Tensioning type shared mooring system suitable for deep sea and capable of changing fan anchor point position

Abstract

The invention discloses a tension type shared mooring system suitable for a deep sea and capable of changing fan anchor point positions, and belongs to the field of ocean renewable energy sources. Comprising a lower layer array composed of floating body units and an upper layer array composed of fan basic units. Each floating body unit comprises a floating body and a pile anchor connected through a floating body mooring rope; the number of the floating body mooring cables and the number of the pile anchors in each floating body unit are consistent; a pile anchor can be shared between every two adjacent floating body units; the floating body mooring rope is independently used for each floating body and cannot be shared; and the floating body units are arranged in a matrix form. Each fan basic unit comprises a fan and a fan mooring rope, and the fan mooring rope comprises a shared fan mooring rope and an independent fan mooring rope; the adjacent fans are connected through shared fan mooring cables, and the fans are connected with the floating bodies in the adjacent floating body units below the fans through independent fan mooring cables. According to the invention, the development requirements of the floating type wind power industry are well met.

Description

Technical Field

[0001] The present invention relates to the field of marine renewable energy, and in particular to a tensioned shared mooring system with variable wind turbine anchor point positions suitable for deep-sea floating wind farms. Background Art

[0002] As a clean and renewable energy utilization method, offshore wind power generation has received great attention from global energy development in recent years. It has significant advantages over onshore wind power generation. First of all, the wind speed of offshore wind farms is high and stable. Due to the flat and open terrain in the marine environment, there is no interference from terrain and obstacles, the deployment area is large, the wind energy resource density is greater, and the power generation efficiency is higher. Secondly, offshore wind farms are usually located in sea areas far away from the coast, which greatly reduces the impact on the nearshore environment. Therefore, a floating wind farm consisting of multiple floating wind turbines can be arranged in the deep sea. The traditional mooring system refers to a set of positioning systems independently designed for a floating platform, including anchor points or anchor piles, anchor cables or anchor chains, and connecting devices. Usually, an anchor point or an anchor pile is equipped with an anchor cable or anchor chain, and the two ends of the mooring cable are connected to the floating platform and the anchor pile respectively. The high construction cost of floating wind turbines and their mooring systems has always been an important reason restricting the development of deep-sea floating wind farms. For example, according to the large triangle shared mooring system for a floating wind farm disclosed in Chinese Patent Publication No. CN 118270174 A, the mooring system is an important component of deep-sea floating wind power equipment, and its cost accounts for 20%-30% of the total investment cost of floating wind power. In fact, due to the limitations of actual construction technology, or the cables and anchor piles have not yet been fully standardized, the actual construction cost of the mooring system is higher than this proportion. Secondly, the traditional mooring system also makes the maintenance of floating wind turbines, especially the maintenance of large components that need to be returned to the port, very difficult. For example, a method for maintaining large components of floating wind turbines based on towing to the port is disclosed in Chinese Patent Publication No. CN 118049351 A. In addition. In addition, once a traditional mooring system is deployed, its layout is difficult to change. At sea, especially in the deep sea, the sea conditions are complex and seasonal. This defect of difficulty in changing the layout often results in the mooring system having to be deployed according to the most dangerous sea conditions at the wind farm site, which in turn leads to excessive safety redundancy of the mooring system under general sea conditions, increasing the construction cost of the mooring system. Summary of the invention

[0003] (a) The technical problems solved by the present invention are:

[0004] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a tensioned shared mooring system with variable wind turbine anchor point positions suitable for deep sea. The tensioned shared mooring system with variable wind turbine anchor point positions suitable for deep sea is different from the traditional mooring system one pile one cable mode, which can reduce the traditional mooring cost, while taking into account the reduction of the maintenance cost of floating wind turbines, especially the maintenance cost of large components that need to return to the port, and can change the layout method according to the sea conditions of the wind farm, reducing unnecessary safety redundancy while ensuring safety.

[0005] (b) In order to achieve the above object, the technical solution of the present invention is:

[0006] A tensioned shared mooring system with variable wind turbine anchor point positions suitable for deep sea includes a lower array composed of floating units and an upper array composed of wind turbine basic units.

