Integrated simulation system and method for floating wind-wave integrated device

Abstract

The present invention belongs to the field of marine renewable energy utilization, and in particular, to an integrated simulation system and method for a floating wind-wave integrated device. The simulation system includes a floating body time domain simulation module, a connection constraint simulation module, a PTO simulation module, and an energy acquisition assessment module. The influence of the connection constraint system and the PTO system on the dynamic behavior of the floating wind-wave integrated device is accurately considered to achieve the full process simulation of the wave energy-electric energy conversion of the floating wind-wave integrated device. The present invention derives and gives the mathematical expressions of the connection constraint system and the PTO system between the floating platform and the wave energy conversion device. The proposed system makes up for the defects of the existing mainstream floating body time domain software in the simulation of the multi-body connection constraint system and the PTO system, and has better universality and fidelity; the proposed method provides a reliable tool for the design optimization of the floating wind-wave integrated device, which can promote the engineering application process of the floating wind-wave integrated device.

Description

Technical Field

[0001] The invention relates to the field of marine renewable energy utilization, and in particular to an integrated simulation system and method for a floating wind-wave integrated device. Background Art

[0002] There is a natural correlation between sea breeze and waves. In sea areas rich in wind energy resources, the wave energy reserves are also very considerable, and it is feasible to capture energy simultaneously. Therefore, scientifically integrating offshore wind turbines and wave energy conversion devices, constructing wind-wave integrated devices, and forming a comprehensive utilization model of "wind leading waves" can overcome the development limitations of a single energy type and effectively promote the industrialization of marine renewable energy. As offshore resource development approaches saturation, the development of floating wind-wave integrated devices to capture high-quality wind and wave energy in the deep sea is an inevitable trend in the joint development of wind and waves.

[0003] Compared with floating wind turbines, the introduction of wave energy conversion devices makes the coupling between substructures of wind-wave integrated devices more complex, and research on integrated devices around the world is in the exploratory stage. Compared with physical model tests, numerical simulation can consider more complex environmental conditions and a wider range of parameter spaces, and is the main tool in the design and development stage of floating wind-wave integrated units.

[0004] Wave energy conversion devices are usually deployed in arrays in wind-wave integrated devices. Each wave energy conversion device has a motion constraint relationship and an energy take-off system (Power Take-Off, PTO) with the floating platform. Effective simulation of the constraint relationship and the PTO system between the two is crucial for the true reproduction of the wave-to-electricity conversion process of the wind-wave integrated device. However, how to clarify the force relationship between different structures, establish a simulation system with better universality and higher fidelity, and then realize the accurate evaluation of the wave energy conversion power of the wind-wave integrated device is a technical problem that needs to be solved in this field. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide an integrated simulation system and method for a floating wind-wave integrated device. By establishing a universal and fidelity simulation system, the simulation problems of multi-body constraint systems and PTO systems are solved, and the entire process of wave-to-electricity conversion of a floating wind-wave integrated device can be accurately reproduced.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] An integrated simulation system for a floating wind-wave integrated device, written in Python, Matlab, Fortran or C programming languages, includes:

[0008] The floating body time domain simulation module, relying on the existing mature floating body time domain calculation software, establishes a numerical model of the floating wind-wave integrated device, receives the constraint force and PTO reaction force caused by the connection constraint between the wave energy conversion device and the floating platform and the existence of the PTO system at each time step, and incorporates it into the solution of the motion response equation group of the floating platform and several wave energy conversion devices, and obtains the real-time position information of the center of gravity of the floating platform and several wave energy conversion devices in the global coordinate system, including displacement, velocity and acceleration. The above-mentioned position information and step time information will be output through the existing external force interface.

[0009] A connection constraint simulation module is provided, which compiles simulation codes of a multi-body connection constraint system based on programming languages ​​such as Python, Matlab, Fortran or C. Specifically, the module receives the position information of the floating platform and a plurality of wave energy conversion devices at the center of gravity in the global coordinate system transmitted by the floating body time domain simulation module at each time step, considers the specific motion constraint types (relative surge, relative sway, relative heave, relative roll, relative pitch and relative bow), and obtains the relative motion information and constraint reaction force / torque information of the floating platform and the wave energy conversion device according to the derived series of derivation formulas (mathematical expression of the multi-body connection constraint system) of the present invention, calculates the relative motion information and constraint reaction force / torque information of the floating platform and the wave energy conversion device, and transmits the constraint reaction force / torque information to the floating body time domain simulation module so as to consider the influence of the connection constraint system in the process of solving the dynamic equation group of the floating platform and the plurality of wave energy conversion devices.

