TW202411118A - Anchoring system and method of installing a floating platform using said anchoring system - Google Patents

Abstract

An anchoring system for floating platform which eliminates the pitch and roll movements of the floating platform using anchoring lines attached to the seabed, which are supported by several pulleys or rotary fixing means of the floating platform and are all joined in a common counterweight hanging from the floating platform. Each anchoring line comprises a direct subline and a cross subline, which maintain the counterweight always located in correspondence with the central axis of the floating platform. It also describes a novel method for installing the floating platform at its destination without the aid of special ships.

Description

Anchor system and method for installing a floating platform using the anchor system

The present invention relates to an anchoring system, and in particular to an anchoring system suitable for a floating platform for serving as a base for a wind turbine located in the sea.

Floating platforms, especially those dedicated to supporting wind turbines for generating electricity from offshore wind energy, require anchoring systems to keep the floating platform in place and to contribute to its stability.

In the art, platforms of the Tension Leg Platform (TLP) type are well known. These platforms comprise three or more anchoring lines (usually chains or cables connecting a platform with piles anchored to the seabed). The anchoring lines of a TLP platform are designed to be set in tension, connecting the platform in an upright position to each pile anchored to the seabed. A TLP platform comprises a set of buoys designed to generate excess buoyancy of the platform (taking into account the weight of the structures sitting on the platform). The excess buoyancy ensures a high tension of the cables, which ensures that the platform is always upright. In this way, longitudinal and transverse movements of the platform and of the structures sitting on it are avoided.

European Patent No. EP 2743170 A1 describes the TLP platform described in the preceding paragraphs.

The disadvantage of TLP platforms is that the high tension of the cables is required to maintain them in a vertical position and avoid swaying and/or rolling movements which also result in obstructed movement of the platform in the vertical direction. Therefore, when the tide rises, the platform cannot move upwards (due to the fact that the anchor lines are shortened or inextensible), so it is necessary to consider increasing the tension of the anchor lines. This leads to a high risk of anchor line breakage and requires having high-positioned anchor lines or increasing the number of anchor lines. Furthermore, in TLP platforms, in very low tide conditions, the platform also drops and the anchor lines can relax a lot of tension, increasing the platform's vertical and lateral movement to uncontrollable conditions, and also increasing the risk of sway and/or roll (due to the thrust of wind and/or waves on the platform and the structures on it), which can lead to the platform capsizing.

In order to avoid the aforementioned disadvantages, other types of platforms are known in which the anchor lines are connected to the counterweight via pulleys on the platform. These types of platforms allow vertical and lateral displacement of the platform in the face of tides, waves and wind, thus making it unnecessary to have a large number of anchor lines or anchor lines at high locations.

Spanish Patent No. ES 2629867 A2 describes the platform described in the preceding paragraphs.

The problem with the anchoring system described in the patent document mentioned in the preceding paragraph becomes more important when the floating platform using the anchoring system is subjected to longitudinal and/or lateral movement. The anchoring system described in the preceding patent document is not optimally suited for:

- The platform's movements may cause seasickness to personnel (i.e. other than marine professionals), typically children, passengers, scientists, visitors and tourists;

- For offshore wind turbine installations on floating platforms, it is important to avoid lateral and/or excessive longitudinal roll of the platform.

- Equipment installation applications where the required movement or acceleration of the platform is minimal during the operation (laboratory, research center, factory);

- Floating platforms may (at certain points) be subject to extremely severe storms that may jeopardize the safety of the same structure or may capsize it (if the longitudinal and lateral rolling motions are very severe).

One object of the anchoring system of the present invention comprises a set of anchoring cables or chains (anchoring wires) fastened to foundation piles buried in the seabed or fastened to vertical weights located or set on the seabed.

One purpose of the anchoring system of the present invention is to have unique characteristics, making it suitable for use on floating platforms as the base of offshore structures, which is very important to avoid longitudinal or lateral movement, while solving certain shortcomings of other anchoring systems used for floating platforms in the field of technology.

The invention also relates to a method for installing a floating platform using the anchoring system.

One purpose of the anchoring system of the present invention is to be applied to any type of structure intended to be set up as a floating platform on the sea surface, which requires a number of anchoring points on the seabed for fastening cables or anchoring chains of the floating platform.

In order to remedy the aforementioned shortcomings, the present invention relates to an anchoring system.

The anchoring system of the present invention includes a floating platform (for example, for supporting a wind turbine) and at least one pair of anchoring lines (for example, anchoring cables or anchoring chains), and at least one bottom portion of each anchoring line is configured to fix or anchor the floating platform to the seabed (for example, to a foundation pile driven into the seabed, or to a counterweight or to an anchoring ring set on the seabed).

Each anchor line also includes a center portion to which the counterweight is attached.

Each pair of anchor lines includes two anchor lines arranged in a plane passing through the central axis of the floating platform. These anchor lines are arranged in the same plane and are respectively located on one side of the central axis of the floating platform.

The central axis of the floating platform preferably defines the radial symmetry of the floating platform.

The anchoring system includes at least one first rotating fixture (such as a pulley) for each anchor line, wherein each first rotating fixture is fixed to a first point of the floating platform and is configured at a first point of the floating platform to fix each anchor line to the floating platform, allowing the anchor line to slide on the first rotating fixture.

In the anchoring system of the present invention, the new features are as follows:

- Each anchoring line comprises at least one direct sub-line and one cross sub-line. These sub-lines are chains or cables that run parallel at least at their bottom. Each direct sub-line runs from the first rotating fixture to the counterweight and does not pass through the central axis of the floating platform. The first rotating fixture can be formed, for example, by a pulley with two grooves (for the passage or sliding of the two anchoring sub-lines) or by a set of two pulleys.

- The anchoring system comprises at least one second rotating fixture (e.g. a pulley) for each anchoring line, wherein each second rotating fixture is fixed to a second point of the floating platform and is configured to fix each cross sub-line of each anchoring line to the floating platform at the second point of the floating platform, allowing the cross sub-line to slide on the second rotating fixture, so that each cross sub-line is routed from the first rotating fixture to the counterweight, first passing through the central axis of the floating platform, and secondly sliding on the second rotating fixture.

By means of the above-described anchoring system, the longitudinal and/or lateral roll of the floating platform can be eliminated or drastically reduced, in contrast to other anchoring systems, such as that described in Spanish Patent No. ES 2629867 A2, which allow limited horizontal movement while leaving the floating platform free to move vertically.

By means of the above-mentioned anchoring system, the pulley system used in other anchoring systems by pulleys and cables in the art is mechanically simplified. Since there is no center pulley at the position corresponding to the center axis of the floating platform, the anchoring system is simpler, and all the center pulleys of all the arms make the anchoring system not overlap at almost the same point.

Furthermore, by means of the above described anchoring system, the pendulum motion characteristic of the center weight caused by the vertical motion of the platform due to waves can be eliminated.

Likewise, by means of the above described anchoring system, the need to have a central well in the body of the platform (main or central structure) is eliminated, where the art requires a passage in the middle of the anchoring line (this part grabs the central counterweight).

Preferably, the floating platform comprises a pair of projecting structural arms for each pair of anchoring lines. Thus, each pair of projecting structural arms comprises a first arm and a second arm, arranged symmetrically with respect to the central axis of the floating platform. Each projecting structural arm is attached to the main structure (or body) of the floating platform. Each projecting structural arm extends radially from a first end attached to the main structure of the floating platform to a second end projected outside the floating platform. Thus, at least one first rotating fixture is fixed to the floating platform corresponding to the second end of the first arm, and at least one second rotating fixture is fixed to the floating platform at a point corresponding to the position of the second arm.

The main structure (or body) of the floating platform may have the shape of a cylindrical shaft, a conical shaft, or a pyramidal shaft. In addition, the anchoring system may include a plurality of spokes connected to the main structure, and at each free end of each spoke, there is a floating element. These floating elements may include at least one submerged chamber.

The main structure (or hull) of the floating platform may lack the aforementioned radials with floating elements at their ends. However, the main structure or hull having an axial geometry may include at least one floating element. This at least one floating element includes at least one submerged chamber.

The floating elements provide buoyancy and when submerged, reduce weight, allowing the floating platform to be moved or towed to its installation location or position, followed by submerging the corresponding floating elements to provide tension to the anchor cables, increasing their stability.

When the floating elements are located at the ends of the beams attached to the bearings, the structure is particularly stable and suitable for ensuring the stability of the floating platform under such installation maneuvers.

Instead of geometric bearings, the main structure (or hull) of the floating platform may include a ring-shaped geometry, which is attached to a cylindrical, conical or pyramidal shaft by spokes. This main structure may constitute a floating ring (floating or annular floating element). This floating ring may include at least one submerged chamber.

The structure of the floating ring also provides good stability for the floating platform.

The anchoring system may include at least one third rotating fixture (e.g., pulley) for each anchor line. Each third rotating fixture is fixed to a third point of the floating platform and is configured to fix each direct sub-line of each anchor line to the floating platform at the third point of the floating platform, allowing the direct sub-line to slide through the third rotating fixture, and each direct sub-line is routed from the first rotating device to the counterweight by the passage and sliding of the third rotating fixture.

This third rotating fixture allows direct sub-line routing in the middle portion parallel to one of the protruding structural arms, so that the central portion (which runs directly from the third rotating fixture to the counterweight) is routed close to the central axis of the floating platform.

In addition, the anchoring system may include at least one rotating guide device (such as a pulley or a groove wheel) for each anchoring line, wherein each rotating guide device is fixed to a fourth point of the floating platform and is configured to guide the track of the cross sub-line of each anchoring line, allowing the cross sub-line to slide through the rotating guide device, so that each cross sub-line is routed between the first rotating fixture and the second rotating fixture through the rotating guide device.

The rotation guide allows the cross-wires to avoid obstructions on their path from the first rotation fixture through the central axis to the second rotation fixture. By means of the rotation guide, collisions of the cross-wires of all anchor lines with each other or with the main structure of the floating platform can be avoided.

Preferably, each bottom portion of each anchor line comprises a buoy, dividing the bottom portion into a first portion running between the seabed and the buoy, and a second portion running between the buoy and at least one first rotating fixture.

The above features facilitate the installation of the floating platform, since the bottom weight, foundation pile or anchor ring of the first part attached to the bottom (with the buoy) can be arranged in a predetermined installation position (once the position of the floating platform is approached), and then when the floating platform and the counterweight have been moved to the installation position, the second part connected to the bottom is directly connected to the buoy.

Preferably, the counterweight of the anchoring system includes at least one submerged buoyancy chamber. This feature also facilitates the transportation of the counterweight (it can be transported without being submerged because it has a lower weight), and also facilitates the progressive contribution to the anchoring line when the at least one submerged buoyancy chamber is filled.

The present invention also relates to a method for installing a floating platform using the above-mentioned anchoring system.

Therefore, the method for installing a floating platform of the present invention comprises:

- arranged and/or anchored to the seabed at the location or installation site of the floating platform by means of at least one anchor and/or at least one bottom weight and/or at least one anchoring ring and/or a set of foundation piles;

- Move the floating platform and counterweight to its installation location, which is a location with at least one flooded chamber that is not flooded.

