Floating eagle-type wave power generation device adopting hybrid power for positioning and control method of floating eagle-type wave power generation device

Abstract

The invention discloses a floating eagle type wave power generation device adopting hybrid power positioning and a control method, and belongs to the technical field of renewable energy utilization. The device comprises a main body, a turret-type single-point mooring system and an auxiliary power positioning system, wherein the main body comprises a semi-submersible platform, an eagle-type wave-absorbing floater connected with the platform through a hinge and an energy conversion system; the mooring system is arranged on a platform bow, and the auxiliary system comprises a propeller at the bottom of a platform stern stand column. According to the control method, the target heading is determined through the sensor collecting position, heading and wave direction, the mooring system is preliminarily positioned by means of the weather vane effect, the auxiliary system is controlled through a low-frequency motion model, an LQR controller, thrust distribution optimization and double-loop PID, the heading is accurately adjusted, drifting is restrained, and low-power-consumption operation is conducted when deviation is small.

Description

Technical Field

[0001] This invention relates to the field of renewable energy utilization technology, specifically to a floating eagle-shaped wave energy power generation device and control method that adopts hybrid power positioning. Background Technology

[0002] The floating eagle wave energy generator is a typical oscillating wave energy absorption device. Its working principle is as follows: the eagle wave-absorbing float will generate pitch motion relative to the main body of the semi-submersible platform under the action of waves. This pitch motion can drive the energy conversion system at the back end of the device to operate, thereby realizing the power generation function.

[0003] To ensure excellent wave-resistance, two main methods exist in existing technologies. The first method employs a single-point mooring positioning system. This system connects the device to a mooring chain via a rotatable turret, the other end of which is connected to an anchoring foundation on the seabed. Under environmental loads such as wind, waves, and currents, the device automatically rotates around a single point like a weather vane, passively aligning itself with the dominant load direction. However, under the combined effects of wind, waves, and currents, the device's rotational equilibrium angle will be in the direction of the combined force of these forces. This direction is not always precisely aligned with the wave direction and may also exhibit a fishtail effect to some extent. Furthermore, in real marine environments, wave direction changes rapidly and exhibits dispersion, i.e., short-peak waves. Turret-type mooring systems rely on enormous environmental torques to adjust their attitude, resulting in a very slow attitude adjustment response and significant inertia.

[0004] The second method employs a fully dynamic positioning system. This system eliminates the need for mooring chains, instead using multiple computer-controlled propellers mounted at the bottom of the device for positioning and orientation. These propellers actively apply thrust to resist environmental loads such as wind, waves, and currents, enabling the device to achieve high-precision positioning and orientation. However, the fully dynamic positioning system has significant drawbacks: it requires continuous propeller operation to withstand all environmental loads, especially in harsh sea conditions. The energy consumed during dynamic positioning can become enormous, potentially exceeding the device's own power generation capacity, ultimately resulting in a negative net output. From an economic perspective, this is not feasible. Summary of the Invention

[0005] The purpose of this invention is to provide a floating eagle wave energy power generation device and control method that adopts hybrid power positioning, in order to solve the problem that the pure single-point mooring system in existing floating eagle wave energy power generation devices is difficult to quickly and accurately align with the real-time changing wave direction, resulting in low energy capture efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] In a first aspect, the present invention provides a floating eagle-type wave energy power generation device employing hybrid power positioning, comprising: a main body of the floating eagle-type wave energy power generation device, a turret-type single-point mooring system, an auxiliary dynamic positioning system, and a controller; wherein...

[0008] The turret-type single-point mooring system is located at the bow of the main body of the floating eagle-type wave energy generator;

[0009] The auxiliary power positioning system is installed at the stern of the main body of the floating eagle wave energy generator and is used to provide auxiliary thrust or torque to the main body of the floating eagle wave energy generator.

[0010] The controller is connected to the main body of the floating eagle-type wave energy generator, the turret-type single-point mooring system, and the auxiliary dynamic positioning system, respectively, and is used to receive feedback signals from each part and send control commands.

[0011] In one possible implementation, the floating eagle wave energy generator mainly includes a semi-submersible platform, an eagle-shaped wave-absorbing buoy, and an energy conversion system; the eagle-shaped wave-absorbing buoy is connected to the semi-submersible platform by a hinge and can perform pitching motion relative to the semi-submersible platform; the energy conversion system is located on the semi-submersible platform and is connected to the eagle-shaped wave-absorbing buoy for converting the pitching motion of the eagle-shaped wave-absorbing buoy into electrical energy.

