Novel hybrid pile rigid-flexible self-balanced system offshore photovoltaic platform system

Abstract

The application provides an offshore photovoltaic platform system of a new type of rigid-flexible self-balancing system of a hybrid pile, which comprises a hybrid pile and an offshore photovoltaic platform of a rigid-flexible self-balancing system, the hybrid pile is composed of a PHC pile and a steel pipe pile; the offshore photovoltaic platform of the rigid-flexible self-balancing system adopts a square evacuated four-corner pyramid space truss structure as a whole, an evacuation is additionally performed on the middle part of the space truss, prestressed steel strands are used to connect the middle evacuated parts, main purlins and secondary purlins are arranged on the upper part of the space truss, four main nodes are arranged on the lower part of the space truss, and the main nodes are connected with the lower pile foundation. No other supporting structure is arranged on the lower part of the offshore photovoltaic platform, the offshore photovoltaic platform can be fixed on a barge through a transportation fixing tool, and two platforms can be stacked. The application solves the problems of limited bearing capacity of the PHC pile and high cost of the steel pipe pile, fully combines the advantages of the two, solves the problems of large steel consumption, many manufacturing procedures, low construction efficiency and low construction precision of the offshore photovoltaic platform, and reduces the engineering cost as a whole.

Description

Technical Field

[0001] This invention relates to the field of offshore photovoltaic power generation, specifically to an offshore photovoltaic platform system with a novel hybrid pile rigid-flexible self-balancing system. Background Technology

[0002] Offshore photovoltaic (PV) platforms are currently in use in the offshore PV industry. They typically consist of a subfoundation and an upper support structure. The subfoundation uses steel pipe piles, while the upper support structure is a truss or space frame structure with purlins installed on it. The PV modules are then connected to the purlins via bolts. However, current offshore PV support systems still face the following insurmountable problems: 1. High cost of pile foundations. Traditional offshore photovoltaic (PV) systems typically use PHC (Polyhydrogen Hydrocarbon) piles, but due to the large number of piles required, the cost is high, significantly impacting the construction period. Furthermore, these piles are susceptible to wave and tidal influences, making them generally suitable for shallow waters or shallow areas. Therefore, for offshore PV systems, steel pipe pile foundations are typically used. This achieves greater load-bearing capacity while significantly reducing the number of piles required, and it can also adapt to different water depths. However, since steel pipe piles are much more expensive than concrete pipe piles, selecting the appropriate pile foundation is crucial.

[0003] 2. The cost of the superstructure is relatively high, the construction period is long, and the requirements for the dock are high. The superstructure support usually consists of truss structures and space frame structures. Compared with space frame structures, truss structures are lighter in overall steel structure weight, but because their construction and fabrication need to be carried out in open areas and require assembly line operations to meet continuous construction requirements, they have higher requirements for the dock. Due to the load-bearing performance of space frame structures, which require main purlins and secondary purlins to fix photovoltaic modules, their overall steel structure weight is greater. However, space frame structures can be prefabricated in the factory and only need to be assembled at the dock, resulting in higher overall efficiency and lower requirements for the dock.

[0004] In conclusion, existing offshore photovoltaic platform systems still have shortcomings, especially with the major reforms to the new energy electricity pricing mechanism, which place increasingly stringent demands on engineering costs. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a novel photovoltaic support structure for offshore photovoltaic platform systems, incorporating a hybrid pile and a rigid-flexible self-balancing system. This structure solves the problem of insufficient bending resistance in PHC piles, while also offering lower costs and greater construction feasibility compared to steel pipe piles, thus reducing project expenses. Furthermore, it can reduce the amount of steel used in offshore photovoltaic platforms and shorten the construction period. To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: A novel hybrid pile-based rigid-flexible self-balancing offshore photovoltaic system includes a pile foundation and an offshore photovoltaic platform support system. Its key features are: the pile foundation uses hybrid piles, with each offshore photovoltaic platform supported by four hybrid piles of varying heights, allowing the photovoltaic platform to have a certain tilt angle; the offshore photovoltaic platform is equipped with purlins, and photovoltaic modules are bolted to the purlins; the entire offshore photovoltaic platform is manufactured on land and ultimately placed on the hybrid piles via hoisting. The hybrid pile consists of PHC pile segments at both ends and a steel pipe pile segment in the middle. The height range of the steel pipe pile segment covers the wave action range, and the three segments are connected by welding. The offshore photovoltaic platform consists of upper chord members, web members, lower chord members, bolted ball joints, prestressed steel strands, and pile head connection mechanisms. The overall structure is a rectangular hollowed-out quadrangular pyramidal grid structure. The entire platform is hollowed out in the middle, with only some web members remaining. The top of the grid is connected with prestressed steel strands to form a whole.

