Stress gradient-based photovoltaic tracking support array partition optimization method and system

Abstract

This invention relates to the field of photovoltaic technology and provides a method and system for zoning optimization of photovoltaic tracking bracket arrays based on stress gradients. The method includes the following steps: constructing a load model, calculating the stress values ​​of each bracket in the photovoltaic tracking bracket array under different design conditions, and obtaining a full array stress distribution database; calculating and extracting the stress gradient characteristics of each bracket location, and combining the absolute stress level and location information of each bracket, using a clustering algorithm to divide the bracket array into multiple zones with different mechanical characteristics; for each zone with different mechanical characteristics, matching differentiated bracket component specifications that meet its design load and economic objectives from a pre-set modular bracket specification library. This invention, based on the full array stress distribution database and stress gradient characteristics, performs zoning optimization design, matching differentiated bracket component specifications that meet the design load for zones with different mechanical characteristics, resulting in better performance.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, specifically to a method and system for optimizing the partitioning of a photovoltaic tracking bracket array based on stress gradient. Background Technology

[0002] In the field of photovoltaic power generation, the application of photovoltaic tracking bracket arrays is becoming increasingly widespread. Photovoltaic tracking brackets can adjust the angle of photovoltaic modules in real time according to the sun's position, thereby significantly improving the power generation efficiency of photovoltaic systems. However, photovoltaic tracking bracket arrays are significantly affected by wind loads during actual operation, leading to varying degrees of stress on the brackets. The uneven distribution of this stress can have a significant impact on the structural safety and service life of the brackets.

[0003] Currently, in the design and selection of photovoltaic tracking bracket arrays, standardized bracket components are typically used to construct the entire array. While this design approach simplifies the design and construction process, it overlooks the actual load differences experienced by brackets at different locations. In reality, due to the varying locations of the brackets within the array, and the influence of factors such as shading and wind field distribution, their stress states differ significantly. For example, brackets at the array's edges may experience stronger wind impacts, resulting in higher stress levels and more dramatic stress variations; while brackets located in the core area of ​​the array experience relatively more uniform stress and lower stress levels.

[0004] Traditional uniform design methods cannot fully account for these stress differences, which may cause some supports to fail prematurely due to insufficient load-bearing capacity, affecting the normal operation of the entire photovoltaic system; while other supports may be over-designed, resulting in material waste and increased construction costs. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method and system for zoning optimization of photovoltaic tracking bracket array based on stress gradient, so as to solve the problems existing in the above-mentioned background technology.

[0006] This invention is implemented as follows: a method for partitioning and optimizing a photovoltaic tracking bracket array based on stress gradient, the method comprising the following steps: A load model was constructed to calculate the stress values ​​of each bracket in the photovoltaic tracking bracket array under different design conditions, and a database of stress distribution of the entire array was obtained. Based on the full array stress distribution database, the stress gradient features at each support location are calculated and extracted, and the stress gradient features include the stress gradient amplitude and the stress gradient direction. Based on stress gradient characteristics, combined with the absolute stress level and location information of each stent, a clustering algorithm is used to divide the stent array into multiple partitions with different mechanical characteristics. The partitions include at least a high stress gradient edge region, a low stress gradient core region, and a transition region between the two. For each zone with different mechanical characteristics, a differentiated support component specification that meets its design load and economic objectives is matched from a pre-set modular support specification library.

[0007] As a further aspect of the present invention, the step of constructing the load model specifically includes: Establish a three-dimensional wind field model of the photovoltaic site and obtain time history data of wind loads acting on each support position of the array under different wind direction angles and wind speed levels; A parametric finite element baseline model of the photovoltaic tracking bracket was established, and batch finite element calculations were performed based on the specific position of each bracket in the array and the corresponding wind load data. Extract and store the stress calculation results for each support part, including at least the bottom of the column, the mid-span of the main beam, and the diagonal brace connection node, to obtain a full-array stress distribution database containing spatial coordinates and multi-dimensional stress information.

[0008] As a further aspect of the present invention, the step of calculating and extracting the stress gradient characteristics at each support location specifically includes: Based on the full array stress distribution database, the rate of stress change at each support position in the row and column directions is calculated within the array plane. Based on the rate of change of stress in the row and column directions, the stress gradient amplitude at each support location is calculated, where the stress gradient amplitude is a scalar that measures the degree of drastic change in local stress space. Determine the stress gradient direction at each support location, whereby the stress gradient direction represents the spatial direction in which the local stress increases the most.

[0009] As a further aspect of the present invention, the step of dividing the support array into multiple partitions with different mechanical characteristics using a clustering algorithm specifically includes: Construct a multidimensional feature vector Xi for the i-th support position in the support array, Xi=[σi,Gi,θi,di], where σi is the normalized value of the stress at that position, Gi is the calculated stress gradient magnitude, θi is the stress gradient direction, and di is the normalized distance from that position to the nearest boundary of the array. The feature vector set of all stents is used as input, and the density-based DBSCAN clustering algorithm is used for processing; high-density regions are identified, and sample points with connected densities are grouped into the same cluster to form the initial mechanical feature partitions. The initial partitions generated are adjusted for engineering applicability, the design control parameters of the partitions are calculated, and the category to which the partitions belong is determined based on the design control parameters.

