Documents disponibles écrits par cet auteur

A field reconstruction technique for efficient modeling of the fields and forces within induction machines / Dezheng, Wu in IEEE transactions on energy conversion, Vol. 24 N° 2 (Juin 2009) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 24 N° 2 (Juin 2009) . - pp. 366 - 374 Titre : A field reconstruction technique for efficient modeling of the fields and forces within induction machines Type de document : texte imprimé Auteurs : Dezheng, Wu, Auteur ; Pekarek, S.D., Auteur ; Fahimi, B., Auteur Année de publication : 2009 Article en page(s) : pp. 366 - 374 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous  machines;  computational  complexity;  finite  element  analysis Résumé : Traditional analysis and design of induction machines have been largely based upon lumped-parameter models. An alternative tool used for field-based evaluations of an induction machine is the finite-element method. Although useful, its computational complexity limits its use as a design tool. In this paper, a field reconstruction (FR) method for induction machine simulation is introduced. The FR method utilizes a small number of finite-element evaluations to establish basis functions of normal and tangential flux densities. The basis functions are then used to estimate the magnetic field under arbitrary stator excitation. Using such a tool, evaluation of fields and forces produced by a machine under alternative excitation strategies can be explored efficiently. Moreover, alternative field-based derivation of stator/rotor excitation control can be explored. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4957569&sortType%3Das [...] [article] A field reconstruction technique for efficient modeling of the fields and forces within induction machines [texte imprimé] / Dezheng, Wu, Auteur ; Pekarek, S.D., Auteur ; Fahimi, B., Auteur . - 2009 . - pp. 366 - 374. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 24 N° 2 (Juin 2009) . - pp. 366 - 374 Mots-clés : Asynchronous  machines;  computational  complexity;  finite  element  analysis Résumé : Traditional analysis and design of induction machines have been largely based upon lumped-parameter models. An alternative tool used for field-based evaluations of an induction machine is the finite-element method. Although useful, its computational complexity limits its use as a design tool. In this paper, a field reconstruction (FR) method for induction machine simulation is introduced. The FR method utilizes a small number of finite-element evaluations to establish basis functions of normal and tangential flux densities. The basis functions are then used to estimate the magnetic field under arbitrary stator excitation. Using such a tool, evaluation of fields and forces produced by a machine under alternative excitation strategies can be explored efficiently. Moreover, alternative field-based derivation of stator/rotor excitation control can be explored. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4957569&sortType%3Das [...]

Incorporating motion in mesh-based magnetic equivalent circuits / Bash, M. L. in IEEE transactions on energy conversion, Vol. 25 N° 2 (Juin 2010) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 25 N° 2 (Juin 2010) . - pp. 329 - 338 Titre : Incorporating motion in mesh-based magnetic equivalent circuits Type de document : texte imprimé Auteurs : Bash, M. L., Auteur ; Williams, J.M., Auteur ; Pekarek, S.D., Auteur Année de publication : 2010 Article en page(s) : pp. 329 - 338 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : air  gaps;  electric  machines;  equivalent  circuits;  magnetic  circuits;  mesh  generation;  rotors;  synchronous  machines Résumé : Recent research has compared the numerical efficiency of magnetic equivalent circuit (MEC) models based upon Kirchhoff's voltage law (mesh equations) and Kirchhoff's current law (nodal equations). For stationary magnetic components, it was shown that mesh-based methods converge in significantly fewer iterations. Although the numerical advantages would seemingly apply to electric machines, two issues have limited the application of mesh-based MEC models to electric machines. With movement, the number of meshes (unlike the number of nodes) is position dependent. Additionally, the loss of an airgap element creates an infinite reluctance. In this paper, both issues are addressed. Specifically, it is first shown that a relatively straightforward algorithm can be used to dynamically update meshes with rotor position. In addition, it is shown that the mesh model remains stable for very large values of tube reluctance. Tube reluctance values that are large enough to cause numerical issues can be easily avoided by excluding a very narrow range of rotor positions. Based upon these results, a mesh-based MEC model of a wound-rotor synchronous machine is developed and is shown to provide a significant advantage over its nodal-based model equivalent. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5378586&sortType%3Das [...] [article] Incorporating motion in mesh-based magnetic equivalent circuits [texte imprimé] / Bash, M. L., Auteur ; Williams, J.M., Auteur ; Pekarek, S.D., Auteur . - 2010 . - pp. 329 - 338. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 25 N° 2 (Juin 2010) . - pp. 329 - 338 Mots-clés : air  gaps;  electric  machines;  equivalent  circuits;  magnetic  circuits;  mesh  generation;  rotors;  synchronous  machines Résumé : Recent research has compared the numerical efficiency of magnetic equivalent circuit (MEC) models based upon Kirchhoff's voltage law (mesh equations) and Kirchhoff's current law (nodal equations). For stationary magnetic components, it was shown that mesh-based methods converge in significantly fewer iterations. Although the numerical advantages would seemingly apply to electric machines, two issues have limited the application of mesh-based MEC models to electric machines. With movement, the number of meshes (unlike the number of nodes) is position dependent. Additionally, the loss of an airgap element creates an infinite reluctance. In this paper, both issues are addressed. Specifically, it is first shown that a relatively straightforward algorithm can be used to dynamically update meshes with rotor position. In addition, it is shown that the mesh model remains stable for very large values of tube reluctance. Tube reluctance values that are large enough to cause numerical issues can be easily avoided by excluding a very narrow range of rotor positions. Based upon these results, a mesh-based MEC model of a wound-rotor synchronous machine is developed and is shown to provide a significant advantage over its nodal-based model equivalent. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5378586&sortType%3Das [...]

