Flywheel energy storage tension leg type fan foundation capable of improving stability

Abstract

The utility model discloses a flywheel energy storage tension leg type fan foundation capable of improving stability, the fan foundation comprises a floating body structure, a flywheel energy storage system and a mooring device, the floating body structure is arranged below a wind turbine generator, and the floating body structure acts as a traditional tension leg structure and is directly connected with the mooring device. The flywheel energy storage system is arranged in the floating body structure, and through mutual conversion of electric energy and flywheel kinetic energy, whole-course peak regulation of the generated power of the floating type draught fan is achieved. Meanwhile, the flywheels rotating at a high speed have the gyroscopic effect, the output torque generated by rotation of the flywheels can be used for resisting the horizontal load action of wind, waves, flow and the like, and swing of the floating fan is reduced. And therefore, the influence of the wake effect on the power generation efficiency of the floating fan can be reduced, and the influence of swinging on the structural stability of the fan can be avoided.

Description

Technical Field

[0001] The utility model relates to a flywheel energy storage tension leg type wind turbine foundation with improved stability, belonging to the field of offshore floating wind turbine generator sets and marine energy storage devices. Background Art

[0002] Due to the unstable wind speed, wind power generation has strong volatility and intermittency, which makes the frequency stability problem of the power system more serious and the demand for peak load regulation of the power grid is increasing. The traditional peak load regulation method mainly relies on thermal power generation, but large-scale thermal power generation systems cannot be deployed in offshore wind farms.

[0003] In addition, offshore floating wind turbines are susceptible to irregular swings due to the influence of wind, waves, and currents. On the one hand, the swing will cause the blades to enter the wake area where the wind speed decreases, thereby reducing the power generation efficiency; on the other hand, the swing may also cause the blades and structures to fail or even capsize. Wind turbine sway reduction has become one of the key issues for offshore floating wind turbines. Feasible sway reduction methods include heave plates, sway reduction tanks, and additional dampers, but the current sway reduction solutions with mature technology, good sway reduction effects, and low costs are difficult to promote. In summary, the problems of wind turbine grid peak regulation and floating wind turbine sway reduction are still prominent, and it is urgent to propose a new floating wind turbine technical solution to solve the above two problems.

[0004] Based on this, the utility model provides a solution based on flywheel energy storage. The flywheel energy storage system is a new type of green energy storage method and a device that realizes the mutual conversion of kinetic energy and electrical energy. That is, when storing energy, the motor drives the flywheel to rotate at high speed, so the electrical energy is converted into kinetic energy and stored; when discharging, the high-speed rotating flywheel drives the generator to run and convert the kinetic energy into electrical energy. Compared with other power grid peak regulation solutions, such as supercapacitors, superconducting magnetic energy storage, and pumped storage, the flywheel has a large energy storage capacity and a response speed of milliseconds. It has the characteristics of long continuous energy release time and fast response time, which can effectively smooth the output power of the wind farm; and the flywheel of the flywheel energy storage system produces a shedding effect when working, which can achieve shake reduction. Utility Model Content

[0005] The utility model aims to provide a flywheel energy storage tension leg wind turbine foundation with improved stability, so as to solve the problem of fluctuation of output power of offshore floating wind turbines and the swaying problem of the structure itself in the above-mentioned background technology.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A flywheel energy storage tension leg wind turbine foundation with improved stability, the wind turbine foundation comprising a floating structure, a flywheel energy storage system and a mooring device; the floating structure comprises a connected column and a lower buoy; one end of the mooring device (4) is fixed on the seabed, and the other end is fixed to the floating structure (2); the mooring device (4) comprises three anchors (402) arranged on the seabed around the lower buoy (202); the upper end of the column is used to set a wind turbine; the flywheel energy storage system is arranged in the floating structure; the flywheel energy storage system comprises an outer shell; the outer shell is a hollow cylinder fixed in the floating structure.

[0008] Furthermore, the flywheel energy storage system also includes a first bearing, an axis core, an electric motor / generator, a vacuum pump, a flywheel and a second bearing; the first bearing and the second bearing are respectively arranged on the upper surface and the lower surface of the shell; the two ends of the axis core are respectively arranged on the first bearing and the second bearing, and the connecting line of the three is located on the central axis of the shell; the electric motor / generator and the flywheel pass through the axis core in sequence from top to bottom; the vacuum pump is arranged on the shell to evacuate the vacuum chamber.

[0009] Furthermore, the housing is composed of two connected cylinders, one thinner on the top and thicker on the bottom. The upper cylinder just accommodates the electric motor / generator, and the lower cylinder accommodates the flywheel.

[0010] Furthermore, the floating structure is similar in shape to the flywheel energy storage system, wherein the dimensions of the upright column and the lower buoy are just able to accommodate the upper cylinder and the lower cylinder.