[0010] PTO simulation module, which also compiles the simulation code of the multi-body PTO system based on the above-mentioned programming language. Specifically, this module obtains the relative motion information of the floating platform and the wave energy conversion device based on the multi-body constraint system at each time step, considers the specific PTO type (direct drive, hydraulic, etc.), calculates the PTO force / torque information exerted on the floating platform and the wave energy conversion device, and passes this information to the floating body time domain simulation module to consider the influence of the PTO system in the process of solving the dynamic equations of the floating platform and several wave energy conversion devices.

[0011] The energy acquisition assessment module receives the relative speed and PTO force information of the floating platform and several wave energy conversion devices output by the connection constraint simulation module and the PTO simulation module at each time step, and obtains the real-time power generation power of the floating wind-wave integrated device according to the power calculation formula, thereby completing the real-time reproduction of the wave-electricity conversion process of the floating wind-wave integrated device.

[0012] A method for constructing an integrated simulation system for a floating wind-wave integrated device comprises the following steps:

[0013] Step 1) Build a floating body time domain simulation module in the existing mature floating body time domain calculation software.

[0014] Step 1-1) defines the force relationship between the floating platform and several wave energy conversion devices, and establishes the motion response equations of the above structures based on the Cummins equation.

[0015] In step 1-2, the floating body time domain calculation software reads the calculation results of the floating platform and several wave energy devices obtained by the existing floating body frequency domain calculation software, including the mass matrix, hydrodynamics and hydrostatics coefficients of the above structures, inputs the viscosity correction coefficients of the floating platform and several wave energy devices, and establishes a mooring system model based on the mooring analysis function of the software (common floating body time domain calculation software has built-in mooring calculation function) or establishes a real-time data transmission channel with other existing mooring analysis software (for example: MAP++, MoorDy and other open source mature mooring analysis modules) to achieve coupling, and establishes a wind turbine model based on the wind turbine analysis function of the software (existing technology, common floating body time domain calculation software has built-in wind turbine simulation function) or establishes a wind turbine simulation program with other existing wind turbine analysis software (for example: OpenFAST and other open source mature wind turbine analysis modules) to establish a real-time data transmission channel to achieve coupling.

[0016] In steps 1-3, the floating body time domain calculation software obtains the instantaneous wave excitation force, wave radiation force, hydrostatic restoring force and viscosity correction force acting on the floating platform and each wave energy conversion device based on the frequency domain calculation results and viscosity correction coefficients of the floating platform and several wave energy devices read; based on the mooring analysis function or the coupled mooring analysis software, and the wind turbine analysis function or the coupled wind turbine analysis software, the instantaneous mooring force on the floating platform and the additional force caused by the wind turbine are obtained.

[0017] Steps 1-4) activate the external force interface of the floating body time domain calculation software, which is usually compiled based on Python, Matlab, Fortran or C language, and can transmit to the outside the posture information obtained by solving the time domain dynamic equations of the floating platform and several wave energy conversion devices, and incorporate the received external force information into the solution of the time domain dynamic equations, thereby considering the influence of the multi-body constraint connection system and the PTO system on the dynamic behavior of the floating wind-wave integrated device.

[0018] Step 2) Build a connection constraint simulation module based on Python, Matlab, Fortran or C language, obtain the constraint force applied to the floating platform and the wave energy conversion device at each time step, and realize the simulation of the multi-body constraint connection system.

[0019] Step 2-1) establishes respective local coordinate systems with the center of gravity of the floating platform and the wave energy conversion device as the origin, and determines the spatial positions of all connection constraint points between the wave energy conversion device and the floating platform in the global coordinate system. The positions of the connection constraint points in the platform local coordinate system and the corresponding wave energy conversion device local coordinate system remain unchanged.

[0020] In step 2-2, the mathematical expression of the instantaneous relative position of the spatial constraint points on all wave energy conversion devices in the local coordinate system of the platform (the instantaneous relative displacement of the wave energy conversion device and the floating platform) is derived, and the instantaneous displacement of the center of gravity of all wave energy conversion devices and the floating platform in the global coordinate system transmitted by the floating body time domain simulation module is further converted into the instantaneous relative displacement of the two, and the above motion information is passed to the PTO simulation module.

