A floating offshore wind power foundation with a suspension load adapted to water depth and a method of use

Abstract

The application relates to a water-depth-adaptive suspension ballast type floating offshore wind power foundation and a use method thereof, and belongs to the technical field of floating offshore wind power generation. The wind power foundation comprises a three-column semi-submersible foundation, a mooring system and a control system. The three-column semi-submersible foundation comprises three vertical columns, a support rod and a ballast caisson. The ballast caisson is connected with a sliding rail arranged on the side wall of the vertical column through a sliding rope, the ballast caisson is moved up and down relative to the vertical column, the position of the ballast caisson is adjusted through the control system, the position of the gravity center of the foundation and the draft are adjusted, different environmental conditions are adapted, and the stability and the overturning resistance are ensured. The use method comprises monitoring environmental conditions, calculating an overturning torque, calculating an overturning resistance torque, adjusting the depth of the ballast caisson and data recording and analysis. The depth required by the ballast caisson to be moved is deduced through the calculation of the overturning torque, so that the gravity center and the floating center of the foundation are kept at a proper position, and the risk of overturning of the foundation is reduced.

Description

Technical Field

[0001] This invention relates to the field of floating offshore wind power technology, and more specifically, to a floating offshore wind power foundation adapted to water depth and suspended ballast, and its usage method. Background Technology

[0002] In recent years, with the advancement of science and technology at home and abroad, wind power generation has shown a trend of development towards the deep sea. In deep sea areas, floating offshore wind power foundations have received widespread attention, with three common types: Spar column type, TLP tension leg type, and semi-submersible type.

[0003] Spar column foundations are simple in design and manufacturing process with few moving parts, but construction and installation are difficult. In order to meet stability requirements, the overall weight of Spar column foundations is large and the draft is large, which limits the feasibility of returning them to the dock for maintenance.

[0004] TLP (Tension Leg) foundations use less steel and have fewer moving parts, allowing for onshore installation and commissioning, thus avoiding various challenges associated with offshore installation. However, TLP foundations balance the upward excess buoyancy of the float through vertical mooring tension, resulting in extremely high stress and risk on the mooring and anchoring systems. The natural frequency of the TLP foundation is prone to resonance with the frequency of ocean waves, leading to structural fatigue and damage. Although TLP foundations can be installed and commissioned onshore, their offshore installation process remains complex, requiring precise tension control and anchoring systems. The installation process is highly challenging, the technology is relatively immature, and a custom-designed installation vessel is necessary.

[0005] In comparison, semi-submersible offshore wind turbine foundations have significant advantages in terms of stability and technological maturity. Semi-submersible floating wind turbine foundations offer good stability, flexible movement, and reliable operation. They are suitable for a wide range of water depths, have a small draft, a large waterline, are movable and reusable, and are easy to install. After near-shore commissioning, they can be towed to the wind farm for anchoring, making them one of the most promising foundations for future offshore wind energy development. However, semi-submersible offshore wind turbine foundations rely on buoyancy for stability. As water depth increases, the buoyancy and stability of the foundation may be affected, especially under extreme weather conditions. Waves and wind can cause the foundation to float and tilt. Furthermore, semi-submersible foundations are typically designed for specific operating conditions, thus their adaptability may be limited in different water depths or extreme environments.

[0006] Therefore, developing a semi-submersible offshore wind power foundation and its application method that can effectively adapt to different water depths or environments and has good stability is a current challenge in the development of marine power generation technology. Summary of the Invention

[0007] In view of the shortcomings mentioned in the above technical background, the purpose of this invention is to provide a floating offshore wind power foundation with ballast that is adapted to water depth and a method of using it.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] A depth-adaptive suspended ballast floating offshore wind turbine foundation includes a three-column semi-submersible foundation for supporting the wind turbine, a mooring system, and a control system for automated control of the wind turbine foundation. The three-column semi-submersible foundation includes three vertical columns, struts, and a ballast caisson. The three vertical columns are equally spaced to form an equilateral triangle. The two ends of the struts are connected to adjacent vertical columns. The ballast caisson is located at the midpoint of the equilateral triangle and is connected to a slide rail on the side wall of the vertical column via a cable. The control system controls the cable to slide up and down relative to the slide rail, thereby moving the ballast caisson up and down relative to the vertical column. The mooring system includes a mooring cable and a mooring anchor corresponding to each vertical column. One end of the mooring cable is fixedly installed at the bottom of the vertical column, and the other end is connected to the mooring anchor, which is anchored to the seabed.

