Ring-based Vertical-Axis Wind Turbine (VAWT) System

Abstract

To provide high stability at low cost, a ring-based floatation system for a floating vertical-axis wind turbine is proposed. The system uses a buoyancy torus with a finite shell thickness, which can be sealed to prevent water from leaking inside the torus. This torus shape has an outside and inside diameter on a horizontal plane while having a circular cross-section in a vertical plane. This buoyancy torus serves as a floatation tube to provide buoyancy at a large maximum radial extent to enhance platform stability in terms of both inertia and metacentric height. The torus shape (or a similar faceted shape made of several cylindrical tubes connected in a circle) also provides high radial asymmetry and high structural robustness. This buoyancy torus supports rotating wind turbine blades which are affixed to a rotation ring, where the torus and the rotation ring have the same axis of revolution and where the blades and the rotation ring rotate about this axis of revolution. One or more electrical generators can be placed between the rotation ring and the buoyancy torus (or a foundation for an onshore wind turbine) to convert the rotational power of the blades (communicated to the rotation ring) into electrical power. This ring-based buoyancy platform can be ballasted by a variety of methods and can also be used to support offshore oil and gas drilling platforms.

Dependencies are inferred from the claim text.