Pile foundation grounding structure design method and system

Abstract

The invention discloses a pile foundation grounding structure design method and system, and relates to the technical field of power system grounding, and the method comprises the steps: obtaining reference design parameters of a pile foundation grounding structure, and constructing a multi-physics field coupling simulation model through the reference design parameters; the multi-physics field coupling simulation model is adopted to conduct iterative optimization on the to-be-optimized design parameters of the pile foundation grounding structure, corresponding initial design parameters and target simulation parameters are obtained, the initial design parameters are verified according to the target simulation parameters and the multi-physics field coupling simulation model, and corresponding target design parameters are obtained. The technical problems that an existing pile foundation grounding structure mostly depends on an empirical formula or a simple static resistor for design, global optimal design is difficult to achieve, and the operation reliability of a power transmission line is reduced are solved.

Description

Technical Field

[0001] This invention relates to the field of power system grounding technology, and in particular to a design method and system for pile foundation grounding structures. Background Technology

[0002] With the continuous expansion of ultra-high voltage (UHV) transmission line construction, the line layout is extending into complex geological areas such as the southwestern mountainous regions, the northwestern Loess Plateau, and coastal tidal flats. These areas are generally characterized by high soil resistivity, strong soil corrosivity, and frequent and intense lightning activity, placing extremely stringent requirements on the reliability, stability, and durability of the pile foundation grounding structure of transmission line towers. As a core component of power system lightning protection, the performance of the pile foundation grounding structure directly affects the safe and stable operation of transmission lines. Poor grounding can easily lead to serious accidents such as equipment insulation breakdown and tower damage under transient high current impacts, thereby affecting the continuity of regional power supply. Therefore, there is an urgent need for pile foundation grounding structures adapted to complex geological environments.

[0003] Currently, existing pile foundation grounding structures mostly rely on empirical formulas or simple static resistance for design, lacking accurate simulation of transient electromagnetic-thermal coupling behavior, and there is no systematic multi-parameter collaborative optimization process for structural parameters, making it difficult to achieve globally optimal design and reducing the reliability of transmission line operation. Summary of the Invention

[0004] This invention provides a design method and system for pile foundation grounding structures, which solves the technical problems of existing pile foundation grounding structures relying on empirical formulas or simple static resistance for design, lacking accurate simulation of transient electromagnetic-thermal coupling behavior, and lacking a systematic multi-parameter collaborative optimization process for structural parameters, making it difficult to achieve global optimal design and reducing the reliability of transmission line operation.

[0005] The first aspect of this invention provides a design method for a pile foundation grounding structure, comprising:

[0006] Obtain the reference design parameters of the pile foundation grounding structure, and use the reference design parameters to construct a multiphysics coupling simulation model;

[0007] The multiphysics coupling simulation model is used to iteratively optimize the design parameters of the pile foundation grounding structure to obtain the corresponding initial design parameters and target simulation parameters.

[0008] The initial design parameters are verified based on the target simulation parameters and the multiphysics coupling simulation model to obtain the corresponding target design parameters.

[0009] Optionally, the step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupled simulation model to obtain the corresponding initial design parameters and target simulation parameters includes:

[0010] An initial optimization parameter population is constructed using the design parameters to be optimized for the pile foundation grounding structure as individuals;

[0011] The multiphysics coupling simulation model is updated using each of the design parameters to be optimized, resulting in multiple target multiphysics coupling simulation models;

[0012] A preset transient solver is used to perform coupled solution on each of the target multiphysics field coupled simulation models to obtain multiple surface potentials and multiple injected lightning current amplitudes;

[0013] The performance of each of the aforementioned surface potentials and each of the aforementioned injected lightning current amplitudes is evaluated to obtain multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices;

[0014] The initial optimization parameter population is iteratively optimized using each of the objective function values ​​to obtain the corresponding initial design parameters, and the impulse grounding resistance and uniformity index corresponding to the initial design parameters are used as target simulation parameters.

[0015] Optionally, the step of evaluating the performance of each of the surface potentials and each of the injected lightning current amplitudes to obtain multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices includes:

[0016] The maximum value among the surface potentials corresponding to each of the injected lightning current amplitudes is determined as the maximum surface potential.

[0017] The amplitude of each injected lightning current is compared with the corresponding maximum ground surface potential to obtain multiple impulse grounding resistances.

[0018] The surface potential corresponding to each of the injected lightning current amplitudes is input into a preset uniformity function to obtain multiple uniformity indices;

[0019] Based on preset evaluation weights, weighted calculations are performed on each of the aforementioned impulse grounding resistances and their corresponding uniformity indices to obtain multiple objective function values.

[0020] Optionally, the step of iteratively optimizing the initial optimization parameter population using each of the objective function values ​​to obtain the corresponding initial design parameters includes:

[0021] The initial optimization parameter population is updated based on each of the objective function values ​​to obtain a new initial optimization parameter population;

[0022] Determine whether the number of iterations of the initial optimization parameter population is greater than or equal to a preset iteration threshold;

[0023] When the number of iterations is less than the iteration threshold, the process jumps to the step of updating the multiphysics coupling simulation model with each of the design parameters to be optimized to obtain multiple target multiphysics coupling simulation models.

[0024] When the number of iterations is greater than or equal to the iteration threshold, the design parameter to be optimized corresponding to the minimum value among the objective function values ​​is selected as the initial design parameter.

[0025] Optionally, the step of verifying the initial design parameters based on the target simulation parameters and the multiphysics coupled simulation model to obtain the corresponding target design parameters includes:

[0026] A scaled-down model test was conducted using the initial design parameters to obtain the corresponding test parameters.

