Floating photovoltaic dynamic response test device under extreme wind wave flow coupling effect

Abstract

The invention relates to a floating photovoltaic dynamic response test device under an extreme wind wave flow coupling effect. The floating photovoltaic dynamic response test device comprises an environment simulation system, a semi-submersible photovoltaic platform system, a mooring system and a data measurement and acquisition system, the environment simulation system simulates the coupling effect of wind, wave and flow composite loads. The semi-submersible photovoltaic platform system comprises a photovoltaic module model constructed according to a predetermined scale ratio and a floating body module for providing support and buoyancy for the photovoltaic module model, and can truly reflect the wind load effect of a photovoltaic structure and the hydrodynamic response of the platform. And in the data measurement and acquisition system, a dynamic visual sensor is matched with a pressure sensor, so that synchronous and accurate observation and measurement of six-degree-of-freedom motion of the platform, mooring tension, particularly a deck wave rising process and a slamming load are realized. According to the invention, the problem of the traditional test in the aspects of complex load simulation and deck wave fine observation under extreme sea conditions is solved, and a reliable test means is provided for the safety design and performance evaluation of a deep and far sea floating photovoltaic platform.

Description

Technical Field

[0001] This invention relates to floating photovoltaic dynamic response testing technology in marine engineering, and in particular to a floating photovoltaic dynamic response testing device under extreme wind, wave and current coupling effects. Background Technology

[0002] Floating photovoltaic (PV) systems are a new type of marine energy development equipment that floats on the sea surface to support PV modules and achieve solar photovoltaic conversion. They do not rely on land resources or seabed piles for fixation, making them widely adaptable to diverse marine scenarios such as nearshore sheltered waters and deep seas. Furthermore, they can be developed in synergy with other energy forms such as offshore wind power, providing a key technological path for expanding the boundaries of PV applications and improving the comprehensive utilization efficiency of marine energy. Floating PV systems are gradually developing into an important part of the clean energy industry and are playing an increasingly prominent role in the global energy transition.

[0003] Response analysis methods for floating photovoltaic (PV) platforms mainly include analytical methods, numerical simulations, and physical model tests. Their floating-mooring system exhibits significant dynamic responses under complex marine environmental loads, directly impacting the system's safety, stability, and power generation efficiency. Due to the complex structure of floating PV platforms, their dynamic responses under various loads involve multi-body coupling and fluid-structure interaction effects. Therefore, theoretical calculations regarding the response of floating PV platforms are relatively limited. Currently, the commonly used analytical methods are physical model tests and numerical simulations. As a floating structure at sea, floating PV platforms are significantly affected by environmental loads such as wind, waves, and currents. Numerical simulation methods inevitably simplify environmental effects; therefore, physical model tests have become the most intuitive and effective method for studying the dynamic response of floating PV platforms under combined loads.

[0004] As floating structures at sea, floating photovoltaic (PV) platforms are significantly affected by environmental loads such as wind, waves, and currents. Frequent typhoons in deep-sea areas pose challenges to the safety of floating PV systems due to extreme conditions caused by typhoons and other factors. Extreme wind, waves, and currents can lead to platform capsizing, mooring breakage, and damage to PV panels. To ensure the safety of floating PV power plants under different sea conditions, it is essential to thoroughly understand the platform's motion characteristics under extreme conditions. Due to their relatively small structural size, low overall stiffness, and large installation area, the stability of common floating PV platforms under the influence of wind, waves, and currents is difficult to guarantee, further increasing the difficulty of floating PV model testing. Therefore, it is necessary to find PV platforms more suitable for deep-sea environments.

[0005] In the face of frequent extreme conditions in deep-sea environments, deck waves pose a significant threat to platform stability. Effectively observing the dynamic evolution of deck waves under extreme sea conditions and analyzing the impact of slamming loads is crucial for platform safety. Traditional methods utilize high-speed photography to record wave morphology changes, but these are easily limited by strong glare, splashing waves, and laboratory lighting conditions, while also generating massive amounts of frame-by-frame image data, resulting in a heavy post-processing workload. Currently, there is a lack of deep-sea floating photovoltaic test devices capable of effectively simulating the effects of deck waves under extreme wind, wave, and current coupling.

