V. Leconte - Academia.edu (original) (raw)
Papers by V. Leconte
Transformers Magazine, Jul 8, 2020
Transformers' windings experience mechanical loads from electromagnetic forces due to the current... more Transformers' windings experience mechanical loads from electromagnetic forces due to the currents they carry. During normal operation, the resulting stresses and strains have minor influence, therefore they do not represent the significant risk to the devices' integrity. However, transformers can suffer from high sudden short-circuit currents that are several times higher than those during the normal operation. These short-circuit currents are a significant threat, not only from an electrical but also from the structural integrity point of view. In this paper, coupled electromagnetic and structural mechanics simulations are carried out to evaluate short-circuit fault risks in a comprehensive and accurate way.
A European consortium consisting of four major steel manufacturers and ten academic technology in... more A European consortium consisting of four major steel manufacturers and ten academic technology institutes has conducted a research and development project, called “Product Uniformity Control“ (PUC) in the period 2013 to 2017. This project aimed to develop and improve non-destructive (inline) measurement techniques to characterise the (uniformity of the) microstructure of steel strip products. In this project, a multitude of strip steel samples from various stages of production have been collected from the four participating steel manufacturers. The samples have been characterised in various ways, namely on their (1) non-destructive measurement parameters using different techniques suited for inline evaluation, (2) fundamental ultrasonic and electromagnetic properties (wave speed, ultrasonic attenuation, magnetisation loops, coercive field), (3) tensile properties (stress-strain curves) and (4) microstructure (by optical micrographs and EBSD images). The correlations between these di...
As mudanças no mundo do trabalho impactam na inserção de homens e mulheres no universo produtivo ... more As mudanças no mundo do trabalho impactam na inserção de homens e mulheres no universo produtivo e reprodutivo o que faz perceber que há uma nítida e tradicional segregação quanto aos postos e condições de trabalho, mostrando, assim, uma desigualdade quanto às relações de gênero no que tange à ocupação dentro do universo do trabalho. Todavia, essa desigualdade não surge com o capitalismo, mas é nele que se intensifica, uma vez que é evidente como o trabalho feminino é satisfatório ao sistema produtivo, principalmente quando visto a naturalização da (in) visibilidade do trabalho reprodutivo, uma vez que não há por parte do Estado a proposição/elaboração de políticas sociais que garantam às mulheres a emancipação do seu lugar como normatizador junto à realização das atividades domésticas. É a partir desse anseio que o presente artigo se propõe a contribuir com o aprofundamento do debate acerca da divisão sócio sexual (e desigual) do trabalho em tempos de contrarreforma do Estado e, ainda, pensando em somar com a categoria dos/as assistentes sociais que é, majoritariamente, composta por mulheres. Como caminho metodológico, se caracteriza como uma pesquisa qualitativa e de cunho bibliográfica, a qual buscou aprofundar-se para que a essência do fenômeno estudado fosse revelada, sendo assim guiada pelo método crítico dialético. Portanto, é perceptível o quanto ainda é necessário o aprofundamento desse debate entre as categorias de gênero e classe (evidenciando a importância das questões de raça/etnia e orientação sexual), uma vez que a classe trabalhadora não é homogênea.
2006 12th Biennial IEEE Conference on Electromagnetic Field Computation
I. INTRODUCTION The equipment manufactured by Schneider Electric, such as circuit breakers, panel... more I. INTRODUCTION The equipment manufactured by Schneider Electric, such as circuit breakers, panelboards and busway systems, have to comply with the requirements of several standards organizations. One of these requirements is the temperature test, which defines ...
IEEE Transactions on Magnetics, 2000
IEEE Transactions on Magnetics, 2006
During the presizing of electromagnetic devices, the designer needs fast calculation tools allowi... more During the presizing of electromagnetic devices, the designer needs fast calculation tools allowing him to make optimizations. Reluctance networks are thus very often used as approximate models: they are easy to interpret and provide very short computing times. However, to set them to equations is a tiresome task and often leads to errors. The paper proposes to automate this task. Starting from a simple and intuitive graphic interface, the model and its partial derivatives are automatically generated. Thus, optimization sizing and sensibility computation can be carried out.
IEEE Transactions on Magnetics, 2015
2006 12th Biennial IEEE Conference on Electromagnetic Field Computation, 2006
ABSTRACT France Transfo noted the breakdown of some of its dry transformers, caused by the destru... more ABSTRACT France Transfo noted the breakdown of some of its dry transformers, caused by the destruction of the high voltage windings. Dielectric constraints in the resin of these windings have been modeled, taking the arrangement errors of the turns into account. The goal is to evaluate which configurations of windings could be critical for the transformer
Journal of Magnetism and Magnetic Materials, 2002
ABSTRACT The numerical tools required by the transient modeling of electrical machines are review... more ABSTRACT The numerical tools required by the transient modeling of electrical machines are reviewed from an energetic viewpoint. The consistency with the finite element method is given. The impact of these modeling requirements is inspected on a high-sensitivity relay case-study and attention on motion-induced eddy currents is given. Due to the trend in energy savings expected in many markets, it is emphasized that future numerical software should take properly into account the loss processes within a 3-dimensional description.
