Wave energy device control method and system based on real sea state wave loads

Abstract

The application provides a wave energy power generation device control method and system based on actual sea state wave load, and the control method comprises the following steps: selecting a motion-power response coupling model of a wave energy power generation device based on actual sea state wave load data; using the motion-power response coupling model to calculate the optimal value of a control parameter combination of the wave energy power generation device under actual sea state; determining a control strategy for a PTO unit and a power generation unit based on the motion response of a floater unit corresponding to the actual sea state wave load data and the optimal value of the control parameter combination, wherein the control strategy comprises an adaptive variable damping control strategy and a self-protection variable damping control strategy. The control method and system provided by the application can select the optimal control strategy based on the actual sea state wave load to control the wave energy power generation device.

Description

Technical Field

[0001] This application belongs to the field of wave energy power generation technology, specifically, it provides a control method and system for a wave energy power generation device based on actual sea conditions and wave loads. Background Technology

[0002] Wave energy generation devices are devices that convert wave energy into electrical energy using floats and associated PTO (Power Take Off) and power generation equipment. Since the frequency, wave height, and wavelength of incident waves have random time-varying characteristics, optimizing the mechanical and electrical control parameters of wave energy generation devices for actual sea conditions is the key to improving the final power generation efficiency of wave energy generation devices.

[0003] To date, numerous power control strategies have been proposed, among which typical strategies include damping constant strategies, model prediction strategies, and maximum power control strategies. The damping constant strategy involves fixing the damping before the wave energy generator operates at sea. It is suitable for areas with stable sea conditions, but it lacks good power generation efficiency for changing sea conditions, making it unfeasible both economically and in terms of reliability. The model prediction strategy uses a large amount of data and a matched model to predict sea waves, which places high demands on the hardware required for processing. The maximum power control strategy aims to keep the generator at its maximum power output, but its calculation requires a long convergence time and does not consider whether the maximum power output can meet the safety requirements of the coupled system formed by the float-PTO-generator.

[0004] Therefore, there is a need for a control method and control system that can comprehensively consider the coupling effect between the hydrodynamic characteristics, mechanical structure, and electrical parameters of wave energy power generation devices, as well as the safety of the mechanical structure, under actual sea conditions and wave loads. Summary of the Invention

[0005] The purpose of this application is to solve the problems existing in the prior art and provide a control method and control system for a wave energy power generation device. This control method and control system can perform adaptive variable damping control on the wave energy power generation device based on the actual sea conditions and can protect the wave energy power generation device under extreme sea conditions.

[0006] The first aspect of this application provides a control method for a wave energy power generation device based on actual sea condition wave loads. The wave energy power generation device includes a float unit, a PTO unit, and a power generation unit. The control method includes the following steps:

[0007] The motion-power response coupling model of the wave energy power generation device is selected based on real sea condition wave load data, wherein the real sea condition wave load data includes real-time measurements of wave frequency ω, wave height h and wavelength L, and the motion-power response coupling model includes an accurate model and a fast model.

[0008] The optimal value of the control parameter combination of the wave energy generation device under actual sea conditions is calculated using the motion-power response coupling model, wherein the control parameter combination includes the load damping of the PTO unit and the equivalent damping of the power generation unit.

[0009] The control strategy for the PTO unit and the power generation unit is determined based on the motion response of the float unit corresponding to the optimal value of the combination of real sea state wave load data and control parameters. The control strategy includes an adaptive variable damping control strategy and a self-protective variable damping control strategy.

[0010] Furthermore, when the actual sea condition wave load data meets the conditions for rapid calculation, the rapid model is used to calculate the optimal value of the control parameter combination of the wave energy power generation device under the actual sea condition; otherwise, the accurate model is used to calculate the optimal value of the control parameter combination of the wave energy power generation device under the actual sea condition.

[0011] Preferably, the rapid calculation conditions are:

[0012] ω>ω L or h / L < r H ,

[0013] Where, ω L r H This is a preset threshold for rapid calculation.