[0006] Based on the above technical solutions, the present invention may also employ the following further technical solutions, or combine these further technical solutions: The PHC pile segment is a variable-diameter pile, with a smaller diameter at the end of the entire new hybrid pile and a larger diameter at the middle. It contains prestressed steel bars and includes a variable-diameter section and a large-diameter section. In addition to the prestressed steel bars, non-prestressed steel bars are also provided in the variable-diameter section and the large-diameter section. The top of the PHC pile segment is provided with a pile end plate with a central hole. The inner diameter of the pile end plate is smaller than the inner diameter of the pile. The top of the hybrid pile is provided with a pile retaining plate, and a steel bar is connected to the pile end plate and the pile retaining plate. The steel bar passes obliquely through the PHC pile segment. A stiffening plate is welded to the inner wall of the end of the steel pipe pile segment and is welded to the pile end plate. Finally, the three pile segments are connected to form a hybrid pile.

[0007] The prestressed steel strand is provided with steel strand sleeves at both ends, and the ends of the steel strand sleeves are processed into steel strand end bolts, which are threadedly connected to the bolt ball joints.

[0008] The pile head connection mechanism is composed of a tip stiffening plate, a tip circular plate, and a tip welded together. The tip stiffening plate is welded to the bolt ball joint and the tip circular plate. The tip is welded below the tip circular plate. When the pile is installed on the hybrid pile on the offshore photovoltaic platform, the tip is inserted into the hole of the pile end plate, and the tip circular plate is welded to the pile end plate. The diameter of the tip circular plate is smaller than the outer diameter of the pile end plate.

[0009] The purlins include main purlins, secondary purlins, purlin brackets, and U-bolts. The main purlins are made of I-beams. The purlin brackets have internal purlin bracket fixing bolts that secure them to the bolt ball joints. The upper part of the purlin bracket is connected to the main purlin via the main purlin fixing bolts. A main purlin liner is placed between the main purlin and the main purlin fixing bolts to provide local reinforcement. A main purlin stiffening plate is welded between the upper and lower flanges of the main purlin. The secondary purlins are connected to the main purlin stiffening plate via main-secondary purlin connecting bolts. The secondary purlins are perpendicular to the main purlins and are short profiles with a U-shaped cross-section. The U-bolt is equipped with a lower U-bolt washer, an upper U-bolt washer, a photovoltaic pressure block, a U-bolt nut, and a module fixing bolt. The U-bolt is used to fix the photovoltaic module to the secondary purlin. The photovoltaic pressure block has a hole and presses the photovoltaic module in place. The U-bolt passes through the hole. The upper U-bolt washer is placed between the photovoltaic module and the secondary purlin. The lower U-bolt washer is placed under the secondary purlin. The U-bolt passes through the upper and lower U-bolt washers and extends beyond the secondary purlin. It is fixed by the U-bolt nut.

[0010] The system includes a first support and a second support. The first support includes a cable tray, clamps, and support fixing rods. The support fixing rods are connected between two clamps, and cable trays are laid on the support fixing rods. The second support includes an inverter platform and clamps. An inverter fixing rod is set on the inverter platform, and the inverter platform is connected to four clamps. The clamps are fixed to the web members of the grid structure.

