u2019ils subissent lorsqu\u2019ils interagissent avec une fissure. Les signaux obtenus sont riches en information ; cependant, leur interpr\u00e9tation reste d\u00e9licate. En effet, \u00e0 partir d\u2019une mesure seule, il est souvent difficile d\u2019\u00e9tablir un lien direct entre le signal et les caract\u00e9ristiques g\u00e9om\u00e9triques de la fissure.<\/p>\n

Afin de mieux appr\u00e9hender ce probl\u00e8me, nous avons d\u00e9velopp\u00e9 et valid\u00e9 un mod\u00e8le de simulation num\u00e9rique permettant de reproduire virtuellement le proc\u00e9d\u00e9 CND\u2011CF, y compris pour des d\u00e9fauts g\u00e9om\u00e9triquement complexes. Ce mod\u00e8le nous a permis de g\u00e9n\u00e9rer une base de donn\u00e9es de signaux associ\u00e9e \u00e0 diff\u00e9rents param\u00e8tres de fissure. \u00c0 partir de cette base, nous avons adopt\u00e9 un cadre bay\u00e9sien visant \u00e0 explorer l\u2019espace des param\u00e8tres de fissure en privil\u00e9giant les zones o\u00f9 la densit\u00e9 de probabilit\u00e9 est la plus \u00e9lev\u00e9e. Pour cela, nous utilisons des cha\u00eenes de Markov. L\u2019objectif n\u2019est pas de d\u00e9terminer un unique jeu de param\u00e8tres, mais d\u2019estimer une densit\u00e9 de probabilit\u00e9 pour chaque param\u00e8tre caract\u00e9risant la fissure.\u00a0<\/p>\n<\/div>\n

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Tarek DERRADJI<\/span><\/strong><\/h3>\n

Error estimation for quantities of interest in electromagnetic field computation for eddy current non-destructive testing applications<\/span><\/b><\/h2>\n<\/div>\n

Non-destructive testing (NDT) using eddy currents is widely employed for the inspection of steam generator tubes in nuclear power plants. However, establishing a direct link between sensor output signals and defect characteristics remains challenging. Numerical simulations, such as the finite element method, therefore constitute a valuable tool for building databases that relate defect features to sensor signatures. Nevertheless, numerical errors, largely dominated by mesh quality, may be of the same order of magnitude as the defect signature itself, which complicates the reliable construction of such databases.<\/span><\/p>\n

To address this issue, a posteriori error estimation techniques specifically targeting quantities of interest (e.g., magnetic flux in a given region), rather than classical global energy-based measures, have been developed. These approaches require the construction of admissible solutions to compute guaranteed error bounds. However, constructing admissible solutions through dual formulations typically requires solving an additional global problem, which leads to significant computational costs and limits their applicability in industrial contexts.<\/span><\/p>\n

The objective of this Ph.D. thesis is to achieve a practical trade-off between accuracy and computational cost in the construction of admissible solutions, in particular through local reconstruction techniques.<\/span>
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In this presentation, the first results of this work are presented for the 3D magnetostatic problem using the \u03a9-formulation. An alternative strategy based on equilibrated flux reconstruction is investigated, where admissible solutions are obtained by solving small independent problems on vertex patches of the mesh instead of an additional global system. This local approach incorporates a modified formulation to handle discontinuities in magnetic permeability at material interfaces. Preliminary results show that the local reconstruction strategy provides error estimates comparable to those obtained with the global approach while offering the capability to reduce computational cost.<\/span><\/p>\n

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February 13, Junior Seminar<\/h3>\n

Majid KHALILI DERMANI\u00a0<\/span><\/strong><\/h3>\n

Bond graph modeling of radiated electromagnetic couplings<\/span><\/b><\/h2>\n
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Improving the energy efficiency of complex multiphysics systems requires consistent modeling across multiple spatial and temporal scales, from full energy conversion chains to individual components. Energy-based approaches have proven to be particularly effective in providing a unified framework for modeling, simulation, and control across these scales. However, maintaining coherence between detailed physical descriptions and system-level representations remains a major challenge.<\/p>\n

Electromagnetic coupling plays a central role in this difficulty, as electromagnetic fields inherently propagate across space and interact with multiple subsystems simultaneously.\u00a0 Conventional modeling approaches typically rely either on simplified system-level representations or on detailed electromagnetic simulations that remain weakly connected to global energetic behavior. This separation limits the coherence and predictability of electromagnetic analysis, especially in systems where field interactions play a significant role.<\/p>\n

This work proposes a unified modeling framework for electromagnetic couplings based on a systemic and energy-consistent approach. The methodology establishes a coherent link between field-based formulations of Maxwell\u2019s equations and macroscopic energetic representations using the bond graph formalism. By embedding spatially discretized electromagnetic field models into an energetic system framework, local phenomena such as coupling effects, losses, and saturation can be analyzed consistently with system-level energy flows.<\/p>\n

The proposed approach is supported by detailed numerical formulations and validated through one-, two-, and three-dimensional case studies, including comparisons with commercial electromagnetic simulation tools. The results demonstrate the ability of the framework to capture multiscale electromagnetic effects while preserving energetic consistency.<\/p>\n

This work contributes to more coherent modeling and analysis of electromagnetic interactions in electrical devices and provides a foundation for future design, optimization, and educational applications in complex multiphysics systems.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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January 13, Junior Seminar<\/h3>\n
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Ilyas BENNIA<\/span><\/strong><\/h3>\n

Internal and External Magnetic Sensors for Electrical Machine Diagnostics: Experimental Development and FEM-Based Analysis<\/h2>\n
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Electrical machines are everywhere, from industrial drives to household appliances. Like all complex systems, they can develop hidden faults that reduce performance or cause failures. Detecting these issues early is crucial, and magnetic sensing offers a unique window into the inner workings of a machine, revealing internal faults and subtle electromagnetic changes.<\/span><\/p>\n<\/div>\n

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By combining detailed finite element simulations with experimental measurements, A framework is created that bridges numerical models and real-world observations. The simulations capture how flux variations ripple inside the motor and radiate into the surrounding magnetic field, while experiments provide tangible evidence of these phenomena under the same operating conditions. Careful analysis in the frequency domain highlights the characteristic spectral fingerprints of faults, allowing a meaningful comparison between what the sensors capture internally and externally.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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2025<\/a>

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December 04, 2025, Junior Seminar<\/h3>\n
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Ronan CORIN<\/span><\/strong><\/h3>\n

Topology optimization and additive manufacturing of magnetic cores<\/span><\/h2>\n
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The technological evolutions in topics like new materials or manufacturing processes allow us to consider new solutions to design conversion systems in electrical engineering. One of these evolutions is the potential use of additive manufacturing, especially with a low-cost and easy to use process called Fused Deposition Modelling. But there are several questions to answer. There are very few studies about the use of additive manufacturing in electrical engineering, and the majority of them deal with another expensive and difficult to use process called Selective Laser Melting. Also, typical metallic materials used in low frequency applications like silicon-iron or copper are rarely used in additive manufacturing. Lastly, the magnetic cores obtained by additive manufacturing are not laminated but bulk. It leads to a higher level of eddy current losses, and they must be lowered by increasing the silicon content and optimizing cross section shape.
The work already completed to overcome these challenges include a first part dedicated to understanding the manufacturing process, especially the filament fabrication, its characterization and the definition of the appropriate thermal cycle to debind and sinter the printed shapes. A second part is dedicated to the optimization of the entire magnetic core or its cross section, which lead us to the printing and the characterization of the optimized parts.<\/span><\/div>\n
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Juin 17, 2025, Junior Seminar<\/h3>\n
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Liwaa ABOUCHAKRA<\/span><\/strong><\/h3>\n

Reduced-Order Model Exploitation for the Multiparametric Analysis of the Magneto-Vibro-Acoustic Behavior of Electric Machines<\/span><\/h2>\n
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This work addresses the challenge of optimizing computational efficiency in the analysis of magneto-vibro-acoustic behavior in electric machines, particularly under the influence of parametric variations stemming from manufacturing imperfections. High-fidelity Finite Element Method simulations, while accurate, become computationally expensive when multiple configurations must be evaluated. Additionally, achieving sufficient accuracy in electromagnetic quantities is a prerequisite for reliable vibroacoustic analysis. To overcome these challenges, advanced Reduced-Order Modeling techniques are proposed, combining an enhanced Greedy Proper Orthogonal Decomposition with Double Component Mode Synthesis. These methods significantly reduce computational time while preserving a high level of accuracy in capturing the system\u2019s vibroacoustic response. The proposed framework enables efficient and robust analysis across a broad spectrum of manufacturing-induced variations\u2014such as geometric eccentricities, supply harmonics, and mechanical tolerances\u2014thereby providing a powerful tool for early-stage design evaluation and optimization.<\/span><\/div>\n
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Lionel GOUNOU<\/span><\/strong><\/h3>\n

Alternateurs hydro-electriques flexibles : possibilites et limitations <\/span><\/h2>\n
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La province du Qu\u00e9bec, au Canada, produit pr\u00e8s de 99 % de son \u00e9lectricit\u00e9 \u00e0 partir de sources renouvelables, dont environ 94 % proviennent de l\u2019\u00e9nergie hydro\u00e9lectrique comme mentionn\u00e9 dans le site de R\u00e9gie d’\u00e9nergie du Canada. En tant que l\u2019un des plus grands producteurs mondiaux d\u2019hydro\u00e9lectricit\u00e9, Hydro-Qu\u00e9bec exploite environ 340 groupes turbines-alternateurs r\u00e9partis dans 61 centrales, pour une capacit\u00e9 install\u00e9e totale d\u2019environ 37,2 GW ces donn\u00e9es ont \u00e9t\u00e9 chiffr\u00e9es dans le site de Hydro Qu\u00e9bec Production. Dans le contexte de la transition \u00e9nerg\u00e9tique actuelle et de l\u2019int\u00e9gration croissante de sources renouvelables intermittentes comme l\u2019\u00e9olien et le solaire, de nouveaux d\u00e9fis op\u00e9rationnels \u00e9mergent. L\u2019un des principaux probl\u00e8mes r\u00e9side dans la variabilit\u00e9 de ces sources, qui complique la planification et la gestion de la production d\u2019\u00e9lectricit\u00e9.<\/span>\n

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Les unit\u00e9s de production conventionnelles fonctionnent g\u00e9n\u00e9ralement \u00e0 puissance fixe, ce qui limite la possibilit\u00e9 de valoriser l\u2019\u00e9nergie renouvelable disponible en cas de surplus. Bien que le stockage d\u2019\u00e9nergie \u00e0 grande \u00e9chelle soit encore difficile \u00e0 mettre en \u0153uvre de mani\u00e8re industrielle, une alternative prometteuse consiste \u00e0 faire fonctionner les alternateurs hydro\u00e9lectriques existants de fa\u00e7on plus flexible, \u00e0 des puissances active et r\u00e9active variables, au-del\u00e0 de leurs r\u00e9gimes nominaux. Cependant, un tel fonctionnement ne doit pas compromettre l\u2019int\u00e9grit\u00e9 ni la dur\u00e9e de vie des machines.<\/span><\/p>\n

Ce projet de doctorat vise \u00e0 \u00e9valuer la faisabilit\u00e9 du fonctionnement flexible des alternateurs hydro\u00e9lectriques tout en garantissant leur fiabilit\u00e9 et leurs performances. Pour cela, un mod\u00e8le num\u00e9rique d\u00e9taill\u00e9 par \u00e9l\u00e9ments finis d\u2019un alternateur connect\u00e9 au r\u00e9seau sera d\u00e9velopp\u00e9, puis valid\u00e9 par comparaison avec des mesures r\u00e9elles \u00e0 diff\u00e9rents points de fonctionnement. Ce mod\u00e8le permettra de simuler les conditions hors-nominales, de quantifier et de localiser les pertes fer au sein de la machine, et ainsi d\u2019identifier les zones critiques susceptibles de surchauffer (points chauds). Ces zones seront ensuite v\u00e9rifi\u00e9es sur d\u2019autres machines op\u00e9rant dans des conditions similaires. L\u2019objectif final est de proposer une m\u00e9thodologie de surveillance robuste permettant une exploitation flexible et s\u00e9curis\u00e9e des alternateurs, en phase avec l\u2019essor des \u00e9nergies renouvelables.<\/span><\/p>\n

Ce travail aura des retomb\u00e9es importantes sur les plans scientifique et technologique. Il contribuera \u00e0 l\u2019\u00e9laboration de strat\u00e9gies avanc\u00e9es de surveillance pour les machines synchrones en fonctionnement flexible, \u00e0 l\u2019optimisation de la production d\u2019\u00e9lectricit\u00e9 renouvelable, et au renforcement du leadership du Qu\u00e9bec en mati\u00e8re d\u2019innovation dans les \u00e9nergies propres.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

May 14, 2025, Junior Seminar<\/h3>\n

Ayoub AINOUZ<\/span><\/strong><\/h3>\n

Development of an approach combining physical modeling and artificial intelligence for modeling the magnetic properties of electrical steels<\/span><\/h2>\n
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In the context of modern electric motor systems, accurately and efficiently modeling the magnetic properties of electrical steels is crucial for improving energy performance and reducing losses. These materials operate under mechanical and thermal stresses that can significantly alter their magnetic behavior. Such conditions lead to complex magneto-mechanical and magneto-thermal effects that traditional models struggle to capture.
While physical models like Jiles-Atherton provide good interpretability, they face limitations in terms of accuracy, computational cost, and adaptability to dynamic or multi-physical conditions. To address these challenges, we propose a hybrid approach that combines the Jiles-Atherton model with a feedforward neural network. The neural network is designed to learn and correct the residual errors of the physical model, especially in dynamic regimes or under mechanical stress, thus enhancing both accuracy and robustness.
This combination allows us to preserve the physical meaning of the model while improving generalization beyond the training range. It also ensures faster computation, which is essential for integration into design tools.<\/div>\n
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Ali SALLOUKH<\/span><\/strong><\/h3>\n