[0014] Furthermore, the precise model includes a coupled float motion response module, a PTO control module, and a motor control module; the float motion response module determines the motion response of the float unit based on the actual sea condition wave load data, the load damping set by the PTO control module, and the equivalent damping set by the motor control module; the motor control module determines the power response of the power generation unit based on its set equivalent damping, the motion response of the float unit, and the load damping set by the PTO control module.

[0015] Furthermore, the rapid model is a set of coupled equations describing the motion response of the buoy unit and the power response of the power generation unit under actual sea conditions, as shown in the following equations:

[0016]

[0017] Among them, m, z, These represent the mass, displacement, velocity, and acceleration of the float in the float unit, respectively, F. r F e Fs F PTO F gen These represent the effects of radiation force, wave excitation force, water recovery force, PTO damping force, and power generation unit on the float, respectively, in μ. 33 , λ 33 These represent the added mass of the radiative force and the radiative damping, respectively, C FK A and K represent the coefficient of wave excitation force and wave amplitude, respectively. w k is the stiffness of the water purification restoring force. PTO C PTO These represent the stiffness and load damping of the PTO element, respectively, in m. gen C gen P gen These are the equivalent mass, equivalent damping, and equivalent power of the power generation unit, respectively.

[0018] Preferably, when the motion response of the float unit corresponding to the optimal value of the control parameter combination does not exceed the structural strength threshold of the wave energy power generation device, the adaptive variable damping control strategy is used to control the PTO unit and the power generation unit; otherwise, the self-protection variable damping control strategy is used to control the PTO unit and the power generation unit.

[0019] Furthermore, the adaptive variable damping control strategy includes the following steps:

[0020] The optimal power generation of the power generation unit is calculated based on the optimal value of the control parameter combination corresponding to the actual sea condition wave load data.

[0021] If the relative deviation between the optimal power generation and the actual power generation of the power generation unit does not exceed the preset power deviation threshold, then the load damping of the PTO unit and the equivalent damping of the power generation unit remain unchanged; otherwise, the load damping of the PTO unit and the equivalent damping of the power generation unit are adjusted using the optimal value of the control parameter combination.

[0022] Furthermore, the self-protected variable damping control strategy includes the following steps:

[0023] S1, keep the equivalent damping of the power generation unit unchanged, and increase the load damping of the PTO unit;

[0024] S2, calculate the motion response of the float unit using the equivalent damping and load damping determined in step S1;

[0025] S3. If the motion response of the float unit calculated in step S2 exceeds the structural strength threshold of the wave energy power generation device, then return to step S1; otherwise, proceed to step S4.

[0026] S4. If the load damping determined in step S1 does not exceed the upper limit of the load damping design of the PTO unit, then the load damping of the PTO unit is readjusted according to the load damping determined in step S1; otherwise, the PTO unit is self-locked.

[0027] Preferably, the control method further includes the following steps:

[0028] The database saves the actual sea condition wave load data and the optimal values ​​of the corresponding control parameter combinations, the motion response of the float unit, and the power response of the power generation unit to the database; and...

[0029] The optimal values ​​of the control parameter combinations and the motion response of the float unit are retrieved from the database corresponding to the actual sea state wave load data.

[0030] A second aspect of this application provides a control system for a wave energy generation device based on actual sea condition wave loads. The wave energy generation device includes a float unit, a PTO unit, and a power generation unit, comprising:

[0031] The model selection unit selects the motion-power response coupling model of the wave energy power generation device based on real sea condition wave load data. The real sea condition wave load data includes real-time measurements of wave frequency ω, wave height h, and wavelength L. The motion-power response coupling model includes an accurate model and a fast model.

[0032] The optimal value determination unit uses the motion-power response coupling model to calculate the optimal value of the control parameter combination of the wave energy power generation device under actual sea conditions, wherein the control parameter combination includes the load damping of the PTO unit and the equivalent damping of the power generation unit.