[0021] In step 2-3, the connection stiffness matrix is ​​used to describe the motion constraint relationship between the wave energy conversion device and the floating platform. The connection system is simplified to a connection spring with infinite stiffness at the constraint point. According to the specific motion constraint type, the specified relative motion degree of freedom is released, and the corresponding connection stiffness is set to 0. Then, the instantaneous constraint reaction force at all constraint points in the local coordinate system of the platform is obtained by multiplying the connection stiffness matrix with the relative displacement between the wave energy conversion device and the floating platform.

[0022] In step 2-4), the force translation theorem and three-dimensional coordinate transformation are applied to transform the instantaneous constraint reaction force at the connection constraint point in the local coordinate system of the platform into the equivalent constraint reaction force at the center of gravity of the platform and all wave energy conversion devices in the global coordinate system, and then transmitted to the floating body time domain simulation module.

[0023] Step 3) Build a PTO simulation module and energy acquisition evaluation module based on Python, Matlab, Fortran or C language, obtain the PTO force applied to the floating platform and the wave energy conversion device at each time step, realize the simulation of the multi-body PTO system, and obtain the real-time power generation of all wave energy conversion devices for specific PTO types.

[0024] Step 3-1), derive the mathematical expression of the instantaneous relative velocity of all spatial constraint points on the wave energy conversion device in the local coordinate system of the platform (the instantaneous relative velocity between the wave energy conversion device and the floating platform), receive the displacement information transmitted by the connection constraint simulation module, and calculate the instantaneous relative velocity between all wave energy conversion devices and the floating platform.

[0025] In step 3-2), according to the specific type of PTO, a mathematical expression is given to calculate the instantaneous PTO force on all constraint points in the local coordinate system of the platform.

[0026] In step 3-3), the force translation theorem and three-dimensional coordinate transformation are also applied to transform the instantaneous PTO force received at the connection constraint point in the local coordinate system of the platform into the equivalent PTO force received at the center of gravity of the platform and all wave energy conversion devices in the global coordinate system, and then transmitted to the floating body time domain simulation module and energy acquisition assessment module.

[0027] Step 4) With the floating body time domain simulation module as the hub, the constraint system simulation module, the PTO simulation module and the energy acquisition assessment module are coupled through the external force interface, and the dynamic equations of the floating platform and the wave energy conversion device are solved step by step to reproduce the real-time process of extracting wave energy by the floating wind-wave integrated device.

[0028] Step 4-1), at each time step, the floating body time domain simulation module drives the connection constraint simulation module through the external force interface. After the connection constraint module processes the relative motion information between the floating platform and the wave energy conversion device, it drives the PTO simulation module to calculate the relative speed between the floating platform and the wave energy conversion device and the PTO force, and then drives the energy acquisition assessment module to complete the calculation of real-time power generation.

[0029] Step 4-2), after the constraint simulation module, PTO simulation module and energy acquisition assessment module are connected and calculated, the constraint force and PTO force information are transmitted to the floating body time domain simulation module, and it is driven to solve the dynamic equations for the next time step to realize the closed-loop coupling of each module.

[0030] Beneficial effects of the invention:

[0031] The present invention establishes and couples a floating body time domain simulation module, a connection constraint simulation module, a PTO simulation module and an energy acquisition assessment module, accurately considers the influence of the connection constraint system and the PTO system on the dynamic behavior of the floating wind-wave integrated device, and realizes the full process simulation of the wave energy-electric energy conversion of the floating wind-wave integrated device. The present invention derives and gives the mathematical expressions of the connection constraint system and the PTO system between the floating platform and the wave energy conversion device. On this basis, the proposed system makes up for the defects of the existing mainstream floating body time domain software in the simulation of the multi-body connection constraint system and the PTO system, and has better universality and fidelity; the proposed method provides a reliable tool for the design optimization of the floating wind-wave integrated device, which can promote the engineering application process of the floating wind-wave integrated device. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic diagram showing the structure of the integrated simulation system of the present invention;

[0033] Figure 2 is a diagram showing the communication relationship between different modules of the present invention;

[0034] Figure 3is a schematic diagram showing a floating wind-wave integrated device in an example;

[0035] Figure 4 It is a time history comparison diagram showing the longitudinal displacement of the floating platform under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method;

[0036] Figure 5 It is a time history comparison diagram showing the heave displacement of a floating platform under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in the present invention and the mature and disclosed floating wind-wave integrated device simulation method;

[0037] Figure 6 It is a time history comparison diagram showing the pitch displacement of the floating platform under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method;

[0038] Figure 7 It is a time history comparison diagram showing the relative displacement of the wave energy conversion device and the floating platform under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method;

[0039] Figure 8 It is a time history comparison diagram showing the relative speed of the wave energy conversion device and the floating platform under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method;

[0040] Fig. 9 It is a time history comparison diagram showing the PTO damping force of the wave energy conversion device under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method;

[0041] Fig.10 It is a time comparison diagram showing the power output of the wave energy conversion device under regular waves, linear PTO and pulley-guide rail constraint connection using the integrated simulation method introduced in this patent and the mature and disclosed floating wind-wave integrated device simulation method.