[0027] The target simulation parameters and the experimental parameters are input into a preset calibration function to obtain the corresponding first error value and second error value;

[0028] When the first error value or the second error value is greater than the preset error threshold, the model parameters of the multiphysics coupling simulation model are adjusted, and the process jumps to the step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupling simulation model to obtain the corresponding initial design parameters and target simulation parameters.

[0029] When both the first error value and the second error value are less than or equal to the error threshold, the initial design parameters are determined as the target design parameters.

[0030] Optionally, the design parameters to be optimized include the double helix pitch, the difference in double helix radius, the tile arc length, the controllable discharge gap, the ratio of interlayer contact area, and the spacing of the annular horizontal grounding electrode.

[0031] A second aspect of the present invention provides a pile foundation grounding structure design system, comprising:

[0032] A construction module is used to obtain the reference design parameters of the pile foundation grounding structure, and to construct a multiphysics coupling simulation model using the reference design parameters.

[0033] The optimization module is used to iteratively optimize the design parameters of the pile foundation grounding structure to be optimized using the multiphysics coupling simulation model, so as to obtain the corresponding initial design parameters and target simulation parameters.

[0034] The verification module is used to verify the initial design parameters based on the target simulation parameters and the multiphysics coupling simulation model, so as to obtain the corresponding target design parameters.

[0035] A third aspect of the present invention provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the pile foundation grounding structure design method described above.

[0036] The fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the pile foundation grounding structure design method as described above.

[0037] The fifth aspect of the present invention provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, wherein, when the program instructions are executed by a computer, the computer performs the pile foundation grounding structure design method as described above.

[0038] As can be seen from the above technical solutions, the present invention has the following advantages:

[0039] This invention obtains the baseline design parameters of the pile foundation grounding structure, constructs a multi-physics coupled simulation model using these parameters, and iteratively optimizes the design parameters of the pile foundation grounding structure using this model to obtain the corresponding initial design parameters and target simulation parameters. The initial design parameters are then verified based on the target simulation parameters and the multi-physics coupled simulation model to obtain the corresponding target design parameters. This overcomes the technical problem that existing pile foundation grounding structures often rely on empirical formulas or simple static resistance for design, making it difficult to achieve globally optimal design and reducing the reliability of transmission line operation. Compared with traditional pile foundation grounding structure design, this invention uses the baseline design parameters to construct a multi-physics coupled simulation model and then collaboratively optimizes the design parameters of the pile foundation grounding structure using this model to obtain the corresponding target design parameters. This maximizes the comprehensive performance of impulse grounding resistance and transient potential distribution, thereby improving the technical problem of transmission line operation reliability. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a flowchart illustrating the steps of a pile foundation grounding structure design method according to Embodiment 1 of the present invention.

[0042] Figure 2 This is a flowchart illustrating the steps of a pile foundation grounding structure design method according to Embodiment 2 of the present invention.

[0043] Figure 3 This is a schematic diagram of the double-helix external grounding structure provided in Embodiment 2 of the present invention;

[0044] Figure 4 This is a schematic diagram of the pile foundation grounding structure provided in Embodiment 2 of the present invention;

[0045] Figure 5 This is a schematic diagram of the lightning impulse current waveform provided in Embodiment 2 of the present invention;

[0046] Figure 6 This is a schematic diagram illustrating the change in impulse grounding resistance of the double-helix external grounding structure provided in Embodiment 2 of the present invention;

[0047] Figure 7 This is a schematic diagram illustrating the change in impulse grounding resistance of the pile foundation grounding structure provided in Embodiment 2 of the present invention;

[0048] Figure 8 This is a structural block diagram of a pile foundation grounding structure design system provided in Embodiment 3 of the present invention;

[0049] Figure 9 This is a structural block diagram of an electronic device provided in Embodiment 4 of the present invention;

[0050] exist Figure 3-4 middle:

[0051] 1. Pile foundation grounding structure; 2. Double helix external grounding structure; 3. Ring grounding grid; 4. Anchor bolts; 5. Tile components. Detailed Implementation

[0052] This invention provides a design method and system for pile foundation grounding structures, which addresses the technical problems of existing pile foundation grounding structures relying on empirical formulas or simple static resistance for design, lacking accurate simulation of transient electromagnetic-thermal coupling behavior, and lacking a systematic multi-parameter collaborative optimization process for structural parameters, making it difficult to achieve globally optimal design and reducing the reliability of transmission line operation.

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be noted that in the optional embodiments of the present invention, the object information and other related data involved require the permission or consent of the object when the embodiments of the present invention are applied to specific products or technologies, and the collection, use, and processing of related data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. That is to say, if the embodiments of the present invention involve data related to the object, it needs to be obtained with the authorization and consent of the object, the authorization and consent of the relevant departments, and in compliance with the relevant laws, regulations, and standards of the country and region. If personal information is involved in the embodiments, the acquisition of all personal information requires the consent of the individual. If sensitive information is involved, the separate consent of the information subject is required, and the embodiments also need to be implemented with the authorization and consent of the object.

[0054] Please see Figure 1 , Figure 1 This is a flowchart illustrating the steps of a pile foundation grounding structure design method provided in Embodiment 1 of the present invention.

[0055] This invention provides a design method for a pile foundation grounding structure, comprising:

[0056] Step 101: Obtain the reference design parameters of the pile foundation grounding structure, and use the reference design parameters to construct a multi-physics field coupled simulation model.

[0057] The benchmark design parameters refer to the geometric dimensions, material properties, soil environmental parameters, and lightning current benchmark indices of the pile foundation grounding structure.

[0058] In this embodiment of the invention, the reference design parameters of the pile foundation grounding structure are obtained, and a preset three-dimensional electromagnetic simulation software (i.e., ANSYS HFSS or COMSOL Multiphysics) is called to construct a corresponding multiphysics coupling simulation model based on the reference design parameters.

