Afef Kedous-Lebouc

French National Centre for Scientific Research | CNRS · Grenoble Electrical Engineering Laboratory G2Elab

This paper proposes a vector extension of the Loss Surface model for numerically modelling hysteretic phenomena in electromagnetic device simulations with isotropic ferromagnetic materials. The vectorization strategy is based on Mayergoyz’s approach. The developed model has been implemented in the 2D finite element code. To handle the non linear pr...

This paper presents a new calculation of the dynamic part of the Loss Surface (LS) model to consider the magnetization history. It is to be combined with a static model of hysteresis to estimate iron loss. The analysis of the behavior of various hysteresis loops highlighted the history dependency of the dynamic part of the LS model. An innovative f...

The Loss-Surface (LS) model, commonly used for the prediction of iron losses in electrical machines, is reformulated for better accuracy and reliability when it is extrapolated beyond the parametric identification region. First, the dynamic hysteresis behaviors of typical soft magnetic materials are analyzed by both measurements and FE simulations....

Over the last two decades, the research activities on magnetocalorics have been exponentially increased leading to the discovery of a wide category of materials including intermetallics and oxides. Even though the reported materials were found to show excellent magnetocaloric properties on laboratory scale, only a restricted family among them could...

this abstract outlines a multi-physical modeling approach, which has been developed and incorporated in an optimization process. This approach allows the conceptual design of an electrical motor for electric hybrid vehicle. It is elaborated to be malleable and to satisfy different precision levels in order to address various sizing problems.

This article analyzes and highlights the impact of an iron loss model on temperature estimation within a multi-physical model of a radial-flux permanent-magnet (PM) synchronous machine (PMSM) for traction application. Three iron loss models have been compared in terms of computing time and accuracy within the machine torque-speed plane. This study...

This paper presents an evolution of the inverse Play model to reconstruct static hysteresis from a flux density waveform input. It is to be combined with dynamic and 2D or 3D models to estimate complete iron loss in electrical machines. In the first part of the article, the paper shows the significant improvement on the original inverse Play model...

The aeronautics transport is continuously growing. Forecast shows that the number of flights will have doubled by 2037 reaching 8.2 billion of air travelers, with China and India as the main and fastest-growing markets. Urban mobility will be revolutionized and transformed by new aircraft concepts for commuting and delivering services replacing car...

Hysteresis models allow the prediction of iron losses in materials under complex magnetic excitation, with accuracy depending on their principle and identification procedure. Commonly, to achieve high accuracy, a model may require a broad set of experimental input data, which is in some cases, not easy to obtain. We propose, in this study, a static...

The paper deals with the application of the artificial bee colony (ABC) method for hysteresis parameters identification. For the first time, the ABC method will be applied on hysteresis model optimization. For this purpose, two hysteresis models are tested: the first is based on a physical magnetic material behavior, which is Jiles-Atherton and the...

In this paper, we mainly focus on the magnetic and magnetocaloric features of La2-xDyxNiMnO6 double perovskites. Their magnetocaloric properties are investigated in terms of both entropy and adiabatic temperature changes. In contrast to early works, it was found that the Dy2NiMnO6 compound unveils dominant antiferromagnetic interactions under very...

In the context of the ever-expanding application of soft magnetic materials, the fully controlled magnetic measurement has, therefore, become essential. It ensures not only the accurate modeling of materials but also the rigorous quality control throughout the manufacturing process, as well as the explicit communication of magnetic data in academic...

In this paper, we mainly focus on the magnetic and magnetocaloric features of La2−xDyxNiMnO6 double perovskites. Their magnetocaloric properties are investigated in terms of both entropy and adiabatic temperature changes. In contrast to early works, it was found that the Dy2NiMnO6 compound unveils dominant antiferromagnetic interactions under very...

The global supply of heavy rare earth magnets can become risky with the soaring demand of rare earth permanent magnet (PM) machines. One of the promising solutions is to reuse or recycle permanent magnets from end-of-Life electrical machines. This paper is an overview study of the state-of-the-art permanent magnet reuse and recycling research for e...

In this paper, the potential of thin sheet SiFe NO20 and nanocrystalline materials for the realization of the magnetic circuit of high-speed machines is analyzed in a complete procedure. Firstly, intrinsic properties of materials are precisely characterized. Next, the original and a modified model of Bertotti are applied for the modeling of power l...