[0011] Furthermore, the mooring device includes three mooring anchor chains and three anchors arranged on the seabed around the lower buoy as the center, and one end of all the mooring anchor chains is evenly fixed to the outer edge of the bottom of the lower buoy, and the other end is respectively fixed to the corresponding anchor.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] (1) A flywheel energy storage system is installed in the foundation of the tension leg floating wind turbine. Through the mutual conversion of electrical energy and flywheel kinetic energy, the output power of the entire system is adjusted to achieve full peak regulation. Compared with peak regulation methods such as thermal power generation or electrochemical energy storage, flywheel energy storage has a large capacity and a response speed of milliseconds. It has the advantages of long continuous energy release time and fast response time.

[0014] (2) A flywheel energy storage system is installed in the foundation of the tension leg floating wind turbine. A large-diameter buoy is used to replace the traditional tension leg structure to connect the mooring device. The large-diameter buoy provides space for arranging a large-diameter flywheel. The large-diameter flywheel has a larger moment of inertia and can store more kinetic energy at the same speed.

[0015] (3) A flywheel energy storage system is installed in the foundation of the tension-leg floating wind turbine. The flywheel rotates at high speed around the vertical axis, thereby generating a gyroscopic effect. Therefore, the output torque generated by the rotation of the flywheel can be used to resist horizontal loads such as wind, waves, and currents, and reduce the sway of the floating wind turbine. This can reduce the impact of the "wake effect" on the power generation efficiency of the floating wind turbine, and avoid the impact of sway on the structural stability of the wind turbine.

[0016] (4) The flywheel energy storage system has a huge mass and is distributed at the bottom of the floating structure, which effectively lowers the center of gravity of the floating wind turbine system and improves the stability of the floating structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of the tension leg fan of the utility model embodiment;

[0018] Figure 2 This is a cross-sectional view of the foundation of the tension leg fan of the utility model embodiment;

[0019] Figure 3 This is a cross-sectional view of a buoy in an embodiment of the utility model;

[0020] Figure 4 A top view of a flywheel energy storage system according to an embodiment of the utility model;

[0021] Figure 5 This is a three-dimensional schematic diagram of the AA section of the flywheel energy storage system according to an embodiment of the utility model;

[0022] Figure 6 This is a side view of the AA section of the flywheel energy storage system according to an embodiment of the utility model;

[0023] Figure 7 It is a schematic diagram of the overall structure of a traditional tension leg wind turbine;

[0024] In the figure: 1. wind turbine; 2. floating structure; 201. column; 202. lower buoy; 3. flywheel energy storage system; 301. housing; 302. first bearing; 303. shaft core; 304. electric / generator; 305. vacuum chamber; 306. vacuum pump; 307. flywheel; 308. second bearing; 4. mooring device; 401. mooring anchor chain; 402. anchor. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. The utility model is a wind turbine foundation for a floating wind turbine. The floating wind turbine generally includes a wind turbine set 1 and a wind turbine foundation. The wind turbine set 1 is arranged on the wind turbine foundation.

[0026] A flywheel energy storage tension leg type wind turbine foundation with improved stability realizes wind turbine sway reduction, energy storage and peak regulation.

[0027] Based on the above requirements, a flywheel energy storage tension leg wind turbine foundation with improved stability is provided, wherein the wind turbine foundation comprises a floating structure 2, a flywheel energy storage system 3 and a mooring device 4; one end of the mooring device 4 is fixed to the seabed, and the other end is fixed to the floating structure 2; the floating structure 2 comprises a connected column 201 and a lower buoy 202; the column 201 is used to set up a wind turbine set 1; the flywheel energy storage system 3 is set on the floating structure 2.

[0028] Example: See Figure 1-3 The utility model provides a technical solution: a flywheel energy storage tension leg wind turbine foundation with improved stability, comprising a floating structure 2, a flywheel energy storage system 3 and a mooring device 4. The floating structure 2 is arranged below the wind turbine 1. The floating structure 2 is divided into a column 201 and a lower buoy 202 connected up and down. The diameter of the lower buoy 202 is much larger than the diameter of the column 201. The shape of the flywheel energy storage system 3 is similar to that of the floating structure 2, and its outer dimensions match the inner dimensions of the buoy 2. The flywheel energy storage system 3 is arranged on the bottom surface of the lower buoy 202, and the cylindrical protrusion on the upper part enters the interior of the column 201. The mooring device 4 includes three mooring anchor chains 401 and three anchors 402 fixed on the seabed. The upper end of each mooring anchor chain 401 is respectively fixed to the outer edge of the bottom of the lower buoy 202, and the lower end is respectively fixed to the anchor 402.

[0029] like Figure 3 The column 201 and the lower buoy 202 are double cylindrical components that are sealed on the outside and connected on the inside. While providing buoyancy for the wind turbine 1, they are also used to arrange the flywheel energy storage system 3.