[0006] It should be noted that the information disclosed in the background section above is only for understanding the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] The main objective of this invention is to overcome the deficiencies in the aforementioned background technology and provide a floating photovoltaic dynamic response test device under extreme wind, wave and current coupling.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: A floating photovoltaic dynamic response test device under extreme wind, wave and current coupling effects includes: An environmental simulation system is used to generate controllable wind, wave, and flow fields in a test pool to simulate the coupling effects of wind, wave, and flow loads. A semi-submersible photovoltaic platform system is arranged in the test pool to simulate the hydrodynamic response of a floating photovoltaic platform under the loads generated by the environmental simulation system. The semi-submersible photovoltaic platform system includes photovoltaic modules and a floating body assembly. The photovoltaic modules are constructed as a scaled-down model based on a floating photovoltaic platform prototype at a predetermined scale and are placed above the floating body assembly to bear wind loads and reflect the influence of the photovoltaic structure on the platform's movement. The floating body assembly is used to bear wave loads, current loads, and wind loads, and to provide support and buoyancy for the photovoltaic modules. The mooring system, with its two ends connected to the semi-submersible photovoltaic platform system and the bottom of the test pool respectively, provides restoring stiffness to the platform and constrains its movement; The data measurement and acquisition system uses various sensors deployed in the semi-submersible photovoltaic platform system and the test environment to collect data on the platform's six-degree-of-freedom motion response, mooring tension, deck wave load, and wave impact evolution under the coupled effects of wind, waves, and currents. The system includes a deck wave observation system for observing deck waves, comprising a dynamic visual sensor and a pressure sensor. The dynamic visual sensor collects dynamic visual event data of the deck wave process and reconstructs the wave impact evolution process through image processing. The pressure sensor is deployed on the platform deck surface to measure the magnitude of the wave impact load in real time.

[0009] Furthermore, the environmental simulation system includes a wind generation module, a wave generation and flow generation module, and a wave damping module. The wind generation module is configured to generate a steady wind field and a random turbulent wind field in the test water tank. The wave generation and flow generation module is configured to generate a wave field including regular waves, irregular waves, and focused waves, as well as a uniform flow field in the test water tank. The wave damping module is located at the end of the test water tank and is used to absorb wave energy to reduce the impact of reflected waves on the test.

[0010] Furthermore, the wind-generating module includes an elevator and a water jet wind tunnel. The elevator is used to adjust the height of the wind tunnel relative to the still water surface to adapt to the wind field simulation requirements of different test conditions.

[0011] Furthermore, the wave-generating and flow-generating module includes a wave-generating mechanism and a flow-generating mechanism. The wave-generating mechanism is equipped with multiple parallel-arranged rocker-type wave generators. The rocker-type wave generators are driven by servo motors and are used to generate regular waves, irregular waves, and focused waves. The flow-generating mechanism includes a flow-generating pump, which is used to regulate the water flow rate to generate a uniform flow field.

[0012] Furthermore, the photovoltaic module includes a photovoltaic panel and its supporting structure. The photovoltaic panel is made of high-strength organic material to realistically simulate wind load in a scaled-down model.

[0013] Furthermore, the floating assembly includes a platform deck, pontoons, and frame beams. The pontoons include multiple pontoons arranged on the periphery and a central pontoon, which are connected to each other via the frame beams. The platform deck is fixed to the upper part of the pontoons and is used to install photovoltaic modules and sensors. The pontoons are hollow structures, including hollow heave plates and hollow columns, to provide buoyancy. The frame beams are made of stainless steel tubing and include upper and lower beams to enhance the overall structural strength of the platform.

[0014] Furthermore, the platform deck is made of alloy plate processed into a hexagonal structure; the number of pontoons is seven, which are made of stainless steel plate, with six arranged on the periphery in a hexagonal pattern and one located in the center; the platform deck, the pontoons and the frame beams are fixedly connected by welding.

[0015] Furthermore, the mooring system includes a spring, a steel wire rope, and an anchor block, forming a four-point tensioned mooring arrangement, wherein one end of the spring is connected to the photovoltaic platform, and the other end is connected to the steel wire rope through a tension sensor, and the other end of the steel wire rope is anchored to the anchor block at the bottom of the pool.

[0016] Furthermore, the data measurement and acquisition system also includes an anemometer located upstream of the wind field, a current meter and a wave height meter located on the upstream and downstream sides of the platform, a tension sensor installed in the mooring system, and a displacement measurement system for measuring the six degrees of freedom motion of the platform.

[0017] Furthermore, the displacement measurement system includes a six-component target mounted on the platform and a high-speed camera arranged outside the pool, which calculates the six-degree-of-freedom displacement of the platform by capturing the target's motion.

[0018] Furthermore, the deck wave observation system is configured to perform the following processing to reconstruct the wave slamming evolution process based on event stream data recorded by dynamic visual sensors: The dynamic vision sensor operates in an event-driven manner, outputting an event stream consisting of pixel spatial coordinates, timestamps, and event polarities representing the direction of brightness changes. The continuous event stream is divided into a series of continuous and non-overlapping time windows according to a fixed number of events; For each time window, a spatiotemporal voxel grid is constructed, and each event within the window is interpolated along the time dimension according to its timestamp and polarity to be distributed to adjacent voxels, thereby encoding the event set into a tensor of fixed size. The tensor and the internal state of the recurrent convolutional neural network at the previous time step are input into the recurrent convolutional neural network. The internal state at the current time step is updated by its recurrent convolutional units, and the corresponding reconstructed image sequence is output by its image decoding head. Based on the reconstructed image sequence, the LK optical flow method is used. By calculating the partial derivatives of the image sequence in the spatial direction and the gradient in the temporal direction, and taking the constant optical flow in the neighborhood of the target pixel as a constraint, a set of optical flow equations is established. The least squares method is used to solve the set of equations to obtain the optical flow components, thereby calculating the target motion information between adjacent image sequences and reconstructing the morphological changes and nonlinear evolution process of wave impact.

