Patent ID: 7896614

Claim:
A wind turbine, comprising: a turbine blade connected to a rotor hub, said turbine blade comprising a low pressure surface and a high pressure surface; an electrical stall sensor configured on at least one of said low pressure surface or said high pressure surface at a location to detect backflow in a stall condition at said respective pressure surface, said stall sensor further comprising: a power supply; a flap pivotally configured relative to said respective pressure surface so as to be moved from a first position towards a second position by backflow over said respective pressure surface; a sensor circuit that responds to movement of said flap between said first and second positions and generates a corresponding electrical signal that indicates a stall condition; and a controller, said stall sensor in communication with said controller to provide an input variable to said controller indicative of a stall condition, said controller configured to change an operating function of said wind turbine in response to the stall condition.