[0059] It should be noted that in the process of modeling the multiphysics coupling simulation model, the core components such as the double-helix low-inductance discharge layer, the three-dimensional layered multipath current dissipation network, the bridging interconnection system, and the U-shaped grounding down conductor are modeled parametrically according to their actual size and relative position. At the same time, the simulation environment of the layered soil and air domains is integrated, and each component is assigned corresponding material properties. The soil is set as a lossy medium, the outer boundary of the computational domain is set as a radiation boundary or a perfectly matched layer (PML), and a lumped port excitation is set at the top of the grounding down conductor. Potential observation points are arranged on the surface grid nodes around the grounding device to obtain the corresponding multiphysics coupling simulation model.

[0060] Step 102: Use a multiphysics coupled simulation model to iteratively optimize the design parameters of the pile foundation grounding structure to obtain the corresponding initial design parameters and target simulation parameters.

[0061] The target simulation parameters refer to the initial design parameters that are input into the multiphysics coupled simulation model for solution, resulting in the impulse grounding resistance and uniformity index.

[0062] In this embodiment of the invention, an initial optimization parameter population is constructed using individual design parameters to be optimized. These design parameters include the double-helix pitch, double-helix radius difference, tile arc length, controllable discharge gap, interlayer contact area ratio, annular horizontal grounding electrode spacing, number of annular horizontal grounding electrode layers, number of tiles, tile thickness, equivalent radius of the annular horizontal grounding electrode, copper alloy guide plate size, modular snap-fit ​​installation position deviation, and welding contact parameters between the grounding down conductor and the double-helix layer. The multiphysics coupling simulation model is updated using each of these design parameters to be optimized, resulting in multiple target multiphysics coupling simulation models. A preset transient solver is used to perform coupled solutions on each target multiphysics coupling simulation model, yielding multiple surface potentials and multiple injected lightning current amplitudes. Performance evaluations are performed on each surface potential and each injected lightning current amplitude, resulting in multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices. The initial optimization parameter population is iteratively optimized using each objective function value to obtain the corresponding initial design parameters. The impulse grounding resistance and uniformity index corresponding to the initial design parameters are then used as target simulation parameters.

[0063] In another embodiment, based on a preset objective function and a multiphysics coupled simulation model, a sequential quadratic programming (SQP) algorithm is used to iteratively optimize the design parameters to be optimized for the pile foundation grounding structure (i.e., an initial optimization parameter population is constructed using the design parameters to be optimized as individuals. The multiphysics coupled simulation model is updated using each design parameter to be optimized, resulting in multiple target multiphysics coupled simulation models. A preset transient solver is used to coupled and solve each target multiphysics coupled simulation model, resulting in multiple surface potentials and multiple injected lightning current amplitudes. The performance of each surface potential and each injected lightning current amplitude is evaluated, resulting in multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices. Then, based on the SQP algorithm, the initial optimization parameter population is iteratively optimized using each objective function value to obtain the corresponding initial design parameters, and the impulse grounding resistance and uniformity index corresponding to the initial design parameters are used as target simulation parameters), resulting in the corresponding initial design parameters and target simulation parameters.

[0064] It should be noted that the Sequential Quadratic Programming (SQP) algorithm is an efficient algorithm suitable for constrained nonlinear optimization problems. It approximates the original problem by constructing a quadratic programming subproblem in each iteration. Solving the subproblem yields the parameter update direction and step size (i.e., the search direction determines the direction of parameter optimization, and the step size controls the magnitude of each parameter update). It approaches the optimal solution with a second-order convergence speed and is suitable for multi-dimensional parameter collaborative optimization scenarios.

[0065] Step 103: Verify the initial design parameters based on the target simulation parameters and the multiphysics coupling simulation model to obtain the corresponding target design parameters.

[0066] In this embodiment of the invention, a scaled-down model consistent with the actual pile foundation grounding structure's function and structural characteristics is created by scaling the initial design parameters proportionally. A real lightning strike scenario is simulated on a professional experimental platform, and the impulse grounding resistance and uniformity index corresponding to the scaled-down model are obtained through precise measurements. The target simulation parameters and the experimentally obtained impulse grounding resistance and uniformity index are input into a preset calibration function to obtain the corresponding first and second error values. When either the first or second error value is greater than 10%, the model parameters of the multiphysics coupling simulation model are adjusted, and step 102 is performed. When both the first and second error values ​​are less than or equal to 10%, the initial design parameters are determined as the target design parameters.

[0067] In this embodiment of the invention, by obtaining the baseline design parameters of the pile foundation grounding structure, a multiphysics field coupled simulation model is constructed using the baseline design parameters. The multiphysics field coupled simulation model is then used to iteratively optimize the design parameters of the pile foundation grounding structure to be optimized, yielding the corresponding initial design parameters and target simulation parameters. The initial design parameters are then verified based on the target simulation parameters and the multiphysics field coupled simulation model to obtain the corresponding target design parameters. This overcomes the technical problem that existing pile foundation grounding structures often rely on empirical formulas or simple static resistance for design, making it difficult to achieve globally optimal design and reducing the reliability of transmission line operation. Compared with traditional pile foundation grounding structure design, this invention uses the baseline design parameters to construct a multiphysics field coupled simulation model, and then uses this model to collaboratively optimize the design parameters of the pile foundation grounding structure to obtain the corresponding target design parameters. This maximizes the comprehensive performance of impulse grounding resistance and transient potential distribution, improving the technical problem of transmission line operation reliability.

[0068] Please see Figure 2 , Figure 2 This is a flowchart illustrating the steps of a pile foundation grounding structure design method provided in Embodiment 2 of the present invention.