[0033] The control unit determines the control strategy for the PTO unit and the power generation unit based on the motion response of the float unit corresponding to the optimal value of the combination of real sea state wave load data and control parameters. The control strategy includes an adaptive variable damping control strategy and a self-protective variable damping control strategy.

[0034] The embodiments of this application provide a control method and system for wave energy generation devices based on actual sea conditions and wave loads. This method comprehensively considers the hydrodynamic, transmission, and power generation processes of the wave energy generation device to construct a motion-power response coupling model capable of accurate or rapid calculation. Based on actual sea conditions, the most suitable model is selected to search for optimal control parameters, significantly improving the search speed while ensuring computational accuracy. This effectively meets the need for real-time control parameter optimization during the use of the wave energy generation device. Furthermore, considering device safety, a control strategy prioritizing power generation efficiency or safety is selected to control the wave energy generation device, enabling early warning and self-protection under extreme sea conditions. Attached Figure Description

[0035] Figure 1 A schematic diagram of the system architecture of a wave energy power generation device;

[0036] Figure 2 This is a flowchart of a wave energy generation device control method based on actual sea condition wave loads provided in an embodiment of this application;

[0037] Figure 3 The flowchart is provided below for a control method of a wave energy generation device based on wave loads under actual sea conditions, according to some specific embodiments.

[0038] Figure 4 This is a schematic diagram illustrating the optimal value of the control parameter combination of a wave energy generation device obtained using an accurate model according to an embodiment of this application;

[0039] Figure 5 This is a flowchart illustrating the implementation of the self-protected variable damping control strategy according to an embodiment of this application.

[0040] Figure 6 This is a framework diagram of a wave energy power generation device control system based on actual sea condition wave loads, provided according to an embodiment of this application. Detailed Implementation

[0041] The present application will now be further described based on preferred embodiments and with reference to the accompanying drawings.

[0042] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, in the description of this application, in order to distinguish different units, the terms "first," "second," etc. are used in this specification, but these are not limited by the manufacturing order, nor should they be construed as indicating or implying relative importance. Their names may differ in the detailed description and claims of this application.

[0043] The vocabulary used in this specification is for illustrative purposes and is not intended to limit the scope of this application. It should also be noted that, unless otherwise expressly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection via an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of these terms in this application.

[0044] Figure 1 This is a schematic diagram of the structure of an existing wave energy power generation device, such as... Figure 1 As shown, the device consists of a float unit, a PTO unit, and a power generation unit. The float unit is a cylindrical or other shaped float that rises and falls vertically with the incident waves. The PTO unit transmits the rise and fall of the float to the power generation unit through a damping adjustable mechanism such as springs or hydraulic pressure, and the generator in the power generation unit converts the rise and fall of the float into electrical energy output.

[0045] Utilization in actual marine environments Figure 1 The wave energy generation device shown faces at least the following problems when generating electricity:

[0046] a. The energy conversion system consisting of float-PTO-generator is a coupled system containing various types of dynamic processes. In particular, the mechanical damping parameters of PTO and the electrical damping parameters of generator can only achieve efficient conversion of wave energy to electrical energy when they are matched with the load characteristics generated by the incident wave at the float. Therefore, it is necessary to quickly determine the optimal control parameters based on the real-time changing wave load in the actual sea conditions.

[0047] b. Due to the complexity and variability of the actual marine environment, in some sea areas where efficient power generation can be achieved, the high wave energy is both beneficial to the output of electrical energy and may damage the mechanical and transmission structures of wave energy power generation devices. Therefore, the highest power generation efficiency cannot be simply used as the sole criterion for determining control parameters. Instead, power generation efficiency and equipment safety should be comprehensively considered to find the control parameters that are most suitable for the actual sea conditions.

[0048] Therefore, this application provides a control method for a wave energy power generation device based on wave loads under actual sea conditions, such as... Figure 2 As shown, the method includes the following steps:

[0049] Step 100: Select the motion-power response coupling model of the wave energy power generation device based on real sea condition wave load data, wherein the real sea condition wave load data includes real-time measured values ​​of wave frequency ω, wave height h and wavelength L, and the motion-power response coupling model includes an accurate model and a fast model.