In this paper, the magnetic losses of a supply current sensor dedicated to circuit breakers are investigated. Measurements were performed using an accurate calorimeter covering a measurement range of [1 mW; 10 W]. Several frequencies and voltages were tested. A model of the sensor's core material (NO SiFe sheet M250-50A) was built with the Loss Sur...

Volatile prices and severe supply-demand issues have led to the development of a significant research area in terms of reuse and recycle of rare earth permanent magnets. Another reason for the proliferation of this research is the increased emphasis on environmental impacts of rare earth material mining which can be substantially reduced by reuse a...

Nowadays, in automotive applications, the electric vehicle motors generally utilize permanent magnet motors due to their various advantages like high torque density, high efficiency, compactness and ease of control. In this paper emphasis is given to the evaluation of energy cost index for an EV motor over a particular drive cycle during motors ope...

With increasing demand of electric vehicles it is very important to recycle critical rare earth materials used in the permanent magnet motors such as Neodymium (Nd), Dysprosium (Dy) and Cobalt (Co) etc. To achieve easy recycling, focus of the motor design shall shift to design for recycling. The article presents a methodology (WIRE) to evaluate and...

This paper presents the influence of variation in various geometric parameters of claw-pole topology on the performance of machine used in automotive application. Due to three-dimensional flux distribution in the claw-pole topology, variation in geometric parameters of the claw-poles results into change in performance of the machine. The geometric...

In the multi-physic and optimal design context of electrical machines, an original and accurate methodology is proposed and applied to a radial-flux interior permanent-magnet synchronous machine (PMSM) dedicated to automotive applications. This approach is based on an iterative coupling between a generalized nonlinear adaptive magnetic equivalent c...

Over the last two decades, the research activities on magnetocalorics have been exponentially increased, leading to the discovery of a wide category of materials including intermetallics and oxides. Even though the reported materials were found to show excellent magnetocaloric properties on a laboratory scale, only a restricted family among them co...

This paper presents the design and performance comparison of a conventional claw-pole machine with a permanent magnet based claw-pole machine for automotive application. The magnets are placed in the inter-claw region to decrease the leakage flux and to supply increased magnetic flux in the machine. It has been observed that with the addition of pe...

Over the last decade, lots of research works showed that ferrofluids could have great interests in thermal systems. However, convective heat transfer coefficient and pressure drop in such systems are very sensitive to many physico-chemical and geometrical parameters which must be well adjusted. In this paper, several key parameters are studied in t...

This paper presents a novel digital control strategy successfully implemented for a soft magnetic material characterization bench (Epstein frame type). The main objective is to control the magnetic induction waveform whatever the applied excitation and the material under study. Given the nonlinear nature of the magnetization curves of magnetic mate...

Mechanical punching of electrical steels causes a degradation of their magnetic characteristics which can extend several millimeters from the cut edge. So, in the field of industrial applications, particularly that of small electrical machines, the stator core made of rigid and thin teeth would be subject to more losses. Thus, this topic of the eff...

In this paper, an original approach allowing the determination of the iron losses in the electromagnetic devices is presented. This new approach exploits the Loss Surface (LS) hysteresis model and the magnetic flux density waveforms resulting from a generalized nonlinear adaptive magnetic equivalent circuit (MEC) using a mesh-based formulation in t...

The representation of a magnetic material using the Preisach Model of hysteresis requires the determination of the Everett function through the measurement of a complete set of B-H curves. Unfortunately, this data is not available in the literature for most materials, which can be a limitation for practical engineering applications. In this paper,...

High performance electrical machines and devices are more and more required to address economical, energy saving and environmental issues. This is particularly important in on-board applications such those used in the automotive industry and aircraft transportation sector. It can be achieved thanks to a rational use of the magnetic materials and th...

In this work, two methods for digital controlling the waveforms of a magnetic characterization setup are proposed. The first one (Method 1) is an original method based on the model-free controller [1] and the second one (Method 2) is based on the electric equivalent circuit (EEC) of the Epstein frame. The performances of these methods are compared...

In this work, two methods for digital controlling the waveforms of a magnetic characterization setup are proposed. The first one (Method 1) is an original method based on the model-free controller [1] and the second one (Method 2) is based on the electric equivalent circuit (EEC) of the Epstein frame. The performances of these methods are compared...

