A distributed clutch control method for dual-unit wave energy array

Abstract

The present invention discloses a distributed clutch control method for a dual-unit wave energy array, comprising: numerically modeling the dual-unit wave energy array model and performing hydrodynamic analysis; establishing the time-domain motion equation of the dual-unit wave energy array; establishing the state-space equation of the dual-unit wave energy array, replacing the convolution term of the time-domain motion equation with the state-space equation, and calculating the motion state of the dual-unit wave energy array; and implementing distributed clutch control on the dual-unit wave energy array to maximize the energy extraction from the waves. The present invention significantly improves the overall computational efficiency of the system by coordinating the operation of interconnected distributed controllers. Compared with the traditional single-controller architecture, this method not only optimizes the allocation of computing resources, but also effectively improves the overall energy absorption efficiency of the dual-unit wave energy array, demonstrating higher energy utilization and system response flexibility.

Description

Technical Field

[0001] The present invention belongs to the technical field of wave energy power generation, and in particular relates to a distributed clutch control method for a dual-unit wave energy array. Background Art

[0002] As global energy demand continues to grow, developing clean, renewable energy has become a key strategy for addressing climate change and the energy crisis. Wave energy, in particular, has attracted considerable attention due to its unique advantages. First, wave energy is widely distributed, covering virtually all oceans worldwide, allowing for effective development and utilization in multiple locations. Its high energy density allows it to capture more energy per square meter than wind and solar power, providing greater efficiency for large-scale electricity production. Furthermore, wave energy is highly stable and predictable. Ocean waves operate continuously day and night, with a constant frequency, enabling around-the-clock power generation. This makes it particularly suitable for providing reliable electricity to energy-challenged areas, such as remote islands and offshore oil platforms, thereby reducing reliance on fossil fuels. The versatility and scalability of wave energy technology further enhance its importance in the future energy mix. By complementing other renewable energy sources, such as wind and solar power, wave energy can help improve the efficiency and stability of the overall energy system. Therefore, wave energy is not only a model for clean energy but also has the potential to become a core force in the global energy transition, playing a key role in addressing environmental challenges and promoting sustainable development.

[0003] A mechanical device that converts the kinetic or potential energy of ocean surface waves into electrical energy is called a wave energy converter (WEC). Specifically, the mechanical energy of the waves is captured using a specific energy-capturing mechanism (such as an oscillating body or oscillating water column). This mechanical energy is then converted into pneumatic or hydraulic energy through a power take-off (PTO) system, which in turn drives a generator to generate electricity. Although various types of wave energy converters have been developed, such as differential pressure, overhead, and oscillation, the efficiency of wave energy capture remains low, which is one of the obstacles hindering the large-scale application of wave energy technology.

[0004] Currently, researchers have developed a variety of control strategies, such as reactive power control, locking control, and clutch control, to improve the energy extraction efficiency of wave energy conversion devices. These strategies have been successfully applied to individual wave energy conversion devices and have proven to be an effective method for improving energy absorption efficiency. However, existing control algorithms have not yet been applied to wave energy arrays. This is mainly due to the need to consider the synergistic effects between control algorithms and the complex hydrodynamic interactions between wave energy conversion devices in wave energy arrays. Such interactions may lead to competition for energy extraction between wave energy conversion devices, thereby affecting the overall energy output. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a distributed clutch control method for a dual-unit wave energy array. The delay function of the additional inertial force influence and radiation effect between the wave energy conversion units is introduced into the time domain motion equation to fully consider the complex hydrodynamic effects between the two units, and the energy capture of a single wave energy conversion unit is optimized through a local controller, thereby improving the overall capture efficiency of the dual-unit wave energy array.

[0006] The present invention is achieved by adopting the following technical solutions:

[0007] A distributed clutch control method for a dual-unit wave energy array is proposed, which is characterized by comprising:

[0008] S1, numerical modeling and hydrodynamic analysis of the dual-unit wave energy array model;

[0009] S2, establishing a time-domain motion equation for a dual-unit wave energy array; introducing into the time-domain motion equation an additional inertial force term generated between the wave energy conversion units and a delay term for the radiation effect of the movement of a single wave energy conversion unit on its adjacent devices;

[0010] S3, establishing the state space equation of the dual-unit wave energy array, replacing the convolution term of the time domain motion equation with the state space equation, and calculating the motion state of the dual-unit wave energy array;