Multiphysics modeling of an {inverter + machine + gearbox} system for an aeronautical application<\/span><\/h2>\n
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The search for high-power-density electric aircraft propulsion requires a holistic, top-down approach.<\/span><\/div>\n
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The size and weight of the electric motor depend mainly on the torque, and a further improvement in power density can be achieved by choosing a higher number of poles. However, this will lead to an increase in speed, voltage and electric frequency. Moreover, fault tolerance is ensured by several three-phase inverters, which have the additional advantage of sharing the total motor power. <\/span><\/div>\n
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The subject of this thesis concerns the multiphysics modeling and dimensioning of a permanent magnet synchronous machine (PMSM) for an aeronautical application, taking into account the system {inverter + machine + gearbox}. The aim of this project is to study the interaction between system components: the trade-offs between the number of motor poles (switching frequency), motor speed, number of inverters, system voltage and reduction ratio. The overall impact on system weight can only be achieved by optimizing the design of the motor, drive and gearbox.<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

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April 23, 2025, Junior Seminar<\/h3>\n

Mohamed Reda SAOUTHI<\/span><\/strong><\/h3>\n

M\u00e9thodologie de dimensionnement et de supervision \u00e9nerg\u00e9tique d\u2019un smart grid ferroviaire<\/span><\/h2>\n
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The integration of decentralized photovoltaic generation and energy storage systems into railway electrification networks appears to be a key solution, both for contributing to the energy transition and for improving technical and economic performance in response to ever-increasing energy demand.<\/span>
The objective of this thesis is to propose a methodology for the optimal sizing and energy management of the complete system, applied to two different architectures for connecting the photovoltaic installation and the storage system. In the first architecture, the systems are connected to the substation with a purely economic objective. In the second architecture, the systems are connected at the paralleling point between two substations, aiming for both economic and technical objectives\u2014particularly the maintenance of voltage levels at the pantograph.<\/span>
Two distinct methodologies are proposed. The first involves the development of a linear optimization model that simultaneously optimizes the sizing of system components and energy management, ensuring results are obtained within a reduced computation time. The second methodology is based on a two-level approach, relying on more detailed optimization models that integrate the nonlinearities naturally present in the optimization objectives, functional constraints, and the behavioral laws of system components.<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

Philom\u00e8ne CARTON<\/span><\/strong><\/h3>\n

Development of methods adapted to the electromagnetic modeling of general ground networks<\/span><\/h2>\n
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Grouding network modeling using the method of moments is possible with known parameters and tools such as CDEGS\u00ae. However, in practice, information such as soil characteristics and grid positions are often uncertain, leading to discrepancies between simulation and reality. For more accurate modeling, a stochastic approach is required, where uncertain parameters are represented by random variables. Although material uncertainties do not pose a problem in a linear framework, geometric uncertainties (element dimensions, position, physical characteristics) have been partially addressed. The major problem lies in the realistic modeling of grounding grids (MALT), which remains a challenge to be overcome. One proposed solution is to create a parametric model of grid generation, taking into account tube aging and corrosion. This model will be coupled with an electromagnetic ground model for the ground network. The complexity of the problem will require the use of advanced numerical methods and the selection of the most influential parameters to avoid excessive computation times. Finally, different methods of uncertainty propagation will be explored to determine the most appropriate.<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n

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March 11, 2025, Junior Seminar<\/h3>\n

Sqalli GHALI<\/span><\/strong><\/h3>\n

From Material to Magnetic Structure through Additive Manufacturing<\/span><\/h2>\n
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Additive manufacturing has been gaining increasing interest in recent years, offering innovative solutions across various fields, including electrical engineering. Among the available processes, Fused Deposition Modelling (FDM) processes stand out for their accessibility, both in terms of cost and implementation complexity. We chose to develop a FDM-based process (PIM-like) to enable the production of intricate and customized magnetic parts while remaining affordable and widely applicable.<\/div>\n
This work has focused on acquiring a comprehensive understanding of the entire manufacturing chain of soft magnetic parts (MnZn and NiZn ferrites) using this process, from filament formulation to the characterization of the sintered part. In parallel, we investigated the potential of our FDM-based process for material structuring, by exploring how specific process parameters\u2014such as the deposition direction\u2014can influence the final properties of the printed components.<\/div>\n<\/div>\n<\/div>\n
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Ze GUO<\/span><\/strong><\/h3>\n

Hybrid Surrogate Modeling based on Physics and Data Driven Techniques applied to Multi-parameter Electromagnetic Problems<\/h2>\n
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Electric equipment is crucial for power generation, transmission, and conversion. Ensuring its reliable operation has become essential, leading to increased focus on online monitoring, fault prediction, and performance forecasting throughout its life cycle. The digital twin is a key technology for real-time monitoring and life-cycle management of industrial products. Constructing a digital twin for electric equipment requires extensive data, including information on health and fault conditions. In this context, surrogate modeling plays a critical role by enabling the rapid generation of high-fidelity, multi-parameter simulation data across different operating conditions. The objective of this PhD research is to develop surrogate models for multi-parameter, nonlinear electromagnetic problems. Inspired by the intrinsic advantages of both physics-based and data-driven approaches, we aim to combine their strengths to construct a hybrid surrogate model.<\/div>\n
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February 04, 2025, Junior Seminar<\/h3>\n

Fabien DANCOISNE\u00a0<\/span><\/strong><\/h3>\n

Characterization and modeling of soft ferromagnetic steels aging for iron losses reduction\u00a0<\/span><\/h2>\n
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\u00ab\u00a0Magnetic aging\u00a0\u00bb refers to the degradation of in-service magnetic properties of Fe-Si steels when submitted to moderate temperature. This phenomenon is due to carbides or nitrides precipitation at low temperatures (less than 200\u00b0C), that corresponds to typical operating temperatures of electrical machines. At the microscopic scale, it was determined that only Fe-Si alloys with silicon content lower than 3 wt.% are prone to magnetic aging. These low-grade Fe-Si steels correspond however to the largest part (73%) of the current market of NOES, i.e. 9.8 million tons produced in 2019 in the world. In the literature, only scarce attempts have been made to model the precipitation kinetics in this system. The aim of the PhD is to develop multi-physical models based on experimental investigations from the microscopic to macroscopic scales of aging mechanisms in electrical steels and the consequences on iron losses.<\/span><\/div>\n<\/div>\n<\/div>\n
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<\/h3>\n

January 07, 2025, Junior Seminar<\/h3>\n

Idriss NACHETE<\/span><\/strong><\/h3>\n

Optimum Design Methodology of Planar Inductor Combining High and Low Permeability Magnetic Materials used for High-Current DC\/DC Converter<\/span><\/h2>\n
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HLP Planar inductors made of combined low permeability and high permeability planar cores allow to achieve better performance, where a significant reduction in copper losses, up to 7 times, is achieved compared to traditional planar inductors with airgap. In this paper, an optimization methodology is proposed to design high performance HLP planar inductors with double-side liquid cooling system. A Simplified 2D Model to compute rapidly the planar inductor\u2019s copper losses, likewise, the thermal management based on the vertical thermal flow from the winding and the core to the cold plates are introduced and used for the design process. Based on magnetic, loss and thermal analytical models, an optimal design process is developed and applied to the case of a planar inductor operated in a 21-kW SiC-based buck converter.<\/span><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n
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\n2024<\/a>
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November 28, 2024, 14:00, Invited Seminar (Esprit Building, Saphir 1)<\/span><\/h3>\n
\"\"<\/a>Pr. Hajime IGARASHI<\/span><\/strong>\u00a0(Hokkaido University, Japan)<\/span><\/strong><\/figure>\n
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Professor Hajime IGARASHI received the Ph.D. degree in engineering from Hokkaido University in 1992. He has been a professor at Graduate School of Information Science and Technology, Hokkaido University, since 2004. He was a guest researcher at Berlin Technical University, Germany, under support from the Humboldt Foundation from 1995\u20131997. His research area is computational electromagnetism, optimal design and AI-based design of electric machines. He has authored and coauthored more than 300 peer-reviewed journal papers. He is the author of the book entitled \u201cTopology Optimization and AI-based Design of Power Electric and Electrical Devices\u201d published from Academic Press in 2024.\u00a0<\/span><\/p>\n<\/div>\n<\/div>\n

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Stochastic Topology Optimization of electromagnetic devices<\/h2>\n
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This presentation begins with an overview of topology optimization based on stochastic and deterministic methods. We then focus on stochastic topology optimization based on Gaussian basis functions, which has been applied to the design of permanent magnet motors, dielectric lens antennas, and wireless power transmission devices. We extend this method to perform hybrid parameter-topology optimization, multi-material optimization, and fast optimization based on deep learning. Finally, we discuss the difficulties in stochastic topology optimization and its prospects.<\/span><\/p>\n<\/div>\n<\/div>\n

<\/h3>\n

December 02, 2024, Junior Seminar<\/h3>\n

Joel DRAPPIER<\/span><\/strong><\/h3>\n

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Numerical Resolution of Nonlinear Electromagnetic Problems in the<\/span><\/span>
Presence of Anisotropy<\/span><\/h2>\n
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Electrical machines are currently the subject of many researches to improve their efficiency by a few percent. One solution consists in using high performance magnetic materials (sheets). However, it appears that the behavior of these materials is highly nonlinear and anisotropic and also presents hysteresis when used in machines. In order to evaluate precisely the efficiency, before the construction of real prototypes, we use numerical modeling that must take into account the nonlinear character of these materials. The L2EP has been developing, with EDF R&D in the context of LAMEL, for many years a computational code, named code_carmel, based on the finite element method to model electromagnetic devices in low frequency. The objective of this PhD is to add to code_carmel the resolution of nonlinear problems integrating anisotropic and hysterical models. In this presentation, we will discuss the procedure developed to integrate anisotropy into the code, as well as a practical simulation case involving a toroidal core and a transformer corner, focusing on the field evolution and the resulting evaluation of iron losses.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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November 07, 2024, Junior Seminar<\/h3>\n

Madeline CHAUVIER (UHPF)<\/span><\/strong><\/h3>\n

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Calcul en 2D de charges d’espace cr\u00e9\u00e9es par les lignes de transport HVDC\u00a0<\/span><\/h2>\n
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Lors de cet expose\u0301, je pre\u0301senterai les proble\u0300mes de charges d\u2019espace lie\u0301s au transport du courant e\u0301lectrique dans les lignes haute tension a\u0300 courant continu (High Voltage Direct Current (HVDC)). Je pre\u0301ciserai le mode\u0300le retenu couplant le potentiel e\u0301lectrique et la densite\u0301 de charge d\u2019espaces. En dimension 2, dans le cas d\u2019une ge\u0301ome\u0301trie simple, je donnerai la forme des solutions. Dans un cadre plus ge\u0301ne\u0301ral, j\u2019ai obtenu un re\u0301sultat d\u2019existence de solutions mais celles-ci ne sont plus calculables. C\u2019est pourquoi je proposerai un algorithme nume\u0301rique et des simulations associe\u0301es. Afin de valider cette me\u0301thode nume\u0301rique, je comparerai, dans le cas simple, la solution exacte et la solution approche\u0301e. Je pre\u0301senterai aussi des re\u0301sultats nume\u0301riques pour une ge\u0301ome\u0301trie plus re\u0301aliste.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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October 11, 2024, Seminar<\/h3>\n

Marwane DEHRBECOURT<\/span><\/strong><\/h3>\n
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FFF additive manufacturing of ferrites: from filament conception to characterization<\/h2>\n
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The democratization of additive manufacturing technologies began in the late 80s, with the appearance of the first 3D printers.\u00a0 Today, they offer solutions adapted to the challenges faced in various domains of scientific research and industry. In particular, electrical engineering can greatly benefit from the opportunities offered by FFF (fused filament fabrication) printing and the diversification of materials used. This process enables the creation of complex, customized structures, and offers the advantage of low manufacturing costs. Our work aims to fully master the PIM-like additive manufacturing chain for the production of MnZn and NiZn ferrites: feedstock development, FFF printing, debinding, sintering and process validation by magnetic characterization.<\/p>\n

This work is part of the joint AMbassador project carried oud with the CEA, which aims to design a gradient-permeability architecture with advanced geometries not achievable by conventional manufacturing processes.<\/div>\n
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September 18 & 19, 2024, Invited Seminar<\/h3>\n
\"\"<\/a>Pr. Alessandro FORMISANO<\/span><\/strong> (Universit\u00e0 della Campania \u201cLuigi Vanvitelli\u201d, Italy)<\/span><\/strong>\n

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Alessandro Formisano holds a MS in Electronic Engineering from Univ. di Napoli \u201cFederico II\u201d and a PhD in Electrical Sciences from the same university. He is full professor of Electrical Sciences since 2016 at Universit\u00e0 della Campania \u201cLuigi Vanvitelli\u201d. <\/span><\/p>\n<\/div>\n

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Professor Formisano interests are in the numerical computation of electromagnetic fields, in the resolution of inverse problems in electromagnetism, in the machine learning approaches, and finally in the engineering aspects of nuclear fusion. <\/span>He was Co-Chairman of the 2020 Edition of the CEFC, and is the general chairman of the Compumag 2025 conference.<\/span><\/p>\n<\/div>\n<\/div>\n<\/figure>\n

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Inverse Source Problems in Low Frequency Electromagnetism: Classical Approaches and the role of Machine Learning Techniques<\/h2>\n