[0042] In the figure, 1. wind turbine, 2. floating platform, 3. wave energy conversion device, 4. pulley-guide rail constraint. DETAILED DESCRIPTION

[0043] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0044] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical contents.

[0045] An integrated simulation system for a floating wind-wave integrated device is disclosed herein, which is written in a programming language such as Python, Matlab, Fortran or C. Figure 1 As shown, it includes a floating body time domain simulation module, a constraint connection simulation module, a PTO simulation module and an energy acquisition assessment simulation module. The floating body time domain simulation module relies on the existing mature floating body time domain simulation software, and can construct a corresponding numerical simulation model according to the specific form of the floating wind-wave integrated device, and obtain the solution results of the motion response equation group of the floating platform 2 and the wave energy conversion device 3; the constraint connection simulation module is equivalent to the corresponding connection stiffness matrix according to the specific form of the constraint connection system between the floating platform 2 and the wave energy conversion device 3, and gives the mathematical expression of the relative displacement and the constraint force, and converts it into a programming language to realize the simulation of the constraint connection system; the PTO simulation module is based on the specific form of the PTO system between the floating platform 2 and the wave energy conversion device 3, gives the mathematical expression of the relative speed and the PTO force, and converts it into a programming language to realize the simulation of the PTO system; the energy acquisition assessment module obtains and saves the calculation results of the constraint connection simulation system and the PTO simulation system in real time, and then obtains the power generation of each wave energy conversion device, such as Figure 2 The integrated simulation system of the present invention is described below in combination with specific methods.

[0046] In the mature floating body time domain simulation software, the corresponding numerical model is established according to the specific form of the floating wind-wave integrated device, and the corresponding environmental parameters and simulation control parameters are set, such as wave elements, time step, simulation duration, etc. The multi-body motion response equations of the floating platform and several wave energy conversion devices are as follows:

[0047] ;

[0048] in, The floating platform and IThe mass matrix of a Wave Energy Converter (WEC); The floating platform and I The instantaneous acceleration matrix of a wave energy conversion device; and The floating platform and I The instantaneous wave excitation force of a wave energy conversion device; and The floating platform and I The instantaneous wave radiation force of a wave energy conversion device; and The floating platform and I The instantaneous hydrostatic restoring force of a wave energy conversion device; The instantaneous mooring force caused by the mooring system of the floating platform; and The floating platform and I The viscous correction force of a wave energy conversion device is usually described by a quadratic damping force or a linear damping force model; and The floating platform and I The external forces to which the wave energy conversion device is subjected include the additional forces caused by the presence of wind turbines on the floating platform. , restraint connection system and PTO system for floating platforms and I The instantaneous restraining force generated by a wave energy conversion device , and instantaneous PTO force , .

[0049] The floating body time domain calculation software reads the mass properties, hydrodynamics and hydrostatics results of the floating platform and all wave energy conversion devices obtained by the existing floating body frequency domain calculation software to calculate the floating platform and the first I Transient wave excitation force on a wave energy conversion device , , wave radiation force , , hydrostatic recovery , ; Accept the input viscosity correction coefficient of the floating platform and the wave energy conversion device to calculate the corresponding viscosity correction force , Based on its own mooring analysis function or coupled mooring analysis software, and wind turbine analysis function or coupled wind turbine analysis software, the instantaneous mooring force on the floating platform is obtained. and additional forces caused by wind turbines ; Floating platform and I The instantaneous constraint force and PTO force on each wave energy conversion device are calculated by the constraint connection simulation module and the PTO simulation module through the external force interface. After the above instantaneous force is known, the floating body time domain calculation software solves the operation response equations of the floating platform and the wave energy conversion device, and obtains the motion displacement, velocity and acceleration of the center of gravity of the floating platform and each wave energy conversion device in the global coordinate system, and then transmits the above posture information to the outside in real time through the external force interface. In the simulation initialization stage, that is, when the step time is 0, the floating body time domain calculation software has not yet received the instantaneous external force information transmitted by the external force interface. The initial value of the instantaneous external force is set to 0 and is brought into the solution of the multi-body motion response equations to obtain the posture information of the floating platform and the wave energy conversion device, and then drives the connection constraint simulation module and the PTO simulation module through the external force interface in the next time step.

