Wave energy device based on cam driving type PTO system and simulation method thereof

Abstract

The invention belongs to the field of ocean energy utilization, and particularly discloses a wave energy device based on a cam driving type PTO system and a simulation method of the wave energy device. The wave energy device comprises a cam driving device and a hydraulic energy storage system which are mounted on the jacket platform, the cam driving device is in contact with the hydraulic energy storage system, and the cam driving device is connected with an oscillation floater outside the jacket platform; the hydraulic energy storage system is connected with the power generation system; the cam driving device comprises two parallel bases installed on the jacket platform, a large gear and a small gear which are meshed with each other are installed between the two bases through a rotating shaft, and the rotating shaft of the small gear extends out of the bases and is fixedly provided with a cam. The outer edge of the cam is in contact with a plunger of the hydraulic energy storage system; the oscillating floater and a rotating shaft of the large gear are fixedly installed. According to the method, the coupling numerical model is constructed through the coupling process of the series cam driving device and the wave energy device, and is used for overall optimization development of the PTO device based on cam driving, and the working performance is reasonably estimated.

Description

Technical Field

[0001] The invention belongs to the field of ocean energy utilization, in particular to a wave energy device based on a cam-driven PTO system and a simulation method thereof. Background Art

[0002] At present, in the research work related to oscillating float wave energy devices, most scholars tend to simplify the PTO (short for Power take-off) system in the device (a system in which a wave energy device converts mechanical energy into electrical energy), such as using linear damping, ignoring the nonlinear effects caused by the drive device between the PTO system and the wave energy device system, and cannot effectively guide engineering design. At the same time, for wave energy conversion devices, since the waves in actual sea conditions change at any time, if fixed PTO system parameters are used, in weaker sea conditions, the wave force may not be enough to overcome the reaction force of the PTO system, resulting in failure to do work, and in stronger sea conditions, the work done by the wave force cannot be completely converted, resulting in a decrease in the efficiency of the wave energy conversion device. Traditional PTO drive devices are mostly hydraulic rods that extend and retract with the rise and fall of the float. Not only can the reaction force of the PTO system not be adjusted, but it is also inconvenient to repair because it is hinged or fixed on the energy-harvesting body. In addition, the current simulation programs that can be used for hydrodynamic characteristic calculations are difficult to consider the nonlinear effects of the mechanical PTO system, and traditional mechanical system analysis software cannot realize the consideration and evaluation of hydrodynamic loads.

[0003] In response to the above problems, this application takes the PTO drive device as the research object, designs a cam-driven PTO device installed on a fixed platform, and can change the reaction force of the PTO system in real time according to the wave conditions. A full-process coupling numerical model of the device and the hydrodynamic model is established to study its influence on the energy acquisition characteristics of the wave energy device. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and to provide a wave energy device based on a cam-driven PTO system and a simulation method thereof. By effectively connecting the cam-driven device in series with the wave energy device, a coupling numerical model is constructed, which can be used to guide the overall optimization development of the cam-driven PTO device and reasonably estimate the working performance.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A wave energy device based on a cam-driven PTO system comprises a cam driving device and a hydraulic energy storage system installed on a conductor frame platform, wherein the cam driving device and the hydraulic energy storage system are in contact with each other, and the cam driving device is connected to an oscillating float outside the conductor frame platform; and the hydraulic energy storage system is connected to a power generation system; The cam driving device comprises two parallel bases mounted on the catheter frame platform, two mutually meshing large gears and small gears are mounted between the two bases via a rotating shaft, the rotating shaft of the small gear extends out of the base and is fixedly mounted with a cam; the outer edge of the cam contacts the plunger of the hydraulic energy storage system; The oscillating float is fixedly mounted on the rotating shaft of the large gear.

[0006] The oscillating float comprises a float with a conical cross-section and a rocker arm fixed on the top of the float, and the other end of the rocker arm is fixed on the rotating shaft of the large gear.

[0007] The hydraulic energy storage system includes a plunger accumulator and a hydraulic motor. The plunger rod end of the plunger accumulator is against the outer edge of the cam. The plunger accumulator is connected to the hydraulic motor through a valve group and can drive the hydraulic motor to move. The hydraulic motor is connected to the power generation system. The plunger accumulator is an existing product, and the plunger accumulator driving the hydraulic motor is also an existing technology, which will not be described in detail.

[0008] The conductor frame platform comprises a top platform and four columns supporting the top platform.