- Secure the free end of the bottom of each anchor line:

to at least one anchor and/or at least one bottom weight, and/or at least one anchor ring and/or a set of foundation piles, or

to the buoy, previously attached by means of a first portion of the bottom of the anchoring line to at least one anchor and/or at least one bottom weight, and/or at least one anchoring ring and/or a set of foundation piles;

- secure the free end of the middle part of each anchor line to the counterweight;

- Towing the side of the floating platform until the anchor lines are taut; and

- Flooding of at least one buoyancy chamber.

In the anchoring system of the present invention, the floating platform does not need a static bottom, because it can withstand very severe storms, so it is suitable for areas of any seabed depth, including near the coast (e.g. 80 meters deep), and far from the coast (reaching a depth of 1000 meters or more), and at any intermediate distance.

In a preferred embodiment of the anchoring system of the invention, several platforms (for offshore wind turbines) are presented, inherently stable in all their possible states, from manufacturing in the port, through the transport to the wind farm and the assembly phase of the system wiring, submerging the counterweight and the final adjustment, to its final operational state. Therefore, the installation process is very simple and fast. No special vessels are required, only conventional small tugboats are sufficient.

The anchoring system of the present invention allows the detachment and movement of the floating platform to another location through a novel, simpler and faster procedure than that of Spanish Patent No. ES 2629867 A2.

The main features and advantages of the anchoring system of the present invention are:

- It can be applied to any type of platform, in particular windmills and platforms dedicated to offshore leisure activities;

- It completely avoids the platform's vertical and horizontal movement, but allows horizontal and vertical movement;

- It requires no foundations and no special preparation of the seabed (although simpler conventional foundations can be used);

- Optimal draughts are between 50 and 400 metres, although greater depths are possible;

- It can be installed or relocated (if necessary multiple times) without the need for a specific vessel, but only by using a tugboat;

- It can be used to capture wave energy by means of one or more simple conventional generators.

- The forces presented at the anchor lines are much less than TLP platforms; if one of the anchor lines breaks, it can still work with the other anchor lines. In addition, it can be repaired/replaced in place;

- It allows the design of platforms that are lighter (thus cheaper) and have fewer pillars (resulting in less visual impact).

The anchoring system of the present invention is applicable to any floating offshore installation where the need for movement is an important design consideration, especially in the following situations:

- Tourism, marine leisure and nautical sports: the platform design with this type of anchoring is ideal for use in the hotel and entertainment industry, since most potential customers of this type of facility are not professional sailors and the fact that its movements are very small is extremely attractive; it is possible to set up hotels, placing them in extraterritorial waters more than 10 nautical miles from the coast, thus having leisure facilities, entertainment, nightclubs, game rooms, theme parks or any type of facility for equivalent installations on land, which have urban obstacles or difficulties in obtaining opening permits or difficulties in current regulations; far from the coast, the seabed depth is very large and it is impossible to support the hotel on the seabed; in addition, when the waves are very strong, the traditional platforms used in this application will move excessively.

- Wind farms. Windmills require the smallest possible movement of their base. In fact, a significant degree of pitch (tilt), or a significant degree of acceleration is exceeded, the wind turbine must be stopped for safety reasons. The fact that its movement is less than that of existing platforms increases the profitability of the installation, by having more than the net number of hours per year of electricity produced. In fact, all preferred embodiments presented in this patent application are preferably platforms specifically designed for supporting offshore wind turbines.

- Alternative energy sources. Quite naturally, the proposed system reduces the pitch angle of the platform by extracting energy from the conversion action of the main floaters (floating elements). This is achieved by adding an electric generator to one of the pulleys (2 or 3) of the vibration absorbing line. The generated electricity can be used for the self-consumption of the installation or sent to the land via corresponding cables. Indeed, the invention can be approached from two points of view:

As a collector of renewable energy: the system extracts energy from the movement of the platform caused by waves while eliminating the platform's awkward pitch and roll motions;

As a comfort device: the system cancels the platform's pitch and roll motion and also generates energy from the waves.

From a second point of view, the energy extracted from the damping wire can be dissipated directly in the form of heat, or it can be converted into electrical energy. If it is dissipated, the required equipment will be cheaper and simpler, the movement of the platform will be the same, but the overall potential of the system will not be reduced. If it is decided to use the surplus energy, it can be stored in batteries or consumed in the platform's facilities.

Therefore, one or more damping wires, with or without energy harvesters, may be included in the anchoring. The basic task of these wires is to reduce the vibrations (oscillations), which can be achieved by the elasticity of the anchoring cables. In the system, conceptually quite stiff (usually it is a theoretical system). These low/medium frequency vibrations can significantly increase the acceleration of the platform and make it unacceptable. The addition of vibration absorbing wires almost completely eliminates these vibrations (oscillations).

These damping lines are very similar to locking anchoring lines (the anchoring line is attached to an anchoring element or a foundation pile on the seabed), the difference is that one of the pulleys (internal or external) drives an electric generator (if the energy is to be used) or a hydraulic or electrical dissipator (if it only functions as a damper).

As described above, the present invention relates to an anchoring system including a floating platform 100.

Some of the elements referenced in this description are defined as follows.

Float or floating element 500: A closed and waterproof package, fully or partially submerged in water, which can withstand the hydrostatic or dynamic pressure of waves or currents. If it is partially submerged, it can also withstand the forces from the wind on its sides or superstructure.

Platform or main structure 400: The structure includes one or more waterproof floats or floating elements 500, forming a strong and resistive assembly, at least one of which is partially submerged.

Floating platform 100: a platform or main structure 400 of any shape or configuration, further including other elements or structures (sprays 600, projecting structural arms 12, floating elements 500, etc.), dedicated to any function (accommodation, industrial or entertainment facilities, windmill support, etc.), utilizing the anchoring system proposed herein.

External forces: wind, currents, waves, internal load movement, or any element external to the floating platform 100 that attempts to move it away from its designed position or attempts to transmit pitch or roll motion.

Cable or anchor wire 200 tension: The tensile force to which the cable or anchor wire 200 is subjected (due to its natural elasticity, the cable cannot withstand compression).

Central counterweight 1: The platform is completely submerged, with an average density greater than 12 kg/dm ³ , and keeps the anchor line 200 connected to it taut. In a simple installation, there is only one counterweight 1 located on the central axis 300 of the floating platform 100, but there may be several counterweights, or located at other points of the floating platform 100.

Anchor or bottom weight 4: A (large) weight supported on the seabed 5 to which the cables or anchor lines 200 of the anchoring system are attached. In other conventional installations, it is equivalent to an anchor or "dead weight", keeping a buoy or other marine element in its position, or any other type of anchoring by means of piles.

Anchor cables or anchor lines 200: cables, chains or any type of connection that keeps the floating platform 100 attached to the bottom weight 4 to prevent the floating platform 100 from being dragged by external forces. Each anchor line 200 is composed of the following elements:

- Bottom leg 8: part of the anchor line 200, which connects the bottom weight 4 with the first rotating fixture 3 (or external pulley) of the anchor line 200. In most applications, the bottom leg 8 is completely vertical in the projection, although in special cases it may diverge slightly. In some cases, it can reach the seabed 5 in a single piece; in other cases, the bottom leg 8 is separate or divided into a first part (lower part) and a second part (upper part), and the two parts (upper and lower) are connected together by an intermediate buoy 9.

- Middle part 7: the part that anchors the line 200 and connects the outer pulley (first rotating fixture 3) with the inner pulley or pulleys (second rotating fixture 2c) and finally the third rotating fixture 2d that pulls the cable; it can be horizontal or it can have a slight inclination (if the pulleys are not at the same height).

More specifically, as shown below, the anchor line 200 includes a cross line 200c and a straight line 200d. The middle portion 7 is a portion of the cross line 200c of the anchor line 200, connecting the first rotational fixture 3 (or outer pulley) and the second rotational fixture 2c (or inner pulley).

Furthermore, in the case of the third rotational fixing device 2d (or the inner pulley), the intermediate portion 7 also refers to the portion of the direct sub-line 200d of the anchor line 200, which connects the first rotational fixing device 3 and the third rotational fixing device 2d.

- Central part 6 : the part of the anchoring line 200 which connects the inner pulley (or each inner pulley) to the central counterweight 1 .

- Intermediate buoy 9: optional element, which can be inserted in the bottom 8 of each anchor line 200. The buoy 9 is attached to the seabed 5 by means of cables (the first part of the bottom leg 8 of the anchor line 200). The first part of the bottom leg 8 can include one or more parallel cables or chains. The advantage of using the buoy 9 is that it can be pre-installed, when the bottom weight 4 is placed in the ground, lifting it at the correct height, and then when installing the floating platform 100, one only needs to connect the anchor lines 200 (the second part of the bottom 8 of each anchor line 200) to the buoy 9, which is ready with the correct length, significantly speeding up the installation process of the floating platform 100.

- Central axis 300 of the anchoring system: vertical axis, passing through the center of mass of the counterweight 1 in the static (or projected) position. Preferably, this central axis 300 constitutes the symmetrical central axis 300 of the floating platform 100 .

- Anchor wire (common name): The basic unit of the anchor system, consisting of the following components:

The mooring weight (or bottom weight 4) is supported on the seabed 5 (which may be shared by several mooring lines);

. The first rotating fixture 3 (or external or external pulley): fixedly or partially elastically (or rotating/tilting) fastened to the floating platform 100, close to the vertical position of the bottom weight 4;

One or two inner or internal pulleys 2 (second rotational fixing means 2c), and optionally third rotational fixing means 2d: fixedly or partially elastically (or rotationally/tiltedly) fastened to the floating platform 100 at certain points of the floating platform 100 structure. Despite the name, they are at a considerable distance from the central axis 300 of the floating platform 100.

. The corresponding part of the central counterweight 1 (several cables must share the same counterweight 1);

The cable connecting all these elements is made up of the parts defined above (central part 6, middle part 7 and bottom part 8);

Optionally, a middle buoy 9 may be sandwiched in the bottom 8;

Optionally, there may be some intermediate pulleys (rotating guides 11) used to support the middle portion 7 of the cable anchoring the sub-wires, or to assist in turning the cable through the most appropriate path.

Some of the pulleys are self-adjusting, as the floating platform 100 moves, via the central portion 6 and the bottom portion 8, adapted to change direction.

- Protruding structural arms 12: On the floating platform 100, the external pulleys (first rotating fixture 3) are located farther from the central counterweight 1, further than the circumference of the main structure 400 of the floating platform 100. These protruding structural arms 12 are extensions of a bracket-shaped helmet (or any other type of structure) and are used to clamp the external pulleys (first rotating fixture 3), the internal pulleys 2 (second rotating fixture 2c and optionally third rotating fixture 2d) or the intermediate pulleys (rotation guide 11).

- Crossing sub-line 200c: An anchoring sub-line with the inner pulley (second rotational fixture 2c) beyond the central axis 300 of the floating platform 100, almost directly opposite the corresponding outer pulley.

- Direct sub-line 200d: An anchored sub-line with the inner pulley (third rotational fixture 2d) very close to the outer pulley (first rotational fixture 3). However, the direct sub-line 200d may also not have an inner pulley (third rotational fixture 2d); in this case, the cable orientation is from the outer pulley (first rotational fixture 3) directly to the counterweight 1.