[0012] In one possible implementation, the turret-type single-point mooring system includes a turret, a turret sleeve, an upper main bearing, a lower bearing, a mooring chain, and an anchoring foundation; the turret is located outside the semi-submersible platform, and the turret sleeve is installed on the semi-submersible platform and docked with the turret; the turret and the turret sleeve are connected by the upper main bearing and the lower bearing; one end of the mooring chain is fixed to the bottom of the turret, and the other end is fixedly connected to the anchoring foundation located on the seabed.

[0013] In one possible implementation, the auxiliary dynamic positioning system includes thrusters; the stern of the semi-submersible platform is provided with columns, and the thrusters are respectively installed at the bottom of the columns; the thrusters are omnidirectional thrusters or tunnel thrusters, and the thrusters are signal-connected to the controller to receive thrust control commands sent by the controller.

[0014] Secondly, the present invention provides a control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning, applicable to the aforementioned device, comprising the following steps:

[0015] The actual position and heading of the device are obtained by sensors, and the main direction of wave propagation is obtained by analyzing the current sea conditions using wave testing instruments. The main direction of wave propagation is then used as the target heading.

[0016] The device uses a turret-type single-point mooring system to apply a rotational torque to the device using the environmental forces generated by wind, waves and currents, causing the device to rotate around the turret and obtain the device's attitude after preliminary adjustment.

[0017] Based on the initially adjusted device attitude and the actual position, a low-frequency motion model describing the influence of the thruster's thrust on the device's low-frequency motion is established.

[0018] Based on the low-frequency motion model, the actual heading, and the target heading, a linear quadratic regulator controller is established, the cost function is determined, and the optimal control input is obtained by solving the problem.

[0019] Based on the optimal control input, the thrust distribution optimization algorithm is run to obtain the thrust command for each thruster with the goal of minimizing total power consumption, while meeting the requirements of total force and total torque.

[0020] The device's real-time yaw angle is obtained using inertial sensors and a compass. The deviation between the real-time yaw angle and the target heading is compared. Energy capture optimization is performed based on the deviation. The thrusters are controlled to output thrust according to the thrust command, and the device's attitude is updated.

[0021] The device continuously senses the real-time status and current sea state through sensors, and adjusts the low-frequency motion model, the optimal control input, and the thrust command based on the real-time status and current sea state to achieve hybrid power positioning of the device.

[0022] In one possible implementation, a low-frequency motion model describing the low-frequency motion of the thrust-affected device is established, including:

[0023] Based on the preliminarily adjusted device attitude and the actual position, the research object of the device's low-frequency motion is determined to be three degrees of freedom in the horizontal plane: sway, roll, and pitch. A low-frequency motion equation is constructed, including a low-frequency mass inertia matrix, a low-frequency damping matrix, a low-frequency velocity vector, and thruster control force and torque vectors. The low-frequency motion equation is as follows:

[0024]

[0025] In the formula: ν=[u LF ,v LF ,r LF ] is the low-frequency velocity vector of the device; M L It is the system's low-frequency mass-inertia matrix, including the floating body mass and added mass; D L It is the low-frequency damping matrix of the system, including hydrodynamic damping and the equivalent damping of the mooring system; τ t =[F X ,FY ,τ Z ] T The control force and torque vector provided by the dynamic positioning thruster system.

[0026] In one possible implementation, a linear quadratic regulator controller is established, the cost function is determined, and the optimal control input is obtained by solving for it. Obtaining the optimal control input includes:

[0027] Substituting the state vector of the device and the control input of the thruster into the cost function, the cost function is the sum of the integral of the product of the state vector and the state weight matrix and the integral of the product of the control input and the control weight matrix. The optimal control input is obtained by minimizing the cost function. The state weight matrix reflects the degree of importance attached to heading error and slow drift, while the control weight matrix reflects the degree of importance attached to thruster energy consumption.

[0028]

[0029] In the formula: x T Qx represents the weights on the state vector; u T Ru represents the weight of controlling energy consumption; the Q matrix, with weight values ​​reflecting the importance attached to heading error and slow drift; the R matrix, with weight values ​​reflecting the importance attached to energy consumption.

