CN-122020934-A - Wave-reducing type offshore photovoltaic array based on wave reflection principle and design method

CN122020934ACN 122020934 ACN122020934 ACN 122020934ACN-122020934-A

Abstract

The invention discloses a wave-reducing type offshore photovoltaic array and a design method based on a wave reflection principle, belongs to the technical field of renewable energy development, and aims to set a target wave period range, establish a cylindrical buoy array frequency domain hydrodynamic model, calculate wave transmission indexes of different parameter combinations in the target wave period range, determine candidate parameter combinations according to the wave transmission indexes, establish a structure finite element model of a reflecting unit group based on the candidate parameter combinations, perform strength check, establish a coupling dynamics model of an array structure and a mooring system, calculate motion response and mooring stress, judge based on preset criteria, and output a buoy array parameter combination of the reflecting unit group meeting requirements.

Inventors

YE XIANGJI
QIAO DONGSHENG
ZHU CAIBAO
ZHAO XIN
JI ZEZHOU
WANG JIAN
CHI HAI

Assignees

中交第一航务工程勘察设计院有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. The design method of the wave-reducing type offshore photovoltaic array based on the wave reflection principle is characterized by comprising the following steps of: Acquiring wave spectrum data of a sea area to be built, determining a peak period, and setting a target wave period range based on the peak period; Setting at least one circle of photovoltaic array monomers arranged along the periphery of the array as a reflection unit group, and setting the photovoltaic array monomers positioned in the inner area of the array as a protected unit group; establishing a cylindrical pontoon array frequency domain hydrodynamic model corresponding to the reflecting unit group, calculating wave transmission indexes of different parameter combinations in the target wave period range by taking the pontoon number, pontoon spacing and pontoon size of the reflecting unit group as design variables, and determining candidate parameter combinations according to the wave transmission indexes; establishing a structural finite element model of the reflection unit group based on the candidate parameter combination and performing intensity check; Establishing a coupling dynamics model of the array structure and the mooring system, calculating the motion response and mooring stress of the array structure, and judging based on a preset criterion; When the equivalent stress calculated by the reflecting unit group in the strength check exceeds the allowable stress of the material or the preset criterion is not met in the coupling dynamics model, adjusting the design variable, and repeating the calculation and the judgment until the reflecting unit group pontoon array parameter combination meeting the requirement is output; The protected unit group adopts a preset reference pontoon array parameter combination, and the reflecting unit group pontoon array parameter combination and the reference pontoon array parameter are different in at least one of the pontoon number, the pontoon spacing and the pontoon size.
2. The method of claim 1, wherein the reference pontoon array parameter set is predetermined based on buoyancy and displacement requirements of the protected cell stack and the structural strength of the protected cell stack is lower than the structural strength of the reflective cell stack by at least one of reducing the number of cylindrical pontoons, reducing the size of the cylindrical pontoons, and reducing the wall thickness and/or cross-sectional dimensions of the upper frame members.
3. The design method of claim 2, wherein the structural finite element model of the protected unit group is built based on the reference pontoon array parameter combination and strength check is performed, and when the equivalent stress calculated by the protected unit group in the strength check exceeds the material allowable stress, the reference pontoon array parameter combination is adjusted and the strength check is repeated until the equivalent stress of the protected unit group does not exceed the material allowable stress.
4. The method of claim 1, wherein the set of reflective units comprises at least two circles of peripheral photovoltaic array units sequentially arranged from outside to inside along the periphery of the array, and the corresponding sets of reflective unit sets of pontoon array parameter combinations are determined for different circle layers respectively, such that the sets of reflective unit sets of pontoon array parameter combinations corresponding to different circle layers differ in at least one of pontoon number, pontoon spacing, and pontoon size.
5. The method of claim 1, wherein the wave transmission index comprises an average transmission index over the target wave period, the average transmission index being an index obtained by averaging transmission coefficients over the target wave period.
6. The method of claim 1, wherein when determining the candidate parameter set, performing preliminary screening on the pontoon pitch by using a quasi-notch condition so that the pontoon pitch L satisfies a relation of kl=npi within a predetermined error range, wherein k is a wave number corresponding to a target wave period, and n is a positive integer.
7. The design method according to claim 1, wherein the preset criteria comprises at least one of: The maximum tension of the mooring element does not exceed the allowable tension; the maximum stress of the connecting part does not exceed the allowable value; the equivalent stress of the reflective unit group and/or the protected unit group does not exceed the material allowable stress.
8. The method of claim 1, wherein after the predetermined criteria are satisfied, a unified array model is created without the differential parameters of the set of reflective units, wherein the set of reflective units and the set of protected units employ the same array parameters of pontoons, and the motion response and/or mooring forces are compared under the same environmental load conditions to verify the effectiveness of wave reduction.
9. The wave-reducing type offshore photovoltaic array based on the wave reflection principle is characterized in that the array structure is an array structure which is constructed by determining parameters by adopting the design method according to any one of claims 1-8, and comprises a plurality of photovoltaic array monomers which are arranged on a water surface in a preset array mode to form an array; at least one circle of photovoltaic array monomers arranged along the periphery of the array form a reflecting unit group, and the photovoltaic array monomers positioned in the inner area of the array form a protected unit group; Each photovoltaic array unit comprises a plurality of cylindrical pontoons, supporting piles connected with the cylindrical pontoons, an upper frame connected with the supporting piles and a photovoltaic assembly arranged on the upper frame; The array structure further comprises a mooring system for positioning constraints on the array structure.
10. The wave-reducing offshore photovoltaic array based on the wave reflection principle of claim 9, wherein the reflection unit group comprises at least two circles of peripheral photovoltaic array units sequentially arranged from outside to inside along the periphery of the array, and pontoon array parameter combinations of the reflection unit groups corresponding to the peripheral photovoltaic array units of different circles are different in at least one of pontoon number, pontoon spacing and pontoon size.