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Inverse Source Problems are characterized by the need of identifying a source from the measurement of its effects. In the case of Low Frequency Electromagnetism, a typical case is the reconstruction of current distribution from remote magnetic field. This problem presents an ill posed nature, and consequently its resolution requires special actions to produce reliable results. In this short seminar, the classical regularization methods will be briefly discussed, in the perspective of providing a gentle introduction to more recent approaches based on machine learning.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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September 23, 2024, Invited Seminar<\/h3>\n

\"\"<\/a>Pr. Alessandro FORMISANO <\/span><\/strong> (Univ. Della Campania \u201cLuigi Vanvitelli\u201d, Italy)<\/span><\/strong><\/p>\n

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Alessandro Formisano holds a MS in Electronic Engineering from Univ. di Napoli \u201cFederico II\u201d and a PhD in Electrical Sciences from the same university. He is full professor of Electrical Sciences since 2016 at Universit\u00e0 della Campania \u201cLuigi Vanvitelli\u201d. <\/span><\/p>\n<\/div>\n

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Professor Formisano interests are in the numerical computation of electromagnetic fields, in the resolution of inverse problems in electromagnetism, in the machine learning approaches, and finally in the engineering aspects of nuclear fusion. <\/span>He was Co-Chairman of the 2020 Edition of the CEFC, and is the general chairman of the Compumag 2025 conference.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n

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A short introduction to (Magnetically Confined) Thermonuclear Fusion<\/span><\/h2>\n

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The world energy demand is getting higher and higher, but the fossil sources are rapidly exhausting, not to speak of their environmental impact. The need for alternative, sustainable energy sources is strong. Among those, nuclear fusion represents one of the top choices, but its complexity is overwhelmingly demanding: high-energy physics to be controlled, incredibly large magnetic fields to be generated with high accuracy and driven accordingly to tightly controlled waveforms. Not to speak of the intrinsically unstable nature of a burning plasma! The technology behind a possible reactor represents one of the most advanced research frontiers in engineering. This short seminar aims to deliver a gentle introduction to the physics of magnetically confined thermonuclear fusion, showing the achievements but also the critical aspects of this promising technology.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n

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July 09, 2024, Junior Seminar<\/h3>\n

Esteban HUSSON<\/span><\/strong><\/p>\n

Mod\u00e9lisation et exp\u00e9rimentation sur un capteur de courant, bas\u00e9 sur la technologie Rogowski<\/b><\/h2>\n<\/div>\n

Cette th\u00e8se porte sur la mod\u00e9lisation du capteur de courant interne aux disjoncteurs en t\u00eate d\u2019installation (air circuit breaker ou ACB). Ce capteur mesure les courants d’entr\u00e9e de l’installation \u00e0 prot\u00e9ger, gr\u00e2ce \u00e0 un tore Rogowski, mais sert \u00e9galement \u00e0 l\u2019auto-alimentation de l\u2019ACB gr\u00e2ce \u00e0 des transformateurs de courant. La mesure de courant permet d\u2019assurer les fonctions de protection et de monitoring. La fonction d\u2019auto-alimentation est exig\u00e9e \u00e0 l\u2019ACB pour pouvoir fonctionner quel que soit le type de d\u00e9faut sur l\u2019installation \u00e9lectrique. Le probl\u00e8me principal se situe donc dans les interactions entre le tore de Rogowski et le circuit magn\u00e9tique du TC. Il est dimensionnellement impossible dans l\u2019ACB de s\u00e9parer physiquement ces deux \u00e9l\u00e9ments. Le transformateur de courant et le tore de Rogowski doivent donc coexister dans un environnement proche, et cela impacte fortement les performances de mesure demand\u00e9es au tore de Rogowski.<\/span><\/p>\n

June 06, 2024, Junior Seminar<\/h3>\n
Badr CHERQUAOUI<\/span><\/strong>\n

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D\u00e9veloppement de m\u00e9thodes adapt\u00e9es \u00e0 la mod\u00e9lisation de d\u00e9fauts complexes en \u00c9valuation Non Destructive par courant de Foucault\u00a0<\/b><\/h2>\n<\/div>\n

La th\u00e8se porte sur la d\u00e9tection des microfissures dans les centrales nucl\u00e9aires, plus pr\u00e9cis\u00e9ment dans les tubes constituant le g\u00e9n\u00e9rateur de vapeur. Ces tubes, de faible diam\u00e8tre, transportent l’eau du circuit primaire \u00e0 haute temp\u00e9rature et sont soumis \u00e0 de fortes contraintes de pression, ce qui peut entra\u00eener des fissures dues au ph\u00e9nom\u00e8ne connu sous le nom de \u00ab corrosion sous contrainte \u00bb. Des inspections r\u00e9guli\u00e8res de ces tubes sont men\u00e9es pour garantir la s\u00fbret\u00e9 des installations, et l’une des m\u00e9thodes utilis\u00e9es est le Contr\u00f4le Non Destructif par Courant de Foucault (CND-CF), qui permet de v\u00e9rifier l’int\u00e9grit\u00e9 des pi\u00e8ces conductrices. Pour cela, une sonde g\u00e9n\u00e9rant un champ \u00e9lectromagn\u00e9tique est plac\u00e9e \u00e0 proximit\u00e9 de la pi\u00e8ce \u00e0 tester. Comme la pi\u00e8ce est conductrice, des courants induits (courants de Foucault) se d\u00e9veloppent \u00e0 l’int\u00e9rieur. Le flux d’induction magn\u00e9tique est alors capt\u00e9 par deux sondes r\u00e9ceptrices. Lorsque la diff\u00e9rence de flux est significative, cela peut indiquer la pr\u00e9sence d’un d\u00e9faut.<\/span><\/p>\n

L’objectif de la th\u00e8se est d\u2019\u00e9tudier deux aspects : la mod\u00e9lisation du processus de CND-CF \u00e0 l’aide de m\u00e9thodes num\u00e9riques telles que les \u00e9l\u00e9ments finis, afin de pouvoir traiter des configurations aussi complexes que n\u00e9cessaire. Ainsi que la param\u00e9trisation de fissures r\u00e9alistes rencontr\u00e9es dans les tubes du g\u00e9n\u00e9rateur de vapeur. La mod\u00e9lisation des fissures peut n\u00e9cessiter l’utilisation de m\u00e9thodes intrusives. Enfin, cela permettra de mener des \u00e9tudes r\u00e9alistes via le processus de propagation de l’incertitude afin de comprendre et d’identifier plus pr\u00e9cis\u00e9ment les param\u00e8tres influents (PI). Ces simulations peuvent apporter une aide pr\u00e9cieuse aux ing\u00e9nieurs en les aidant \u00e0 interpr\u00e9ter les signaux atypiques d\u00e9tect\u00e9s sur site et donc d’aider \u00e0 la prise de d\u00e9cision.<\/span><\/p>\n

Lea SALEH<\/span><\/strong>\n

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Magnetic Aging of Non-Oriented Electrical Steels Subjected to Thermal Operating Conditions Encountered in Electrical Mobility Applications<\/span><\/b><\/h2>\n<\/div>\n

Electrical mobility applications are becoming increasingly popular today as a part of the move towards net zero emissions.<\/span>\u00a0<\/span>As a result, efficiency improvements in this sector have become essential. The latter calls for significant efforts to be made to improve the energy efficiency of electrical machines used in the automotive industry. One way to achieve this is by optimizing the performance of the machine core. This core, made of\u00a0iron silicon\u00a0electrical\u00a0steel, is subjected to high operating temperatures over time. This triggers atomic diffusion and precipitation mechanisms that can modify the core microstructure, irreversibly deteriorating its magnetic performance and thus increasing its losses (iron losses). This phenomenon is known as magnetic aging.\u00a0<\/span><\/span><\/p>\n

The magnetic aging phenomenon in electrical steels is the\u00a0main focus of my PhD\u00a0thesis, as studying this phenomenon\u00a0can allow to optimize the magnetic performance of the electrical machine by reducing the additional losses that this phenomenon can introduce into the machine core. In fact, as\u00a0my\u00a0PhD\u00a0thesis\u00a0is part of the ANR MASTERMIND2 project, it aims to develop a multi-physical model of magnetic aging mechanisms and their consequences on iron losses while linking the observed magnetic behavior to its underlying microscopic phenomena. Particularly, and in order to achieve the aforementioned aim, my work focuses on the macroscopic behavior of non-oriented iron silicon (Fe-Si) steel samples in response to magnetic aging. Understanding the macroscopic behavior of these steels will allow me to account for the microscopic phenomena underlying magnetic aging and to develop physical models that depict the macroscopic\/microscopic behavior. These models can be, nevertheless,\u00a0useful for\u00a0machine manufacturers in order to produce electrical machines that are more resilient to the effects of magnetic aging.\u00a0<\/span><\/span><\/p>\n

So far, throughout\u00a0the\u00a0first\u00a0research studies\u00a0of my\u00a0PhD\u00a0thesis, the macroscopic models\u00a0investigated\u00a0include the Steinmetz model and the iron loss separation model for the iron losses, as well as the JMAK model for the precipitation phenomenon underlying magnetic\u00a0aging. Moreover, models that can depict the first magnetization B-H curve are still under investigation as\u00a0it\u00a0has been shown to be impacted by magnetic\u00a0aging\u00a0for our studied non-oriented\u00a0electrical steels. The results of the studied macroscopic models are to be further integrated into microscopic models, such as the mean radius model.<\/span><\/p>\n<\/div>\n

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May 07, 2024, Junior Seminar<\/h3>\n

Zhenxin LI<\/span><\/strong><\/p>\n

The ODF-based method for the modeling of the B-H magnetization curves of Grain Oriented Electrical Steels considering mechanical stress<\/span><\/h2>\n<\/div>\n

Grain oriented electrical steels (GOES) are widely used in power transformers to improve energy efficiency and reduce size and weight. GOES are <\/span>characterised<\/span> by their strong magnetic anisotropy, which results in different magnetic properties depending on the direction and intensity of the applied field with respect to the rolling direction (RD). The Orientation Distribution Function (ODF) based approach is a convenient method to describe the anisotropy of the GOES behaviour law due to its ease of identification and implementation. In our previous work, an improvement of the ODF-based model is proposed to increase the modelling accuracy. Recently, we extend the ODF-based model to account for the mechanical stress on the first magnetization curves of a conventional GOES. Furthermore, a simple smoothing method is given to alleviate the oscillation problem found in the ODF-based method.<\/span><\/p>\n

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March 26, 2024, Junior Seminar<\/h3>\n

Othmane MARBOUH<\/span><\/strong><\/p>\n

Capteurs RF MEMS \u00e9lectro-acoustiques passifs et sans fil pour le diagnostic pr\u00e9coce de d\u00e9fauts dans les machines \u00e9lectriques de fortes puissances<\/span><\/h2>\n
Pour garantir la fiabilit\u00e9 et la continuit\u00e9 d’exploitation des machines \u00e9lectriques de forte puissance, il est crucial de prendre en compte les contraintes s\u00e9v\u00e8res auxquelles elles sont soumises pendant leur fonctionnement. Anticiper les op\u00e9rations de maintenance et les \u00e9ventuelles situations de fonctionnement d\u00e9grad\u00e9 n\u00e9cessite une acquisition d’informations d\u00e9taill\u00e9es, souvent au niveau local. Dans cette optique, l’obtention d’informations sp\u00e9cifiques au rotor s’av\u00e8re \u00eatre le moyen le plus fiable pour mettre en place une surveillance et un diagnostic robustes et fiables. Les technologies de capteurs sans fil et sans batterie, combin\u00e9es \u00e0 des m\u00e9thodes avanc\u00e9es d’analyse de donn\u00e9es et de traitement des signaux, peuvent r\u00e9pondre de mani\u00e8re ad\u00e9quate \u00e0 ce besoin sp\u00e9cifique. La technologie des composants SAW, exploitant les ondes acoustiques de surface, offre la possibilit\u00e9 de cr\u00e9er des capteurs enti\u00e8rement sans fil et passifs, r\u00e9pondant ainsi \u00e0 toutes les contraintes \u00e9nonc\u00e9es. Cette approche permet la mesure de diverses grandeurs physiques telles que la temp\u00e9rature, les contraintes m\u00e9caniques et le champ magn\u00e9tique, gr\u00e2ce \u00e0 une ing\u00e9nierie avanc\u00e9e du design.<\/div>\n

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February 15, 2024, Junior Seminar<\/h3>\n

Wei CHEN<\/span><\/strong><\/p>\n

Application des m\u00e9thodes de r\u00e9duction de mod\u00e8le num\u00e9rique pour la quantification d\u2019incertitude en g\u00e9nie \u00e9lectrique<\/h2>\n
Les mod\u00e8les num\u00e9riques bas\u00e9s sur la m\u00e9thode des \u00e9l\u00e9ments finis (MEF) sont d\u00e9sormais la norme pour \u00e9tudier les dispositifs \u00e9lectromagn\u00e9tiques \u00e0 basse fr\u00e9quence. Afin d\u2019acc\u00e9l\u00e9rer la mod\u00e9lisation, on peut remplacer le mod\u00e8le num\u00e9rique complet par un mod\u00e8le r\u00e9duit en utilisant les diff\u00e9rentes m\u00e9thodes de r\u00e9duction. Pour les probl\u00e8mes magn\u00e9toquaistatiques on peut utiliser la m\u00e9thde Cauer ladder network (CLN) qui co\u00fbte peu de temps une fois la construction \u00e0 l\u2019\u00e9tape offline est finie. Nous avons propos\u00e9 une m\u00e9thode pour am\u00e9liorer la robustesse ou la convergence du CLN.<\/div>\n
Nous avons \u00e9galement d\u00e9velopp\u00e9 le CLN multiport en formulation A-T et propos\u00e9 une m\u00e9thode param\u00e9trique simple. Nous avons appliqu\u00e9 le CLN pour mod\u00e9liser le c\u00e2ble HVDC et aussi pour le PCB en utilisant les \u00e9l\u00e9ments coques. Nous avons propos\u00e9 une extension de cette m\u00e9thode sur le probl\u00e8me \u00e9lectroquasistatique (EQS) et l\u2019utilis\u00e9 pour mod\u00e9liser la travers\u00e9e isol\u00e9e.<\/div>\n
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January 09, 2024, Junior Seminar<\/h3>\n

