Simulation method, system, equipment and medium for rime ice coating growth process of transmission conductor in direct current electric field

Abstract

The invention discloses a simulation method, system, equipment and medium for the rime icing growth process of a transmission conductor under a direct-current electric field, and belongs to the technical field of conductor icing and snowing.The simulation method comprises the steps that conductor structure parameters, meteorological boundary conditions and electric field parameters are set in simulation software, and a simulation model is established; the icing type is controlled to be rime, and the freezing coefficient and the icing surface temperature are obtained by solving the dynamic heat balance equation; a water drop movement path is obtained based on electric field simulation and particle trajectory calculation, and then the collision rate is obtained; the icing amount, the ice density and the thickness of the local infinitesimal are calculated according to the water drop collision parameters, and an ice-shaped boundary is formed through fitting; and judging a simulation termination condition in the process of iteratively updating the ice shape, and outputting the icing shape and weight at the target moment. According to the invention, by simulating the dynamic growth process of rime icing, the physical mechanism of lead icing formation is disclosed, and the defects of long icing test time, low speed and low efficiency can be overcome.

Description

Technical Field

[0001] This invention relates to the field of conductor icing and snow accumulation technology, specifically to a simulation method, system, equipment, and medium for the frost icing growth process of transmission conductors under a DC electric field. Background Technology

[0002] Atmospheric icing takes many forms, and while icing of structures in nature is generally harmless and sometimes even a beautiful natural phenomenon, it poses a serious threat to man-made systems like power grids, particularly transmission line conductors. Icing on transmission line conductors can cause mechanical and electrical accidents. Firstly, the weight of the ice increases the vertical load on the conductor support structure, while the increased wind pressure accompanying the thicker ice layer increases the horizontal load. Uneven icing and asynchronous detachment also impose impact loads on the conductors, leading to conductor galloping. Secondly, ice bridging of insulator strings can cause flashover accidents, and the reduced phase-to-phase distance during conductor galloping can cause phase-to-phase discharge. Conductor icing not only causes substantial economic losses but also disrupts normal social and economic life. Most current conductor icing models are based on unenergized conductors, and the predicted ice volume and shape differ significantly from the actual icing conditions on transmission lines. Therefore, in-depth research on the model of rime ice formation and the development of a simulation method for the growth process of rime ice formation on transmission lines under a DC electric field have practical engineering significance. Summary of the Invention

[0003] In view of the above-mentioned problems, the present invention is proposed.

[0004] Therefore, the technical problem solved by this invention is: how to solve the problem that most current conductor icing models are based on the condition that the conductor is not energized, and the icing amount and shape predicted by the model are quite different from the icing situation on the actual transmission line.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a simulation method for the growth process of rime ice on a power transmission line under a DC electric field, comprising: setting conductor structure parameters, meteorological boundary conditions, and electric field parameters in simulation software to establish a simulation model; controlling the ice type as rime ice, obtaining the freezing coefficient and the surface temperature of the ice by solving the dynamic heat balance equation; obtaining the water droplet motion path based on electric field simulation and particle trajectory calculation, and then calculating the collision rate; calculating the ice amount, ice density, and thickness of local micro-elements based on the water droplet collision parameters, and fitting to form an ice-shaped boundary; determining the simulation termination condition during the iterative update of the ice shape, and outputting the ice shape and weight at the target time.

[0006] As a preferred embodiment of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field as described in this invention, the establishment of the simulation model includes using the conductor structure parameters, meteorological boundary conditions, and electric field parameters as input conditions for the particle trajectory and electric field simulation process.

[0007] As a preferred embodiment of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field as described in this invention, the dynamic heat balance equation includes simplified calculations by setting the freezing coefficient as a constant, so as to obtain the surface temperature of the ice layer for simulation input.

[0008] As a preferred embodiment of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field as described in this invention, the method for determining the simulation termination condition includes judging whether the time has reached the input set value after each calculation and controlling whether to update the ice shape boundary.