[0050] After the external force interface receives the position information of the floating platform and the wave energy conversion device, the relative motion information of the wave energy conversion device and the floating platform is obtained, and the connection constraint reaction force and PTO reaction force acting on the floating platform and the wave energy conversion device are obtained by combining the specific connection constraint type and PTO type. Specifically, the connection constraint relationship between the floating platform and the wave energy conversion device is described using the connection stiffness matrix in the local coordinate system. The connection constraint system is simplified to a connection spring with infinite stiffness at the displacement constraint point. At the same time, the center of gravity of the floating platform and the wave energy conversion device are used as the origin of their respective local coordinate systems, such as Figure 3 The positions of the constraint points on the floating platform and the wave energy conversion device are fixed relative to their respective local coordinate systems, that is, and are all known constants. I The relative displacement between the wave energy conversion device and the floating platform It can be calculated by the following formula derived from this patent:

[0051] ;

[0052] in is the Euler angle coordinate transformation matrix, which can be calculated by the following formula:

[0053] ;

[0054] The constraint reaction force at the constraint point in the global coordinate system is as follows:

[0055]

[0056] in, is the spring stiffness matrix connecting the Ith constraint point. If only relative heave motion is allowed between the wave energy conversion device and the floating platform, then is set to 0.

[0057] Furthermore, the restraint reaction force at the restraint point is converted to the center of gravity of the floating platform and the wave energy conversion device, as shown in the following formula:

[0058] ;

[0059] ;

[0060] Therefore, the above formula is converted into a programming code in the external force interface to obtain the equivalent constraint force acting on the center of gravity of the floating platform and the wave energy conversion device, and then returned to the mature floating body time domain simulation software to solve the multi-body motion response equations to achieve accurate simulation of the constraint connection system.

[0061] Taking the linear direct drive PTO system as an example, the floating platform and the I PTO forces at the restraint points of a wave energy converter and Assumed to be relative displacement With relative speed A linear function of is shown in the following formula:

[0062] .

[0063] The present invention derives a relative speed calculation formula between the wave energy conversion device and the floating platform, as shown below:

[0064] .

[0065] Furthermore, the floating platform and I The equivalent PTO force on the center of gravity of a wave energy conversion device is shown in the following formula:

[0066]

[0067] .

[0068] Similarly, the obtained force is returned to the mature floating body time domain simulation software to solve the multi-body motion response equations and achieve accurate simulation of the PTO system.

[0069] In addition, the real-time power generation of the device can be calculated based on the relative motion information of the wave energy conversion device and the PTO force in the local coordinate system. The energy acquisition evaluation module established in the external force interface records the above key information in the output text for further energy acquisition analysis of the floating wind-wave integrated device.

[0070] The existing common floating body time domain simulation software usually has a dynamic link library based on Fortran / C language or Matlab and Python data interface, such as Ansys-AQWA, WEC-Sim and other software, which can be selected to build the floating body time domain simulation module according to the requirements for the simulation accuracy of the floating platform and the wave energy conversion device. The floating body time domain analysis software selected in the floating body time domain simulation module can return the displacement and velocity at the center of gravity of the floating platform and the wave energy conversion device through the dynamic link library based on Fortran / C language or Matlab and Python data interface at each solution time step, receive the equivalent constraint force and equivalent PTO force additionally applied at the center of gravity of the platform and the wave energy conversion device, and add them to the solution of the multi-body motion response equation.

[0071] The following is a detailed description with reference to specific embodiments. It should also be understood that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by technicians in this field based on the above content of the present invention belong to the scope of protection of the present invention. In addition, various floating body time domain calculation software, as existing mature technologies, can theoretically be used as the floating body time domain simulation module of the present invention, but the floating body time domain calculation software is diverse and it is impractical to list them all. Therefore, the present invention only takes Ansys-AQWA as an example to introduce the operation process in detail, but the present invention is not limited to this. The integrated simulation of the floating wind-wave integrated device combined with other floating body time domain calculation software and the system and method described in the present invention should be within the scope of protection of the present invention.

