INVESTIGATION OF THE CROSS-MAGNETIZING PHENOMENON IN SATURATED SYNCHRONOUS MACHINES APPLYING THE FINITE ELEMENT METHOD
Notice bibliographique
Résumé
It has been recognized recently that the magnetic coupling between the direct and quadrature axes of saturated synchronous machines(the cross-magnetizing phenomenon) plays an important role in their analysis. This phenomenon results in the reduction in the magnitudes of the direct- and quadrature-axis magnetic fluxes from their corresponding magnitudes. The fundamental components of the induced electromotive forces corresponding to these reductions in the magnetic fluxes could be used as the parameters representing the cross-magnetizing phenomenon. To calculate these parameters, the two-dimensional finite element method is applied to determine the parameters from the static electromagnetic field solutions. A specially designed synchronous machine that can be excited from both its direct and quadrature axes is used in the investigations in order that the parameters representing the cross-magnetizing effect could be measured experimentally and, thus, the accuracy of the solutions using the finite element method can be verified.\n\nIn order to obtain these parameters, the saturation characteristics of the machine in the direct, quadrature and various intermediate axes are needed. The calculations of these characteristics using the finite element method are carried out on both the central line of the air gap and the inner surface of the stator of synchronous machines for three different relative positions between the stator and rotor. Four models with different air-gap lengths have been considered in the investigations. These calculations indicate that their accuracy are not practically affected by performing the calculation on the central line of the air gap or on the inner surface of the stator and, thus, both cases can be used without affecting the accuracy. With regards to the relative positions between the stator and rotor, there are only very slight discrepancies between the calculated results for the various relative positions considered and practically the relative positions have no effect on the accuracy of the calculations. Thus, the calculations can be carried out at any relative positions. Moreover, the knowledge of the accurate values of the air-gap length\n11of the synchronous machines is essential to obtain accurate results for the saturation characteristics of the synchronous machines. Since such accurate values are usually not available, the d-axis saturation characteristics calculated by the finite element method can be used to obtain accurate estimations of the air-gap length by fitting these calculated results with the measurable d-axis open-circuit characteristics. The accuracy of the calculation of the saturation characteristics has been verified by comparing them with the measured open-circuit characteristics of the specially designed synchronous machine.\n\nWith regards to the cross-magnetizing phenomenon, the results of the investigations carried out in the thesis have confirmed its existence and have shown that the calculated parameters representing this phenomenon using the finite element method are in a\nreasonable agreement with the measured values. This lends credence to the use of the finite element method for predicting these parameters.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,001 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,001 |
| Science ouverte | 0,001 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».