[0010] As a further aspect of the present invention, the step of matching differentiated support component specifications that meet the design load and economic objectives for each partition specifically includes: Determine the design representative load for each zone and configure differentiated safety factors for zones with different risk levels; With the goal of minimizing the total material cost of each zone, and with strength, stiffness, and stability as constraints, the optimal combination of component specifications is matched from the support specification library for each zone. At the junction of different specification zones, at least one transition structure is designed, which includes setting a buffer row support of intermediate specification or locally reinforcing the connection node.

[0011] As a further aspect of the present invention, the modular support specification library includes load-bearing components, corresponding load-bearing performance parameters, and economic parameters.

[0012] Another object of the present invention is to provide a photovoltaic tracking bracket array partitioning optimization system based on stress gradient, the system comprising: The full array stress distribution module is used to build a load model, calculate the stress value of each bracket in the photovoltaic tracking bracket array under different design conditions, and obtain a full array stress distribution database. The stress gradient feature module is used to calculate and extract the stress gradient features at each support location based on the full array stress distribution database. The stress gradient features include the stress gradient amplitude and the stress gradient direction. The support array partitioning module is used to divide the support array into multiple partitions with different mechanical characteristics based on stress gradient characteristics and combined with the absolute stress level and location information of each support using a clustering algorithm. The partitions include at least a high stress gradient edge region, a low stress gradient core region, and a transition region located between the two. The support component configuration module is used to match different support component specifications that meet the design load and economic objectives for each zone with different mechanical characteristics from a preset modular support specification library.

[0013] Compared with the prior art, the beneficial effects of the present invention are: This invention constructs a load model to calculate a database of stress distribution across the entire array and extracts stress gradient features, enabling an accurate understanding of the actual stress state of each support. Based on this, a zoned optimization design is performed, matching differentiated support component specifications to zones with different mechanical characteristics to meet design loads. This ensures that each support operates within a safe stress range, effectively reducing the risk of support damage due to insufficient load-bearing capacity and improving the structural safety of the entire photovoltaic tracking support array. Furthermore, it avoids the over-design problem caused by uniform specifications, selecting appropriate support component specifications based on the actual stress requirements of different zones, reducing material waste and lowering construction costs. Attached Figure Description

[0014] Figure 1 This is a flowchart of a photovoltaic tracking bracket array partitioning optimization method based on stress gradient.

[0015] Figure 2 This is a flowchart illustrating the construction of a load model in a stress gradient-based photovoltaic tracking bracket array partitioning optimization method.

[0016] Figure 3 This is a flowchart illustrating the partitioning of the photovoltaic tracking bracket array in a stress gradient-based optimization method.

[0017] Figure 4 This is a flowchart illustrating the partitioning of the photovoltaic tracking support array according to different mechanical characteristics in a stress gradient-based photovoltaic support array partitioning optimization method.

[0018] Figure 5 This is a flowchart of the matching bracket components in the stress gradient-based photovoltaic tracking bracket array partitioning optimization method.

[0019] Figure 6 This is a schematic diagram of a photovoltaic tracking bracket array partitioning optimization system based on stress gradient. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0022] like Figure 1 As shown in the figure, this embodiment of the invention provides a method for zoning optimization of a photovoltaic tracking bracket array based on stress gradient. The method includes the following steps: S100, construct a load model, calculate the stress values ​​of key parts of each bracket in the photovoltaic tracking bracket array under different design conditions, and obtain a stress distribution database of the entire array; S200, based on the full array stress distribution database, calculate and extract the stress gradient features at each support location, the stress gradient features including stress gradient amplitude and stress gradient direction; S300, based on stress gradient characteristics and combined with the absolute stress level and location information of each support, uses a clustering algorithm to divide the support array into multiple partitions with different mechanical characteristics. The partition includes at least a high stress gradient edge region, a low stress gradient core region, and a transition region between the two. S400, for the different mechanical characteristic zones, matches the differentiated support component specifications that meet the design load and economic objectives for each zone from the preset modular support specification library.

[0023] It should be noted that existing technologies use uniformly sized bracket components to construct photovoltaic tracking bracket arrays, failing to consider the stress differences caused by varying environments at different locations within the array. This makes it impossible to design brackets with different stress states. Furthermore, existing technologies lack scientific stress analysis methods for rationally partitioning the photovoltaic tracking bracket array, making it impossible to match the most suitable bracket component specifications to different partitions, thus hindering the comprehensive optimization of structural safety and economy. The embodiments of this invention aim to solve the above problems.