[0030] like Figure 3 and 7 The diameter of the lower buoy 202 is equivalent to the spacing of the tension legs of the traditional tension leg type wind turbine foundation. The lower buoy 202 replaces the traditional tension legs and is used to connect the upper end of the mooring anchor chain 401. Three fixing points of the mooring anchor chain 401 are provided at the bottom of the lower buoy 202.

[0031] like Figure 3-6The flywheel energy storage system 3 is composed of a housing 301, a first bearing 302, a shaft core 303, an electric motor / generator 304, a vacuum chamber 305, a vacuum pump 306, a flywheel 307 and a second bearing 308. The housing 301 is evacuated by a vacuum pump 306 disposed inside the housing 301 to form a vacuum chamber 305, so as to reduce the resistance to the rotation of the flywheel 307 and improve the energy conversion efficiency. The column 201 has a small diameter and is used to arrange the electric motor / generator 304; the lower buoy 202 has a large diameter and is used to arrange the flywheel 307. The flywheel 307 is connected to the electric motor / generator 304 through the shaft core 303 and is supported by the first bearing 302 and the second bearing 308.

[0032] The kinetic energy of the flywheel 307 when it rotates is:

[0033]

[0034] Wherein, J is the moment of inertia of the flywheel 307, and ω is the angular velocity of the flywheel 307. Since the lower buoy 202 has a large diameter, it provides space for arranging a large-diameter flywheel 307, thereby increasing the mass and diameter of the flywheel 307 to increase its moment of inertia, thereby increasing the energy storage density of the flywheel 307. The flywheel energy storage system has a huge mass and is distributed at the bottom of the floating structure, which effectively reduces the center of gravity of the floating wind turbine and improves the stability of the floating structure.

[0035] Due to the gyroscopic effect, the flywheel 307 naturally forms a gyroscopic anti-roll device while rotating at high speed. The output torque generated by the rotation of the flywheel 307 can be used to resist horizontal loads such as wind, waves, and currents, thereby reducing the sway of the wind turbine 1, thereby reducing the impact of the "wake effect" on the power generation efficiency of the floating wind turbine and avoiding the impact of the sway on the structural stability of the wind turbine. Working principle:

[0036] The flywheel energy storage tension leg wind turbine foundation with improved stability realizes grid peak regulation, and the specific working principle is as follows: the electric / generator 304 is both a motor and a generator. When the power generation of the wind turbine set 1 decreases, it acts as a generator to convert the kinetic energy of the high-speed rotating flywheel 307 into electrical energy; when the power generation of the wind turbine set 1 increases, it acts as a motor to convert the electrical energy into kinetic energy of the flywheel 307 for storage.

[0037] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the ideas and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flywheel energy storage tension leg wind turbine foundation with improved stability, characterized in that: The wind turbine foundation comprises a floating structure (2), a flywheel energy storage system (3) and a mooring device (4); The floating structure (2) comprises a connected column (201) and a lower buoy (202); One end of the mooring device (4) is fixed on the seabed, and the other end is fixed to the floating structure (2); the mooring device (4) comprises three anchors (402) arranged on the seabed around the lower buoy (202); The upper end of the column (201) is used to arrange the wind turbine generator set (1); The flywheel energy storage system (3) is arranged in the floating structure (2); the flywheel energy storage system (3) comprises an outer shell (301); the outer shell (301) is a cylindrical body with a hollow interior and is fixed in the floating structure (2).

2. The flywheel energy storage tension leg wind turbine foundation with improved stability according to claim 1, characterized in that: The flywheel energy storage system (3) further comprises a first bearing (302), a shaft core (303), a motor / generator (304), a vacuum pump (306), a flywheel (307) and a second bearing (308); The first bearing (302) and the second bearing (308) are respectively arranged on the upper surface and the lower surface of the housing (301); The two ends of the shaft core (303) are respectively arranged on the first bearing (302) and the second bearing (308), and the connecting line of the three is located on the central axis of the housing (301); The motor / generator (304) and the flywheel (307) are arranged sequentially through the shaft core (303) from top to bottom; The vacuum pump (306) is disposed on the housing (301) and is used to evacuate the vacuum chamber (305).

3. The flywheel energy storage tension leg wind turbine foundation with improved stability according to claim 2, characterized in that: The housing (301) is composed of two connected cylinders, one thinner on the top and thicker on the bottom. The upper cylinder is used to accommodate the motor / generator (304), and the lower cylinder is used to accommodate the flywheel (307).

4. The flywheel energy storage tension leg wind turbine foundation with improved stability according to claim 3, characterized in that: The floating structure (2) is similar in shape to the flywheel energy storage system (3), wherein the dimensions of the upright column (201) and the lower buoy (202) are just able to accommodate the upper cylinder and the lower cylinder.

5. The flywheel energy storage tension leg wind turbine foundation with improved stability according to claim 1, characterized in that: The mooring device (4) comprises three mooring anchor chains (401), one end of each of the mooring anchor chains (401) is evenly fixed to the outer edge of the bottom of the lower buoy (202), and the other end is respectively fixed to the corresponding anchor (402).

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