Dans cet article, nous présentons une stratégie innovante d’asservissement numérique destinée à piloter un banc de caractérisation de matériaux magnétiques doux de type cadre Epstein. L’objectif est d’imposer la forme de l’induction magnétique quelle que soit l’excitation et le matériau. Compte- tenu du caractère non-linéaire des courbes d’aimantat...

Dans cet article, nous présentons une approche inédite permettant l’évaluation des pertes magnétiques à partir des formes d’ondes des inductions issues d’un circuit magnétique équivalent (CME) adaptatif non-linéaire par le modèle Loss Surface (LS). L’approche a été appliquée à une machine synchrone à flux radial et à aimants enterrés. Les résultats...

Dans cet article, nous présentons une approche inédite permettant l’évaluation des pertes magnétiques à partir des formes d’ondes des inductions issues d’un circuit magnétique équivalent (CME) adaptatif non-linéaire par le modèle Loss Surface (LS). L’approche a été appliquée à une machine synchrone à flux radial et à aimants enterrés. Les résultats...

In this paper, optimization of the control of an electrical machine allowing a minimization of its total losses is described. It is based on the use of an iron loss model [loss surface (LS) model] coupled to the electromagnetic finite-element simulations of the machine. The LS model is a scalar and dynamic hysteresis model developed many years ago...

Applying a magnetic field on a ferrofluid flow induces a large increase of the convective heat transfer coefficient. In this paper, the thermal-hydraulic behaviors of two commercial ferrofluids are compared. The variations of both the pressure drop and the heat transfer coefficient due to the magnetic field are measured in the following conditions:...

Magnetic refrigeration, based on magnetocaloric effect, is an upcoming environmentaly friendly technology with a high potential to improve energy efficiency and to reduce greenhouse gas emission. It is a multidisciplinary research theme and its real emergence requires, to overcome scientific and technical issues related to both material and system....

Une stratégie innovante d’asservissement numérique destinée à piloter un banc de caractérisation de matériaux magnétiques doux de type cadre Epstein est présentée. L’objectif est d’imposer la forme de l’induction magnétique quelle que soit l’excitation et le matériau. Compte tenu du caractère non-linéaire des courbes d’aimantation des matériaux mag...

Ferrofluids have a highly nonlinear magnetic behavior. Moreover, their colloidal nature may, in certain circumstances, make anisotropic by forming chains. A fine characterization of these liquids is essential. However, conventional measurement methods, setting in motion the samples tested are ineffective against these materials. The following artic...

CISTEM : Conférence Internationale en Sciences et Technologies Electriques au Maghreb

This paper presents an experimental investigation on forced convective heat transfers in a ferrofluid with the presence of a magnetic field. The duct is square, the flow is laminar and the wall heat flux is uniform. The effects of the direction of the magnetic field and of the thermal entrance region are studied. The results show that a better enha...

p>Dans cet article, un magnétomètre original dédié à la caractérisation statique d'un échantillon est proposé. Il est spécialement conçu pour les ferrofluides dont les comportements sont sensibles au champ magnétique et pour lesquels les méthodes classiques utilisant un échantillon mobile ne sont plus adaptées. Le magnétomètre peut également être u...

p>La réfrigération magnétique, basée sur l'effet magnétocalorique, est une thématique relativement récente et prometteuse devant permettre de réaliser des systèmes moins énergivores que la technologie conventionnelle et sans impact sur l'environnement. Pluridisciplinaire, elle implique de maîtriser toute une filière, du matériau à l'application et...

p>Le refroidissement par convection forcée des composants électroniques de puissance, bien que très efficace, nécessite généralement l'utilisation d'une pompe mécanique réduisant le rendement global du système et sa fiabilité. Il a déjà été montré, que l'utilisation des ferrofluides à basse température de Curie produisait un écoulement de ce dernie...

p>Cet article présente une investigation expérimentale de l'étude du transfert de chaleur au sein d'un ferrofluide en convection forcée à flux thermique imposé sous champ magnétique. Le régime d'écoulement étudié est essentiellement laminaire (250 < Re <830). La géométrie du canal de test est carrée, ce qui nous permet d'étudier l'influence de la d...

Pierre Brissonneau passed away on August 4, 2013 at the age of 86. Pierre was born in Saint Agnant Les Marais, France, on April 19, 1927. A physicist and disciple of Louis Néel, he was a Professor at Grenoble Institute of Technology (formerly INPG) and an internationally famous researcher at LEG [today Grenoble Electrical Engineering Laboratory (G2...

