Direct-driven wave power generation dry-type simulation device

Abstract

The invention discloses a direct-drive wave power generation dry-type simulation device, and belongs to the technical field of wave power generation. Comprising a base, an electric cylinder, a linear generator and a flexible coupling connection module. The flexible coupling connection module is connected between the power output end of the electric cylinder and the linear generator rotor and comprises at least one set of springs. According to the invention, power output with adjustable amplitude and frequency is provided through the electric cylinder, and a dynamic model of the platform is equivalent to a dynamic model of a floater in real waves by adjusting system parameters, so that the running state of a direct-driven wave energy power generation device under an ocean wave condition can be accurately simulated, and a power capture optimization control algorithm is effectively verified. The problems that a traditional test platform is insufficient in motion simulation precision, control algorithm verification fails, and the wave condition simulation range is limited are solved.

Description

Technical Field

[0002] This invention relates to the field of wave energy power generation technology, and in particular to a direct-drive dry simulation device for wave energy power generation. Background Technology

[0003] Against the backdrop of rapid global population growth and continued industrialization, energy demand continues to rise. Long-term reliance on the development and use of fossil fuels has led to a series of severe environmental problems, including air pollution, the greenhouse effect, and climate change. Promoting the development and utilization of clean and renewable energy is of great significance for building a resource-saving and environmentally friendly society. Among numerous renewable energy sources, wave energy has become a focus of current research due to its wide distribution, high energy density, and strong sustainability. Compared with wind and solar energy, wave energy not only has higher energy density but also provides more stable and continuous power output, and is expected to become an important component of the future energy system.

[0004] Devices that capture wave energy and convert it into usable energy are called wave energy converters (WECs). Depending on the energy transfer method, wave energy power generation devices can be categorized into direct-drive, hydraulic, mechanical, and pneumatic types. Among these, direct-drive wave energy power generation devices stand out due to their high-efficiency energy conversion characteristics. This device can directly capture wave energy using the heave motion of a float, eliminating the need for complex intermediate transmission mechanisms. It only requires a two-stage conversion from wave energy to mechanical energy to electrical energy, significantly reducing energy loss and showing broad development prospects.

[0005] However, experimental verification of direct-drive wave energy generation technology usually relies on wave-making tanks, which suffer from problems such as large space requirements and high costs, limiting the efficient conduct of related research. Therefore, it is particularly necessary to develop a dry test platform suitable for direct-drive wave energy generation devices to simulate the operating conditions of wave energy generation devices under wave excitation, so as to accelerate the research and optimization of wave energy generation technology.

[0006] Currently, the dry test platform for direct-drive wave energy generation devices still has the following shortcomings and defects: 1) Most existing dry test platforms suitable for direct-drive wave energy generation devices adopt crank-slider mechanisms. However, the crank-slider mechanism has limited stiffness and load-bearing capacity of the crank and connecting rod when under load. Furthermore, when the crank rotates at a constant speed, the displacement of the slider is not a strict sine function, which cannot perfectly simulate the sinusoidal excitation force under regular wave conditions.

[0007] 2) Most existing dry test platforms rigidly connect the drive mechanism to the linear generator mover (e.g., rigidly connecting the slider of a crank-slider mechanism to the linear generator mover). This can only simulate the motion of the wave power generation device under regular wave conditions, but cannot simulate the sinusoidal excitation force experienced by the wave power generation device. The purpose of developing dry test platforms is often to verify PTO force-related control algorithms, that is, to change the motion state of the wave power generation device by controlling the magnitude of the anti-electromagnetic force of the linear motor during power generation to capture more energy. However, in the above-mentioned cases, the motion of the drive mechanism is often fixed, and no matter how the anti-electromagnetic force of the motor is controlled, the motion state of the mover cannot be changed, let alone the effectiveness of the relevant control algorithm.

[0008] 3) Most dry test platforms currently use mechanisms that can achieve sinusoidal motion characteristics at the end. Since the mechanism parameters are often fixed, the motion at the end of the mechanism is also fixed. However, the period and amplitude of real waves are different. Therefore, dry test platforms based on mechanisms with sinusoidal motion characteristics at the end often cannot meet the test requirements for simulating different wave conditions. Summary of the Invention

[0009] The purpose of this invention is to provide a direct-drive dry simulation device for wave energy generation, which solves the problems of insufficient motion simulation accuracy, failure of control algorithm verification, and limited range of wave condition simulation.