Walid MOHAND OUSSAID<\/span><\/strong><\/p>\n

Investigations des pertes dans les plateaux et <\/span>doigts de serrage dans les machines de fortes puissances<\/span><\/h2>\n
Les dispositifs de serrage sont utilis\u00e9s pour appliquer la pression n\u00e9cessaire au maintien des t\u00f4les du stator dans le cas de machines de grande puissance telles que les grands turbog\u00e9n\u00e9rateurs. Les courants dans les enroulements d’extr\u00e9mit\u00e9 du stator et du rotor induisent des courants de Foucault dans ces pi\u00e8ces de serrage qui sont g\u00e9n\u00e9ralement r\u00e9alis\u00e9es en acier magn\u00e9tique conducteur en raison de contraintes \u00e9conomiques. L\u2019enjeu principal est celui de la connaissance la plus pr\u00e9cise possible des pertes engendr\u00e9es par les courants induits dans les plateaux et doigts de serrage utilis\u00e9s dans les machines \u00e9lectriques de fortes puissances. Plus sp\u00e9cifiquement, les investigations devront analyser l\u2019effet des diff\u00e9rentes composantes du champ magn\u00e9tique ainsi que leurs effets en fonction des mat\u00e9riaux utilis\u00e9s pour les dispositifs de serrage. Pour ce faire, une approche combin\u00e9e exp\u00e9rimentale \/ num\u00e9rique sera mise en \u0153uvre.\u00a0<\/div>\n<\/div>\n<\/div>\n
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<\/div><\/span><\/p>\n2023<\/a>

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December 01, 2023, Junior Seminar<\/span><\/h3>\n

Liwaa ABOUCHAKRA\u00a0<\/strong><\/h3>\n<\/div>\n<\/div>\n
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Int\u00e9gration de mod\u00e8les r\u00e9duits pour l’analyse multiparam\u00e9trique du comportement magn\u00e9to-vibro-acoustique de moteurs \u00e9lectriques<\/span><\/h2>\n
La conception des machines \u00e9lectriques est une t\u00e2che complexe compte tenu de la nature multi-physique des syst\u00e8mes \u00e9tudi\u00e9s ainsi que des nombreuses sources d’incertitudes inh\u00e9rentes \u00e0 chaque discipline. Afin de d\u00e9terminer fid\u00e9lement les grandeurs magn\u00e9to-vibro-acoustique dans un contexte multiparam\u00e9trique, des mod\u00e9les \u00e9l\u00e9ments finis (magn\u00e9tostatique et dynamique des structures) peuvent \u00eatre coupl\u00e9s. Cette d\u00e9marche requi\u00e8re des temps de calcul qui peuvent \u00eatre r\u00e9dibitoires. Ainsi, des techniques de r\u00e9duction de mod\u00e8les sont appliqu\u00e9es \u00e0 chaque mod\u00e8le \u00e9l\u00e9ments finis. Ces derni\u00e8res permettent de conserver des temps de simulation compatibles avec une phase de conception tout en facilitant l’\u00e9tude de d\u00e9fauts (\u00e9lectriques, magn\u00e9tiques, structurels) sur la dynamique du syst\u00e8me.<\/span><\/div>\n

September 11, 2023, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong>Pr. Tetsuji MATSUO (Kyoto University, Japan)<\/span><\/strong><\/p>\n

\n

Tetsuji Matsuo received the B.E., M.E., and Dr. Eng. degrees from Kyoto University, Japan, in 1986, 1988 and 1991, respectively. He became a Research Associate, a Lecturer, and an Associate Professor at Kyoto University in 1991, 2001, and 2003, respectively. He is currently a Professor in the Department of Electrical Engineering, the Graduate School of Engineering, Kyoto University. His current research interests include computational electromagnetics and magnetic material modeling.<\/span><\/p>\n<\/div>\n

Physical\/Phenomenological Modeling of Magnetic Materials<\/span><\/h2>\n
Many macroscopic models of magnetic materials are constructed phenomenologically, where model parameters are determined from measured magnetic property data. To predict magnetic properties without using measured data, a physical model of magnetic materials is necessary. In this seminar, an energy-based multiscale model called \u00ab\u00a0multi-domain particle model\u00a0\u00bb (MDPM) will be discussed. The MDPM is composed of mesoscopic multi-domain particles, and its magnetization state is determined through the local minimization of the total magnetic energy. The influence of magneto-mechanical interactions is represented by the magnetoelastic energy. The MDPM successfully predicts an increase in hysteresis loss due to mechanical stress without fitting to measured data under mechanical stress conditions. Additionally, depending on the audience’s interest, a phenomenological hysteresis model based on the play model will also be addressed.<\/div>\n

July 11, 2023, Junior Seminar<\/h3>\n

Ayoub AINOUZ<\/strong><\/p>\n

Development of an approach combining physical modeling and artificial intelligence for modeling the magnetic properties of electrical steels<\/h2>\n
The energy efficiency of modern motor systems depends on the accuracy and reliability of design tools, particularly those related to electrical steels used in magnetic circuits. However, the mechanical and thermal constraints imposed by manufacturing processes and the use of these motor systems can affect their properties, potentially degrading performance. Traditional approaches to modeling these materials are often complex and slow, while designers need precise and fast models. This thesis proposes integrating Artificial Intelligence (AI), specifically Deep Learning (DL), with multi-physical models of electrical steels to create optimized, faster, and adaptable models for design and optimization procedures. This approach focuses on the development, validation of these models, and their implementation in a numerical calculation code for academic tests.<\/div>\n

June 08, 2023, Junior Seminar<\/h3>\n

Sqalli GHALI <\/strong><\/p>\n

Du mat\u00e9riau \u00e0 la structure magn\u00e9tique par fabrication additive<\/b><\/h2>\n
Additive manufacturing is a flexible and efficient process allowing to create complex components at a reduced expense when compared to conventional methods. While it is not yet extensively employed, additive manufacturing holds promise in the field of electrical engineering, especially for the production of intricate and compact parts. The aim of this PhD is to produce soft ferrite magnetic components\u00a0 with good magnetic properties using additive manufacturing. The research focuses on improving printed materials and taking into account the specific features of printing in the design of new components. One idea is to be able to propose shapes and solutions adapted to the magnetic material and its shaping process through topological optimization tools.<\/span><\/div>\n

Mohamed Reda Saouthi<\/strong><\/p>\n

M\u00e9thodologie de dimensionnement et de supervision \u00e9nerg\u00e9tique d’un smart grid ferroviaire<\/span><\/h2>\n
The integration of decentralized generation and energy storage systems in railway electrification networks is seen as a solution for improving the electrical and energy performance of rail power grids, which are facing a sharp increase in traffic. The aim of this thesis is to define a methodology for the optimal design and energy management of energy production and storage systems in a railway environment. The architecture must be coupled with the energy management of the system to obtain optimized sizing. several approaches will be taken, the first consisting in the realization of a linear optimization model that will simultaneously optimize the dimensions of system components and energy management, the second approach will rely on finer optimization models integrating the non-linearity that naturally appears in the optimization objectives, functional constraints and behavior laws of system components. several optimization schemes will be tested, starting with nested optimization. Finally, we will quantify the variability of the system’s performance in relation to uncertainties about the production of renewable energies and the power consumed by the rolling machines.<\/span><\/div>\n

May 04, 2023, Junior Seminar<\/h3>\n

Joel DRAPPIER <\/strong><\/p>\n

R\u00e9solution num\u00e9rique de probl\u00e8mes \u00e9lectromagn\u00e9tiques non lin\u00e9aires en pr\u00e9sence d\u2019hyst\u00e9r\u00e9sis et anisotropie<\/b><\/h2>\n
Electrical machines are currently the subject of many researches to improve their efficiency by a few percent. One solution consists in using high performance magnetic materials (sheets). However, it appears that the behavior of these materials is highly nonlinear and anisotropic and also presents hysteresis when used in machines. In order to evaluate precisely the efficiency, before the construction of real prototypes, we use numerical modeling that must take into account the nonlinear character of these materials. The L2EP has been developing, with EDF R&D in the context of LAMEL, for many years a computational code, named code_carmel, based on the finite element method to model electromagnetic devices in low frequency. The objective of this PhD is to add to code_carmel the resolution of nonlinear problems integrating anisotropic and hysterical models.<\/div>\n

Fabien DANCOISNE <\/strong><\/p>\n

Characterization and modelling of ferromagnetic material aging for iron losses reduction<\/b><\/h2>\n
\u00ab\u00a0Magnetic aging\u00a0\u00bb refers to the degradation of in-service magnetic properties of Fe-Si steels when submitted to moderate temperatures. This phenomenon is due to the precipitation of carbides or nitrides at electrical machines\u00a0<\/span>operation temperatures of less than 200\u00b0C.\u00a0At the microscopic scale, it was determined that precipitates in the range of 100 nm to 1\u03bcm in size are the most deleterious for magnetic properties and that only Fe-Si alloys with silicon content lower than 3wt% are prone to magnetic ageing.\u00a0These low grade Fe-Si steels correspond however to the largest part (73%) of the current market of non-oriented electrical steels, i.e. 9.8 million tons produced in 2019 in the world. \u00a0Although only scarce attempts have been made to model the precipitation kinetics in this system,\u00a0many precipitation modelling methods have been developed in material sciences.\u00a0<\/span>It appears that models are nowadays available to describe the time evolution\u00a0of precipitates in magnetic steels.\u00a0We can now expect to construct the bridge between microscopic models of precipitation and macroscopic models of the magnetic behavior in order to be able to predict this \u00ab\u00a0magnetic aging\u00a0\u00bb. Integrated to the design process, it will allow to better predict the losses, leading to more efficient and more robust\u00a0electrical machines. It will also give new opportunities to adapt or develop processes during the manufacturing in order to reduce the aging effect according to the operation mode. The aim of the PhD is to develop multi-physical models based on experimental investigations from the microscopic to macroscopic scales of ageing mechanisms in electrical steels and the consequences on\u00a0iron losses.<\/div>\n
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April 06, 2023, Junior Seminar<\/h3>\n

Zhenxin LI<\/strong><\/p>\n

Improvement of the ODF method for the modeling of the B-H magnetization curves of Grain Oriented Electrical Steels<\/h2>\n
Grain-Oriented Electrical Steels (GOES) are widely used in transformers to increase energy efficiency while reducing the volume and weight of such transformers. These GOES are characterized by their strong anisotropy, which leads to different magnetic properties (behavior law and iron losses) depending on the strength and the direction of the applied magnetic field to the rolling direction (RD). To describe the anisotropy of the GOES behavior law, the Orientation Distribution Functions (ODF) based approach shows interesting features regarding ease of identification and implementation. However, a significant oscillation issue in this model at low magnetic field exits. It is recently reported that a high-order ODF method can improve the accuracy of the original model. But the high-order ODF model implies an important number of experimental data according to different directions of the applied field to RD (different magnetization angles) to build a model with sufficient accuracy. In addition, the accuracy also depends on how the input magnetization angles are selected between the RD and the transverse direction (TD). In this work, an optimal algorithm for input magnetization angle selection is proposed for the high-order ODF method. To validate the proposed algorithm, 13 magnetization angles have been measured. A comparative study has been conducted based on the original and the high-order ODF models built with the proposed selected magnetization angles. It is shown that the proposed algorithm can reduce the number of experimental data needed for the ODF model while providing an acceptable global error.<\/div>\n

Idriss NACHETE <\/strong><\/p>\n

Optimal Planar Inductor Design<\/span><\/h2>\n
Magnetic components (transformers and inductors) are essential for the proper functioning of power electronics (EP) converters. Following the emergence of new wide-gap active power components (SiC, GaN), magnetic components now appear to be the technological lock to be unlocked in future years to increase the performance of high-frequency (HF) power converters, in particular in terms of power density and energy efficiency. The aim of this PhD is to work on a new generation of inductance optimized for high current DC\/DC HF applications with, potentially, a high level of ripple. This will involve the development of a sizing and optimal design tool dedicated to those next-gen inductors. For this, it will be necessary to control the magnetic and thermal aspects as well as the losses dissipated by those components. They are based on a combination of printed circuit board (PCB) for the windings and high and low permeability materials for the magnetic core, typically ferrite and FeNi powder. PCBs have many advantages from an industrial point of view, particularly in terms of reproducibility and control of parasitic elements. Low permeability materials make it possible to create distributed air gap zones by limiting the effects of expansion of the field lines around the air gap(s) (on the central leg or on the 3 legs of a core of type E in ferrite), the latter inducing significant localized losses in the conductors near the air gaps.<\/span><\/div>\n

March 08, 2023, Junior Seminar<\/h3>\n

Othmane MARBOUH <\/strong><\/p>\n

Capteurs RF MEMS \u00e9lectro-acoustiques passifs et sans fil pour le diagnostic pr\u00e9coce de d\u00e9fauts dans les machines \u00e9lectriques de fortes puissances<\/h2>\n