[0009] As a preferred embodiment of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field as described in this invention, the step of obtaining the freezing coefficient and the ice surface temperature by solving the dynamic heat balance equation includes: the dynamic heat balance equation has two unknowns, the freezing coefficient and the ice surface temperature; by setting the freezing coefficient in the simulation software and substituting it into the heat balance equation for calculation, the corresponding ice surface temperature value is obtained by inverse solution; the ice surface temperature value is used as the input parameter to control the ice type as rime ice in the simulation, so as to meet the calculation requirements of heat conservation conditions under specific icing conditions.

[0010] This preferred solution sets the freezing coefficient as a constant in the dynamic thermal balance equation and uses simulation software for numerical inverse solution, which can accurately determine the surface temperature of the ice-covered area. This avoids the accumulation of errors caused by parameter uncertainties in traditional methods, thereby effectively ensuring that the simulation input conditions are consistent with the actual thermodynamic state of the rime ice and improving the physical accuracy and control precision of the simulation model.

[0011] As a preferred embodiment of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field as described in this invention, the method for obtaining the water droplet motion path based on electric field simulation and particle trajectory calculation includes: the electric field simulation in the simulation model is performed by constructing a two-dimensional simplified model in the simulation software; the inner conductor with a radius of r is set to be located in a coaxial corona with a radius of R1; the conductor is connected to high voltage; the corona cage is grounded; and the flow field simulation is performed within a rectangular area containing the conductor; the particle trajectory simulation is a transient simulation; the left side is set as the inlet boundary and the right side as the outlet boundary; the conductor and the other walls adopt a no-slip boundary condition; and a fine mesh is used in the area near the conductor, while a coarse mesh is used outside the area to reduce the amount of computation.

[0012] This preferred solution achieves accurate simulation of the force behavior of water droplets under a DC electric field by constructing a simplified two-dimensional model containing a wire and a corona cage in simulation software and combining it with transient simulation of particle trajectories. By using different mesh densities, the area around the wire has higher simulation accuracy, while reducing the overall computational load and improving simulation efficiency and local trajectory fidelity.

[0013] As a preferred embodiment of the simulation method for the frost icing growth process of a power transmission conductor under a DC electric field as described in this invention, the formation of the ice-shaped boundary includes: determining the icing growth at a micro-element position based on the local collision rate calculated from the water droplet trajectory, combining the inlet wind speed, liquid water content, and surface arc length parameters; calculating the ice density at the corresponding position based on the water droplet velocity, water droplet size, and icing surface temperature colliding with the conductor; and calculating the local icing thickness. The water droplet collision position and the corresponding icing thickness are superimposed to generate ice-shaped control points, and a new ice-shaped boundary is formed by fitting the positions of multiple control points.

[0014] This preferred scheme calculates the local collision rate, ice density, and ice thickness, superimposes ice shape control points at different collision locations, and fits them to form boundary curves. This enables dynamic tracking of the ice shape boundary evolution over time, effectively supporting the simulation system's representation of the spatiotemporal distribution of the icing process and improving the visualization accuracy and structural judgment capability of the conductor surface morphology changes.

[0015] Another objective of this invention is to provide a simulation system for the growth process of rime ice on power transmission lines under a DC electric field.

[0016] To address the aforementioned technical problems, this invention provides the following technical solution: a simulation system for the frost accretion growth process of transmission lines under a DC electric field, comprising: a simulation model establishment module, an icing control module, a water droplet trajectory simulation module, an icing calculation module, and a simulation iteration and output module; the simulation model establishment module is used to set conductor structure parameters, meteorological boundary conditions, and electric field parameters in the simulation software to establish a simulation model; the icing control module is used to control the icing type to frost, and obtain the freezing coefficient and icing surface temperature by solving the dynamic heat balance equation; the water droplet trajectory simulation module is used to obtain the water droplet motion path based on electric field simulation and particle trajectory calculation, and then obtain the collision rate; the icing calculation module is used to calculate the icing amount, ice density, and thickness of local micro-elements based on water droplet collision parameters, and fit to form an ice-shaped boundary; the simulation iteration and output module is used to determine the simulation termination condition during the iterative update of the ice shape, and output the icing shape and weight at the target time.