[0011] Another object of the present invention is to provide a construction method for a novel hybrid pile rigid-flexible self-balancing system for offshore photovoltaic platforms, the construction method comprising the following steps: S1: The hybrid piles are manufactured as a whole in the prefabrication plant, and then transported to the construction site by barge. The piles are then positioned using a positioning system and finally driven to the design elevation. S2: Offshore Photovoltaic Platform Manufacturing: At the onshore construction plant, the upper chord, web members, lower chord, bolted ball joints, and pile heads of the space frame are assembled. Then, prestressed steel strand bolts are fixed to the bolted ball joints, holes are drilled at the steel strand sleeve positions, and prestressing is performed to complete the structural assembly of the entire platform. Next, the main purlins, secondary purlins, photovoltaic modules, supports, and inverters are installed sequentially. Finally, anti-corrosion work is carried out at the bolted ball joints, completing the manufacturing of the offshore photovoltaic platform. S3: Offshore photovoltaic platform transportation: The manufactured offshore photovoltaic platform is hoisted onto the transport barge by the crane at the dock. The barge is equipped with transport fixtures to stack two offshore photovoltaic platforms together and transport them to the construction site. S4: Installation of offshore photovoltaic platform: The offshore photovoltaic platform is hoisted onto the pile foundation by slings. The lower sling is tied to the bolt ball joint between the upper chord of the grid frame. The four pins under the platform are inserted into the pile. Construction workers can weld the pin round plates to the pile end plates on site at the bolt ball position. S5: Connect the cables between the various offshore photovoltaic platforms after installation, and lay the cables between the photovoltaic module modules along the cable tray; the total cables are connected to the box-type transformer to complete the installation of the offshore photovoltaic power plant.

[0012] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. This invention employs a novel hybrid pile foundation, composed of PHC piles and steel pipe piles connected together. Its cost is lower than that of steel pipe piles, and it meets the characteristics of offshore photovoltaic systems under wave, current, and wind loads, where the bending moments at both ends of the pile are small, while the bending moments in the middle are large. Typically, PHC piles, due to their limited bending resistance, cannot meet the load requirements under large bending moment conditions, while steel pipe piles, with their excellent stiffness and bending resistance, perfectly meet the requirement of large bending moments in the middle of the pile. Furthermore, because the end area of ​​PHC piles is larger than that of steel pipe piles, under geological conditions with end resistance, their end resistance is higher than that of steel pipe piles, thereby improving the overall bearing capacity of the pile foundation.

[0013] 2. The novel hybrid pile foundation PHC pile segment of this invention adopts a variable diameter type, with a smaller diameter at the end and a larger diameter in the middle, which conforms to the stress characteristics of photovoltaic pile foundations under marine environmental conditions. The smaller diameter can reduce the load of wave flow and reduce the scouring depth, thereby reducing the load on the entire pile body.

[0014] 3. This invention employs a rigid-flexible self-balancing photovoltaic support structure. The overall structure utilizes a grid frame design, which reduces site requirements during assembly and significantly lowers dock rental costs. The hollowed-out space frame utilizes prestressed steel strand cables, saving on the amount of steel used in the grid frame and effectively reducing project costs. The entire photovoltaic support structure is manufactured onshore, greatly reducing offshore construction procedures.

[0015] 4. The photovoltaic support structure used in this invention is directly connected to the top of the pile at its bottom, without the need for other supporting connecting rods. The entire platform can be used to complete the operation on a plane, and the stacking and transportation can be carried out by making tooling during the transportation process, which can greatly improve the construction efficiency.

[0016] 5. In the connection between the photovoltaic support structure and the top of the pile of the present invention, the steel plate on the tip is smaller than the steel plate on the top of the pile. During on-site welding operations, the operators can weld downwards at the bolt ball joint without setting up a basket to weld upwards, which provides safer and more convenient working conditions and reduces the need for ships in the entire project.

[0017] 6. In this invention, the main purlins are made of I-beams, and the secondary purlins are made of C-beams. The two are connected by stiffening plate bolts. The secondary purlins are located between the main purlins and are approximately 5-6 meters long. This not only reduces transportation difficulties but, more importantly, minimizes deformation of the secondary purlins. Traditional offshore photovoltaic purlins are often thin-walled and long, making deformation difficult to control and further complicating the installation of photovoltaic modules.

