Floating fan with anti-rolling function and control method thereof

Abstract

The invention discloses a floating fan with a stabilization function and a control method of the floating fan. A wind turbine unit of the floating fan is installed at the top end of a tower, the bottom end of the tower is installed on a floating platform, a plurality of stabilization rudders are arranged on the outer side face of the floating platform, and the floating platform floats on the sea surface and is connected to a seabed through a plurality of mooring chains. The method comprises the steps that a control system controls all rudder wings of the floating fan in real time according to a tilt angle monitored by a sensor in real time and a preset expected tilt angle, different working states are switched to achieve continuous control over the wave energy device, and when the tilt angle of the floating fan does not exceed the expected tilt angle, the floating fan does not start a stabilization rudder, and an automatic stabilization mode is started; and when the inclination angle of the floating fan exceeds the expected inclination angle, stabilization is carried out by controlling the rudder wings. According to the invention, the purposes of stabilizing the floating fan and saving energy can be achieved, so as to cope with complex sea conditions and prolong the working time.

Description

Technical Field

[0001] The invention belongs to the field of offshore wind power, and in particular relates to a floating wind turbine with a sway reduction function and a control method thereof. Background Art

[0003] The deep sea with a water depth of more than 50m contains more abundant wind energy resources, and "offshore" has become the only way for the development of wind power. The cost of traditional fixed foundation wind turbines increases sharply with the water depth, so floating wind turbines suitable for deep sea were born.

[0004] However, when floating wind turbines are operating at sea, they are often affected by complex sea conditions, including wind, waves, currents and other complex factors. Under complex sea conditions, offshore wind turbine platforms will produce violent motion responses, which will have a bad impact on the service life of offshore wind turbines. Therefore, suppressing the motion response of offshore wind turbines is currently a key issue of concern. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention proposes a floating wind turbine with a sway reduction function and a control method thereof, aiming to solve the deficiencies in the prior art.

[0006] The technical solution adopted by the present invention is:

[0007] The present invention comprises a wind turbine, a tower, a floating platform, a roll stabilizer and a plurality of mooring chains. The wind turbine is mounted on the top of the tower, the bottom of the tower is mounted on the floating platform, a plurality of roll stabilizers are arranged on the outer side of the floating platform, the floating platform floats on the sea surface and is connected to the seabed through a plurality of mooring chains.

[0008] The floating platform includes a central column, a floating support unit, a wave-breaking plate and a cross brace. The bottom end of the tower is installed on the central column. The central column is located at the center of a square surrounded by four floating support units. Adjacent floating support units are fixedly connected by wave-breaking plates. The four floating support units are fixedly connected to the central column by cross braces. A roll stabilizer is provided on the outer side of each floating support unit, and each floating support unit and the central column are connected to the seabed by a mooring chain.

[0009] Each floating support unit includes a cylindrical foundation, a side column, a gas heaving swing plate and a U-shaped water tank. The cylindrical foundation is fixedly connected to the central column through a cross brace and a roll stabilizer is provided on the outer side of the cylindrical foundation. The bottom of the cylindrical foundation is fixedly connected to the gas heaving swing plate, the upper end of the cylindrical foundation is fixedly connected to the side column, and a U-shaped water tank is built into the side column. The side columns in adjacent floating support units are fixedly connected by wave-breaking plates, and the cylindrical foundation and the central column are connected to the mooring chain through the fairlead holes arranged on the side wall.

[0010] The U-shaped water tank includes an upper cavity and a lower cavity, which are sealed and fixedly connected to form a cavity inside. The cavity is mainly composed of high-position cavities on both sides and a low-position cavity located between the high-position cavities on both sides. The high-position cavities on both sides and the low-position cavity in the middle are interconnected to form a cavity together.

[0011] The anti-roll rudder comprises a rudder wing, a servo motor, a hydraulic mechanism and a control system. The control system is electrically connected to the servo motor and the hydraulic mechanism respectively. The hydraulic mechanism comprises a hydraulic cylinder and a transmission mechanism. The hydraulic cylinder is connected to the servo motor through the transmission mechanism, and the servo motor is connected to the rudder wing.