[0010] As a preferred embodiment of the present invention, the bottom of the ballast caisson is provided with a heave plate with an adaptive telescopic width.

[0011] As a preferred technical solution of the present invention, the ballast caisson adopts a concrete cylindrical structure. The control system controls the movement distance of the ballast caisson relative to the vertical column by controlling the movement distance of the cable on the slide rail, thereby completing the center of gravity adjustment of the three-column semi-submersible foundation.

[0012] As a preferred technical solution of the present invention, the ballast caisson adopts a hydraulic tank structure. The hydraulic tank injects or discharges seawater into or out of the hydraulic tank through a hydraulic pump electrically connected to the control system, thereby changing the weight and buoyancy of the hydraulic tank and enabling the ballast caisson to move up and down relative to the vertical column. Pressure sensors are provided on both the inside and outside of the hydraulic tank to monitor the depth of the seawater and the changes in the water pressure inside the hydraulic tank in real time.

[0013] As a preferred embodiment of the present invention, the mooring cable is a catenary steel anchor chain, and the mooring anchor is a suction cylinder anchor or a caisson anchor.

[0014] As a preferred embodiment of the present invention, the support rod includes a horizontal support rod and a diagonal support rod. The top end of each vertical column is connected to the top end of the adjacent vertical column through the horizontal support rod, the bottom end of each vertical column is connected to the bottom end of the adjacent vertical column through the horizontal support rod, and the bottom end of each vertical column is connected to the top end of the adjacent vertical column through the diagonal support rod.

[0015] As a preferred technical solution of the present invention, the control system includes a monitoring subsystem and a control subsystem. The monitoring subsystem monitors wind speed and direction information in real time through ultrasonic wind speed and direction sensors installed on the three-column semi-submersible foundation and feeds it back to the control system. The control system analyzes the wind speed and direction information and issues dynamic control commands to the control subsystem. The control subsystem adjusts the distance between the ballast caisson and the vertical columns according to the commands.

[0016] The present invention discloses a method for using a suspended ballast floating offshore wind turbine foundation adapted to water depth, the method comprising the following steps:

[0017] S1 Monitoring Environmental Conditions: The wind speed and direction around the wind power foundation are monitored in real time using an ultrasonic wind speed and direction sensor, and the monitoring data is transmitted to the control system.

[0018] S2 Calculation of Overturning Moment: The control system calculates the wind force on the wind turbine foundation based on the monitoring data, and calculates the overturning moment M generated by the wind force based on the point of application of the wind force and the center of gravity of the wind turbine foundation. t It satisfies the following relationship:

[0019]

[0020] M t =F w ·d

[0021] In the formula, F w Let ρ be the wind force, ρ be the air density, A be the area affected by the wind (i.e., the projected area of ​​the wind turbine blades), and C be the area of ​​the wind turbine blades. d Where V is the drag coefficient, V is the wind speed, and d is the horizontal distance from the point of wind action to the center of gravity of the wind turbine foundation.

[0022] S3 Calculation of Overturning Moment: The overturning moment M is calculated based on the gravity of the wind turbine foundation and the submersion depth of the ballast caisson. a It satisfies the following relationship:

[0023] M a =μ·W·h

[0024] In the formula, W is the weight of the wind turbine foundation, h is the vertical distance from the center of gravity of the wind turbine foundation to its bottom, and μ is the safety factor, which is less than 1.0.

[0025] S4 Adjust the depth of the ballast caisson: The control system analyzes and judges whether the wind power foundation is safe based on the calculation results of steps S2 and S3. When M t ≥M a If the system determines that the situation is unsafe, it adjusts the depth of the ballast caisson using ziplines and rails until it reaches M. t <M a The adjusted depth h' of the ballast caisson satisfies the following relationship:

[0026] h' = h + d box

[0027] M a ′=μ·W·h′

[0028] M a ′>M t

[0029] In the formula, d box M represents the required additional depth for the ballast caisson. a ' is the overturning moment of the wind power foundation after the ballast caisson is adjusted to a depth h';

[0030] S5 Data Recording and Analysis: Archives all monitoring data, calculation results, and adjustment records for subsequent analysis and optimization of the design and operation of the wind power foundation. Through data analysis, potential risk factors can be identified, providing a reference for future wind power projects.