Les machines \u00e9lectriques de fortes puissances sont soumises \u00e0 des contraintes s\u00e9v\u00e8res en fonctionnement, afin d’assurer la fiabilit\u00e9 et la continuit\u00e9 d’op\u00e9ration de ces machines, notamment par anticipation des op\u00e9rations de maintenance et de fonctionnement d\u00e9grad\u00e9 si n\u00e9cessaire, il est primordial de disposer d’informations sur ces contraintes, souvent \u00e0 l’\u00e9chelle locale. Par ailleurs, obtenir ces informations au niveau du rotor est le moyen le plus s\u00fbr pour assurer une surveillance et un diagnostic robustes et fiables. Seules les technologies de capteurs sans fil et sans batterie associ\u00e9es \u00e0 des techniques efficaces d’analyse des donn\u00e9es et de traitement des signaux peuvent satisfaire un tel besoin. La technologie des composants SAW, exploitant les ondes acoustiques de surface, permet de concevoir des capteurs sans fil et totalement passifs et permet ainsi de r\u00e9pondre \u00e0 toutes ces contraintes. De nombreuses grandeurs physiques sont mesurables sur cette m\u00eame base technologique moyennant une ing\u00e9nierie avanc\u00e9e du design : temp\u00e9rature, contraintes m\u00e9caniques, champ magn\u00e9tique.<\/p>\n

January 24, 2023, Junior Seminar<\/h3>\n

Walid MOHAND OUSSAID<\/strong><\/p>\n

Investigations des pertes dans les plateaux et doigts de serrage dans les machines de fortes puissances<\/span><\/h2>\n

Les dispositifs de serrage sont utilis\u00e9s pour appliquer la pression n\u00e9cessaire au maintien des t\u00f4les du stator dans le cas de machines de grande puissance telles que les grands turbog\u00e9n\u00e9rateurs. Les courants dans les enroulements d’extr\u00e9mit\u00e9 du stator et du rotor induisent des courants de Foucault dans ces pi\u00e8ces de serrage qui sont g\u00e9n\u00e9ralement r\u00e9alis\u00e9es en acier magn\u00e9tique conducteur en raison de contraintes \u00e9conomiques. L\u2019enjeu principal est celui de la connaissance la plus pr\u00e9cise possible des pertes engendr\u00e9es par les courants induits dans les plateaux et doigts de serrage utilis\u00e9s dans les machines \u00e9lectriques de fortes puissances. Plus sp\u00e9cifiquement, les investigations devront analyser l\u2019effet des diff\u00e9rentes composantes du champ magn\u00e9tique ainsi que leurs effets en fonction des mat\u00e9riaux utilis\u00e9s pour les dispositifs de serrage. Pour ce faire, une approche combin\u00e9e exp\u00e9rimentale \/ num\u00e9rique sera mise en \u0153uvre.<\/span><\/p>\n<\/div>\n<\/div>\n

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<\/div>\n<\/div>\n
<\/div>\n2022<\/a>
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December 13, 2022, Junior Seminar<\/h3>\n

Wei CHEN<\/strong><\/p>\n

Application des m\u00e9thodes de r\u00e9duction de mod\u00e8le num\u00e9rique pour la quantification d’incertitudes en g\u00e9nie \u00e9lectrique<\/h2>\n

<\/p>\n

Dans cette pr\u00e9sentation, je vais pr\u00e9senter\u00a0la m\u00e9thode de Cauer ladder circuit impl\u00e9ment\u00e9 dans Code Carmel ainsi que le sujet de ma th\u00e8se.<\/p>\n

November 17, 2022,\u00a0 Seminar<\/h3>\n

Zuqi TANG<\/strong><\/strong><\/p>\n

Investigation of deep learning applied to computational electromagnetism<\/h2>\n

<\/p>\n

With the development of graphics processing unit (GPU) hardware and algorithm efficiency, deep learning (DL) is shown to be a very powerful tool. It has been widely applied to scientific research and has achieved many satisfactory results. However, the requirement for big data has greatly limited its further application in electrical engineering, where the data generally comes from complex experiments or expensive computations. To address this issue, the feasibility and efficiency of the convolutional neural network (CNN) have been investigated, particularly the U-net. Due to its excellent feature extraction capability, the CNN U-net can be effectively trained with only a small dataset. Different applications have been carried out with U-net, such as surrogate model construction for the computation of coupled magneto-thermal problems, the anisotropic magnetostatic problems, as well as hysteresis loop measurement under different physical considerations. To improve the efficiency of the DL process, the sample selection strategy is optimized by adopting the greedy algorithm. In addition, an adaptive dataset construction approach is put forward to enhance the accuracy of the DL. Besides, physics-informed consideration has been combined recently with the CNN to further improve its interpolation performance and extrapolation capacity under certain physical restrictions.<\/p>\n

June 23, 2022, Junior Seminar<\/h3>\n

Hamza FAROOQ<\/strong><\/strong><\/p>\n

Optimal Sizing of Line Start Permanent Magnet Synchronous Motor (LSPMSM)<\/h2>\n

<\/p>\n

Electric motors consume around 46% of the overall electricity produced around the globe. A significant proportion of this electricity is used to drive motors for direct-start applications such as fans or pumps. Currently, squirrel cage induction motors (SCIM) are widely used in these applications. Recently, due to the regulations of international electrotechnical commission (IEC), there is a trend to replace SCIM by a line start permanent magnet synchronous motor (LSPMSM) to enhance the efficiency of direct-start and fixed speed applications. This thesis involves the development of an analytical model based on a reluctance network (RN) for the optimal design of LSPMSM. The design parameters such as back EMF and d-q axis magnetizing inductances are estimated using the reluctance network approach (RNA) to consider the saturation effect. The developed model is used to determine the transient and steady-state characteristics of LSPMSM. The adopted approach addresses two design challenges: 1) the self-starting ability and 2) IE4 efficiency level during the synchronous regime. The results obtained by the proposed model are compared with the results of the finite element method (FEM) to validate the model. To further assess the robustness of the proposed method, an experimental validation will also be performed.<\/p>\n

May 23, 2022, Junior Seminar<\/h3>\n

Marwane DHERBECOURT\u00a0<\/strong><\/strong><\/p>\n

Caract\u00e9risation des propri\u00e9t\u00e9s m\u00e9caniques de diff\u00e9rents grades d\u2019acier par des techniques de contr\u00f4le non destructif ultrasonore et \u00e9lectromagn\u00e9tique<\/h2>\n

<\/p>\n

Les produits tubulaires commercialis\u00e9s par Vallourec subissent des tests destructifs rigoureux pour s’assurer que leurs propri\u00e9t\u00e9s m\u00e9caniques soient conformes aux normes et aux sp\u00e9cifications des clients. En particulier, les tubes en acier bas carbone sans soudure destin\u00e9s au march\u00e9 du p\u00e9trole et du gaz doivent \u00eatre des produits fiable et durable. Pouvoir mesurer de mani\u00e8re non destructive certaines des propri\u00e9t\u00e9s m\u00e9caniques de ces aciers r\u00e9pondrait \u00e0 un besoin industriel fort. C’est le d\u00e9fi auquel cette th\u00e8se veut r\u00e9pondre : mettre en place une m\u00e9thodologie permettant de mesurer une ou plusieurs grandeurs m\u00e9caniques des nuances d’acier Vallourec, \u00e0 partir de signaux obtenus par des techniques de contr\u00f4le non destructives (CND). Afin de d\u00e9corr\u00e9ler rigoureusement les diff\u00e9rentes contributions qui influencent les mesures exp\u00e9rimentales, une analyse d\u00e9taill\u00e9e des m\u00e9canismes impliqu\u00e9s est n\u00e9cessaire. Aussi, notre attention se porte sur l’\u00e9valuation des propri\u00e9t\u00e9s suivantes : limite d’\u00e9lasticit\u00e9, r\u00e9sistance ultime \u00e0 la traction, duret\u00e9 et contraintes r\u00e9siduelles. Pour ce faire, des techniques CND \u00e9lectromagn\u00e9tiques et ultrasonores prometteuses pour la caract\u00e9risation mat\u00e9riau des aciers sont mises en place.<\/p>\n

April 25, 2022, Junior Seminar<\/h3>\n

Th\u00e9o DELAGNES\u00a0<\/strong><\/strong><\/p>\n

R\u00e9duction de mod\u00e8le num\u00e9rique pour le dimensionnement \u00e9lectromagn\u00e9tique de machines \u00e9lectriques<\/h2>\n

<\/p>\n

Pour \u00e9tudier finement le comportement d\u2019un dispositif \u00e9lectrotechnique hors de son environnement, on utilise g\u00e9n\u00e9ralement des mod\u00e8les num\u00e9riques bas\u00e9es sur une approche de type \u00e9l\u00e9ments finis (EF). Ainsi, il est possible d\u2019obtenir une repr\u00e9sentation fid\u00e8le des distributions de champs magn\u00e9tiques et \u00e9lectriques au sein du mat\u00e9riel \u00e9tudi\u00e9. Cependant, ces mod\u00e8les poss\u00e8dent un grand nombre d\u2019inconnues et g\u00e9n\u00e8rent des temps de calcul importants, qui rendent difficile leur utilisation dans un contexte industriel. Les m\u00e9thodes de r\u00e9duction de mod\u00e8les permettent de r\u00e9duire drastiquement le nombre d\u2019inconnues associ\u00e9 \u00e0 un mod\u00e8le num\u00e9rique. Parmi ces m\u00e9thodes, certaines n\u00e9cessitent des simulations pr\u00e9liminaires effectu\u00e9es avec le mod\u00e8le num\u00e9rique complet, dont certains r\u00e9sultats soigneusement choisis permettent de construire une base r\u00e9duite. Cette base est ensuite utilis\u00e9e pour projeter le syst\u00e8me d\u2019\u00e9quations, ce qui permet de r\u00e9duire le nombre de degr\u00e9s de libert\u00e9s du probl\u00e8me, et introduit une erreur sur l\u2019approximation du r\u00e9sultat. Cependant, lorsque le probl\u00e8me auquel on s\u2019int\u00e9resse pr\u00e9sente des non lin\u00e9arit\u00e9s, la projection seule ne permet pas une r\u00e9duction satisfaisante des temps de calcul, car l\u2019\u00e9valuation des termes non lin\u00e9aires \u00e0 chaque \u00e9tape du calcul est tr\u00e8s couteuse. Dans ce contexte, des m\u00e9thodes d\u2019interpolation permettent de calculer les non lin\u00e9arit\u00e9s \u00e0 certains endroits sp\u00e9cifiquement s\u00e9lectionn\u00e9s du domaine \u00e9tudi\u00e9, et d\u2019interpoler le reste des termes non lin\u00e9aires. Mon travail consiste \u00e0 appliquer les m\u00e9thodes de projection et d’interpolation \u00e0 un probl\u00e8me magn\u00e9todynamique non lin\u00e9aire avec mouvement, pour construire un mod\u00e8le r\u00e9duit d’une machine asynchrone \u00e0 cage d’\u00e9cureuil valide sur une plage de fonctionnement du dispositif.<\/p>\n

February 21, 2022, Junior Seminar<\/h3>\n

Wissem BEKIR\u00a0<\/strong><\/strong><\/p>\n

Prise en compte de la perte d\u2019aimantation r\u00e9versible et irr\u00e9versible des aimants permanents dans les machines \u00e9lectriques<\/h2>\n

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<\/div>\n

<\/p>\n2021<\/a>

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December 13, 2021, Junior Seminar<\/h3>\n

Leysmir MILLAN MIRABAL\u00a0<\/strong><\/strong><\/p>\n

<\/p>\n

Iron loss Modelling of Anisotropic Soft Magnetic Steels in FEM Simulation<\/h2>\n

<\/p>\n

This presentation will serve to introduce an recently develop anisotropic iron loss model from the INRIM laboratory in Italy. The model has been integrated into the finite element software code_Carmel in post-processing, and its implementation have been tested and validated by comparison with experimental results. This developpement are part of the work realized during my PhD thesis.<\/p>\n

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December 13, 2021, Junior Seminar<\/h3>\n

Allaa Eddine BOUMESBAHL\u00a0<\/strong><\/strong><\/p>\n

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Development of metamodels for low-frequency electromagnetic devices<\/h2>\n

<\/p>\n

In recent years, the electric vehicles market is witnessing a large expansion. One of the points of interest is to reduce the electromagnetic noise generated by electric motors. Our work is a part of the project \u00ab\u00a0E-Silence\u00a0\u00bb, consisting in reducing the electromagnetic noise in electric machines without deteriorating the performances or increasing the cost. In order to include the noise issue in the early design phases of a machine, it is required to compute the electromagnetic force for a large set of parameters, which may generate a prohibitive time cost if using a finite element model. A solution is to create a parametric metamodel using model order reduction or interpolation approaches. In this presentation, geometric parametric metamodels are built based on the proper orthogonal decomposition combined with the radial basis functions interpolation method (POD-RBF) and the proper generalized decomposition method (PGD). These approaches are evaluated for academic examples, then applied to the case of an electric machine.<\/p>\n

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November 18, 2021, Junior Seminar<\/h3>\n

Houssein TAHA<\/strong><\/strong><\/p>\n

<\/p>\n

Mise en oeuvre du mod\u00e8le de Darwin par la m\u00e9thode des \u00e9l\u00e9ments finis en vue de mod\u00e9liser les machines \u00e9lectriques \u00e0 des fr\u00e9quences interm\u00e9diaires<\/h2>\n