[0011] S4, implements distributed clutch control of a dual-unit wave energy array to maximize energy extraction from waves, including:

[0012] Define the Hamiltonian function for each of the two wave energy conversion units in the dual-unit wave energy array ;in, is the equation of motion of a single wave energy conversion unit in a dual-unit wave energy array, is the motion state of the dual-unit wave energy conversion array, To control the command; is the objective function, which represents the functional capture of a single wave energy conversion unit, is a control command for controlling a single wave energy conversion unit; is the PTO damping coefficient of a single wave energy conversion unit; is the movement speed of a single wave energy conversion unit; is the Lagrange multiplier;

[0013] The Hamiltonian function is solved according to the control equation of Lagrange multipliers, and the control criterion of distributed clutch control is obtained according to the solution:

[0014] and ;

[0015] m1 and m2 are the masses of the two wave energy conversion units respectively; 、 They are the additional masses generated by the movement of a wave energy conversion unit itself.

[0016] In some embodiments of the present invention, S2 establishes the time domain motion equation of the dual-unit wave energy array as:

[0017] , ;

[0018] in, 11 and 22 are the additional masses generated by the motion of the two wave energy conversion units, 12 and 21 are the additional masses generated by the movement of a wave energy conversion unit in the heave direction on another wave energy conversion unit; x1, x2, are the displacement, velocity and acceleration of the two wave energy conversion units respectively; is the delay function representing the radiation interaction, is the radiation damping, They represent the self-radiation delay functions of the two wave energy conversion units, indicating the historical impact of the radiation waves generated by the unit's own motion on its own velocity; They represent the delay functions of the radiation effect of the motion of one wave energy conversion unit on another wave energy conversion unit; K is the still water restoring stiffness; is the wave excitation force on the first wave energy conversion unit, is the wave excitation force on the second wave energy conversion unit, where represents the real part of the complex function. represents the transfer function of the wave excitation force, represents the amplitude of the regular wave component j, represents the frequency of the regular wave component j, represents the random phase of the regular wave component j; They represent the reaction forces provided by the two wave energy conversion units from the PTO system, and c represents the damping coefficient of the PTO system.

[0019] In some embodiments of the present invention, the state space equation established in S3 is:

[0020] ;

[0021] in, represents the n×1-dimensional state variable, , , Represent n×n dimensional, n×1 dimensional, and 1×n dimensional state space matrices respectively.

[0022] In some embodiments of the present invention, S3 includes:

[0023] Substitute the established state space equation into the time domain motion equation and define new state variables , transform the time domain motion equation into a linear differential equation:

[0024] ;

[0025] ;

[0026] ;

[0027] ;

[0028] ; and are the net water recovery stiffness of the wave energy conversion unit, respectively;

[0029] ;

[0030] ;

[0031] The Runge-Kutta method is used to solve the motion state X of the dual-unit wave energy array.

[0032] In some embodiments of the present invention, S3 includes:

[0033] Using linear differential equations to approximate the state space equations ; The linear differential equation is: ;

[0034] Perform Laplace transform on the linear differential equation and then perform Fourier transform to obtain:

[0035] ;

[0036] Take the Fourier transform of the delay function representing the radiative interaction:

[0037] ;

[0038] Combining the two Fourier transform results we get:

[0039] , and calculate it to get:

[0040] , ;in, are radiation damping and added mass, respectively, which are calculated by hydrodynamic software;

[0041] according to Calculate p and q, and then get , , .

[0042] In some embodiments of the present invention, S4 includes:

[0043] Solving the Hamiltonian function based on the governing equation of the Lagrange multiplier yields:

[0044] ,

[0045] ,

[0046] ;

[0047] The control criterion of distributed clutch control is obtained according to the solution results.

[0048] In some embodiments of the present invention, during the Hamiltonian solution process, the equation of motion is integrated forward from 0 to T, and the control equation is integrated backward from T to 0, including:

[0049] 1. In Simulate the time and obtain the motion state X of the dual-unit wave energy array by integrating the motion equation from t=0 to t=T;

[0050] 2. Determine the Lagrange multiplier by reversely integrating the governing equation from t=T to t=0 ;

[0051] 3. Given the motion state vector X and the Lagrange multiplier To determine the control sequence , to maximize the Hamiltonian;

[0052] 4. Iterate the process using the updated control sequence until the control sequence convergence.

[0053] In some embodiments of the present invention, the damping coefficient of the PTO in step S2 is optimized using the following formula:

[0054] ;in, is the radiation damping, m is the mass of a single wave energy conversion unit, is the added mass.

