Documents disponibles écrits par cet auteur

Additional losses in the damper winding of large hydrogenerators at open-circuit and load conditions / Traxler-Samek, Georg in IEEE transactions on industrial electronics, Vol. 57 N° 1 (Janvier 2010) 

Public ISBD [article]  in IEEE transactions on industrial electronics > Vol. 57 N° 1 (Janvier 2010) . - pp. 154 - 160 Titre : Additional losses in the damper winding of large hydrogenerators at open-circuit and load conditions Type de document : texte imprimé Auteurs : Traxler-Samek, Georg, Auteur ; Lugand, Thomas, Auteur ; Schwery, Alexander, Auteur Article en page(s) : pp. 154 - 160 Note générale : Génie électrique Langues : Anglais (eng) Mots-clés : AC  generators  AC  machines  Equivalent  circuits  Losses  Machine  windings  Synchronous  generators  Synchronous  machines  Windings Index. décimale : 621.38 Dispositifs électroniques. Tubes à électrons. Photocellules. Accélérateurs de particules. Tubes à rayons X Résumé : Large salient-pole synchronous machines are typically equipped with a damper winding. At steady-state conditions, parasitic voltages are induced in the damper bars which lead to a current flow with associated power losses. This paper describes an analytical algorithm for the calculation of currents and corresponding losses in the damper winding. The presented method is based on an equivalent network of the damper winding containing all the bars of a repetitive section of the machine. The inductances are calculated with an air-gap permeance model. Contrary to similar existing approaches, the induced damper-bar voltages are computed using a numerical integration. This allows more precise results when it comes to higher harmonics. In order to validate the analytical computation, the results are compared with the results of 2-D transient finite-element studies and with a conventional analytical method based on the d-and q -axis equivalent circuits of the machine. DEWEY : 621.38 ISSN : 0278-0046 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5166502 [article] Additional losses in the damper winding of large hydrogenerators at open-circuit and load conditions [texte imprimé] / Traxler-Samek, Georg, Auteur ; Lugand, Thomas, Auteur ; Schwery, Alexander, Auteur . - pp. 154 - 160. Génie électrique Langues : Anglais (eng) in IEEE transactions on industrial electronics > Vol. 57 N° 1 (Janvier 2010) . - pp. 154 - 160 Mots-clés : AC  generators  AC  machines  Equivalent  circuits  Losses  Machine  windings  Synchronous  generators  Synchronous  machines  Windings Index. décimale : 621.38 Dispositifs électroniques. Tubes à électrons. Photocellules. Accélérateurs de particules. Tubes à rayons X Résumé : Large salient-pole synchronous machines are typically equipped with a damper winding. At steady-state conditions, parasitic voltages are induced in the damper bars which lead to a current flow with associated power losses. This paper describes an analytical algorithm for the calculation of currents and corresponding losses in the damper winding. The presented method is based on an equivalent network of the damper winding containing all the bars of a repetitive section of the machine. The inductances are calculated with an air-gap permeance model. Contrary to similar existing approaches, the induced damper-bar voltages are computed using a numerical integration. This allows more precise results when it comes to higher harmonics. In order to validate the analytical computation, the results are compared with the results of 2-D transient finite-element studies and with a conventional analytical method based on the d-and q -axis equivalent circuits of the machine. DEWEY : 621.38 ISSN : 0278-0046 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5166502

Cooling airflow, losses, and temperatures in large air-cooled synchronous machines / Traxler-Samek, Georg in IEEE transactions on industrial electronics, Vol. 57 N° 1 (Janvier 2010) 

Public ISBD [article]  in IEEE transactions on industrial electronics > Vol. 57 N° 1 (Janvier 2010) . - pp. 172 - 180 Titre : Cooling airflow, losses, and temperatures in large air-cooled synchronous machines Type de document : texte imprimé Auteurs : Traxler-Samek, Georg, Auteur ; Zickermann, Richard, Auteur ; Schwery, Alexander, Auteur Article en page(s) : pp. 172 - 180 Note générale : Génie électrique Langues : Anglais (eng) Mots-clés : Cooling  Hydroelectric  generators  Losses  Synchronous  generators  Synchronous  machines  Temperature Index. décimale : 621.38 Dispositifs électroniques. Tubes à électrons. Photocellules. Accélérateurs de particules. Tubes à rayons X Résumé : At steady-state operation, power losses cause a heating of rotating electrical machines. In air-cooled machines, these losses are evacuated by a forced cooling airflow through the active parts. When designing and optimizing such a machine, the design engineer must be able to get a full picture of the power losses, the cooling airflow, and the temperatures inside the active parts (e.g., core laminations, windings) and the periphery (e.g., winding overhangs). The aim of the designer is to fulfill the customer's requirements regarding the guaranteed temperatures. This paper presents a computation method, where the power loss, airflow, and temperature calculations for the world's largest air-cooled hydrogenerators are coupled in an iterative process. The new contribution of this paper is a calculation software developed by the authors. It includes a state-of-the-art loss computation, an automated airflow network, and a set of linked thermal networks. These computations result in a complete overview of the temperature gradients and allow fine tuning of the cooling airflow and, consequently, optimization of ventilation losses. DEWEY : 621.38 ISSN : 0278-0046 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5229207 [article] Cooling airflow, losses, and temperatures in large air-cooled synchronous machines [texte imprimé] / Traxler-Samek, Georg, Auteur ; Zickermann, Richard, Auteur ; Schwery, Alexander, Auteur . - pp. 172 - 180. Génie électrique Langues : Anglais (eng) in IEEE transactions on industrial electronics > Vol. 57 N° 1 (Janvier 2010) . - pp. 172 - 180 Mots-clés : Cooling  Hydroelectric  generators  Losses  Synchronous  generators  Synchronous  machines  Temperature Index. décimale : 621.38 Dispositifs électroniques. Tubes à électrons. Photocellules. Accélérateurs de particules. Tubes à rayons X Résumé : At steady-state operation, power losses cause a heating of rotating electrical machines. In air-cooled machines, these losses are evacuated by a forced cooling airflow through the active parts. When designing and optimizing such a machine, the design engineer must be able to get a full picture of the power losses, the cooling airflow, and the temperatures inside the active parts (e.g., core laminations, windings) and the periphery (e.g., winding overhangs). The aim of the designer is to fulfill the customer's requirements regarding the guaranteed temperatures. This paper presents a computation method, where the power loss, airflow, and temperature calculations for the world's largest air-cooled hydrogenerators are coupled in an iterative process. The new contribution of this paper is a calculation software developed by the authors. It includes a state-of-the-art loss computation, an automated airflow network, and a set of linked thermal networks. These computations result in a complete overview of the temperature gradients and allow fine tuning of the cooling airflow and, consequently, optimization of ventilation losses. DEWEY : 621.38 ISSN : 0278-0046 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5229207