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New constant electrical power soft-stalling control for small-scale VAWTs / Ahmed, Ashraf in IEEE transactions on energy conversion, Vol. 25, N° 4 (Décembre 2010) 

Public ISBD [article]  in IEEE transactions on energy conversion > Vol. 25, N° 4 (Décembre 2010) . - pp. 1152 - 1161 Titre : New constant electrical power soft-stalling control for small-scale VAWTs Type de document : texte imprimé Auteurs : Ahmed, Ashraf, Auteur ; Ran, L., Auteur ; Bumby, J. R., Auteur Année de publication : 2011 Article en page(s) : pp. 1152 - 1161 Note générale : energy conversion Langues : Anglais (eng) Mots-clés : Adaptive  control;  electric  current  control;  feedback;  nonlinear  control  systems;  permanent  magnet  generators;  position  control;  power  control;  synchronous  generators;  wind  turbines Résumé : This paper presents a constant power soft-stall control scheme for a vertical-axis wind turbine (VAWT) fitted with a permanent magnet generator. Small-scale VAWTs are attractive due to their ability to capture wind from different directions without using yaw; this simplifies the design and gives the turbine tolerance to turbulence in urban areas. One difficulty with VAWTs is to prevent overspeeding and component overloading at excessive wind velocities. This paper suggests that necessary control can be achieved by controlling the electric power in order to operate the turbine in the stall region. This control strategy attenuates the stress in the system, while smoothing the power generated. It is shown that the controller can stabilize the nonlinear system using an adaptive current feedback loop. The controller does not need wind velocity or turbine speed, but is based on the current and voltage measured on the dc side of the rectifier connected to the permanent magnet synchronous generator. Maximum power point tracking (MPPT) control is provided in normal operation. Simulation and experimental results are presented. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5444990&sortType%3Das [...] [article] New constant electrical power soft-stalling control for small-scale VAWTs [texte imprimé] / Ahmed, Ashraf, Auteur ; Ran, L., Auteur ; Bumby, J. R., Auteur . - 2011 . - pp. 1152 - 1161. energy conversion Langues : Anglais (eng) in IEEE transactions on energy conversion > Vol. 25, N° 4 (Décembre 2010) . - pp. 1152 - 1161 Mots-clés : Adaptive  control;  electric  current  control;  feedback;  nonlinear  control  systems;  permanent  magnet  generators;  position  control;  power  control;  synchronous  generators;  wind  turbines Résumé : This paper presents a constant power soft-stall control scheme for a vertical-axis wind turbine (VAWT) fitted with a permanent magnet generator. Small-scale VAWTs are attractive due to their ability to capture wind from different directions without using yaw; this simplifies the design and gives the turbine tolerance to turbulence in urban areas. One difficulty with VAWTs is to prevent overspeeding and component overloading at excessive wind velocities. This paper suggests that necessary control can be achieved by controlling the electric power in order to operate the turbine in the stall region. This control strategy attenuates the stress in the system, while smoothing the power generated. It is shown that the controller can stabilize the nonlinear system using an adaptive current feedback loop. The controller does not need wind velocity or turbine speed, but is based on the current and voltage measured on the dc side of the rectifier connected to the permanent magnet synchronous generator. Maximum power point tracking (MPPT) control is provided in normal operation. Simulation and experimental results are presented. En ligne : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5444990&sortType%3Das [...]