[0050] Step 200: Calculate the optimal value of the control parameter combination of the wave energy generation device under actual sea conditions using the motion-power response coupling model, wherein the control parameter combination includes the load damping of the PTO unit and the equivalent damping of the power generation unit.

[0051] Step 300: Based on the motion response of the float unit corresponding to the optimal value of the actual sea condition wave load data and control parameter combination, determine the control strategy for the PTO unit and the power generation unit. The control strategy includes an adaptive variable damping control strategy and a self-protective variable damping control strategy.

[0052] In step 100, the actual sea conditions are assessed, and a coupling model is selected to search for the optimal control parameters of the wave energy power generation device. Then, in step 200, a suitable coupling model is used to search for the optimal control parameters that match the actual sea conditions. Furthermore, in step 300, it is determined again whether the buoy meets the overall safety requirements of the power generation device when operating under the optimal parameters, so as to finally determine whether to adopt a control strategy that prioritizes power generation efficiency or safety. Furthermore, steps 100 to 300 can be repeated at certain time intervals to adjust the control strategy of the wave energy power generation device in a timely manner according to changes in the actual sea conditions.

[0053] The following combination Figure 3 The preferred embodiments shown provide a detailed description of the specific implementation process of each step.

[0054] <Obtaining Real-World Wave Load Data>

[0055] like Figure 3 As shown, in this embodiment, the incident waves are monitored online by sensors installed on the base of the wave energy generation device to obtain real sea condition wave load data. Specifically, wave meters, wave height meters and other equipment known to those skilled in the art can be used, combined with image acquisition devices such as cameras, to collect data such as the wave frequency ω (wave angular frequency), wave height h and wavelength L of the incident waves.

[0056] <Category Judgment 1>

[0057] After obtaining the above-mentioned actual sea condition wave load data, as follows Figure 3 As shown, the first judgment (category judgment 1) is made on the collected real sea state wave load data. This judgment is used to determine which calculation model to use to obtain the optimal value of the control parameter combination.

[0058] In the embodiments of this application, the optimal value of the control parameter combination is searched with the goal of achieving the maximum power output of the wave energy power generation device. Specifically, the power generation process of the wave energy power generation device includes the hydrodynamic process of the float unit moving under the excitation of the incident wave, the damped motion process of the PTO unit, and the kinetic energy-electric energy conversion process of the power generation unit. Without considering the impact of wave intensity on the structural strength and other safety aspects of the device, the control parameters of each unit of the power generation device (e.g., the damping parameters of the PTO unit and the resistance parameters of the power generation unit) can be determined through parameter optimization and search to achieve the ideal maximum power output. The control parameters corresponding to achieving the maximum power output are the optimal values ​​of the control parameter combination.

[0059] In the embodiments of this application, different motion-power response coupling models can be used to calculate the motion response of the float and the final power response of the generated electricity under the control of various control parameters, depending on the wave load conditions of different sea conditions. Specifically, the motion-power coupling model includes a complex calculation model and a fast calculation model.

[0060] Among them, the complex calculation model can calculate the coupling effect between the float unit, PTO unit and power generation unit with high accuracy by establishing accurate models of each unit of the wave energy power generation device. However, it has a large amount of calculation and a long calculation time. Therefore, under certain conditions, the load data of the incident wave can be used to construct a fast model describing the hydrodynamic-damped motion-power generation of wave energy power generation. This model can greatly improve the calculation speed without losing the calculation accuracy, so as to achieve a balance between calculation accuracy and calculation efficiency and ensure that the control parameters of the wave energy power generation device can be quickly adjusted according to the actual sea conditions.