[0069] This invention provides a design method for a pile foundation grounding structure, comprising:

[0070] Step 201: Obtain the reference design parameters of the pile foundation grounding structure, and use the reference design parameters to construct a multi-physics field coupled simulation model.

[0071] In this embodiment of the invention, the reference design parameters of the pile foundation grounding structure are obtained, and a preset three-dimensional electromagnetic simulation software is called to construct a corresponding multiphysics coupling simulation model based on the reference design parameters.

[0072] It should be noted that the multiphysics coupling simulation model assigns material properties to each component, including electrical conductivity, relative permittivity, and relative magnetic permeability; the soil is set as a lossy medium, and its parameters vary with depth. The computational domain boundary in the multiphysics coupling simulation model is set as a radiation boundary or a perfectly matched layer (PML). The multiphysics coupling simulation model sets a lumped port excitation at the top of the grounding down conductor, injecting a standard 8 / 20μs double exponential waveform lightning current. Potential observation points are set on the surface grid nodes around the pile foundation grounding structure.

[0073] It should be noted that the pile foundation grounding structure includes a concrete pile foundation, a double-helix low-inductance discharge layer, a three-dimensional layered multi-path current dissipation network, a bridging interconnection system, and a U-shaped grounding down conductor. The concrete pile foundation serves as the basic structure of the power pole and provides the installation carrier for subsequent functional layers. Its geometric parameters, such as pile diameter D, height, and underground burial depth, form the basis for the overall structural design. Reinforced concrete is used as the material; although its resistivity is high after curing, efficient lightning current conduction is achieved through the external functional layer. The double-helix low-inductance discharge layer is tightly attached to the outer surface of the concrete pile foundation. It consists of inner and outer helical lines wound in the same direction with a constant pitch, and uses a strip-structured graphene-copper composite material (nominal conductivity...). The strip cross-section is a rectangle of 30mm × 2mm. The difference ΔR between the winding radii of the inner and outer spirals satisfies: ΔR = (0.05~0.15) × D, and the pitch P satisfies: P = (1 / 8~1 / 12) × πD. By reducing the loop inductance through the magnetic field cancellation effect of the reverse current, the coupling coefficient is greater than or equal to 0.85, which can reduce the total inductance by more than 60%, becoming a "low-resistance channel" for the rapid conduction of lightning current. The three-dimensional layered multi-path current dissipation network is distributed at equal intervals along the pile foundation axis (number of layers N≥3), with a ring-shaped horizontal grounding body as the skeleton, and M1 (M1≥4) graphene tile components are vertically fixed. The tiles are centrally symmetrically distributed on the horizontal projection plane. The graphene tiles are prefabricated arc-shaped plates with a curvature radius matching the pile foundation radius, and an arc length Larc = (1 / 6~1 / 8) × πD. A controllable discharge gap with a width δ of 10~30mm is provided between adjacent tiles to maintain high impedance under power frequency to suppress stray current corrosion, and to ionize and form a plasma conductive channel under lightning current impact. The upper and lower adjacent tile assemblies are axially staggered to form a local contact surface occupying 15%~20% of the surface area of ​​a single tile, constructing a three-dimensional continuous conductive path. The bridging interconnection system consists of a copper alloy guide plate with a silver-plated layer (thickness not less than 5μm) and modular clips made of 304 stainless steel. It is used to achieve low-resistance electrical connection between the double-helix low-inductance discharge layer and each layer of the annular horizontal grounding body in the three-dimensional layered multi-path current dissipation network. The contact resistance R at the connection point is... contact With a resistance less than or equal to 10 μΩ, the modular clips can provide a clamping force greater than or equal to 10 MPa, ensuring the stability of current transmission. The lower end of the U-shaped grounding lead is connected to the top of the double-helix low-inductance leakage layer through exothermic welding, and the upper end leads out to the ground to connect to the tower foot or grounding flat steel, serving as a key conduction channel for lightning current to enter the pile foundation grounding structure from the tower, ensuring that transient high currents are efficiently introduced into subsequent leakage and current dissipation components. The pile foundation grounding structure, through the synergy of the low-inductance leakage characteristics of the double-helix layer and the multi-path current dissipation function of the three-dimensional layered network, combined with the high conductivity of graphene composite materials and the intelligent adaptation characteristics of the controllable discharge gap, can significantly reduce the impulse grounding resistance (stable less than or equal to 8.00 Ω), improve the transient potential distribution, and adapt to the lightning protection needs of complex geological environments such as high soil resistivity and strong corrosion.

[0074] The expression for the equivalent total inductance of the double-helix low-inductance bleeder layer at high frequencies is:

[0075]

[0076] in, This is the equivalent total inductance.

[0077] The expression for the coupling coefficient is:

[0078]

[0079] in, The coupling coefficient is... This refers to the mutual inductance between the inner and outer spirals. For the self-inductance of the inner spiral, The self-inductance of the outer spiral.

[0080] The power frequency grounding resistance of a three-dimensional layered multipath current dissipation network can be estimated using a preset correction formula:

[0081]

[0082] in, For power frequency grounding resistance, For soil resistivity, For the equivalent total length of all graphene tile components, The equivalent radius of the grounding electrode. For the single-layer equivalent radius, For structural coefficients, This refers to the number of tile layers.

[0083] Step 202: Construct an initial optimization parameter population using the design parameters to be optimized for the pile foundation grounding structure as individuals.

[0084] In this embodiment of the invention, based on the genetic optimization algorithm, an initial optimization parameter population is constructed using the design parameters to be optimized of the pile foundation grounding structure as individuals according to preset constraints.

