Active flow control for wind turbine blades

Abstract

A method for operating a wind turbine with at least one blade includes providing at least one blade with an active flow control actuator configured to increase an angle of attack range in which the blade or blades can generate torque without flow separation, and using the flow control actuator to adjust this angle of attack range in accordance with load.

1 . A method for operating a wind turbine with at least one blade, said method comprising: 
 providing said at least one blade with an active flow control actuator configured to increase an angle of attack range in which said at least one blade can generate torque without flow separation on said at least one blade; and    using the flow control actuator to facilitate increased power output in a high angle of attack range in accordance with controller inputs.    
     
     
         2 . A method in accordance with  claim 1  wherein said using the flow control actuator comprises limiting operational loads near rated power of the wind turbine.  
     
     
         3 . A method in accordance with  claim 1  wherein said using the flow control actuator comprises using the flow control actuator to effect a decrease in parked loads.  
     
     
         4 . A method in accordance with  claim 1  wherein said at least one blade is configured to continue to operate in case of a failure of the use of the flow control actuator.  
     
     
         5 . A method in accordance with  claim 1  wherein said active flow control actuator is provided at about 60% chord on a suction side of said at least one blade.  
     
     
         6 . A method in accordance with  claim 1  wherein said using the flow control actuator comprises both limiting operational loads near rated power of the wind turbine and using the flow control actuator to effect a decrease in parked loads.  
     
     
         7 . A method in accordance with  claim 1  wherein said using the flow control actuator comprises using the flow control actuator based on environmental conditions at each location of the wind turbine.  
     
     
         8 . A blade for a wind turbine having an active flow control actuator configured to increase an angle of attack range of said blade.  
     
     
         9 . A blade in accordance with  claim 8  having a slender planform.  
     
     
         10 . A blade in accordance with  claim 8  wherein said active flow control actuator is at about 60% chord on a suction side of said blade.  
     
     
         11 . A wind turbine comprising at least one blade having a flow control actuator to increase an angle of attack range in which said at least one blade can generate torque without flow separation and a controller, said controller configured to control the flow control actuator to facilitate increased power output in a high angle of attack range in accordance with controller inputs.  
     
     
         12 . A wind turbine in accordance with  claim 11  wherein said controller is configured to limit operational loads near rated power of the wind turbine.  
     
     
         13 . A wind turbine in accordance with  claim 11  wherein said controller is configured to effect a decrease in parked loads.  
     
     
         14 . A wind turbine in accordance with  claim 11  wherein said blade is configured to continue to operate in case of a failure of said control system.  
     
     
         15 . A wind turbine in accordance with  claim 11  wherein said active control actuator is provided on a suction side of said blade at a position selected to maximize said increase in said angle of attack range.  
     
     
         16 . A wind turbine in accordance with  claim 11  wherein said active control actuator is provided at about 60% chord on a suction side of said blade.  
     
     
         17 . A wind turbine in accordance with  claim 11  wherein said controller is configured to both limit operational loads near rated power of the wind turbine and to effect a decrease in parked loads.  
     
     
         18 . A wind turbine in accordance with  claim 11  having a slender planform.