Windpower system

A windpower system comprising

• A. a support,
• B. a turbine shaft rotatively mounted to the support,
• C. a turbine having variable pitch blades rotatively mounted to a hub connected to one end of said turbine shaft,
• D. torque take-off means connected to said turbine shaft,
• E. a control shaft rotatively mounted to the support,
• F. means for increasing blade pitch when the rotation of the turbine shaft in an intended winddriven direction is faster than that of the control shaft and decreasing blade pitch when the turbineshaft rotation in the intended direction is slower than the control-shaft rotation in the intended direction, and
• G. an electrical brake acting between the support and the control shaft so that by engaging the brake, the blades can be moved to their fully feathered position solely by the torque developed by the rotating turbine, said electrical brake engaging when deenergized so that in the event of a power failure, the turbine blades are feathered.

A windpower system comprising

• A. a support,
• B. a turbine shaft rotatively mounted to the support,
• C. a turbine having variable pitch blades rotatively mounted to a hub connected to one end of the turbine shaft,
• D. torque take-off means connected to said turbine shaft,
• E. a control shaft rotatively mounted to the support,
• F. means for changing the pitch of the blades in response to the relative motion of the control shaft and the turbine shaft, the pitch changing means including linear actuating means rotatively fixed to the turbine shaft and whose linear position relative to a reference position is indicative of the pitch angle of said blades,
• G. a brake acting between the support and the control shaft so that by engaging the brake, the blades can be moved to their fully feathered position solely by the torque developed by the rotating turbine, and
• H. means for disengaging the brake and rotatively coupling the control shaft and turbine shaft when the blades reach their feathered position so as to maintain the blades in that position, the disengaging and coupling means including:
• (1) brake release means extending to the brake, said release means mechanically disengaging the brake when moved, and
• (2) means on the actuating means for moving the release means and frictionally engaging the control shaft when the actuating means has moved linearly to a position corresponding to the feathered position of the blades.

A windpower system for generating a rated output power comprising:

• A. a support;
• B. a turbine shaft rotatably mounted on the support;
• C. a turbine to be propelled by wind, the turbine including a hub and having a variable-pitch blades rotatably mounted on the hub for rotation among positions including a full-power position, a feathered position, and a so-called scram position between the latter two positions;
• D. a generator coupled to the turbine shaft for driving by the turbine to generate power;
• E. means for monitoring the pitch of the blades to indicate when the blades are in the feathered position, the scram position, and the full-power position;
• and
• F. means for controlling the blade pitch to tend to achieve the rated output power but for moving the blades to their feathered positions if wind speed is so high that the rated output power is sustained even when the blades are in their scram positions.