[0024] In this embodiment of the invention, a three-dimensional wind field load model of the entire photovoltaic field area is first established by combining computational fluid dynamics (CFD) simulation with wind tunnel test data. The influence of local factors such as terrain undulation, surrounding buildings, and vegetation on the wind field is considered. Wind pressure distribution under different wind angles (0°-360°) and different wind speed levels (including extreme conditions) is simulated to obtain stress values ​​of key components of each support in the photovoltaic tracking support array under different design conditions, resulting in a full-array stress distribution database. Then, based on the full-array stress distribution database, the stress gradient characteristics of each support location are calculated and extracted. These stress gradient characteristics include stress gradient amplitude and stress gradient direction. The stress gradient amplitude is a scalar measuring the drastic degree of local stress spatial change, and the stress gradient direction represents the spatial direction of the fastest local stress growth. The establishment of the full-array stress distribution database and the extraction of stress gradient characteristics provide designers with comprehensive and accurate data support, making the design process more efficient and precise. Designers can quickly select appropriate support component specifications according to the characteristics of different zones, shortening the design cycle and improving design efficiency. Next, based on the stress gradient characteristics and combined with the absolute stress level and location information of each support, a clustering algorithm is used to divide the support array into multiple partitions with different mechanical characteristics. This partitioning method is scientific and objective, accurately identifying partitions with different mechanical characteristics, providing a reliable basis for subsequent differentiated design. Finally, for each partition with different mechanical characteristics, a differentiated support component specification that meets its design load and economic objectives is matched from a pre-set modular support specification library. This modular support specification library includes load-bearing components, corresponding load-bearing performance parameters, and economic parameters.

[0025] This invention constructs a load model to calculate a database of stress distribution across the entire array and extracts stress gradient features, enabling an accurate understanding of the actual stress state of each support. Based on this, a zoned optimization design is performed, matching differentiated support component specifications to different mechanical characteristic zones to meet design loads. This ensures that each support operates within a safe stress range, effectively reducing the risk of support damage due to insufficient load-bearing capacity and improving the structural safety of the entire photovoltaic tracking support array. Furthermore, it avoids the over-design problem caused by uniform specifications, selecting appropriate support component specifications based on the actual stress requirements of different zones, reducing material waste and construction costs. Simultaneously, the extended service life of the supports reduces maintenance and replacement costs, further improving the project's economic benefits.

[0026] like Figure 2 As shown, in a preferred embodiment of the present invention, the step of constructing the load model specifically includes: S101, Establish a three-dimensional wind field model of the photovoltaic site and obtain time history data of wind load acting on each support position of the array under different wind direction angles and wind speed levels; S102, Establish a parameterized finite element reference model for the photovoltaic tracking bracket, and perform batch finite element calculations based on the specific position of each bracket in the array and the corresponding wind load data; S103 Extract and store the stress calculation results of key parts of each support. The key parts include at least the bottom of the column, the mid-span of the main beam, and the connection node of the diagonal brace, to obtain a full-array stress distribution database containing spatial coordinates and multi-dimensional stress information.

[0027] Specifically, a three-dimensional wind field model of the photovoltaic site is established, and time history data of wind loads acting on each support location of the array under different wind direction angles and wind speed levels are obtained. The specific steps are as follows: Geographic information data and surface feature data are obtained through a three-dimensional wind field model of the photovoltaic site; using the elevation points, contour lines and obstacle boundaries in the geographic information data and surface feature data, a three-dimensional solid model of the photovoltaic site is constructed in a three-dimensional model environment. Based on the three-dimensional wind field model, the wind speed level standard and the coverage wind direction angle range are preset; based on the preset wind speed level standard and the coverage wind direction angle range, the different wind direction angles and wind speed levels to be simulated are determined; the three-dimensional solid model of the photovoltaic site is used as the calculation domain, and the inlet wind speed boundary conditions are defined for the wind speed level and wind direction angle using the wind speed level standard and the coverage wind direction angle range, so as to generate the working condition three-dimensional wind field model. The calculation accuracy parameters are determined based on the three-dimensional wind field model of the photovoltaic site; within the calculation domain of the three-dimensional wind field model under operating conditions, the calculation units are divided according to the calculation accuracy parameters, a discretized grid is generated, and a discretized three-dimensional wind field model is obtained. The Reynolds-averaged Navier-Stokes equations are used to process the discretized three-dimensional wind field model to calculate the stable wind speed and wind pressure values ​​at each spatial grid node in the spatially discretized three-dimensional wind field model, thereby obtaining the wind field distribution data of the entire field. The preset support layout scheme is obtained based on the support location; based on the wind field distribution data of the whole field and combined with the preset support layout scheme, the row and column coordinates of each support in the array are obtained; through the row and column coordinates of each support in the array, the corresponding stable wind speed and wind pressure values ​​are extracted from the wind field distribution data of the whole field to obtain the wind load dataset. Wind load coefficient and wind vibration coefficient are obtained from wind load time history data; wind load coefficient and wind vibration coefficient are used to convert wind pressure data at each location and under each working condition in the wind load data into wind load time history data of support nodes. Based on the wind direction angle, wind speed level, and the row and column coordinates of the support in the array, the wind load time history data of the support node are sorted and integrated to obtain the wind load time history data acting on each support position of the array under different wind direction angles and wind speed levels.

[0028] Furthermore, this invention achieves high-precision and dynamic extraction of wind loads at various support locations of the photovoltaic array by comprehensively considering terrain, surface features, and various wind directions and speeds through refined three-dimensional wind field simulation. This provides a real and reliable load basis for subsequent stress analysis and zoning optimization, and improves the accuracy and safety of structural design.