In this paper, an original magnetometer dedicated to static sample characterization is proposed. It is especially designed for ferrofluids whose behaviors are sensitive to the magnetic field and for which the classic methods using a mobile sample are no more suitable. The magnetometer can also be used to test any feebly permeability material. The p...

To optimize the performance of an active magnetic regenerative system (AMR), it is important to understand the heat transfer phenomena taking place in the regenerator and the impact of the intrinsic properties of the magnetocaloric material. With this aim in mind, four regenerators involving three different materials (Pr0.65Sr0.35MnO3, La(FeCo)13-x...

In this paper, computational algorithms of different multiobjective optimization techniques and their application for AMR systems are presented. In order to illustrate the effectiveness of the proposed methods, they have been demonstrated on a layered AMR bed, where four objective functions are considered, namely: the temperature span, the cooling...

Liquid cooling of electronic devices requires generally a mechanical pump which reduces the performance of the system and its reliability. It has already been shown that ferrofluids with low Curie temperature are able to create a liquid flow without any mechanical part. In fact a pressure gradient can be obtained when subjecting this ferrofluids to...

Thermal management became a limiting factor in the development of high-power electronic devices, and new methods of cooling are required. Therefore, the use of liquid gallium alloys, whose thermal conductivity (approximately 28 W/m/K) is 40 times greater than thermal conductivity of water, is introduced. In the first part of this paper, we present...

This paper describes a method to study the electrical steels with regard to their application. This methodology attempts to link the design of the electrical machine with the practical magnetic material behavior thanks to visualization tools. Firstly, some magnetic characterization are presented to determine the electrical steel behavior and to val...

In electric vehicles, a major emphasis is placed on iron loss reduction to maximize machine efficiency and its vibratory and acoustic behavior to meet users' expectations of a silent drive. This paper describes a method to simultaneously reduce iron losses and magnetic noise of a wound-field synchronous machine considering various stator tooth leng...

This paper presents the improvement of an iron loss model. This model meets the requirements of iron loss modeling in electrical machine by rebuilding the hysteresis cycle. Various magnetic flux density waveforms have been measured on Epstein frame to validate the model. The model shows good accuracy with measurements. It is then applied to an elec...

Testing directly a magnetocaloric material in a magnetic refrigeration (MR) system is the best way to judge of its applicative potentialities. In this spirit, an oxide expected to show promising magnetocaloric properties around room temperature (Pr0.65Sr0.35MnO3) was produced in large scale and shaped in order to build a regenerator. Magnetization,...

Magnetic refrigeration (MR) based on the magnetocaloric effect (MCE) is a prime candidate for the next generation of cooling systems. The essential components of magnetic refrigeration are the magnetic field generator and the magnetocaloric material. Although, several permanent magnet systems (magnetic field sources) for MR have been developed, rec...

A one-dimensional transient model of an active magnetic regenerator has been developed. The magnetocaloric properties are calculated using the Mean field theory and the model is used to study the transient and steady state response of a parallel plate regenerator. A parametric study is performed and highlights the influence of the Number of Transfe...

The need to adopt new cooling techniques arouse because of the continuous increase in power dissipation of electronic parts and systems. Due to the low thermal conductivity of classical liquids (water, alcohols, dielectric fluids...), in many cases, the standard liquid cooling techniques cannot achieve the required cooling performances. This paper...

Thermal management became the limiting factor in the development of high power electronic devices and new methods of cooling are required. Due to the low thermal conductivity of classical liquids (water, alcohols, dielectric fluids…), in many cases, the standard liquid cooling techniques cannot achieve the required cooling performances. Therefore t...

Fast switching in power converters generate large amount of ElectroMagnetic Interference (EMI). Two modes of conducted EMI noise: Differential (DM) and Common Mode (CM) are identified. Traditional EMI filters are made up of two magnetic components, used to reduce each noise. Standards impose attenuation in a large frequency range (10 kHz to 100 MHz...

Power electronic designers are interested in characterization of the magnetic cores permeability up to 10MHz and at high induction level. To achieve this aim, different experimental setups are used to measure mutual impedance spectra. First, impedance measurement methods are carried out on toroidal wound core of 20 μm nanocrystalline ribbons. Measu...