[0030] In one possible implementation, a thrust allocation optimization algorithm is run to obtain thrust commands for each thruster, aiming to minimize total power consumption while meeting the total force and total torque requirements. These commands include:

[0031] Based on the optimal control input, the total force and total torque required by the device are determined. The thrust distribution optimization algorithm is run to meet the total force and total torque requirements while considering the thrust limit and thrust change rate limit of each thruster. With the goal of minimizing the total power consumption of the thrusters, the thrust magnitude and direction of each thruster are calculated, and the thrust command of each thruster is obtained.

[0032] In one possible implementation, energy capture optimization is performed based on the deviation, the thrusters are controlled to output thrust according to the thrust command, and the device attitude is updated, including:

[0033] When the deviation between the real-time yaw angle and the target heading is within a preset range, the control auxiliary dynamic positioning system enters a low-power standby state, only outputting thrust to offset the drift of the device; when the deviation exceeds the preset range, the real-time yaw angle is compared with the target heading at a preset frequency, and dual-loop PID control is adopted. The outer PID judges the yaw deviation window, and the inner PID calculates the magnitude and direction of the thrust, controlling the thruster to output pulsed short thrust to adjust the attitude of the device and update the attitude of the device to meet the wave requirements.

[0034] Compared with the prior art, the advantages of this invention are as follows:

[0035] ① Compared to a fully dynamic positioning system, the dynamic positioning system of the present invention only functions as an auxiliary component and does not bear the main wind, wave and current loads. Its energy consumption is only 10% to 20% or less of that of a fully dynamic positioning system, thereby reducing the overall positioning energy consumption of the device and avoiding the problem of excessive energy consumption caused by the continuous operation of the thruster to resist all environmental loads in harsh sea conditions.

[0036] ② Compared to purely passive single-point mooring systems, this invention, by utilizing the active heading control function of the auxiliary dynamic positioning system, can respond quickly and accurately to changes in wave direction. This overcomes the limitations of purely passive single-point mooring systems, which rely on huge environmental torques to adjust attitude, have slow response, and large inertia. It also avoids the problem that the device cannot be aligned with the dominant wave direction in time due to rapid changes in wave direction, ensuring that the device is in the optimal wave-catching state most of the time. This allows the eagle-type wave-absorbing buoy to always face the direction of the incoming wave, maintain a stable effective wave-facing area, and directly improve the energy capture capability of the wave energy-capturing structure.

[0037] ③ The present invention actively suppresses the slow drift motion of the device through the auxiliary dynamic positioning system, which can effectively reduce the range of motion of the device in the horizontal plane, avoid the mooring chain from bearing excessive tension due to large drift of the device, thereby reducing the peak impact load on the mooring chain during operation and reducing the accumulation of fatigue damage to the mooring chain.

[0038] ④ During the long-term operation of the device, the main displacement and orientation changes are handled by the relatively simple and extremely reliable passive turret single-point mooring system, so that the auxiliary dynamic positioning system does not need to operate at high power, but only needs to maintain a low power state to meet the control requirements. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a shipboard view of the floating eagle-shaped wave energy generation device in an embodiment of the present invention.

[0041] Figure 2 This is a stern view of the floating eagle-shaped wave energy generation device in an embodiment of the present invention.

[0042] Figure 3 This is a waterline view of the floating eagle-shaped wave energy power generation device in an embodiment of the present invention.

[0043] 1. Buoys of a semi-submersible platform; 2. Stern pillars of a semi-submersible platform; 3. Bow pillars of a semi-submersible platform; 4. Upper deck of a semi-submersible platform; 5. Eagle-type wave-absorbing buoys; 6. Energy conversion system; 7. Turret-type single-point mooring system; 8. Mooring chain; 9. Propulsion unit. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0045] Example:

[0046] It should be noted that the terms "comprising" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such processes, methods, products, or devices.

[0047] This invention provides a floating eagle-type wave energy generator employing hybrid power positioning, comprising: a main body of the floating eagle-type wave energy generator, a turret-type single-point mooring system, an auxiliary dynamic positioning system, and a controller; wherein...

[0048] The turret-type single-point mooring system is located at the bow of the main body of the floating eagle-type wave energy generator;

[0049] The auxiliary power positioning system is installed at the stern of the main body of the floating eagle wave energy generator and is used to provide auxiliary thrust or torque to the main body of the floating eagle wave energy generator.

