Offshore foundation platform and tension leg load adjusting method

Abstract

The invention discloses an offshore foundation platform and a tension leg load adjusting method.The offshore foundation platform comprises a supporting body, a buoy, a driver and a tension leg, the buoy is connected to the supporting body and provided with a hollow inner cavity, at least part of the buoy is located below the seawater liquid level, and the buoy can move in the vertical direction relative to the supporting body; the driver is arranged between the supporting body and the buoy to drive the buoy to move relative to the supporting body, one end of each tension leg is connected with the supporting body, and the other end of each tension leg is connected with the seabed. According to the offshore foundation platform, the height of the offshore foundation platform is adjusted through the buoys, then the buoyancy acting on the supporting bodies is adjusted, the tension on the tension legs can be adjusted, the tension on the tension legs is always in a stable and controllable range, and therefore the stability of the platform can be improved, and the fatigue load of tendon materials of the tension legs can be relieved.

Description

Technical Field

[0001] The invention belongs to the technical field of offshore equipment, and in particular relates to an offshore foundation platform and a tension leg load adjustment method. Background Art

[0002] Offshore wind power has significant advantages such as no pollution, renewable, low cost and wide distribution. At present, offshore wind farms mainly use traditional fixed foundation wind turbines. However, the wind energy resources in the deep sea are more abundant than those in the near sea, with reserves of about 1 billion kilowatts, equivalent to twice the offshore resources, showing huge development potential. With the gradual advancement of offshore wind power development, the development area is bound to expand from the near sea to the deep sea. However, the cost of fixed foundations increases significantly when the water depth exceeds 50 meters, so floating foundations have become an economical and efficient choice for wind energy development in deep water areas.

[0003] In the relevant technology, floating foundations can be divided into various types according to the principle of stability, such as column type, semi-submersible type, tension leg type and barge type. Among them, the tension leg platform has excellent motion control performance, and the tendon system is used to ensure the stability of the platform. The tendon system, as a unique structure of the tension leg platform, can effectively limit the movement of the platform and ensure safety.

[0004] However, in deep sea areas, complex environmental excitations such as wind, waves, and currents will impose alternating loads on the platform. Although the strength of the tendon system meets the requirements of the specification, the alternating loads under long-term action may cause fatigue damage to the tendons, thereby affecting the overall stability of the platform and the power generation efficiency of the wind turbine. Therefore, solving the fatigue problem of the tendons is crucial to the safety and wind power efficiency of the tension leg platform. Summary of the invention

[0005] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0006] To this end, an embodiment of the present invention provides an offshore foundation platform, which can improve the stability of the platform and reduce the fatigue load of the tension hamstring tendon material.

[0007] An embodiment of the present invention provides a tension leg load adjustment method.

[0008] The offshore foundation platform of the embodiment of the present invention includes:

[0009] Support body;

[0010] A buoy, the buoy is connected to the support body, the buoy has a hollow inner cavity, and at least a portion of the buoy is located below the seawater level, and the buoy is movable in a vertical direction relative to the support body;

[0011] A driver, the driver being arranged between the support body and the buoy to drive the buoy to move relative to the support body;

[0012] A tension leg, wherein the number of the tension legs is multiple, one end of the tension leg is connected to the support body, and the other end of the tension leg is connected to the seabed.

[0013] The offshore foundation platform of the embodiment of the present invention adjusts its own height through the float, and then adjusts the buoyancy acting on the support body, so that the tension on the tension leg can be adjusted so that the tension on the tension leg is always within a stable and controllable range, thereby improving the stability of the platform and reducing the fatigue load of the tension leg tendon material.

[0014] In some embodiments, a tower is further included, wherein the tower is supported on the support body, the tower is arranged above the middle part of the support body, and the pontoon is arranged below the middle part of the support body.

[0015] In some embodiments, the lower portion of the tower has a sliding cavity opening downward, a partial section of the buoy is located in the sliding cavity and is movable along the sliding cavity, one end of the driver is connected to the tower, and the other end of the driver is connected to the buoy.

[0016] In some embodiments, the buoy includes a body section and a guide section, the guide section is arranged in the sliding cavity, the body section is located below the guide section, and the cross-sectional area of ​​the body section is larger than the cross-sectional area of ​​the guide section, and the body section and the guide section are both hollow structures;

[0017] And / or, the lower portion of the buoy is tapered.

[0018] In some embodiments, the driver is an electric push rod.

[0019] In some embodiments, it also includes a water level detection component and a controller. The water level detection device is arranged on the support body. The water level detection device is used to detect the height of the seawater level. The controller is connected to the water level detection device and the driver to control the action of the driver according to the height of the seawater level.