[0061] In some preferred embodiments, when the actual sea state wave load data meets the conditions for rapid calculation, a rapid model is used to calculate and obtain the optimal value of the control parameter combination; otherwise, an accurate model is used to calculate and obtain the optimal value of the control parameter combination. For example, when the wave frequency ω of the incident wave is greater than a preset frequency-related rapid calculation threshold ω... L At this time, the waves are in a high-frequency oscillation state. If an accurate model is used for calculation, the computational workload will increase significantly, which is not conducive to the rapid search for the optimal value of the control parameter combination. For example, when the ratio of the incident wave height to the wavelength h / L is less than the preset rapid calculation threshold r related to the wave size, the calculation will be more difficult. H When the nonlinearity of the wave is relatively weak, a simplified fast model can be used for calculation to greatly improve the search speed for the optimal combination of control parameters.

[0062] ω L and r HThe choice of ω can be determined by comprehensively considering the modeling complexity of the accurate model and the calculation speed of the fast model for wave loads in real sea conditions. For example, in some embodiments, ω can be set. L = 1.26 rad / s, r H =0.125. In other embodiments, ω can also be determined based on the actual sea conditions. L and r H .

[0063] Furthermore, in some preferred embodiments, such as Figure 3 As shown, the acquired real sea state wave load data, along with the optimal values ​​of the control parameter combinations calculated based on the acquired data, the motion response of the buoy unit, and the power response of the power generation unit, can be saved to the database. In subsequent control processes, the newly acquired real sea state wave load data is compared with the data stored in the database. If the same real sea state wave load data already exists in the database, the optimal values ​​of the control parameter combinations and the motion response of the buoy unit corresponding to the real sea state wave load data are directly retrieved from the database to further improve the acquisition speed of the optimal values ​​of the control parameter combinations.

[0064] (1-1) Accurate Model

[0065] Figure 4 A framework diagram of an accurate model for calculating the motion-generation coupling process of a wave energy power generation device is shown, as follows: Figure 4 As shown, the accurate model includes a coupled float motion response module, a PTO control module, and a motor control module. In actual implementation, various forms of float structure models, PTO transmission models, and motor power generation models known to those skilled in the art can be used to construct the above-mentioned accurate model. The float motion response module receives real sea state wave load data input through the CHANGING-WAVE module and couples with the PTO control module and the motor control module. Its displacement response, velocity response, and force response are jointly determined by the real sea state wave load and parameters such as the load damping of the PTO control module and the resistance of the motor control module (in order to maintain consistency with the rapid model described later, the resistance and other parameters of the motor control module can also be converted into equivalent damping parameters). At the same time, the power output by the motor control module is also jointly determined by the motion response output by the float motion response module, the load damping of the PTO control module unit, and its own equivalent damping.

[0066] Furthermore, existing commercial software such as AMESIM can be used, or programs can be written to batch change the load damping and equivalent damping to obtain the motion of the float and the power generation of the generator when the wave energy power generation device is controlled by different combinations of control parameters under actual sea conditions. Using a multi-parameter search algorithm, with the maximum power generation as the objective function, the optimal value of the control parameter combination can be determined through search.

[0067] Furthermore, in some preferred embodiments, such as Figure 4 As shown, the accurate model also includes a database for storing the above-mentioned real sea condition wave load data and the optimal values ​​of the corresponding control parameter combinations and the buoy motion response, and directly obtains the optimal values ​​of the control parameter combinations when the real sea condition wave loads stored in the database occur subsequently.

[0068] (1-2) Fast Model

[0069] As mentioned above, when the actual sea state wave load data meets the conditions for rapid calculation, a simplified rapid model can be used to calculate and search for the optimal values ​​of control parameters. Specifically, in the embodiments of this application, the buoy motion is simplified to vertical heave motion, and its motion state is affected by multiple forces. Specifically, it can be represented by the rapid model as follows:

[0070]

[0071] The above fast model represents the motion response (including displacement z and velocity) of a float of mass m. and acceleration The resultant force is composed of multiple forces, among which F r F e F s F PTO F gen These represent the effects of radiation force, wave excitation force, water recovery force, PTO damping force, and power generation unit on the float, respectively, in μ. 33 , λ 33 These represent the added mass of the radiative force and the radiative damping, respectively, C FK A and K represent the coefficient of wave excitation force and wave amplitude, respectively. w k is the stiffness of the water purification restoring force. PTO C PTO These represent the stiffness and load damping of the PTO element, respectively, in m. gen C gen P gen These are the equivalent mass, equivalent damping, and equivalent power of the power generation unit, respectively.