[0055] Compared with existing technologies, the advantages and positive effects of the present invention are as follows: the distributed clutch control method for a dual-unit wave energy array proposed in the present invention fully considers the complex hydrodynamic interactions between the wave energy conversion devices in the array in the designed time-domain motion equations, while also being highly practical and easy to implement in actual physical devices. By coordinating the operation of two interconnected distributed controllers, the present invention significantly improves the overall computational efficiency of the system. Compared with traditional single-controller architectures, this method not only optimizes the allocation of computing resources but also effectively improves the overall energy absorption efficiency of the wave energy converter, demonstrating higher energy utilization and system response flexibility.

[0056] Other features and advantages of the present invention will become more apparent after reading the detailed description of the embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0058] Figure 1 This is a schematic diagram of the steps of the distributed clutch control method for a dual-unit wave energy array proposed by the present invention;

[0059] Figure 2 Schematic diagram of the overall structure of the dual-unit wave energy array in the present invention;

[0060] Figure 3 Schematic diagram of the numerical simulation model of the dual-unit wave energy array in the present invention;

[0061] Figure 4 Schematic diagram of the distributed clutch control process in the present invention;

[0062] Figure 5 Schematic diagram of the distributed clutch control principle in the present invention;

[0063] Figure 6 This is a comparison chart of the wave energy capture efficiency of the distributed clutch control method shown in the present invention and the existing uncontrolled and independent control algorithm. DETAILED DESCRIPTION

[0064] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0065] like Figure 1 As shown, the distributed clutch control method for a dual-unit wave energy array proposed in the present invention comprises the following steps:

[0066] S1: Numerical modeling and hydrodynamic analysis of a dual-unit wave energy array model.

[0067] The dual-unit wave energy array consists of two identical, coordinated oscillating float wave energy conversion units. The oscillating float wave energy conversion unit is a device that captures the kinetic energy of waves based on the reciprocating motion of the float with the waves, and then drives the generator to generate electricity through a power take-off (PTO) system. The float, connecting rod, and PTO system are its main components. Among them, the float is connected to the PTO system through a connecting rod. PTO systems mainly include hydraulic, mechanical transmission, hydraulic, pneumatic, linear motor, and hybrid hydraulic types. The present invention selects a hydraulic PTO system, which mainly includes a hydraulic cylinder, a hydraulic motor, and a generator. The piston rod of the hydraulic cylinder is connected to the connecting rod. The hydraulic cylinder drives the hydraulic motor to work, and the hydraulic motor drives the generator to generate electricity.

[0068] Furthermore, the operating principle of the oscillating float wave energy conversion unit is as follows: Under the influence of the periodic motion of waves, the float drives the piston in the hydraulic cylinder to reciprocate vertically via a connecting rod. This reciprocating motion compresses and releases the hydraulic oil in the cylinder, increasing the oil pressure, thereby converting the mechanical energy of the waves into hydraulic energy. The high-pressure hydraulic oil then flows through the pipeline, driving the hydraulic motor, which further converts the hydraulic energy into rotational mechanical energy (i.e., torque and speed of the output shaft). The rotational motion of the output shaft in turn drives a three-phase permanent magnet synchronous generator, which operates based on the law of electromagnetic induction. When the mechanical energy rotates the rotor within the generator, the permanent magnets mounted on the rotor rotate accordingly, disrupting the magnetic field in the stator coils. Since the stator coils consist of three-phase coils, the rotor's rotating magnetic field generates three-phase alternating current with a phase difference of 120° in each coil group. A characteristic of this power generation method is that the rotor speed is synchronized with the frequency of the output current, ensuring stable current output. At the same time, because permanent magnets do not require an external excitation source, the three-phase permanent magnet synchronous generator has high efficiency, simple structure, and low maintenance costs, making it very suitable for the long-term operation of the wave energy conversion unit. This entire process achieves efficient conversion from wave mechanical energy to electrical energy.

