Governed vane wind turbine
OwnerEirik Samuelsen, Sverre Schiotzinventors
Life of this patent
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Abstract
Wind energy converting machine comprising a solid rotating ring carrying airfoils which are governed to have an optimal angle of attack to the wind approaching each of them when the wind velocity is below a chosen limit. In stronger wind the angles of attack are decreased to limit the power uptake. The ring is supported by stationary rollers which act as friction wheels to transfer the power to electric generators or the like. An example is described in which 90 airfoils, 30 meters high and with 3.6 meters root chord, perform a track of 200 meters diameter, at a speed of 8 m/sec. This turbine is calculated to produce 3.75 megaWatt in a wind of a velocity of 10 m/sec. or higher.
Claims23
A method for extracting power from the wind, including the steps of:
- supporting plural airfoils on a circular structure which rotates by coaction of the airfoils with the wind, orienting the plural airfoils in response to wind position and as a function of the changing position of the airfoils as the circular structure rotates, supporting the circular structure on a plurality of roller means, extracting rotational energy from said roller means and adjusting the pressure each roller means exerts on the circular structure as a function of wind power to achieve a normalized output.
In a vertical axis wind turbine comprising a number of substantially vertical airfoils arranged in a circular line on a horizontally arranged and substantially circular structure wherein each of the airfoils may be rotated about a vertical axis relative to the circular structure by a governing system and wherein the circular structure simultaneously is free to rotate upon and entirely supported by a number of stationary rollers each supported by a bearing, the improvement comprising:
- stationary rollers in the form of cones whose vertices coincide with the center of the supported surface of the circular structure, and
- at least one of said stationary rollers including planetary gear means therein for transferring wind energy to a complementary gear of a stationary energy converter, the wind energy transferred by friction between said stationary roller and the circular structure.
The wind turbine described in claim 21, wherein the bearing of said roller is capable of being displaced along its axis to vary the ratio of the rotational speed of said roller to the rotational speed of the circular structure.
In a vertical axis wind turbine comprising a number of substantially vertical airfoils arranged in a circular line on a horizontally arranged and substantially circular structure, wherein each of the airfoils may be rotated about a vertical axis relative to the circular structure by a governing system and wherein the circular structure simultaneously is free to rotate upon and entirely supported by a number of stationary rollers, each supported by a bearing, the improvement comprising airfoils including a number of separate leg portions extending upward from the base of the airfoil, of which leg portions two are leaning outward to the extremes of the chord of the profile of the airfoil and the other leg portions are leaning inward to intermediate points on the rim of the profile of the airfoil, said leg portions constituting the weakest part of the airfoil under the load of wind forces.
In a vertical axis wind turbine comprising a number of substantially vertical airfoils arranged in a circular line on a horizontally arranged and substantially circular structure, wherein each of the airfoils may be rotated about a vertical axis relative to the circular structure by a governing system and wherein the circular structure simultaneously is free to rotate upon and entirely supported by a number of stationary rollers each supported by a bearing, the improvement comprising stationary rollers in the form of cones whose vertices coincide with the center of the supported surface of the circular structure.
In a vertical axis wind turbine comprising a number of substantially vertical airfoils arranged in a circular line on a horizontally arranged and substantially circular structure, wherein each of the airfoils may be rotated about a vertical axis relative to the circular structure by a governing system and wherein the circular structure simultaneously is free to rotate upon and entirely supported by a number of stationary rollers each supported by a bearing, the improvement comprising at least one of said stationary rollers including planetary gear means therein for transferring wind energy to a complementary gear of a stationary energy converter, the wind energy transferred by friction between said stationary roller and the circular structure.
A method of governing a vertical axis wind turbine comprising a number of substantially vertical airfoils arranged in a circular line on a horizontally arranged and substantially circular structure, wherein each of the airfoils may be rotated about a vertical axis relative to the circular structure by a governing system and wherein the circular structure simultaneously is free to rotate upon and entirely supported by a number of stationary rollers each supported by a bearing, said method comprising the steps:
- causing the airfoils by the governing system to follow a pattern in which the airfoil moving directly windward has its chord parallel to the wind direction and the airfoil moving directly leeward has its chord in right angle to the wind direction while airfoils in intermediate positions in one hemicycle steadily increase their angle to the wind direction and airfoils in the other hemicycle decrease their angle to the wind direction.
- orienting the airfoils by the governing system through the greater part of the circular track, except in a smaller sector around the point where they are moving leeward, to have angles of attack to the wind approaching them so that the sum of the tangential components of the wind forces exerted upon them are nearly maximized in the direction of the rotation,
- orienting the airfoils by the governing system through a smaller sector around the point where they are moving leeward, to have their leading edge pointed toward the undisturbed wind when the wind velocity exceeds the airfoil's peripheral velocity and to have their trailing edge pointed toward the undisturbed wind when the wind velocity is less than the airfoil's peripheral velocity, and
- orienting the airfoils by the governing system to have angles of attack relative to the wind approaching them, of a magnitude that makes the sum of the tangential components of the wind forces nearly independent of the velocity of the undisturbed wind when their velocity exceeds a chosen value.
Dependencies are inferred from the claim text.