[0072] It should be noted that traditional hydrodynamic models of float motion generally only consider the case where the load damping of the PTO system is simplified to a constant. However, through analysis of the power generation process of wave energy generators, it was found that parameters such as the resistance of the generator are fed back to the PTO system, thus forming a coupling with the heave motion of the float. Therefore, in order to better improve the power generation efficiency, in the embodiments of this application, the motor of the power generation unit is also designed with variable parameters, and its resistance value and other parameters are converted into equivalent damping parameters, thereby forming the above-mentioned model that can describe the coupling effect between the float-PTO-generator.

[0073] Specifically, the dynamic differential equation in the above equation can be transformed into the float motion transfer function shown in the following equation using the Laplace transform:

[0074]

[0075] Where s is the complex frequency of the Laplace transform, and M(t) is the acceleration-related term. The Laplace transform converts the differential equation into a linear equation, and then C is changed... PTO C gen The above transfer function equation is solved quickly, and the corresponding equivalent power P is calculated using the solution. gen By using the maximization of equivalent power as the objective function, the optimal C can be searched and determined. PTO C gen combination.

[0076] <Category Judgment 2>

[0077] like Figure 3 As shown, after obtaining the optimal value of the control parameter combination corresponding to the actual sea state wave load data, a second category judgment is required. This judgment is mainly based on the consideration of the safety of the power generation equipment. The reason is that although the optimal value of the control parameter combination can obtain the maximum power output, the above optimal control parameter combination may cause the float's motion state, such as displacement, motion state or force, to exceed the strength limit that the power generation device can withstand when facing extreme sea states, resulting in damage to the power generation device. Therefore, it is necessary to further judge the safety of the power generation device to determine the priority of power generation efficiency and equipment safety.

[0078] Specifically, such as Figure 3As shown, in category judgment 2, the motion response of the float unit corresponding to the optimal value of the control parameter combination and the structural strength threshold of the wave energy power generation device are compared. If the structural strength threshold is not exceeded, an adaptive variable damping control strategy is used to control the PTO unit and the power generation unit; otherwise, a self-protective variable damping control strategy is used. The structural strength threshold can be determined based on the actual mechanical structure and specifications of each unit constituting the wave energy power generation device. For example, in some specific embodiments, if the float displacement exceeds 0.5 meters, the velocity exceeds 0.45 meters / second, or the force exceeds 15,000 Newtons, it can be judged that the wave energy power generation device is at risk and a self-protective variable damping control strategy should be used to control it.

[0079] (2-1) Adaptive variable damping control strategy

[0080] Specifically, when using an adaptive variable damping control strategy to control a wave energy power generation device, the optimal value of the control parameter combination corresponding to the actual sea condition wave load data is determined based on an accurate model or a fast model, or extracted from the database, and the optimal power generation of the power generation unit is calculated using it.

[0081] If the relative deviation between the calculated optimal power generation and the actual power generation of the power generation unit does not exceed 20%, then the load damping of the PTO unit and the equivalent damping of the power generation unit remain unchanged; otherwise, the load damping of the PTO unit and the equivalent damping of the power generation unit are adjusted using the optimal value of the calculated combination of control parameters.

[0082] (2-2) Self-protected variable damping control strategy

[0083] Specifically, such as Figure 5 As shown, when using a self-protected variable damping control strategy to control a wave energy generation device, the following steps are performed:

[0084] S1, keep the equivalent damping of the power generation unit unchanged, and increase the load damping of the PTO unit;

[0085] S2, calculate the motion response of the float unit using the equivalent damping and load damping determined in step S1;

[0086] S3. If the motion response of the float unit calculated in step S2 exceeds the structural strength threshold of the wave energy power generation device, then return to step S1; otherwise, proceed to step S4.