The complete anchoring line 200 is a set of two anchoring sub-lines (a direct sub-line 200d and a cross sub-line 200c) sharing the same bottom weight 4, a portion of the bottom 8 of the anchoring cable and a portion corresponding to the central counterweight 1. Their outer or external pulleys (first rotational fixtures 3) are quite close to each other; usually, these are parallel to the same rotation axis. On platforms using protruding structural arms 12, these external pulleys are suspended from the end of the same protruding structural arm 12. Instead of two external pulleys, it may include a single external pulley with at least two pulleys (one pulley for the direct sub-line 200d and another pulley for the cross sub-line 200c).

- Anchor wires: The conventional anchor wires 200 (described above) are responsible for maintaining the verticality of the floating platform 100. The components are large and can withstand the great stress of anchor cables, especially when the floating platform 100 is used as a support for a wind turbine.

- Shock Absorption Line: Anchor Line 200 with some variations:

One of the pulleys (interchangeably the internal or the external one) is connected via a gearbox (or a hydraulic motor driving a generator) to an electric generator which allows to extract the energy of the movement of the floating platform 100 .

The central part 6 of the anchor cable has a multi-elastic part (its function is a spring) so that it absorbs the change of the length of the anchor cable;

The voltage of the cable is limited by the electrical characteristics of the generator and is much lower than the voltage of the lock wire;

The dimensions of the components (cable diameter, pulleys, supports, etc.) are also smaller, since the cables are subject to lower stresses. In fact, they can be made of other materials that have lower impedance than the locking wire.

- Parallel anchor lines 200: An anchor line 200 whose bases 8 are vertical (in their resting position), as shown in Figures 1 to 6; even if the platform moves, all bases 8 remain parallel.

- Diverging anchor line 200: An anchor line 200 whose bottom 8 is not vertical (one fastened to the seabed 5), but instead is inclined outwards (forming an angle A with respect to the vertical), i.e. the lower end of the anchor line 200 is further from the central counterweight 1 than the outer pulley (Figure 7).

- Group of anchor lines 200: A group of several anchor lines 200 (locking or shock absorbing) sharing a common central counterweight 1. The resulting arrangement must be radial, although each branch may have different dimensions (distance between the centerline axis and the external pulleys). All the internal pulleys of the group must be at the same distance from the central axis 300 of the floating platform 100 (coincident with the vertical direction of the counterweight 1).

A floating platform 100 with a very long geometry can be equipped with several groups of anchor lines 200 acting on the same counterweight 1 (the center line of each group of anchor lines 200 is fastened to a different point of the counterweight 1, which can also be elongated).

On the super-large floating platform 100 , there may be several groups of anchor lines 200 , and each group of anchor lines 200 has its corresponding counterweight 1 .

In all preferred embodiments, as shown in the figures, the anchoring system has only one group of anchoring lines (and therefore only a single counterweight 1).

- Soft Leg Platform (SLP): A floating platform 100, in which the anchoring system proposed in this patent application has been installed. In each complete anchoring line 200, there are two anchoring sub-lines (200d, 200c), and the inner pulleys (second rotating fixture 2c and third rotating fixture 2d) are at the same distance from the central axis 300 of the floating platform 100. Each anchoring line 200 is composed of a direct sub-line 200d and a cross sub-line 200c, and its inner pulleys (second rotating fixture 2c and third rotating fixture 2d) are symmetrically arranged with respect to the vertical central axis 300 passing through the central counterweight 1, as shown in Figures 8 and 9.

- Center well (optional, not shown): a hole that passes vertically through the entire floating platform 100, just below the inner pulley, for the passage of the pendulum (cables and counterweight 1 of the center part 6); if the inner pulley is very far from the vertical position of the center counterweight 1, the center well is not needed.

Most of the components that make up the proposed system have been described above. Other optional components help in the proper functioning of the main components with other components, which helps in the actual implementation on a given platform.

The simplest configuration consists of four locking anchor lines 200, each of which is composed of two sub-lines (a straight line 200d and a cross 200c), each of which includes:

- a bottom weight 4 supported on the seabed 5;

- two rotating pulleys or fixtures (2, 3): an outer pulley (or first rotating fixture 3) and another inner pulley (second rotating fixture 2c); optionally, there may be a second inner pulley (or third rotating fixture 2d for each direct sub-line 200d of the anchoring line 200);

- A central counterweight 1, shared by four anchor lines 200;

- A cable (in each sub-line), connecting the bottom weight 4 and the central counterweight 1, passes through the outer pulley (the first rotating fixture 3) and the inner pulley (the second rotating fixture 2c or the third rotating fixture 2d), defining three parts 6, 7, 8 of the sub-line 200c, 200d with the inner pulley:

The central part 6 of the anchor cable connects the inner pulley (the second rotating fixture 2c or the third rotating fixture 2d) with the central counterweight 1. Its length depends on the vertical position of the central counterweight 1. Optionally, the part of the cable closest to the central counterweight 1 is referred to as the anchor cable adjustment leg, which can be used to adjust the entire length of the cable for uneven bottom or seabed 5 at the point where the floating platform 100 is placed;

The middle portion 7 of the anchored cable connects the inner pulley (the second rotation fixing device 2c or the third rotation fixing device 2d) and the outer pulley (the first rotation fixing device 3), and has a fixed length due to its natural characteristics;

The bottom 8 of the anchored cable is connected to the external pulley (first rotating fixture 3) and the bottom weight 4. Its length depends on the geometry of the platform (i.e. the depth of the seabed 5). Optionally, the bottom 8 can be divided into two parts or sections, attached to the buoy 9. In this way, the installation and maintenance operations of the cable are quite convenient.

Since the three parts 6, 7, 8 are components of the same cable, the sum of their lengths is fixed. The task of the three elements is to avoid rolling and pitching movements of the floating platform 100, allowing horizontal and vertical movements.

If the floating platform 100 moves vertically by a height V, the counterweight moves vertically by a height 2V, but the force acting on the floating platform 100 hardly changes.

If the floating platform 100 moves horizontally by a distance H, the anchor line 200 generates an opposite horizontal force, tending to pull the floating platform 100 back to its original position. The vertical force on the floating platform 100 hardly changes. The counterweight 1 moves slightly upward.

If a bending moment is applied in an attempt to cause the floating platform 100 to rotate in the pitch direction, the tension of the cables of the anchor lines 200 changes to compensate and avoid rotation; if the bending moment increases sufficiently, one of the anchor lines 200 will relax its tension and the floating platform 100 will be held only by the other anchor lines 200. Typically, the platform or central structure 400 of the floating platform 100 will begin to submerge slightly.

With all but one anchor line 200 tension-free, the floating platform 100 may begin to capsize. The capsizing will be reversible or irreversible, depending on the specific geometry of the overall assembly.

The theoretical basis of the present invention is based on a geometric structure, which can be seen in Figure 2.

Each anchor cable can be considered almost inextensible. If we assume that the lengths of the three parts are fixed: T6 (the length of the center part), T7 (the length of the middle part) and T8 (the length of the bottom part), the sum of the lengths of the three parts 6, 7, and 8, T6, T7, and T8, is fixed: T6+T7+T8=constant.

Since the length of the middle portion 7 does not change, T6+T8=constant is also satisfied.

The floating platform 100 has two anchor lines 200 (if a planar movement is assumed, if a three-dimensional movement is considered, at least four anchor lines 200 need to be considered, two-to-two staggered, but the result is the same). If we compare the lengths of the parts of the platform at two different locations:

- Projected case: it has two lines P and Q, each with the three parts mentioned above;

- Any other position: Lines are switched to R and S.

Since each line P, Q, R, S maintains its length;

T6(P) + T8(P) = T6(R) + T8(R) and T6(Q) + T8(Q) = T6(S) + T8(S)

Since T6(P) = T6(Q) and T6(R) = T6(S) (they show the same measurement results).

If we start with two symmetric lines, that is, T8(P) = T8(Q), then T8(R) = T8(S)

In other words, the two external pulleys (the first rotating fixture 3) and the two bottom weights 4 form a "hinged" quadrilateral, whose opposite sides are equal, so no matter where the center of the floating platform 100 is located, the upper side is always parallel to the lower side.

Two anchor lines 200 are sufficient to prevent the floating platform 100 from rotating in a plane, as shown in FIG. 1 or FIG. 2. For example, if the longitudinal roll angle is to be avoided, two anchor lines 200 are required in the longitudinal section, with one outer pulley at the fore and one outer pulley at the stern, with two inner pulleys in between (the middle of the anchor cables do not need to be the same). If the transverse roll angle is to be avoided, two anchor lines 200 are required in the transverse section of the waves,

4 and 5 show schematic diagrams of a complete anchoring line 200 formed by a direct sub-line 200d and a cross sub-line 200c, presented in the position of the design case floating platform 100 (FIG. 4) and in any other position (FIG. 5).

The two inner pulleys (2d: directly and 2c: crossed) are at the same distance from the central axis 300 of the floating platform 100 (in reality, the pulley axes are in different directions, but this makes the middle part 7 appear from the symmetry point: the point where the cable and the pulleys touch). In the design situation (Figure 4), the lengths of the two sub-lines 200c, 200d are different, but the central parts 6d, 6c are equal, so the central counterweight 1 is at a position corresponding to the central axis 300 of the floating platform 100.

When the floating platform 100 is moved (FIG. 5), the lengths of the bottom parts 8d and 8c change, but they remain equal to each other. The lengths of the middle parts 7d and 7c do not change (the pulleys move firmly with the platform). Since the total length of each sub-line 200c, 200d does not change, the central parts 6d and 6c also change their lengths, but they remain equal to each other, i.e. the central counterweight 1 moves vertically, but remains in a position corresponding to the central axis 300 of the floating platform 100. In this way, the pendulum motion of the counterweight 1 in the original version of the anchoring system can be completely eliminated.

When two complete anchoring lines 200 are combined (each with direct sub-lines 200d and cross sub-lines 200c), the same reasoning applies, when the lines are centered (in the art, a platform with a centerline passing through a center well), the bottom 8 of each complete anchoring line 200 remains equal to each other, regardless of the position of the floating platform 100. In this case, the anchoring system (with direct sub-lines 200d and cross sub-lines 200c) behaves as if all sub-lines were centered.

The operation diagram of the system with direct strands 200d and cross strands 200c can be seen in Figure 3. If there were only central strands, the diagram would be the same, the angle β between the central portions 6 would be zero (ie they would be perpendicular).

When external forces (wind, waves or ocean currents) act on the floating platform 100, they generate a bending moment Mf and a force Fx, pushing the floating platform 100 to the position shown in the figure.

In other respects, in windward (F1) and leeward (F2), the central counterweight 1 has a net weight (dry weight minus hydrostatic thrust), and the tension of the two cables of the anchor line 200 generates two forces. If the inertial forces caused by the movement of the floating platform 100 and the counterweight 1 are neglected, the forces on the direct and cross cables on each side are equal:

F1c = F1d = F1/2, and F2c = F2d = F2/2

Because of the balance of forces acting on the counterweight, it satisfies:

(F1 + F2) x cosine (β) = P

These forces are transmitted to the bottom weight 4 via the cables.

In order for the floating platform 100 to achieve balance, the two forces F1 and F2 applied to the bottom 8 must fully compensate for the bending moment Mf of the external force.