[0069] The present invention combines Figure 2 As shown, the dual-unit wave energy array consists of two identical point absorption wave energy conversion units (a first wave energy conversion unit and a second wave energy conversion unit); the wave energy conversion unit is a unit that converts wave energy into electrical energy, mainly composed of a float 11, a connecting rod 12 and a PTO 13. The float 11 adopts a cylindrical floating body with a radius of 2.5m and a draft of 5m. The PTO 13 adopts a hydraulic PTO system, mainly composed of a piston rod, a hydraulic cylinder, a hydraulic motor, and a generator. The piston rod of the hydraulic cylinder is connected to the connecting rod 12, and the hydraulic cylinder drives the The hydraulic motor is in operation, driving the generator to generate electricity. The float 11 reciprocates in the heave direction under the action of waves and is connected to the PTO 13 through the connecting rod 12. The connecting rod 12 drives the hydraulic cylinder piston to rise and fall in the heave direction, increasing the pressure of the hydraulic oil in the hydraulic cylinder chamber. This process converts mechanical energy into hydraulic energy. The hydraulic oil then drives the hydraulic motor, converting the liquid pressure energy in the pipeline into mechanical energy (torque and speed) of the output shaft, and then drives the rear-end generator to generate electricity. The generator uses existing equipment: a three-phase permanent magnet synchronous motor.

[0070] Combine Figure 3 As shown, the present invention uses the GeniE module of the SESAM software to establish only the numerical model of the part below the waterline of the dual-unit wave energy array. In the GeniE module, a numerical model of a dual-unit wave energy array with a radius of 2.5m and a draft of 5m is first established and the wet surface of the dual-unit wave energy array is defined. Then, the wet surface of the dual-unit wave energy array is loaded, and after loading, the grid is divided. Finally, the .fem file can be obtained through calculation and imported into the HydroD module. In the HydroD module, after completing the definition of a series of basic information such as the direction of the wave, the wave frequency, the panel model, etc., the hydrodynamic parameters of the wave energy conversion unit can be calculated. The hydrodynamic parameters here mainly refer to the added mass, radiation damping and the first-order wave force transfer function.

[0071] S2: Establishing a time-domain motion equation for a dual-unit wave energy array; introducing into the time-domain motion equation an additional inertial force term generated between the wave energy conversion units and a delay term of the radiation effect of the movement of a single wave energy conversion unit on its adjacent devices.

[0072] A right-handed coordinate system is used, fixed on the Earth, with the center of the coordinate system fixed on the mean sea surface. The Z axis is positive upward, and the X axis is the direction of propagation of the coastal waves.

[0073] The time domain motion equations of the dual-unit wave energy array are established based on the impulse response theory as shown in formulas (1) and (2):

[0074] (1)

[0075] (2)

[0076] Where m1 and m2 are the masses of the two wave energy conversion units respectively; 11 and 22 are the additional masses generated by the motion of the two wave energy conversion units, 12 and 21 are the additional masses generated by the movement of a wave energy conversion unit in the heave direction on another wave energy conversion unit; x1, x2, are the displacement, velocity and acceleration of the two wave energy conversion units respectively; is the delay function representing the radiation interaction, is the radiation damping, They represent the self-radiation delay functions of the two wave energy conversion units, indicating the historical impact of the radiation waves generated by the unit's own motion on its own velocity; They represent the delay function of the radiation effect of the motion of one wave energy conversion unit on another wave energy conversion unit; K is the still water restoring stiffness. wave,1 and F wave,2 are the wave excitation force of the first wave energy conversion unit and the wave excitation force of the second wave energy conversion unit, respectively. The calculation formulas are as follows:

[0077] (3)

[0078] (4)

[0079] in, represents the real part of the complex function. represents the transfer function of the wave excitation force, represents the amplitude of the regular wave component j, represents the frequency of the regular wave component j, represents the random phase of the regular wave component j; They represent the reaction forces provided by the two wave energy conversion units from the PTO system, and c represents the damping coefficient of the PTO system.

[0080] The linear damping coefficient of PTO can be optimized using formula (5):

[0081] (5)

[0082] in, is the radiation damping, is the mass of a single wave energy conversion unit, is the added mass.

[0083] S3: Establish the state space equation of the dual-unit wave energy array, replace the convolution term of the time domain motion equation with the state space equation, and calculate the motion state of the dual-unit wave energy array.

[0084] The convolution term in the time-domain motion equation of the dual-unit wave energy array in step S2 is replaced by the state-space equation to facilitate the implementation of the control algorithm.

[0085] The state space equation is shown in formula (6):

[0086] (6)

[0087] Using the linear differential equation approximation formula (6) , the linear differential equation is shown in formula (7):

[0088] (7)

[0089] Combining formulas (6) and (7), we can get formula (8):

[0090] ;

[0091] ;

[0092] ; (8)

[0093] in, represents the n×1-dimensional state variable, , , are used to approximate the convolution terms, representing n×n, n×1, and 1×n dimensional state space matrices, respectively. Their expansions (8) are calculated using the system identification method.