[0020] In some embodiments, a tension detection component is further included, wherein the tension detection component is connected to the tension leg to detect the tension on the tension leg.

[0021] In some embodiments, it also includes offshore equipment, which is arranged on the support body and is a wind power device or a photovoltaic device.

[0022] The tension leg load adjustment method in the embodiment of the present invention is used for adjusting the tension leg load of the offshore foundation platform in any of the above embodiments, and the adjustment method includes:

[0023] Obtain the height information of the seawater level in the area where the offshore foundation platform is located in real time;

[0024] Periodically calculating the average height of the seawater surface within the time range T;

[0025] Based on the average height, calculating the displacement of the buoy;

[0026] The actuator is controlled to drive the buoy to move relative to the support body.

[0027] In some embodiments, the time range T is 5 minutes to 20 minutes;

[0028] And / or, further comprising the steps of:

[0029] Obtaining the tension on the tension leg, and determining whether the tension is greater than a first threshold;

[0030] If yes, adjusting the float to move upward relative to the support body until the tension is less than a second threshold, wherein the second threshold is less than the first threshold;

[0031] If not, and the tension is less than the third threshold, the float is adjusted to move downward relative to the support body until the tension is greater than a fourth threshold, wherein the third threshold is less than the fourth threshold, and the fourth threshold is less than the second threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic structural diagram of the offshore foundation platform according to an embodiment of the present invention at a high water level.

[0033] Figure 2 It is a schematic structural diagram of the offshore foundation platform according to an embodiment of the present invention at a low water level.

[0034] Figure 3 It is a schematic structural diagram of an offshore foundation platform according to another embodiment of the present invention at a high water level.

[0035] Figure 4 It is a schematic structural diagram of an offshore foundation platform according to another embodiment of the present invention at a low water level.

[0036] Figure 5 Schematic diagram of the position of the buoy at high water level in an embodiment of the present invention.

[0037] Figure 6 Schematic diagram of the position of the buoy at low water level in an embodiment of the present invention.

[0038] Figure 7 4 is a flow chart of a tension leg load adjustment method according to an embodiment of the present invention.

[0039] Reference numerals:

[0040] 1. Support body;

[0041] 2. buoy; 21. body section; 22. guide section;

[0042] 3. Driver;

[0043] 4. Tension legs;

[0044] 5. Tower; 51. Sliding cavity;

[0045] 6. Wind power equipment;

[0046] 7. Sea water level;

[0047] 8. Water level detection component. DETAILED DESCRIPTION

[0048] Embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0049] like Figure 1-Figure 6 As shown, the offshore foundation platform according to the embodiment of the present invention includes a support body 1 , a buoy 2 , a driver 3 and a tension leg 4 .

[0050] The support body 1 is the main frame of the platform, which is used to build offshore wind power equipment 6, photovoltaic equipment and other offshore equipment above it. The buoy 2 is connected to the support body 1. The buoy 2 has a hollow inner cavity, and at least part of the buoy 2 is located below the seawater level 7. The buoyancy of the seawater acting on the buoy 2 can also act on the support body 1. The buoy 2 is movable in the vertical direction relative to the support body 1. By adjusting the position of the buoy 2 relative to the support body 1, the buoy 2 can be moved up and down in the vertical direction. When the height of the seawater level 7 remains unchanged, when the buoy 2 moves downward, the volume of the buoy 2 immersed below the seawater level 7 increases, and the buoyancy it receives also increases accordingly. When the buoy 2 moves upward, the volume of the buoy 2 immersed below the seawater level 7 decreases, and the buoyancy it receives also decreases accordingly. Therefore, when the height of the seawater level 7 changes, by actively adjusting the height of the buoy 2, the buoyancy acting on the buoy 2 can be adjusted, thereby maintaining the tension on the tension leg 4 within a reasonable range.

[0051] The driver 3 of the embodiment of the present invention is disposed between the support body 1 and the buoy 2, and is used to drive the buoy 2 to move relative to the support body 1. The driver 3 is an electric push rod, for example, the driver 3 is an electric push rod.

[0052] There are multiple tension legs 4, one end of which is connected to the support body 1, and the other end of which is connected to the seabed. Multiple tension legs 4 are used to pull the support body 1, so that the sum of the gravity of the support body 1 and the tension exerted on the support body 1 by the tension legs 4 is equal to the buoyancy of the support body 1 and the buoy 2.