Description

Wave-reducing type offshore photovoltaic array based on wave reflection principle and design method Technical Field The invention belongs to the technical field of renewable energy development, and particularly relates to a wave-reducing type offshore photovoltaic array based on a wave reflection principle and a design method thereof. Background Compared with land photovoltaic and inland water photovoltaic, the offshore floating photovoltaic array has the advantages of land resource saving, wide and non-shielding sea area, strong complementation with offshore wind power and the like. However, the marine environment is complex, the long-term stable operation of the floating photovoltaic array faces the action of multi-source environmental loads such as waves, wind, flows and the like, wherein the wave loads often have significant influence on the motion response of the array, the stress of a connecting part and the tension of a mooring system, and further the structural safety and the material consumption are influenced. In the existing engineering design, one common scheme is unified structural design, namely, each photovoltaic array monomer in an array is subjected to unified design and material selection according to the less favorable environmental load working conditions which need to be resisted by the outside monomer. This approach, while convenient for design and verification, may overestimate the majority of the individual structural strength requirements of the array in the interior region, leading to increased material consumption and engineering costs. Another type of scheme is to arrange an independent breakwater or wave-dissipating device on the wave-facing side of the array or in the circumferential region of the array so as to reduce the influence of incident waves on the array, but the scheme generally requires additional engineering construction and maintenance investment, has high construction complexity and is easy to weaken the cost advantage of offshore photovoltaic. In addition, the existing offshore photovoltaic array design generally regards a buoyancy structure as a bearing and buoyancy providing unit, and the potential of wave reflection and scattering of the buoyancy structure under the arrayed arrangement condition cannot be fully utilized, so that it is difficult to effectively reduce wave transmission and reduce wave load in the array on the premise of not adding or only adding a few additional protective structures. Therefore, a technical scheme capable of reducing waves by utilizing the structural characteristics of the array and combining structural strength, mooring safety and engineering economy is needed. Disclosure of Invention The invention aims to provide a wave-reducing type offshore photovoltaic array based on a wave reflection principle and a design method thereof, so as to solve the problem that the existing offshore floating photovoltaic array depends on external wave-preventing/wave-eliminating facilities for reducing wave action, thereby causing higher engineering construction and operation and maintenance costs, and realize reduction of wave load in the array and improvement of structural economy on the basis. In order to achieve the above object, the present invention provides the following technical solutions: in a first aspect, the present invention provides a method for designing a wave-reducing offshore photovoltaic array based on the principle of wave reflection, comprising: Acquiring wave spectrum data of a sea area to be built, determining a peak period, and setting a target wave period range based on the peak period; Setting at least one circle of photovoltaic array monomers arranged along the periphery of the array as a reflection unit group, and setting the photovoltaic array monomers positioned in the inner area of the array as a protected unit group; establishing a cylindrical pontoon array frequency domain hydrodynamic model corresponding to the reflecting unit group, calculating wave transmission indexes of different parameter combinations in the target wave period range by taking the pontoon number, pontoon spacing and pontoon size of the reflecting unit group as design variables, and determining candidate parameter combinations according to the wave transmission indexes; establishing a structural finite element model of the reflection unit group based on the candidate parameter combination and performing intensity check; Establishing a coupling dynamics model of the array structure and the mooring system, calculating the motion response and mooring stress of the array structure, and judging based on a preset criterion; When the equivalent stress calculated by the reflecting unit group in the strength check exceeds the allowable stress of the material or the preset criterion is not met in the coupling dynamics model, adjusting the design variable, and repeating the calculation and the judgment until the reflecting unit group pontoon array parame