[0072] In the specific implementation process, the method of the present invention is applied to simulate a typical floating wind-wave integrated device. The wind turbine adopts a 5MW wind turbine of the US Renewable Energy Laboratory NREL, and the floating platform adopts the Deepcwind floating platform of the European OC4 project, which is simplified to a cylindrical float with a radius of 6m and a draft of 3m, and is arranged on the axis of the semi-submersible platform. Figure 3Firstly, according to the information of the wind turbine 1, floating platform 2 and wave energy conversion device 3, a corresponding frequency domain numerical simulation model is established in the AQWA-LINE software to calculate the mass matrix, hydrodynamics and hydrostatics information of the above structures. The AQWA-NAUT time domain calculation software automatically reads the frequency domain calculation results, and builds a time domain calculation model of the floating wind-wave integrated device based on its own mooring analysis function and coupling with other wind turbine analysis software. In each time step, the connection constraint simulation module and the PTO system simulation module are driven by the Python external force interface, and the position information of the floating platform and the wave energy conversion device are transmitted to them at the same time; the connection constraint simulation module and the PTO system simulation module calculate the equivalent constraint force and PTO force at the center of gravity of the floating platform and the wave energy conversion device according to the specific connection constraint type and PTO type, and return them to the AQWA-NAUT time domain calculation software to solve the multi-body motion response equation group of the wind-wave integrated device, obtain the new position information of the floating platform and the wave energy conversion device, and start a new time step iterative calculation until the specified simulation time is reached; the energy acquisition evaluation module in the Python external force interface records the real-time power generation of the floating wind-wave integrated device at each time step, and outputs the corresponding energy acquisition data in text form after the simulation is completed. In order to verify the reliability and accuracy of the method of the present invention, the applicant conducted a feasibility comparison test to compare the numerical simulation results of the existing mature public simulation method (Fender function provided by AQWA) with the results of the integrated method introduced by the present invention.

[0073] Figures 4 to 10 The results of the comparison of the motion response of the floating platform, the relative motion of the wave energy conversion device, the PTO damping force and the output power predicted by the method of the present invention and the mature and public floating wind-wave integrated device simulation method under the conditions of regular waves with a period of 10s and a wave height of 1.5m and PTO linear damping are given. It can be seen that the results predicted by the two methods are exactly the same, which means that the system and method of the present invention can accurately evaluate the influence of the constraint connection system and the PTO system of the floating wind-wave integrated device on the dynamic behavior of the integrated device, and accurately reproduce the whole process of wave-electric energy conversion. In addition, although the disclosed AQWA-Fender method is effective, its setting is very cumbersome. For each wave energy conversion device, a large number of Fenders need to be set in the floating body time domain simulation software to limit the additional degrees of freedom motion and PTO system of the wave energy conversion device. With the increase in the number of wave energy conversion devices, the large number of Fendes will lead to the instability of the AQWA-NAUT solution of the floating platform and wave energy conversion device motion response equations. The AQWA-Fender method cannot also consider other complex PTO systems. The method of the present invention has high stability, good universality, and is easy to develop and expand, and is undoubtedly an excellent alternative to the AQWA-Fender method.