[0017] The present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, characterized in that the processor executes the computer program to implement the steps of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field.

[0018] The present invention provides a computer-readable storage medium having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements the steps of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field.

[0019] The beneficial effects of this invention are as follows: This invention reveals the physical mechanism of conductor icing formation by simulating the dynamic growth process of rime ice. It can provide theoretical support and engineering guidance for the formulation of anti-icing and de-icing strategies for power transmission systems and the safe operation and maintenance of power grids. Specifically, it can be applied to key technical fields such as ice thickness prediction, de-icing parameter optimization, and anti-icing protection of power equipment. This invention can overcome the shortcomings of long icing test time, slow speed, and low efficiency. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0021] Figure 1 The above is a flowchart of a simulation method for the growth process of rime ice on a power transmission line under a DC electric field, provided as an embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of a rectangular simulation area for a simulation method of the frost and ice growth process of a power transmission line under a DC electric field, provided in one embodiment of the present invention.

[0023] Figure 3 This is a schematic diagram of the simulation mesh generation for a simulation method of the frost and ice growth process of a power transmission line under a DC electric field, provided as an embodiment of the present invention.

[0024] Figure 4 The image shows a comparison of ice-shaped boundaries on the conductor surface with a field strength of 10 kV / cm, provided as an embodiment of the present invention, to simulate the growth process of rime ice on a power transmission conductor under a DC electric field.

[0025] Figure 5 The image shows a comparison of ice-shaped boundaries on the conductor surface with an electric field strength of 15 kV / cm, provided as an embodiment of the present invention, to simulate the growth process of rime ice on a power transmission conductor under a DC electric field.

[0026] Figure 6 This is a schematic diagram of a simulation system for the growth process of rime ice on a power transmission line under a DC electric field, provided as an embodiment of the present invention. Detailed Implementation

[0027] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0028] Example 1, referring to Figure 1 This is one embodiment of the present invention, which provides a simulation method for the growth process of rime ice on transmission lines under a DC electric field, including:

[0029] S1. Set the conductor structure parameters, meteorological boundary conditions, and electric field parameters in the simulation software to establish a simulation model.

[0030] S2. Control the icing type to be rime, and obtain the freezing coefficient and icing surface temperature by solving the dynamic heat balance equation.

[0031] S3. Obtain the water droplet motion path based on electric field simulation and particle trajectory calculation, and then calculate the collision rate.

[0032] S4. Calculate the ice coverage, ice density, and thickness of the local micro-element based on the water droplet collision parameters, and fit to form an ice-shaped boundary.

[0033] S5. Determine the simulation termination condition during the iterative update of the ice shape, and output the ice shape and weight at the target time.

[0034] When transmission lines operate in cold and humid environments, rime ice is a typical type of icing. Because the DC electric field significantly affects the motion of water droplets, traditional prediction models that only consider meteorological factors struggle to accurately recreate the ice formation process. Furthermore, the formation of rime ice involves complex electrothermal-fluid coupling and particle dynamics issues, making complete measurement difficult in actual transmission systems. Therefore, this invention constructs a parameter-adjustable simulation model, combining electric field simulation, particle trajectory simulation, and ice formation evolution mechanisms, to provide visualized predictions of the icing morphology and growth process on the conductor surface, offering theoretical support and decision-making basis for the operational safety of high-voltage transmission lines.