[0050] The controller is connected to the main body of the floating eagle-type wave energy generator, the turret-type single-point mooring system, and the auxiliary dynamic positioning system, respectively, and is used to receive feedback signals from each part and send control commands.

[0051] In some embodiments, the main body of the floating eagle wave energy generation device includes a semi-submersible platform, an eagle wave-absorbing buoy, and an energy conversion system; the eagle wave-absorbing buoy is connected to the semi-submersible platform by a hinge and can perform pitching motion relative to the semi-submersible platform; the energy conversion system is disposed on the semi-submersible platform and is drivenly connected to the eagle wave-absorbing buoy, and is used to convert the pitching motion of the eagle wave-absorbing buoy into electrical energy.

[0052] In some embodiments, the turret-type single-point mooring system includes a turret, a turret sleeve, an upper main bearing, a lower bearing, a mooring chain, and an anchoring foundation; the turret is located outside the semi-submersible platform, and the turret sleeve is installed on the semi-submersible platform and docked with the turret; the turret and the turret sleeve are connected by the upper main bearing and the lower bearing; one end of the mooring chain is fixed to the bottom of the turret, and the other end is fixedly connected to the anchoring foundation located on the seabed.

[0053] In some embodiments, the auxiliary dynamic positioning system includes thrusters; the stern of the semi-submersible platform is provided with columns, and the thrusters are respectively installed at the bottom of the columns; the thrusters are omnidirectional thrusters or tunnel thrusters, and the thrusters are signal-connected to the controller to receive thrust control commands sent by the controller.

[0054] In some embodiments, the device further includes a GPS, a gyroscope, a wave testing instrument, and an inertial sensor; the GPS and gyroscope are both signal-connected to the controller, sending the actual position and heading data of the device to the controller; the wave testing instrument is signal-connected to the controller, sending wave propagation direction data to the controller; and the inertial sensor is signal-connected to the controller, sending yaw angle data of the device to the controller.

[0055] In some embodiments, the controller includes an LQR controller based on a low-frequency motion model; the LQR controller is connected to the GPS, gyroscope, and wave testing instrument signals, receives the actual position, actual heading, and wave propagation direction data, and is used to process the multiple-input multiple-output system and achieve a balance between state conditioning and control costs.

[0056] In some embodiments, the controller further includes a thrust allocation optimization module; the thrust allocation optimization module is signal-connected to the LQR controller and the thrusters, receives total force or torque data output by the LQR controller, sends thrust allocation instructions to the thrusters, and allocates the thrust magnitude and direction of each thruster under the premise of meeting the total force or torque requirements.

[0057] In some embodiments, the controller further includes a dual-loop PID controller; the outer PID of the dual-loop PID controller is connected to the inertial sensor signal, receives yaw angle data and determines the yaw window; the inner PID of the dual-loop PID controller is connected to the thruster signal, calculates the thrust magnitude and direction based on the yaw window data and sends it to the thruster.

[0058] In some embodiments, the semi-submersible platform further includes buoys, bow columns, and an upper deck; the buoys, bow columns, and stern columns are all fixedly connected to the upper deck, together forming the support structure of the semi-submersible platform; the eagle-type wave-absorbing buoys and energy conversion system are all located at corresponding positions on the upper deck.

[0059] In some embodiments, there are multiple mooring chains; the multiple mooring chains are evenly distributed circumferentially along the bottom of the turret, and the two ends of each mooring chain are fixedly connected to the bottom of the turret and the anchoring foundation, respectively, to provide positioning tension for the semi-submersible platform.

[0060] The present invention also provides a control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning, applicable to the aforementioned device, comprising the following steps:

[0061] The actual position and heading of the device are obtained by sensors, and the main direction of wave propagation is obtained by analyzing the current sea conditions using wave testing instruments. The main direction of wave propagation is then used as the target heading.

[0062] The device uses a turret-type single-point mooring system to apply a rotational torque to the device using the environmental forces generated by wind, waves and currents, causing the device to rotate around the turret and obtain the device's attitude after preliminary adjustment.

[0063] Based on the initially adjusted device attitude and the actual position, a low-frequency motion model describing the influence of the thruster's thrust on the device's low-frequency motion is established.