[0085] It should be noted that the specific constraints are as follows:

[0086] Larc = (1 / 6 ~ 1 / 8) × πD

[0087] ΔR = (0.05~0.15) × D

[0088] P = (1 / 8 ~ 1 / 12) × πD

[0089] δ is 10~30mm

[0090] Where Larc is the tile arc length, D is the pile diameter, ΔR is the difference in double helix radii, δ is the controllable discharge gap, and P is the double helix pitch.

[0091] It should be noted that the design parameters to be optimized include 13 key parameters such as double helix pitch, double helix radius difference, tile arc length, controllable discharge gap, interlayer contact area ratio, and ring horizontal grounding electrode spacing.

[0092] Step 203: Update the multiphysics coupling simulation model using each of the design parameters to be optimized to obtain multiple target multiphysics coupling simulation models.

[0093] In this embodiment of the invention, each design parameter to be optimized is mapped to a multiphysics coupling simulation model (for example, the value of the double helix pitch directly updates the winding spacing of the helix in the model, and the value of the controllable discharge gap is synchronously adjusted to adjust the gap width between the graphene tile components), thus obtaining multiple target multiphysics coupling simulation models.

[0094] Step 204: Use a preset transient solver to perform coupled solutions on the multiphysics coupling simulation models of each target to obtain multiple surface potentials and multiple injected lightning current amplitudes.

[0095] Surface potential refers to the potential data collected from the observation points of the pre-set surface grid nodes in the target multiphysics coupling simulation model, reflecting the potential magnitude at different locations on the ground surface around the grounding device under lightning current impact.

[0096] The injected lightning current amplitude refers to the peak value of the lightning current applied to the top of the grounding down conductor. It is usually the amplitude of the lightning current of the standard 8 / 20μs double exponential waveform (where "8μs" represents the wavefront time (the time for the current to rise from 0 to the peak value) and "20μs" represents the half-peak time (the time for the current to fall from the peak value to half the peak value)).

[0097] In this embodiment of the invention, a preset transient solver is used to perform coupled solution on each target multiphysics coupling simulation model (i.e., considering the interaction between physical fields (such as the change in material resistivity caused by current heating, which in turn affects the electromagnetic response) and simultaneously solving multiple interrelated physical field control equations (such as the full-wave Maxwell equation of the electromagnetic field and the heat conduction equation of the thermal field) to obtain multiple surface potentials and multiple injected lightning current amplitudes.

[0098] It should be noted that the transient solver refers to the core computational module in simulation software specifically designed to solve transient physical field problems. It can handle physical processes that change with time (such as the electromagnetic-thermal coupling response under transient lightning current impact) and output dynamically changing simulation results through step-by-step iterative calculations.

[0099] Step 205: Perform performance evaluation on each surface potential and each injected lightning current amplitude to obtain multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices.

[0100] Furthermore, step 205 includes the following sub-steps:

[0101] S11. Determine the maximum value of the surface potential corresponding to each injected lightning current amplitude as the maximum surface potential.

[0102] In this embodiment of the invention, the maximum value of the surface potential corresponding to each injected lightning current amplitude is selected as the maximum surface potential.

[0103] S12. Ratio the amplitude of each injected lightning current with the corresponding maximum ground potential to obtain multiple impulse grounding resistances.

[0104] In this embodiment of the invention, each injected lightning current amplitude and the corresponding maximum ground surface potential are input into a preset impulse grounding resistance function to obtain multiple impulse grounding resistances.

[0105] It should be noted that the impulse grounding resistance function is specifically as follows:

[0106]

[0107] in, To reduce the grounding resistance, This is the maximum surface potential. This represents the amplitude of the injected lightning current.

[0108] S13. Input the ground potential corresponding to each injected lightning current amplitude into the preset uniformity function to obtain multiple uniformity indices.

[0109] In this embodiment of the invention, based on a preset uniformity function, the corresponding uniformity index is determined according to the surface potential corresponding to each injected lightning current amplitude.

[0110] It should be noted that the uniformity function is specifically:

[0111]

[0112] in, It is the uniformity index. The average potential, Let be the surface potential of the i-th sampling point. The standard deviation of the potential. The number of valid sampling points is represented by i, where i is the index of the sampling point.

[0113] S14. Based on the preset evaluation weights, perform weighted calculations on each impulse grounding resistance and the corresponding uniformity index to obtain multiple objective function values.

[0114] In this embodiment of the invention, each impulse grounding resistance and its corresponding uniformity index are input into a preset target function to obtain multiple target function values.

[0115] It should be noted that the objective function is as follows:

[0116]

[0117] in, The objective function value, As the first evaluation weight coefficient, This is the second evaluation weighting coefficient.

[0118] Step 206: Iteratively optimize the initial optimization parameter population using each objective function value to obtain the corresponding initial design parameters, and use the impulse grounding resistance and uniformity index corresponding to the initial design parameters as the target simulation parameters.

[0119] Furthermore, step 206 includes the following sub-steps:

[0120] S21. Update the initial optimization parameter population according to each objective function value to obtain a new initial optimization parameter population.

[0121] In this embodiment of the invention, individuals in the initial optimization parameter population are ranked according to the magnitude of each objective function value (the smaller the objective function value, the better the overall structural performance of the corresponding parameter combination). High-ranking individuals are retained first, while low-ranking, poor-performing individuals are removed to reduce redundancy in ineffective parameter combinations. Next, based on the search direction and step size of the Sequential Quadratic Programming (SQP) algorithm, the design parameters to be optimized for the retained high-ranking individuals are fine-tuned and mutated, or new individuals are generated through parameter cross-combinations between high-ranking individuals, thereby obtaining a new initial optimization parameter population.

[0122] S22. Determine whether the number of iterations of the initial optimization parameter population is greater than or equal to the preset iteration threshold.

[0123] The iteration threshold refers to the upper limit of the number of iterations set in advance based on the engineering requirements for optimization accuracy, the computing power limitations of computing equipment, and the complexity of the parameter space to be optimized.