[0009] The simulation method of the wave energy device based on the cam-driven PTO system includes: (1) Create a 3D geometric model based on the actual size of the rocker wave energy device and import the generated 3D geometric model into ANSYS-AQWA software as the basis for subsequent hydrodynamic analysis; perform pre-processing operations on the geometric model in the DesignModeler module of ANSYS; (2) Detailed settings of the mass properties of the wave energy power generation device were performed in the ANSYS-AQWA software to determine the total mass of the device and its distribution, and specific mass parameters were input into the geometric model to set coefficients related to hydrodynamics; (3) After completing the pre-processing of the geometric model, mesh the model based on the boundary element method; (4) Set the wave direction according to the actual sea conditions. On this basis, identify and determine the group of multi-body coupling objects, and set the wave frequency range and wave frequency difference parameters for frequency domain solution; (5) Perform frequency domain solution; (6) Setting up the limit restraint system between the wave energy power generation device and the offshore platform foundation; (7) In the time domain analysis, multiple dynamic parameters are set in detail to simulate the movement and response of the device in the time domain. Before the formal solution, a pre-solution is performed to verify the rationality of the settings, and the parameters are fine-tuned according to the pre-solution results to ensure the reliability and accuracy of the final simulation results. (8) Compile the mathematical model of the coupled motion of the plunger and the cam using the FORTRAN language and establish a dynamic link library that can complete real-time data exchange; (9) Place the dynamic link library in the core master subdirectory of the hydrodynamic solver ANSYS-AQWA and turn on the user-force user-defined switch; (10) Multiple key parameters of the PTO device can be adjusted and optimized in the dynamic link library; (11) After completing all settings and optimizations, perform the final calculation and solution.

[0010] In the step (1), in the DesignModeler module of ANSYS, necessary pre-processing operations are performed on the geometric model, including creating sections and cutting waterlines, so as to facilitate more accurate meshing and solving.

[0011] In the step (2), the mass parameters include the center of gravity position and the moment of inertia; and the coefficients related to hydrodynamics include the additional mass and the damping coefficient.

[0012] In the step (3), the grid division is only for the wading unit, and the wind turbine is not affected by the hydrodynamic load and is not included in the calculation; the number of grids in the grid division is less than or equal to 40,000, and the size of the grid limits the upper limit of the wave frequency selected in the frequency domain solution.

[0013] In the step (4), identifying and determining the group of multi-body coupling objects includes the coupling relationship between the device itself and its supporting structure, the floating body and other moving parts.

[0014] In the step (5), when the frequency domain calculation is completed, the ANALYSIS.HYD file and the ANALYSIS.AH1 file are generated, and the ANALYSIS.HYD file and the ANALYSIS.AH1 file contain hydrodynamic data, and the hydrodynamic data include additional mass, hydrostatic stiffness, radiation damping and excitation force; In step (7), the setting of dynamic parameters includes the wave height, wavelength, wave frequency and tidal properties of the incident wave, the setting of the initial position, the locking of the degrees of freedom, the selection of the time step and the planning of the overall simulation time.

[0015] In the step (10), the key parameters include the number of raised segments of the cam, the radius of curvature of the raised segments, the corresponding angle of the raised segments, the damping coefficient, the base circle radius, the number of plungers and the installation angle.

[0016] In the step (11), ANSYS-AQWA will calculate the motion response and energy capture efficiency of the wave energy power generation device under different wave conditions based on the set model and parameters; after the solution is completed, the result data will be exported to a CSV format file; these data include the hydrodynamic response, force conditions, and key indicators of energy capture efficiency of the device, which are used for further analysis and optimization.

[0017] In the step (11), the result data obtained include the movement speed and displacement of the wave energy power generation device in the heave direction, the wave surface elevation, and the shaft speed.