(F1-F2) x external pulley distance x cosine (α) = Mf

Since the cables do not work in compression, when the force F2 is positive, the floating platform 100 will remain horizontal and then begin to tilt toward the leeward.

On the other hand, horizontal force balance requires:

FH = F1 x sine (α) + F2 x sine (α) = P x sine (α) / cosine (β) = Fx

According to a variant of the anchoring system, in which the anchoring lines 200 are divergent, the pitch angle imposed by the external forces acting on the floating platform 100 can be corrected. The elasticity of the anchoring lines 200 means that when the floating platform 100 is subjected to external forces, the windward cables are lengthened and the leeward cables are shortened: the result of these deformations of the floating platform 100 is a small pitch angle in the leeward direction.

The variation shown consists of a given angle of the bottom 8 of the anchoring line 200 , separating the vertical anchoring point of the outer pulley (first rotational fixture 3 ), as shown in FIG. 7 .

When the floating platform 100 moves horizontally due to wind drag, the deck of the floating platform 100 does not remain horizontal, and instead turns to face the wind. This rotation angle is geometrically related to the angle of the bottom 8 and the depth of the seabed 5, and is roughly proportional to the magnitude of the horizontal movement. By adjusting the angle of the bottom 8 of the anchor line 200, and because of the elasticity of the anchor line 200, the longitudinal roll of the floating platform 100 can be accurately eliminated regardless of the horizontal force applied (until any line is deployed).

By way of example, three alternatives are presented below for securing the cable to the bottom 8 on the seabed 5. In all of them, an intermediate buoy 9 can be introduced into the bottom 8 (at a similar depth to the counterweight 1, in its designed position), connecting the cable or chain to the anchors on the seabed 5.

In this way, the final installation is very simple, since it is sufficient to grab the cables at the buoy 9, and the floating platform 100 is fully operational.

- A mooring ring can be used, for example, by means of a solid structure that links all the bottom weights 4 together, including fastening points for the cables at appropriate locations. This structure consists of several ballast tanks, initially empty, giving the assembly a slight positive buoyancy. This structure is moved to the wind farm and sunk in the place where the floating platform 100 will be installed. This operation does not require great precision, since determining the anchoring points will correct the position regardless of the position of the ring on the seabed 5. When the floating platform 100 is placed in the installation location, it is sufficient to fasten the cables on the anchor blocks for the operation of the floating platform 100.

- Foundation piles inserted into the seabed 5 can be used. This system is copied from the foundations of TLP type platforms. The location of the seabed 5 is prepared and foundation piles containing anchoring points for anchoring lines 200 are inserted. Essentially different from the TLP system, the tensile stresses that the anchoring system of the invention must withstand are much lower than for a TLP platform, in fact, for equal installation forces, the stresses are of the order of one fifth or less. This makes the preparation of the anchoring ground much cheaper and easier.

- It is possible to use bottom weights 4 previously located on the seabed 5. Due to the low voltage of the cables, individual bottom weights 4 can be used, precisely positioned on the seabed 5, on a pre-prepared seafront promenade. This is an intermediate solution between anchor rings (very large structures but easy to place) and the use of foundation piles (requiring considerable ground preparation and precise placement of back weights 4).

Comparison of the anchoring system of the present invention with the TLP platform (tension leg platform):

Obviously, the floating platform 100 with the TLP type anchoring system and the floating platform 100 with the anchoring system of the present invention serve the same purpose. Their goal is to overcome the pitch/roll motion of the floating platform 100. However, the operating principles of the two are fundamentally different, and their motion and dynamic characteristics are also different, as can be seen in the following table: characteristic TLP Platform SLP Platform (Anchoring System of the Invention) Upright position Almost fixed, moves in an arc of a circle, with the anchor weight centered Complete freedom within the design range (range depends on the length of the center) Pan/tilt angle Theoretically, it is zero, depending on the elasticity of the anchor wire. Based on the bottom: - Vertical: Theoretically invalid - Divergence: Reverse control or zero Cable design voltage very high Medium, less than 1/5 TLP platform voltage comparable to traditional anchoring Average voltage of the cable in static state Grows with the wave's height and horizontal movement The situation is almost constant at any sea level and the weight is not too close to the platform Possibility of loss of cable tension in the lee Because of the external bending moment, because of the low tide, because of the very large waves Because of the external bending moment and because of the very large waves The bend in the tower's foundation Some are taller than land-based windmills. Possibly lower than onshore windmills (divergent lines) External presentation Very tall and elongated platform Low height, flat platform (any shape) Environmental shock High environmental impact, especially at low tide In any case, reduce environmental impact Geometric requirements of the platform Small floating area no other related No shape Moving parts without Almost the entire anchoring system Transport to the operating location Very complex, requiring special vessels Very simple, just a traditional tugboat install Very complex, requires very precise anchoring Very simple, does not require grounding, is almost autonomous in its installation Operation position change Almost impossible Very simple, all you need is a tugboat for transport

A diagrammatic description and discussion of the patent application follows.

In all the illustrations, the depth to the seabed 5 is reduced to make the images more balanced and easier to interpret. If the seabed 5 were quite close, it would not be worth using the floating platforms 100, since it would be better if they were supported directly on the seabed 5. In a real project, the counterweight 1 would also be proportionally deeper than shown in the illustrations.

FIG1 shows a basic diagram of anchoring anchor lines 200 (these prevent rotational movement of the floating platform 100). This type of installation consists of a floating platform 100 floating on the sea, providing two or more anchor lines 200 (at least two anchor lines 200 when you only need to overcome rotational movement in one direction, such as longitudinal roll; at least four anchor lines 200 when you want to overcome longitudinal and lateral roll at the same time), each anchor line 200 is composed of at least two sub-lines 200d, 200c, each anchor line 200 is composed of It is composed of one (or two) inner pulleys (second rotating fixture 2c and third rotating fixture 2d), and outer pulleys (first rotating fixture 3), supported by a cable or anchor line 200 composed of three parts, the three parts are the bottom 8 to the bottom weight 4 resting on the seabed 5, another central part 6 fixed to the central counterweight 1, and the middle part 7 connecting the other two parts 8 and 6. The central counterweight 1 is shared by all anchor lines 200. The bottom 8 can be divided into two parts, which are attached to the middle buoy 9; in this case, the lower part (first part) of this bottom 8 is shared by all sub-lines, suspended from the same protruding structural arm 12. Two complete anchor lines 200 are simultaneously shown in FIG. 1 , one (the one on the right) using a solid line and the other (the one on the left) using a dashed line.

FIG. 2 shows a schematic diagram of the geometric principle, adjusting the length of each portion 6, 7, 8 of the anchoring line 200, demonstrating that the floating platform 100 always moves parallel to its initial position. The schematic diagram corresponds to the central anchoring subline (floating platform including a central well) of an anchoring system of the state of the art (such as Spanish patent No. ES 2629867 A2). This diagram provides a basis for facilitating the operation compensation of the anchoring system of the invention.

FIG3 is a schematic diagram of the dynamic principle, when the floating platform 100 is subjected to a force Fx and a bending moment Mf from external forces (wind, waves or currents), acting on the anchor lines 200. The sum of the tensions of all anchor lines 200 is always fixed (equal to the apparent weight of the center counterweight 1, divided by the cosine of the angle β between the center part 6 and the center axis 300; the difference between the tensions of the anchor lines 200 is proportional to the cosine of the bending moment Mf and the horizontal force FH, which can support the floating platform 100, is proportional to the sine of the angle α between the bottom 8 of the anchor line 200 and the vertical direction. If the cable of the bottom 8 of the leeward anchor line 200 becomes loose, the platform loses its horizontal position (swaying and rolling movements are obvious).

Figures 4 and 5 show basic diagrams of the anchoring system, similar to Figure 1, with the middle buoy 9 removed, so that the bottoms 8d, 8c of the direct sub-line 200d and the cross sub-line 200c reach the bottom weight 4 on the seabed 5. Figure 4 shows the floating platform 100 in its static position, and Figure 5 corresponds to the floating platform 100 changing its position (horizontally and vertically) due to the influence of wind and waves.

Fig. 6 shows the operation of an anchoring system with parallel anchoring lines 200, the bottom 8 being vertical in its rest position (dashed line). When the floating platform 100 moves (solid line), the cover of the floating platform 100 always remains horizontal.

FIG. 7 shows an operation diagram of an anchoring system with divergent anchoring lines 200, the base 8 does not descend vertically to the seabed 5, but the working platform forms an angle A with respect to the vertical. When the floating platform 100 moves horizontally, it tilts toward the wind. In a first path, it rotates around the intersection of the two bases 8. If the floating platform 100 is a support for an offshore wind turbine, with a tower 13 and a wind turbine cabin 14, the weight of the cabin 14 is a straight-axis structure (because the inclination of the tower 13 can correctly compensate for the thrust of the wind on the blades of the rotor, thereby reducing the entire bending moment of the tower 13 of the wind turbine (so the bending moment is transmitted to the floating platform 100 through the tower 13).

An example of an anchoring system comprises four anchoring lines 200 as shown in Figures 8 and 9. This version of the anchoring system is applied to a floating platform 100 having an even number of protruding structural arms 12. In this schematic diagram, the inner pulley (third rotating fixture 2d) of the direct sub-line 200d is eliminated so that the outer pulley (first rotating fixture 3) also performs the function of the inner pulley, and of course the middle part 7 of the direct sub-line 200d is also eliminated. The inner pulley (second rotating fixture 2c of the cross sub-line 200c) appears close to the outer pulley (first rotating fixture 3), but this is an optical effect of the cross sub-line 200c of the pulley corresponding to the other protruding structural arm 12 (the opposite arm). Also shown in the middle is the middle pulley (the rotating guide device 11 of the cross sub-line 200c, which shifts the middle part 7 of the cross sub-line 200c so that the same part of the vertical line will not cross (at the "display intersection", this part passes at different heights).

Figures 10 and 12 correspond to the installation phase of a floating platform 100 stabilized in a ballasted state (presented in the illustration of a floating platform 100 with four projecting structural arms 12, although it is valid for any such platform). More particularly:

- In Figure 10, the bottom anchors ready to receive the floating platform 100 can be seen, the anchor lines 200 and the lower part (first part) of the bottom 8 of the bottom weight 4 with the intermediate buoy 9. The floating platform 100 in its loaded state has a buoyancy element 500, including a submerged area 15 and another surfaced area 16 on the buoyancy lines 21, and the central counterweight 1 is centrally located below the floating platform 100. The anchor lines 200 are connected to the counterweight 1, but not to the buoy 9.

- Figure 11 shows the upper part (second part) of the bottom 8 of the anchor line 200, connected to the buoy 9, and the counterweight 1 partially submerged, pulling the cable tight and sinking to its designed position. The floating platform 100 is somewhat deeper than the ballasted state, but has not yet reached the operating state (where the waterline 21 is located corresponding to the operating draft 22). The splines 600 of the floating platform 100 are completely surfaced and the floating platform 100 still maintains its stability.

- Figure 12 shows the floating platform fully installed, the submerged chamber of the counterweight 1 has been submerged and the cables are working at their normal voltage. The floating platform 100 is at its operating draft of 22, ready to start service.