[0019] The present invention has the following beneficial effects: This invention provides a floating photovoltaic dynamic response test device under extreme wind, wave, and current coupling effects, comprising an environmental simulation system, a semi-submersible photovoltaic platform system, a mooring system, and a data measurement and acquisition system. It constructs a complete test system capable of faithfully reproducing the coupling effects of various environmental loads such as wind, waves, and currents in a test pool. This test device can simulate the coupling effects of various environmental loads such as wind, waves, and currents in a water pool with high fidelity, realistically reproducing the actual operating conditions of floating photovoltaic platforms at sea, especially in extreme deep-sea conditions, thereby significantly improving the reliability of the test response results and their engineering guidance value.

[0020] Specifically, one of the core aspects of the experimental apparatus of this invention is the construction of a semi-submersible photovoltaic platform system suitable for deep-sea conditions. This invention deeply considers the influence of the photovoltaic modules themselves on the platform's dynamic response. The semi-submersible photovoltaic platform system not only includes a floating structure for providing buoyancy, but its photovoltaic modules are also constructed as a scaled-down model based on a floating photovoltaic platform prototype at a predetermined scale. This design ensures that in the scaled-down model test, the photovoltaic modules can realistically simulate and withstand wind loads, and their aerodynamic effects are accurately reflected in the platform's overall motion response. This compensates for the risk of insufficient platform motion response assessment caused by neglecting the aerodynamic loads of the photovoltaic modules in traditional tests, making the experimental analysis more comprehensive and accurate. This invention also pioneered the introduction of a dynamic visual sensor into the deck wave observation system for marine engineering model experiments. This dynamic visual sensor works in conjunction with pressure sensors arranged on the deck surface, overcoming the limitations of traditional high-speed cameras in scenarios with strong reflection, high dynamic range, and instantaneous obstruction. It can clearly capture and reconstruct the transient evolution process of nonlinear wave impact with microsecond-level response and ultra-high dynamic range, realizing complete and accurate physical observation and load measurement of the entire dynamic process of deck waves under extreme sea conditions. This provides a brand-new technical approach for in-depth research on impact loads and their impact on platform safety.

[0021] Furthermore, the experimental device of the present invention, through wind-generating, wave-generating, flow-generating, and wave-dissipating modules that can be independently controlled and operated in coordination, achieves accurate simulation of various wave patterns, from steady to random turbulent wind fields, from regular waves to focused waves, as well as uniform flow fields, thereby realistically reproducing the comprehensive stress environment of floating photovoltaic platforms at sea, especially in extreme conditions in the deep sea.

[0022] Furthermore, the floating components of the semi-submersible photovoltaic platform system consist of pontoons, frame beams, and a platform deck. In particular, the structure employing a hexagonal outer perimeter and a centrally arranged layout of seven pontoons welded to a stainless steel tubular frame gives the platform high strength, a large draft, and a high freeboard, resulting in a stable overall structure and laying the foundation for stability under harsh sea conditions. The mooring system utilizes a four-point tensioning arrangement including springs, wire ropes, and anchor blocks, providing the platform with controllable restoring stiffness and motion constraints, further enhancing its survivability and safety under the combined effects of wind, waves, and currents.

[0023] In summary, this invention can realistically and efficiently simulate and observe the comprehensive dynamic response of photovoltaic platforms under different sea conditions in complex marine environments, especially under the coupled effects of extreme wind, waves, and currents. It can fully observe the dynamic evolution of waves on the photovoltaic deck under extreme sea conditions, thereby facilitating and efficiently studying the hydrodynamic characteristics of floating photovoltaic platforms under the coupled effects of extreme wind, waves, and currents.

[0024] Other beneficial effects of the embodiments of the present invention will be further described below. Attached Figure Description

[0025] Figure 1 This is an elevation layout diagram of the floating photovoltaic dynamic response test device according to an embodiment of the present invention; Figure 2 This is a plan view of the floating photovoltaic dynamic response test device according to an embodiment of the present invention; Figure 3 This is a three-dimensional structural diagram of the semi-submersible photovoltaic platform system in an embodiment of the present invention; The attached figures are labeled as follows: 1-Elevator, 2-Water jet wind tunnel body, 3-Wave and current generation module, 4-Anemometer, 5-Current velocity meter, 6-Wave height meter, 7-Anchor block, 8-Wire rope, 9-Tension sensor, 10-Spring, 11-Six-component target, 12-Float, 13-Frame beam, 14-Photovoltaic module, 15-Pressure sensor, 16-High-speed camera, 17-Wave damping module, 18-Dynamic vision sensor, 19-Platform deck. Detailed Implementation

[0026] The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of the present invention.