[0094] Specifically, we first perform Laplace transform on the linear differential equation (7) to obtain:

[0095] (9)

[0096] The Fourier transform of the delay function representing the radiation interaction, that is, formula (2), is obtained:

[0097] (10)

[0098] Then perform Fourier transform on (9) to obtain:

[0099] (11)

[0100] Combining formulas (10) and (11), we get:

[0101] (12)

[0102] Calculating (12) yields:

[0103] ,

[0104] (13)

[0105] in, are radiation damping and additional mass, respectively, which are calculated by the hydrodynamic software Hydrod. Then p and q are calculated according to formula (13), and then we get , , .

[0106] Substitute the state space equation (6) of the dual-unit wave energy array into its time domain motion equation (1) and use a new state variable:

[0107] (14)

[0108] Rewrite the time domain motion equation of the dual-unit wave energy array into a linear differential equation:

[0109] (15)

[0110] 、 are the motion states of the two wave energy conversion units respectively. Then formula (15) is specifically:

[0111] ;in

[0112] ;

[0113] ;

[0114] ;

[0115] ; and are the net water recovery stiffness of the wave energy conversion unit, respectively;

[0116] ;

[0117] .

[0118] Then, the fourth Runge-Kutta method is used to solve (15) to obtain the motion state of the dual-unit wave energy array.

[0119] S4: Implement distributed clutch control of a dual-unit wave energy array to maximize energy extraction from waves.

[0120] The goal of distributed control is to maximize the energy capture of each WEC unit individually so that their sum is optimized.

[0121] When the phase of the float's velocity is consistent with the phase of the wave excitation force, the energy capture of the wave energy conversion unit will be maximized. The innovative distributed clutch control algorithm of this invention mainly optimizes the control command Control the float, such as Figure 4 As shown, the control action mainly includes loading each PTO system in the dual-unit wave energy array ( ) and uninstall ( ), so that the velocity phase of the float is consistent with the phase of the wave excitation force, so that the energy capture of each wave energy conversion device is maximized, and thus the energy capture of the dual-unit wave energy array is maximized.

[0122] Specifically, the two wave energy conversion units in the dual-unit wave energy array are regarded as two independent single pedals, and clutch control is applied to the two independent wave energy conversion units respectively, that is, the movement of the float is controlled by their respective controllers. The controllers do not work alone, but work in a coordinated manner, that is, the two local controllers communicate and share information at each time step, exchange the motion state and wave excitation force information of their respective wave energy conversion units, and jointly find the optimal control command to control the movement of the float, so that the velocity phase of each float and the phase of the wave excitation force are consistent, so that the power capture of the two independent wave energy conversion units is maximized, and finally the energy of the two wave energy conversion units is superimposed to maximize the total.

[0123] The goal of distributed control of a dual-unit wave energy array is to maximize the energy capture of each wave energy array. This is a constrained optimization problem, and the constraint criterion is the motion equation of the dual-unit wave energy array.

[0124] In the present invention, by introducing Lagrange multipliers, the constraints and the objective function are combined into a Hamiltonian function H, the constraints of the state equation are included in the optimization problem, and the complex constrained optimization problem is transformed into an unconstrained optimization problem. For distributed control, each wave energy conversion unit in the dual-unit wave energy array has its own Hamiltonian function H, as shown in formula (16):

[0125] (16)

[0126] in, is the motion equation of a single wave energy conversion unit in a dual-unit wave energy array; J is the objective function, which represents the functional capture of a single wave energy conversion unit, and its expression is as follows:

[0127] (17)

[0128] is the Lagrange multiplier, following the governing equation (18):

[0129] (18)

[0130] Furthermore, combined with formula (15), the Hamiltonian function H can be written as formula (19):

[0131] (19)

[0132] in, represents a control command for controlling the first wave energy conversion unit, represents the control command for controlling the second wave energy conversion unit, c1 represents the PTO damping coefficient of the first wave energy conversion unit, c2 represents the PTO damping coefficient of the second wave energy conversion unit, Respectively represent the movement speeds of the first wave energy conversion unit and the second wave energy conversion unit.