[0012] The control system includes a pitch controller, a roll controller and a sensor. The pitch controller is used to control the rudder blades to reduce the pitch of the floating wind turbine; the roll controller is used to control the rudder blades to reduce the roll of the floating wind turbine; and the sensor is used to monitor the movement state of the floating wind turbine in real time.

[0013] The wave-breaking plate is mainly composed of two oppositely arranged fence plates and a wave-breaking column between the two fence plates. The two fence plates are arranged parallel to the sea level. A plurality of wave-breaking columns are arranged in an array between the two fence plates. The wave-breaking columns are perpendicular to the two fence plates and are arranged integrally with the two fence plates. The side columns in adjacent floating support units are fixedly connected by the fence plates and the wave-breaking columns.

[0014] The four U-shaped water tanks are placed symmetrically to the center.

[0015] The control method of the floating wind turbine comprises the following steps:

[0016] Step 1: The floating wind turbine is subjected to the action of wind and waves at sea. Under the action of wind, the wind turbine unit of the floating wind turbine converts mechanical energy into electrical energy to generate electricity in real time, and supplies electricity to the anti-roll rudder;

[0017] Step 2: The sensors on the anti-roll rudder monitor the pitch angle of the floating wind turbine in real time. The pitch angle is divided into two parts: pitch angle and roll angle. The pitch angle is transmitted to the control system of each anti-roll rudder;

[0018] Step 3: The control system controls each rudder blade of the floating wind turbine in real time according to the pitch angle monitored by the sensor in real time and the preset desired pitch angle, so as to realize continuous control of the wave energy device.

[0019] The step 3 is as follows:

[0020] When the control system determines that the pitch angle of the floating wind turbine does not exceed the expected pitch angle, the floating wind turbine does not start the anti-roll rudder, and relies on the U-shaped water tank, air heave plate and wave-breaking plate to passively reduce the roll, and continues to monitor and judge whether the pitch angle of the floating wind turbine exceeds the expected pitch angle.

[0021] When the control system determines that the pitch angle of the floating wind turbine exceeds the expected pitch angle, the floating wind turbine activates the anti-roll rudder, which determines through the control system whether the pitch angle and roll angle are within the expected pitch angle. If they are within the expected pitch angle, the pitch controller and roll controller are controlled to shut down respectively.

[0022] If the expected pitch angle is exceeded, the pitch controller / roll controller deploys the rudder wings through the hydraulic mechanism, and then controls the rudder wings through the servo motor to pitch / roll reduce the floating wind turbine, and then continues to judge whether the floating wind turbine is within the expected pitch angle.

[0023] The beneficial effects of the present invention are:

[0024] (1) The present invention arranges a U-shaped anti-rolling water tank in the column. The double resonance characteristics of the U-shaped anti-rolling water tank can reduce the roll of the device at sea and improve the motion response.

[0025] (2) The columns of the present invention are connected by wave-breaking plates with wave-breaking function. The upper end of the wave-breaking plate is on the free water surface, and the middle and lower ends have a certain diving depth in the water. The wave-breaking plate is mainly composed of two fence plates arranged opposite each other and a wave-breaking column between the two fence plates. The structure of the wave-breaking plate can achieve energy dissipation effect through deformation and reflection of wave propagation. The wave-breaking plate is a hollow structure, which can effectively reduce the force-bearing area of ​​the structure and cause waves to collide inside the structure, thereby dissipating energy and contributing to the stability of the structure. The wave-breaking plate is composed of wave-breaking columns and fence plates with gaps. This design can dissipate the energy of the incident wave in front of the plate, and deform or even break the wave to prevent it from further propagating. In addition, the fence plates and wave-breaking columns in the wave-breaking plate cooperate with each other so that the wave-breaking plate has multiple wave-breaking chambers, thereby optimizing the wave-breaking effect.