[0027] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0028] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of the present invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0030] This invention aims to provide a dynamic response test device for a floating photovoltaic platform capable of high-fidelity simulation of the coupled effects of extreme environmental loads in deep-sea environments. By designing a test system that includes environmental simulation, a semi-submersible platform, mooring, and data acquisition, and innovatively constructing a scaled-down photovoltaic model based on a prototype, this invention introduces dynamic visual sensing technology. This overcomes the technical bottlenecks of traditional tests in realistically simulating wind loads and accurately observing waves on the deck. It can realistically reproduce the comprehensive stress and motion state of the platform under complex coupling of wind, waves, and currents. In particular, it achieves high-precision simulation of the aerodynamic effects of photovoltaic modules and clear capture of the nonlinear wave impact evolution process, thereby significantly improving the reliability, comprehensiveness, and engineering guidance value of the test analysis.

[0031] See Figures 1 to 3This invention provides a floating photovoltaic (PV) dynamic response test device under extreme wind, wave, and current coupling, comprising an environmental simulation system, a semi-submersible PV platform system, a mooring system, and a data measurement and acquisition system. The environmental simulation system generates controllable wind, wave, and current fields in a test pool to simulate the coupling effects of wind, wave, and current loads. The semi-submersible PV platform system is arranged in the test pool and simulates the hydrodynamic response of the floating PV platform under the loads generated by the environmental simulation system. The semi-submersible PV platform system includes PV modules 14 and a floating body assembly. The PV modules 14 are based on a floating PV platform prototype, constructed as a scaled-down model at a predetermined ratio, and positioned above the floating body assembly to bear wind loads and reflect the influence of the PV structure on the platform's motion. The floating body assembly bears wave loads, current loads, and wind loads, and provides support and buoyancy for the PV modules 14. The mooring system is connected at both ends to the semi-submersible PV platform system and the bottom of the test pool, respectively, providing restoring stiffness to the platform and constraining its motion. The data measurement and acquisition system uses various sensors deployed in the semi-submersible photovoltaic platform system and the test environment to collect data on the platform's six-degree-of-freedom motion response, mooring tension, deck wave load, and wave impact evolution under the coupled effects of wind, waves, and currents. The system includes a deck wave observation system, comprising a dynamic visual sensor 18 and a pressure sensor 15. The dynamic visual sensor 18 collects dynamic visual event data of the deck wave process and reconstructs the wave impact evolution process through image processing. The pressure sensor 15 is deployed on the surface of the platform deck 19 to measure the magnitude of the wave impact load in real time.

[0032] This experimental setup can realistically simulate the coupling effects of various environmental loads such as wind, waves, and currents in a water tank, accurately reproducing the actual operating conditions of a floating photovoltaic platform at sea, especially in extreme deep-sea conditions, thus significantly improving the reliability of the test response results. The semi-submersible photovoltaic platform system not only includes a floating structure to provide buoyancy, but its photovoltaic modules are also constructed as a scaled-down model based on the floating photovoltaic platform prototype. This design ensures that in the scaled-down model test, the photovoltaic modules can realistically simulate and withstand wind loads, and their aerodynamic effects are accurately reflected in the overall motion response of the platform. This compensates for the risk of insufficient platform motion response assessment due to neglecting the aerodynamic loads of photovoltaic modules in traditional tests, making the test analysis more comprehensive and accurate. By introducing dynamic visual sensors into the deck wave observation system, working in conjunction with pressure sensors arranged on the deck surface, the transient evolution process of nonlinear wave impacts can be clearly captured and reconstructed with microsecond-level response and ultra-high dynamic range, realizing complete and accurate physical observation and load measurement of the entire dynamic process of deck waves under extreme sea conditions.

[0033] See Figure 1 and Figure 2 In some embodiments, the environmental simulation system includes a wind-generating module, a wave-generating and flow-generating module 3, and a wave-dissipating module 17. The wind-generating module is configured to generate a steady wind field and a random turbulent wind field in the test pool. The wave-generating and flow-generating module 3 is configured to generate a wave field including regular waves, irregular waves, and focused waves, as well as a uniform flow field in the test pool. The wave-dissipating module 17 is located at the end of the test pool and is used to absorb wave energy to reduce the impact of reflected waves on the test.

[0034] See Figure 1 and Figure 2 In some embodiments, the wind-generating module includes a lift 1 and a water jet wind tunnel 2. The lift 1 is used to adjust the height of the water jet wind tunnel 2 relative to the still water surface to adapt to the wind field simulation requirements of different test conditions. In some embodiments, the wave-generating and flow-generating module 3 includes a wave-generating mechanism and a flow-generating mechanism. The wave-generating mechanism is equipped with multiple parallel-arranged rocker-type wave generators. The rocker-type wave generators are driven by servo motors and are used to generate regular waves, irregular waves, and focused waves. The flow-generating mechanism includes a flow-generating pump, which is used to regulate the water flow rate to generate a uniform flow field. The above embodiments, through wind-generating, wave-generating, flow-generating, and wave-dissipating modules that can be independently controlled and operated collaboratively, achieve accurate simulation of various wave patterns, from steady to random turbulent wind fields, from regular waves to focused waves, and uniform flow fields, thereby realistically reproducing the comprehensive stress environment of floating photovoltaic platforms at sea, especially in extreme deep-sea conditions.