Figures 13, 14 and 15 correspond to the first embodiment of the invention. These figures show a floating platform 100 used as a support for an offshore wind turbine with four anchor lines 200, which is stable in a loaded state. The floating platform 100 has two main loaded states: a loaded state, in which the buoyancy line 21 passes through the middle point of the floating element 500 (dividing it into two parts: a submerged zone 15 and another surfaced or surfaced zone 16, which is submerged only in the operating state), and in the operating state, the buoyancy line 21 passes through the middle point of the radial 600 (divided into a submerged radial zone 17 in the operating state, and another never submerged zone 18), already corresponding to the working draft 22. The spokes 600 are attached to the platform in an axis, in this case, comprising a structural ring 19, with eight rectangular faces (four spokes 600 meet four protruding structural arms 12) and eight other trapezoidal faces connecting the rectangular faces. The four protruding structural arms 12 serve as supports for the outer pulley (first rotary fixture 3) and the inner pulley (only the second rotary fixture 2c presenting the anchor line 200 and no third rotary fixture 2d). On the structural ring 19, there is a small truncated superstructure 20 for the electronic devices of the floating platform 100, and above it is the tower 13 supporting the wind turbine.

Figures 13, 14 and 15 show three views of a floating platform 100 with direct sub-lines 200d and cross sub-lines 200c. Figure 13 shows a side view (side) of the assembly, aligning the spokes 600 or legs of the floating platform 100, keeping the floating elements 500 submerged. Figure 15 shows a front view of the assembly, aligning the protruding structural arms 12 (rotated 45 degrees relative to the spokes 600) for supporting external pulleys, arranged on the bisector between the spokes 600. Figure 15 shows a first arm 12a and a second arm 12b, belonging to a pair of protruding structural arms 12 located in the same plane. Figure 14 shows a three-dimensional (3D) view of the assembly.

The projecting structure arm 12 includes a first end 121 attached to the platform or main structure 400 of the floating platform 100 , and a second end 122 projecting outward from the floating platform 100 .

Figures 16, 17 and 18 correspond to the second embodiment of the invention. These figures show a floating platform 100 used as a support for an offshore wind turbine, which is not stable under pressure, and has four anchor lines 200, with direct sub-lines 200d and cross sub-lines 200c, and the middle part 7 of the anchor lines 200 includes the steering of the middle pulley (rotation guide device 11). In this case, the pulley is arranged horizontally and the steering cable is outward to prevent the upper structure 20 from supporting the tower 13 of the wind turbine. The platform or main structure 400 is as simple as possible, a simple vertical axis cylinder, divided (conceptually) into three parts: a submerged area 15, which is always submerged (even under pressure), another floating or surfaced area 16, which is submerged only under operation. There is also a never submerged area 18, which is a part of the platform or main structure 400, which is surfaced under any load (similar to the top of the beam 600 of the floating platform 100 of the first embodiment). Similar to the floating platform 100 of the first embodiment shown in Figures 13 to 15, in the second embodiment, the floating platform 100 also includes four protruding structural arms 12, and a small superstructure 20 on the platform for supporting the tower 13 of the wind turbine.

16, 17 and 18 show three views of the floating platform 100 with four protruding structural arms 12, which are a side view, a three-dimensional view and a front view (aligned with the protruding structural arms 12 of the floating platform 100).

Figures 19, 20 and 21 correspond to a third embodiment of the invention, in which a floating platform 100 is shown used as a support for an offshore wind turbine and is stable under pressure. According to this third embodiment, the hull or main structure 400 of the floating platform has a ring-shaped geometry, forming a floating ring 700. It has a central well, although it is not used for this (not for the passage of counterweight cables). Four protruding structural arms 12 rise from the submerged hull or main structure 400. Figure 19 is a front view of the assembly (aligning the protruding pulleys with the structural arms 12). Figure 21 is a side view rotated 45∘ (turning according to the bisector of the arm). Figure 20 is a three-dimensional view of the assembly.

Although the proposed anchoring system is effective for any floating platform 100 (intended to support any type of structure), the present invention is particularly directed to two specific applications, for the support of offshore wind turbines and for offshore leisure platforms. With regard to the purpose of the proposed patent (anchoring system), the main difference between the two applications is that in the deck area of the floating platform 100, the external pulleys are suspended from radially arranged protruding structural arms 12, which protrude a considerable distance from the deck of the floating platform 100, and in platforms designed for marine leisure, the external pulleys are suspended from very short arms protruding from the main deck of the platform.

The anchoring system according to the first embodiment of the present invention includes the following elements:

- Four anchor lines 200, each of which is formed by two anchoring sub-lines 200c, 200d, each sub-line 200d, 200c consisting of an anchoring cable suspended from an external pulley (first rotating fixture 3), respectively suspended from a protruding structural arm 12, used as a support for the anchor line 200. The bottom 8 of the anchoring cables of all sub-lines (same anchor line/arm) bears the bottom weight 4 directly or through the intermediate buoy 9 and the common part (the first part or lower part of the bottom 8). The central part 6 of all anchor lines 200 bears the central counterweight 1 common to all anchor lines 200.

- Floating platform 100: the platform or main structure 400 is attached to four vertically axial cylindrical floaters or floating elements 500, arranged at the vertices of a quadrilateral and spaced sufficiently apart to allow the central counterweight 1 to fit in the center of the platform with the necessary clearance. The floating element 500 is attached to the platform or main structure 400 of the floating platform 100 by four "leg" devices or tilting beams 600, which coincide with the reinforcing structural ring 19 located below the superstructure 20 of the floating platform 100 and above the operating draft 22. Connected to this structural ring 19 are four protruding structural arms 12, which grasp the pulleys (external pulley (first rotating fixture 3) and internal pulleys (second rotating fixture 2c and any third rotating fixture 2d) of the anchor line 200. In this reinforced structural ring 19, there is an upper structure 20 supporting the wind turbine tower 13. In the loaded state, the waterline 21 is approximately halfway up the floating element 500, and the floating platform 100 itself is stable. In this operating situation, the operating draft 22 is halfway up the beam 600, and the floating element 500 is completely submerged.

- Central weight 1: A cylindrical tank with vertical axis, weighted but with volume, so that it is completely hollow, it has a positive buoyancy of the order of 10% of its volume. The interior is divided into several ballast compartments or flooding chambers, which can be filled or empty independently. One of the flooding chambers is flooded, with a slight negative buoyancy. On its top plate, there are four pairs of anchors to secure the ends of the central part 6 of all the sub-lines 200c, 200d of the anchoring line 200.

- Wind turbine: consists of a wind turbine tower 13, supported on the main structure 400 of the floating platform 100 (on the upper structure 20 of the reinforced structural ring 19), fastened to the upper part of the projecting structural arms 12 and the beams 600. The tower 13 holds the cabin 14, located at the location of the wind turbine. It is a commercial component, so it will not be described in detail.

- The submerged floating element 500 is accessible via a staircase inside the leg or spoke 600 of the floating platform 100 (for maintaining operation). This leg or spoke 600 is accessible via a watertight door located in the corresponding rectangular face of the reinforcing structure ring 19. This floating platform 100 has two operating modes:

In the transport (or ballasted) condition, all submerged chambers are hollow and all anchor lines 200 are collected and free floating, with no excessive restraint beyond the cables connected to the tugboat. In this case, the floating platform 100 is self-stabilizing.

In the operational (or design) situation, any ballast compartment or flooded chamber is partially filled to obtain the platform floating at its operational draft 22 or design draft. The floating platform 100 is connected to the center weight 1 via the center portion 6 of all anchor lines 200, and is connected to the seabed 5 via the bottom 8 of the anchor lines 200. In this situation, the floating platform 100 is not stable by itself and relies solely on the stability provided by the anchor lines 200.

In FIGS. 13 to 15 , three views of a first embodiment (whose main elements are identified) can be seen, with a proposed anchoring system.

In the anchoring system, according to the second embodiment of the present invention, unlike the first embodiment, the floating platform 100 is unstable under pressure, so anchoring rings are required to stabilize the platform during transportation from the shipyard to the closure site.

The main structure 400 of the floating platform 100 comprises a vertical axis cylinder, conceptually divided into three parts or zones: a submerged zone 15, in any load situation, in the deepest part of the cylinder; a surfaced or surfaced zone 16 (intermediate zone), surfaced in pressure situations and submerged in operational situations, and another never submerged zone 18 (superstructure), which is always above the waterline 21. Furthermore, the floating platform 100 comprises four radially arranged projecting structural arms 12 (of course with the same number of anchor lines 200). The main structure 400 comprises a small superstructure 20 for the electronic equipment of the wind turbine and a tower 13 which also serves to support the wind turbine.

In this second embodiment, the floating platform 100 is the simplest and most economical (among the three proposed embodiments), but has a different hydrodynamic behavior compared to the other two embodiments, because it has more buoyancy area, it tends to move with the waves, and therefore the vertical movement is greater than the other embodiments; relatively speaking, it can extract more energy from the movement of the waves, and the wave profile is maintained closely to its designed buoyancy (operating draft 22), so it needs a lower height out of the water than the other platforms.

In FIGS. 16 to 18 , three views of a second embodiment can be seen (whose main elements have been identified), the proposed anchoring system having an intermediate pulley (rotating guide 11 ) horizontally in each intermediate portion 7 of the anchoring cable, serving to separate the cable from the superstructure 20 .

The anchoring system according to the third embodiment of the present invention is stable under load and includes the following features:

- It has four radially arranged projecting structural arms 12 with anchoring lines 200;

- The reinforcing structure ring 19 is located higher than in other embodiments, and the upper structure 20 is smaller (lower) than in other embodiments, and serves as a connecting element to the four legs or spokes 600, some of which are longer than in other embodiments.

- The main structure 400 comprises a ring-shaped geometric structure forming a floating ring 700 including at least one submerged chamber.

Three views of a third embodiment (whose main elements have been identified) can be seen in Figures 19 to 21. The direct strand 200d does not have an inner pulley (third rotation fixture 2d) because the outer pulley (first rotation fixture 3) performs two functions (inner and outer, providing space), and the cross strand 200c uses a vertical middle pulley (rotation guide 11) for redirecting the cable.

As can be seen in the figure, the reinforcing structure ring 19 is raised so that the cables of the middle part 7 of the cross strand 200c pass under the upper structure 20 and between the legs or spokes 600 of the floating platform 100. If an intermediate pulley is included in this part to deflect the cables downward, the reinforcing structure ring 19 can occupy a low position.

As mentioned above, in the anchoring system of the present invention, each anchoring line 200 has a direct sub-line 200d and a cross sub-line 200c, wherein the inner pulley of the cross sub-line 200c is located directly opposite to the inner pulley of the direct sub-line 200d. This arrangement acts on even-numbered anchoring lines 200 (and the protruding structural arm 12), and also causes the inner pulley of the direct sub-line 200d of the first anchoring line 200 on the protruding structural arm 12 to be close to the inner pulley of the cross sub-line 200c of the second directly opposite anchoring line 200, although on different sides of the protruding structural arm 12.

On a floating platform 100 for a wind turbine, a projecting structural arm 12 is used to grasp the pulleys, with two outer pulleys at each head, including a direct inner pulley (which may be omitted), and a crossed inner pulley directly opposite the anchor line.