[0018] 7. The photovoltaic module installation of this invention uses U-bolts to pass through the secondary purlins and fix them thereon. This solves the problem that the traditional photovoltaic module installation uses long bolts to fix the modules by drilling holes in the secondary purlins, which often leads to installation failure due to deformation of the secondary purlins. If the installation is done by drilling holes on site, the construction efficiency is extremely low. The use of U-bolts greatly reduces the construction difficulty and significantly improves the construction efficiency.

[0019] 8. In this invention, both the cable tray and the inverter are fixed to the web members of the grid structure using clamps, which meets the stress characteristics of the grid structure. At the same time, the clamp fixing eliminates the need for welding, reducing construction time. Attached Figure Description

[0020] Figure 1 This is a side view of the rigid-flexible self-balancing system of the novel hybrid pile of the present invention for an offshore photovoltaic platform; Figure 2 This is a diagram of the novel hybrid pile foundation of the present invention; Figure 3 This is the reinforcement diagram of the PHC section of the novel hybrid pile foundation of this invention; Figure 4 This is a diagram of the novel hybrid pile top structure of the present invention; Figure 5 This is a diagram of the novel hybrid pile splicing method of the present invention; Figure 6 This is a plan view of the offshore photovoltaic platform based on the rigid-flexible self-balancing system of this invention; Figure 7 This is a cross-sectional view of the offshore photovoltaic platform structure of the rigid-flexible self-balancing system of the present invention; Figure 8 This is a schematic diagram of the spigot structure of the rigid-flexible self-balancing system of the present invention for a marine photovoltaic platform; Figure 9-1 This is a front view of the prestressed steel strand structure of the present invention; Figure 9-2 This is a cross-sectional view of the prestressed steel strand structure of the present invention; Figure 10 This is an elevation view of the main purlin connection of the present invention; Figure 11 This is a cross-sectional view of the main purlin connection of the present invention; Figure 12 This is an elevation view of the secondary purlin connection of the present invention; Figure 13This is a cross-sectional view of the secondary purlin of the present invention; Figure 14 This is a diagram of the U-shaped bolt of the present invention; Figure 15-1 and Figure 15-2 These are plan views of the steel plate that is used in conjunction with the U-bolt of this invention; Figure 16-1 , Figure 16-2 and Figure 16-3 These are, respectively, a side view, a front view, and a top view of the pressing block of the present invention; Figure 17 This is a diagram of the cable tray installation of the present invention; Figure 18 This is an inverter installation diagram of the present invention; Figure 19 This is a detailed drawing of the clamp fixing of the present invention; Figure 20 This is a detailed drawing of the inverter platform of the present invention; Figure 21 This is a top view of the offshore photovoltaic platform transporting the rigid-flexible self-balancing system of the present invention; Figure 22 This is a transportation elevation view of the offshore photovoltaic platform of the rigid-flexible self-balancing system of the present invention; Figure 23 This is a hoisting and installation diagram of the offshore photovoltaic platform using the rigid-flexible self-balancing system of this invention.

[0021] Reference numerals: 1-New type of hybrid pile; 11-PHC pile segment; 111-Prestressed steel bar; 112-Non-prestressed steel bar; 113-Pile end plate; 114-Pile sheath plate; 115-Steel bar; 116-Silane impregnation for corrosion protection; 12-Steel pipe pile segment; 121-Stiffening plate; 122-Anti-corrosion paint; 2-Offshore photovoltaic platform; 21-Upper chord of space frame; 22-Web member of space frame; 23-Lower chord of space frame; 24-Bolt ball joint; 25-Prestressed steel strand; 251-Steel strand sleeve; 252-Steel strand end bolt; 26-Pile head connection mechanism; 261-Point stiffening plate; 262-Point round plate; 263-Point; 3-Purlin; 31-Main purlin ; 311-Main purlin stiffening plate; 312-Main and secondary purlin connecting bolts; 32-Secondary purlin strip; 33-Purlin bracket; 331-Purlin bracket fixing bolt; 332-Main purlin mounting plate; 333-Main purlin fixing bolt; 34-U-bolt; 341-U-bolt lower washer; 342-U-bolt upper washer; 343-Photovoltaic pressure block; 344-U-bolt nut; 345-Module fixing bolt; 4-Photovoltaic module; 5-Bracket; 51-Cable tray; 52-Clamping clamp; 53-Bracket fixing rod; 54-Bracket connecting rod; 55-Inverter platform; 56-Inverter fixing rod; 6-Inverter; 7-Transport barge; 8-Transport fixing fixture; 9-Lifting sling; 91-Lifting rope. Detailed Implementation