Modeling of induction machines using a voltage-behind-reactance formulation / Liwei, Wang in IEEE transactions on energy conversion, Vol. 23 n°2 (Juin 2008) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 382 - 392 Titre : Modeling of induction machines using a voltage-behind-reactance formulation Type de document : texte imprimé Auteurs : Liwei, Wang, Auteur ; Jatskevich, J., Auteur ; Pekarek, S.D., Auteur Année de publication : 2008 Article en page(s) : pp. 382 - 392 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous  machines;  power  convertors;  power  electronics Résumé : Over the past several years, there has been renewed interest in modeling electrical machines using phase (abc) variables. This paper considers modeling induction machines using phase variables in a voltage-behind-reactance (VBR) formulation. Specifically, three VBR models are proposed wherein the rotor electrical subsystem is modeled using flux linkages as state variables expressed in the qd reference frame. The stator electrical dynamics are represented in abc phase coordinates that enable direct interface of the machine model to an external network. Such a direct interface is advantageous when the machine is fed from a power electronic converter and/or when the modeling is carried out using circuit-based simulators. Computer studies of an induction machine demonstrate that the proposed VBR models achieve a 740% improvement in computational efficiency as compared with the traditional coupled-circuit phase-domain model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505399&sortType%3Das [...] [article] Modeling of induction machines using a voltage-behind-reactance formulation [texte imprimé] / Liwei, Wang, Auteur ; Jatskevich, J., Auteur ; Pekarek, S.D., Auteur . - 2008 . - pp. 382 - 392. Energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 23 n°2 (Juin 2008) . - pp. 382 - 392 Mots-clés : Asynchronous  machines;  power  convertors;  power  electronics Résumé : Over the past several years, there has been renewed interest in modeling electrical machines using phase (abc) variables. This paper considers modeling induction machines using phase variables in a voltage-behind-reactance (VBR) formulation. Specifically, three VBR models are proposed wherein the rotor electrical subsystem is modeled using flux linkages as state variables expressed in the qd reference frame. The stator electrical dynamics are represented in abc phase coordinates that enable direct interface of the machine model to an external network. Such a direct interface is advantageous when the machine is fed from a power electronic converter and/or when the modeling is carried out using circuit-based simulators. Computer studies of an induction machine demonstrate that the proposed VBR models achieve a 740% improvement in computational efficiency as compared with the traditional coupled-circuit phase-domain model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4505399&sortType%3Das [...]