<\/p>\n

Dans les derni\u00e8res ann\u00e9es, la mod\u00e9lisation des composants magn\u00e9tiques et \u00e9lectriques suscite beaucoup d’int\u00e9r\u00eat dans la recherche scientifique. Un mod\u00e8le magn\u00e9todynamique est suffisant pour d\u00e9crire le comportement des machines \u00e9lectriques dans les basses fr\u00e9quences, mais, avec l’apparition de l’\u00e9lectronique de puissance, les machines sont soumises \u00e0 des tensions hautes fr\u00e9quences, cela n\u00e9cessite une mod\u00e9lisation des isolants surtout en raison du vieillissement auquel ils seront expos\u00e9s. L’objectif de ces travaux est de calculer le champ \u00e9lectrique dans les milieux non conducteurs, en particulier, les effets capacitifs. En effet, vu que les mod\u00e8les classiques tels que la magn\u00e9tostatique et la magn\u00e9to-quasistatique ne prennent pas en compte la mod\u00e9lisation de ces effets, il est indispensable de mettre en \u0153uvre des formulations en potentiels adapt\u00e9es dans le code_Carmel pour calculer simultan\u00e9ment les champs \u00e9lectriques et magn\u00e9tiques, telle que le mod\u00e8le de Darwin. Ce mod\u00e8le est capable de capturer les effets capacitifs-inductifs coupl\u00e9s \u00e0 des fr\u00e9quences int\u00e9rm\u00e9diaires, en particulier, autour de la fr\u00e9quence de r\u00e9sonnance. En revenche, l’\u00e9lectrostatique et l’\u00e9lectro-quasistatique sont parmi les mod\u00e8les connus qui sont capables \u00e0 mod\u00e9liser les effets capacitifs. Diff\u00e9rentes applications industrielles ont \u00e9t\u00e9 pr\u00e9sent\u00e9es afin de valider les r\u00e9sultats de simulation obtenus par le mod\u00e8le de Darwin en les comparant aux r\u00e9sultats de mesures.<\/p>\n

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October 01, 2021, Junior Seminar<\/h3>\n

Ruohan GONG<\/strong><\/strong><\/p>\n

<\/p>\n

Investigation about Deep learning application in the field of computational electromagnetics<\/h2>\n

<\/p>\n

In recent years, deep learning (DL) has been developed rapidly and has conquered many fields and achieved state-of-the-art performance, such as visual recognition, natural language processing, etc. Particularly, convolutional neural network (CNN) has gained tremendous popularity and has been widely used because of its capacity to automatically execute feature engineering on its own. In this presentation, the possibility of applying CNN in the field of computational electromagnetics will be investigated, which can be used as an efficient tool with only a small database. Some typical applications will be presented: the magneto-thermal coupled analysis for transformer, the anisotropy magnetostatics analysis, and the prediction of the hysteresis loops of ferromagnetic materials. The feasibility of the proposed approach are analyzed and discussed in term of the influence of various network hyperparameters. The presented work can provide guides for other DL scenarios in electrical engineering. <\/div> 2020<\/a>

<\/p>\n

<\/p>\n

Mars 05, 2020, Junior Seminar<\/h3>\n

\"\"<\/a> Meryeme Jamil<\/strong><\/p>\n

Meryeme Jamil was born in Rabat, Marocco in 1994. She received the Dipl.-Ing. degree in material engineering (with honors) from ENSMR (Mine Rabat) in 2016, and a master degree titled \u201cMaterial for Energy and Transport\u201d from Paris-Saclay University in 2017. During her master internship, she worked on electrical and magnetic characterization of magnetite poweder in the L2EP laboratory in collaboration with EDF CEIDRE. She is currently a PhD student at the University of Lille and Valeo Powertrain Systems company (CIFRE). She works on the characterization of soft magnetic materials used in electrical machine, mainly the claw pole machine. The aim of her researches is the study of the impact of the machine functioning temperature on the material electromagnetic properties.<\/p>\n

<\/p>\n

Impact of the machine functioning temperature on the material electromagnetic behavior<\/h2>\n

<\/p>\n

Magnetic materials are at the heart of the energy conversion in electrical machines. Their electric and magnetic properties are strongly related to the machine performances and energy efficiency. In order to study and to simulate the electrical machine under its operating conditions, the material electromagnetic behavior should be well known and well characterized not only at room temperature but also at the machine operating temperatures. In fact, during the machine operation, in some hot spots, the magnetic core temperature may reach high temperature levels. As a consequence, the magnetic core properties may considerably change, as for the electrical conductivity to which eddy current losses are directly linked. This modifications can be reversible and disappear once the core has cooled, as it can be irreversible and then speaks of magnetic aging of the material. So, to predict accurately the machine performances, it is necessary to perform both thermal and electromagnetic analyses, starting by characterizing the temperature dependence of the core electromagnetic properties and investigating the magnetic ageing.<\/p>\n

<\/p>\n

<\/div> 2019<\/a>

<\/p>\n

<\/p>\n

November 28, 2019 at 14h00, Invited Seminar (Visiting Ph.D student from Hokkaido University<\/h3>\n

\"\"<\/a><\/strong> Shingo Hiruma (Hokkaido University, Japan)<\/strong><\/p>\n

Shingo Hiruma received the B.E. and M.E. degrees from Hokkaido University, Sapporo, Japan in 2017 and 2019. He is currently a Ph.D. student in Hokkaido University, and a research fellow of Japan Society for the Promotion of Science (JSPS). His research interest is the computational electromagnetism using model order reduction technique.<\/p>\n

<\/p>\n

Model order reduction via Cauer circuit representation of quasi-static Maxwell equations<\/h2>\n

<\/p>\n

In this presentation, we discuss the relation between the quasi-static Maxwell equations and Cauer circuit representation. Starting from a discussion of 1-D model, Kameari\u2019s Cauer ladder network (CLN) method is introduced. It is shown that the CLN method is equivalent to the self-adjoint Lanczos algorithm when the quasi-static Maxwell equations are discretized by the finite element method. From this relation, a new method is formulated which allow to approximate a given transfer function by a continued fraction.<\/p>\n

<\/p>\n

July 8, 2019 at 14h00, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Pr. St\u00e9phane CLENET (ENSAM)<\/strong><\/p>\n

St\u00e9phane Cl\u00e9net is full professor of electrical engineering at Ecole Nationale Sup\u00e9rieure d\u2019Arts et M\u00e9tiers (ENSAM), France. After the completion of his PhD, he was Associate Professor at the University of Lille in 1994 before being appointed as full professor in 2002 at ENSAM. In 2008, he was visiting professor as Fulbright Grantee at the University of Akron (USA) in 2008 and 2014 and at Mc Gill University (Canada) in 2015. From 2007 to 2014, he ran a research team in the field of computational electromagnetics and its applications involving more than 25 professors, post docs and PhD students. From 2016 to 2019, he was the director of the campus ENSAM of Lille. He works on the development of 3D Finite Element Model in low frequency. Since 2004, his research focuses mainly on uncertainty quantification in computational electromagnetics based on stochastic approaches and also on Model Order Reduction technics (POD, PGD\u2026). He is co-author of 85 publications in international journals. He has collaborated with numerous researchers from different universities in France but also from abroad like in Li\u00e8ge (Belgium), Akron (USA), Santa Catarina (Br\u00e9sil), Mc Gill and Laval (Canada), Aalto (Finland), Tsinghua (China), Aachen (Germany). He develops numerous research projects in partnership with major companies like EdF, Valeo, CEA.<\/p>\n

<\/p>\n

Why and how uncertain quantification can be useful in low frequency electromagnetism?<\/h2>\n

<\/p>\n

In some applications represented by very accurate models (the modelling and the numerical errors are negligible), if a gap exists between the measurements, assuming perfect, and the results given by the numerical model, it comes from deviations on input parameters which are not in the \u201dreal world\u201d equal to their prescribed values. The origins of these deviations are numerous and are related to either a lack of knowledge or uncontrolled variations of quantities like temperature, pressure, magnetization. To account for these uncertain deviations on model parameters, the stochastic approach can be used. The model parameters as well as the outputs are then random fields or variables. Several methods are available in the literature to solve stochastic models like sampling methods, perturbation methods or approximation methods. In this presentation, we propose an overview on the solution of stochastic problems in computational electromagnetics. Some applications will be presented in order to illustrate the possibilities offered by this approach Finally, recent numerical techniques proposed in the literature to alleviate the cumbersome needs of resources in terms of memory and time calculation of the stochastic approach particularly due to the the curse of dimensionality appearing when the number of uncertain parameters increases.<\/p>\n

<\/p>\n

<\/p>\n

June 27, 2019, Invited Seminar (Invited Prof. of ULille)<\/h3>\n

\"\"<\/a><\/strong> Dr. Shuai YAN (Institute of Electrical Engineering, Chinese Academy of Science)<\/strong><\/p>\n

Shuai Yan received the B.S. degree in Mathematics and Applied Mathematics from Beijing Normal University in 2007 and the M.S. degree in Computational Mathematic also from Beijing Normal University in 2010. She received the Ph.D. degree in Computational Optics in University of Erlangen-Nuremberg in Germany, 2014. After that, she joined the Chinese Academy of Science as an Associated Researcher. She has published more than ten papers in international journals. Her current research interests are model reduction techniques for full wave analysis and optimization of high frequency RFID systems and also efficient solvers for multi-physics analysis in integrated circuit design.<\/p>\n

<\/p>\n

Title: Model Order Reduction with POD\/PGD and Related Applications in Computational Electromagnetics<\/h2>\n

<\/p>\n

Modern industrial development brings new challenges to computational electromagnetics by introducing extremely computationally intensive problems and the needs of real-time simulation. Model order reduction can help with tacking these challenges from two perspectives. One is to solve the problems with less computational cost in time and memory, another is to build a compact parametric model from an \u201coffline process\u201d which can be used to achieve a fast solution during an \u201conline process\u201d. POD and PGD are two important MOR techniques that attracts much attention in recent years. In this presentation, I will discuss about the implementation of POD and PGD in both static and high frequency problems. Issues including complex domains, high dimensionality as well as adaptive algorithms will be addressed.<\/p>\n

<\/p>\n

<\/p>\n

June 13, 2019, Junior Seminar<\/h3>\n

\"\"<\/a><\/strong> Dr. Emna JAIEM <\/strong><\/p>\n

Emna Ja\u00efem obtained a PhD degree in Applied Mathematics from Tunis El Manar University, Tunis, Tunisia in July 2016. During her PhD thesis, she investigated the geometrical inverse problem related to the identification of defects in mechanical structures from, on the one hand, overdetermined boundary data and, on the other hand sub-Cauchy data. Indeed, her research fields include shape optimization (shape derivative, topological derivative, level set method, …). In September 2017, her work was recognized with the TWMA (Tunisian Women Mathematicians’ Association) award for the best PhD thesis in Applied Mathematics for Tunisian women<\/span><\/a><\/span>. She is currently a postdoctoral researcher at L2EP working on the numerical analysis of electromagnetic fields and more precisely on spectral methods (Harmonic Balance Method).<\/p>\n

<\/p>\n

Harmonic balance finite element method applied to electromagnetic problems<\/h2>\n

<\/p>\n

The time stepping approach is a well-known numerical method to model electromagnetic problems. However, it can present some drawbacks since it requires expensive computation time in the case of a large transient state. To overcome this problem, harmonic balance method can be used. In the first part of the presentation, we introduce this method. Then, we apply it for electrical machines taking into account the motion. Furthermore, we compare the solutions obtained by the harmonic balance finite element method coupled, on the one hand, with the A formulation and, on the other hand, with \u03a9 formulation with those obtained by the reference method; namely the time stepping finite element method.<\/p>\n

Since harmonic balance method relies on the representation of time-periodic function by a truncated Fourier series, the problem of harmonics selection is discussed in the second part of the presentation. A novel approach based on time residual is proposed to solve a nonlinear magnetostatic problem using harmonic balance method.<\/p>\n

<\/p>\n

<\/p>\n

June 07, 2019, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Pr. Mircea M. RADULESCU (Universit\u00e9 Technique de Cluj-Napoca, Roumanie) <\/strong><\/p>\n

Mircea M. Radulescu received the Dipl.-Ing. degree in electrical engineering (with honors) from the Technical University of Cluj-Napoca, Cluj-Napoca, Romania, in 1978, and the Ph.D. degree in electrical engineering from the Polytechnic University of Timisoara, Timisoara, Romania, in 1993. Since 1983, he has been with the Faculty of Electrical Engineering, Technical University of Cluj-Napoca, where he is currently a Full Professor in the Department of Electric Machines and Drives, and Head of the Special Electric Machines and Light Electric Traction (SEMLET) Research Laboratory. He is the author or co-author of more than 180 published scientific papers in refereed technical journals and international conference and symposium proceedings. His teaching and research activities include classical and special electric machines; computer-aided design of electromechanical devices; design and control of small electronically-commutated motors; actuators and mechatronic drives; light electric traction systems; design and analysis of small-scale renewable energy equipment. He was an Invited Professor at Swiss Federal Institute of Technology Lausanne \u2013 EPFL, Switzerland; Helsinki University of Technology, Espoo, Finland; RWTH Aachen, Aachen, Germany; University of Akron, Akron, USA; University \u2018Pierre et Marie Curie\u2019, Paris, France; University of Picardie \u2018Jules Verne\u2019, Amiens, France, and Centrale Lille, Villeneuve d\u2019Ascq, France. He is an Associate Editor of the international scientific quarterly \u2018Electromotion\u2019. His biography is listed in several editions of \u2018Who\u2019s Who in the World\u2019 and \u2018Who\u2019s Who in Science and Engineering\u2019. Prof. Radulescu is a Senior Member of IEEE, USA and a Member of IET, UK. He is also a member of the International Steering Committees of several conferences and symposia in the field of electric motor drives, electric traction, and renewable energy.<\/p>\n

<\/p>\n

Nouvelles topologies de g\u00e9n\u00e9rateurs \u00e9lectriques pour micro-\u00e9oliennes<\/h2>\n

<\/p>\n

Contenu<\/p>\n

Introduction aux \u00e9oliennes \u00e0 petite \u00e9chelle Exigences de conception des g\u00e9n\u00e9rateurs \u00e9lectriques pour les micro-syst\u00e8mes de conversion d’\u00e9nergie \u00e9olienne Analyse comparative de la conception des nouvelles topologies des micro-a\u00e9rog\u00e9n\u00e9rateurs \u00e9lectriques Conclusion<\/p>\n