[0022] To enable those skilled in the art to better understand the technical solutions of the present invention, preferred embodiments of the present invention are described below in conjunction with specific examples. However, it should be understood that the accompanying drawings are for illustrative purposes only and should not be construed as limiting the present invention. For better illustration of this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable that some well-known structures and their descriptions may be omitted in the drawings for those skilled in the art. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting the present invention.

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0024] like Figures 1 to 23 As shown, the novel hybrid pile rigid-flexible self-balancing offshore photovoltaic system of the present invention includes a pile foundation and an offshore photovoltaic platform support system. The pile foundation uses novel hybrid piles 1, with a total of four novel hybrid piles 1 for each offshore photovoltaic platform 2. The pile heights of the front and rear piles are inconsistent, giving the photovoltaic platform a certain tilt angle. The offshore photovoltaic platform 2 is equipped with purlins 3, and photovoltaic modules 4 are fixed to the purlins 3 by bolts. After the offshore photovoltaic platform 2 is manufactured at the onshore base, it is transported to the project site by barge 6 and finally placed on the novel hybrid piles 1 by hoisting.

[0025] like Figures 2 to 5 As shown, the novel hybrid pile 1 has PHC pile segments 11 at both ends and a steel pipe pile segment 12 in the middle. The height range of the steel pipe pile segment 12 covers the wave action range, and the three segments are connected by welding. The PHC pile segment 11 is a variable diameter pile, with a smaller diameter at the end of the entire novel hybrid pile 1 and a larger diameter at the middle position (i.e., the part of the PHC pile segment 11 near the steel pipe pile segment 12 at both ends). It contains prestressed steel bars 111, including a variable diameter section and a large diameter section. In addition to the prestressed steel bars 111, non-prestressed steel bars 112 are also provided in the variable diameter section and the large diameter section. A pile end plate 113 is provided at the top of the PHC pile segment, which has a central hole. The inner diameter of the pile end plate 113 is smaller than the inner diameter of the pile, which can solve the welding difficulties caused by on-site construction errors. A pile retaining plate 114 is provided at the top of the hybrid pile, and a steel rod 115 is connected to the pile end plate 113 and the pile retaining plate 114; the steel rod 115 passes through the PHC pile segment at an angle. The portion of the PHC pile segment 11 above the mud surface is coated with a silane-impregnated anti-corrosion material 116. The steel pipe pile segment 12 is made of rolled steel plate, and the outer surface of the steel pipe column above the mud surface is coated with anti-corrosion paint 122. Twelve stiffening plates 121 are welded to the inner wall of the end of the steel pipe pile segment 12 and welded to the pile end plate 113. Finally, the three pile segments are connected to form a new type of hybrid pile 1.

[0026] like Figures 6 to 8 As shown, the offshore photovoltaic platform 2 comprises an upper chord 21, web members 22, lower chord 23, bolted ball joints 24, prestressed steel strands 25, and a pile head connection mechanism 26. Its overall structure is a square hollowed-out pyramidal grid structure, with the top side longer than the bottom side. The platform is hollowed out in the middle, retaining only a portion of the web members 22. Prestressed steel strands 25 are used to connect the top of the grid (between the opposite upper chord members 21) to form a whole. Figure 9-1 , 9-2 As shown, the prestressed steel strand 25 is provided with steel strand sleeves 251 at both ends. The ends of the steel strand sleeves 251 are processed into steel strand end bolts 252, which are threadedly connected to the bolt ball joint 24. The pile head connection mechanism 26 is welded together from a tip stiffening plate 261, a tip circular plate 262, and a tip 263. The tip stiffening plate 261 is welded to the bolt ball joint 24 and the tip circular plate 262, and the tip 263 is welded below the tip circular plate 262. When the offshore photovoltaic platform 2 is installed on the new hybrid pile 1, the tip 263 is inserted into the hole of the pile end plate 113, and the tip circular plate 262 is welded to the pile end plate 113. The diameter of the tip circular plate 262 is smaller than the outer diameter of the pile end plate 113.