[0010] To achieve the above objectives, the present invention provides a direct-drive dry simulation device for wave energy generation, comprising: Base; An electric cylinder, which is fixed to the base by an electric cylinder support, is used to generate power output with adjustable amplitude and frequency; A linear generator, the stator of which is fixed to the base via a base plate; A flexible coupling connection module is connected between the power output end of the electric cylinder and the mover of the linear generator. It is used to transmit the power of the electric cylinder to the mover of the linear generator, and to make the motion state of the mover of the linear generator simultaneously subject to the output force of the electric cylinder and the anti-electromagnetic force of the linear generator. The flexible coupling connection module includes at least one set of springs.

[0011] Preferably, the flexible coupling connection module includes: An electric cylinder thrust plate, which is fixedly connected to the power output end of the electric cylinder; A linear generator mover connector, which is fixedly connected to the mover of the linear generator; The first spring assembly has a stiffness value of K 1 It is connected between the electric cylinder thrust plate and the linear generator mover connector; The second spring assembly has a stiffness value of K 2 It is connected between the linear generator rotor connector and a guide rail support fixed on the base.

[0012] Preferably, both the first spring group and the second spring group are compression springs.

[0013] Preferably, it also includes a guiding mechanism, which includes a guide shaft fixed on the base, and the electric cylinder thrust plate and the linear generator actuator connector are sleeved on the guide shaft through linear bearings.

[0014] Preferably, it further includes a damping adjustment device, which comprises a countersunk screw screw screwable into the guide rail support, the end of the countersunk screw being able to abut against the guide shaft to provide adjustable sliding friction damping. .

[0015] Preferably, the electric cylinder includes an electric cylinder motor, a ball screw component driven by the electric cylinder motor, and an electric cylinder mover as a power output end. The electric cylinder motor receives pulse signals to drive and control the electric cylinder mover to perform sinusoidal motion according to a preset amplitude and frequency.

[0016] This invention also provides a method for simulating the buoy dynamics of a direct-drive wave energy generation dry simulation device, comprising the following parameter matching steps: S1. By adjusting the total mass of the linear generator mover and its connecting parts. m With the total mass of the equivalent float system ; S2. Adjust the stiffness of the first spring assembly. K 1 Stiffness of the second spring assembly K 2 sum ( K 1 +K 2 ), with the equivalent still water stiffness of a buoy S m ; S3. By adjusting the friction damping in the dry test platform Radiation damping of an equivalent float R m ; S4. Adjust the output displacement amplitude of the electric cylinder. A Stiffness of the first spring assembly K 1 product K 1 · A With equivalent wave excitation force The amplitude; S5. By adjusting the output frequency of the electric cylinder With equivalent wave excitation frequency .

[0017] Preferably, the friction damping The damping adjustment is steplessly adjusted by a damping adjustment device, which is a countersunk screw that can be screwed into the support and pressed against the guide shaft.

[0018] This invention also provides a control verification method for a direct-drive wave energy power generation dry simulation device, comprising: By controlling the operation of the electric cylinder, varying wave excitation conditions are simulated; By controlling the linear generator to apply a varying anti-electromagnetic force F pto To simulate different power capture control strategies; The effectiveness of the control strategy under simulated wave excitation was verified by collecting the motion state parameters and power generation parameters of the linear generator mover.

[0019] Preferably, the control strategy includes damping control or complex conjugate control, and the wave excitation condition includes regular waves or irregular waves.

[0020] Therefore, the direct-drive dry simulation device for wave energy generation of the present invention, which adopts the above-described structure, has the following beneficial effects: (1) This invention proposes a dry test platform suitable for direct-drive wave energy power generation devices. It adopts a flexible coupling structure of electric cylinder and spring, so that the motion of the linear generator mover is affected by both the electric cylinder drive and the anti-electromagnetic force of the linear motor, and truly realizes the full dynamic simulation of "wave excitation - float motion - anti-electromagnetic force action", thereby solving the core defect of traditional test platforms that are "fixed motion and ineffective control".