[0035] See Figure 3 In some embodiments, the photovoltaic module 14 includes a photovoltaic panel and its supporting structure, the photovoltaic panel being made of a high-strength organic material to realistically simulate wind loads in a scaled-down model.

[0036] See Figures 1 to 3 In some embodiments, the floating body assembly includes a platform deck 19, floats 12, and frame beams 13. The floats 12 include multiple floats 12 arranged on the periphery and a float 12 located in the center. The floats 12 are connected to each other by the frame beams 13. The platform deck 19 is fixed to the upper part of the floats 12 and is used to install photovoltaic modules 14 and sensors. The floats 12 are hollow structures, including hollow heave plates and hollow columns, to provide buoyancy. The frame beams 13 are made of stainless steel tubes and include upper beams and lower beams to enhance the overall structural strength of the platform.

[0037] like Figure 3As shown, in some embodiments, the platform deck 19 is made of alloy plate and processed into a hexagonal structure; the number of pontoons 12 is seven, which are made of stainless steel plate, with six arranged on the periphery in a hexagonal pattern and one located in the center; the platform deck 19, the pontoons 12 and the frame beam 13 are fixedly connected by welding.

[0038] The aforementioned floating components adopt a design that combines pontoons, frame beams, and platform deck. In particular, the structure of seven pontoons with a hexagonal outer perimeter and a central layout, welded together with a stainless steel tube frame, gives the platform high strength, large draft, and high freeboard. The overall structure is stable, laying the foundation for maintaining stability in harsh sea conditions.

[0039] See Figure 1 and Figure 2 In some embodiments, the mooring system includes a spring 10, a steel wire rope 8, and an anchor block 7, forming a four-point tensioned mooring arrangement. One end of the spring 10 is connected to the photovoltaic platform, and the other end is connected to the steel wire rope 8 via a tension sensor 9. The other end of the steel wire rope 8 is anchored to the anchor block 7 at the bottom of the pool. The four-point tensioned arrangement achieved through the spring, steel wire rope, and anchor block provides controllable restoring stiffness and motion constraints for the platform, further enhancing its survivability and safety under the combined effects of wind, waves, and currents.

[0040] See Figure 1 and Figure 2 In some embodiments, the data measurement and acquisition system further includes an anemometer 4 located upstream of the wind field, a current meter 5 and a wave height meter 6 located on the upstream and downstream sides of the platform, a tension sensor 9 installed in the mooring system, and a displacement measurement system for measuring the six degrees of freedom motion of the platform.

[0041] See Figure 1 and Figure 2 In some embodiments, the displacement measurement system includes a six-component target 11 mounted on the platform and a high-speed camera 16 arranged outside the pool, which calculates the six-degree-of-freedom displacement of the platform by capturing the motion of the six-component target 11.

[0042] In some embodiments, the deck wave observation system is configured to perform the following processing to reconstruct the wave slamming evolution process based on event stream data recorded by a dynamic visual sensor: the dynamic visual sensor operates in an event-driven manner, outputting an event stream consisting of pixel spatial coordinates, timestamps, and event polarities representing the direction of brightness changes; the continuous event stream is divided into a series of continuous and non-overlapping time windows according to a fixed number of events; for each time window, a spatiotemporal voxel grid is constructed, and each event within the window is interpolated along the time dimension to be assigned to adjacent voxels according to its timestamp and polarity, thereby encoding the event set into a fixed-size [database / database]. Tensor; The tensor and the internal state of the recurrent convolutional neural network at the previous time step are input into the recurrent convolutional neural network. The internal state at the current time step is updated by its recurrent convolutional units, and the corresponding reconstructed image sequence is output by its image decoding head. Based on the reconstructed image sequence, the LK optical flow method is used. By calculating the partial derivatives of the image sequence in the spatial direction and the gradient in the temporal direction, and taking the constant optical flow in the neighborhood of the target pixel as a constraint, a set of optical flow equations is established. The least squares method is used to solve the set of equations to obtain the optical flow components, thereby calculating the target motion information between adjacent image sequences and reconstructing the morphological changes and nonlinear evolution process of wave impact.

[0043] The experimental device proposed in this invention can realistically and efficiently simulate and observe the comprehensive dynamic response of photovoltaic platforms under complex marine environments, especially under the coupled effects of extreme wind, waves, and currents, under different sea conditions. It can fully observe the dynamic evolution process of waves on the photovoltaic deck under extreme sea conditions, thereby facilitating and efficiently studying the hydrodynamic characteristics of floating photovoltaic platforms under the coupled effects of extreme wind, waves, and currents.

[0044] The features and advantages of specific embodiments of the present invention are further described below.