[0027] like Figures 10 to 1 5 and Figure 16-1 , Figure 16-2As shown, the purlin 3 includes a main purlin 31, a secondary purlin 32, a purlin bracket 33, and U-bolts 34. The main purlin 31 is made of I-beam. The purlin bracket 33 has a purlin bracket fixing bolt 331 inside, which fixes it to the bolt ball joint 24. The upper part of the purlin bracket 33 is connected to the main purlin 31 through the main purlin fixing bolt 333. The main purlin plate 332 is placed between the main purlin 31 and the main purlin fixing bolt 333, which plays a local reinforcement role. The main purlin stiffening plate 311 is welded between the upper and lower flange plates of the main purlin 31. The secondary purlin 32 is connected to the main purlin stiffening plate 311 through the main and secondary purlin connecting bolts 312. The secondary purlin 32 is perpendicular to the main purlin 31 and is a short profile with a U-shaped cross section. The photovoltaic module 4 is fixed on the secondary purlin 32. The U-bolt 34 is equipped with a lower U-bolt washer 341, an upper U-bolt washer 342, a photovoltaic pressure block 343, a U-bolt nut 344, and a module fixing bolt 345. The U-bolt 34 is used to fix the photovoltaic module 4 to the secondary purlin 32. The photovoltaic pressure block 343 has a hole to hold the photovoltaic module 4 in place, through which the U-bolt 34 passes. The upper U-bolt washer 342 is placed between the photovoltaic module 4 and the secondary purlin 32, and the lower U-bolt washer 341 is placed under the secondary purlin 32. The U-bolt 34 passes through the upper U-bolt washer 342 and the lower U-bolt washer 341, extending beyond the secondary purlin 32, and is fixed by the U-bolt nut 344. Additionally, the photovoltaic module 4 is further fixed to the upper U-bolt washer 342 using a module fixing bolt 345. The reference numeral 346 in the attached diagram is the bolt hole for the upper pad 342 and the bolt 345 to mate; the reference numeral 347 in the attached diagram is the bolt hole for the upper pad 342, the photovoltaic pressure block 343, the lower pad 342 and the U-bolt 34 to mate; and the reference numeral 348 in the attached diagram is the adjustment hole for the upper pad 342 and the bolt 345 to mate.

[0028] like Figures 17 to 20 As shown, the offshore photovoltaic platform 2 includes a first support 5 and a second support, which are fixed to the offshore photovoltaic platform 2. The first support 5 includes a cable tray 51, clamps 52, support fixing rods 53, and support connecting rods 54. The clamps 52 are fixed to the web members 22 of the grid structure, and the support fixing rods 53 connect the two clamps 52. The cable tray 51 is laid on the support fixing rods 53, and support connecting rods 54 are usually arranged on both sides to prevent the cable tray 51 from shifting. One to two inverters 6 are required on a single offshore photovoltaic platform 2 depending on the capacity of the photovoltaic modules. The second support includes an inverter platform 55, clamps 52, and inverter platform 55 is equipped with inverter fixing rods 56. The inverters 6 are placed on the inverter platform 55 and fixed by connecting to the inverter fixing rods 56. The inverter platform 55 is connected to the web members 22 of the grid structure by four clamps 52.

[0029] This invention also provides a construction method for a novel hybrid pile rigid-flexible self-balancing system for offshore photovoltaic platforms, the construction method comprising the following steps: S1: The new type of hybrid pile 1 is manufactured as a whole in the prefabrication plant, and then the pile foundation is transported to the construction site by barge. The pile foundation is positioned by the positioning system and finally driven to the design elevation.