[0021] (2) The electric cylinder described in this invention is an active driver that is independent of the anti-electromagnetic force control of the linear generator. It realizes the dynamic decoupling of wave excitation and PTO control, thereby enabling the verification of power capture optimization control algorithms such as damping control and complex conjugate control.

[0022] (3) The dry test platform described in this invention has a simple structure, with the main structure consisting only of an electric cylinder, a spring, and a linear generator. It has no complex transmission structure, and the forces on the structure are all on a straight line, resulting in strong load-bearing capacity and high reliability. It eliminates the high costs of building and maintaining water tanks, and reduces the experimental space from tens of meters to a few meters, significantly reducing R&D costs and improving experimental efficiency.

[0023] (4) The dry test platform described in this invention can highly simulate the dynamic characteristics of real waves. The electric cylinder can precisely adjust the excitation displacement through pulse signals, flexibly matching wave excitation with different wave heights and frequencies. The spring stiffness can be adjusted... K 1 、K 2 Friction damping Total mass of the mover and its connecting parts m The hydrostatic stiffness of the equivalent float S m Radiation damping R m and total mass This equivalent matching allows laboratory data to accurately reflect the device's response in a marine environment.

[0024] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a direct-drive wave energy generation dry simulation device according to the present invention; Figure 2 This is a schematic diagram of a direct-drive wave energy generation device according to the present invention, which is a dry simulation device for direct-drive wave energy generation. Figure Labels 1-Electric cylinder thrust plate, 2-Compression spring, 3-Guide rail support, 4-Linear generator mover connector, 5-Linear generator mover, 6-Linear generator stator, 7-Base plate, 8-Counterhead screw, 9-Electric cylinder support, 10-Guide shaft, 11-Electric cylinder ball screw assembly, 12-Electric cylinder motor, 13-Base, 14-Guide shaft support, 15-Electric cylinder mover, 16-Linear bearing, 17-Electric cylinder thrust head. Detailed Implementation

[0026] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0028] Example like Figure 1 As shown, the present invention provides a direct-drive wave energy power generation dry simulation device, which mainly includes an electric cylinder, a linear generator, a flexible coupling connection module, and other structures.

[0029] The electric cylinder of this invention consists of an electric cylinder motor 12, an electric cylinder ball screw 11, and an electric cylinder mover 15. By rationally designing the electric cylinder pulse signal and using the pulse mode of the electric cylinder driver, the electric cylinder mover 15 can be driven to perform sinusoidal motion, and the amplitude and period of the sinusoidal motion can be changed. The generator is a flat-plate linear generator, consisting of a linear generator mover 5 and a linear generator stator 6. The flexible coupling connection module includes an electric cylinder thrust plate 1, a compression spring 2, a guide rail support 3, and a linear generator mover connector 4.

[0030] The guide rail support 3 and the electric cylinder support 9 are threadedly installed on the base 13. The base plate 7 is connected to the linear motor through the threaded hole at the bottom of the linear motor stator 6, and then threadedly installed on the base 13. Four guide shaft supports 14 are installed in the reserved holes of the guide rail support 3 and the electric cylinder support 9. Two guide shafts pass through the inner holes of the guide shaft supports 14 and are positioned. The electric cylinder thrust head 17 is connected to the electric cylinder mover 15 through the external thread, and is fixedly connected to the electric cylinder thrust plate 1 through the thread. The linear generator mover connector 4 is threadedly fastened to the linear generator mover 5. The electric cylinder thrust plate 1 and the linear generator mover connector 4 are both fitted onto the guide shaft 10 after the linear bearing 16 is installed. The electric cylinder thrust plate 1 and the linear generator mover connector 4 are connected by a set of stiffness... K 1 The compression springs (first spring group) are connected together, and the linear generator mover connector 4 and the guide rail support 3 are connected by a set of springs with stiffness of 4. K 2 The compression springs (second spring group) are connected together, and both spring groups are sleeved on the guide shaft 10.

[0031] The countersunk screw 8 abuts against the guide shaft. By rotating the countersunk screw, the sliding friction damping of the linear generator power connector on the guide shaft 10 can be changed. C f .