[0035] Example 2, refer to Figure 2 and Figure 3 As an embodiment of the present invention, based on the previous embodiment, a simulation method for the growth process of rime ice on transmission lines under a DC electric field is provided, comprising:

[0036] In the embodiments of this application, in step S1, the conductor structure parameters, meteorological boundary conditions and electric field parameters are set in the simulation software to establish a simulation model.

[0037] The conductor structure parameters, meteorological boundary conditions, and electric field parameters are used as input conditions in the particle trajectory and electric field simulation process.

[0038] Specifically, the initial conditions for the simulation are set in the simulation software, such as temperature, liquid water content, wind speed, wire diameter, corona cage radius, water droplet diameter, surface electric field strength, number of released particles, and simulation step size.

[0039] In one alternative implementation, a coaxial corona structure is established by adjusting the spatial scale relationship between the conductor diameter and the corona cage radius in the conductor structure parameters, so as to form the high-voltage conductor and grounding boundary conditions in the simulation, and assist in setting the electric field simulation boundary in the simulation model.

[0040] In another alternative implementation, the source of water droplets in the simulation is controlled by using liquid water content, wind speed, and droplet diameter as input boundary conditions in combination at the particle release inlet; and a simulation step size is set to limit the time update frequency of particle trajectory evolution and ice thickness calculation.

[0041] This invention establishes a two-dimensional rectangular simulation region by uniformly setting the above parameters in the simulation software, and then runs it in conjunction with steady-state and transient solvers to form a basic simulation domain for subsequent analysis of the entire process of particle motion, water droplet collision and icing modeling.

[0042] In this embodiment of the application, the ice type is controlled to be rime in step S2, and the freezing coefficient and the surface temperature of the ice are obtained by solving the dynamic heat balance equation.

[0043] The icing type is controlled as rime ice. The freezing coefficient and the icing surface temperature are obtained by solving the dynamic heat balance equation. The dynamic heat balance equation has two unknowns: the freezing coefficient and the icing surface temperature. By setting the freezing coefficient in the simulation software and substituting it into the heat balance equation for calculation, the corresponding icing surface temperature value is obtained through inverse solving. This icing surface temperature value serves as the input parameter for controlling the icing type as rime ice in the simulation, thus meeting the calculation requirements of heat conservation conditions under specific icing conditions.

[0044] The overall freezing coefficient was calculated by combining parameters such as temperature, wind speed, and conductor radius, and the icing type was controlled to be rime.

[0045] The following principles apply to rime ice formation: The overall freezing coefficient needs to be calculated, which is obtained from the heat balance equation of the ice-covered surface.

[0046] q c+q e +q l +q s =q f +q v +q k +q a

[0047] The left side of the heat balance equation represents the heat absorbed from the ice-covered surface, including the heat lost through air convection, q. c The heat q lost through water evaporation or ice sublimation e The colliding particles absorb heat q as the ambient temperature rises to the freezing point of the water droplet. l and radiative heat loss q s The corresponding calculation formula is as follows:

[0048]

[0049] Where T is the ambient temperature, T s R is the surface temperature of the iced surface, h is the convective heat transfer coefficient of the iced surface, χ is the evaporation or sublimation coefficient, e(T) is the saturated vapor pressure (kPa) of the water or ice surface at temperature T, V is the air velocity, ω is the liquid water content, a1 is the collision coefficient, a2 is the capture coefficient, and c is the saturated vapor pressure (kPa) of the iced surface. w For the specific heat of water, T F Let ε be the freezing temperature of water, ε be the emissivity of the ice-covered outer surface, and σ be the emissivity of the ice-covered outer surface. R This is the Stefan-Boltzman constant.

[0050] The right side of the heat balance equation represents the heat released to the ice-covered surface, including the latent heat q released by the frozen particles. f Heat release q from airflow friction with the wire v The kinetic energy q of the water droplet colliding with the wire k The energy q released when water freezes and cools from its freezing point to the surface temperature of the ice layer. a The corresponding calculation formula is as follows:

[0051]

[0052] Where a3 is the freezing coefficient, L f For the latent heat of melting ice, r c c is the coefficient of thermal recovery. a v is the specific heat of air. d Let c be the collision velocity of the water droplets. i It is the specific heat of ice.