[0045] A floating photovoltaic dynamic response test device under extreme wind, wave and current coupling, such as Figure 1 and Figure 2 As shown. Specifically, the experimental setup includes an environmental simulation system, a semi-submersible photovoltaic platform system, a mooring system, and a data measurement and acquisition system. The environmental simulation system generates wind, wave, and flow fields, simulating the coupled effects of wind, wave, and current loads. The semi-submersible photovoltaic platform system simulates the hydrodynamic response of the photovoltaic platform under the combined effects of environmental loads and the mooring system. The mooring system is connected at both ends to the photovoltaic platform and the bottom of the pool, providing restoring stiffness for the platform. The data measurement and acquisition system uses multiple sensors to collect data on the six-degree-of-freedom motion displacement of the photovoltaic platform under the coupled effects of wind, wave, and current, as well as mooring tension, wave loads on the deck, and the evolution of nonlinear wave impacts.

[0046] Specifically, such as Figure 1 and Figure 2As shown, the environmental simulation system includes a wind-generating module, a wave-generating and flow-generating module 3, and a wave-dissipating module 17. The wind-generating module generates wind fields, including steady wind fields and random turbulent wind fields. The wave-generating and flow-generating module 3 generates wave fields and flow fields, including regular waves, irregular waves, and focused waves, and the flow field includes a uniform flow field. The wave-dissipating module 17 absorbs wave energy to reduce the influence of reflected waves. The wind-generating module includes a lift 1 and a water jet wind tunnel 2. The lift 1 adjusts the height of the water jet wind tunnel 2 above the still water surface to meet different operating conditions. The wave-generating and flow-generating module 3 includes a wave-generating mechanism and a flow-generating mechanism. The wave-generating mechanism is equipped with 10 parallel-arranged rocker-type wave generators, which are connected to servo motors for generating regular waves, irregular waves, and focused waves. The flow-generating mechanism is equipped with a flow-generating pump, which regulates the water flow rate to generate a flow field. The wave-generating and current-generating mechanisms input wave-generating and current-generating parameters through an external computer and corresponding software.

[0047] like Figure 1 and Figure 3 As shown, the semi-submersible photovoltaic platform system includes photovoltaic modules 14 and a floating body assembly. The photovoltaic modules 14 are used to withstand wind loads, simulating the influence of the photovoltaic structure on the platform's motion response. The floating body assembly is used to withstand wind loads, flow loads, and wave loads, and provides support for the photovoltaic modules 14. The photovoltaic modules 14 are made of high-strength organic materials, including the photovoltaic panels and supporting structure, which can effectively capture the effect of wind loads on the photovoltaic modules, preventing the underestimation of the response due to neglecting the influence of the photovoltaic modules. More specifically... Figure 3 As shown, the floating assembly includes a platform deck 19, floats 12, and a frame beam 13. The platform deck 19, made of alloy plate and shaped into a hexagon, provides support for the photovoltaic modules 14 and sensors. The floats 12, including hollow heave plates and hollow columns, provide buoyancy to the platform. The frame beam 13, consisting of an upper beam and a lower beam, connects the floats 12 and provides strength to the platform structure; it is made of stainless steel tubing. The floats 12, made of stainless steel plate, consist of six outer floats and one central float. The outer floats 12 are arranged in a hexagonal shape and then welded to the frame beam 13 and the platform deck 19.

[0048] like Figure 1 and Figure 2 As shown, the mooring system includes a spring 10, a steel cable 8, and an anchor block 7. One end of the spring 10 is connected to the photovoltaic platform, and the other end is connected to a tension sensor 9. The stiffness of the spring 10 depends on the mooring return stiffness requirement. One end of the steel cable 8 is connected to the tension sensor 9, and the other end is connected to the anchor block 7. A total of four moorings are set up to form a four-point tensioned mooring system.

[0049] like Figure 1 and Figure 2 As shown, the data measurement and acquisition system includes an anemometer 4, a current meter 5, a wave height meter 6, a tension sensor 9, a six-degree-of-freedom displacement measurement system, and a deck wave observation system. The anemometer 4 is positioned upstream of the wind field to measure wind speed. The current meter 5 and wave height meter 6 are positioned on the upstream and downstream sides of the floating platform to measure current velocity and wave height. The tension sensor 9 is positioned between the spring 10 and the wire rope 8 to measure mooring tension. The deck wave observation system includes a dynamic visual sensor 18 and a pressure sensor 15. The dynamic visual sensor 18 records event flow data of wave morphology changes on the deck. It can reconstruct wave image data using a convolutional neural network and use the LK optical flow method to track the target area to obtain wave morphology changes. The specific implementation is as follows.

[0050] The dynamic vision sensor operates in an event-driven manner, triggering events only when it detects a change in the scene, and outputting the address and information of the corresponding pixel whose light intensity has changed. Each event... e It can be represented as:

[0051] In the formula, ( x , y () represents the spatial coordinates of the event on the sensor plane. t Indicates the timestamp of the event. g This indicates the direction of grayscale change. Among them, g The range {+1, -1} indicates the direction of brightness change, where +1 represents increased brightness and -1 represents decreased brightness. When the cumulative brightness change of a pixel reaches a threshold ±... C The event is triggered at a certain time.