[0007] Each floating unit includes a floating body and pile anchors connected by floating system mooring cables; the number of floating system mooring cables and pile anchors in each floating unit is the same; pile anchors can be shared between two adjacent floating units; the floating system mooring cables are used separately for each floating body and cannot be shared; the floating units are arranged in a matrix form.

[0008] Each wind turbine basic unit includes a wind turbine and a wind turbine mooring cable. The wind turbine mooring cable includes a shared wind turbine mooring cable and an individual wind turbine mooring cable. Adjacent wind turbines are connected by a shared wind turbine mooring cable, and a wind turbine and a floating body in an adjacent floating body unit below the wind turbine are connected by an individual wind turbine mooring cable.

[0009] Furthermore, the number and positions of anchor points on the floating body, pile anchor and wind turbine are set according to requirements.

[0010] Furthermore, the floating unit adopts semi-tensioned mooring or tensioned mooring, and the floating body and pile anchors are arranged alternately.

[0011] Furthermore, the floating units should all be set at a certain depth below the water surface, which is 0.5-1 times the maximum wavelength of the local environmental waves, and the maximum depth does not exceed 50% of the average water depth of the wind farm.

[0012] Furthermore, the fans in each fan basic unit are arranged in a linear, triangular or regular hexagonal configuration.

[0013] Furthermore, depending on the different arrangement configurations of wind turbines in the wind turbine basic unit, adjacent individual wind turbine mooring cables may share an anchor point on a floating body, or may use an anchor point of a floating body separately.

[0014] Furthermore, the wind turbine mooring cable adopts tensioned mooring; according to the actual sea conditions, anchor points in different positions can be selected to realize the movement of the anchoring position of the wind turbine mooring cable, thereby changing the angle between the wind turbine mooring cables to form open moorings at different angles.

[0015] Furthermore, the floating mooring cable is made of steel, polyester fiber or composite material; the wind turbine mooring cable is made of carbon fiber material.

[0016] The principle of the present invention is:

[0017] The upper and lower layers of mooring design are adopted, with the upper layer being the wind turbine sequence and the lower layer being the floating body sequence. The floating body adopts semi-tensioned mooring or tensioned mooring, which does not rely on the weight of the floating system mooring cable, can adapt to various dynamic loads and maintain stability. The lower array composed of all floating bodies is located at a depth of 0.5 to 1 times the maximum wavelength and no more than 50% of the water depth. It is less affected by waves, which improves the overall stability of the lower array, thereby ensuring the relative stability of the spatial position of the floating anchor point sequence formed by the anchor points on the floating bodies. The upper array composed of wind turbine basic units uses wind turbine mooring cables made of carbon fiber materials and a tensioned mooring method to ensure the relative stability and dynamic adaptability of the spatial position of each wind turbine in the upper array. The anchor point of the wind turbine mooring cable is set on the floating body instead of directly on the seabed, which greatly reduces the length of the wind turbine mooring cable of the wind turbine itself. In the case where the floating body is set at a shallow water depth, the connection between the wind turbine mooring cable and the floating body anchor point can be directly disconnected, the wind turbine mooring cable can be recovered, and then the wind turbine can be directly moved without setting up an additional replacement floating body to fix the position of the wind turbine mooring cable; in the case where the floating body is set at a deeper water depth, when setting up an alternative floating body for positioning the wind turbine mooring system, the requirements for the floating body are also reduced because the wind turbine mooring cable is lighter, which simplifies the traditional wind turbine maintenance steps, especially the maintenance steps of the large components that need to be disassembled and assembled for returning to the port. Secondly, the simplified wind turbine movement method mentioned above allows the wind turbine to quickly change its layout. For the sea conditions in different periods, it is no longer necessary to adopt a unified fixed form, but to adopt the most favorable layout form for the sea conditions, give full play to the advantages of each layout form, and reduce the required wind turbine mooring cable strength that is forced to increase due to the variability of the sea conditions by changing the layout form, thereby fully optimizing the setting of safety redundancy and reducing costs. Finally, the mooring system of the upper array adopts a unit modular design, which is composed of multiple wind turbine basic units. Multiple wind turbine mooring cables can be shared within each wind turbine basic unit or between wind turbine basic units, which fully reduces the construction and maintenance costs of the mooring cables.