[0053] Based on the above formula, a program was written in the simulation software. In the formula, there exists a freezing coefficient a3 and an ice-covered surface temperature T. sGiven two unknowns, first set the unfreezing coefficient a3 to 1 to ensure the icing type is rime, then solve for T. s , to be used in subsequent simulations.

[0054] In this embodiment of the application, the water droplet motion path is obtained in step S3 based on electric field simulation and particle trajectory calculation, and then the collision rate is obtained.

[0055] In the simulation model, the electric field simulation is carried out by constructing a two-dimensional simplified model in the simulation software. The inner conductor with a radius of r is set in a coaxial corona with a radius of R1. The conductor is connected to high voltage, the corona cage is grounded, and the flow field simulation is performed in a rectangular area containing the conductor. The particle trajectory simulation is a transient simulation. The left side is set as the inlet boundary and the right side as the outlet boundary. The conductor and the other walls adopt no-slip boundary conditions. The region near the conductor is fine-meshed, and the outside of the region is coarsened to reduce the amount of computation.

[0056] Specifically, boundary conditions of the physical field are set, such as inlet wind speed, outlet pressure, electric potential, grounding and frozen wall conditions, and steady-state electric field simulation and transient particle trajectory simulation are performed to obtain the water droplet trajectory; the collision rate parameter is calculated based on the simulated water droplet trajectory.

[0057] The following principles are adopted for steady-state electric field simulation:

[0058] First, an inner conductor with radius r is placed in a coaxial corona cage with radius R1. The conductor is connected to a high voltage, the corona cage is grounded, and the wind is a horizontal wind from left to right. The magnitude of the surface electric field strength of the smooth cylindrical conductor is calculated by the following formula:

[0059]

[0060] Where R1 is the radius of the corona cage, r is the radius of the conductor, and U0 is the magnitude of the high voltage connected to the conductor.

[0061] Secondly, to reduce computational load, the flow field is calculated only within a rectangular domain containing the conductor. The height and width of the rectangular domain are chosen to be 8D and 15D, respectively, where D is the conductor diameter. The length of the conductor on the windward side is set to 10D, assuming that the influence of the electric field on the droplet's motion is negligible when the droplet is outside this region. For a fixed cylindrical conductor, icing often only occurs on the windward side, so the length on the leeward side can be slightly shorter; the leeward side length is set to 5D, as shown in the attached figure. Figure 2 As shown.

[0062] Finally, set appropriate boundary conditions, with the left side of the rectangle serving as the inlet boundary, and specify the normal inflow velocity U of the air. in=5 m / s; the right side is the outlet boundary, specified with pressure boundary conditions. The conductor and other walls use no-slip boundary conditions. An ultra-fine mesh is used inside the rectangular region, with further refinement of the boundary layer on the walls to ensure computational accuracy near the conductor; a coarser mesh is used outside the rectangular region to reduce computational load. The mesh based on this division is attached. Figure 3 As shown.

[0063] The following principles are adopted for transient particle trajectory simulation:

[0064] For a water droplet near a conductor under a DC electric field, assuming the mass of the droplet is constant, the vector equation describing the droplet's motion is:

[0065]

[0066] Where, m d It is the mass of the water droplet, F d For air resistance, F gb For buoyancy and gravity, F dep For dielectrophoresis force, F e V is the electric field force, and V1 is the velocity of the water droplet.

