20100129215 | SYSTEM FOR PROVIDING DYNAMIC PITCH CONTROL IN A WIND TURBINE - A system for providing dynamic pitch control in a wind turbine. In accordance with an embodiment, the dynamic pitch control uses a starting spring to pitch the blades of the wind turbine into a starting position that is suited for very low wind speeds. The pitch control then automatically pitches the blades into a run position as the rotation speed increases, using a combination of a rotational mass and a restraining spring. This allows the turbine to be started, and to generate power, at a much lower starting wind speed yet still operate at optimal speeds in its typical running range. In accordance with an embodiment, as the wind speed further increases beyond an overspeed limit, the rotational mass overcomes its restraining spring, and automatically pitches the blades back toward and beyond their start position, reducing the likelihood of damage to the turbine caused by high rotation speeds. | 05-27-2010 |
20100133852 | VERTICAL AXIS WIND TURBINE WITH VARIABLE AREA - A vertical axis wind turbine with variable area. In accordance with an embodiment, the vertical axis wind turbine comprises a vertically-oriented central mast, and a plurality of vertically oriented multi-section blades that are arranged around and coupled to the central mast. Each blade includes an outer section, and an inner section that can be telescoped with the mast, and relative to the outer section, to change the effective length and surface area of the blade. In accordance with an embodiment multiple sections can be telescoped in such a fashion to vary the area of the blade. A pneumatic or other controller can raise and lower the central mast and effect a corresponding change in the overall area of the wind turbine. This allows the area to be increased for use with lower wind speeds; and reduced for use with higher wind speeds. Adjusting the area of the wind turbine allows for power generation over a wider range of wind speeds, and more control over the maximum power output of the turbine, including the ability to depower the turbine in very high wind speeds, and reduce the likelihood of damage. | 06-03-2010 |