[0018] (c) The beneficial effects of the present invention are:

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention proposes a tensioned shared mooring system with layered variable anchor points for a floating wind farm, which can significantly reduce the construction cost of a mooring system for a large-scale floating wind farm in the deep sea, and at the same time simplifies the implementation steps of disassembling and assembling the mooring cable of a traditional floating wind turbine for maintenance, which has the significant advantages of being easy to maintain, especially easy to maintain large components after returning to the port, and reduces the maintenance cost of floating wind turbines. The shared mooring system proposed by the present invention includes a number of floating wind turbines, individual wind turbine mooring cables, shared wind turbine mooring cables, a floating body below the water surface that provides an anchor point, and an anchor pile fixed to the seabed. One anchor pile can be connected to two or more floating mooring cables, and one floating anchor point can be connected to two or more wind turbine mooring cables, effectively reducing the manufacturing and construction costs. The present invention proposes a tensioned shared mooring system with layered variable anchor points for a floating wind farm, in which the wind turbine mooring cable is anchored on the anchor point of the floating body. Compared with the traditional mooring system directly anchored on the seabed, since the floating body is arranged at 0.5 to 1 times the maximum wavelength depth of the local waves of the wind farm, it is more convenient to disassemble and assemble, and different mooring system layouts can be replaced according to the actual sea conditions, which has a significant advantage in the flexibility of the mooring system. In addition, the tensioned shared mooring system with layered variable anchor points for a floating wind farm proposed by the present invention, the layered anchoring characteristics, provide a certain degree of amplitude range for both the wind turbine mooring cable and the floating system mooring cable, thereby avoiding fatigue damage caused by continuous tensioning of the mooring cable. Finally, the tensioned shared mooring system with layered variable anchor points for a floating wind farm proposed by the present invention meets the development needs of the floating wind power industry well, and still has sufficient safety redundancy and risk resistance under the premise of reducing the development cost of floating wind farms. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of layered mooring of the present invention;

[0021] Figure 2 It is a schematic diagram of the lower array of the floating unit of the present invention;

[0022] Figure 3 It is a three-dimensional schematic diagram of the mooring system of the lower array of floating bodies of the present invention;

[0023] Figure 4 A schematic diagram of a linear basic unit of an upper fan according to an embodiment of the present invention;

[0024] Figure 5 A schematic diagram of a triangular basic unit of an upper fan according to an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of a regular hexagonal basic unit of an upper-level fan according to an embodiment of the present invention;

[0026] Figure 7 It is a schematic diagram of a semi-tensioned mooring cable of a floating unit according to an embodiment of the present invention;

[0027] Figure 8 It is a schematic diagram of a tensioned mooring cable of a floating unit according to an embodiment of the present invention;

[0028] Fig. 9 A schematic diagram of a wind turbine tensioned mooring cable according to an embodiment of the present invention;

[0029] Fig.10 Schematic diagram of the overall mooring system using the upper wind turbine regular hexagonal basic unit combination according to the embodiment of the present invention. (a) is the overall schematic diagram using the regular hexagonal basic unit combination; (b) is the three-dimensional mooring schematic diagram of a single regular hexagonal basic unit; (c) is the three-dimensional mooring schematic diagram of the floating unit used by the single regular hexagonal basic unit.

[0030] Among them: SC shared wind turbine mooring cable; AC individual mooring cable; PA pile anchor; WT floating wind turbine; FB floating body. DETAILED DESCRIPTION

[0031] The above contents of the present invention will be further described in detail below in conjunction with specific implementations, but the scope of the present invention is by no means limited to the following examples:

[0032] Specific implementation method:

[0033] In order to make the above features and advantages of the present invention more clearly understood, embodiments are given below with reference to the accompanying drawings for detailed description as follows.