The two protrusions of this anchoring system have four protruding structural arms 12, as can be seen in FIGS. 8 and 9; however, the floating platform 100 may have a different even number of protruding structural arms 12.

In this type of anchoring, the middle part 7 of the cross sub-wires 200c of the anchoring wires 200 can pass on the other side of the floating platform 100, very close to the central axis of symmetry 300; therefore, some holes for these cables can be made in the platform body or superstructure 20. An alternative method can be used in the above example, using an intermediate pulley (rotating guide device 11) to deflect these cables and pass them in the superstructure 20 of the floating platform 100 (or outside on its side).

Depending on the geometry of the floating platform 100, the anchoring system may require some elements to facilitate its correct operation, which have been introduced in the previous section. Some of these elements can be seen in Figures 8 to 11, while others are common elements of shipbuilding and are not shown in the figures. These include, but are not limited to:

- Intermediate pulley for supporting the middle part 7 (rotating guide 11): The middle part 7 is shaped like a suspension cable, supported on inner and outer pulleys. The suspension cable changes length depending on the tension to which the cable is subjected. This phenomenon translates (if the distance between the pulleys is greater) into the movement of the cable in this part, if it is more elastic than usual, and will affect the operating principle of the system. To avoid this, the intermediate supporting pulley (rotating guide 11) can be placed in this part (reducing the distance between the supports and therefore drastically reducing the arrow corresponding to the suspension cable), so that the cable behaves almost straight and the cable regains its original rigidity. It also serves for the steering of the middle part 7 (avoiding structural obstructions).

- External pulley support arms (projecting structural arms 12): used to support wind turbines on floating platforms 100, the diameter of which is much smaller than the optimal distance for placing external pulleys. The projecting directional structural arms 12 then need to project from the main structure 400 of the floating platform 100 and be suspended by external pulleys. Each projecting structural arm 12 can be a lattice structure (the element is exposed to the weather), or a closed structure (the element is protected from the weather); the choice of one or the other type will depend on the principles of each specific design.

The floating platform 100 serves as a support for a wind turbine having several characteristics, among others:

- The floating platform 100 does not require a large deck surface and can support the weight of the wind turbine and the tower 13 with a small buoyancy;

- The main forces acting on the system are taken into account, mainly the aerodynamic thrust of the wind on the blades of the wind turbine rotor.

- The force of the wind exerts a very large bending moment on the foundation of Tower 13.

If the anchor line 200 is not vertical (as shown in FIG. 13 ) by design, but slightly diverges (as shown in FIG. 14 ), when the floating platform 100 is dragged by the wind, the windward pulley rises relative to the windward; as a result, the floating platform 100 has a pitch angle against the wind force. This pitch angle is proportional to the horizontal displacement of the floating platform 100 and is only sensitive to vertical displacement.

This angle causes the weight Q of the cabin 14 to have an axial component, opposite to the force of the wind on the rotor blades, which is proportional to the angle of rotation, which in turn is proportional to the horizontal movement of the floating platform 100. If these proportionality constants are properly synchronized, the axial component of the weight of the cabin 14 can be controlled to correctly cancel the wind force regardless of the wind speed.

In this way, the bending moment on the foundation of the tower 13 due to the wind can be completely eliminated. Because the waves still cause forces and movements, but only lower forces and movements. Therefore:

- The tower 13 can be lightweight, with thinner thickness of its structural elements;

- reduced forces acting on the load bearings of cabin 14;

- The anchoring load is reduced and the structure of the floating platform 100 can be lightweight (and inexpensive to build).

On a floating platform 100 dedicated to marine leisure, the external force that has the greatest impact on passenger comfort is the impact of waves. The anchoring system of the present invention can eliminate the rotational motion of the floating platform 100. Vertical movement has a small impact (especially if a semi-submerged floating platform 100 is used), but the horizontal movement of waves still has an impact. Large waves can produce significant acceleration (up to 1.5m/ ^s2 ).

In some applications, an anchor system with diverging anchor lines 200 may be used to produce a longitudinal roll that is opposite to the horizontal movement. This longitudinal roll can produce a longitudinal acceleration that is opposite to the acceleration of the horizontal displacement, so that the resulting acceleration is lower than if the floating platform 100 moves without longitudinal roll; this improves the comfort of people on the deck.

The ground analog of this horizontal movement and the reverse pitch can be a swing or hammock action, with large movements or rotations, but without the feeling of acceleration. In fact, the acceleration remains perpendicular to the surface of the deck of the floating platform 100 (vertical to the seat surface, in the case of a swing).

The operation diagram may be similar to that shown in FIG. 7 , but the difference in angle A is somewhat greater than that in this diagram.

The difficulty is that the elimination of the longitudinal acceleration can only be achieved for a relatively small range of waves, for example, waves are eliminated between 8 and 10 seconds; then the problem turns to those periods, which have the most wave-like period. These turns are based on:

- The geometry of the floating platform 100, its stability and its inertia;

- The geometric pattern of the anchor wire 200, and its elastic properties.

The cable of the anchor line 200 is quite long, measuring at least the draft in the operating area, plus the length of the protruding structural arm 12 (usually between 30 meters and 40 meters), plus twice the height between the pulley and the sea surface, plus the maximum vertical movement of the floating platform 100 (maximum tide height + wave height), plus 20% of the draft in the sea in the installation area, plus a margin deemed convenient.

In some applications, the base 8 does not reach the seabed 5 or ocean floor, but is secured in place to an intermediate buoy 9 relatively close to the surface, which is anchored to the seabed 5 by chains or cables, so that only the upper portion of the cable, which is most subject to wear (and which is also most accessible), has been altered.

The length of the detachable cable must be such that with the maximum foreseeable movement of the floating platform 100, the buoy 9 never approaches the external pulley (first rotational fixture 3); if it does, a major failure will occur. The material of the anchoring line 200 can be any material suitable for these applications, including but not limited to:

- Litten cables: no twisting is possible, as the tension of the rope (against the edges of the vertical ridges) prevents yaw rotation of the floating platform 100.

- Cables of synthetic or textile materials;

- Connecting chain: Ideal for the middle part 7 (and the upper part of the other two parts 6, 8) of the floating platform 100, used as a support for the wind turbine, because it allows toothed pulleys (on the damping line) and has a relatively small turning radius. Its disadvantage is that it is relatively noisy. It is not recommended for use in leisure equipment and must be very well sound-insulated. On the floating platform 100 used for marine leisure, the middle part 7 and the upper part of the other two parts 6, 8 must be textile material, because the waves move continuously, which is quieter than the connecting chain (which will cause noise problems in structure).

One of the advantages of the anchoring system of the present invention is the ease of transporting, installing and uninstalling a platform using the anchoring system.

The installation procedure of the floating platform 100 is described in detail as follows.

Under ballasted conditions, the submerged floating elements 500 of the platform float at half height, providing full or partial stability to the floating platform 100 that needs to be transported. The presence of buoyancy retention (the emergence of the floating elements 500 or the embodiment of the emergence zone 16) allows the floating platform 100 to always remain stable during transportation despite the swaying motions caused by the waves.

As described above, in the case of the second embodiment of the anchoring system, anchoring to the anchoring ring is also required to ensure the stability of the floating platform 100 during transportation under load.

Before moving the floating platform 100, the bottom anchors of the anchoring lines 200 are prepared. To do this, bottom weights 4 are placed in their place, which can be of any type:

- Anchored to the ground by means of piles;

- Individual bottom weight 4, located in the flat seabed 5 area;

- a mooring ring, provided on the seabed 5 by any method.

In these bottom weights 4, the common part (first part or lower part) of the bottom 8 of the anchor line 200, in turn, ensures that the middle buoy 9 is fastened or fixed. The buoys 9 are of equal height so that they are all at the same depth and at the same distance from the central axis 300 of the floating platform 100.

This can be done while building a platform.

To transport the floating platform 100, a tugboat is sufficient to tow the floating platform 100 and the counterweight 1 to the wind farm. Alternatively, the counterweight 1 can be placed just below the floating platform 100 (slightly caught by the central part 6 of the sub-lines 200c, 200d of the anchoring lines 200) and towed together. During transportation, the ballast compartment or submerged chamber of all floating platforms 100 and counterweight 1 remains completely hollow. In this case, the counterweight 1 has a slightly positive buoyancy and a small height above the water relative to its support.

The first stage of installation is very simple, just place the floating platform 100 on top of the anchor, with the counterweight 1 under the center of the floating platform 100, as shown in Figure 10. At this stage, there is no need to adopt any external stabilization system, because both the floating platform 100 and the counterweight 1 are stable by themselves.

Next, the upper part (second part) of the bottom 8 of the anchoring line 200 is fastened to the middle buoy 9. The cables are prepared to have the length in the operational situation so that they will be tension-free when hooked (in this case with geometrically excess cables). To tighten them, the floating platform 100 is moved slightly from the vertical position to the anchors (with a tugboat transporting it), or the wind allows to tow the floating platform 100 sideways until these cables are slightly tightened.

Fill one of the tanks or flooding chambers of the counterweight 1 so that it has a slight negative buoyancy. The counterweight 1 begins to submerge, and the tension of the cable returns the floating platform 100 to the position on the bottom anchor. Place the floating platform 100 and continue to fill the ballast tank or flooding chamber of the counterweight 1; as a result, the floating platform 100 gradually sinks by increasing the weight drag of the center counterweight 1. The floating platform 100 at this stage is shown in Figure 11:

- Counterweight 1 gradually submerges, increasing the net weight;

- The cables are generally taut and provide the floating platform 100 with increased stability;

- The floating platform 100 gradually sinks, but retains all initial stability, because the buoyancy element 500 has not yet completely sunk. The waterline 21 rises from ballast buoyancy to operational buoyancy (operating draft 22).

There is a period of time when the floating platform 100 sinks until the floater or floating element 500 is completely submerged. At that time, the stability of the floating platform 100 is almost gone (or drastically reduced). This is not a problem, because the tension of the cables has reached more than 50% of their nominal tension and can provide the floating platform 100 with its required stability.

When all the ballast tanks or flooded chambers of the counterweight 1 are completely filled with water, the floating platform 100 is almost operational, usually it floats slightly higher than the designed floating position (as it must have a considerable safety margin for its buoyancy). At this moment, it is enough to introduce some ballast water into one of the tanks, as it is planned in its operational situation, so that the platform floats correctly.

The assembled appearance is shown in Figure 12. At this moment, the only thing missing is to electrically connect the generator to the wind farm transformer so that the wind turbine can operate normally.

To dismantle the floating platform 100, just follow the reverse procedure, that is:

- disconnecting the wind turbine's electronic circuits from the wind farm's electricity grid;

- emptying the ballast compensation chamber of the floating platform 100 (i.e. emptying one of the submerged chambers of the floating element 500);

- Gradually empty the ballast compartment (at least one flooding compartment) from ballast 1.

When this chamber (one of the submerged chambers of the floating element 500) is emptied, the floating platform 100 begins to rise (and the counterweight 1 does the same). When the floating element 500 reaches the sea surface, the floating platform 100 regains full stability. When the cable begins to loosen tension, the floating platform 100 will be towed sideways by the wind until the counterweight 1 reaches the sea surface.