[0053] The offshore foundation platform of the embodiment of the present invention can adjust the buoyancy acting on the support body 1 by adjusting its own height through the float 2, so as to adjust the tension on the tension leg 4 so that the tension on the tension leg 4 is always within a stable and controllable range, thereby improving the stability of the platform and reducing the fatigue load of the tendon material of the tension leg 4.

[0054] It is understandable that there may be a plurality of buoys 2 , and all of the buoys 2 may be movable in the vertical direction relative to the support body 1 , or only some of the buoys 2 may be movable in the vertical direction relative to the support body 1 .

[0055] For example, a portion of the buoys 2 are arranged along the circumference of the support body 1 and are fixedly connected to the support body 1, while one of the buoys 2 is located in the middle of the support body 1 and serves as the central buoy 2. The central buoy 2 can move in the vertical direction relative to the support body 1. When the central buoy 2 is adjusted, the support body 1 can be prevented from swaying and its stability can be maintained.

[0056] In some embodiments, the offshore foundation platform further includes a tower 5, which is supported on the support body 1, and the tower 5 is arranged above the middle part of the support body 1, and the buoy 2 is arranged below the middle part of the support body 1. The top of the tower 5 has a mounting portion for mounting wind power equipment 6 or photovoltaic equipment, so that offshore equipment such as wind power equipment 6 or photovoltaic equipment is kept away from the seawater surface 7 to ensure the safe operation of the equipment.

[0057] The tower 5 is usually arranged above the middle of the supporting body 1 .

[0058] Furthermore, the lower part of the tower 5 has a sliding cavity 51 with an opening facing downward, a part of the section of the pontoon 2 is located in the sliding cavity 51 and is movable along the sliding cavity 51, one end of the driver 3 is connected to the tower 5, and the other end of the driver 3 is connected to the pontoon 2. In other words, a part of the section of the pontoon 2 that can move in the vertical direction is arranged in the sliding cavity 51, so that the section and the sliding cavity 51 form relative sliding, and positioning and assembly are achieved, which improves the compactness of the structure and avoids affecting the overall stability of the equipment after adding the movable pontoon 2.

[0059] Optionally, the buoy 2 includes a main body section 21 and a guide section 22, the guide section 22 is arranged in the sliding cavity 51, the main body section 21 is located below the guide section 22, and the cross-sectional area of ​​the main body section 21 is larger than the cross-sectional area of ​​the guide section 22, and both the main body section 21 and the guide section 22 are hollow structures.

[0060] The cross-sectional dimension of the guide section 22 is smaller than that of the main section 21 , so that the guide section 22 can match the sliding cavity 51 of the tower 5 , while the volume of the main section 21 can meet the adjustment requirements.

[0061] Furthermore, the lower portion of the buoy 2 is tapered, for example, the body section 21 is configured to be tapered, so as to prevent the buoy 2 from encountering excessive resistance when moving.

[0062] In some embodiments, the offshore base platform also includes a water level detection component 8 and a controller. The water level detection device is arranged on the support body 1. The water level detection device is used to detect the height of the seawater level 7. The controller is connected to the water level detection device and the driver 3 to control the action of the driver 3 according to the height of the seawater level 7.

[0063] The controller can be connected to the control system of the offshore wind power equipment 6 or the photovoltaic equipment to achieve centralized control. After obtaining the height of the seawater level 7, the water level detection device can obtain the height that the buoy 2 needs to move relative to the support body 1, and then calculate the displacement of the buoy 2 according to the current height of the buoy 2, and the driver 3 drives the buoy 2 to move.

[0064] Furthermore, the offshore foundation platform further includes an offshore foundation platform tension detection assembly, which is connected to the tension leg 4 to detect the tension on the tension leg 4. The tension detection assembly is used to measure the tension on the tension leg 4 in real time, so as to provide data reference for the action of the driver 3. The tension of the tension leg 4 and the height of the seawater level 7 can complement each other and serve as data support for adjusting the displacement of the buoy 2, thereby improving the accuracy of the adjustment.

[0065] For example, the position of the buoy 2 is first adjusted according to the height of the seawater level 7, and then the position of the buoy 2 is fine-tuned according to the tension on the tension leg 4 to cope with the influence of the tension on the tension leg 4 in windy and rainy weather.

[0066] like Figure 7 As shown, the tension leg load adjustment method in the embodiment of the present invention is used for adjusting the tension leg load of the offshore foundation platform in any of the above embodiments, and the adjustment method includes:

[0067] S101. Acquire in real time the height information of the seawater level in the area where the offshore foundation platform is located.