[0018] The beneficial effects of the present invention are as follows: the present invention solves the key problem that the traditional hydrodynamic calculation software cannot calculate and simulate mechanical structures such as cam-driven hydraulic PTO by effectively connecting the cam drive device and the wave energy device in series, and overcomes the difficulty that the traditional multi-body dynamics (MBD) software cannot handle hydrodynamic calculations. The performance evaluation of the wave energy device equipped with a mechanical PTO system is realized, which can be used to guide the overall optimization development of the PTO device based on cam drive and reasonably estimate the working performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of an embodiment of the present invention; Figure 2 is a force analysis diagram of a plunger rod and a cam according to an embodiment of the present invention; Figure 3 is a schematic diagram of a cam mathematical model according to an embodiment of the present invention; Figure 4 is a simulation flow chart of an embodiment of the present invention; Figure 5 It is a speed comparison diagram of Adams and mathematical model in a simulation system of an embodiment of the present invention; Figure 6 It is a displacement comparison diagram of Adams and mathematical model in a simulation system of an embodiment of the present invention; Figure 7 It is a torque comparison diagram of Adams and mathematical model in a simulation system of an embodiment of the present invention; Figure 8 , Fig. 9 , Fig.10 Three cams of different shapes according to an embodiment of the present invention; Fig.11 This is a comparison diagram of energy acquisition of three cams of different shapes according to an embodiment of the present invention; Among them, 101. float, 102. rocker arm, 103. rotating shaft, 200. column, 202. catheter frame platform, 302. large gear, 303. small gear, 304. cam, 305. plunger rod, 306. plunger cylinder, 307. hydraulic system. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0021] 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.

[0022] like Figure 1 As shown, the wave energy device based on the cam-driven PTO system includes a cam driving device and a hydraulic energy storage system installed on the conductor frame platform 202. The cam driving device and the hydraulic energy storage system are in contact with each other. The cam driving device is connected to an oscillating float outside the conductor frame platform 2. The oscillating float performs vertical swinging motion with the conductor frame platform 202 as support, driving the plunger rod 305 of the cam driving device to move, thereby performing hydraulic power generation.

[0023] The hydraulic energy storage system is connected to the power generation system. The wheel drive device includes two parallel bases installed on the jacket platform 2, and two mutually meshing large gears 302 and small gears 303 are installed between the two bases through the rotating shaft 103. The speed increasing system of the large and small gear planetary structure is adopted. After the power provided by the wave energy capture device is input into the planetary gear speed increasing system, the planetary speed increasing part 3 rotates under the action of the power, and the planetary speed increasing part converts the high torque of the power into a larger rotation angle.

[0024] The rotating shaft of the pinion 303 extends out of the base and is fixedly mounted with a cam 304; the outer edge of the cam 304 contacts the plunger rod 305 of the hydraulic energy storage system. The pinion 303 and the cam 304 operate synchronously to achieve the function of speed increase. The planetary gear drives the cam, and the hydraulic energy storage and transmission system including the plunger cylinder 306, energy storage assembly, valve group, and hydraulic motor are converted into electrical energy through the generator set. The oscillating float is fixedly mounted on the rotating shaft 103 of the large gear 302.

[0025] The cam 304 can realize various complex motion requirements. It has a simple, compact structure and convenient design. As long as the appropriate cam 304 profile is made, the plunger rod 305 can obtain a predetermined motion law. When the wave height is small and the float heave displacement is small, the cam 304 connected to the rocker arm 102 rotates at a small angle, the plunger mostly moves in a small push section, the plunger cylinder telescopic length is short, and the hydraulic reaction force generated is small, thereby preventing the float from being unable to start due to excessive hydraulic torque. On the contrary, when the sea conditions are bad and the cam 304 rotates at a large angle, the plunger rod 305 starts to move in a large push section, the plunger cylinder 306 telescopic length increases, and the hydraulic reaction force increases, thereby achieving the effect of improving the energy acquisition efficiency of the wave energy device.

[0026] The oscillating float includes a float 101 with a conical cross-section and a rocker arm 102 fixed to the top of the float. The other end of the rocker arm 102 is welded and fixed to the rotating shaft 103 of the large gear 302, which can remain stable so that the rocker arm 102 can rotate a certain angle with the up and down oscillation of the connected wave energy capture device, thereby generating a certain torque, and can drive the gear to rotate to drive the plunger rod 305 to generate electricity.

[0027] The hydraulic energy storage system includes a plunger accumulator and a hydraulic motor. The end of the plunger rod 305 of the plunger accumulator is against the outer edge of the cam 304. The plunger accumulator is connected to the hydraulic motor through a valve group and can drive the hydraulic motor to move. The hydraulic motor is connected to the power generation system. The plunger rod 305 is installed in the plunger cylinder 306. The plunger accumulator is an existing product, and the plunger accumulator driving the hydraulic motor is also an existing technology, which will not be repeated.

[0028] The jacket platform 202 includes a top platform and four columns 200 supporting the top platform.