[0064] Based on the low-frequency motion model, the actual heading, and the target heading, a linear quadratic regulator controller is established, the cost function is determined, and the optimal control input is obtained by solving the problem.

[0065] Based on the optimal control input, the thrust distribution optimization algorithm is run to obtain the thrust command for each thruster with the goal of minimizing total power consumption, while meeting the requirements of total force and total torque.

[0066] The device's real-time yaw angle is obtained using inertial sensors and a compass. The deviation between the real-time yaw angle and the target heading is compared. Energy capture optimization is performed based on the deviation. The thrusters are controlled to output thrust according to the thrust command, and the device's attitude is updated.

[0067] The device continuously senses the real-time status and current sea state through sensors, and adjusts the low-frequency motion model, the optimal control input, and the thrust command based on the real-time status and current sea state to achieve hybrid power positioning of the device.

[0068] In some embodiments, a low-frequency motion model describing the low-frequency motion of the thrust-affected device is established, including:

[0069] Based on the preliminarily adjusted device attitude and the actual position, the research object of the device's low-frequency motion is determined to be three degrees of freedom in the horizontal plane: sway, roll, and pitch. A low-frequency motion equation is constructed, including a low-frequency mass inertia matrix, a low-frequency damping matrix, a low-frequency velocity vector, and thruster control force and torque vectors. The low-frequency motion equation is as follows:

[0070]

[0071] Where: ν=[u LF ,v LF ,r LF ] is the low-frequency velocity vector of the device; M L It is the system's low-frequency mass-inertia matrix, including the floating body mass and added mass; D L It is the low-frequency damping matrix of the system, including hydrodynamic damping and the equivalent damping of the mooring system; τ t =[F X ,F Y ,τ Z ] T The control force and torque vector provided by the dynamic positioning thruster system.

[0072] In some embodiments, a linear quadratic regulator controller is established, a cost function is determined, and the optimal control input is obtained by solving for it. Obtaining the optimal control input includes:

[0073] Substituting the state vector of the device and the control input of the thruster into the cost function, the cost function is the sum of the integral of the product of the state vector and the state weight matrix and the integral of the product of the control input and the control weight matrix. The optimal control input is obtained by minimizing the cost function. The state weight matrix reflects the degree of importance attached to heading error and slow drift, while the control weight matrix reflects the degree of importance attached to thruster energy consumption.

[0074]

[0075] x T Qx represents the weights on the state vector; u T Ru represents the weight of controlling energy consumption; the Q matrix, with weight values ​​reflecting the importance attached to heading error and slow drift; the R matrix, with weight values ​​reflecting the importance attached to energy consumption.

[0076] In some embodiments, a thrust allocation optimization algorithm is run to obtain thrust commands for each thruster, aiming to minimize total power consumption while meeting total force and total torque requirements. This includes:

[0077] Based on the optimal control input, the total force and total torque required by the device are determined. The thrust distribution optimization algorithm is run to meet the total force and total torque requirements while considering the thrust limit and thrust change rate limit of each thruster. With the goal of minimizing the total power consumption of the thrusters, the thrust magnitude and direction of each thruster are calculated, and the thrust command of each thruster is obtained.

[0078] In some embodiments, energy capture optimization is performed based on the deviation, controlling the thrusters to output thrust according to the thrust command, and updating the device attitude, including:

[0079] When the deviation between the real-time yaw angle and the target heading is within a preset range, the control auxiliary dynamic positioning system enters a low-power standby state, only outputting thrust to offset the drift of the device; when the deviation exceeds the preset range, the real-time yaw angle is compared with the target heading at a preset frequency, and dual-loop PID control is adopted. The outer PID judges the yaw deviation window, and the inner PID calculates the magnitude and direction of the thrust, controlling the thruster to output pulsed short thrust to adjust the attitude of the device and update the attitude of the device to meet the wave requirements.

[0080] As a preferred example, the present invention provides a floating eagle-shaped wave energy power generation device employing hybrid power positioning. The floating eagle-shaped wave energy power generation device mainly consists of the following three parts:

[0081] The main body of the floating eagle wave energy power generation device includes a semi-submersible platform as a base, a wave energy capture structure—the eagle wave-absorbing float—connected to the semi-submersible platform by hinges and capable of pitching relative to the semi-submersible platform, and an energy conversion system.

