Power limitation in variable speed wind turbines with fixed pitch angle

Variable speed operation of wind turbines has the potential to increase energy capture, to reduce fatigue damage and to reduce aerodynamic noise level. However, one of the most important characteristics of variable speed wind turbines is operational flexibility, which allows the use of different control strategies for above and below rated wind speed. One control strategy which is possible to implement is power capture limitation without using pitch control. In this paper, a control system for power limitation driving the wind turbine to an aerodynamic area is proposed and experimental results obtained from an experimental rig which uses a high performance switched reluctance generator are discussed.