[0124] In this embodiment of the invention, it is determined whether the number of iterations of the initial optimization parameter population has reached a preset iteration threshold.

[0125] S23. When the number of iterations is less than the iteration threshold, the process jumps to the step of updating the multiphysics coupling simulation model with each design parameter to be optimized to obtain multiple target multiphysics coupling simulation models.

[0126] In this embodiment of the invention, when the number of iterations is less than the iteration threshold, the process jumps to step 203.

[0127] S24. When the number of iterations is greater than or equal to the iteration threshold, the design parameter to be optimized corresponding to the minimum value among the objective function values ​​is selected as the initial design parameter.

[0128] In this embodiment of the invention, when the number of iterations reaches the iteration threshold, the design parameter to be optimized corresponding to the minimum value among the objective function values ​​is selected as the initial design parameter.

[0129] Step 207: Verify the initial design parameters based on the target simulation parameters and the multiphysics coupling simulation model to obtain the corresponding target design parameters.

[0130] Furthermore, step 207 includes the following sub-steps:

[0131] S31. Conduct a scaled-down model test using the initial design parameters to obtain the corresponding test parameters.

[0132] The test parameters refer to the uniformity index and impulse grounding resistance obtained through scaled-down model tests.

[0133] In this embodiment of the invention, a scaled-down model is constructed based on a preset scaling ratio and initial design parameters. The scaled-down model is placed in a soil test chamber simulating an actual geological environment. Soil parameters (such as resistivity) are set consistent with those of the multiphysics coupling simulation model. Then, a standard 8 / 20μs double-exponential waveform lightning current is injected into the U-shaped grounding down conductor of the scaled-down model using an impulse current generator. Simultaneously, the surface potential at preset observation points around the pile foundation grounding structure is collected using a potential measuring instrument, and the amplitude of the injected lightning current is recorded using a current sensor. Finally, the corresponding uniformity index and impulse grounding resistance are calculated using the impulse grounding resistance function and the uniformity function.

[0134] S32. Input the target simulation parameters and experimental parameters into the preset calibration function to obtain the corresponding first error value and second error value.

[0135] In this embodiment of the invention, a first error value and a second error value corresponding to the target simulation parameters are determined based on a preset calibration function and experimental parameters.

[0136] It should be noted that the calibration function is as follows:

[0137]

[0138] in, This is the first error value. This is the second error value. The impulse grounding resistance was obtained through a scaled-down model test. The uniformity index is obtained through scaled-down model experiments.

[0139] S33. When the first error value or the second error value is greater than the preset error threshold, the model parameters of the multiphysics coupling simulation model are adjusted, and the process jumps to the step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupling simulation model to obtain the corresponding initial design parameters and target simulation parameters.

[0140] Error threshold refers to the preset critical value at which the judgment error is acceptable. It is determined by the engineering accuracy requirements, the experimental error range, and the accuracy requirements of the simulation model, and is usually set to 10%.

[0141] Model parameters refer to the basic parameters set in a multiphysics coupled simulation model, including soil resistivity, material conductivity, contact resistance, and equivalent parameters of boundary conditions.

[0142] In this embodiment of the invention, when the first error value or the second error value is greater than 10%, the model parameters of the multiphysics coupling simulation model are adjusted, and the process jumps to step 203.

[0143] S34. When both the first error value and the second error value are less than or equal to the error threshold, the initial design parameters are determined as the target design parameters.

[0144] In this embodiment of the invention, when both the first error value and the second error value are 10%, the initial design parameters are determined as the target design parameters.

[0145] It is worth mentioning that, adopting Figure 3 As shown, a double-helix external grounding structure 2 is used to reduce resistance. An external loop grounding network 3 is provided. Ordinary carbon steel is selected as the grounding electrode material, with a conductivity of 5.8 × 10⁶ S / m, a conductor radius of 0.022 m, an axial pitch of 2.7 m, and 6 turns. (See reference...) Figure 4As shown, a pile foundation grounding structure 1 is constructed using the target design parameters. Anchor bolts 4 are installed at the top of pile foundation grounding structure 1. Three-dimensional layered tile components 5 are laid along the main diagonal pile foundation. Four vertical grounding electrodes are installed, with a height of 17.44m and a radius of 0.022m, made of ordinary carbon steel. Five horizontal grounding electrodes are installed, using a ring structure, evenly distributed on the vertical plane, with an outer radius of 0.666m and an inner radius of 0.022m, also made of ordinary carbon steel. Three tile components are installed between adjacent horizontal grounding electrodes, with a chord length of 1 / 6 of the circumference, evenly distributed on the horizontal plane. The tile thickness is 2cm. A 20% local contact surface is formed between the bottom of the upper layer tile and the corresponding lower layer tile. The tiles are made of graphene material with a conductivity of 6×10⁴ S / m. The grounding down conductors for the resistance reduction scheme of pile foundation grounding structure 1 and double-helix external grounding structure 2 are driven in as follows... Figure 5 The lightning impulse current is shown. The potential distribution of the pile foundation grounding structure is observed, and the impulse grounding resistance of the pile foundation grounding structure is calculated to verify the superiority of the invention. (See also...) Figure 6 and Figure 7 As shown, when the soil resistivity rises to 800 Ω·m, the average impulse grounding resistance of the double-helix external grounding structure scheme (13.2 Ω) exceeds the standard limit (10 Ω) over the entire time period. To meet safety requirements, traditional schemes have to compensate by adding an extended radial grounding grid, which not only increases construction costs but also presents implementation difficulties in rocky areas. The pile foundation grounding structure of this application exhibits excellent current dissipation characteristics. Its impulse grounding resistance remains stably maintained at around 7.85 Ω over the entire time range of 0-100 μs, which is 21.5% lower than the national standard limit.