[0029] In this embodiment of the invention, wind load time history data for each support location is obtained by simulating wind pressure distribution under different wind angles and wind speed levels. A parametric finite element model of the tracking support, containing all structural details including columns, beams, braces, and the drive system, needs to be established. Combining the specific location of each support in the array with the corresponding wind load data, batch finite element calculations are performed to obtain the stress distribution of key components, including: bending moment and axial force at the bottom of the column, maximum stress at the mid-span of the main beam, stress concentration factor at the brace connection point, and reaction force at the drive system support point. Finally, the stress calculation results for each support are structured and stored, including key parameters such as maximum stress value, stress amplitude, and stress cycle characteristics, resulting in a full-array stress distribution database containing spatial coordinates and multi-dimensional stress information.

[0030] like Figure 3 As shown in the preferred embodiment of the present invention, the step of calculating and extracting the stress gradient characteristics at each support location specifically includes: S201, Based on the full array stress distribution database, calculate the stress change rate of each support position in the row and column directions within the array plane; S202, calculate the stress gradient amplitude at each support location based on the stress change rate in the row and column directions, where the stress gradient amplitude is a scalar that measures the degree of drastic change in local stress space; S203, determine the stress gradient direction at each support location, wherein the stress gradient direction represents the spatial direction in which the local stress increases the fastest.

[0031] Specifically, based on the full array stress distribution database, the stress change rate at each support location in the row and column directions is calculated within the array plane. The specific steps are as follows: Based on spatial coordinates, the coordinates of adjacent supports in the row and column directions of the current support are identified from the full array stress distribution database; the coordinates of adjacent supports in the row and column directions of the current support include the coordinates of four adjacent supports. Based on the coordinates of the current support in the row and column directions of the adjacent supports, the stress values ​​of the parts are extracted from the full array stress distribution database to obtain the set of stress values ​​of the parts; Obtain the stress value of the current support, the stress value of the adjacent support in the row direction, and the stress value of the adjacent support in the column direction from the set of stress values ​​of the current support. Subtract the stress value of the current support from the stress values ​​of the adjacent supports in the two row directions to obtain the local stress difference in the first row direction and the local stress difference in the second row direction. Subtract the stress value of the current support from the stress values ​​of the adjacent supports in the two column directions to obtain the local stress difference in the first column direction and the local stress difference in the second column direction. By using spatial coordinates, the actual straight-line distance between the current support and the adjacent support is determined, and the actual spacing value is obtained; The stress variation rate in the first row direction and the stress variation rate in the second row direction are obtained by dividing the local stress difference in the first row direction and the local stress difference in the second row direction by the actual spacing, respectively; the stress variation rate in the first column direction and the stress variation rate in the second column direction are obtained by dividing the local stress difference in the first column direction and the local stress difference in the second column direction by the actual spacing, respectively.

[0032] Furthermore, by quantifying the stress difference between each support and its adjacent supports, and calculating the rate of change of stress in the row and column directions based on the actual spatial distance, this invention accurately captures the spatial distribution law and trend of stress within the array, providing a precise and reliable local mechanical characteristic data basis for subsequent scientific zoning and differentiated design based on stress gradient.

[0033] In this embodiment of the invention, the central difference method is used to calculate the rate of stress change at each support location. Then, based on the rate of stress change in the row and column directions, the stress gradient amplitude at each support location is calculated. Next, the dominant direction of the gradient vector is statistically analyzed to identify the sensitive direction of stress change, thereby determining the stress gradient direction.

[0034] like Figure 4 As shown, in a preferred embodiment of the present invention, the step of dividing the support array into multiple partitions with different mechanical characteristics using a clustering algorithm specifically includes: S301, construct a multidimensional feature vector Xi for the i-th support position in the support array, Xi=[σi, Gi, θi, di], where σi is the normalized value of the stress in the key part of the position, Gi is the calculated stress gradient magnitude, θi is the stress gradient direction, and di is the normalized distance from the position to the nearest boundary of the array. S302 takes the feature vector set of all stents as input and processes it using the density-based DBSCAN clustering algorithm; it identifies high-density regions and groups sample points with connected densities into the same cluster to form the initial mechanical feature partitioning. S303, adjust the engineering applicability of the generated initial partition, calculate the design control parameters of the partition, and determine the category of the partition based on the design control parameters.

[0035] Specifically, the feature vector set of all stents is used as input, and the density-based DBSCAN clustering algorithm is used for processing; high-density regions are identified, and sample points with connected densities are grouped into the same cluster to form the initial mechanical feature partitions. The specific steps are as follows: The normalized stress value, stress gradient magnitude, stress gradient direction, and normalized distance are obtained by summarizing the feature vector set of the support to obtain the initial setting parameters; Based on the initial setting parameters, the normalized value of stress, the magnitude of stress gradient, the difference between each pair of stress gradient direction and normalized distance are calculated to obtain the setting parameter difference; based on the setting parameter difference, the scalar value is calculated using the Euclidean norm. The DBSCAN clustering algorithm is used to preset the neighborhood radius parameter; scalar values ​​are compared with the preset neighborhood radius parameter, and scaffolds corresponding to scalar values ​​smaller than the preset neighborhood radius parameter are selected to obtain the core point set; Starting with the scaffolds in the core point set, all scaffolds within the neighborhood of the starting point are retrieved according to the preset neighborhood radius parameter. If other core points are found during the retrieval process, they are merged into the current set and used as a new starting point. The core cluster is then recursively expanded from the new starting point. The set of noise points is obtained by statistically analyzing the supports that do not belong to the core cluster. All elements in the noise point set are mapped back to the corresponding support coordinates, and the support coordinates are grouped to obtain the initial mechanical feature partitions.