[0082] Turret-type single-point mooring system: This system is located at the bow of a semi-submersible platform. The turret is situated on the exterior of the platform, with multiple mooring chains anchored to its base. A turret sleeve is installed on the platform and connects to the turret. The turret and sleeve are connected via upper and lower bearings. Anchoring foundations are located on the seabed to secure the seabed ends of the mooring chains. The system's function is to withstand most environmental loads from wind, waves, and currents, providing basic positioning for the equipment and allowing it to rotate freely around the single-point turret under the influence of a weathervane effect.

[0083] Assisted Dynamic Positioning System: Two omnidirectional thrusters or tunnel thrusters are installed at the bottom of the two pillars at the stern of the semi-submersible platform. A turret-type single-point mooring system resists most environmental forces. Once the platform has rotated to a certain approximate position, the assisted dynamic positioning system provides a small but precise auxiliary thrust / torque for accurate heading control and suppression of slow drift, improving the wave-absorbing buoy's wave-absorbing capability and increasing power generation efficiency.

[0084] This invention provides a control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning. The control flow of the floating eagle-shaped wave energy power generation device with hybrid power positioning is as follows:

[0085] (1) State perception and target determination

[0086] The controller uses GPS and a gyroscope to obtain the device's actual position (x, y) and actual heading ψ in real time. actual The controller analyzes data from wave testing instruments to identify the main direction of wave propagation under the current sea conditions in real time. This direction is the ideal wave-facing direction of the device, which is the target heading ψ. desired =α wave .

[0087] (2) The device is positioned by a turret-type single-point mooring system.

[0088] A turret is a precisely designed, rotatable mechanical structure. Its lower part is connected to multiple mooring chains, while large bearings allow the main body of the device to rotate freely 360°. When the direction of wind, waves, or current changes, the environmental forces acting on the main body of the device, such as wind, waves, and current, will generate a rotational torque (the point of application of the resultant force usually does not coincide with the rotation center of the turret). The device will then begin to rotate around the turret until its attitude is adjusted to a state where the environmental forces such as wind, waves, and current are minimized. The long axis of the device will then tend to align with the direction of the dominant environmental forces, i.e., the weathervane effect.

[0089] (3) Assisted dynamic positioning control process

[0090] To achieve precise heading control and efficient slow drift suppression while minimizing energy consumption, this patent utilizes a linear quadratic regulator (LQR) based on a low-frequency motion model as the core control algorithm for dynamic positioning control. The LQR is better suited for multiple-input multiple-output (MIMO) systems and achieves a theoretically optimal balance between state regulation and control costs.

[0091] a. Establishment of low-frequency motion model

[0092] A mathematical model is established to describe the low-frequency motion of the thrust-influenced device of a dynamic positioning system in moored condition, focusing primarily on three degrees of freedom in the horizontal plane: surge, sway, and yaw. Its low-frequency motion equations can be simplified as follows:

[0093]

[0094] in:

[0095] ν=[u LF ,v LF ,r LF [ ] is the low-frequency velocity vector of the device (sway velocity, sway velocity, and pitch angular velocity);

[0096] M L It is the system's low-frequency mass-inertia matrix, including the floating body mass and added mass; D L It is the low-frequency damping matrix of the system, which includes hydrodynamic damping and the equivalent damping of the mooring system;

[0097] τ t =[F X ,F Y ,τ Z ] T The control force and torque vector provided by the dynamic positioning thruster system.

[0098] b. LQR controller design

[0099] The goal of an LQR controller is to find an optimal control input u that minimizes a quadratic cost function J:

[0100]

[0101] x T Qx represents the weights on the state vector;

[0102] u T Ru represents the weight for controlling energy consumption (i.e., thruster thrust);

[0103] The Q matrix, with its weights reflecting the degree of importance placed on heading error and slow drift, indicates that its primary task is accurate wave alignment and minimizing heading error. Low or zero weights represent a reduced focus on heading error and slow drift; in this case, the average position of the device is determined by the turret-type single-point mooring system, while the auxiliary dynamic positioning system operates with low power consumption and does not interfere with the device's position adjustment. This demonstrates the coordinated operation of the auxiliary dynamic positioning system and the turret-type single-point mooring system.