[0133] Solving the Hamiltonian function (19) by the governing equation (18) yields:

[0134] , , (20)

[0135] According to (20), the control criterion of distributed clutch control can be obtained:

[0136] and (twenty one)

[0137] like Figure 5 As shown, according to the Pontryagin maximum principle, when the Hamiltonian is maximum, there exists an optimal control sequence .

[0138] It should be noted that although the overall constraint criterion of formula (21) corresponds to a single wave energy conversion unit, the determination of the state vector X is based on a dual-unit wave energy array. In other words, each local controller coordinates its work through information sharing and communication, predicts the future state of the wave energy conversion device, and then derives the control command separately. The development of distributed control is based on the observation that Compare is much larger. This suggests that, although the hydrodynamic interaction is crucial for the analysis of the state vector X, it can be neglected in the control criterion if the state vector X is already correctly calculated. Therefore, the hydrodynamic interaction is neglected in the constraint criterion by assuming that all off-diagonal terms are zero.

[0139] It is worth noting that although the motion equation and the control equation of the dual-unit wave energy array are both first-order partial differential equations, they cannot be solved in parallel because the two formulas are at different initial conditions. Specifically, the motion equation is integrated forward from 0 to T, and the control equation is integrated backward from T to 0. An interactive optimization algorithm is used to solve this problem. First, in The simulation is performed at t = 0 and the motion without control is obtained by integrating the equation of motion forward from t = 0 to t = T. The Lagrange multiplier is then determined by integrating the governing equation backward from t = T to t = 0. Finally, given the state vector X and the Lagrange multiplier To determine the control sequence , to maximize the Hamiltonian. The process is iterated using the updated control sequence until the control sequence convergence.

[0140] In a specific embodiment of the present invention, numerical simulations were conducted for an array system consisting of two wave energy converters under three control methods (no control, independent control, and centralized control) to compare their energy capture performance. The incident wave was described using the JONSWAP spectrum, and a wave condition with a significant wave height of 1.4 m and a spectral peak period of 5.5 s was selected. The total simulation duration was 3600 s, with a sampling interval of 0.01 s.

[0141] The wave energy capture efficiency under no control, independent control, and centralized control algorithms is as follows Figure 6 In the absence of control, the energy capture efficiency of the array wave energy conversion device is about 12 kW in 1 hour; in the independent control mode (i.e., the clutch control algorithm is implemented separately for each of the two wave energy conversion devices, such as Figure 5 (As shown in the figure), the energy capture efficiency increased to approximately 31 kW; when the distributed control algorithm was used, the energy capture efficiency was further increased to approximately 42 kW. Compared to the uncontrolled state, the distributed control algorithm increased the energy capture efficiency by 250%; compared to the independent control mode, the increase was 35.5%. This shows that the distributed control algorithm proposed in this invention significantly improves wave energy capture efficiency, fully demonstrating its outstanding performance advantages.

[0142] It should be noted that, in the specific implementation process, the above-mentioned control part can be implemented by a hardware processor executing computer execution instructions in software form stored in the memory, which will not be elaborated here. The programs corresponding to the actions performed by the above-mentioned control circuit can be stored in the system's computer-readable storage medium in software form, so that the processor can call and execute the operations corresponding to the above modules.

[0143] The computer-readable storage medium mentioned above may include volatile memory, such as random access memory; may also include non-volatile memory, such as read-only memory, flash memory, hard disk or solid-state drive; may also include a combination of the above types of memory.

[0144] The processor mentioned above can also be a collective term for multiple processing elements. For example, the processor can be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices (PLDs), discrete gate or transistor logic devices (LDDs), discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor, etc., and can also be a special-purpose processor.

[0145] It should be pointed out that the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by ordinary technicians in this technical field within the essential scope of the present invention should also fall within the scope of protection of the present invention.