[0087] S4. If the load damping determined in step S1 does not exceed the upper limit of the load damping design of the PTO unit, then the load damping of the PTO unit is readjusted according to the load damping determined in step S1; otherwise, the PTO unit is self-locked.

[0088] In the above steps, when the motion response of the float exceeds the structural strength threshold of the wave energy power generation device, first, by gradually increasing the load damping of the PTO unit, the maximum power generation is selected on the premise of reducing the structural strength risk of the power generation device to meet safety requirements. Further, when the load damping at the time of meeting safety requirements has exceeded the design upper limit of the PTO system (that is, when the design upper limit of the load damping of the PTO unit cannot meet the safety requirements), it means that the actual sea conditions at this time cannot ensure the safe operation of the power generation device. At this time, the PTO unit needs to be self-locked to ensure the safety of the power generation device.

[0089] Some preferred embodiments of the present application further provide a control system for a wave energy power generation device based on real sea condition wave loads. Figure 6 The framework schematic diagram of the control system is shown, as Figure 6 shown, the control system includes a model selection unit, an optimal value determination unit, and a control unit.

[0090] The model selection unit selects a motion-power response coupling model of the wave energy power generation device based on real sea condition wave load data. Among them, the real sea condition wave load data includes real-time measurement values of the wave frequency ω, wave height h, and wavelength L of the wave, and the motion-power response coupling model includes an accurate model and a fast model;

[0091] The optimal value determination unit uses the motion-power response coupling model to calculate the optimal value of the control parameter combination of the wave energy power generation device under real sea conditions. Among them, the control parameter combination includes the load damping of the PTO unit and the equivalent damping of the power generation unit;

[0092] The control unit determines the control strategies for the PTO unit and the power generation unit based on the real sea condition wave load data and the motion response of the float unit corresponding to the optimal value of the control parameter combination. The control strategies include an adaptive variable damping control strategy and a self-protection variable damping control strategy.

[0093] In some specific embodiments, the model selection unit, the optimal value determination unit, and the control unit of the control system can be in the form of executable programs or functions, installed in the embedded operating system supporting the wave energy power generation device, and called and executed by its threads to implement their respective functions. The above implementation methods are already known to those skilled in the art and will not be elaborated here.

[0094] The above has made a detailed introduction to the specific implementation manners of the present application. For those skilled in the art of this technology, without departing from the principle of the present application, several improvements and modifications can still be made to the present application, and these improvements and modifications also belong to the protection scope of the claims of the present application.

Claims

1. A wave energy power plant control method based on real sea state wave loads, said wave energy power plant comprising a floater unit, a PTO unit and a power generation unit, characterized by, The method comprises the following steps: A motion-power response coupling model of a wave energy power generation device is selected based on real sea condition wave load data, wherein the real sea condition wave load data includes real-time measured values of wave frequency , wave height , and wave length of the wave, and the motion-power response coupling model includes an accurate model and a fast model; calculating the optimal value of the control parameter combination of the wave energy power generation device in the real sea state using the motion-power response coupling model, wherein the control parameter combination comprises the load damping of the PTO unit and the equivalent damping of the power generation unit; determining the control strategy for the PTO unit and the power generation unit based on the real sea state wave load data and the motion response of the floater unit corresponding to the optimal value of the control parameter combination, wherein the control strategy comprises an adaptive variable damping control strategy and a self-protection variable damping control strategy; the precise model comprises a floater motion response module, a PTO control module and a motor control module which are coupled with each other; the floater motion response module determines the motion response of the floater unit based on the real sea state wave load data, the load damping set by the PTO control module and the equivalent damping set by the motor control module; the motor control module determines the power response of the power generation unit based on the equivalent damping set by the motor control module, the motion response of the floater unit and the load damping set by the PTO control module; the fast model is a coupling equation group for describing the motion response of the floater unit and the power response of the power generation unit in the real sea state, and is shown in the following formula: , wherein, , , , are the mass, displacement, velocity and acceleration of the buoy in the buoy unit, respectively, , , , , are the radiation force, wave excitation force, net water restoring force, PTO damping force and equivalent force of the power take-off unit, respectively, , are the added mass and radiation damping of the radiation force, respectively, , are the coefficient and wave amplitude of the wave excitation force, respectively, is the stiffness of the net water restoring force, , are the stiffness and load damping of the PTO unit, respectively, , , are the equivalent mass, equivalent damping and equivalent power of the power take-off unit, respectively.