[0032] Working principle The structure of a direct-drive wave power generation device is as follows: Figure 2 As shown, a float drifts on the water surface, while the stator of a linear generator is fixed to the bottom. The mover is connected to the float via a connecting rod. When the float moves with the waves, it drives the mover of the linear generator, causing relative motion between the mover and the stator, thus generating electrical energy. During this power generation process, the float's motion can be altered by controlling the counter-electromagnetic force of the linear generator to capture more energy.

[0033] In the above structure, the float has only one degree of freedom in the heave direction; the mooring force, structural friction, and viscous forces are neglected. The differential equation of the float's motion is obtained according to Newton's second law: (1); In the equation, the force on the left side of the equal sign represents the inertial force of the float; M This refers to the total mass of the float, linear generator mover, and other auxiliary components. z v The displacement is the displacement due to the heave motion; the right side of the equation includes the hydrostatic restoring force on the float. F b Radiation F r Wave excitation force F ex and the reaction force of the energy harvesting device F pto In this invention, the PTO force is the anti-electromagnetic force generated by the linear generator.

[0034] The excitation force can be expressed as the product of the excitation force coefficient and the wave surface function: (2); The radiation force is linearly related to the buoy velocity, and can be expressed as the radiation damping coefficient. R m Product of the float's velocity: (3); The restoring force in still water is linearly related to the displacement of the float, and the ratio between the two is called the still water stiffness. S m Its size is determined by the cross-sectional area of ​​the float. S Decide: (4); Expanding the various hydrodynamic forces yields the differential equations for the buoy's dynamics: (5); The dynamic model of the direct-drive wave energy generation device dry test platform proposed in this invention is as follows: (6); in, This refers to the displacement of the moving part of the electric cylinder. This refers to the displacement of the moving part of the linear generator. m This refers to the total mass of the linear generator's rotor and its connecting parts.

[0035] By controlling the electric cylinder, the moving part of the electric cylinder can be made to perform a sinusoidal motion. (7); Substituting equation (7) into equation (6) and rearranging, we get (8); Comparing equations (5) and (8), it can be found that the dynamic model of the dry test platform described in this invention is completely consistent with the dynamic model of the actual direct-drive wave power generation device in form. The total mass of the linear generator mover and its connecting parts can be adjusted by adding or removing counterweights. m With equivalent total float mass The sliding friction damping is changed by rotating the countersunk screw. With equivalent radiation damping coefficient R m By changing the stiffness of the two sets of springs and ( K 1 +K 2 With equivalent hydrostatic stiffness S m By changing the displacement of the electric cylinder mover Amplitude and spring stiffness K 1 With equivalent wave excitation force amplitude By changing the displacement frequency of the electric cylinder mover With equivalent wave excitation frequency .

[0036] In principle, the dry test platform described in this invention is completely equivalent to an actual wave power generation device, and can directly conduct experiments on power capture optimization control algorithms such as damping control and complex conjugate control.

[0037] Therefore, this invention can drive the electric cylinder mover to perform sinusoidal motion with adjustable amplitude and frequency by precisely controlling the pulse signal, and drive the linear generator to move by transmitting power through a double-layer spring group. This structure not only gives the whole system adjustable parameters and decoupled force and motion dynamic characteristics, but also makes the structure simple, reliable and strong in load-bearing capacity.

[0038] Furthermore, the buoy dynamics equivalence method provided by this invention ensures that the platform dynamics equations completely correspond to the actual buoy dynamics equations. The specific implementation method includes: adjusting the mass of the mover and connecting parts. m With equivalent total mass Adjusting the spring stiffness K1+K2 Matching float static stiffness S m Adjusting friction damping Simulated radiation damping R m Adjust the excitation amplitude of the electric cylinder A With spring stiffness K1 product( K1·A Equivalent incentive amplitude Adjust the frequency of the electric cylinder Equivalent wave excitation frequency This dynamic equivalent method overcomes the limitation of traditional rigid mechanisms in simulating control effects, enabling dry platforms to accurately reproduce the dynamic behavior under real sea conditions.