[0031] As a preferred embodiment of the present invention, the overturning moment in step S2 further includes the overturning moment generated by wave load, satisfying the following relationship:

[0032] M s =M t +M w

[0033] M w =ρ'·g·H·A'·d'

[0034] In the formula, M s M is the total overturning moment experienced by the wind turbine foundation. w Let ρ' be the overturning moment generated by the wave load, A' be the density of seawater, H be the wave area, and d' be the horizontal distance from the point of application of the wave load to the center of gravity of the wind turbine foundation.

[0035] As a preferred embodiment of the present invention, the safety factor μ is set to 0.6.

[0036] In summary, the beneficial effects of this invention are:

[0037] This invention utilizes ballast caissons within wind turbine foundations, whose depth can be adjusted according to real-time marine environmental conditions. This allows the wind turbine foundations to maintain optimal stability and anti-overturning capability under various conditions. In deep-sea areas, wave, tide, and wind variations are significant. The loads and dynamic responses experienced by wind turbine foundations differ depending on water depth and environmental conditions. By adjusting the depth of the ballast caissons, the buoyancy and stability of the wind turbine foundation are improved, enabling it to adapt to a wider range of water depth variations, especially in environments with large fluctuations or strong winds. This avoids the inadequacies of fixed structures, reduces the vibration amplitude of the foundation structure under wave and wind forces, and thus reduces structural fatigue damage. Furthermore, this dynamic adjustment mechanism not only enhances the adaptability and safety of the wind turbine foundation but also reduces overly conservative design and construction, avoiding overly complex structural designs. For example, in shallower waters, excessively large ballast caissons are unnecessary; while in deeper waters, increasing the caisson depth enhances stability. This allows for rational resource allocation based on actual needs, saving construction costs.

[0038] By calculating the overturning moment, it is possible to ensure that the center of gravity and center of buoyancy of the wind power foundation remain in the right position, effectively predict whether the wind power foundation will overturn due to external waves, wind or other factors, take measures in advance to adjust the sinking depth, reduce the risk of wind power foundation overturning, and ensure that the wind power foundation can operate safely under various environmental conditions. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the three-column semi-submersible foundation of the present invention;

[0040] Figure 2 This is a schematic diagram of a suspended ballast floating offshore wind power foundation adapted to water depth according to the present invention;

[0041] Figure 3 This is a flowchart of a method for using a suspended ballast floating offshore wind power foundation adapted to water depth according to the present invention.

[0042] Among them: 1-Three-column semi-submersible foundation, 11-Vertical column, 12-Strut, 13-Ballast caisson, 14-Slip cable, 15-Slip rail, 2-Mooring system, 21-Mooring cable, 22-Mooring anchor. Detailed Implementation

[0043] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments given herein are for illustration and explanation only and are not intended to limit the present invention.

[0044] It should be noted that many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may have other embodiments and variations thereof. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0045] like Figures 1 to 2 As shown, this invention discloses a suspended ballast floating offshore wind turbine foundation adapted to water depth, comprising a three-column semi-submersible foundation 1 for supporting the wind turbine, a mooring system 2, and a control system (not shown) for automated control of the wind turbine foundation. The three-column semi-submersible foundation 1 includes three vertical columns 11, struts 12, and ballast caissons 13. The three vertical columns 11 are equally spaced to form an equilateral triangle. The two ends of the struts 12 are respectively connected to the adjacent vertical columns 11. The ballast caissons 13 are located at the midpoint of the equilateral triangle and are connected to the slide rails 15 set on the side walls of the vertical columns 11 via a cable 14. The control system controls the cable 14 to slide up and down relative to the slide rails 15, so that the ballast caissons 13 move up and down relative to the vertical columns 11. The mooring system 2 includes mooring cables 21 and mooring anchors 22 corresponding to the vertical columns 11. One end of the mooring cable 21 is fixedly installed at the bottom of the vertical column 11, and the other end is connected to the mooring anchor 22, which is anchored to the seabed.

[0046] By adjusting the vertical movement of the ballast caisson 13 relative to the vertical column 11 through the control system, the center of gravity and draft of the foundation can be effectively adjusted. The stability of the foundation can be adjusted in real time according to different environmental conditions, such as wave, wind speed, and tidal changes, ensuring that the wind turbine foundation maintains optimal stability and anti-overturning capability under various conditions. Especially in deep water and dynamic environments, the vertical adjustment of the ballast caisson 13 optimizes the buoyancy and stability of the wind turbine foundation, avoiding instability caused by excessive or insufficient buoyancy and reducing the risk of damage in extreme weather or severe sea conditions. Secondly, by adjusting the depth of the ballast caisson 13, not only can the stability of the wind turbine foundation be adjusted, but the stress on the mooring system 2 can also be optimized. The mooring cable 21 and anchoring system are key to ensuring the stability of the floating foundation. By controlling the position of the ballast caisson 13, the mechanical state of the mooring system 2 can be optimized under different sea conditions, making the stress on the mooring cable 21 more uniform, avoiding overload or instability of the mooring system 2, thereby improving the reliability of the entire system.