[0036] Furthermore, the density-based clustering algorithm of this invention automatically and objectively groups supports with similar stress and gradient characteristics into the same mechanical partition, without the need to pre-specify the number of partitions. It can also effectively identify dense areas of arbitrary shapes and separate discrete outliers, thereby providing a reliable and engineering-practical partitioning basis for subsequent differentiated and precise support selection and optimization design.

[0037] In this embodiment of the invention, a multi-dimensional feature vector is constructed for each support position in the support array. Specifically, the multi-dimensional feature vector includes the normalized value of the stress at the key location, the stress gradient magnitude, the stress gradient direction, and the normalized distance from that location to the nearest boundary of the array. Then, the DBSCAN clustering algorithm is used to divide the region based on the density reachability principle. The advantages of this algorithm are: it does not require pre-specifying the number of partitions, it can identify regions of arbitrary shapes, and it automatically eliminates noise points. The algorithm can automatically identify high-density regions and group densely connected sample points into the same cluster, forming initial mechanical feature partitions, while marking sample points in sparse regions as noise points. Then, the initial partitions generated by the algorithm are adjusted for engineering applicability, including: 1. Merging isolated small partitions with areas smaller than a preset threshold into the adjacent main partitions with the most similar mechanical features; 2. Smoothing the partition boundaries to align them as closely as possible with the row and column directions of the array or existing channels in the field to facilitate construction; 3. Establishing a clear transition zone with a buffering effect between adjacent partitions with significant differences in stress levels or gradient characteristics. Finally, the design control parameters of the partition are calculated. The design control parameters include the statistical representative value of the support stress in the partition and the average stress gradient of the partition. Based on the design control parameters, the category of the partition is determined, which is either a high stress gradient edge zone, a low stress gradient core zone, or a transition zone.

[0038] like Figure 5 As shown, in a preferred embodiment of the present invention, the step of matching differentiated support component specifications that meet the design load and economic objectives for each zone specifically includes: S401, determine the design representative load for each zone and configure differentiated safety factors for zones with different risk levels; S402 aims to minimize the total material cost of each zone, while taking strength, stiffness, and stability as constraints. It matches the optimal combination of component specifications from the support specification library for each zone. S403, at the junction of different specification zones, at least one transition structure is designed, the transition structure including setting a buffer row support of intermediate specification, or locally reinforcing the connection node.

[0039] Specifically, with the goal of minimizing the total material cost of each zone, and with strength, stiffness, and stability as constraints, the optimal combination of component specifications is matched from the support specification library for each zone. The specific steps are as follows: Using the full array distributed database, extract the stress values ​​of all supports in the same zone; multiply the highest stress value of the zone by the safety factor to obtain the control load value of the zone. Obtain the load-bearing capacity parameters of each specification from the modular support specification library; compare the control load value of each zone with the load-bearing capacity parameters, and filter out the specifications corresponding to the load-bearing capacity parameters that are greater than the control load value of the zone to obtain a preliminary set of support component specifications; The stiffness parameters of each specification are obtained from the modular support specification library. Based on the stiffness parameters, the initial set of support component specifications is evaluated to determine whether the stiffness of the support components in the initial set of support component specifications meets the stiffness constraint requirements. Support component specifications that exceed the range of stiffness parameters are removed to obtain the secondary set of support component specifications. The stability parameters of each specification are obtained from the modular support specification library; the stability parameters are used to evaluate the secondary set of support component specifications to determine whether the support components in the secondary set of support component specifications meet the stability constraints, and support component specifications that exceed the range of stability parameters are removed to obtain a candidate set of support component specifications. Traverse the candidate set of bracket component specifications and extract the economic parameters corresponding to each specification from the modular bracket specification library; combine the total number of brackets in each partition to calculate the total material cost corresponding to each specification in the candidate set of bracket component specifications and obtain the total material cost data. With the goal of minimizing total material cost, the total material cost data is compared, and the specification with the lowest total material cost is selected as the initial optimal solution for each partition, thus obtaining the optimal combination of component specifications for each partition.

[0040] Furthermore, this busy process involves screening candidate specifications that meet the constraints of load-bearing capacity, stiffness, and stability at each level, and optimizing the selection with the ultimate goal of minimizing the total material cost of each zone. Under the premise of ensuring the structural safety and reliability of each zone, the economic efficiency of modular components is maximized, thereby achieving scientific control and reduction of the overall construction cost of the photovoltaic support array.

[0041] In this embodiment of the invention, the specification library contains a series of columns, main beams, diagonal braces, and connectors with various strength and stiffness grades. The "statistical high value" of all support loads within a zone is used to represent the design load of the entire zone, and differentiated safety factors are configured for zones with different risk levels; the higher the risk, the larger the safety factor; the lower the risk, the lower the safety factor can be appropriately optimized to achieve a balance between safety and economy. Then, with the goal of minimizing the total material cost of the zone, and with strength, stiffness, and stability as constraints, the optimal combination of component specifications is matched from the support specification library for each zone. Furthermore, at the boundaries between zones of different specifications, transition structures are designed. These transition structures can be buffer rows of intermediate-specification supports or local reinforcement of connection nodes.