[0026] (3) The present invention provides a control system, which is in a shutdown state when the device is within the desired pitch angle. When the device exceeds the desired pitch angle, the controller starts to work, and the roll and pitch controllers judge and operate the desired angles respectively, and then continue to judge the pitch angle, so as to achieve the purpose of secondary roll reduction and energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the device of the present invention;

[0028] Figure 2 It is the cross-section of the column;

[0029] Figure 3 This is the working principle diagram of the U-shaped water tank;

[0030] Figure 4 This is a top view of the device of the present invention without a fan;

[0031] Figure 5This is a schematic diagram of a wave-breaking board;

[0032] Figure 6 is a control flow chart;

[0033] In the figure: 1. wind turbine, 2. tower, 3. central column, 4. cylindrical foundation, 5. side column, 6. air heave plate, 7. wave-breaking plate, 8. cross brace, 9. U-shaped water tank, 10. rudder wing, 11. mooring chain, 12. fairlead hole, 13. fence plate, 14. wave-breaking column. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on it.

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] A floating wind turbine with a sway reduction function Figure 1 As shown, it includes a wind turbine 1, a tower 2, a floating platform, a roll stabilizer and a plurality of mooring chains 11. The wind turbine 1 is installed on the top of the tower 2, and the bottom of the tower 2 is installed on the floating platform. A plurality of roll stabilizers are arranged on the outer side of the floating platform. The floating platform floats on the sea surface and is connected to the seabed through a plurality of mooring chains 11.

[0037] Specifically, the floating platform includes a central column 3, a floating support unit, a wave-breaking plate 7 and a cross brace 8. The bottom end of the tower 2 is installed on the central column 3. The central column 3 is located at the center of a square surrounded by four floating support units. Adjacent floating support units are fixedly connected by wave-breaking plates 7 with wave-breaking function. The four floating support units are fixedly connected to the central column 3 by cross braces 8. A retractable anti-roll rudder is provided on the outer side of each floating support unit, and each floating support unit and the central column 3 are connected to the seabed by a mooring chain 11. The five mooring chains 11 are arranged in a central symmetrical manner.

[0038] More specifically, each floating support unit includes a cylindrical foundation 4, a side column 5, an air-lift swing plate 6 and a U-shaped water tank 9. The cylindrical foundation 4 is fixedly connected to the central column 3 through a cross brace 8 and a roll-stabilizing rudder is provided on the outer side of the cylindrical foundation 4. The bottom of the cylindrical foundation 4 is fixedly connected to the air-lift swing plate 6. The air-lift swing plate 6 has a suppressing effect on the heave movement of the wind turbine. The upper end of the cylindrical foundation 4 is fixedly connected to the side column 5. The side column 5 is built with a U-shaped water tank 9 with liquid to alleviate the roll and pitch of the floating wind turbine when the pitch angle of the floating wind turbine does not exceed the expected pitch angle. The side columns 5 in adjacent floating support units are fixedly connected by wave-breaking plates 7. The cylindrical foundation 4 and the central column 3 are connected to the mooring chain 11 through the cable guide holes 12 arranged on the side walls.

[0039] like Figure 2 As shown, the U-shaped water tank 9 includes an upper cavity and a lower cavity, which are sealed and fixedly connected to form a cavity inside. The cavity is mainly composed of high-position cavities on both sides and a low-position cavity located between the high-position cavities on both sides. The high-position cavities on both sides and the low-position cavity in the middle are interconnected to form a cavity together. The cavity is pre-filled with liquid, and the liquid height exceeds the height of the low-position cavity, but the liquid does not fill the cavity.

[0040] When waves impact the floating wind turbine, the floating wind turbine will produce pitch and roll. During roll, the liquid in the U-shaped water tank 9 will sway left and right, and the oscillation period is equal to the floating wind turbine's shaking motion period, resulting in harmonic roll. When no other external force is applied to the U-shaped water tank 9, the oscillation phase of the liquid in the U-shaped water tank 9 lags behind the floating wind turbine's roll by 1 / 4 period. Under this condition, the liquid in the U-shaped water tank 9 generates a righting moment that is equal in magnitude and opposite in direction to the floating wind turbine's roll moment, reducing the floating wind turbine's roll motion and achieving roll reduction of the floating wind turbine. The same applies to the floating wind turbine's pitch roll.