[0047] In a preferred embodiment of the present invention, the bottom of the ballast caisson 13 is provided with a heave plate with an adaptive telescopic width.

[0048] The adaptive telescopic width function of the heave plate can automatically adjust according to changes in the sea waves to provide appropriate hydrodynamic damping, which helps to counteract the aerodynamic thrust generated by the wind turbine, enhances the ability of the wind power foundation to resist unstable airflow in the deep sea area, effectively reduces the impact of the ocean current on the ballast caisson 13, reduces the amplitude of the platform's sway and heave, and enables the ballast caisson 13 to maintain a more stable dynamic equilibrium state, thereby reducing the swaying and uneven stress phenomenon of the wind power foundation and improving the performance and stability of the wind power foundation in complex marine environments.

[0049] As a preferred embodiment of the present invention, the ballast caisson 13 adopts a concrete cylindrical structure. The control system controls the movement distance of the ballast caisson 13 relative to the vertical column 11 by controlling the movement distance of the zipline 14 on the slide rail 15, thereby completing the center of gravity adjustment of the three-column semi-submersible foundation 1.

[0050] The concrete cylindrical structure maintains stability through the balance of its own weight and the buoyancy of water. Concrete material has good compressive strength and durability, and can withstand greater external pressure and environmental impact, making it suitable for use in harsh environments such as the ocean. Its large self-weight and strong anti-buoyancy capacity in water effectively maintain the stability of the caisson. The control system drives the sliding cable 14 to move on the sliding rail 15, thereby moving the ballast caisson 13 up and down. The working mechanism and structural design are simple, reducing complex mechanical parts, resulting in a low failure rate and relatively less maintenance and repair requirements, thus reducing long-term operating costs. It can operate stably under different environmental conditions, has strong adaptability, and is suitable for a variety of application scenarios.

[0051] As a preferred embodiment of the present invention, the ballast caisson 13 adopts a hydraulic tank structure. The hydraulic tank injects or discharges seawater into or out of the hydraulic tank through a hydraulic pump electrically connected to the control system, thereby changing the weight and buoyancy of the hydraulic tank and completing the up-and-down movement of the ballast caisson 13 relative to the vertical column 11. Pressure sensors are provided on both the inside and outside of the hydraulic tank to monitor the depth of the seawater and the changes in the water pressure inside the hydraulic tank in real time.

[0052] The ballast caisson 13 changes its buoyancy by adjusting the fluid entering the hydraulic tank, thereby controlling its weight and depth in the water. When a deeper submersion is needed for greater stability, the water volume in the hydraulic tank is increased to deepen the caisson 13's submersion depth, ensuring the wind power platform maintains an ideal stable state. Precise position control of the ballast caisson 13 is achieved through hydraulic pump control, making it suitable for applications requiring high-precision positioning. It can complete position adjustments quickly, making it suitable for applications in dynamic environments.

[0053] In a preferred embodiment of the present invention, the mooring cable 21 is a catenary steel anchor chain, and the mooring anchor 22 is a suction cylinder anchor or a caisson anchor.

[0054] In a preferred embodiment of the present invention, the strut 12 includes a horizontal strut and a diagonal strut. The top end of each vertical column 11 is connected to the top end of the adjacent vertical column 11 by a horizontal strut, the bottom end of each vertical column 11 is connected to the bottom end of the adjacent vertical column 11 by a horizontal strut, and the bottom end of each vertical column 11 is connected to the top end of the adjacent vertical column 11 by a diagonal strut.

[0055] In a preferred embodiment of the present invention, the control system includes a monitoring subsystem and a control subsystem. The monitoring subsystem monitors wind speed and direction information in real time through an ultrasonic wind speed and direction sensor installed on the three-column semi-submersible foundation 1 and feeds it back to the control system. The control system analyzes the wind speed and direction information and issues dynamic control commands to the control subsystem. The control subsystem adjusts the distance between the ballast caisson 13 and the vertical column 11 according to the commands.