When the ballast compartment (flood chamber) of the counterweight 1 is completely emptied (and the counterweight 1 has sufficient positive buoyancy), the bottom 8 of the intermediate buoy 9 is released and the floating platform 100 can be moved to another location (or to a port for periodic maintenance operations).

Therefore, one object of the present invention is that the anchoring system for the offshore floating platform 100 is preferably formed by four or six anchoring lines 200, which are radially arranged around the common point 10 of the floating platform 100, and each anchoring line 200 is formed by two anchoring sub-lines 200c, 200d, which may include the following elements:

- an inner pulley 2 (second rotational fixing means 2c, and optionally a third rotational fixing means 2d), and another outer pulley (first rotational fixing means 3), located at the top of the anchoring line 200;

- The central counterweight 1 is common to all anchor lines 200, is located below the intersection of all anchor lines 200, and has several ballast compartments or flooded chambers, so that when the ballast compartments of the central counterweight 1 are empty, it has a small positive buoyancy (e.g. less than 20% of the total volume of the counterweight 1), and when all the ballast compartments of the central counterweight 1 are flooded, it has a large apparent (net) weight (e.g. greater than 15% of the total displacement of the floating platform 100);

- The floatation ring 700 or several floatation elements 500, have several ballast compartments or flooding chambers, so that when the ballast compartments of the floatation ring 700 are empty, they have a small positive buoyancy (less than 20% of the total volume of the floatation ring), and when the ballast compartments of the floatation ring 700 are fully flooded, they have a very large and significant weight (greater than 15% of the total displacement of the floating platform 100).

- The anchor ring is common to all anchor lines 200 or to a plurality of backweights 4 (for each anchor line 200). In operation, the anchor ring rests on the seabed 5, performing the function of a conventional ship anchor, preventing the floating platform 100 from being dragged by wind, current or waves. In certain applications, it can be replaced by several conventional anchors on the seabed 5 (foundation piles, suction anchors, etc.), to which the cables of the anchoring system are fastened.

- The anchor cable connects the central weight 1 to the anchor ring (or to each bottom weight 4 or anchor anchor), and rests on the inner pulley 2 and the outer pulley (first rotational fixture 3) of the anchor cable 200, and is actually divided into three areas or parts: the central part 6 of the anchor cable, which runs from the central weight 1 to the inner pulleys of the sub-lines 200c, 200d, the middle part 7 of the anchor cable, including the part between the inner pulley 2 and the outer pulley (first rotational fixture 3), and the bottom 8 of the anchor cable, which runs from the outer pulley (first rotational fixture 3) to the anchor ring or bottom weight 4. As auxiliary elements, each anchor cable 200 may also include any of the following elements:

One or more intermediate pulleys (rotation guide means 11) are used to support the middle portion 7 of the anchored cable, sandwiched between the inner pulley 2 and the outer pulley (first rotation fixing means 3), and are used to support or assist in changing the path of the portion;

The intermediate buoy 9 is sandwiched in the bottom 8 of the anchoring line 200. If present, it is attached to the bottom weight 4 by the anchoring cable portion constituting the first part of the bottom 8.

The protruding structural arm 12 is used to support the anchor line 200, which is supported (or embedded) on the covering, or on the platform, or on the upper structure 20 of the floating platform 100, on which are suspended: the outer pulley (first rotating fixing device 3), the inner pulley 2 and the supporting pulley (rotating guide device 11) of the middle part 7 (if any).

The anchoring system of the present invention may also include other auxiliary elements that are common to conventional anchoring systems and can assist in the maneuvering of the floating platform 100 in its location operation installation/uninstallation, such as winches, windmills, cable bollards or other elements typical of any conventional anchoring system.

Each anchoring line 200 has a direct sub-line 200d and a cross sub-line 200c, and the inner pulley (second rotating fixture 2c) is located directly opposite to the outer pulley (first rotating fixture 3). The anchoring system has an even number of protruding structural arms 12 and corresponding anchoring lines 200, which are arranged two to two circumferentially in opposite positions.

In the design position, in a still and calm sea, the bottoms 8 of the anchor cables of all anchoring sub-lines 200c, 200d may be vertical (and parallel to each other).

Alternatively, the bottoms 8 of all anchored sub-lines 200c, 200d may diverge slightly, ie the anchoring points of the anchored cables on the bottom weight 4 are more horizontally separated from the central counterweight 1 than the outer pulleys (first rotational fixture 3).

The floating platform 100 may include the following elements:

- Platforms or main structures 400, partially submerged and of any geometric shape;

- Tower 13, supporting the offshore wind turbine, is located just above the floating platform 100;

- A complete offshore wind turbine with its cabin 14 mounted on a corresponding tower 13;

- a central counterweight 1, located on the central axis 300 of symmetry of the floating platform 100, suspended from the central part 6 of all anchor lines 200. Inside this there are several ballast compartments or flooded chambers, subject to the following restrictions: when all ballast compartments are empty, the central counterweight 1 has a slightly positive buoyancy (it floats). When one or more ballast compartments are flooded, the buoyancy of the central counterweight 1 becomes slightly negative (if it sinks). When all ballast compartments are flooded, the central counterweight 1 presents a (net) weight that is considerable (e.g. at least equal to 15% of the total weight of the floating platform 100);

- 4 or 6 projecting structural arms 12 for supporting anchoring wires 200, arranged radially around the symmetrical central axis 300 of the body of the floating platform 100. External pulleys (first rotational fixing means 3) for suspending the wires associated with each projecting structural arm 12 from the ends 121, 122 of each projecting structural arm 12. These pulleys can be single (with one pulley) or multiple (with several crossed pulleys);

- Anchor cables, suspended from two pulleys, an inner pulley 2 and an outer pulley (first rotating fixture 3) of each projecting structural arm 12. The central section 6 of the anchor cable is suspended from the inner pulley 2 and fastened to the central counterweight 1. The bottom section 8 of the anchor cable is suspended from the outer pulley (first rotating fixture 3) and fastened to an anchor ring, to a bottom weight 4 or to an anchor fastened to the seabed 5. The anchor cable can be single (one cable) or multiple (several cables).

The hull or main structure 400 of the floating platform has two main loading conditions: the transport condition, with all ballast tanks empty and floating freely with a characteristic waterline 21, and the operational condition, with all anchor lines 200 connected to the seabed 5 and bearing the net weight of the central counterweight 1. Some of the ballast tanks may be completely or partially filled so that the waterline 21 corresponds to the set waterline (operating draft 22).

According to a possible embodiment, the floating platform 100 includes the following elements:

- Four cylindrical floaters or floating elements 500, separated from the central axis 300 of the floating platform 100 and evenly distributed all around. In ballasted condition the waterline 21 is located at half the height of the floaters, defining them into two volumes, the submerged zone 15 and the surfaced or surfaced zone 16 (floating stop). In ballasted condition (transporting the floating platform 100) the floating surface provides the stability required for all transport operations. In operational condition the floaters are completely submerged and do not provide stability;

- Four legs or spokes 600, approximately prismatic in shape, inclined relative to the vertical, connecting each buoy or floating element 500 to the stationary floating platform 100. In the ballasted condition, they are completely surfaced, but in the operational condition, they have a submerged part or submerged radial zone 17 in the operational condition, and another non-submerged part or zone 18 above the waterline 21 or the operating draft 22. The floating platform 100 is not inherently stable in the operational (or designed) condition;

- four projecting structural arms 12, arranged radially and substantially horizontally, for supporting the pulleys of the anchoring system;

- reinforcing or resisting structural rings 19, at the base of the superstructure 20, fastening legs or beams 600, connected to the projecting structural arms 12 of the float and supporting anchor lines 200;

- a superstructure 20, above the reinforcing ring 19, serving as the base of the tower 13 of the wind turbine, in which the electronic equipment of the wind turbine or the electronic connection system of the wind turbines of the wind farm can be arranged;

- Tower 13 with wind turbines.

According to another possible embodiment, the floating platform 100 includes the following elements:

- a vertical axis cylindrical platform or main structure 400, with three different zones: a lower part or submerged zone 15, submerged under ballast, an upper part or never submerged zone 18, always above the floating or working draft 22, and an intermediate zone or surfaced or unsurfaced zone 16, between the ballast waterline and the design waterline;

- Four projecting structural arms 12 supporting pulleys of an anchoring system, fastened to the upper part of the platform or from the unflooded area 18, with anchoring lines 200 suspended from each projecting structural arm 12.

- A mooring ring, clustering four bottom weights 4, provides the necessary stability to the floating platform 100 (according to the embodiment herewith with a cylindrical hull) during transport and installation operations and is incompatible with the use of fixed anchors to the seabed 5, since they are not stable themselves.

According to another alternative embodiment, the floating platform 100 includes the following elements:

Four arms (and therefore four anchor lines and four legs). The main and characteristic elements of its geometry are:

- a submerged platform, formed by a slender floating ring 700 of large diameter (compared to its height or thickness), having two parts in the ballasted condition, a submerged zone 15, always submerged, and another surfacing or floating zone 16, which in the ballasted condition is located above the waterline 21, but is completely submerged in operation;

- four legs or spokes 600, inclined relative to the vertical and evenly distributed, connecting the submerged platform to the impedance structure ring 19;

- four projecting structural arms 12, grasping the anchoring lines 200 of the pulley and anchoring system; these four projecting structural arms 12 are fastened to the submerged platform and are also inclined with respect to the vertical direction;

- Central part 6, all anchoring sub-lines 200c, 200d are routed from the inner pulley 2 to the counterweight 1, passing through the inner hollow of the floating ring 700, forming a submerged platform or main structure 400.

These floating platforms 100 are inherently stable under pressure and can follow the following simplified sequence of installation phases:

- constructing the platform 100 by any conventional shipbuilding process and launching (throwing into the water). Simultaneously constructing the center weight 1, all ballast compartments are empty, and launching it into the water;

- All on-board equipment, including tower 13 and wind turbines, has been completed. The platform is now floating under ballasted conditions and is fully stable with all ballast compartments empty;

- fixing the bottom anchors of the floating platform 100 at its destination (by means of foundation piles, bottom weights, anchor rings or any other conventional anchoring system), installing the lower part of the bottom 8, hooked to the intermediate buoy 9, which has a buoyancy slightly higher than the cable's own weight and connected to the seabed; the buoy 9 maintains buoyancy at half height, all at the same depth;

- Move the floating platform 100 and the counterweight 1 to its destination by using a conventional tugboat. The central counterweight 1 is located below the axis of the floating platform 100;

- Connect all cables anchoring the sub-lines 200c, 200d to the central counterweight 1 and the intermediate buoy 9; loosen the cables at this point, as they are somewhat longer than the actual distance between the counterweight 1, the external pulley (first rotating fixture 3) and the intermediate buoy 9;

- Towing the floating platform 100 sideways (using a tugboat) until the cables of the anchoring system are slightly taut;

- Very slowly submerge the ballast tank 1; when the ballast 1 reaches an apparent density equal to that of seawater, it begins to sink, dragging the floating platform 100 to its designed position;

- The apparent density of the ballast 1 increases, the tension of the cable increases, and the floating platform 100 begins to sink slowly. When all the ballast compartments of the central ballast 1 are full, the floating platform 100 is almost at its design draft or operating draft 22;

- Correcting the draft of the floating platform 100 by filling in whole or in part any ballast compartment or flooding chamber of the floating platform 100 (the buoyancy element 500 or the buoyancy ring 700);

- The floating platform 100 is electrically connected to the resting wind farm.

