Floating offshore wind power generation facility

Patent metadata

Field	Value
Publication number	US-9777713-B2
Application number	US-201414774939-A
Country	US
Kind code	B2
Filing date	Mar 3, 2014
Priority date	Mar 13, 2013
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A floating offshore wind power generation facility includes a floating body, a mooring cable, a tower, and a windmill installed at the top of the tower, the windmill including a nacelle and a plurality of blades. The rotation axis of the windmill has a predetermined upward angle to avoid contact between the blades and the tower, and the windmill is of a downwind type in which the blades are attached to the leeward side of the nacelle and installed with the back surfaces of the blades facing windward, and the mooring point of the mooring cable to the floating body is set at a position below the surface of the sea and higher than the center of gravity of the floating body.

First claim

The invention claimed is:

1. A floating offshore wind power generation facility comprising
a floating body, a mooring cable, a tower, and a windmill installed at a top of the tower, the windmill including a nacelle and a plurality of blades, wherein
the rotation axis of the windmill has a predetermined upward angle, and the windmill is a downwind windmill, in which the blades are attached to the leeward side of the nacelle and installed with the back surfaces of the blades facing windward,
the mooring cable is attached to the floating body at a mooring point below the surface of the sea and higher than the center of gravity of the floating body,
the floating body has a lower concrete floating body structure formed of concrete precast cylindrical bodies which are formed into cylindrical shapes having a same cross-sectional shape along planes which are perpendicular to an axial direction of the concrete floating body structure, and which are stacked in a direction of height, and each cylindrical body is connected along the height direction with a steel material, and wherein an upper steel floating body structure is provided on an upper part of the lower concrete floating body structure and wherein
each of the concrete precast cylindrical bodies is composed of a plurality of split cylindrical bodies joined to each other along a circumferential direction of the concrete precast cylindrical bodies,
each concrete precast cylindrical body comprises outer cables under tension wound around an outer circumference of the respective concrete precast cylindrical body, and
wherein the cables have first ends and second ends, and the first ends are anchored to a first anchoring device on the respective concrete precast cylindrical body and the second ends are anchored to a second anchoring device on the respective concrete precast cylindrical body, wherein the first and second anchoring devices face each other along a diametrical direction of the respective concrete precast cylindrical body, and wherein each outer cable is positioned around a first circumferential side or a second circumferential side of the respective concrete precast cylindrical body and wherein a number of outer cables positioned around the first circumferential side of the respective concrete precast cylindrical body are the same as a number of outer cables positioned around the second circumferential side of the respective concrete precast cylindrical body.

2. The floating offshore wind power generation facility according to claim 1 , wherein a plurality of yaw-suppressing fins protruding from a circumferential surface of the floating body are provided on the lower portion of the floating body around the circumferential surface with spacing between adjacent yaw-suppressing fins.

3. The floating offshore wind power generation facility according to claim 1 , further comprising ballasts having a weight that has been determined so that, when wind acts at an average wind velocity, the blades rotate in a rotational plane that is a substantially vertical plane.

4. The floating offshore wind power generation facility according to claim 1 , wherein the outer cables are spaced from one another in an axial direction of the respective concrete precast cylindrical body.

5. The floating offshore wind power generation facility according to claim 1 , wherein each of the anchorage devices includes a lifting fitting for lifting the concrete precast cylindrical body.

6. The floating offshore wind power generation facility according to claim 1 , wherein the split precast cylindrical bodies are formed by splitting the precast cylindrical bodies in the circumferential direction.

7. A method of producing and installing a floating offshore wind power generating facility, comprising producing and installing the floating offshore wind power generating facility of claim 1 , which comprises producing the concrete floating body structure of the facility of claim 1 by stacking and joining the plurality of individual concrete precast cylindrical bodies to each other to form an integral concrete precast cylindrical body, removably winding and fastening the outer cables around the outer circumference of the integral concrete precast cylindrical body, and, after final assembly of the concrete floating body structure with other components to produce the facility of claim 1 and installing the facility of claim 1 , removing the outer cables from the integral concrete precast cylindrical body.

Assignees

• Toda Corp
• Univ Kyoto
• Hitachi Ltd
• Hitachi Ltd

Inventors

• Sato Iku
• Asano Hitoshi
• Utsunomiya Tomoaki
• Yoshida Shigeo

Classifications

• B63B2039/067

  effecting motion dampening by means of fixed or movable resistance bodies, e.g. by bilge keels · CPC title

• F03D13/25

  specially adapted for offshore installation · CPC title

• B63B2001/044

  with a small waterline area compared to total displacement, e.g. of semi-submersible type · CPC title

• B63B2021/505

  Methods for installation or mooring of floating offshore platforms on site · CPC title

• F03D13/10 Primary

  Assembly of wind motors; Arrangements for erecting wind motors · CPC title