[0052] Furthermore, in order to transform a continuous stream of events into a sequence of images, the event stream is divided into a fixed number of events. N Cut into continuous, non-overlapping windows:

[0053] To adapt to the known processing requirements of convolutional neural networks, the window... Encoded as a fixed-size tensor E k A spatiotemporal voxel grid is used, with linear interpolation assignment performed in the time dimension. The window is... Duration of crossing Discretize the data into B time intervals. Assign polarity to each event as follows: p i Assigned to the two nearest spacetime voxels:

[0054] In the formula, This is a normalized event timestamp.

[0055] Furthermore, image reconstruction is achieved using a recurrent convolutional neural network, where the internal state... s k Updated over time. For each window. (Its tensor is) E k ), using the state of the previous time step s k-1 Output the current image sequence and update the status to s k :

[0056]

[0057] In the formula, f θ (•) represents a recursive convolution unit. g θ (•) is the image decoding head.

[0058] Furthermore, the classic LK optical flow method is used to calculate object motion information between adjacent image sequences, reconstructing a clear nonlinear wave impact evolution process. The LK method assumes that the optical flow is constant within the neighborhood of a pixel, and then uses the least squares method to solve the fundamental equations for all pixels in the neighborhood:

[0059]

[0060]

[0061] In the formula, q b For pixels within the window, b This represents the total number of pixels within the window. For p ∈[1,𝑏], I x ( q p )and I y ( q p (Images) I At pixel q p along x direction and y Partial derivatives in direction, It ( q p () represents the optical flow in time t The gradient at time. V x and V y Let be the optical flow component to be solved.

[0062] The dynamic vision sensor 18 boasts an ultra-high dynamic range exceeding 140dB, enabling it to clearly and accurately capture target events even in complex lighting environments with strong contrasts or drastic changes in brightness. Furthermore, the dynamic vision sensor 18's response speed reaches the microsecond level. The pressure sensor 15 is used to measure the magnitude of wave impact loads on the deck and analyze the impact of waves on the structure. The six-degree-of-freedom displacement measurement system includes a six-component target 11 and a high-speed camera 16. The six-component target 11 is equipped with photosensitive elements, and the high-speed camera 16 captures the target's motion displacement, which is then converted to obtain the motion of the photovoltaic platform.

[0063] Before the experiment began, a wave height meter 6 and a current meter 5 were installed in the test pool, and an anemometer 4 was placed at the outlet of the water jet wind tunnel 2 to calibrate the environmental conditions and determine the environmental parameters that should be input to the wind generation module and the wave generation and current generation module 3. Next, the test conditions were determined based on the experimental scale and the prototype, and the model was fabricated. The semi-submersible photovoltaic platform was placed in the center of the pool and moored. A pressure sensor 15 and a six-component target 11 were installed on the platform deck 19. After the equipment was debugged, the experiment began. The data measurement and acquisition system was started, and the environmental simulation system was opened to measure various dynamic response parameters of the semi-submersible photovoltaic platform system.

[0064] In summary, the floating photovoltaic dynamic response test device under extreme wind, wave, and current coupling effects provided by this invention has the following main technical advantages: Through the combination of high-fidelity environmental simulation, a structurally stable semi-submersible photovoltaic platform, a reliably constrained mooring system, and a precise data measurement and acquisition system, a complete physical model test device capable of realistically reproducing the multi-load coupling effects of extreme wind, wave, and current in deep-sea environments is constructed. Based on the semi-submersible photovoltaic platform, a photovoltaic module model based on the prototype and scaled-down construction is innovatively built, accurately simulating the wind load effect on the photovoltaic structure. Simultaneously, dynamic visual sensing methods are introduced, working in conjunction with pressure sensors, overcoming the limitations of traditional observation methods in scenarios with strong reflection and high dynamic range. This achieves clear capture and load measurement of the wave impact evolution process on the deck, significantly improving the realism of the experiment, observation accuracy, and analytical reliability, providing strong experimental support for the safety design and performance evaluation of floating photovoltaic platforms in deep-sea environments.

[0065] The above description provides a further detailed explanation of the present invention in conjunction with specific / preferred embodiments, and it should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and modifications can be made herein without departing from the scope of protection of the patent application.

Claims

1. A floating photovoltaic dynamic response test device under extreme wind, wave and current coupling, characterized in that, include: An environmental simulation system is used to generate controllable wind, wave, and flow fields in a test pool to simulate the coupling effects of wind, wave, and flow loads. A semi-submersible photovoltaic platform system is arranged in the test pool to simulate the hydrodynamic response of a floating photovoltaic platform under the loads generated by the environmental simulation system. The semi-submersible photovoltaic platform system includes photovoltaic modules and a floating body assembly. The photovoltaic modules are constructed as a scaled-down model based on a floating photovoltaic platform prototype at a predetermined scale and are placed above the floating body assembly to bear wind loads and reflect the influence of the photovoltaic structure on the platform's movement. The floating body assembly is used to bear wave loads, current loads, and wind loads, and to provide support and buoyancy for the photovoltaic modules. The mooring system, with its two ends connected to the semi-submersible photovoltaic platform system and the bottom of the test pool respectively, provides restoring stiffness to the platform and constrains its movement; The data measurement and acquisition system uses various sensors deployed in the semi-submersible photovoltaic platform system and the test environment to collect data on the platform's six-degree-of-freedom motion response, mooring tension, deck wave load, and wave impact evolution under the coupled effects of wind, waves, and currents. The system includes a deck wave observation system for observing deck waves, comprising a dynamic visual sensor and a pressure sensor. The dynamic visual sensor collects dynamic visual event data of the deck wave process and reconstructs the wave impact evolution process through image processing. The pressure sensor is deployed on the platform deck surface to measure the magnitude of the wave impact load in real time.