A multirate field construction technique for efficient modeling of the fields and forces within inverter-fed induction machines / Dezheng, Wu in IEEE transactions on energy conversion, Vol. 25 N° 1 (Mars 2010) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 25 N° 1 (Mars 2010) . - pp. 217 - 227 Titre : A multirate field construction technique for efficient modeling of the fields and forces within inverter-fed induction machines Type de document : texte imprimé Auteurs : Dezheng, Wu, Auteur ; Pekarek, S.D., Auteur Année de publication : 2010 Article en page(s) : pp. 217 - 227 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : air  gaps;  asynchronous  machines;  finite  element  analysis;  invertors;  power  convertors;  power  electronics Résumé : In recent research, a field construction technique (FCT) was derived to enable more efficient evaluation of the magnetic fields and forces within induction machines. Using the FCT, the results of two finite-element (FE) solutions are used to establish basis functions for the flux densities in the airgap of the machine. The basis functions are then used to predict the magnetic fields and forces under arbitrary stator excitation. In this paper, a multirate FCT (MRFCT) is proposed to enable efficient FCT modeling of machines that are connected to power electronic converters. Within the MRFCT, the low- and high-frequency components of the stator current are partitioned. The partitioned currents are then used to calculate the flux density and forces at time steps commensurate with the respective low- and high-frequency dynamics. It is shown that applying the MRFCT, the forces and fields of a machine connected to a power electronic circuit can be obtained at a small fraction of the time required for a coupled FE/circuit model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5350668&sortType%3Das [...] [article] A multirate field construction technique for efficient modeling of the fields and forces within inverter-fed induction machines [texte imprimé] / Dezheng, Wu, Auteur ; Pekarek, S.D., Auteur . - 2010 . - pp. 217 - 227. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 25 N° 1 (Mars 2010) . - pp. 217 - 227 Mots-clés : air  gaps;  asynchronous  machines;  finite  element  analysis;  invertors;  power  convertors;  power  electronics Résumé : In recent research, a field construction technique (FCT) was derived to enable more efficient evaluation of the magnetic fields and forces within induction machines. Using the FCT, the results of two finite-element (FE) solutions are used to establish basis functions for the flux densities in the airgap of the machine. The basis functions are then used to predict the magnetic fields and forces under arbitrary stator excitation. In this paper, a multirate FCT (MRFCT) is proposed to enable efficient FCT modeling of machines that are connected to power electronic converters. Within the MRFCT, the low- and high-frequency components of the stator current are partitioned. The partitioned currents are then used to calculate the flux density and forces at time steps commensurate with the respective low- and high-frequency dynamics. It is shown that applying the MRFCT, the forces and fields of a machine connected to a power electronic circuit can be obtained at a small fraction of the time required for a coupled FE/circuit model. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5350668&sortType%3Das [...]

Numerical validation of parametric average-value modeling of synchronous machine–rectifier systems for variable frequency operation / Jatskevich, J. in IEEE transactions on energy conversion, Vol. 23 N°1 (Mars 2008) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 23 N°1 (Mars 2008) . - pp. 342 - 344 Titre : Numerical validation of parametric average-value modeling of synchronous machine–rectifier systems for variable frequency operation Type de document : texte imprimé Auteurs : Jatskevich, J., Auteur ; Pekarek, S.D., Auteur Année de publication : 2008 Article en page(s) : pp. 342 - 344 Note générale : Energy conversion Langues : Anglais (eng) Mots-clés : Nonlinear  functions;  rectifiers;  synchronous  machines Résumé : The derivation of accurate dynamic average-value models for synchronous machine-rectifier systems is challenging. A recently proposed parametric approach uses a computer-aided procedure for constructing the required averaged models, wherein the key nonlinear functions are extracted from a detailed (valve-by-valve) simulation. This letter shows that by using a judicious selection of parametric functions, a model obtained at a fixed generator speed is also valid for variable speeds. This is an important feature that makes this approach applicable to systems where electromechanical dynamics and variable speed operation is required. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4453986&sortType%3Das [...] [article] Numerical validation of parametric average-value modeling of synchronous machine–rectifier systems for variable frequency operation [texte imprimé] / Jatskevich, J., Auteur ; Pekarek, S.D., Auteur . - 2008 . - pp. 342 - 344. Energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 23 N°1 (Mars 2008) . - pp. 342 - 344 Mots-clés : Nonlinear  functions;  rectifiers;  synchronous  machines Résumé : The derivation of accurate dynamic average-value models for synchronous machine-rectifier systems is challenging. A recently proposed parametric approach uses a computer-aided procedure for constructing the required averaged models, wherein the key nonlinear functions are extracted from a detailed (valve-by-valve) simulation. This letter shows that by using a judicious selection of parametric functions, a model obtained at a fixed generator speed is also valid for variable speeds. This is an important feature that makes this approach applicable to systems where electromechanical dynamics and variable speed operation is required. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4453986&sortType%3Das [...]