[0039] The control method provided by this invention also supports power capture optimization algorithm experiments, such as damped control and complex conjugate control. Specifically, it includes: independently adjusting wave excitation (e.g., simulating irregular waves) with an electric cylinder, while a linear generator applies varying... The experiment utilizes two-degree-of-freedom control to verify the effectiveness of different strategies in improving energy capture efficiency. This control capability enables the experimental platform to not only verify fixed control algorithms under steady-state wave conditions but also to study optimal control responses under dynamic wave conditions, providing reliable experimental data for practical marine environment applications.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A direct-drive dry simulation device for wave energy generation, characterized in that, include: Base; An electric cylinder, which is fixed to the base by an electric cylinder support, is used to generate power output with adjustable amplitude and frequency; A linear generator, the stator of which is fixed to the base via a base plate; A flexible coupling connection module is connected between the power output end of the electric cylinder and the mover of the linear generator. It is used to transmit the power of the electric cylinder to the mover of the linear generator, and to make the motion state of the mover of the linear generator simultaneously subject to the output force of the electric cylinder and the anti-electromagnetic force of the linear generator. The flexible coupling connection module includes at least one set of springs.

2. The direct-drive wave energy generation dry simulation device according to claim 1, characterized in that, The flexible coupling connection module includes: An electric cylinder thrust plate, which is fixedly connected to the power output end of the electric cylinder; A linear generator mover connector, which is fixedly connected to the mover of the linear generator; The first spring assembly has a stiffness value of K 1 It is connected between the electric cylinder thrust plate and the linear generator mover connector; The second spring assembly has a stiffness value of K 2 It is connected between the linear generator rotor connector and a guide rail support fixed on the base.

3. The direct-drive wave energy generation dry simulation device according to claim 2, characterized in that, Both the first spring group and the second spring group are compression springs.

4. The direct-drive wave energy generation dry simulation device according to claim 3, characterized in that, It also includes a guiding mechanism, which includes a guide shaft fixed on the base, and the electric cylinder thrust plate and the linear generator actuator connector are sleeved on the guide shaft through linear bearings.

5. A direct-drive dry simulation device for wave energy generation according to claim 4, characterized in that, It also includes a damping adjustment device comprising a countersunk screw screw screwable into the guide rail support, the end of the countersunk screw being able to abut against the guide shaft to provide adjustable sliding friction damping. .

6. The direct-drive wave energy generation dry simulation device according to claim 1, characterized in that, The electric cylinder includes an electric cylinder motor, a ball screw component driven by the electric cylinder motor, and an electric cylinder mover as the power output end. The electric cylinder motor receives pulse signals to drive and control the electric cylinder mover to perform sinusoidal motion according to a preset amplitude and frequency.

7. A method for simulating the buoy dynamics of a direct-drive wave energy generation dry simulation device according to any one of claims 1-6, characterized in that, The following parameter matching steps are included: S1. By adjusting the total mass of the linear generator mover and its connecting parts. m With the total mass of the equivalent float system ; S2. Adjust the stiffness of the first spring assembly. K 1 Stiffness of the second spring assembly K 2 sum ( K 1 +K 2 ), with the equivalent still water stiffness of a buoy S m ; S3. By adjusting the friction damping in the dry test platform Radiation damping of an equivalent float R m ; S4. Adjust the output displacement amplitude of the electric cylinder. A Stiffness of the first spring assembly K 1 product K 1 · A With equivalent wave excitation force The amplitude; S5. By adjusting the output frequency of the electric cylinder With equivalent wave excitation frequency .

8. The buoy dynamics equivalent method according to claim 7, characterized in that, The friction damping The damping adjustment is steplessly adjusted by a damping adjustment device, which is a countersunk screw that can be screwed into the support and pressed against the guide shaft.

9. A control verification method for a direct-drive wave energy generation dry simulation device according to any one of claims 1-6, characterized in that, include: By controlling the operation of the electric cylinder, varying wave excitation conditions are simulated; By controlling the linear generator to apply a varying anti-electromagnetic force F pto To simulate different power capture control strategies; The effectiveness of the control strategy under simulated wave excitation was verified by collecting the motion state parameters and power generation parameters of the linear generator mover.

10. The control verification method according to claim 9, characterized in that, The control strategy includes damping control or complex conjugate control, and the wave excitation conditions include regular waves or irregular waves.

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