[0067] The formula for calculating resistance is as follows:

[0068]

[0069] Among them, F d For resistance, A = πa² is the cross-sectional area of ​​the water droplet, V is the air velocity, u is the velocity of the water droplet, and C is the air velocity. D The drag coefficient is a dimensionless coefficient that depends only on the relative Reynolds number Re of the particle. r Related, ρ is the fluid density:

[0070]

[0071] Where 'a' is the correlation coefficient, 'υ' is the kinematic viscosity, and the formula for the drag coefficient uses the standard drag correlation, segmented according to the relative Reynolds number:

[0072]

[0073] The formulas for calculating buoyancy and gravity are as follows:

[0074] F gb =(ρ d -ρ)V d g

[0075] Where, ρ d Let V be the density of the water droplet. dLet g be the volume of the water droplet, g be the acceleration due to gravity, and ρ be the fluid density.

[0076] The formula for calculating dielectric force is as follows:

[0077]

[0078] Where ε0 is the vacuum permittivity, ε1 is the permittivity of the fluid, ε2 is the permittivity of the water droplet, a is the radius of the water droplet, and E is the electric field strength. The gradient is the square of the electric field strength.

[0079] The formula for calculating electric force is as follows:

[0080] F e =qE

[0081]

[0082] Where q is the water droplet charge, which is time-dependent, and E is the electric field strength. τ is the time constant related to corona discharge, τ = 4ε0 / N0eμi, where N0 is the ion number density and μi is the ion mobility. εr is the dielectric constant of the water droplet, and ε0 is the dielectric constant of the air fluid.

[0083] Furthermore, the collision rate parameter is calculated using the following principles:

[0084]

[0085] Where, d y d is the difference in the ordinates of the trajectories of adjacent particles at the starting position. l This corresponds to the arc length of the particle trajectory along the ice-covered surface.

[0086] In the embodiments of this application, in step S4, the amount of ice covering, ice density and thickness of local micro-elements are calculated based on the water droplet collision parameters, and an ice-shaped boundary is formed by fitting.

[0087] Based on the local collision rate calculated from the droplet trajectory, combined with the inlet wind speed, liquid water content, and surface arc length parameters, the icing growth at the micro-element position is determined. Combining the droplet velocity, droplet size, and icing surface temperature that collide with the conductor, the ice density at the corresponding position is calculated, and the local icing thickness is also calculated. The droplet collision position and the corresponding icing thickness are superimposed to generate ice shape control points. By fitting the positions of multiple control points, a new ice shape boundary is formed.

[0088] Specifically, the amount of ice on the surface micro-element is obtained from the local collision rate, and the ice density on the surface micro-element is calculated from the velocity of the water droplets colliding with the ice-covered surface. Combining the two, the thickness of the ice growth on the surface micro-element can be obtained. By selecting control points and fitting the curve, a new ice-covered shape can be obtained.

[0089] The amount of icing is calculated from the local collision rate:

[0090] m i =β i V ∞ ωl i Δt

[0091] Where, m i Let V be the icing amount on the i-th infinitesimal element, and let V be the local collision coefficient on the i-th infinitesimal element. ∞ ω is the inlet wind speed, l is the liquid water content, and l is the inlet wind speed. i Let be the arc length of the i-th infinitesimal element, and Δt be the time step of the iteration.

[0092] Ice density is calculated using the following formula:

[0093]

[0094] Among them, v d Let r be the velocity of the water droplet colliding with the wire. d Let T be the radius of the water droplet. s ρ is the surface temperature of the ice-covered surface. i Let be the local ice density on the i-th infinitesimal element, in kg / m³. The ice thickness is calculated using the following formula:

[0095]

[0096] Among them, l i It is the length of the locally icing micro-element.

[0097] The ice shape control point is obtained by adding the ice growth thickness to the collision location of the water droplet. The ice shape boundary is obtained by fitting the control points obtained from different collision locations.

[0098] In this embodiment of the application, in step S5, the simulation termination condition is determined during the iterative update of the ice shape, and the ice shape and weight at the target time are output.

[0099] After each calculation, it is determined whether the time has reached the input set value, and whether the ice shape boundary is updated.