[0146] In this embodiment of the invention, by obtaining the baseline design parameters of the pile foundation grounding structure, a multiphysics field coupled simulation model is constructed using the baseline design parameters. The multiphysics field coupled simulation model is then used to iteratively optimize the design parameters of the pile foundation grounding structure to be optimized, yielding the corresponding initial design parameters and target simulation parameters. The initial design parameters are then verified based on the target simulation parameters and the multiphysics field coupled simulation model to obtain the corresponding target design parameters. This overcomes the technical problem that existing pile foundation grounding structures often rely on empirical formulas or simple static resistance for design, making it difficult to achieve globally optimal design and reducing the reliability of transmission line operation. Compared with traditional pile foundation grounding structure design, this invention uses the baseline design parameters to construct a multiphysics field coupled simulation model, and then uses this model to collaboratively optimize the design parameters of the pile foundation grounding structure to obtain the corresponding target design parameters. This maximizes the comprehensive performance of impulse grounding resistance and transient potential distribution, improving the technical problem of transmission line operation reliability.

[0147] Please see Figure 8 , Figure 8 This is a structural block diagram of a pile foundation grounding structure design system provided in Embodiment 3 of the present invention.

[0148] This invention provides a pile foundation grounding structure design system, comprising:

[0149] Module 301 is used to obtain the reference design parameters of the pile foundation grounding structure and to construct a multi-physics coupling simulation model using the reference design parameters;

[0150] Optimization module 302 is used to iteratively optimize the design parameters of the pile foundation grounding structure using a multi-physics field coupled simulation model to obtain the corresponding initial design parameters and target simulation parameters;

[0151] The verification module 303 is used to verify the initial design parameters based on the target simulation parameters and the multiphysics coupling simulation model, and obtain the corresponding target design parameters.

[0152] Furthermore, the optimization module 302 includes:

[0153] A submodule is constructed to build an initial optimization parameter population based on the design parameters to be optimized for the pile foundation grounding structure.

[0154] The input submodule is used to update the multiphysics coupling simulation model with each design parameter to be optimized, so as to obtain multiple target multiphysics coupling simulation models.

[0155] The solver submodule is used to perform coupled solutions on the multiphysics coupled simulation models of each target using a preset transient solver, so as to obtain multiple surface potentials and multiple injected lightning current amplitudes.

[0156] The evaluation submodule is used to evaluate the performance of each surface potential and each injected lightning current amplitude, and obtain multiple objective function values, multiple impulse grounding resistances and multiple uniformity indices.

[0157] The optimization submodule is used to iteratively optimize the initial optimization parameter population using various objective function values ​​to obtain the corresponding initial design parameters, and uses the impulse grounding resistance and uniformity index corresponding to the initial design parameters as target simulation parameters.

[0158] Furthermore, the evaluation submodule includes:

[0159] The impulse grounding resistance unit is used to determine the maximum value of the ground surface potential corresponding to each injected lightning current amplitude as the maximum ground surface potential.

[0160] The amplitude of each injected lightning current is compared with the corresponding maximum ground surface potential to obtain multiple impulse grounding resistances.

[0161] The uniformity index unit is used to input the surface potential corresponding to each injected lightning current amplitude into a preset uniformity function to obtain multiple uniformity indices.

[0162] The weighting unit is used to perform weighted calculations on each impulse grounding resistance and the corresponding uniformity index based on preset evaluation weights, so as to obtain multiple objective function values.

[0163] Furthermore, sub-modules have been optimized, including:

[0164] The update unit is used to update the initial optimization parameter population based on each objective function value to obtain a new initial optimization parameter population.

[0165] The analysis unit is used to determine whether the number of iterations of the initial optimization parameter population is greater than or equal to the preset iteration threshold;

[0166] When the number of iterations is less than the iteration threshold, the process jumps to the step of updating the multiphysics coupling simulation model with each design parameter to be optimized to obtain multiple target multiphysics coupling simulation models.

[0167] When the number of iterations is greater than or equal to the iteration threshold, the design parameter to be optimized corresponding to the minimum value among the objective function values ​​is selected as the initial design parameter.

[0168] Furthermore, the verification module 303 includes:

[0169] The experimental submodule is used to conduct scaled-down model tests using initial design parameters to obtain the corresponding experimental parameters.

[0170] The calibration submodule is used to input the target simulation parameters and experimental parameters into a preset calibration function to obtain the corresponding first error value and second error value;

[0171] When the first error value or the second error value is greater than the preset error threshold, the model parameters of the multiphysics coupling simulation model are adjusted, and the process jumps to the step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupling simulation model to obtain the corresponding initial design parameters and target simulation parameters.

[0172] When both the first error value and the second error value are less than or equal to the error threshold, the initial design parameters are determined as the target design parameters.

[0173] Furthermore, the design parameters to be optimized include the double helix pitch, the difference in double helix radius, the tile arc length, the controllable discharge gap, the interlayer contact area ratio, and the spacing of the ring-shaped horizontal grounding electrode.

[0174] Please see Figure 9 , Figure 9This is a structural block diagram of an electronic device provided in Embodiment 4 of the present invention.

[0175] An electronic device according to an embodiment of the present invention includes: a memory 401 and a processor 402. The memory 401 stores a computer program. When the computer program is executed by the processor 402, the processor 402 executes the pile foundation grounding structure design method as described in any of the above embodiments.