[0041] More specifically, the working principle diagram of the U-shaped water tank 9 is as follows: Figure 3 As shown in Figure 2, when the floating wind turbine reaches the maximum left roll angle, Figure 3 As shown in Figure a, the left tank position reaches the lowest, the liquid levels in the left and right tanks are equal, and the liquid in the right tank begins to flow to the left tank at the maximum flow rate. At the same time, the floating fan begins to right itself toward the equilibrium position due to the action of the righting torque. When the floating fan reaches the equilibrium position, as shown in Figure b, the left and right tanks are on the same horizontal line, and the floating fan will roll toward the right tank at the maximum speed. At this time, the liquid level in the left tank reaches the highest, and due to the gravity of the liquid, a maximum righting torque is generated in the U-shaped tank to offset the rolling motion of the floating fan toward the right tank. When it reaches the equilibrium position, as shown in Figure b, the left and right tanks are on the same horizontal line, and the floating fan will roll toward the right tank at the maximum speed. Figure 3When the floating fan reaches the position shown in Figure c, the floating fan reaches the maximum right roll angle, and the liquid level height is equal. The U-shaped water tank 9 does not generate torque, and the liquid in the U-shaped water tank 9 will flow to the right tank at the maximum speed. At the same time, the floating fan begins to right itself to the equilibrium position under the action of the righting torque. When the floating fan reaches the state shown in Figure d, the left and right tanks are on the same horizontal line, and the floating fan will roll toward the left tank at the maximum roll angular velocity. At this time, the liquid level height of the right tank reaches the maximum value, and the liquid in the U-shaped water tank 9 generates the maximum righting torque to offset the roll motion to the left tank.

[0042] Specifically, the anti-roll rudder includes a rudder wing 10, a servo motor, a hydraulic mechanism and a control system. The control system is electrically connected to the servo motor and the hydraulic mechanism respectively. The hydraulic mechanism includes a hydraulic cylinder and a transmission mechanism. The hydraulic cylinder is connected to the servo motor through the transmission mechanism. The output end of the servo motor is connected to the rudder wing 10 through the rotating shaft of the transmission mechanism.

[0043] More specifically, the control system includes a pitch controller, a roll controller and a sensor. The pitch controller is used to control the rudder 10 to reduce the pitch of the floating wind turbine; the roll controller is used to control the rudder 10 to reduce the roll of the floating wind turbine; the sensor is used to monitor the motion state of the floating wind turbine in real time, including the motion amplitude, speed, acceleration, and motion period; the swing angle, angular velocity, and angular acceleration of the rudder; the wave height and period of the water surface, and the wind speed on the water surface.

[0044] like Figure 4 and Figure 5As shown, the wave-breaking plate 7 is mainly composed of two fence plates 13 arranged opposite to each other and a wave-breaking column 14 between the two fence plates 13. The two fence plates 13 are arranged parallel to the sea level. A plurality of wave-breaking columns 14 are evenly arranged in an array between the two fence plates 13. The wave-breaking columns 14 are perpendicular to the two fence plates 13 and are arranged integrally with the two fence plates 13. The side columns (5) in adjacent floating support units are fixedly connected by the fence plates (13) and the wave-breaking columns (14). The contact portion of the fence plates (13) with the side columns (5) and the wave-breaking columns (14) close to the side columns (5) are connected to the side columns (5) by welding. The width of the wave-breaking column 14 is smaller than the width of a single fence of the fence plates 13. The structure of the wave-breaking plate 7 can achieve an energy dissipation effect through deformation and reflection of wave propagation. The upper end of the wave-breaking plate 7 is on the free water surface, and the middle and lower ends have a certain diving depth in the water. The gap arrangement of the fence plates 13 effectively reduces the buoyancy of the waves. The multiple wave-breaking columns 14 further reduce the stress area of ​​the structure. The wave-breaking board 7 is a hollow structure, which can effectively reduce the stress area of ​​the structure and cause waves to collide inside the structure, thereby dissipating energy and contributing to the stability of the structure. The wave-breaking board is composed of wave-breaking columns 14 and fence plates 13 with gaps. This design can dissipate the energy of the incident wave in front of the board, deform the wave or even break it, and prevent it from further propagating. At the same time, the turbulence between the water entering the structure and the water transmitted to the breakwater intensifies, forming vortices, thereby promoting the dissipation of wave energy. In addition, multiple wave-breaking columns 14 are evenly distributed in the array, and when waves are incident, the structure can reflect part of the wave energy in front of the board. The wave-breaking columns 14 and the fence plates 13 with gaps in the wave-breaking board 7 overlap with each other, so that the wave-breaking board 7 has multiple wave-breaking chambers. When the wave passes through the fence plates 13, part of the wave energy is dissipated, and the water entering the structure is reflected multiple times by the wave-breaking chambers and dissipates energy, which reduces the stress on the structure, is beneficial to the safety and stability of the wave-breaking board 7, and optimizes the wave-breaking effect.