<\/p>\n

<\/p>\n

June 04, 2019, Visiting Professor from Shanghai Maritime University<\/h3>\n

\"\"<\/a><\/strong> Dr. Hao CHEN (Shanghai Maritime University, China) <\/strong><\/p>\n

Hao Chen (M\u2019 17) was born in Jiangsu, China, in 1985. He received the B.E. degree in automation from Shanghai Maritime University, Shanghai, China, the M.E. and Ph.D. degrees in electrical engineering from the University of Nantes, Nantes, France, in 2008, 2010, and 2014, respectively. He is currently a lecture with Shanghai Maritime University China. His research interests include designing, modeling and control of electrical machines, and wind or tidal energy conversion system.<\/p>\n

<\/p>\n

Research on power electronics and electric drives at Shanghai Maritime University<\/h2>\n

<\/p>\n

In the presentation, I firstly introduce Shanghai Maritime University and the colleges briefly. Then, I will focus on the introduction of the department of electrical engineering, especially the research institute of power drive and control. At last, I will present some personal research interests.<\/p>\n

<\/p>\n

<\/div> 2018<\/a>

<\/p>\n

<\/p>\n

December 06, 2018, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Pr. Jiaxin YUAN (Wuhan University)<\/strong><\/p>\n

Jiaxin Yuan (M\u201907) was born in Nanchang, China, on June 10, 1981. He received the B.S. and Ph.D. degrees from the School of Electrical Engineering, Wuhan University, Wuhan, China, in 2002 and 2007, respectively. From 2007 to 2009, he was a Lecturer with Wuhan University, where he was engaged in research and development of STATCOM and DSP inverter control and, since 2007, he has been engaged in power electronics system control, power quality issues, and application and control of inverters. From 2016, he got the full Professor position at the School of Electrical Engineering, Wuhan University.<\/p>\n

<\/p>\n

The Present Status and Future of Fault Current Limiter in High Voltage Power System<\/h2>\n

<\/p>\n

The first part of the presentation gives some brief introduction to Wuhan University, as well as the Department of Electrical Engineering and Automation. The second part will introduce the Present Status and Future of Fault Current Limiter in High Voltage Power System. Nowadays, the short circuit fault current increasing rapidly in all of the worlds. The short circuit fault current in some grid exceeds the capacity of the breaker, seriously threatening the safety and stability of the power grid. So the presentation will explain the principle of rapid increase in the short circuit current, analysis the different methods to reduce the short circuit current. At last, the presentation will propose a novel fault current limiter.<\/p>\n

<\/p>\n

<\/p>\n

November 29, 2018, Invited Seminar<\/h3>\n

\"=""\"<\/a> Dr. Alain BOSSAVIT<\/strong><\/p>\n

<\/p>\n

Sur l’approche g\u00e9om\u00e9trique des \u00e9quations de Maxwell et de leur discr\u00e9tisation<\/h2>\n

<\/p>\n

<\/p>\n

Nomember 20, 2018, LAMEL Day(Pl\u00e9ni\u00e8re du LAMEL)<\/h3>\n

<\/p>\n

Schedule<\/h2>\n

<\/p>\n

<\/p>\n

10h00-10h30 : K\u00e9vin DARQUES : Mod\u00e9lisation de la tension d’arbre 10h30-11h00 : Sylvain SIHAB : Mod\u00e8les de pertes magn\u00e9tiques 11h00-11h30 : Rihad CHERIF : Solveurs Non lin\u00e9aire 11h30-12h00 : Loic Chevallier et Juien KORECKI : Code_carmel 14h00-14h30 : Emna JAIEM : Mouvement pour M\u00e9thode Spectrale 14h30-15h00 : Lyd\u00e9ric DEBUSSCHERE : Techniques de remaillage 15h00-15h30 : Guillaume CARON : R\u00e9duction de mod\u00e8les<\/p>\n

<\/p>\n

<\/p>\n

November 09, 2018, Invited Seminar<\/h3>\n

\"=""\"<\/a><\/strong> Oualid MESSAL<\/strong><\/p>\n

Oualid Messal received the Ph.D. degree in Electrical Engennering from Lyon University in Dec. 2013. From 2013 to 2014, he was a Temporary Assistant Professor of Electrical and Computer Engineering with Lyon1 University. From Sep. 2014 to Aug. 2018, he was a CNRS postdoc researcher at the Grenoble Electrical Engennering Laboratory. During his thesis and postdoc, he has been the principal investigator on a number of successful research programs including Aperam company, Renault, Altair, Schneider Electric, etc. The primary focus of his investigations is the area of magnetic materials for electrical engineering applications. From Sep. 2018, he is associate professor at Lille University where conducts research at the Lab of Electrical Engineering and Power Electronics.<\/p>\n

<\/p>\n

Characterization and modeling of soft magnetic materials for electromagnetic applications<\/h2>\n

<\/p>\n

<\/p>\n

<\/p>\n

<\/p>\n

September 14, 2018, Visiting Professor from Xi\u2019an Jiaotong University<\/h3>\n

\"\"<\/a><\/strong> Pr. Shuhong WANG (Xi\u2019an Jiaotong University) <\/strong><\/p>\n

Prof. Shuhong Wang was born in China, in 1968. He received his Ph.D. degree in Electrical Engineering from Xi\u2019an Jiaotong University, in 2002. Currently, he is a Professor with School of Electrical Engineering, Xi\u2019an Jiaotong University. He is a senior member of IEEE (No. 92041995) and a board member of Council of Applied Superconducting Technology of China Electrotechnical Society. His research interests include theory, computation and application of electromagnetic fields and design, simulation and optimization of electrical apparatus. He presided one National Science and Technology Major Project, two projects supported by the National Natural Science Foundation of China and tens of projects supported by electric power company. He is the author of more than 100 technical papers as well as 6 professional books.<\/p>\n

<\/p>\n

Research on short circuit dynamic characteristics and mechanical life of power transformer winding (Ph.D. student: Shuang WANG)<\/h2>\n

<\/p>\n

The dynamic characteristics of transformer windings under short circuit state are of great significance to the safe operation of transformers. The electromagnetic properties of a 110 kV transformer, including leakage magnetic field and electromagnetic force of windings, are calculated using finite element method (FEM). During the short circuit, the power transformer windings\u2019 dynamic force, displacement and stress are calculated. The characteristics of windings\u2019 dynamic motion process because of the big electromagnetic force are analyzed. The mechanical life model of transformer windings is established based on the mechanical experiment of the winding material. The analysis method and research results can provide reference for taking measures to enhance the ability to withstand short circuit of transformer windings.<\/p>\n

<\/p>\n

Study on the Electromagnetic Field in HVDC\/AC Hybrid Submarine Cable Tunnel (Ph.D. student: Ting ZHU)<\/h2>\n

<\/p>\n

There is a rapidly increasing on the volume of HVDC cable over the last twenty years. To reduce the cost of cable tunnel construction, it is very common that the HVDC cable is laid in the original alternating current (AC) cable tunnel. In the Xiang\u2019an tunnel of Xiamen, China, the operation and maintenance personnel have an electric shock when contacting the sandboxes in DC side during the work period. A model of the tunnel with \u00b1320kV DC cable lines and a 220kV AC cable line is shown in this presentation. The distribution of power frequency electromagnetic field in the HVDC\/AC hybrid submarine cable tunnel is studied by simulation and measurement, and the cause of the accident that the operation and maintenance personnel have an electric shock in the tunnel is analyzed, which provides guidance for the safe operation of the cable.<\/p>\n

<\/p>\n

Visiting Schedule<\/h2>\n

<\/p>\n

<\/p>\n

09h40-10h00: Welcome coffee 10h00-10h30: Presentation of L2EP Laboratory and of \u201cOMN\u201d Team 10h30-11h00: Research on short circuit dynamic characteristics and mechanical life of power transformer winding 11h00-11h30: Study on the Electromagnetic Field in HVDC\/AC Hybrid Submarine Cable Tunnel 14h00-14h30: Magnetic materials characterization 14h30-15h00: Visiting Platform \u2013 Magnetic Materials 15h00-16h00: Discussions \/ exchanges on potential collaboration projects<\/p>\n

<\/p>\n

<\/p>\n

September 4, 2018, Visiting Professor from Zhejiang University<\/h3>\n

\"\"<\/a> Pr. Shiyou YANG (Zhejiang University)<\/strong><\/p>\n

Shiyou Yang has been a full Professor at the College of Electrical Engineering, Zhejiang University since 2001. Currently, his research interests include computational Electromagnetics in both high and low frequency domains, the application of numerical techniques in electronic and electromagnetic devices. He has worked in the Department of Electrical and Computer Engineering, Duke University, USA, from November 2007 to May 2008 as a visiting scholar; the Department of Electrical Engineering, the Hong Kong Polytechnic University, Hong Kong, as a postdoctoral research fellow, research and senior research fellows from periods of September 2006 to February 2007, September 2005 to November 2005, March 2003 to February 2004, September 1999 to August 2001; Sau Paulo State University, Brazil, from September 1998 to August 1999 as a postdoctoral research fellow; and Universit\u00e9 Pierre et Marie Curie, France, from September 9, 2017 to October 8, 2017 as a visiting Professor. So far, he has published more than 150 papers in referred international conference and journals, and more than 100 in high rank international journals.<\/p>\n

<\/p>\n

Visiting Schedule<\/h2>\n

<\/p>\n

13:15 \u2013 13:30 Presentation of \u201cOMN\u201d Team 13:30 \u2013 13:45 Presentation of EEA department 13:45 \u2013 14:00 Presentation of L2EP Laboratory 14:00 \u2013 14:15 Presentation of \u201cControl\u201d Team 14:15 \u2013 14:30 Model order reduction 14:30 \u2013 14:45 Sophemis Optimization Platform 15:00 \u2013 15:20 Visiting Platform \u2013 Electrical Vehicle 15:20 \u2013 15:40 Visiting Platform \u2013 Power Electronics 15:40 \u2013 16:00 Visiting Platform \u2013 Materials<\/p>\n

<\/p>\n

<\/p>\n

August 31, 2018, Invited Seminar<\/h3>\n

\"\"<\/a> Pr. Chijie ZHUANG (Tsinghua University)<\/strong><\/p>\n

Chijie Zhuang received the B.Eng. and Ph.D. degrees from the Department of Electrical Engineering, Tsinghua University, Beijing, China, in 2006 and 2011, respectively. After a 2-year post-doc program, he became an assistant professor in Tsinghua University, where he was promoted to be an associate professor in 2015. His research interest includes air gap discharge and lightning protection, as well as numerical simulations for problems in electrical engineering. He has published about 30 papers in international peer-reviewed journals. He was the secretory of CIGRE C4.26 working group (WG), and is the secretory of C4.45 WG, a member of IEEE P2426 WG. He also serves as an associate editor of High Voltage published by IET and CSEE Journal of Power and Energy Systems published by IEEE.<\/p>\n

<\/p>\n

Electrical Discharges: Experiment and Simulations\u2014\u2014Two Examples<\/h2>\n

<\/p>\n

A leader is an electric discharge mechanism in long-air-gap discharges, which is generally described by a set of convection-diffusion equations, Poisson\u2019s equation and Navier-Stokes equations. We report the shockwave phenomenon in an air-gap leader discharge observed using a Mach-Zehnder interferometer with a time resolution of several microseconds. The continuous temporal evolution of the shock wave and the plasma channel was recorded and reproduced with a thermo-hydrodynamic model discretized by MUSCL and TVDRK schemes, with the measured current as the model input. The simulation results for the shock wave front positions and the plasma channel radius showed good consistency with the experimental measurements. Detailed thermal parameters obtained through the simulation showed that continuous energy injection by the current results in a temporary over-pressure process in the plasma channel and produces the shock wave.<\/p>\n

<\/p>\n

<\/p>\n

July 2, 2018, Invited Seminar<\/h3>\n

\"\"<\/a> Pr. Anouar BELAHCEN (Aalto University)<\/strong><\/p>\n

Anouar Belahcen (M\u201913-SM\u201915) received the M.Sc. (Tech.) and Doctor (Tech.) degrees from Helsinki University of Technology, Finland, in 1998, and 2004, respectively. He is now Professor of Energy and Power at Aalto University, Finland and Visiting Professor of electrical machines at Tallinn University of Technology, Estonia. His research interest are numerical modelling of electrical machines, magnetic materials, coupled magnetomechanical problems, magnetic forces, magnetostriction, and fault diagnostics of electrical machines.<\/p>\n

<\/p>\n

Research at Aalto University, with an emphasis on the magnetomechanical coupling<\/h2>\n

<\/p>\n

The first part of the presentation introduces some of the research subjects at Aalto University, Department of Electrical Engineering and Automation. The second part focuses on the research related to the magnetomechanical coupling in electrical steel. Here a measurement setup for rotational magnetic field and arbitrary mechanical stress will be presented together with the results of measurements on a non-oriented electrical sheet. Further, a model for the magnetomechanical coupling will be presented and discussed. The magnetic properties of electrical steel sheets are known to be highly stress dependent. During the manufacturing processes and operation of these devices, multi-axial stresses are exerted on the core laminations. The performance of the electrical machines is then signi\ufb01cantly affected by these multi-axial loadings. In order to be able to design efficient devices and analyze the existing ones with better accuracy, the dependency of the core losses on the multi-axial stresses should be studied comprehensively. Yet another important issue is the effect of these loading on the noise and vibrations of electrical machines.<\/p>\n