IEEE Transactions on Magnetics, 2002
This paper presents a new finite-element method for including a bulk superconductor in an electri... more This paper presents a new finite-element method for including a bulk superconductor in an electrical circuit. The method solves simultaneously the finite-element equations of formulation and the circuit equations. At the same time, a power law defines the superconducting properties. The method then compares the classical homogeneous model of a Bi-2223 tape to a multifilament model. The results of a simulation of conductors carrying alternative current while subjected to an external ac field are presented.
IEEE Transactions on Magnetics, 2000
This paper presents a magneto-dynamic finite element formulation coupled with circuit equations u... more This paper presents a magneto-dynamic finite element formulation coupled with circuit equations using the time-integrated electric potential. This formulation in high frequency, including displacement currents, permits the study of electric-magnetic interactions in electric coils. The massive conductors in which eddy currents can develop are considered. This formulation can resolve the parasitic capacitive effect problems in massive components for an axi-symmetrical domain.
The European Physical Journal Applied Physics, 2001
Meshless methods are new numerical simulation methods. Meshless methods are based on a simple set... more Meshless methods are new numerical simulation methods. Meshless methods are based on a simple set of nodes that has to be optimized to obtain a good convergence of the approximation. For these reasons, in this paper, we have developed a new procedure in order to generate the initial set of nodes. This approach does not rely on any existing meshing technique, such as Delaunay or advancing front. It is based on a map density of nodes and a regularization procedure.
The European Physical Journal Applied Physics, 2001
When performing the analysis of electromechanical transient problems with movement, it is needed ... more When performing the analysis of electromechanical transient problems with movement, it is needed to take into account the air gap deformation with time. A new remeshing procedure is proposed. It is based on node displacements coupled to a Delaunay algorithm. The node movement is described using bubbles in association with a physical model. The procedure generates high-quality meshes.
This paper presents numerical techniques for the modeling of the transients of an electromechanic... more This paper presents numerical techniques for the modeling of the transients of an electromechanical de- vice. External excitation circuit and rigid body motion as well as electromagnetic phenomena are dealt with. The fo- cus is put on methods for movement consideration in the finite element context. An original technique is shown to cope with the presence of small air-gaps during the move- ment. Some 2D results are presented.
2005 International Conference on Electrical Machines and Systems, 2005
Transformers Magazine, Jul 8, 2020
Transformers' windings experience mechanical loads from electromagnetic forces due to the current... more Transformers' windings experience mechanical loads from electromagnetic forces due to the currents they carry. During normal operation, the resulting stresses and strains have minor influence, therefore they do not represent the significant risk to the devices' integrity. However, transformers can suffer from high sudden short-circuit currents that are several times higher than those during the normal operation. These short-circuit currents are a significant threat, not only from an electrical but also from the structural integrity point of view. In this paper, coupled electromagnetic and structural mechanics simulations are carried out to evaluate short-circuit fault risks in a comprehensive and accurate way.
A European consortium consisting of four major steel manufacturers and ten academic technology in... more A European consortium consisting of four major steel manufacturers and ten academic technology institutes has conducted a research and development project, called “Product Uniformity Control“ (PUC) in the period 2013 to 2017. This project aimed to develop and improve non-destructive (inline) measurement techniques to characterise the (uniformity of the) microstructure of steel strip products. In this project, a multitude of strip steel samples from various stages of production have been collected from the four participating steel manufacturers. The samples have been characterised in various ways, namely on their (1) non-destructive measurement parameters using different techniques suited for inline evaluation, (2) fundamental ultrasonic and electromagnetic properties (wave speed, ultrasonic attenuation, magnetisation loops, coercive field), (3) tensile properties (stress-strain curves) and (4) microstructure (by optical micrographs and EBSD images). The correlations between these di...
As mudanças no mundo do trabalho impactam na inserção de homens e mulheres no universo produtivo ... more As mudanças no mundo do trabalho impactam na inserção de homens e mulheres no universo produtivo e reprodutivo o que faz perceber que há uma nítida e tradicional segregação quanto aos postos e condições de trabalho, mostrando, assim, uma desigualdade quanto às relações de gênero no que tange à ocupação dentro do universo do trabalho. Todavia, essa desigualdade não surge com o capitalismo, mas é nele que se intensifica, uma vez que é evidente como o trabalho feminino é satisfatório ao sistema produtivo, principalmente quando visto a naturalização da (in) visibilidade do trabalho reprodutivo, uma vez que não há por parte do Estado a proposição/elaboração de políticas sociais que garantam às mulheres a emancipação do seu lugar como normatizador junto à realização das atividades domésticas. É a partir desse anseio que o presente artigo se propõe a contribuir com o aprofundamento do debate acerca da divisão sócio sexual (e desigual) do trabalho em tempos de contrarreforma do Estado e, ainda, pensando em somar com a categoria dos/as assistentes sociais que é, majoritariamente, composta por mulheres. Como caminho metodológico, se caracteriza como uma pesquisa qualitativa e de cunho bibliográfica, a qual buscou aprofundar-se para que a essência do fenômeno estudado fosse revelada, sendo assim guiada pelo método crítico dialético. Portanto, é perceptível o quanto ainda é necessário o aprofundamento desse debate entre as categorias de gênero e classe (evidenciando a importância das questões de raça/etnia e orientação sexual), uma vez que a classe trabalhadora não é homogênea.