At this point, the floating platform 100 is fully operational.

These floating platforms 100 are inherently stable under pressure and can follow the following simplified sequence of the de-installation phase (the opposite of the sequence of the installation phase described above):

- The floating platform 100 is electrically connected to the resting wind farm;

- emptying the ballast compartment or flooded chamber of the floating platform 100 (the floating element 500 or the floating ring 700);

- emptying the ballast compartment or flooding chamber of the centre weight 1 by hydraulic pumps or by injection of compressed air;

- When the counterweight 1 loses its net weight, the cable of the anchor line 200 becomes slack; the floating platform 100 slowly rises, and the counterweight 1 moves toward the sea surface;

- When the submerged buoy or floating element 500 of the floating platform 100 reaches the sea surface, the floating platform 100 regains stability and no longer requires the stability provided by the anchoring system cables;

- The tugboat is connected to the floating platform 100 and applies a lateral force, which makes it easy to move the floating platform 100 away from the equilibrium position;

- When the counterweight 1 reaches the sea surface, the floating platform 100 has moved sideways, emptying the ballast compartment of the counterweight 1 until the full buoyancy for the transport situation is obtained;

- Release the towing cable from the tugboat and then release all the central parts 6 of the hooked counterweight 1 and all the bottom parts 8 of the intermediate buoy 9.

At this point, both the floating platform 100 and the counterweight 1 are floating on their own, with all the stability they require, ready to be moved to another location or port for maintenance operations.

1: Counterweight 2: Internal pulley 2c: Second rotating fixture 2d: Third rotating fixture 3: First rotating fixture 4: Bottom weight, back weight 5: Seabed 6, 6c, 6d: Center 7, 7c, 7d: Middle part 8: Bottom, bottom leg 8c, 8d: Bottom 9: Middle buoy 10: Common point 11: Rotating guide device 12: Protruding structural arm 12a: First arm 12b: Second arm 13: Tower 14: Engine room 15: Submerged area 16: Emerging area 17: Submerged radial area 18: Never submerged area 19: Structural ring 20: Superstructure 21: Floating line, waterline 22: Working draft 100: floating platform 121: first end 122: second end 200: anchor line 200c: cross line 200d: direct line 300: center axis 400: main structure 500: floating element 600: radial 700: floating ring F1: windward force F2: leeward force FH: horizontal force Fx: force Mf: bending moment Q: weight α: angle β: angle

A portion of the explanation of at least one embodiment of the present invention is by way of illustration and not limitation, including the following figures.

FIG. 1 is a front view schematic diagram showing an embodiment of an anchoring system according to the present invention, showing two anchoring lines (arranged in the same plane) in a static position.

FIG. 2 is a schematic diagram showing the theoretical placement of two anchor lines in a balanced anchor system according to the present technical field.

FIG. 3 is a schematic diagram showing the force acting on a structure using the anchoring system of the present invention.

FIG. 4 shows a diagram similar to that of FIG. 1 , with the buoy having been pressed against the bottom of the anchor line.

FIG. 5 is a schematic diagram of the anchoring system of FIG. 4 , which shows the horizontal and vertical displacements of the anchoring system under the action of waves and wind.

FIG. 6 is a schematic diagram showing the displacement of the anchoring system, with the bases of directly opposite anchoring lines being parallel.

FIG. 7 is a schematic diagram showing the displacement of the anchoring system, where the bases of directly opposite anchoring lines diverge.

FIG8 is a bird's-eye view schematic diagram of the anchoring system according to the present invention, where it can be observed that two pairs of anchoring lines (ie, four anchoring lines) are arranged in two vertical planes.

FIG. 9 shows a top view of the anchoring system of FIG. 8 .

FIG10 shows a front view of the first stage of installation of the anchoring system according to the present invention, in which four protruding structural arms of the floating platform (two of which are in the vertical plane of the visual diagram) can be seen, supporting four anchoring lines of two pairs of anchoring lines, and the second part (upper part) of the bottom of the anchoring line is not connected to the buoy of the first part (lower part) of the bottom of the anchoring line.

FIG. 11 is a schematic diagram of the anchoring system of FIG. 10 , wherein a second portion of the bottom of the anchoring line has been connected to the buoy.

FIG. 12 is a schematic diagram of the anchoring system of FIG. 11 , wherein the submerged chamber and the counterweight of the floating element are submerged.

Figure 13 shows a side schematic diagram of a first embodiment of the anchoring system according to the present invention, wherein the floating platform includes a main structure in the shape of a cylindrical-conical axis, having four protruding structural arms, which are observed to support four anchoring lines, and wherein the main structure of the floating platform includes four foundation piles connected to this main structure, and each radial includes a floating element at its end.

FIG. 14 is a bird's-eye view of the anchoring system of FIG. 13 .

FIG. 15 is a front view schematic diagram of the anchoring system of FIGS. 13 and 14 .

FIG16 shows a side schematic diagram of a second embodiment of the anchoring system according to the present invention, in which it is observed that the floating platform includes a main structure in the shape of a cylindrical-conical axis, having four protruding structural arms supporting four anchoring lines, and wherein the main structure of the floating platform includes three floating elements.

FIG. 17 is a bird's-eye view of the anchoring system of FIG. 16 .

FIG. 18 is a front view schematic diagram of the anchoring system of FIGS. 15 and 16 .

FIG. 19 is a schematic side view of a third embodiment of the anchoring system according to the present invention, wherein the floating platform is observed to include a main structure in the shape of a floating ring having four protruding structural arms supporting four anchoring lines.

FIG. 20 is a bird's-eye view of the anchoring system of FIG. 19 .

FIG. 21 is a schematic side view of the anchoring system of FIGS. 19 and 20 .

1: Counterweight

4: Bottom weight

5: Seabed

9: Middle buoy

10: Commonalities

200: Anchor line

200c: Cross sub-line

200d: Direct sub-line

300: Center axis

Claims (15)

An anchoring system, comprising: A floating platform; and At least one pair of anchoring lines, configured to fix or anchor the floating platform to a seabed through at least one bottom of each anchoring line, wherein each anchoring line also includes a center portion attached to a counterweight, wherein each pair of anchoring lines includes two anchoring lines arranged in a plane passing through a central axis of the floating platform, and respectively located on one side and the other side of the central axis of the floating platform, wherein the anchoring system includes at least one first rotation fixing device for each anchoring line, wherein each first rotation fixing device is fixed to a first point of the floating platform, and is configured to fix each anchoring line to the floating platform at the first point of the floating platform, and allow the anchoring line to slide along the first rotation fixing device, and is characterized in that: Each of the anchoring lines includes at least one direct sub-line and one cross sub-line, each including its own anchoring cable or chain, wherein each of the direct sub-line runs from the first rotating fixture to the counterweight without passing through the central axis of the floating platform, and wherein each of the cross sub-line runs from the first rotating fixture to the counterweight and passes through the central axis of the floating platform, The anchoring system includes at least one second rotating fixture for each anchoring line, wherein each second rotating fixture is fixed to a second point of the floating platform and is configured to fasten each cross sub-line of each anchoring line to the floating platform at the second point of the floating platform and allow the cross sub-line to slide along the second rotating fixture, so that each cross sub-line is routed from the first rotating fixture to the counterweight and first passes through the central axis of the floating platform and then slides along the second rotating fixture. The anchoring system as described in claim 1 is characterized in that: the floating platform includes a pair of protruding structural arms for each pair of the anchoring lines, wherein each pair of the protruding structural arms includes a first arm and a second arm symmetrically arranged relative to the central axis of the floating platform, wherein each of the protruding structural arms is attached to a main structure of the floating platform, wherein each of the protruding structural arms radially extends from a first end attached to the main structure of the floating platform to a second end projected outside the floating platform, wherein the at least first rotational fixing device is fixed to the floating platform corresponding to the second end of the first arm, and wherein the at least second rotational fixing device is fixed to a point on the floating platform corresponding to the second arm. The anchoring system as described in claim 2 is characterized in that the main structure of the floating platform includes a shaft having a geometric shape of a cylindrical shaft, a conical shaft or a pyramidal shaft. The anchoring system as described in claim 3 is characterized in that it further includes a plurality of spokes connected to the main structure, and each free end of each of the spokes has a floating element. The anchoring system as described in claim 4 is characterized in that the floating element includes at least one submerged chamber. The anchoring system as described in claim 3 is characterized in that the main structure includes at least one floating element. The anchoring system as described in claim 6 is characterized in that the at least one floating element includes at least one submerged chamber. The anchoring system as described in claim 2 is characterized in that the main structure of the floating platform includes a ring-shaped geometry, and the ring is connected to a cylindrical shaft, a conical shaft or a pyramidal shaft through the spoke. The anchoring system as described in claim 8 is characterized in that the main structure constitutes a floating ring. An anchoring system as described in claim 9, characterized in that the floating ring includes at least one submerged chamber. The anchoring system as described in any one of claims 1 to 10 is characterized in that it further includes at least one third rotating fixture for each of the anchoring lines, wherein each of the third rotating fixtures is fixed to a third point of the floating platform and is configured to attach each of the direct sub-lines of each of the anchoring lines to the floating platform at the third point of the floating platform, allowing the direct sub-lines to slide along the third rotating fixture, so that each of the direct sub-lines passes through and slides along the third rotating fixture and is routed from the first rotating fixture to the counterweight. The anchoring system as described in any one of claims 1 to 11 is characterized in that it further includes at least one rotational guide device for each of the anchoring lines, wherein each of the rotational guide devices is attached to a fourth point of the floating platform and is configured to guide the track of the cross sub-line of each of the anchoring lines, allowing the cross sub-line to slide through the rotational guide device, so that each of the cross sub-line passes through and slides along the rotational guide device and is routed between the first rotational fixing device and the second rotational fixing device. An anchoring system as described in any one of claims 1 to 12, characterized in that each bottom of each anchoring line includes a buoy, which divides the bottom into a first part running between the seabed and the buoy, and a second part running between the buoy and the at least one first rotating fixing device. An anchoring system as described in any one of claims 1 to 13, characterized in that the counterweight includes at least one submersion chamber. A method for installing a floating platform using an anchoring system as described in claim 14, characterized in that the method comprises: At a location where the floating platform is installed, setting and/or anchoring at least one anchor and/or at least one bottom weight, and/or at least one anchoring ring and/or a set of foundation piles to the seabed; Moving the floating platform and the counterweight to its installation location, wherein the at least one submerged chamber is located in a non-submerged position; Attaching a free end of the bottom of each of the anchoring lines: To the at least one anchor and/or the at least one bottom weight, and/or the at least one anchoring ring and/or the set of foundation piles, or; to a buoy, previously connected by a first portion of the bottom of the anchor line to the at least one anchor and/or the at least one bottom weight, and/or to the at least one anchor ring and/or to the set of foundation piles; fixing a free end of the central portion of each of the anchor lines to the counterweight; pulling the floating platform sideways until the anchor lines are taut; and flooding the at least one buoyancy chamber.

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