[0104] The R matrix, with its weights, reflects the degree of importance placed on energy consumption. The larger the value of R, the more economical the controller is in calculating thrust, resulting in smoother control commands and lower energy consumption.

[0105] c. Thrust Distribution Optimization

[0106] The total force / torque calculated in the previous step is then rationally allocated to each thruster. A thrust allocation optimization algorithm is run, which, while meeting the total force / torque requirements, aims to minimize total power consumption. The algorithm calculates the magnitude and direction (or rotational speed) of the thrust that each thruster should output, taking into account physical constraints such as the thrust limit and rate of change limit of each thruster.

[0107] d. Energy capture optimization

[0108] According to (1) state perception, the target heading is set. When the deviation between the actual heading of the device and the target heading is within ±5°, the eagle-type wave-absorbing float faces the waves directly, and the wave energy capture is optimal. The inertial sensor (IMU) and compass output yaw angle data in real time, and the dynamic positioning controller compares the target direction at a frequency of 50Hz. When the yaw angle enters the ±5° window, it enters the "low power standby" state, only maintaining a small thrust to offset the small drift. According to the yaw deviation, it provides pulsed short thrust (0.5~2s) as needed, and adjusts quickly instead of continuously outputting to reduce the energy consumption of the auxiliary dynamic positioning system. Dual-loop PID control is adopted. The outer PID judges the yaw window, and the inner PID calculates the thrust magnitude and direction. The reverse torque is generated through the dynamic positioning thruster to suppress slow drift.

[0109] When environmental parameters such as wind, waves, and current change, the position and attitude of the device change significantly. This is detected by the sensors in the next control cycle, and a new round of cyclic adjustment begins.

[0110] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0111] The above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made based on the essence of the content of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A floating eagle-shaped wave energy power generation device employing hybrid power positioning, characterized in that, include: The floating eagle-type wave energy generator consists of its main body, a turret-type single-point mooring system, an auxiliary dynamic positioning system, and a controller; among which... The turret-type single-point mooring system is located at the bow of the main body of the floating eagle-type wave energy generator; The auxiliary power positioning system is installed at the stern of the main body of the floating eagle wave energy generator and is used to provide auxiliary thrust or torque to the main body of the floating eagle wave energy generator. The controller is connected to the main body of the floating eagle-type wave energy generator, the turret-type single-point mooring system, and the auxiliary dynamic positioning system, respectively, and is used to receive feedback signals from each part and send control commands.

2. The floating eagle-shaped wave energy power generation device with hybrid power positioning according to claim 1, characterized in that, The floating eagle wave energy power generation device mainly includes a semi-submersible platform, an eagle wave-absorbing buoy, and an energy conversion system. The eagle wave-absorbing buoy is connected to the semi-submersible platform by a hinge and can perform pitching motion relative to the semi-submersible platform. The energy conversion system is set on the semi-submersible platform and is connected to the eagle wave-absorbing buoy for transmission, and is used to convert the pitching motion of the eagle wave-absorbing buoy into electrical energy.

3. The floating eagle-shaped wave energy power generation device with hybrid power positioning according to claim 1, characterized in that, The turret-type single-point mooring system includes a turret, a turret sleeve, an upper main bearing, a lower bearing, a mooring chain, and an anchoring foundation. The turret is located outside the semi-submersible platform, and the turret sleeve is installed on the semi-submersible platform and docked with the turret. The turret and the turret sleeve are connected by the upper main bearing and the lower bearing. One end of the mooring chain is fixed to the bottom of the turret, and the other end is fixedly connected to the anchoring foundation located on the seabed.

4. The floating eagle-shaped wave energy power generation device with hybrid power positioning according to claim 1, characterized in that, The auxiliary dynamic positioning system includes thrusters; the stern of the semi-submersible platform is provided with columns, and the thrusters are respectively installed at the bottom of the columns; the thrusters are omnidirectional thrusters or tunnel thrusters, and the thrusters are signal-connected to the controller to receive thrust control commands sent by the controller.