2. The test apparatus as described in claim 1, characterized in that, The environmental simulation system includes a wind generation module, a wave generation and flow generation module, and a wave damping module. The wind generation module is configured to generate a steady wind field and a random turbulent wind field in the test water tank. The wave generation and flow generation module is configured to generate a wave field including regular waves, irregular waves, and focused waves, as well as a uniform flow field in the test water tank. The wave damping module is located at the end of the test water tank and is used to absorb wave energy to reduce the impact of reflected waves on the test.

3. The test apparatus as described in claim 2, characterized in that, The wind-generating module includes an elevator and a water jet wind tunnel. The elevator is used to adjust the height of the wind tunnel relative to the still water surface to adapt to the wind field simulation requirements of different test conditions.

4. The test apparatus as described in claim 2, characterized in that, The wave-generating and flow-generating module includes a wave-generating mechanism and a flow-generating mechanism. The wave-generating mechanism is equipped with multiple parallel-arranged rocker-type wave generators. The rocker-type wave generators are driven by servo motors and are used to generate regular waves, irregular waves, and focused waves. The flow-generating mechanism includes a flow-generating pump, which is used to regulate the water flow rate to generate a uniform flow field.

5. The test apparatus according to any one of claims 1 to 4, characterized in that, The photovoltaic module includes a photovoltaic panel and its supporting structure. The photovoltaic panel is made of high-strength organic material to realistically simulate wind load in a scaled-down model.

6. The test apparatus according to any one of claims 1 to 4, characterized in that, The floating assembly includes a platform deck, pontoons, and frame beams. Each pontoon comprises multiple pontoons arranged on the periphery and a central pontoon, connected by the frame beams. The platform deck is fixed to the upper part of the pontoons and is used to install photovoltaic modules and sensors. Each pontoon is a hollow structure, including a hollow heave plate and hollow columns, used to provide buoyancy. The frame beams are made of stainless steel tubing, including upper and lower beams, used to enhance the overall structural strength of the platform. The platform deck is made of alloy plate processed into a hexagonal structure. There are seven pontoons, all made of stainless steel, with six arranged hexagonally on the periphery and one in the center. The platform deck, the pontoons, and the frame beams are fixedly connected by welding.

7. The test apparatus according to any one of claims 1 to 4, characterized in that, The mooring system includes a spring, a steel wire rope, and an anchor block, forming a four-point tensioned mooring arrangement. One end of the spring is connected to the photovoltaic platform, and the other end is connected to the steel wire rope via a tension sensor. The other end of the steel wire rope is anchored to the anchor block at the bottom of the pool.

8. The test apparatus according to any one of claims 1 to 4, characterized in that, The data measurement and acquisition system also includes an anemometer located upstream of the wind field, a current meter and a wave height meter located on the upstream and downstream sides of the platform, a tension sensor installed in the mooring system, and a displacement measurement system for measuring the six degrees of freedom motion of the platform.

9. The test apparatus as described in claim 8, characterized in that, The displacement measurement system includes a six-component target mounted on the platform and a high-speed camera positioned outside the pool. It calculates the six-degree-of-freedom displacement of the platform by capturing the target's motion.

10. The test apparatus according to any one of claims 1 to 4, characterized in that, The deck wave observation system is configured to perform the following processing to reconstruct the wave slamming evolution process based on event stream data recorded by dynamic visual sensors: The dynamic vision sensor operates in an event-driven manner, outputting an event stream consisting of pixel spatial coordinates, timestamps, and event polarities representing the direction of brightness changes. Divide a continuous event stream into a series of consecutive and non-overlapping time windows based on a fixed number of events; For each time window, a spatiotemporal voxel grid is constructed, and each event within the window is interpolated along the time dimension according to its timestamp and polarity to be distributed to adjacent voxels, thereby encoding the event set into a tensor of fixed size. The tensor and the internal state of the recurrent convolutional neural network at the previous time step are input into the recurrent convolutional neural network. The internal state at the current time step is updated by its recurrent convolutional units, and the corresponding reconstructed image sequence is output by its image decoding head. Based on the reconstructed image sequence, the LK optical flow method is used. By calculating the partial derivatives of the image sequence in the spatial direction and the gradient in the temporal direction, and taking the constant optical flow in the neighborhood of the target pixel as a constraint, a set of optical flow equations is established. The least squares method is used to solve the set of equations to obtain the optical flow components, thereby calculating the target motion information between adjacent image sequences and reconstructing the morphological changes and nonlinear evolution process of wave impact.

Images