[0030] S2: Manufacturing of Offshore Photovoltaic Platform 2: At the onshore construction plant, the upper chord 21, web members 22, lower chord 23, bolted ball joints 24, and pile head connections 26 of the space frame are assembled. Then, prestressed steel strand bolts 252 are fixed to the bolted ball joints 24, and holes are drilled at the positions of the steel strand sleeves 251. Prestressing is then performed to complete the structural assembly of the entire platform. Subsequently, the main purlins, secondary purlins, photovoltaic modules, supports, and inverters are installed sequentially. Finally, anti-corrosion work is carried out at the bolted ball joints 24, completing the manufacturing of Offshore Photovoltaic Platform 2.

[0031] S3: Transportation of offshore photovoltaic platform 2: The completed offshore photovoltaic platform 2 is hoisted onto the transport barge 7 by the crane at the dock. The barge is equipped with transport fixing fixtures 8, which are stacked together and transported to the construction site.

[0032] S4: Installation of offshore photovoltaic platform 2: The offshore photovoltaic platform 2 is hoisted onto the pile foundation by slings 9. The slings 9 are tied to the bolt ball nodes 24 between the upper chords 21 of the grid frame by the lower slings 9. The four pins 263 below the platform are inserted into the piles 11. Construction workers can weld the pin round plates 262 to the pile end plates 113 on site at the bolt ball 24 position.

[0033] S5: Connect the cables between the various offshore photovoltaic platforms 2 after installation, and lay the cables between the photovoltaic module modules along the cable tray; the total cables are connected to the box-type transformer to complete the installation of the offshore photovoltaic power plant.

[0034] Based on the description and accompanying drawings of this invention, those skilled in the art can easily manufacture or use the offshore photovoltaic platform system of the novel hybrid pile rigid-flexible self-balancing system of this invention, and can produce the positive effects described in this invention.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications or equivalent changes made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A novel hybrid pile-based rigid-flexible self-balancing offshore photovoltaic system, comprising pile foundations and an offshore photovoltaic platform support system. Its characteristics are: The aforementioned pile foundation adopts a hybrid pile, with a total of 4 hybrid piles for a single offshore photovoltaic platform. The heights of the front and rear piles are inconsistent, giving the photovoltaic platform a certain tilt angle. The offshore photovoltaic platform is equipped with purlins, and the photovoltaic modules are fixed to the purlins with bolts. The entire offshore photovoltaic platform is manufactured on land and finally placed on the hybrid piles by hoisting. The hybrid pile consists of PHC pile segments at both ends and a steel pipe pile segment in the middle. The height range of the steel pipe pile segment covers the wave action range, and the three segments are connected by welding. The offshore photovoltaic platform consists of upper chord members, web members, lower chord members, bolted ball joints, prestressed steel strands, and pile head connection mechanisms. The overall structure is a rectangular hollowed-out quadrangular pyramidal grid structure. The entire platform is hollowed out in the middle, with only some web members remaining. The top of the grid is connected with prestressed steel strands to form a whole.

2. The novel hybrid pile rigid-flexible self-balancing marine photovoltaic system according to claim 1, characterized in that: The PHC pile segment is a variable-diameter pile, with a smaller diameter at the end of the entire new hybrid pile and a larger diameter at the middle. It contains prestressed steel bars and includes a variable-diameter section and a large-diameter section. In addition to the prestressed steel bars, non-prestressed steel bars are also provided in the variable-diameter section and the large-diameter section. The top of the PHC pile segment is provided with a pile end plate with a central hole. The inner diameter of the pile end plate is smaller than the inner diameter of the pile. The top of the hybrid pile is provided with a pile retaining plate, and a steel bar is connected to the pile end plate and the pile retaining plate. The steel bar passes obliquely through the PHC pile segment. A stiffening plate is welded to the inner wall of the end of the steel pipe pile segment and is welded to the pile end plate. Finally, the three pile segments are connected to form a hybrid pile.

3. The novel hybrid pile rigid-flexible self-balancing marine photovoltaic system according to claim 1, characterized in that: The prestressed steel strand is provided with steel strand sleeves at both ends, and the ends of the steel strand sleeves are processed into steel strand end bolts, which are threadedly connected to the bolt ball joints.