[0176] Memory 401 may be an electronic memory such as flash memory, EEPROM (Electrically Erasable Programmable Read-Only Memory), EPROM, hard disk, or ROM. Memory 401 has storage space 403 for program code 413 for performing any of the method steps described above. For example, storage space 403 for program code may include individual program codes 413 for implementing the various steps in the methods described above. This program code may be read from or written to one or more computer program products. These computer program products include program code carriers such as hard disks, CDs, memory cards, or floppy disks. The program code may be compressed, for example, in a suitable form. When run by a computing processing device, this code causes the computing processing device to perform the various steps in the methods described above. This program code may be read from or written to one or more computer program products. These computer program products include program code carriers such as hard disks, CDs, memory cards, or floppy disks. The program code may be compressed, for example, in a suitable form. When this code is run by a computing processing device, it causes the device to perform the various steps in the pile foundation grounding structure design method described above.

[0177] Embodiment 5 of the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the pile foundation grounding structure design method as described in any of the above embodiments.

[0178] Embodiment 6 of the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer performs the pile foundation grounding structure design method as described in any of the above embodiments.

[0179] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0180] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0181] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0182] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0183] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0184] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A design method for a pile foundation grounding structure, characterized in that, include: Obtain the reference design parameters of the pile foundation grounding structure, and use the reference design parameters to construct a multiphysics coupling simulation model; The multiphysics coupling simulation model is used to iteratively optimize the design parameters of the pile foundation grounding structure to obtain the corresponding initial design parameters and target simulation parameters. The initial design parameters are verified based on the target simulation parameters and the multiphysics coupling simulation model to obtain the corresponding target design parameters.

2. The pile foundation grounding structure design method according to claim 1, characterized in that, The step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupled simulation model to obtain the corresponding initial design parameters and target simulation parameters includes: An initial optimization parameter population is constructed using the design parameters to be optimized for the pile foundation grounding structure as individuals; The multiphysics coupling simulation model is updated using each of the design parameters to be optimized, resulting in multiple target multiphysics coupling simulation models; A preset transient solver is used to perform coupled solution on each of the target multiphysics field coupled simulation models to obtain multiple surface potentials and multiple injected lightning current amplitudes; The performance of each of the aforementioned surface potentials and each of the aforementioned injected lightning current amplitudes is evaluated to obtain multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices; The initial optimization parameter population is iteratively optimized using each of the objective function values ​​to obtain the corresponding initial design parameters, and the impulse grounding resistance and uniformity index corresponding to the initial design parameters are used as target simulation parameters.

3. The pile foundation grounding structure design method according to claim 2, characterized in that, The step of evaluating the performance of each of the aforementioned surface potentials and each of the injected lightning current amplitudes to obtain multiple objective function values, multiple impulse grounding resistances, and multiple uniformity indices includes: The maximum value of the surface potential corresponding to each of the injected lightning current amplitudes is determined as the maximum surface potential. The amplitude of each injected lightning current is compared with the corresponding maximum ground surface potential to obtain multiple impulse grounding resistances. The surface potential corresponding to each of the injected lightning current amplitudes is input into a preset uniformity function to obtain multiple uniformity indices; Based on preset evaluation weights, weighted calculations are performed on each of the aforementioned impulse grounding resistances and their corresponding uniformity indices to obtain multiple objective function values.

4. The pile foundation grounding structure design method according to claim 2, characterized in that, The step of iteratively optimizing the initial optimization parameter population using each of the objective function values ​​to obtain the corresponding initial design parameters includes: The initial optimization parameter population is updated based on each of the objective function values ​​to obtain a new initial optimization parameter population; Determine whether the number of iterations of the initial optimization parameter population is greater than or equal to a preset iteration threshold; When the number of iterations is less than the iteration threshold, the process jumps to the step of updating the multiphysics coupling simulation model with each of the design parameters to be optimized to obtain multiple target multiphysics coupling simulation models. When the number of iterations is greater than or equal to the iteration threshold, the design parameter to be optimized corresponding to the minimum value among the objective function values ​​is selected as the initial design parameter.

5. The pile foundation grounding structure design method according to claim 1, characterized in that, The step of verifying the initial design parameters based on the target simulation parameters and the multiphysics coupled simulation model to obtain the corresponding target design parameters includes: A scaled-down model test was conducted using the initial design parameters to obtain the corresponding test parameters. The target simulation parameters and the experimental parameters are input into a preset calibration function to obtain the corresponding first error value and second error value; When the first error value or the second error value is greater than the preset error threshold, the model parameters of the multiphysics coupling simulation model are adjusted, and the process jumps to the step of iteratively optimizing the design parameters of the pile foundation grounding structure using the multiphysics coupling simulation model to obtain the corresponding initial design parameters and target simulation parameters. When both the first error value and the second error value are less than or equal to the error threshold, the initial design parameters are determined as the target design parameters.

6. The pile foundation grounding structure design method according to claim 1, characterized in that, The design parameters to be optimized include the double helix pitch, the difference in double helix radius, the tile arc length, the controllable discharge gap, the ratio of interlayer contact area, and the spacing of the ring-shaped horizontal grounding electrode.

7. A pile foundation grounding structure design system, characterized in that, include: A construction module is used to obtain the reference design parameters of the pile foundation grounding structure, and to construct a multiphysics coupling simulation model using the reference design parameters. The optimization module is used to iteratively optimize the design parameters of the pile foundation grounding structure to be optimized using the multiphysics coupling simulation model, so as to obtain the corresponding initial design parameters and target simulation parameters. The verification module is used to verify the initial design parameters based on the target simulation parameters and the multiphysics coupling simulation model, so as to obtain the corresponding target design parameters.

8. An electronic device, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor causes the processor to perform the steps of the pile foundation grounding structure design method as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the pile foundation grounding structure design method as described in any one of claims 1-6.

10. A computer program product, characterized in that, The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, wherein when the program instructions are executed by a computer, the computer performs the pile foundation grounding structure design method as described in any one of claims 1-6.

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