2006 12th Biennial IEEE Conference on Electromagnetic Field Computation
I. INTRODUCTION The equipment manufactured by Schneider Electric, such as circuit breakers, panel... more I. INTRODUCTION The equipment manufactured by Schneider Electric, such as circuit breakers, panelboards and busway systems, have to comply with the requirements of several standards organizations. One of these requirements is the temperature test, which defines ...
IEEE Transactions on Magnetics, 2000
IEEE Transactions on Magnetics, 2006
During the presizing of electromagnetic devices, the designer needs fast calculation tools allowi... more During the presizing of electromagnetic devices, the designer needs fast calculation tools allowing him to make optimizations. Reluctance networks are thus very often used as approximate models: they are easy to interpret and provide very short computing times. However, to set them to equations is a tiresome task and often leads to errors. The paper proposes to automate this task. Starting from a simple and intuitive graphic interface, the model and its partial derivatives are automatically generated. Thus, optimization sizing and sensibility computation can be carried out.
IEEE Transactions on Magnetics, 2015
2006 12th Biennial IEEE Conference on Electromagnetic Field Computation, 2006
ABSTRACT France Transfo noted the breakdown of some of its dry transformers, caused by the destru... more ABSTRACT France Transfo noted the breakdown of some of its dry transformers, caused by the destruction of the high voltage windings. Dielectric constraints in the resin of these windings have been modeled, taking the arrangement errors of the turns into account. The goal is to evaluate which configurations of windings could be critical for the transformer
Journal of Magnetism and Magnetic Materials, 2002
ABSTRACT The numerical tools required by the transient modeling of electrical machines are review... more ABSTRACT The numerical tools required by the transient modeling of electrical machines are reviewed from an energetic viewpoint. The consistency with the finite element method is given. The impact of these modeling requirements is inspected on a high-sensitivity relay case-study and attention on motion-induced eddy currents is given. Due to the trend in energy savings expected in many markets, it is emphasized that future numerical software should take properly into account the loss processes within a 3-dimensional description.
IEEE Transactions on Magnetics, 2002
This paper presents a new finite-element method for including a bulk superconductor in an electri... more This paper presents a new finite-element method for including a bulk superconductor in an electrical circuit. The method solves simultaneously the finite-element equations of formulation and the circuit equations. At the same time, a power law defines the superconducting properties. The method then compares the classical homogeneous model of a Bi-2223 tape to a multifilament model. The results of a simulation of conductors carrying alternative current while subjected to an external ac field are presented.
IEEE Transactions on Magnetics, 2000
This paper presents a magneto-dynamic finite element formulation coupled with circuit equations u... more This paper presents a magneto-dynamic finite element formulation coupled with circuit equations using the time-integrated electric potential. This formulation in high frequency, including displacement currents, permits the study of electric-magnetic interactions in electric coils. The massive conductors in which eddy currents can develop are considered. This formulation can resolve the parasitic capacitive effect problems in massive components for an axi-symmetrical domain.
The European Physical Journal Applied Physics, 2001
Meshless methods are new numerical simulation methods. Meshless methods are based on a simple set... more Meshless methods are new numerical simulation methods. Meshless methods are based on a simple set of nodes that has to be optimized to obtain a good convergence of the approximation. For these reasons, in this paper, we have developed a new procedure in order to generate the initial set of nodes. This approach does not rely on any existing meshing technique, such as Delaunay or advancing front. It is based on a map density of nodes and a regularization procedure.
The European Physical Journal Applied Physics, 2001
When performing the analysis of electromechanical transient problems with movement, it is needed ... more When performing the analysis of electromechanical transient problems with movement, it is needed to take into account the air gap deformation with time. A new remeshing procedure is proposed. It is based on node displacements coupled to a Delaunay algorithm. The node movement is described using bubbles in association with a physical model. The procedure generates high-quality meshes.
This paper presents numerical techniques for the modeling of the transients of an electromechanic... more This paper presents numerical techniques for the modeling of the transients of an electromechanical de- vice. External excitation circuit and rigid body motion as well as electromagnetic phenomena are dealt with. The fo- cus is put on methods for movement consideration in the finite element context. An original technique is shown to cope with the presence of small air-gaps during the move- ment. Some 2D results are presented.
2005 International Conference on Electrical Machines and Systems, 2005