Back to results
US 4,368,392 AGranted
Water turbine
AssigneePinson Energy Corporation
InventorHerman M. Drees
Life of this patent
Estimating the term…
Abstract
A water turbine for open stream use featuring a vertical-axis cross-flow turbine in which cyclically-pitching blades are supported from one end only to permit the supporting structure and power generation gear to be supported out of the water. In preferred embodiments, there is independent pitch control of the turbine blades to make the blades responsive to the instantaneous flow in their vicinities.
Claims18
A water turbine for generation of electrical power from a flowing body of water, comprising
- a plurality of vertically-extending blades, each with a hydrofoil horizontal cross section,
- a blade support structure supporting the upper ends only of said blades,
- said blade support structure including a central hub and radially extending elements extending from said hub for supporting said blades located radially of said hub,
- an electrical-power generator connected to said central hub,
- pitch control means for cyclically pitching said blades to maintain said blades at useful angles of attack for generation of electrical power, said pitch control means including means for independently controlling the pitch of individual blades in response to the instantaneous local flow conditions in the vicinity of the individual blade, and
- means for supporting said generator and blade support structure above the surface of said flowing body of water so that essentially only said blades penetrate said body of water.
3 more elements
A water turbine for generation of electrical power from a flowing body of water, comprising
- a plurality of vertically-extending blades, each with a hydrofoil horizontal cross section,
- a blade support structure supporting said blades,
- an electrical-power generator connected to said blade support structure,
- pitch control means for cyclically pitching said blades to maintain said blades at useful angles of attack for generation of electrical power, said means including
- means at each individual blade for independently controlling the pitch of said blade solely in response to the instantaneous local flow conditions in the vicinity of said blade to provide said blade with a zero pitch angle twice during each revolution of said turbine at times when said blade moves in a direction parallel to the direction of flow of said body of water and to provide said blade with pitch angles of opposite polarity during the portions of its movement upstream of and downstream of the center of rotation of said turbine.
2 more elements
A water turbine for generation of electrical power from a flowing body of water, comprising
- a plurality of vertically-extending blades, each with a hydrofoil horizontal cross section,
- a blade support structure supporting said blades,
- an electrical-power generator connected to said blade support structure,
- pitch control means for cyclically pitching said blades to maintain said blades at useful angles of attack for generation of electrical power, said means including
- means for independently controlling the pitch of individual blades in response to the instantaneous local flow conditions in the vicinity of the individual blade and for providing the blades with a zero pitch angle twice during each revolution of said turbine at times when said blades move in a direction parallel to the direction of flow of said body of water and for providing the blades with pitch angles of opposite polarity during the portions of their movement upstream of and downstream of the center of rotation of said turbine,
- means for pivoting said blades ahead of their hydrodynamic centers of pressure so that hydrodynamic forces on said blades tend to pitch said blades, and
- means for resisting the pitch induced by hydrodynamic forces so that an equilibrium pitch angle is reached for a given hydrodynamic force on a blade, said equilibrium pitch angle being such as to achieve said useful angle of attack, said means including a pair of springs and a linkage means connected between said springs and said blade for working against one said spring in response to pitch of one direction and working against the other said spring in response to pitch of the other direction, whereby the upstream angle of attack can be adjusted independently of the downstream angle of attack to compensate for stream velocity differences between upstream and downstream.
4 more elements
A water turbine for generation of electrical power from a flowing body of water, comprising
- a plurality of vertically-extending blades, each with a hydrofoil horizontal cross section,
- a blade support structure supporting said blades,
- an electrical-power generator connected to said blade support structure,
- pitch control means for cyclically pitching said blades to maintain said blades at useful angles of attack for generation of electrical power, said means including
- means for independently controlling the pitch of individual blades in response to the instantaneous local flow conditions in the vicinity of the individual blade and for providing the blades with a zero pitch angle twice during each revolution of said turbine at times when said blades move in a direction parallel to the direction of flow of said body of water and for providing the blades with pitch angles of opposite polarity during the portions of their movement upstream of and downstream of the center of rotation of said turbine,
- means for pivoting said blades at or near to their hydrodynamic centers of pressure,
- a pitch control blade extending vertically into said body of water in the vicinity of an individual said blade,
- frame means for supporting said control blade,
- means for pivoting said frame means and control blade independently of said associated blade about a vertical axis spaced from said control blade, and
- stop means attached to and pivoting with said frame means for prescribing the pitch of said individual blades.
7 more elements
Dependencies are inferred from the claim text.