4. The novel hybrid pile rigid-flexible self-balancing marine photovoltaic system according to claim 1, characterized in that: The pile head connection mechanism is composed of a tip stiffening plate, a tip circular plate, and a tip welded together. The tip stiffening plate is welded to the bolt ball joint and the tip circular plate. The tip is welded below the tip circular plate. When the pile is installed on the hybrid pile on the offshore photovoltaic platform, the tip is inserted into the hole of the pile end plate, and the tip circular plate is welded to the pile end plate. The diameter of the tip circular plate is smaller than the outer diameter of the pile end plate.

5. The novel hybrid pile rigid-flexible self-balancing marine photovoltaic system according to claim 1, characterized in that: The purlins include main purlins, secondary purlins, purlin brackets, and U-bolts. The main purlins are made of I-beams. The purlin brackets have internal purlin bracket fixing bolts that secure them to the bolt ball joints. The upper part of the purlin bracket is connected to the main purlin via the main purlin fixing bolts. A main purlin liner is placed between the main purlin and the main purlin fixing bolts to provide local reinforcement. A main purlin stiffening plate is welded between the upper and lower flanges of the main purlin. The secondary purlins are connected to the main purlin stiffening plate via main-secondary purlin connecting bolts. The secondary purlins are perpendicular to the main purlins and are short profiles with a U-shaped cross-section. The U-bolt is equipped with a lower U-bolt washer, an upper U-bolt washer, a photovoltaic pressure block, a U-bolt nut, and a module fixing bolt. The U-bolt is used to fix the photovoltaic module to the secondary purlin. The photovoltaic pressure block has a hole and presses the photovoltaic module in place. The U-bolt passes through the hole. The upper U-bolt washer is placed between the photovoltaic module and the secondary purlin. The lower U-bolt washer is placed under the secondary purlin. The U-bolt passes through the upper and lower U-bolt washers and extends beyond the secondary purlin. It is fixed by the U-bolt nut.

6. The novel hybrid pile rigid-flexible self-balancing marine photovoltaic system according to claim 1, characterized in that: The system includes a first support and a second support. The first support includes a cable tray, clamps, and support fixing rods. The support fixing rods are connected between two clamps, and cable trays are laid on the support fixing rods. The second support includes an inverter platform and clamps. An inverter fixing rod is set on the inverter platform, and the inverter platform is connected to four clamps. The clamps are fixed to the web members of the grid structure.

7. A novel hybrid pile-based rigid-flexible self-balancing offshore photovoltaic system, characterized in that, The construction method includes the following steps: S1: The hybrid piles are manufactured as a whole in the prefabrication plant, and then transported to the construction site by barge. The piles are then positioned using a positioning system and finally driven to the design elevation. S2: Offshore photovoltaic platform manufacturing: Onshore construction involves assembling the upper chord, web members, lower chord, bolted ball joints, and pile heads of the space frame. Prestressed steel strand bolts are then fixed to the bolted ball joints, holes are drilled at the steel strand sleeve positions, and prestressing is performed to complete the structural assembly of the entire platform. Subsequently, the main purlins, secondary purlins, photovoltaic modules, supports, and inverters are installed sequentially. Finally, anti-corrosion work is carried out at the bolted ball joint positions, completing the manufacturing of the offshore photovoltaic platform. S3: Offshore photovoltaic platform transportation: The manufactured offshore photovoltaic platform is hoisted onto the transport barge by the crane at the dock. The barge is equipped with transport fixtures to stack two offshore photovoltaic platforms together and transport them to the construction site. S4: Installation of offshore photovoltaic platform: The offshore photovoltaic platform is hoisted onto the pile foundation by slings. The lower sling is tied to the bolt ball joint between the upper chord of the grid frame. The four pins under the platform are inserted into the pile. Construction workers can weld the pin round plates to the pile end plates on site at the bolt ball position. S5: Connect the cables between the various offshore photovoltaic platforms after installation, and lay the cables between the photovoltaic module modules along the cable tray; the total cables are connected to the box-type transformer to complete the installation of the offshore photovoltaic power plant.

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