[0068] S102, periodically calculating the average height of the seawater level within a time range T, the time range T being 5 minutes to 20 minutes, for example, the time range T being 5 minutes, 7 minutes, 8.5 minutes, 10 minutes, 15 minutes or 20 minutes, by adjusting the length of time T, the adjustment frequency of the buoy can be controlled, and it is ensured that the height change of the seawater level within a corresponding time period does not cause excessive fluctuation of the tension on the tension leg.

[0069] S103, calculating the displacement of the buoy based on the average height;

[0070] S104, controlling the driver to drive the buoy to move relative to the support body.

[0071] Of course, in order to further improve the accuracy of the adjustment, the displacement of the buoy can be further adjusted by the tension on the tension leg, which specifically includes the following steps:

[0072] S105: Obtain the tension on the tension leg, and determine whether the tension is greater than a first threshold.

[0073] S106: If yes, adjust the float to move upward relative to the support body until the tension is less than a second threshold, wherein the second threshold is less than the first threshold.

[0074] S107, if not, and the tension is less than the third threshold, adjust the float to move downward relative to the support body until the tension is greater than a fourth threshold, wherein the third threshold is less than the fourth threshold, and the fourth threshold is less than the second threshold.

[0075] It should be understood that the third threshold, the fourth threshold, the second threshold and the first threshold increase in sequence. Under normal circumstances, it is necessary to ensure that the tension of the tension leg is between the third threshold and the first threshold. When performing periodic adjustment, the tension of the tension leg needs to be adjusted to between the fourth threshold and the second threshold to ensure that it is within a reasonable range.

[0076] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0077] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0078] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0079] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0080] In the present invention, the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the described specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0081] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An offshore foundation platform, characterized in that: include: Support body; A buoy, the buoy is connected to the support body, the buoy has a hollow inner cavity, and at least a portion of the buoy is located below the seawater level, and the buoy is movable in a vertical direction relative to the support body; A driver, the driver being arranged between the support body and the buoy to drive the buoy to move relative to the support body; A tension leg, wherein the number of the tension legs is multiple, one end of the tension leg is connected to the support body, and the other end of the tension leg is connected to the seabed.

2. The offshore foundation platform according to claim 1, characterized in that: It also includes a tower, which is supported on the support body. The tower is arranged above the middle part of the support body, and the buoy is arranged below the middle part of the support body.

3. The offshore foundation platform according to claim 2, characterized in that: The lower part of the tower is provided with a sliding cavity opening downward, a partial section of the buoy is located in the sliding cavity and is movable along the sliding cavity, one end of the driver is connected to the tower, and the other end of the driver is connected to the buoy.

4. The offshore foundation platform according to claim 3, characterized in that: The buoy comprises a body section and a guide section, the guide section is arranged in the sliding cavity, the body section is located below the guide section, and the cross-sectional area of ​​the body section is larger than the cross-sectional area of ​​the guide section, and the body section and the guide section are both hollow structures; And / or, the lower portion of the buoy is tapered.

5. The offshore foundation platform according to claim 3, characterized in that: The driver is an electric push rod.

6. The offshore foundation platform according to any one of claims 1 to 5, characterized in that: It also includes a water level detection component and a controller. The water level detection device is arranged on the support body. The water level detection device is used to detect the height of the seawater level. The controller is connected to the water level detection device and the driver to control the action of the driver according to the height of the seawater level.

7. The offshore foundation platform according to claim 6, characterized in that: It also includes a tension detection component, which is connected to the tension leg to detect the tension on the tension leg.

8. The offshore foundation platform according to claim 1, characterized in that: It also includes offshore equipment, which is arranged on the support body and is a wind power device or a photovoltaic device.

9. A tension leg load adjustment method, characterized in that: The tension leg load adjustment method for the offshore foundation platform according to any one of claims 1 to 8 comprises: Obtain the height information of the seawater level in the area where the offshore foundation platform is located in real time; Periodically calculating the average height of the seawater surface within the time range T; Based on the average height, calculating the displacement of the buoy; The actuator is controlled to drive the buoy to move relative to the support body.

10. The tension leg load adjustment method according to claim 9, characterized in that: The time range T is 5 minutes to 20 minutes; And / or, further comprising the steps of: Obtaining the tension on the tension leg, and determining whether the tension is greater than a first threshold; If yes, adjusting the float to move upward relative to the support body until the tension is less than a second threshold, wherein the second threshold is less than the first threshold; If not, and the tension is less than the third threshold, the float is adjusted to move downward relative to the support body until the tension is greater than a fourth threshold, wherein the third threshold is less than the fourth threshold, and the fourth threshold is less than the second threshold.

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