[0034] One point that needs to be explained in the present invention is that when the wind turbine basic unit is connected or fixed to the floating unit through the wind turbine mooring cable, the specific connection method can be a fixed connection, or a coupling or a connection.

[0035] The invention discloses a tensioned shared mooring system with variable wind turbine anchor point positions suitable for deep sea, comprising a lower array composed of floating body units and an upper array composed of wind turbine basic units.

[0036] Each floating unit includes a floating body and a pile anchor connected by a floating system mooring cable; the number of floating system mooring cables and pile anchors in each floating unit is the same; the pile anchors can be shared between two adjacent floating units; the floating system mooring cable is used separately for each floating body and cannot be shared; the floating units are arranged in a matrix. Specifically: the internal floating system mooring cables in the lower array can share a pile anchor, and the external floating system mooring cables can use a pile anchor separately;

[0037] Each wind turbine basic unit includes a wind turbine and a wind turbine mooring cable. The wind turbine mooring cable includes a shared wind turbine mooring cable and an individual wind turbine mooring cable. Adjacent wind turbines are connected by a shared wind turbine mooring cable, and a wind turbine and a floating body in an adjacent floating body unit below the wind turbine are connected by an individual wind turbine mooring cable.

[0038] The number and position of anchor points on the floating body, pile anchor and wind turbine are set according to needs.

[0039] Depending on the different wind turbine arrangement configurations in the wind turbine basic unit, adjacent individual wind turbine mooring cables can share a floating anchor point or use a floating anchor point separately. Wind turbine mooring cables are tensioned moored; depending on the actual sea conditions, anchor points in different positions can be selected to move the anchoring position of wind turbine mooring cables, thereby changing the angle between wind turbine mooring cables to form open moorings at different angles.

[0040] The lower floating unit should be set at a certain depth below the water surface, which is 0.5-1 times the maximum wavelength of the local environmental waves, and the maximum depth shall not exceed 50% of the average water depth of the wind farm.

[0041] See also Figure 4 The wind turbine arrangement configuration is linear, and each wind turbine basic unit is composed of a number of wind turbines arranged linearly. Inside each wind turbine basic unit, every two wind turbines are connected by a shared wind turbine mooring cable SC. Under each wind turbine, there is a vertical separate wind turbine mooring cable connected to the anchor point on the floating body. The wind turbines at both ends are additionally provided with two separate wind turbine mooring cables connected and fixed to the anchor points on the floating body.

[0042] See also Figure 5 The wind turbine arrangement configuration is a triangle, each wind turbine basic unit is composed of three wind turbines, each wind turbine basic unit has a floating anchor point, each of the three wind turbines has a separate wind turbine mooring cable connected to the floating anchor point, and the three wind turbines are connected through three shared wind turbine mooring cables SC, and each wind turbine has an additional separate wind turbine mooring cable in the direction along the line connecting the central floating anchor point and itself, and is connected to a floating anchor point or wind turbine of another wind turbine basic unit through the separate wind turbine mooring cable. Multiple triangular wind turbine basic units can be combined with each other to form an upper array.

[0043] See also Figure 6The wind turbine arrangement configuration is a regular hexagon, each wind turbine basic unit is composed of six wind turbines, each wind turbine basic unit has a floating body inside, a floating body anchor point is provided on the floating body, and each of the six wind turbines has a separate wind turbine mooring cable connected to the floating body anchor point. The six wind turbines are connected to each other through six shared wind turbine mooring cables, and each wind turbine has two floating bodies along the direction of the line connecting the two adjacent wind turbines, each of which has a floating body anchor point, and each wind turbine is connected to the two floating body anchor points through two separate wind turbine mooring cables. Each wind turbine has a floating body along the direction of the line connecting the floating body inside the wind turbine basic unit and the wind turbine, and a floating body anchor point is provided on it, and each wind turbine is connected to the floating body anchor point through a separate wind turbine mooring cable. Multiple regular hexagonal wind turbine basic units can be combined with each other to form an upper array.