[0056] like Figure 3 As shown, the present invention discloses a method for using a suspended ballast floating offshore wind turbine foundation adapted to water depth. The method includes the following steps:

[0057] S1 monitors environmental conditions: It uses ultrasonic wind speed and direction sensors to monitor the wind speed and direction around the wind power foundation in real time and transmits the monitoring data to the control system.

[0058] S2 calculates the overturning moment: The control system calculates the wind force on the wind turbine foundation based on monitoring data. Based on the point of application of the wind force and the center of gravity of the wind turbine foundation, it calculates the overturning moment M generated by the wind force. t It satisfies the following relationship:

[0059]

[0060] M t =F w ·d

[0061] In the formula, F w Let ρ be the wind force, ρ be the air density, A be the area affected by the wind (i.e., the projected area of ​​the wind turbine blades), and C be the area of ​​the wind turbine blades. d denoted as drag coefficient, V as wind speed, and d as the horizontal distance from the point of wind action to the center of gravity of the wind turbine foundation.

[0062] S3 Calculation of Overturning Moment: The overturning moment M is calculated based on the gravity of the wind turbine foundation and the submersion depth of the ballast caisson 13. a It satisfies the following relationship:

[0063] M a=μ·Wxh

[0064] In the formula, W is the weight of the wind turbine foundation, h is the vertical distance from the center of gravity of the wind turbine foundation to its bottom, and μ is the safety factor, which is 0.6.

[0065] S4 Adjust the depth of the ballast caisson 13: The control system analyzes and judges whether the wind turbine foundation is safe based on the calculation results of steps S2 and S3. When M t ≥M a If the system determines that the situation is unsafe, it adjusts the depth of the ballast caisson 13 via the cableway 14 and the rail 15 until it reaches M. t <M a The adjusted depth h' of the ballast caisson 13 satisfies the following relationship:

[0066] h' = h + d box

[0067] M a ′=μ·W·h′

[0068] M a ′>M t

[0069] In the formula, d box To increase the depth required for ballast caisson 13, M a ' is the overturning moment of the wind turbine foundation after the depth h' of the ballast caisson 13 is adjusted;

[0070] S5 Data Recording and Analysis: Archives all monitoring data, calculation results, and adjustment records for subsequent analysis and optimization of wind power foundation design and operation. Through data analysis, potential risk factors can be identified, providing a reference for future wind power projects.

[0071] This invention, by calculating the overturning moment, ensures that the center of gravity and center of buoyancy of the wind turbine foundation remain in the appropriate positions. It effectively predicts whether the foundation will overturn due to external waves, wind, or other factors, allowing for proactive adjustments to the settling depth and reducing the risk of overturning. This ensures safe operation of the wind turbine foundation under various environmental conditions. Precise calculation of the required settling depth reduces the possibility of over-design and avoids unnecessary excessive settling of the caisson, thereby lowering construction and maintenance costs.

[0072] In a preferred embodiment of the present invention, the overturning moment in step S2 also includes the overturning moment generated by the wave load, which satisfies the following relationship:

[0073] M s =M t +M w

[0074] M w=ρ'·g·H·A'·d'

[0075] In the formula, M s M is the total overturning moment experienced by the wind turbine foundation. w Let ρ' be the overturning moment generated by the wave load, A' be the density of seawater, H be the wave area, and d' be the horizontal distance from the point of application of the wave load to the center of gravity of the wind turbine foundation.

[0076] It should be understood that the above embodiments are one or more embodiments of the present invention, and there are many other embodiments and variations based on the present invention; any variations and modifications made by those skilled in the art through the present invention without making pioneering innovations are all within the protection scope of the present invention.