[0100] Specifically, after each iteration, it is determined whether the input icing time has been reached; if the time has not been reached, the updated ice shape, updated mesh and boundary conditions are used, and the previous steps are repeated; if the time has been reached, the corresponding icing amount and icing shape data are output.

[0101] In one alternative implementation, the simulation termination condition is set by the user through a target time input. Combined with the external power grid operation requirements or experimental time window requirements, a fixed simulation step size and total number of iterations are set, and the system determines whether the termination condition is met based on the accumulation of time.

[0102] In another optional implementation, the simulation termination condition is combined with the ice-shaped boundary data generated in the simulation for auxiliary judgment. If the boundary change amplitude is lower than a certain set threshold in multiple consecutive iterations (such as no longer increasing significantly), the system determines that the simulation has reached a stable state, terminates the simulation process in advance, and outputs the ice-covered shape data at the current moment.

[0103] This invention optimizes computational efficiency while ensuring result accuracy by setting simulation time and judging boundary states in real time, and can flexibly adapt to simulation termination strategies under different operating conditions.

[0104] Example 3, referring to Figure 4 and Figure 5 This invention provides a simulation method for the growth process of rime ice on power transmission lines under a DC electric field. To verify the beneficial effects of this invention, scientific demonstration is carried out through experiments.

[0105] A charged icing experiment was conducted in an artificial climate chamber. The relevant parameters are as follows: wind speed (1.5 m / s), water droplet diameter (62.2 μm), wire diameter (3.0 cm), ambient temperature (-8.0℃), and liquid water content (1.2 g / m³). The simulation method of this invention was then used to perform a simulation, resulting in a comparison diagram of the ice-shaped boundary, as shown below. Figure 4 and Figure 5 As shown.

[0106] The experimental data and simulation results show that the simulation model can predict the amount and density of ice cover very well, with a relative error of less than 5%. The simulation method is applicable and fast, and can quickly obtain the ice cover situation, making up for the shortcomings of the experiment which requires a lot of manpower and material resources.

[0107] Example 4, refer to Figure 6 This embodiment of the present invention provides a simulation system for the growth process of rime ice on transmission lines under a DC electric field, including a simulation model establishment module, an icing control module, a water droplet trajectory simulation module, an icing calculation module, and a simulation iteration and output module.

[0108] The simulation model building module is used to set conductor structure parameters, meteorological boundary conditions, and electric field parameters in the simulation software to build a simulation model.

[0109] The icing control module is used to control the icing type to be rime, and obtains the freezing coefficient and the surface temperature of the icing by solving the dynamic heat balance equation.

[0110] The water droplet trajectory simulation module is used to obtain the water droplet's motion path based on electric field simulation and particle trajectory calculation, and then to obtain the collision rate.

[0111] The icing calculation module is used to calculate the amount of ice, ice density and thickness of local micro-elements based on the water droplet collision parameters, and to fit and form an ice-shaped boundary.

[0112] The simulation iteration and output module is used to determine the simulation termination condition during the iterative update of the ice shape and output the ice shape and weight at the target time.

[0113] This embodiment also provides an electronic device applicable to a simulation method for the growth process of frost accretion on transmission lines under a DC electric field, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to realize the simulation method for the growth process of frost accretion on transmission lines under a DC electric field as proposed in the above embodiment.

[0114] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a simulation method for the growth process of rime ice on a power transmission line under a DC electric field, as proposed in the above embodiment.

[0115] The storage medium proposed in this embodiment and the simulation method for realizing the growth process of rime ice on a power transmission line under a DC electric field proposed in the above embodiment belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0116] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0117] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A simulation method for the growth process of rime ice on transmission lines under a DC electric field, characterized in that: include, In the simulation software, set the conductor structure parameters, meteorological boundary conditions, and electric field parameters to establish a simulation model; The ice type was controlled as rime, and the freezing coefficient and ice surface temperature were obtained by solving the dynamic heat balance equation. The water droplet motion path is obtained based on electric field simulation and particle trajectory calculation, and then the collision rate is calculated. The amount of ice, ice density, and thickness of local micro-elements are calculated based on the water droplet collision parameters, and an ice-shaped boundary is formed by fitting the data. During the iterative update of the ice shape, the simulation termination condition is determined, and the ice shape and weight at the target time are output.

2. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 1, characterized in that: The establishment of the simulation model includes using conductor structure parameters, meteorological boundary conditions, and electric field parameters as input conditions for the particle trajectory and electric field simulation process.

3. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 2, characterized in that: The dynamic thermal balance equation includes simplified calculations by setting the freezing coefficient as a constant, and the inverse solution is used to obtain the ice-covered surface temperature for simulation input.

4. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 3, characterized in that: The simulation termination condition includes determining whether the time has reached the input set value after each calculation and controlling whether to update the ice-shaped boundary.

5. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 4, characterized in that: The freezing coefficient and the ice-covered surface temperature are obtained by solving the dynamic heat balance equation. include, The dynamic heat balance equation has two unknowns: the freezing coefficient and the ice-covered surface temperature. By setting the freezing coefficient in the simulation software and substituting it into the heat balance equation for calculation, the corresponding ice-covered surface temperature value is obtained by inverse solution. The ice-covered surface temperature value is used as the input parameter to control the ice type as rime in the simulation, so as to meet the calculation requirements of heat conservation conditions under specific icing conditions.

6. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 4, characterized in that: The water droplet motion path is obtained based on electric field simulation and particle trajectory calculation. include, The electric field simulation in the simulation model is carried out by constructing a two-dimensional simplified model in the simulation software. The inner conductor with a radius of r is set in a coaxial corona with a radius of R1. The conductor is connected to high voltage, the corona cage is grounded, and the flow field simulation is carried out in a rectangular area containing the conductor. The particle trajectory simulation is a transient simulation. The left side is set as the inlet boundary and the right side as the outlet boundary. The wire and the other walls adopt no-slip boundary conditions. The region near the wire is given a fine mesh, and the region outside the wire is given a coarse mesh to reduce the amount of computation.

7. The simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in claim 4, characterized in that: The formation of the ice-shaped boundary includes the local collision rate calculated based on the water droplet trajectory, combined with the inlet wind speed, liquid water content and surface arc length parameters, to determine the ice growth at the micro-element position, combined with the water droplet velocity, water droplet size and ice surface temperature that collide with the conductor, to calculate the ice density at the corresponding position, and to calculate the local ice thickness. The collision points of water droplets are superimposed with the corresponding ice thickness to generate ice shape control points. By fitting the positions of multiple control points, a new ice shape boundary is formed.

8. A simulation system for the growth process of rime ice on transmission lines under a DC electric field, employing the simulation method for the growth process of rime ice on transmission lines under a DC electric field as described in any one of claims 1 to 7, characterized in that, include: The simulation model building module, icing control module, water droplet trajectory simulation module, icing calculation module, and simulation iteration and output module are included. The simulation model building module is used to set conductor structure parameters, meteorological boundary conditions, and electric field parameters in the simulation software to build a simulation model; The icing control module is used to control the icing type to be rime, and obtains the freezing coefficient and the icing surface temperature by solving the dynamic heat balance equation. The water droplet trajectory simulation module is used to obtain the water droplet motion path based on electric field simulation and particle trajectory calculation, and then to obtain the collision rate; The icing calculation module is used to calculate the amount of ice, ice density and thickness of local micro-elements based on the water droplet collision parameters, and to fit and form an ice-shaped boundary. The simulation iteration and output module is used to determine the simulation termination condition during the iterative update of the ice shape and output the ice shape and weight at the target time.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field, as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the simulation method for the growth process of rime ice on a power transmission line under a DC electric field, as described in any one of claims 1 to 7.

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