5. A control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning, characterized in that, The apparatus applicable to any one of claims 1 to 4 includes the following steps: The actual position and heading of the device are obtained by sensors, and the main direction of wave propagation is obtained by analyzing the current sea conditions using wave testing instruments. The main direction of wave propagation is then used as the target heading. The device uses a turret-type single-point mooring system to apply a rotational torque to the device using the environmental forces generated by wind, waves and currents, causing the device to rotate around the turret and obtain the device's attitude after preliminary adjustment. Based on the initially adjusted device attitude and the actual position, a low-frequency motion model describing the influence of the thruster's thrust on the device's low-frequency motion is established. Based on the low-frequency motion model, the actual heading, and the target heading, a linear quadratic regulator controller is established, the cost function is determined, and the optimal control input is obtained by solving the problem. Based on the optimal control input, the thrust distribution optimization algorithm is run to obtain the thrust command for each thruster with the goal of minimizing total power consumption, while meeting the requirements of total force and total torque. The device's real-time yaw angle is obtained using inertial sensors and a compass. The deviation between the real-time yaw angle and the target heading is compared. Energy capture optimization is performed based on the deviation. The thrusters are controlled to output thrust according to the thrust command, and the device's attitude is updated. The device continuously senses the real-time status and current sea state through sensors, and adjusts the low-frequency motion model, the optimal control input, and the thrust command based on the real-time status and current sea state to achieve hybrid power positioning of the device.

6. The control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning according to claim 5, characterized in that, Establish a low-frequency motion model describing the low-frequency motion of the thrust-affected device, including: Based on the preliminarily adjusted device attitude and the actual position, the research object of the device's low-frequency motion is determined to be three degrees of freedom in the horizontal plane: sway, roll, and pitch. A low-frequency motion equation is constructed, including a low-frequency mass inertia matrix, a low-frequency damping matrix, a low-frequency velocity vector, and thruster control force and torque vectors. The low-frequency motion equation is as follows: In the formula: ν=[u LF ,v LF ,r LF ] is the low-frequency velocity vector of the device; M L It is the system's low-frequency mass-inertia matrix, including the floating body mass and added mass; D L It is the low-frequency damping matrix of the system, including hydrodynamic damping and the equivalent damping of the mooring system; τ t =[F X ,F Y ,τ Z ] T The control force and torque vector provided by the dynamic positioning thruster system.

7. The control method for a floating eagle-shaped wave energy power generation device employing hybrid power positioning according to claim 5, characterized in that, Establish a linear quadratic regulator controller, determine the cost function and solve for the optimal control input, obtaining the optimal control input, including: Substituting the state vector of the device and the control input of the thruster into the cost function, the cost function is the sum of the integral of the product of the state vector and the state weight matrix and the integral of the product of the control input and the control weight matrix. The optimal control input is obtained by minimizing the cost function. The state weight matrix reflects the degree of importance attached to heading error and slow drift, while the control weight matrix reflects the degree of importance attached to thruster energy consumption. In the formula: x T Qx represents the weights on the state vector; u T Ru represents the weight of controlling energy consumption; the Q matrix, with weight values ​​reflecting the importance attached to heading error and slow drift; the R matrix, with weight values ​​reflecting the importance attached to energy consumption.

8. The control method for a floating eagle-shaped wave energy power generation device with hybrid power positioning according to claim 5, characterized in that, The thrust allocation optimization algorithm is run to obtain thrust commands for each thruster, including: (The algorithm aims to minimize total power consumption while meeting total force and torque requirements.) Based on the optimal control input, the total force and total torque required by the device are determined. The thrust distribution optimization algorithm is run to meet the total force and total torque requirements while considering the thrust limit and thrust change rate limit of each thruster. With the goal of minimizing the total power consumption of the thrusters, the thrust magnitude and direction of each thruster are calculated, and the thrust command of each thruster is obtained.

9. The control method for a floating eagle-shaped wave energy power generation device with hybrid power positioning according to claim 5, characterized in that, Based on the aforementioned deviation, energy capture optimization is performed, the thrusters are controlled to output thrust according to the thrust command, and the attitude of the device is updated, including: When the deviation between the real-time yaw angle and the target heading is within a preset range, the control auxiliary dynamic positioning system enters a low-power standby state, only outputting thrust to offset the drift of the device; when the deviation exceeds the preset range, the real-time yaw angle is compared with the target heading at a preset frequency, and dual-loop PID control is adopted. The outer PID judges the yaw deviation window, and the inner PID calculates the magnitude and direction of the thrust, controlling the thruster to output pulsed short thrust to adjust the attitude of the device and update the attitude of the device to meet the wave requirements.

Images