[0029] like Figure 2-Figure 4 As shown, the simulation method of the wave energy device based on the cam-driven PTO system is as follows: Simulation steps: [1] Based on the actual size of the rocker wave energy device, a detailed 3D geometric model was created using professional 3D modeling software, and the generated 3D model was imported into ANSYS-AQWA software as the basis for subsequent hydrodynamic analysis. In the DesignModeler module of ANSYS, necessary pre-processing operations were performed on the geometric model, including creating sections, cutting waterlines, etc., to facilitate more accurate meshing and solving; [2] The mass properties of the wave energy power generation device are set in detail in the ANSYS-AQWA software to determine the total mass of the device and its distribution. Specific mass parameters are input into the model, including the center of gravity position and moment of inertia, and coefficients related to hydrodynamics, such as additional mass and damping coefficient, are set. [3] After completing the pre-processing of the geometric model, the model is meshed based on the boundary element method. The density and distribution of the mesh are reasonably selected according to the complexity of the device and the characteristics of the wave environment to ensure that the calculation efficiency is improved as much as possible while maintaining the calculation accuracy. The grid division is only for the wading units, and the wind turbines are not affected by the hydrodynamic load and are not included in the calculation; the number of grids in the grid division is less than or equal to 40,000, and the size of the grid limits the upper limit of the wave frequency selected in the frequency domain solution; [4] Set the wave direction according to the actual sea conditions, and on this basis, identify and determine the group of multi-body coupling objects, including the coupling relationship between the device itself and its supporting structure, floating body and other moving parts. Set the wave frequency range and wave frequency difference parameters for frequency domain solution to ensure that the simulation can cover the response characteristics of the device at different wave frequencies and provide comprehensive frequency domain analysis results; [5] The frequency domain solution is performed; the governing equations for the geometric model calculation are the linear potential flow theory and the Morrison equation. The loads borne by the floating body moving in the waves can be solved by the incident potential, diffraction potential and radiation potential. The viscosity of the liquid is considered in the frequency domain solution calculation, where the hydrodynamic load is the sum of the inertial load due to acceleration and the friction load due to the viscous effect; When the frequency domain calculation is finished, the ANALYSIS.HYD file and the ANALYSIS.AH1 file are generated. The ANALYSIS.HYD file and the ANALYSIS.AH1 file contain the hydrodynamic data, which include the added mass, hydrostatic stiffness, radiation damping and excitation force. [6] Setting up a limit restraint system between the wave energy power generation device and the offshore platform foundation; [7] In the time domain analysis, multiple dynamic parameters are set in detail to simulate the movement and response of the device in the time domain. These settings include the wave height, wavelength, wave frequency and tidal properties of the incident wave, the setting of the initial position, the locking of the degrees of freedom, the selection of the time step and the planning of the overall simulation time. Before the formal solution, a pre-solution is performed to verify the rationality of the settings, and the parameters are fine-tuned according to the pre-solution results to ensure the reliability and accuracy of the final simulation results; [8] The coupled motion mathematical model of the plunger and cam is constructed through force analysis and motion analysis. It is compiled using FORTRAN language to generate a dynamic link library that can interact with the ANSYS-AQWA simulation environment in real time. The coupled motion of the plunger and cam is accurately modeled. The force analysis, motion analysis and mathematical model are shown below.

[0030] Force analysis: Figure 2 and Figure 3 As shown in the figure, the plunger rod is taken as the research object, which is subjected to the reaction force Fa of the plunger cylinder and the thrust of the cam mechanism. F n , the two produce a combined force F Used to push the plunger rod, the hydraulic pressure on the plunger rod is simplified into a linear damping force of the damping coefficient multiplied by the plunger rod speed, so: F= C*v in: C ——linear damping coefficient; v ——Plunger rod movement speed; The resistance of the cam to the plunger rod during its rotation is F n ' , F n ' = F n， The tangential force generated F b for: , in, θ is the angle between the cam force direction and the plunger, and the torque converted to the platform hinge point is: , in: i ——gear ratio; L ——The distance between the cam rotation center and the plunger rod action position.

[0031] Motion Analysis: From the geometric conditions, it can be obtained that when the plunger moves in the EQ section, ,

[0032] When the plunger moves in the GQ section: , in: s——movement displacement of plunger rod; r r—— Base circle radius of the cam; r'—— Radius of the plunger ball; δ1—— Rotation angle of the cam; ω—— Rotation speed of the cam; l KG —— Distance between point K and point G on the cam; l ok —— Distance between the center of the cam and the center K of the QG arc segment. Cams with different shapes have different l ok ; δ 01 —— Lift angle of the cam. Cams with different shapes have different δ 01 ; Q, G—— Connection points of the cam arc segment and the straight line segment; E—— Tangent point of the inscribed circle of the cam and the inner edge of the cam.