<\/p>\n

<\/p>\n

Juin 21, 2018, Junior Seminar<\/h3>\n

\"\"<\/a> Reda EL BECHARI<\/strong><\/p>\n

Reda El Bechari was born in Taza, Morocco, in 1993. He received his Master degree from ENSAM Lille, in 2016. Jointly, he has got an engineering degree (Industrial Engineering) from ENSAM Casablanca, Morocco. He is currently a Ph.D. student with L2EP in Centrale Lille. His research fields include numerical methods of electromagnetic fields, robust design and reliability based design optimization for electromagnetic devices.<\/p>\n

<\/p>\n

Approaches to Design Optimization of Electromagnetic Devices using Finite Element Method<\/h2>\n

<\/p>\n

The increasing constraints on the design of electromagnetic devices require numerical tools that are able to finely model the electromagnetic fields in the studied domain. Finite Element Method (FEM) is the most used tool to satisfy such a requirement. However, it may turn out that this tool is very expensive in computational time due to nonlinear behavior, 3D geometries, and time dependency. Thus, its usage for optimization, i.e. iterative process, should be made with caution since only a limited number of evaluations of the simulation tool are possible. Thus, the use of some specific algorithms may not be possible in a limited time, e.g. genetic algorithms, that require many evaluations of the FEM code. On the other hand, gradient-based algorithms cannot be used to their full potential due to the re-meshing error that may appear when computing the gradient using finite difference. There exist two approaches. A non-intrusive approach that considers the FEM simulation as a black-box and constructs cheap meta-models to reduce the computational burden while refining only in promising regions. And a second approach aims to exploit the derivative of quantities of interest computed from the finite element code by using the adjoint method to be able to use gradient-based algorithms.<\/p>\n

<\/p>\n

<\/p>\n

Juin 1, 2018, Junior Seminar<\/h3>\n

\"\"<\/a> K\u00e9vin DARQUES<\/strong><\/p>\n

K\u00e9vin Darques was born in Neufch\u00e2teau, Vosges, France in 1990. He received his Master of Electrical Engineering from Lorraine University in 2014. During is degree, he had the opportunity to work with the Jeumont Electric company to study the permanent magnet losses in electrical machines with concentrated windings. After that, he started a Ph.D. at the University of Lille and EDF R&D (CIFRE). His work focused on the analysis of the shaft voltage of high-power turbogenerators. His research topic focuses toward His research topic focuses toward the finite element analysis of electrical machines.<\/p>\n

<\/p>\n

Contribution to the shaft voltage modeling of high-power generators<\/h2>\n

<\/p>\n

In large turbo-generators, shaft voltage exists due to the inherent minor imperfections in the construction of the machine or material imperfections but also to defects such as eccentricities or rotor shorts circuits. Therefore, its analysis can constitute a variable to be used to diagnosis some machine defects. A first step consists in determining in an accurate way the effect of these defects on the shaft voltage. In this aim, a didactic analysis is carried out with the help of numerical model based on 2D FEM. Two high-power non-salient pole synchronous generators of 2 and 4 poles are studied. The study is carried out gradually, first on a simplified structure and then introducing the effect of the stator slots, the parallel coupling, the load or eddy currents in the damper bars have been investigated. The obtained results are analysed in order to clearly determine the impact of each variable.<\/p>\n

<\/p>\n

<\/p>\n

May 23, 2018, Invited Seminar<\/h3>\n

\"\"<\/a> Antonio Wendell de Oliveira Rodrigues (IFCE)<\/strong><\/p>\n

Antonio Wendell de Oliveira Rodrigues a soutenu une th\u00e8se de l’Universit\u00e9 des Sciences et Technologies de Lille (France) sur un sujet relatif \u00e0 l’informatique haute performance utilisant les GPU avec une approche IDM pour la simulation des machines \u00e9lectriques, cofinanc\u00e9e par le Minist\u00e8re de l’\u00c9ducation Fran\u00e7aise et la soci\u00e9t\u00e9 VALEO. Il a fait un stage postdoctoral en gestion de l’innovation au Coll\u00e8ge Lambton (Canada) et est titulaire d’un dipl\u00f4me en ing\u00e9nierie \u00e9lectrique avec sp\u00e9cialisation en informatique de l’Universit\u00e9 F\u00e9d\u00e9rale de Cear\u00e1. Enseignant-chercheur \u00e0 l\u2019IFCE (Br\u00e9sil) dans les domaines de recherche suivants : ing\u00e9nierie logicielle, calcul haute performance, r\u00e9seaux informatiques et syst\u00e8mes distribu\u00e9s. Il travaille dans divers projets de RD&I en utilisant le traitement d’images pour l’identification des patterns, l’utilisation de drones pour l’inspection par imagerie thermique, SmartGrid, IoT, l’apprentissage de machine…<\/p>\n

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RD&I et projets appliqu\u00e9s au secteur \u00e9lectrique au Br\u00e9sil<\/h2>\n

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Antonio Wendell de Oliveira Rodrigues nous fera un panorama des projets de RD&I pour le secteur de la g\u00e9n\u00e9ration, la transmission et la distribution d’\u00e9nergie au Br\u00e9sil via une approche calcul scientifique, bas\u00e9e sur des techniques de traitement d’images pour la reconnaissance d\u2019objets, le calcul haute performance, l\u2019intelligence artificielle, IoT et autres.<\/p>\n

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April 26, 2018, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Brijesh Upadhaya (Aalto University)<\/strong><\/p>\n

Brijesh Upadhaya was born in a small town of Saptari district, Nepal, in 1986. He received his Bachelor of Engineering (Electrical Engineering) degree from Kathmandu University, in 2008. After receiving the B.Eng. degree he joined the alternative energy promotion center (AEPC, Ministry of Environment), and worked as a technical officer for the rural energy development program in the hilly and mountaineous districts of Nepal. In year 2010 he participated for the Fredkorpset Norway (:fK) south-south exchange program as an electrical engineer for the development of the micro-hydro power, in Laos. During his assignment in Laos he was hosted by the Sunlabob Renewable Energy Ltd. Brijesh had an opportunity to work for the energy demand forcast in southern Laos, detail feasibility study of the micro and pico hydro systems in Northern Laos, design of the solar home systems for the projects in Cambodia and Marshall Islands. After completion of the project in Laos, Brijesh started his Master of Science degree in electrical engineering at Aalto University, Finland, in 2012. He received his M.Sc. (Tech) degree in 2014 with a major in electrical systems and minor in electrical drives. Brijesh enrolled as a doctoral student in the research group of electromechanics at the Aalto University and he is currently working towards his doctor of science degree in electrical engineering. His research topic focuses toward the development of a vector hysteresis model that take into account the magnetic anisotropy. The anisotropic model should be suitable for the magnetic field analysis of the mangetic devices.<\/p>\n

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Modeling of the magnetic anisotropy in a soft magnetic material<\/h2>\n

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A non-oriented (NO) electrical steel sheet present a certain level of magnetic anisotropy. Unlike a grain oriented (GO) electrical steel, the degree of magnetic anisotropy found in the NO electrical steels vary considerably, between low-to-medium levels. A large percentage of the electrical applications utilize the NO electrical steel sheet, such as the rotating electrical machines. Thus, for an efficent design of the electrical applications, an accurate magnetic material model have become increasingly important. For this reason, the magnetic material model capable of describing a weakly anisotropic NO electrical steel sample has been studied in this work. This studied model is an extension of the phenomenological Jiles-Atherton hysteresis model. Furthermore, the extended model of the magnetic anisotropy is analysized, and the simulation results from this model has been compared with the measured magnetic charecteristic. Moreover, the numerical challanges has been studied, regarding the implementation of the vector Jiles-Atherton hysteresis model in a 2D finite element analysis.<\/p>\n

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April 20, 2018, (C2EI Day)<\/h3>\n

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Schedule<\/h2>\n

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Moustafa AL EIT : \u00ab\u00a0Exploitation of the geometrical periodicity of electrical machines in the FE modeling\u00a0\u00bb<\/p>\n

Jian ZHANG : \u00ab\u00a0modeling and experiment validation of squirrel cage asynchronous machine with and without faults\u00a0\u00bb Emna JAIEM : \u00ab\u00a0Spectral finite element method to solve magnetostatic problem taking into account the movement\u00a0\u00bb<\/p>\n

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April 19, 2018, Junior Seminar<\/h3>\n

\"\"<\/a><\/strong> Sylvain SHIHAB <\/strong><\/p>\n

Sylvain Shihab receive his Master and Phd in condensated matter physics at the Pierre and Marie Curie University in 2012 and 2015. He worked mainly on the magnetization dynamics in the diluted magnetic semiconductor (Ga,Mn)(As,P). He is currently research engineer at the L2EP laboratory. His main researches are on the study and the characterization of soft magnetic steel alloys used in electrical machine to improve models describing magnetization behavior law.<\/p>\n

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Characterization and modeling of magnetic steels alloys used in electrical machines<\/h2>\n

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Magnetic materials are the heart of electrical machine for mechanical to electrical energy conversion. Thus, an improvement of magnetic materials performance lead to an improvement of the electrical machine. To better understand all relevant materials parameters which have an impact on the magnetic properties, it is necessary to characterize materials in various experimental conditions. Then, starting from our observations, we can propose and improve models of magnetic behavior laws. During this seminar, I\u2019ll present you our work on the magnetic characterization of non-oriented sheets and bulk magnetic steel alloys, on the conductivity measurement and on the improvement of magnetic losses model.<\/p>\n

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February 15, 2018, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Ruohan GONG (Wuhan University) <\/strong><\/p>\n

Ph.D. candidate of Electrical Engineering School of Wuhan University. Graduated from Physics and Technology School of Wuhan University with BE degree at 2012. Worked as an associated researcher in High voltage and Insulation Center of Wuhan University form 2012 to 2018. Major in Lightning-protection and Grounding, Electrical Engineering Materials, Multi-Physics Coupling Simulation of electrical devices and Inversion problem.<\/p>\n

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Study on Hot-spot Temperature Calculation and Inversion Detection Method of Oil-immersed Transformer<\/h2>\n

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Power transformers are one of the most important equipment of the electrical power system. The operating reliability of transformers has a close influence on security and stability of power systems. The end of the life span of power transformers is most due to the loss of their normal insulation, which is very much dependent on the highest temperature occurred in any part of a winding insulation system, as known as hot spot temperature (HST). Thus, getting the values and location of HST is significant to meet the goals of maximizing the load ability, improving the effective lifetime and lowering the total cost associated with transformer operation and maintenance. Some works focused on this topic has been developed as follows: (1) Considering the complicated and special solid-liquid-gas structure of oil-immersed transformer, the heat dissipation process inside transformer including heat conduction and convection is investigated by multi-physics coupling analysis. The validity and accuracy of calculation model is verified by temperature rise test. (2) According to the temperature and velocity distribution analysis of inner transformer, an inverse detection method of HST based on support vector regression(SVR) is put forward. This method takes load and tank temperatures as input characteristics. The relative error of HST steady state temperature inversion is less than 3%. (3) On the basis of steady inversion, an improved HST transient calculation method based on thermal-electrical analogy and IEC standard is proposed. The thermodynamic parameters of this model are estimated by Levenberg-Marquardt(LM) method. This model has been successfully applied to transformers with different voltage classes, capacities and structures. The maximum temperature difference is less than 3\u2103.<\/p>\n

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<\/div> 2017<\/a>

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November 13, 2017, Invited Seminar<\/h3>\n

\"\"<\/a><\/strong> Pr. Shuhong WANG (Xi\u2019an Jiaotong University) <\/strong><\/p>\n

Shuhong Wang (M\u201911\u2013SM\u201913) received the B.E., M.E., and Ph.D. degrees in electrical engineering from Xi\u2019an Jiaotong University, Xi\u2019an, China, in 1990, 1993, and 2002, respectively. He is currently a Professor with the school of Electrical Engineering, Xi\u2019an Jiaotong University. His research fields include numerical analysis of electromagnetic field and multiphysics problems, design and optimization of electromagnetic devices, measurement and modeling of properties of novel magnetic materials, the analysis and application for high temperature superconductivity.<\/p>\n

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Extended Finite Element Method in Electromagnetic Fields<\/h2>\n

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In some situations, the classic finite-element method (CFEM) uses the shape functions for interpolation and does not account easily for regions of discontinuity and singularity in electromagnetic problems, such as the magnetic field and eddy current distribution in one silicon sheet of magnetic core, the electric field distribution near the crack tip in the electrical insulation material. The extended finite element method (XFEM) is able to incorporate the local enrichment into the approximation space within the framework of CFEM, the resulting enriched space is then capable of capturing the non-smooth and singularity solutions. The interface between two materials, which may cross through the element, can be described by using level-set functions and Guass integration is applied to construct the stiffness matrix of XFEM. Two numerical examples demonstrate that XFEM has some advantages for electromagnetic field analysis of discontinuous and singular solutions comparing with CFEM. The XFEM can not only improve the computational accuracy, but also save computation memory and time.<\/p>\n

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<\/div><\/p>\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

The research team OMN specializes in various numerical methods associated with electromagnetic field computation. We regularly organize the Junior Seminar, where presentations are given by our Ph.D. students and postdocs, and we occasionally host an Invited Seminar featuring presentations by external researchers. If you are interested in giving a talk or exploring collaboration ideas related […]<\/p>\n","protected":false},"author":8,"featured_media":0,"parent":3386,"menu_order":6,"comment_status":"closed","ping_status":"closed","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/pages\/4715"}],"collection":[{"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/comments?post=4715"}],"version-history":[{"count":589,"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/pages\/4715\/revisions"}],"predecessor-version":[{"id":9105,"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/pages\/4715\/revisions\/9105"}],"up":[{"embeddable":true,"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/pages\/3386"}],"wp:attachment":[{"href":"https:\/\/l2ep.univ-lille.fr\/en\/wp-json\/wp\/v2\/media?parent=4715"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}