[0045] Specifically, four U-shaped water tanks 9 are placed in a centrally symmetrical manner to offset the additional moment.

[0046] A method for controlling a floating wind turbine, the method comprising the following steps:

[0047] Step 1: The floating wind turbine is affected by wind and waves at sea. Under the action of wind, the wind turbine unit 1 of the floating wind turbine converts mechanical energy into electrical energy to generate electricity in real time and supplies electricity to the anti-roll rudder;

[0048] Step 2: The sensor on the anti-roll rudder monitors the pitch angle of the floating wind turbine in real time and transmits the pitch angle to the control system of each anti-roll rudder;

[0049] Step 3: The control system controls each rudder blade 10 of the floating wind turbine in real time according to the pitch angle monitored by the sensor in real time and the preset desired pitch angle, so as to realize continuous control of the wave energy device.

[0050] Step 3 is as follows: Figure 6 As shown, the control system receives the sensor data for real-time calculation and analysis. When the control system determines that the pitch angle of the floating wind turbine does not exceed the expected pitch angle, the floating wind turbine does not start the anti-roll rudder, and the automatic anti-roll mode is enabled. The U-shaped water tank 9, the air heave plate 6, and the wave-breaking plate 7 are used for passive anti-roll, and the floating wind turbine continues to monitor whether the pitch angle exceeds the expected pitch angle and make a judgment.

[0051] When the control system determines that the pitch angle of the floating wind turbine exceeds the expected pitch angle, the floating wind turbine activates the anti-roll rudder. The pitch angle is divided into two parts: the pitch angle and the roll angle. The anti-roll rudder determines whether the pitch angle and the roll angle are within the expected pitch angle through the control system. If they are within the expected pitch angle, the pitch controller and the roll controller are controlled to shut down respectively.

[0052] If it exceeds the expected pitch angle, the pitch controller / roll controller deploys the rudder wing 10 through the hydraulic mechanism, and then controls the rudder wing 10 through the servo motor to pitch / roll reduce the floating wind turbine, and then continues to judge whether the floating wind turbine is within the expected pitch angle.

Claims

1. A floating wind turbine with anti-sway function, characterized in that: The invention comprises a wind turbine set (1), a tower (2), a floating platform, a roll stabilizer and a plurality of mooring chains (11), wherein the wind turbine set (1) is mounted on the top of the tower (2), the bottom of the tower (2) is mounted on the floating platform, a plurality of roll stabilizers are arranged on the outer side of the floating platform, and the floating platform floats on the sea surface and is connected to the seabed via a plurality of mooring chains (11).

2. A floating wind turbine with anti-sway function according to claim 1, characterized in that: The floating platform comprises a central column (3), a floating support unit, a wave-breaking plate (7) and a cross brace (8); the bottom end of the tower (2) is mounted on the central column (3); the central column (3) is located at the center of a square formed by four floating support units; adjacent floating support units are fixedly connected via the wave-breaking plate (7); the four floating support units are fixedly connected to the central column (3) via the cross brace (8); a roll stabilizer is provided on the outer side of each floating support unit; and each floating support unit and the central column (3) are connected to the seabed via a mooring chain (11).

3. The floating wind turbine with anti-sway function according to claim 2, characterized in that: Each floating support unit comprises a cylindrical foundation (4), a side column (5), an air-heaving swing plate (6) and a U-shaped water tank (9); the cylindrical foundation (4) is fixedly connected to the central column (3) via a cross brace (8) and a roll-stabilizing rudder is provided on the outer side of the cylindrical foundation (4); the bottom of the cylindrical foundation (4) is fixedly connected to the air-heaving swing plate (6); the upper end of the cylindrical foundation (4) is fixedly connected to the side column (5); the side column (5) is built with a U-shaped water tank (9); the side columns (5) in adjacent floating support units are fixedly connected via a wave-breaking plate (7); and the cylindrical foundation (4) and the central column (3) are connected to a mooring chain (11) via a fairlead hole (12) provided on the side wall.