[0033] When ω > 0 and 0 < δ1 < A1, , When A1 < δ1 < P1, , When 2P1 < δ1 < A2, , When A2 < δ1 < 180°, , When ω < 0 and A3 < δ1 < 2P1, , When P1 < δ1 < A3, , When -A1 < δ1 < 0, , When -P1 < δ1 < -A1, , When -A2 < δ1 < -2P1, , When 180° < δ1 < -A2, , When ω > 0 and -2P1 < δ1 < -A3, , When -A3 < δ1 < -P1 , Among them, A1, A2, A3, and P1 represent the angles at which the cam rotates to the connection points of each arc segment and the straight line segment; [9] Place the dynamic link library in the core main control subdirectory of the hydrodynamic solver ANSYS-AQWA and turn on the user-force user-defined switch;

[10] In the dynamic link library, multiple key parameters of the PTO device can be adjusted and optimized. These parameters include the number of cam segments, the radius of curvature of the cam segments, the corresponding angle of the cam segments, the damping coefficient, the base circle radius, the number of plungers and the installation angle. By adjusting these parameters, the cam shape and the installation method of the plunger can be optimized, thereby improving the energy capture efficiency and operating stability of the PTO system. The parameter adjustment process is usually accompanied by multiple simulations and result analysis to ensure that the final design exhibits excellent performance under various working conditions;

[11] After completing all settings and optimizations, the final calculation is performed. ANSYS-AQWA will calculate the motion response and energy capture efficiency of the wave energy generation device under different wave conditions based on the set model and parameters. After the solution is completed, the result data is exported to a CSV format file. These data include key indicators such as the hydrodynamic response, force conditions, and energy capture efficiency of the device, which are used for further analysis and optimization; The result data obtained include the movement speed and displacement of the wave energy power generation device in the heave direction, wave surface elevation, shaft speed, etc.

[0034] In order to verify the reliability and accuracy of the results of this research method, a cam drive device was established in the professional mechanical power software Adams, and the Adams simulation results were compared with the results of the numerical simulation method introduced in the present invention.

[0035] Figure 5-Figure 7 The figure is a comparison of the displacement, velocity and torque of the plunger derived from the numerical simulation method introduced in the present invention and Adams. It can be seen that the results of the full-process coupling simulation method introduced in the present invention are in good agreement with the simulation calculation results of the professional mechanical power software Adams. It can be considered that the numerical model constructed by the method of the present invention can simulate the movement and force of the cam drive device more realistically, and can make an accurate prediction of the full-process working performance of the device.

[0036] like Figure 8-Figure 10 The energy gain comparison of the different cam shapes shown (cam type A, cam type B, cam type C) is as follows: like Fig.11As shown in the figure, the average power comparison of the three shapes of cams at a water depth of 40m, a wave height of 0.7m, and periods of 3.5, 4, 4.5, 5, 5.5, and 6s proves that optimizing the cam shape can significantly improve the energy acquisition efficiency of the float.

[0037] 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 wave energy device based on a cam-driven PTO system, characterized in that: It includes a cam drive device and a hydraulic energy storage system installed on the jacket platform, the cam drive device and the hydraulic energy storage system are in contact, the cam drive device is connected to an oscillating float outside the jacket platform; the hydraulic energy storage system is connected to a power generation system; The cam driving device comprises two parallel bases mounted on the catheter frame platform, two mutually meshing large gears and small gears are mounted between the two bases via a rotating shaft, the rotating shaft of the small gear extends out of the base and is fixedly mounted with a cam; the outer edge of the cam contacts the plunger of the hydraulic energy storage system; The oscillating float is fixedly mounted on the rotating shaft of the large gear.

2. The wave energy device based on the cam-driven PTO system as claimed in claim 1, characterized in that: The oscillating float comprises a float with a conical cross-section and a rocker arm fixed on the top of the float, and the other end of the rocker arm is fixed on the rotating shaft of the large gear.

3. The wave energy device based on the cam-driven PTO system as claimed in claim 1, characterized in that: The hydraulic energy storage system includes a plunger accumulator and a hydraulic motor. The end of the plunger rod of the plunger accumulator is against the outer edge of the cam. The plunger accumulator is connected to the hydraulic motor through a valve group and can drive the hydraulic motor to move. The hydraulic motor is connected to the power generation system.

