Inter-array cable (IAC) assemblies, systems, and methods are disclosed in which a conductive cable between two floating platforms, e.g., floating wind turbine platforms, is suspended below the sea surface and above the seabed. One or more buoyancy sections are included in the cable, which reduces the static tension on the connection at the floating platform by reducing the suspended cable weight, and which provides geometric flexibility, allowing the IAC to comply with platform motions.

A floating-body type wind turbine power generating apparatus includes a floating body floating on a water surface; and a wind turbine disposed on the floating body and configured so that at least a part of the wind turbine is submersible. The wind turbine includes: at least one blade; a hub to which the blade is mounted; a tower erected on the floating body; a nacelle disposed on the tower; a first electrical device disposed inside the hub or the nacelle; and a second electrical device connected to the first electrical device via a cable and configured to be movable relative to the tower in a vertical direction so as not be submerged upon submergence of the wind turbine.

A cable (10) includes a cable body (11) that is formed from a plurality of wires (14) that are integrally bundled; and a pair of sockets (12) to which both end portions of the cable body (11) is separately affixed; at least one of the plurality of wires (14) being a fiber-containing wire (16), which is formed by an optical fiber (17) that extends in a cable length direction (D) and that is protected by a protective tube (18); wherein the optical fiber (17) protrudes from the protective tube (18), in the cable length direction, further outside than the socket (12); and each of the pair of sockets (12) is provided with a spool (30) that removably holds the optical fiber (17) and imparts an initial tensile strain to the optical fiber (17).

A method for installing an offshore installation is provided, the method including: a) providing a pipe for connecting the offshore installation with another offshore installation or an onshore installation; b) arranging an electrical cable inside the pipe; c) determining a level at or above the seabed, wherein the pipe includes a first portion arranged below the determined level and a second portion arranged above the determined level, and wherein the electrical cable is arranged inside the pipe so as to form a gap with an inner wall of the pipe along the first and second portion; d) determining an amount of cooling liquid such that, when the cooling liquid has a first temperature, the cooling liquid fills the gap along the first portion of the pipe, wherein the second portion of the pipe is free of the cooling liquid, and when the cooling liquid cools the electrical cable.

System for transporting and installing wind turbines on the seafloor, made up of a structure that has adjustable flotation capacity and is made up of two floating hulls and a series of columns onto which they are mounted with the capacity to move over the same, an upper peripheral frame and a lower peripheral frame, on which means are mounted for fastening and manipulating the wind turbines and piles and ferrules for anchoring said wind turbines to the seafloor.

The invention relates to a method of reducing oscillations in an offshore wind turbine comprising one or more thrusters, the method comprising determining an oscillation of the offshore wind turbine and operating the one or more thrusters such that the oscillation is reduced. The invention further relates to an offshore wind turbine comprising one or more underwater thrusters, oscillation determination system for determining an oscillation of the wind turbine and a control system for operating the underwater thrusters in response to signals received from the oscillation determination system.

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.

The present invention provides a floating offshore wind turbine capable of suppressing yawing of a nacelle caused by a gyro effect which is a cause of adverse influence of power generating efficiency of a wind turbine and endurance of devices thereof. The floating offshore wind turbine 10 includes a rotor 11 which is rotated by wind, a nacelle 13 in which a rotation shaft 12 of the rotor 11 is accommodated, and a tower 15 including a turning seated bearing 14 which supports the nacelle 13 such that the nacelle 13 can turn with respect to a sea surface P to exert a weathercock effect. The tower is provided with yawing suppressing means 16 which suppresses yawing T of the nacelle 13. According to this, it is possible to suppress the yawing T of the nacelle 13 generated by a gyro effect caused by yawing Ω generated in the floating body 31 by waves of the sea surface P.

A floatable frame structure has concatenated frame modules, each formed of columns arranged substantially vertically. Neighboring columns are interconnected by upper and lower tie bars and form module sections. The connections between the tie bars and columns have rotary joints arranged at upper and lower nodes on the columns. At least one horizontal rotation joint is arranged for each column in the connection to an associated tie bar, and at least one spherical rotary joint or elastic rotary joint is arranged for each tie bar. Each module section is provided with elastic tensile elements secured to diagonally opposite upper and lower nodes, nodes lying diagonally opposite each other in the same horizontal plane and in the same frame module being connected by elastic tensile elements. Some columns form containers with submersible portions with positive buoyancy, and adjacent frame modules sharing at least one column.

A floating multi-turbine wind power platform for offshore power production, wherein the platform has a substantially elongated shape with an extension direction and being attached to at least two mooring points for securing the platform at its operation site in an original position in relation to the mooring points. The platform includes a device for rotation of the platform (MR1) around an essentially vertical first axis (z1) and further includes at least two wind turbines arranged substantially in a straight line corresponding to the extension direction of the platform and the at least two wind turbines each includes a structural support component and a rotor component. The rotor component is attached to a nacelle which is arranged to rotate using a device for rotation of the nacelle (MR2). The platform further includes a control arrangement (C) arranged to control the device for rotation of the platform (MR1) to rotate the platform only during certain detected wind directions deviating from an original wind direction (WDO) and to limit the rotation of the platform to at the most 90° from the original position, preferably at most ±45°. A method and system are disclosed for aligning rotor components of wind turbines arranged on a floating multi turbine wind power platform according to the above to be essentially perpendicular to a wind direction.