[0044] The wind turbine mooring cables of the upper array are all made of carbon fiber and are tensioned to enhance their dynamic adaptability and overall space utilization. The floating units are semi-tensioned or tensioned, with the floating bodies and pile anchors arranged alternately. The floating mooring cables are made of steel. Figure 7-9 , Figure 7 It is a schematic diagram of a semi-tensioned mooring cable of a floating unit according to an embodiment of the present invention; Figure 8 It is a schematic diagram of a tensioned mooring cable of a floating unit according to an embodiment of the present invention; Fig. 9 Schematic diagram of a single tensioned mooring cable for a wind turbine according to an embodiment of the present invention.

[0045] When maintenance work is required, especially when the wind turbine needs to be towed to the port for maintenance of large parts, it can be determined whether a replacement float is needed to locate the mooring cable after it is released, depending on the actual water depth and the depth of the float. If it is in shallow water, the cable and mooring system can be directly disconnected from the anchor point of the float, and it can be directly recovered by the operation and maintenance ship or the wind turbine's own anchor cable recovery device, without the need to set up a replacement float; if it is in deeper water, it is necessary to set up a replacement float to locate the mooring cable of the wind turbine after it is released. Due to the existence of the lower array composed of floats, the length of the upper wind turbine mooring cable is reduced, and the use of carbon fiber materials, the weight of the wind turbine mooring cable is greatly reduced compared to the traditional mooring system directly anchored to the seabed, and the requirements for replacement floats are also greatly reduced. In addition, the weight of the mooring system itself has greatly reduced the impact on the release construction process, and the difficulty of construction is also reduced accordingly.

[0046] The upper wind turbine mooring cable and the lower floating system mooring cable, divided and transitioned by the lower array composed of floating bodies, together constitute a mooring system. In the depth direction, a new mooring method is formed, which is different from the traditional tensioned mooring that is approximately straight, and the overall shape is a broken line, providing a certain degree of amplitude range for both the wind turbine mooring cable and the floating system mooring cable, protecting the cable from fatigue damage.

[0047] When the floating body is set in shallow water, the mooring cable of the wind turbine can be directly released and recovered, and the upper array composed of wind turbines can realize rapid changes in layout.

Claims

1. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea, characterized in that: It includes a lower array composed of floating units and an upper array composed of wind turbine basic units; Each floating unit includes a floating body and a pile anchor connected by a floating system mooring cable; the number of floating system mooring cables and pile anchors in each floating unit is the same; the pile anchors can be shared between two adjacent floating units; the floating system mooring cable is used separately for each floating body and cannot be shared; the floating units are arranged in a matrix form; Each wind turbine basic unit includes a wind turbine and a wind turbine mooring cable. The wind turbine mooring cable includes a shared wind turbine mooring cable and an individual wind turbine mooring cable. Adjacent wind turbines are connected by a shared wind turbine mooring cable, and a wind turbine and a floating body in an adjacent floating body unit below the wind turbine are connected by an individual wind turbine mooring cable.

2. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: The number and position of anchor points on the floating body, pile anchor and wind turbine are set according to needs.

3. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: The floating body unit adopts semi-tensioned mooring or tensioned mooring, and the floating body and pile anchors are arranged alternately.

4. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: The floating units should be set at a certain depth below the water surface, which is 0.5-1 times the maximum wavelength of the local environmental waves, and the maximum depth shall not exceed 50% of the average water depth of the wind farm.

5. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: The fan arrangement configuration in each fan basic unit is linear, triangular or regular hexagonal.

6. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: Depending on the different arrangement configurations of wind turbines in the wind turbine basic unit, adjacent individual wind turbine mooring cables may share an anchor point on a floating body, or may use an anchor point of a floating body separately.

7. A tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: The wind turbine mooring cable adopts tensioned mooring; according to the actual sea conditions, anchor points in different positions can be selected to realize the movement of the anchoring position of the wind turbine mooring cable, thereby changing the angle between the wind turbine mooring cables to form open mooring at different angles.

8. The tensioned shared mooring system with variable wind turbine anchor point position suitable for deep sea according to claim 1, characterized in that: Floating mooring cables are made of steel, polyester fiber or composite materials; wind turbine mooring cables are made of carbon fiber materials.

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