Documents disponibles écrits par cet auteur

Coordinated control approaches for low-voltage ride-through enhancement in wind turbines with doubly fed induction generators / Rahimi, M. in IEEE transactions on energy conversion, Vol. 25, N° 3 (Septembre 2010) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 25, N° 3 (Septembre 2010) . - pp. 873 - 883 Titre : Coordinated control approaches for low-voltage ride-through enhancement in wind turbines with doubly fed induction generators Type de document : texte imprimé Auteurs : Rahimi, M., Auteur ; Parniani, M., Auteur Année de publication : 2011 Article en page(s) : pp. 873 - 883 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : Asynchronous  generators;  overvoltage;  power  convertors;  rotors;  torque  control;  transient  response;  wind  turbines Résumé : This paper deals with the coordinated control of rotor- and grid-side converters in wind turbines with doubly fed induction generators (DFIGs) to improve the low-voltage ride-through capability. The rotor-side converter control and additional equipment, called stator damping resistor, are used to limit the rotor inrush current and to reduce the oscillations and settling time of DFIG transient response during the voltage dip. Also, the grid-side converter is controlled to limit the dc-link overvoltage during the voltage drop. It is found that the dynamics of the grid-side converter and dc-link voltage exhibit nonminimum phase behavior, and thus there is an inherent limitation on the achievable dynamic response during the fault. Since the dc-link dynamics is nonlinear, the linear control scheme cannot properly limit the dc-link voltage under large voltage dips. Thus, a nonlinear control scheme applied to the grid-side converter is proposed, which stabilizes the internal dynamics and limits the dc-link voltage fluctuations during the fault. The proposed ride-through approaches limit the peak values of rotor current and dc-link voltage at the instants of occurring and clearing the fault. They also limit the oscillations of electromagnetic torque, and consequently, improve the DFIG voltage dip behavior. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5552157&sortType%3Das [...] [article] Coordinated control approaches for low-voltage ride-through enhancement in wind turbines with doubly fed induction generators [texte imprimé] / Rahimi, M., Auteur ; Parniani, M., Auteur . - 2011 . - pp. 873 - 883. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 25, N° 3 (Septembre 2010) . - pp. 873 - 883 Mots-clés : Asynchronous  generators;  overvoltage;  power  convertors;  rotors;  torque  control;  transient  response;  wind  turbines Résumé : This paper deals with the coordinated control of rotor- and grid-side converters in wind turbines with doubly fed induction generators (DFIGs) to improve the low-voltage ride-through capability. The rotor-side converter control and additional equipment, called stator damping resistor, are used to limit the rotor inrush current and to reduce the oscillations and settling time of DFIG transient response during the voltage dip. Also, the grid-side converter is controlled to limit the dc-link overvoltage during the voltage drop. It is found that the dynamics of the grid-side converter and dc-link voltage exhibit nonminimum phase behavior, and thus there is an inherent limitation on the achievable dynamic response during the fault. Since the dc-link dynamics is nonlinear, the linear control scheme cannot properly limit the dc-link voltage under large voltage dips. Thus, a nonlinear control scheme applied to the grid-side converter is proposed, which stabilizes the internal dynamics and limits the dc-link voltage fluctuations during the fault. The proposed ride-through approaches limit the peak values of rotor current and dc-link voltage at the instants of occurring and clearing the fault. They also limit the oscillations of electromagnetic torque, and consequently, improve the DFIG voltage dip behavior. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5552157&sortType%3Das [...]

Transient performance improvement of wind turbines with doubly fed induction generators using nonlinear control strategy / Rahimi, M. 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. 514 - 525 Titre : Transient performance improvement of wind turbines with doubly fed induction generators using nonlinear control strategy Type de document : texte imprimé Auteurs : Rahimi, M., Auteur ; Parniani, M., Auteur Année de publication : 2010 Article en page(s) : pp. 514 - 525 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : asynchronous  generators;  machine  control;  nonlinear  control  systems;  transient  analysis;  voltage  control;  wind  turbines Résumé : This paper first discusses dynamic characteristics of wind turbines with doubly fed induction generator (DFIG). Rotor back electromotive force (EMF) voltages in DFIG reflect the effects of stator dynamics on rotor current dynamics, and have an important role on rotor inrush current during the generator voltage dip. Compensation of these voltages can improve DFIG ride-through capability and limit the rotor current transients. It is found that the electrical dynamics of the DFIG are in nonminimum phase for certain operating conditions. Also, it is shown that the dynamics of DFIG, under compensation of rotor back EMF and grid voltages, behave as a partially linearizable system containing internal and external dynamics. The internal and external dynamics of DFIG include stator and rotor dynamics, respectively. It is found that under certain operating conditions, the internal dynamics, and thus, the entire DFIG system becomes unstable. This phenomenon deteriorates the DFIG postfault behavior. Since the DFIG electrical dynamics are nonlinear; the linear control scheme cannot properly work under large voltage dips. We address this problem by means of a nonlinear controller. The proposed approach stabilizes the internal dynamics through rotor voltage control, and improves the dynamic behavior of the DFIG after clearing the fault. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5306105&sortType%3Das [...] [article] Transient performance improvement of wind turbines with doubly fed induction generators using nonlinear control strategy [texte imprimé] / Rahimi, M., Auteur ; Parniani, M., Auteur . - 2010 . - pp. 514 - 525. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 25 N° 2 (Juin 2010) . - pp. 514 - 525 Mots-clés : asynchronous  generators;  machine  control;  nonlinear  control  systems;  transient  analysis;  voltage  control;  wind  turbines Résumé : This paper first discusses dynamic characteristics of wind turbines with doubly fed induction generator (DFIG). Rotor back electromotive force (EMF) voltages in DFIG reflect the effects of stator dynamics on rotor current dynamics, and have an important role on rotor inrush current during the generator voltage dip. Compensation of these voltages can improve DFIG ride-through capability and limit the rotor current transients. It is found that the electrical dynamics of the DFIG are in nonminimum phase for certain operating conditions. Also, it is shown that the dynamics of DFIG, under compensation of rotor back EMF and grid voltages, behave as a partially linearizable system containing internal and external dynamics. The internal and external dynamics of DFIG include stator and rotor dynamics, respectively. It is found that under certain operating conditions, the internal dynamics, and thus, the entire DFIG system becomes unstable. This phenomenon deteriorates the DFIG postfault behavior. Since the DFIG electrical dynamics are nonlinear; the linear control scheme cannot properly work under large voltage dips. We address this problem by means of a nonlinear controller. The proposed approach stabilizes the internal dynamics through rotor voltage control, and improves the dynamic behavior of the DFIG after clearing the fault. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5306105&sortType%3Das [...]