[0074] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A floating wind-wave integrated device integrated simulation system, characterized in that: include: The floating body time domain simulation module establishes a numerical model of the floating wind-wave integrated device, receives the constraint force and PTO reaction force caused by the connection constraint between the wave energy conversion device and the floating platform and the existence of the PTO system at each time step, and incorporates them into the solution of the multi-body motion response equation group of the floating platform and several wave energy conversion devices, and obtains the real-time position information of the center of gravity of the floating platform and several wave energy conversion devices in the global coordinate system. The above-mentioned position information and step time information will be output through the existing external force interface; The multi-body motion response equations are: ， in, The floating platform and I The mass matrix of a wave energy conversion device; The floating platform and I The instantaneous acceleration matrix of a wave energy conversion device; and The floating platform and I The instantaneous wave excitation force of a wave energy conversion device; and The floating platform and I The instantaneous wave radiation force of a wave energy conversion device; and The floating platform and I The instantaneous hydrostatic restoring force of a wave energy conversion device; The instantaneous mooring force caused by the mooring system of the floating platform; and The floating platform and I The viscous correction force of a wave energy conversion device is usually described by a quadratic damping force or a linear damping force model; and The floating platform and I The external forces to which the wave energy conversion device is subjected include the additional forces caused by the presence of wind turbines on the floating platform. , restraint connection system and PTO system for floating platforms and I The instantaneous restraining force generated by a wave energy conversion device , and instantaneous PTO force , ; A connection constraint simulation module, which receives the position information of the floating platform and several wave energy conversion devices at the center of gravity in the global coordinate system transmitted by the floating body time domain simulation module at each time step, considers the specific motion constraint type, and calculates the relative motion information and constraint reaction force / torque information of the floating platform and the wave energy conversion device according to a series of derivation formulas of the relative motion and constraint reaction force / torque between the floating platform and the wave energy conversion device, and transmits the constraint reaction force / torque information to the floating body time domain simulation module so as to consider the influence of the connection constraint system in the process of solving the dynamic equation group of the floating platform and the several wave energy conversion devices; The PTO simulation module calculates the PTO force / torque information on the floating platform and the wave energy conversion device based on the relative motion information of the floating platform and the wave energy conversion device obtained by the multi-body constraint system at each time step, taking into account the specific PTO type, and passes this information to the floating body time domain simulation module to consider the influence of the PTO system in the process of solving the dynamic equations of the floating platform and several wave energy conversion devices; The energy acquisition assessment module receives the relative speed and PTO force information of the floating platform and several wave energy conversion devices output by the connection constraint simulation module and the PTO simulation module at each time step, and obtains the real-time power generation power of the floating wind-wave integrated device according to the power calculation formula, thereby completing the real-time reproduction of the wave-electricity conversion process of the floating wind-wave integrated device.

2. The integrated simulation system of the floating wind-wave integrated device according to claim 1, characterized in that: The real-time position and posture information includes displacement, velocity and acceleration.

3. The integrated simulation system of the floating wind-wave integrated device according to claim 1, characterized in that: The motion constraint types include relative surge, relative sway, relative heave, relative roll, relative pitch and relative pitch.

4. A method for constructing an integrated simulation system for a floating wind-wave integrated device, characterized in that: The following steps are involved: Step (1), constructing a floating body time domain simulation module in the floating body time domain calculation software; The following steps are involved: Step (1-1), clarify the force relationship between the floating platform and several wave energy conversion devices, and establish a multi-body motion response equation group based on the Cummins equation; The multi-body motion response equations are: ， in, The floating platform and I The mass matrix of a wave energy conversion device; The floating platform and I The instantaneous acceleration matrix of a wave energy conversion device; and The floating platform and I The instantaneous wave excitation force of a wave energy conversion device; and The floating platform and I The instantaneous wave radiation force of a wave energy conversion device; and The floating platform and I The instantaneous hydrostatic restoring force of a wave energy conversion device; The instantaneous mooring force caused by the mooring system of the floating platform; and The floating platform and I The viscous correction force of a wave energy conversion device is usually described by a quadratic damping force or a linear damping force model; and The floating platform and I The external forces to which the wave energy conversion device is subjected include the additional forces caused by the presence of wind turbines on the floating platform. , restraint connection system and PTO system for floating platforms and I The instantaneous restraining force generated by a wave energy conversion device , and instantaneous PTO force , ; Step (1-2), the floating body time domain calculation software reads the calculation results of the floating platform and the plurality of wave energy devices obtained by the existing floating body frequency domain calculation software, including the mass matrix, the hydrodynamic and hydrostatic coefficients, inputs the viscosity correction coefficients of the floating platform and the plurality of wave energy devices, establishes a mooring system model based on the mooring analysis function of the software or establishes a real-time data transmission channel with other existing mooring analysis software to achieve coupling, and establishes a wind turbine model based on the wind turbine analysis function of the software or establishes a wind turbine simulation program with other existing wind turbine analysis software to achieve coupling; Step (1-3), the floating body time domain calculation software obtains the instantaneous wave excitation force, wave radiation force, hydrostatic restoring force and viscosity correction force acting on the floating platform and each wave energy conversion device based on the read frequency domain calculation results and viscosity correction coefficient of the floating platform and the plurality of wave energy devices; obtains the instantaneous mooring force on the floating platform and the additional force caused by the wind turbine based on the mooring analysis function or the coupled mooring analysis software, and the wind turbine analysis function or the coupled wind turbine analysis software; Step (1-4), activating the external force interface of the floating body time domain calculation software, which is compiled based on Python language, Matlab language, Fortran language or C language, and can transmit to the outside the posture information obtained by solving the time domain dynamic equations of the floating platform and several wave energy conversion devices, and incorporate the received external force information into the solution of the time domain dynamic equations, thereby considering the influence of the multi-body constraint connection system and the PTO system on the dynamic behavior of the floating wind-wave integrated device; Step (2) building a connection constraint simulation module based on Python, Matlab, Fortran or C language, obtaining the constraint force applied to the floating platform and the wave energy conversion device at each time step, and realizing the simulation of the multi-body constraint connection system; Step (3), building a PTO simulation module and an energy acquisition evaluation module based on Python, Matlab, Fortran or C language, obtaining the PTO force applied to the floating platform and the wave energy conversion device at each time step, realizing the simulation of the multi-body PTO system, and obtaining the real-time power generation of all wave energy conversion devices for specific PTO types; Step (4) takes the floating body time domain simulation module as the core, connects the constraint system simulation module, the PTO simulation module and the energy acquisition assessment module through the external force interface coupling, and reproduces the real-time process of extracting wave energy by the floating wind-wave integrated device by stepping through the multi-body motion response equations of the floating platform and the wave energy conversion device.