Claims

1. A distributed clutch control method for a dual-unit wave energy array, characterized in that: include: S1, numerical modeling and hydrodynamic analysis of the dual-unit wave energy array model; S2, establishing a time-domain motion equation for a dual-unit wave energy array; introducing into the time-domain motion equation an additional inertial force term generated between the wave energy conversion units and a delay term for the radiation effect of the movement of a single wave energy conversion unit on its adjacent devices; S3, establishing the state space equation of the dual-unit wave energy array, replacing the convolution term of the time domain motion equation with the state space equation, and calculating the motion state of the dual-unit wave energy array; S4, implements distributed clutch control of a dual-unit wave energy array to maximize energy extraction from waves, including: Define the Hamiltonian function for each of the two wave energy conversion units in the dual-unit wave energy array ;in, is the equation of motion of a single wave energy conversion unit in a dual-unit wave energy array, is the motion state of the dual-unit wave energy conversion array, To control the command; is the objective function, which represents the functional capture of a single wave energy conversion unit, is a control command for controlling a single wave energy conversion unit; is the PTO damping coefficient of a single wave energy conversion unit; is the movement speed of a single wave energy conversion unit; is the Lagrange multiplier; The Hamiltonian function is solved according to the control equation of Lagrange multipliers, and the control criterion of distributed clutch control is obtained according to the solution: and ; m1 and m2 are the masses of the two wave energy conversion units respectively; 、 They are the additional masses generated by the movement of a wave energy conversion unit itself.

2. The distributed clutch control method for a dual-unit wave energy array according to claim 1, characterized in that: The time domain motion equation of the dual-unit wave energy array established in step S2 is: ， ； in, 11 and 22 are the additional masses generated by the motion of the two wave energy conversion units, 12 and 21 are the additional masses generated by the motion of a wave energy conversion unit in the heave direction on another wave energy conversion unit; x1, x2, are the displacement, velocity and acceleration of the two wave energy conversion units respectively; is the delay function representing the radiation interaction, is the radiation damping, They represent the self-radiation delay functions of the two wave energy conversion units, indicating the historical impact of the radiation waves generated by the unit's own motion on its own velocity; They represent the delay functions of the radiation effect of the motion of one wave conversion unit on another wave conversion unit; is the hydrostatic recovery stiffness; is the wave excitation force on the first wave energy conversion unit, is the wave excitation force on the second wave energy conversion unit, where represents the real part of the complex function. represents the transfer function of the wave excitation force, represents the amplitude of the regular wave component j, represents the frequency of the regular wave component j, represents the random phase of the regular wave component j; They represent the reaction forces provided by the two wave energy conversion units from the PTO system, and c represents the damping coefficient of the PTO system.

3. The distributed clutch control method for a dual-unit wave energy array according to claim 1, characterized in that: The state space equation established in S3 is: ； in, represents the n×1-dimensional state variable, , , Represent n×n dimensional, n×1 dimensional, and 1×n dimensional state space matrices respectively.

4. The distributed clutch control method for a dual-unit wave energy array according to claim 3, characterized in that S3 include: Substitute the established state space equation into the time domain motion equation and define new state variables , transform the time domain motion equation into a linear differential equation: ;in, ； ； ； ； ； ; and are the hydrostatic recovery stiffness of the wave energy conversion unit; is the PTO damping coefficient of the first wave energy conversion unit, is the PTO damping coefficient of the second wave energy conversion unit; The Runge-Kutta method is used to solve the motion state X of the dual-unit wave energy array.

5. The distributed clutch control method for a dual-unit wave energy array according to claim 4, characterized in that: S3 includes: Using linear differential equations to approximate the state space equations ; The linear differential equation is: ; Perform Laplace transform on the linear differential equation and then perform Fourier transform to obtain: ； Take the Fourier transform of the delay function representing the radiative interaction: ； Combining the two Fourier transform results we get: , and calculate it to get: ， ;in, are radiation damping and added mass, respectively, which are calculated by hydrodynamic software; according to Calculated , q, and then we get , , .

6. The distributed clutch control method for a dual-unit wave energy array according to claim 4, characterized in that S4 include: Solving the Hamiltonian function based on the governing equation of the Lagrange multiplier yields: ， ， ； The control criterion of distributed clutch control is obtained according to the solution results.

7. The distributed clutch control method for a dual-unit wave energy array according to claim 6, characterized in that: During the Hamiltonian solution, the equations of motion are integrated forward from 0 to T, and the control equations are integrated backward from T to 0, including: exist Simulate the state X of the dual-unit wave energy array by integrating the motion equation from t=0 to t=T; Determine the Lagrange multiplier by integrating the governing equation backward from t = T to t = 0 ; Given the motion state vector X and the Lagrange multiplier To determine the control sequence , to maximize the Hamiltonian; The process is iterated using the updated control sequence until the control sequence convergence.

8. The distributed clutch control method for a dual-unit wave energy array according to claim 1, characterized in that: In step S2, the damping coefficient of the PTO is optimized using the following formula: ;in, is the radiation damping, m is the mass of the wave energy conversion unit, is the added mass.

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