[0042] like Figure 6 As shown, this embodiment of the invention also provides a photovoltaic tracking bracket array partitioning optimization system based on stress gradient, the system comprising: The full array stress distribution module 100 is used to build a load model, calculate the stress values ​​of key parts of each bracket in the photovoltaic tracking bracket array under different design conditions, and obtain a full array stress distribution database. The stress gradient feature module 200 is used to calculate and extract the stress gradient features of each support position based on the full array stress distribution database. The stress gradient features include the stress gradient amplitude and the stress gradient direction. The support array partitioning module 300 is used to divide the support array into multiple partitions with different mechanical characteristics based on stress gradient characteristics and combined with the absolute stress level and location information of each support using a clustering algorithm. The partitions include at least a high stress gradient edge region, a low stress gradient core region, and a transition region located between the two. The support component configuration module 400 is used to match different support component specifications that meet the design load and economic objectives for each partition with different mechanical characteristics from a preset modular support specification library.

[0043] In a preferred embodiment of the present invention, the full array stress distribution module 100 includes: The wind load data acquisition unit is used to establish a three-dimensional wind field model of the photovoltaic site and acquire time history data of wind loads acting on each support position of the array under different wind direction angles and wind speed levels. The finite element calculation unit is used to establish a parameterized finite element reference model of the photovoltaic tracking bracket, and to perform batch finite element calculations based on the specific position of each bracket in the array and the corresponding wind load data. The stress distribution database unit is used to extract and store the stress calculation results of key parts of each support. The key parts include at least the bottom of the column, the mid-span of the main beam, and the connection node of the diagonal brace, so as to obtain a full array stress distribution database containing spatial coordinates and multi-dimensional stress information.

[0044] In a preferred embodiment of the present invention, the stress gradient feature module 200 includes: The stress change rate unit is used to calculate the stress change rate of each support position in the row and column directions within the array plane based on the full array stress distribution database. The stress gradient amplitude unit is used to calculate the stress gradient amplitude at each support location based on the rate of change of stress in the row and column directions. The stress gradient amplitude is a scalar that measures the degree of drastic change in local stress space. A stress gradient direction unit is used to determine the stress gradient direction at each support location, wherein the stress gradient direction represents the spatial direction in which the local stress increases the fastest.

[0045] In a preferred embodiment of the present invention, the bracket array partitioning module 300 includes: A multidimensional feature construction unit is used to construct a multidimensional feature vector Xi for the i-th support position in the support array, Xi=[σi, Gi, θi, di], where σi is the normalized value of the stress of the key part at the position, Gi is the calculated stress gradient magnitude, θi is the stress gradient direction, and di is the normalized distance from the position to the nearest boundary of the array. The initial partitioning unit takes the feature vector set of all scaffolds as input and processes it using the density-based DBSCAN clustering algorithm; it identifies high-density regions and groups sample points with connected densities into the same cluster to form the initial mechanical feature partitions. The partition category determination unit is used to adjust the engineering applicability of the generated initial partitions, calculate the design control parameters of the partitions, and determine the category to which the partitions belong based on the design control parameters.

[0046] The above description only details the preferred embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0047] It should be understood that although the steps in the flowcharts of the various embodiments of the present invention are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the various embodiments may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0048] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0049] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the disclosure in the specification and embodiments. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

Claims

1. A method for partitioning and optimizing photovoltaic tracking bracket arrays based on stress gradient, characterized in that, The method includes the following steps: A load model was constructed to calculate the stress values ​​of each bracket in the photovoltaic tracking bracket array under different design conditions, and a database of stress distribution of the entire array was obtained. Based on the full array stress distribution database, the stress gradient features at each support location are calculated and extracted, and the stress gradient features include the stress gradient amplitude and the stress gradient direction. Based on stress gradient characteristics, combined with the absolute stress level and location information of each stent, a clustering algorithm is used to divide the stent array into multiple partitions with different mechanical characteristics. The partitions include at least a high stress gradient edge region, a low stress gradient core region, and a transition region between the two. For each zone with different mechanical characteristics, a differentiated support component specification that meets its design load and economic objectives is matched from a pre-set modular support specification library.

2. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 1, characterized in that, The steps for constructing the load model specifically include: Establish a three-dimensional wind field model of the photovoltaic site and obtain time history data of wind loads acting on each support position of the array under different wind direction angles and wind speed levels; A parametric finite element baseline model of the photovoltaic tracking bracket was established, and batch finite element calculations were performed based on the specific position of each bracket in the array and the corresponding wind load data. Extract and store the stress calculation results for each support component, including at least the bottom of the column, the mid-span of the main beam, and the diagonal brace connection nodes, to obtain a full-array stress distribution database containing spatial coordinates and multi-dimensional stress information.

3. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 2, characterized in that, A three-dimensional wind field model of the photovoltaic site was established, and time history data of wind loads acting on each support location of the array under different wind direction angles and wind speed levels were obtained. The specific steps are as follows: Geographic information data and surface feature data are obtained through a three-dimensional wind field model of the photovoltaic site; using the elevation points, contour lines and obstacle boundaries in the geographic information data and surface feature data, a three-dimensional solid model of the photovoltaic site is constructed in a three-dimensional model environment. Based on the three-dimensional wind field model, preset wind speed level standards and coverage wind direction angle range; based on the preset wind speed level standards and coverage wind direction angle range, determine the different wind direction angles and wind speed levels that need to be simulated; Using the three-dimensional solid model of the photovoltaic site as the computational domain, and utilizing the wind speed level standard and the coverage wind direction angle range, the inlet wind speed boundary conditions are defined for the wind speed level and wind direction angle to generate the three-dimensional wind field model under the working condition. The calculation accuracy parameters are determined based on the three-dimensional wind field model of the photovoltaic site; Within the computational domain of the three-dimensional wind field model under working conditions, computational units are divided according to the computational accuracy parameters to generate a discretized grid and obtain a discretized three-dimensional wind field model. The Reynolds-averaged Navier-Stokes equations are used to process the discretized three-dimensional wind field model to calculate the stable wind speed and wind pressure values ​​at each spatial grid node in the spatially discretized three-dimensional wind field model, thereby obtaining the wind field distribution data of the entire field. A preset support layout scheme is obtained based on the support location; Based on the wind field distribution data of the entire field and combined with the preset support arrangement scheme, the row and column coordinates of each support in the array are obtained; by using the row and column coordinates of each support in the array, the corresponding stable wind speed and wind pressure values ​​are extracted from the wind field distribution data of the entire field to obtain the wind load dataset. Wind load coefficient and wind vibration coefficient are obtained from wind load time history data; wind load coefficient and wind vibration coefficient are used to convert wind pressure data at each location and under each working condition in the wind load data into wind load time history data of support nodes. Based on the wind direction angle, wind speed level, and the row and column coordinates of the support in the array, the wind load time history data of the support node are sorted and integrated to obtain the wind load time history data acting on each support position of the array under different wind direction angles and wind speed levels.

4. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 3, characterized in that, The step of calculating and extracting the stress gradient characteristics at each support location specifically includes: Based on the full array stress distribution database, the rate of stress change at each support position in the row and column directions is calculated within the array plane. Based on the rate of change of stress in the row and column directions, the stress gradient amplitude at each support location is calculated, where the stress gradient amplitude is a scalar that measures the degree of drastic change in local stress space. Determine the stress gradient direction at each support location, whereby the stress gradient direction represents the spatial direction in which the local stress increases the most.

5. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 4, characterized in that, Based on the full array stress distribution database, the stress change rate at each support location in the row and column directions is calculated within the array plane. The specific steps are as follows: Based on spatial coordinates, the coordinates of adjacent supports in the row and column directions of the current support are identified from the full array stress distribution database; the coordinates of adjacent supports in the row and column directions of the current support include the coordinates of four adjacent supports. Based on the coordinates of the current support in the row and column directions of the adjacent supports, the stress values ​​of the parts are extracted from the full array stress distribution database to obtain the set of stress values ​​of the parts; The stress values ​​of the current support, the stress values ​​of the adjacent supports in the row direction, and the stress values ​​of the adjacent supports in the column direction are obtained from the set of stress values ​​of the current support. Subtract the stress value of the current support from the stress values ​​of the adjacent supports in the two row directions to obtain the local stress difference in the first row direction and the local stress difference in the second row direction. Subtract the stress value of the current support from the stress values ​​of the adjacent supports in the two column directions to obtain the local stress difference in the first column direction and the local stress difference in the second column direction. By using spatial coordinates, the actual straight-line distance between the current support and the adjacent support is determined, and the actual spacing value is obtained; The stress variation rate in the first row direction and the stress variation rate in the second row direction are obtained by dividing the local stress difference in the first row direction and the local stress difference in the second row direction by the actual spacing, respectively; the stress variation rate in the first column direction and the stress variation rate in the second column direction are obtained by dividing the local stress difference in the first column direction and the local stress difference in the second column direction by the actual spacing, respectively.

6. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 5, characterized in that, The steps of dividing the support array into multiple partitions with different mechanical characteristics using a clustering algorithm specifically include: Construct a multidimensional feature vector Xi for the i-th support position in the support array, Xi=[σi,Gi,θi,di], where σi is the normalized value of the stress at that position, Gi is the calculated stress gradient magnitude, θi is the stress gradient direction, and di is the normalized distance from that position to the nearest boundary of the array. The feature vector set of all stents is used as input, and the density-based DBSCAN clustering algorithm is used for processing; high-density regions are identified, and sample points with connected densities are grouped into the same cluster to form the initial mechanical feature partitions. The initial partitions generated are adjusted for engineering applicability, the design control parameters of the partitions are calculated, and the category to which the partitions belong is determined based on the design control parameters.

7. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 6, characterized in that, The feature vector set of all scaffolds is used as input, and the density-based DBSCAN clustering algorithm is used for processing; high-density regions are identified, and sample points with connected densities are grouped into the same cluster to form the initial mechanical feature partitions. The specific steps are as follows: The normalized stress value, stress gradient magnitude, stress gradient direction, and normalized distance are obtained by summarizing the feature vector set of the support to obtain the initial setting parameters; Based on the initial setting parameters, calculate the normalized value of stress, the magnitude of stress gradient, the direction of stress gradient, and the numerical difference between each pair of normalized distances to obtain the setting parameter difference. Based on the set parameter difference, the scalar value is calculated using the Euclidean norm; Preset the neighborhood radius parameter using the DBSCAN clustering algorithm; The scalar value is compared with the preset domain radius parameter, and the scaffolds corresponding to the scalar values ​​that are smaller than the preset domain radius parameter are selected to obtain the core point set. Starting with the scaffolds in the core point set, all scaffolds within the neighborhood of the starting point are retrieved according to the preset neighborhood radius parameter. If other core points are found during the retrieval process, they are merged into the current set and used as a new starting point. The core cluster is then recursively expanded from the new starting point. By statistically analyzing the scaffolds that do not belong to the core cluster, a set of noise points is obtained. Map all elements in the noise point set back to their corresponding support coordinates, and group the support coordinates to obtain the initial mechanical feature partitions.

8. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 7, characterized in that, The steps for matching differentiated support component specifications for each zone that meet its design load and economic objectives include: Determine the design representative load for each zone and configure differentiated safety factors for zones with different risk levels; With the goal of minimizing the total material cost of each zone, and with strength, stiffness, and stability as constraints, the optimal combination of component specifications is matched from the support specification library for each zone. At the junction of different specification zones, at least one transition structure is designed, which includes setting a buffer row support of intermediate specification or locally reinforcing the connection node.

9. The photovoltaic tracking bracket array partitioning optimization method based on stress gradient according to claim 8, characterized in that, With the goal of minimizing the total material cost of each zone, and with strength, stiffness, and stability as constraints, the optimal combination of component specifications is matched from the support specification library for each zone. The specific steps are as follows: Using the full array distributed database, extract the stress values ​​of all supports in the same zone; multiply the highest stress value of the zone by the safety factor to obtain the control load value of the zone. Obtain the load-bearing capacity parameters for each specification from the modular support specification library; By comparing the control load value of the partition with the bearing capacity parameter, the specifications corresponding to the bearing capacity parameter being greater than the control load value of the partition are selected, thus obtaining a preliminary set of support component specifications. Obtain the stiffness parameters of each specification from the modular support specification library; Based on the stiffness parameters, the initial set of support component specifications is evaluated to determine whether the stiffness of the support components in the initial set of support component specifications meets the stiffness constraint requirements, and support component specifications that exceed the range of stiffness parameters are removed to obtain the secondary set of support component specifications. The stability parameters of each specification are obtained from the modular support specification library; the stability parameters are used to evaluate the secondary set of support component specifications to determine whether the support components in the secondary set of support component specifications meet the stability constraints, and support component specifications that exceed the range of stability parameters are removed to obtain a candidate set of support component specifications. Traverse the candidate set of support component specifications and extract the economic parameters corresponding to each specification from the modular support specification library; Based on the total number of brackets in each zone, calculate the total material cost corresponding to each specification in the candidate set of bracket component specifications to obtain the total material cost data; With the goal of minimizing total material cost, the total material cost data is compared, and the specification with the lowest total material cost is selected as the initial optimal solution for each partition, thus obtaining the optimal combination of component specifications for each partition.

10. A photovoltaic tracking bracket array zoning optimization system based on stress gradient, characterized in that, The system employs the stress gradient-based photovoltaic tracking bracket array partitioning optimization method as described in any one of claims 1 to 9 above, and the system comprises: The full array stress distribution module is used to build a load model, calculate the stress value of each bracket in the photovoltaic tracking bracket array under different design conditions, and obtain a full array stress distribution database. The stress gradient feature module is used to calculate and extract the stress gradient features at each support location based on the full array stress distribution database. The stress gradient features include the stress gradient amplitude and the stress gradient direction. The support array partitioning module is used to divide the support array into multiple partitions with different mechanical characteristics based on stress gradient characteristics and combined with the absolute stress level and location information of each support using a clustering algorithm. The partitions include at least a high stress gradient edge region, a low stress gradient core region, and a transition region located between the two. The support component configuration module is used to match different support component specifications that meet the design load and economic objectives for each zone with different mechanical characteristics from a preset modular support specification library.

11. The photovoltaic tracking bracket array partitioning optimization system based on stress gradient according to claim 10, characterized in that, The full-array stress distribution module includes: The wind load data acquisition unit is used to establish a three-dimensional wind field model of the photovoltaic site and acquire time history data of wind loads acting on each support position of the array under different wind direction angles and wind speed levels. The finite element calculation unit is used to establish a parameterized finite element reference model of the photovoltaic tracking bracket, and to perform batch finite element calculations based on the specific position of each bracket in the array and the corresponding wind load data. The stress distribution database unit is used to extract and store the stress calculation results of key parts of each support. The key parts include at least the bottom of the column, the mid-span of the main beam, and the connection node of the diagonal brace, so as to obtain a full array stress distribution database containing spatial coordinates and multi-dimensional stress information.

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