5. The method for constructing an integrated simulation system for a floating wind-wave integrated device as claimed in claim 4, characterized in that: The step (2) specifically includes the following steps: Step (2-1), establishing respective local coordinate systems with the center of gravity of the floating platform and the wave energy conversion device as the origin, and determining the spatial positions of all connection constraint points between the wave energy conversion device and the floating platform in the global coordinate system, and the positions of the connection constraint points in the local coordinate system of the platform and the local coordinate system of the corresponding wave energy conversion device remain unchanged; Step (2-2), deriving the mathematical expression of the instantaneous relative position of the spatial constraint points on all wave energy conversion devices in the local coordinate system of the platform, further converting the instantaneous displacement of the center of gravity of all wave energy conversion devices and the floating platform in the global coordinate system transmitted by the floating body time domain simulation module into the instantaneous relative displacement of the two, and transmitting the above motion information to the PTO simulation module; Step (2-3), using the connection stiffness matrix to describe the motion constraint relationship between the wave energy conversion device and the floating platform, the connection system is simplified to a connection spring with infinite stiffness at the constraint point, and according to the specific motion constraint type, the specified relative motion degree of freedom is released, and the corresponding connection stiffness is set to 0, and then the instantaneous constraint reaction force at all constraint points in the local coordinate system of the platform is obtained by multiplying the connection stiffness matrix with the relative displacement between the wave energy conversion device and the floating platform; Step (2-4) applies the force translation theorem and three-dimensional coordinate transformation to transform the instantaneous constraint reaction force at the connection constraint point in the local coordinate system of the platform into the equivalent constraint reaction force at the center of gravity of the platform and all wave energy conversion devices in the global coordinate system, and then transmits it to the floating body time domain simulation module.

6. The method for constructing an integrated simulation system for a floating wind-wave integrated device as claimed in claim 4, characterized in that: The step (3) specifically includes the following steps: Step (3-1), deriving a mathematical expression of the instantaneous relative velocity of all spatial constraint points on the wave energy conversion device in the local coordinate system of the platform, receiving the displacement information transmitted by the connection constraint simulation module, and calculating the instantaneous relative velocity of all wave energy conversion devices and the floating platform; Step (3-2), according to the specific type of PTO, a mathematical expression is given to calculate the instantaneous PTO force on all constraint points in the local coordinate system of the platform; In step (3-3), the force translation theorem and three-dimensional coordinate transformation are also applied to transform the instantaneous PTO force received at the connection constraint point in the local coordinate system of the platform into the equivalent PTO force received at the center of gravity of the platform and all wave energy conversion devices in the global coordinate system, and then transmitted to the floating body time domain simulation module and the energy acquisition assessment module.

7. The method for constructing an integrated simulation system for a floating wind-wave integrated device as claimed in claim 4, characterized in that: The step (4) specifically includes the following steps: Step (4-1), at each time step, the floating body time domain simulation module drives the connection constraint simulation module through the external force interface. After the connection constraint module processes the relative motion information between the floating platform and the wave energy conversion device, it drives the PTO simulation module to calculate the relative speed between the floating platform and the wave energy conversion device and the PTO force, and then drives the energy acquisition assessment module to complete the calculation of the real-time power generation; Step (4-2), after the constraint simulation module, PTO simulation module and energy acquisition assessment module are connected and calculated, the constraint force and PTO force information are transmitted to the floating body time domain simulation module, and it is driven to solve the dynamic equations for the next time step, so as to realize the closed-loop coupling of each module.

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