4. The wave energy device based on the cam-driven PTO system as claimed in claim 1, characterized in that: The conductor frame platform comprises a top platform and four columns supporting the top platform.

5. A method for simulating a wave energy device based on a cam-driven PTO system as claimed in claim 1, characterized in that: include: (1) Create a 3D geometric model based on the actual size of the rocker wave energy device and import the generated 3D geometric model into ANSYS-AQWA software as the basis for subsequent hydrodynamic analysis; perform pre-processing operations on the geometric model in the DesignModeler module of ANSYS; (2) Detailed settings of the mass properties of the wave energy power generation device were performed in the ANSYS-AQWA software to determine the total mass of the device and its distribution, and specific mass parameters were input into the geometric model to set coefficients related to hydrodynamics; (3) After completing the pre-processing of the geometric model, mesh the model based on the boundary element method; (4) Set the wave direction according to the actual sea conditions. On this basis, identify and determine the group of multi-body coupling objects, and set the wave frequency range and wave frequency difference parameters for frequency domain solution; (5) Perform frequency domain solution; (6) Setting up the limit restraint system between the wave energy power generation device and the offshore platform foundation; (7) In the time domain analysis, multiple dynamic parameters are set in detail to simulate the movement and response of the device in the time domain. Before the formal solution, a pre-solution is performed to verify the rationality of the settings, and the parameters are fine-tuned according to the pre-solution results to ensure the reliability and accuracy of the final simulation results. (8) Compile the mathematical model of the coupled motion of the plunger and the cam using the FORTRAN language and establish a dynamic link library that can complete real-time data exchange; (9) Place the dynamic link library in the core master subdirectory of the hydrodynamic solver ANSYS-AQWA and turn on the user-force user-defined switch; (10) Multiple key parameters of the PTO device can be adjusted and optimized in the dynamic link library; (11) After completing all settings and optimizations, perform the final calculation and solution.

6. The simulation method of the wave energy device based on the cam-driven PTO system as claimed in claim 5, characterized in that: In the step (1), in the DesignModeler module of ANSYS, necessary pre-processing operations are performed on the geometric model, including creating sections and cutting waterlines, so as to facilitate more accurate meshing and solving; In the step (2), the mass parameters include the center of gravity position and the moment of inertia; and the coefficients related to hydrodynamics include the additional mass and the damping coefficient.

7. The simulation method of the wave energy device based on the cam-driven PTO system as claimed in claim 5, characterized in that: In the step (3), the grid division is only for the wading unit, and the wind turbine is not affected by the hydrodynamic load and is not included in the calculation; the number of grids in the grid division is less than or equal to 40,000, and the size of the grid limits the upper limit of the wave frequency selected in the frequency domain solution; In the step (4), identifying and determining the group of multi-body coupling objects includes the coupling relationship between the device itself and its supporting structure, the floating body and other moving parts.

8. The simulation method of the wave energy device based on the cam-driven PTO system as claimed in claim 5, characterized in that: In the step (5), when the frequency domain calculation is completed, the ANALYSIS.HYD file and the ANALYSIS.AH1 file are generated, and the ANALYSIS.HYD file and the ANALYSIS.AH1 file contain hydrodynamic data, and the hydrodynamic data include added mass, hydrostatic stiffness, radiation damping and excitation force.

9. The simulation method of the wave energy device based on the cam-driven PTO system as claimed in claim 5, characterized in that: In step (7), the setting of dynamic parameters includes the wave height, wavelength, wave frequency and tidal current properties of the incident wave, the setting of the initial position, the locking of the degrees of freedom, the selection of the time step and the planning of the overall simulation time; In the step (10), the key parameters include the number of raised segments of the cam, the radius of curvature of the raised segments, the corresponding angle of the raised segments, the damping coefficient, the base circle radius, the number of plungers and the installation angle.

10. The simulation method of the wave energy device based on the cam-driven PTO system as claimed in claim 5, characterized in that: In the step (11), ANSYS-AQWA will calculate the motion response and energy capture efficiency of the wave energy power generation device under different wave conditions according to the set model and parameters; after the solution is completed, the result data will be exported to a CSV format file; these data include the hydrodynamic response, force conditions, and key indicators of energy capture efficiency of the device, which are used for further analysis and optimization; the obtained result data include the motion speed and displacement of the wave energy power generation device in the heave direction, the wave surface elevation, and the shaft speed.

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