Claims

1. A floating offshore wind foundation of the suspended ballast type adapted to water depths, characterized in that, The application relates to a three-column semi-submersible foundation for supporting a wind turbine, a mooring system and a control system for automatically controlling the wind power foundation. The three-column semi-submersible foundation comprises three vertical columns, a bracing rod and a ballast tank, the three vertical columns are equidistantly arranged and form an equilateral triangle, the bracing rod comprises horizontal bracing rods and inclined bracing rods, the top end of each vertical column is connected with the top end of an adjacent vertical column through the horizontal bracing rod, the bottom end of each vertical column is connected with the bottom end of an adjacent vertical column through the horizontal bracing rod, and the bottom end of each vertical column is connected with the top end of an adjacent vertical column through the inclined bracing rod. The ballast tank is arranged at the midpoint of the equilateral triangle and is connected with sliding rails arranged on the side walls of the vertical columns through sliding ropes, and the ballast tank adopts a concrete cylindrical structure or a hydraulic chamber structure. The control system comprises a monitoring subsystem and a control subsystem, the monitoring subsystem monitors wind speed and direction information in real time through ultrasonic wind speed and direction sensors arranged on the three-column semi-submersible foundation and feeds back the information to the control system, the control system analyzes the wind speed and direction information and sends dynamic control commands to the control subsystem, and the control subsystem adjusts the distance between the ballast tank and the vertical columns according to the commands to dynamically adjust the center of gravity position and draft of the three-column semi-submersible foundation. When the ballast tank adopts the concrete cylindrical structure, the control system controls the moving distance of the sliding ropes on the sliding rails and then controls the moving distance of the ballast tank relative to the vertical columns. When the ballast tank adopts the hydraulic chamber structure, the hydraulic chamber injects or discharges seawater into or out of the interior of the hydraulic chamber through a hydraulic pump electrically connected with the control system to change the weight and buoyancy of the hydraulic chamber, thereby achieving the up-down movement of the ballast tank relative to the vertical columns, and the interior and the outer wall of the hydraulic chamber are respectively provided with pressure sensors for monitoring the depth of seawater and the change of water pressure in the hydraulic chamber in real time. The mooring system comprises mooring cables and mooring anchors corresponding to the vertical columns one by one, one end of the mooring cable is fixedly installed at the bottom of the vertical column, the other end is connected with the mooring anchor, and the mooring anchor is anchored to the seabed. The bottom of the ballast tank is provided with a heave plate with self-adapting and retracting width.

2. The depth-adapted suspended weight-based floating offshore wind foundation according to claim 1, characterized in that: The mooring cable adopts a catenary steel anchor chain, and the mooring anchor adopts a suction cylinder anchor or a caisson anchor.

3. The depth-adapted, suspended, ballast-equipped, floating foundation for offshore wind turbines of claim 1, characterized in that: The application further relates to a method for using the three-column semi-submersible foundation for supporting a wind turbine, the method comprising the following steps:

4. A method of using a floating offshore wind power foundation of the suspended ballast type adapted to water depths, characterized in that: S1 monitoring environmental conditions: using ultrasonic wind speed and direction sensors to monitor the wind speed and direction around the wind power foundation in real time and transmitting monitoring data to the control system; S5 data recording and analysis: archiving all monitoring data, calculation results and adjustment records for subsequent analysis and optimization of the design and operation of the wind power foundation, and identifying potential risk factors through data analysis and providing references for future wind power projects. S2 calculates overturning moment: the control system calculates the wind force on the wind power foundation according to the monitoring data, and calculates the overturning moment M generated by the wind force based on the action point of the wind force and the position of the center of gravity of the wind power foundation t , and satisfies the following relationship: where F w is the wind force, p is the air density, A is the wind action area, i.e. the projected area of the wind turbine blades, C d is the wind resistance coefficient, V is the wind speed, and d is the horizontal distance from the wind action point to the center of gravity of the wind power foundation. S3 calculating the overturning moment: calculating the overturning moment M according to the weight of the wind power foundation and the submerged depth of the ballast caisson a , which satisfies the following relationship: wherein W is the weight of the wind power foundation, h is the vertical distance from the center of gravity of the wind power foundation to its bottom, and μ is a safety factor, which is less than 1.

0. S4: Adjust the depth of the ballast caisson: the control system analyzes and judges whether the wind power foundation is safe according to the calculation results of steps S2 and S3, when M t ≥ M a , it is judged as unsafe, the control system adjusts the depth of the ballast caisson through the slide and slide rail until M t < M a , wherein the adjusted depth h' of the ballast caisson satisfies the following relationship: where d box M is the depth needed to be added to the ballast caisson, M a M' is the overturning moment of the wind power foundation after the ballast caisson is adjusted to the depth h' ​ 5. A method of using a floating offshore wind foundation of the adaptive water depth suspended ballasted type according to claim 4, characterized in that: The overturning moment in step S2 also includes an overturning moment generated by a wave load, and satisfies the following relationship: where M s is the total overturning moment experienced by the wind turbine foundation, M w is the overturning moment due to wave loads, p' is the density of sea water, A' is the wave action area, H is the wave height, and d' is the horizontal distance from the wave load action point to the center of gravity of the wind turbine foundation.

6. A method of using an adaptive water depth suspended weight based floating offshore wind foundation according to claim 4, characterized in that: The safety factor μ is 0.6.

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