4. The floating wind turbine with anti-sway function according to claim 1, characterized in that: The U-shaped water tank (9) comprises an upper cavity and a lower cavity, the upper cavity and the lower cavity are sealed and fixedly connected and enclose a cavity inside, the cavity is mainly composed of high-position cavities on both sides and a low-position cavity located between the high-position cavities on both sides, and the high-position cavities on both sides and the low-position cavity in the middle are interconnected to form a cavity together.

5. The floating wind turbine with anti-sway function according to claim 1, characterized in that: The anti-roll rudder comprises a rudder wing (10), a servo motor, a hydraulic mechanism and a control system, wherein the control system is electrically connected to the servo motor and the hydraulic mechanism respectively, the hydraulic mechanism comprises a hydraulic cylinder and a transmission mechanism, the hydraulic cylinder is connected to the servo motor via the transmission mechanism, and the servo motor is connected to the rudder wing (10).

6. The floating wind turbine with anti-sway function according to claim 5, characterized in that: The control system comprises a pitch controller, a roll controller and a sensor. The pitch controller is used to control the rudder (10) to reduce the pitch of the floating wind turbine; the roll controller is used to control the rudder (10) to reduce the roll of the floating wind turbine; and the sensor is used to monitor the movement state of the floating wind turbine in real time.

7. The floating wind turbine with anti-sway function according to claim 2, characterized in that: The wave-breaking plate (7) is mainly composed of two fence plates (13) arranged opposite to each other and a wave-breaking column (14) between the two fence plates (13). The two fence plates (13) are arranged parallel to the sea level. A plurality of wave-breaking columns (14) are evenly distributed in an array between the two fence plates (13). The wave-breaking columns (14) are perpendicular to the two fence plates (13) and are arranged integrally with the two fence plates (13). The side columns (5) in adjacent floating support units are fixedly connected through the fence plates (13) and the wave-breaking columns (14).

8. The floating wind turbine with anti-sway function according to claim 1, characterized in that: The four U-shaped water tanks (9) are placed in a centrally symmetrical manner.

9. The control method of a floating wind turbine according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: Step 1: The floating wind turbine is subjected to the action of wind and waves at sea. Under the action of wind, the wind turbine unit (1) of the floating wind turbine converts mechanical energy into electrical energy to generate electricity in real time, and supplies electricity to the anti-roll rudder; Step 2: The sensors on the anti-roll rudder monitor the pitch angle of the floating wind turbine in real time. The pitch angle is divided into two parts: pitch angle and roll angle. The pitch angle is transmitted to the control system of each anti-roll rudder; Step 3: The control system controls each rudder blade (10) of the floating wind turbine in real time according to the pitch angle monitored in real time by the sensor and the preset desired pitch angle, so as to realize continuous control of the wave energy device.

10. A method for controlling a floating wind turbine according to claim 9, characterized in that: The step 3 is as follows: When the control system determines that the pitch angle of the floating wind turbine does not exceed the expected pitch angle, the floating wind turbine does not start the anti-roll rudder, relies on the U-shaped water tank (9), the air heave plate (6), and the wave plate (7) to passively reduce the roll, and continuously monitors whether the pitch angle of the floating wind turbine exceeds the expected pitch angle and makes a judgment; When the control system determines that the pitch angle of the floating wind turbine exceeds the expected pitch angle, the floating wind turbine activates the anti-roll rudder, which determines through the control system whether the pitch angle and roll angle are within the expected pitch angle. If they are within the expected pitch angle, the pitch controller and roll controller are controlled to shut down respectively. If the expected pitch angle is exceeded, the pitch controller / roll controller deploys the rudder wing (10) through a hydraulic mechanism, and then controls the rudder wing (10) through a servo motor to reduce the pitch / roll of the floating wind turbine, and then continues to judge whether the floating wind turbine is within the expected pitch angle.

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