2. The wave energy power generation device control method based on real sea state wave load according to claim 1, wherein: when the real sea state wave load data meets the fast calculation condition, the optimal value of the control parameter combination of the wave energy power generation device in the real sea state is calculated using the fast model, otherwise the optimal value of the control parameter combination of the wave energy power generation device in the real sea state is calculated using the precise model.

3. The wave energy power plant control method based on real sea condition wave loads according to claim 2, characterized in that, the fast calculation condition is: or , wherein , is a preset fast computation threshold.

4. The wave energy power generation device control method based on real sea state wave load according to claim 1, wherein: when the motion response of the floater unit corresponding to the optimal value of the control parameter combination does not exceed the structural strength threshold of the wave energy power generation device, the adaptive variable damping control strategy is used to control the PTO unit and the power generation unit, otherwise the self-protection variable damping control strategy is used to control the PTO unit and the power generation unit.

5. The method of claim 1, wherein, the adaptive variable damping control strategy comprises the following steps: calculating the optimal power generation power of the power generation unit based on the optimal value of the control parameter combination corresponding to the real sea state wave load data; if the relative deviation of the optimal power generation power and the actual power generation power of the power generation unit does not exceed the preset power deviation threshold, the load damping of the PTO unit and the equivalent damping of the power generation unit are kept unchanged, otherwise the load damping of the PTO unit and the equivalent damping of the power generation unit are adjusted using the optimal value of the control parameter combination.

6. The wave energy power plant control method based on real sea condition wave loads according to claim 4, characterized in that, the self-protection variable damping control strategy comprises the following steps: S1, keeping the equivalent damping of the power generation unit unchanged and increasing the load damping of the PTO unit; S2, calculating the motion response of the floater unit using the equivalent damping and the load damping determined in step S1; S3, if the motion response of the floater unit calculated in step S2 exceeds the structural strength threshold of the wave energy power generation device, returning to execute step S1, otherwise executing step S4; S4, if the load damping determined in step S1 does not exceed the upper limit of the load damping design of the PTO unit, readjusting the load damping of the PTO unit with the load damping determined in step S1, otherwise self-locking the PTO unit.

7. The wave energy power plant control method based on real sea condition wave loads according to claim 1, characterized by, Further comprising the following steps: saving the optimal value of the control parameter combination, the motion response of the floater unit and the power response of the power generation unit corresponding to the real sea state wave load data to a database; and calling the optimal value of the control parameter combination and the motion response of the floater unit corresponding to the real sea state wave load data from the database.

8. A wave energy device control system based on real sea state wave loads, the wave energy device comprising a floater unit, a PTO unit and a power generation unit, characterized in that, controlling the wave energy power generation device using the real sea state wave load based wave energy power generation device control method of claim 1, comprising: a model selection unit configured to select a motion-power response coupling model of the wave energy power plant based on real sea state wave load data, wherein the real sea state wave load data comprises real-time measured values of wave frequency , wave height , and wave length of the wave, and the motion-power response coupling model comprises an accurate model and a fast model; an optimal value determination unit for calculating the optimal value of the control parameter combination of the wave energy power generation device in the real sea state using the motion-power response coupling model, wherein the control parameter combination comprises the load damping of the PTO unit and the equivalent damping of the power generation unit; a control unit for determining the control strategy of the PTO unit and the power generation unit based on the motion response of the floater unit corresponding to the real sea state wave load data and the optimal value of the control parameter combination, wherein the control strategy comprises the adaptive variable damping control strategy and the self-protection variable damping control strategy.

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