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CN-121997550-A - Lightning transient analysis method and system for high-voltage transmission line

CN121997550ACN 121997550 ACN121997550 ACN 121997550ACN-121997550-A

Abstract

The invention provides a lightning transient analysis method and a system for a high-voltage transmission line, wherein the method comprises the steps of obtaining transmission line parameters, material electromagnetic parameters and atmospheric lightning channel parameters; based on the three-dimensional electromagnetic field partial differential model and a plurality of preset data, performing space dispersion to obtain electric field intensity, current density and magnetic field intensity, obtaining structural material parameters, based on the data and the preset data, obtaining simulation voltage data and simulation current data, obtaining actual measurement data, calculating rise time errors, peak amplitude errors and high-frequency component amplitude-frequency response errors based on the three data, and if the preset convergence condition is met, realizing accurate simulation of the lightning transient process of the high-voltage transmission line. The lightning transient analysis method for the high-voltage transmission line provided by the invention can be used for performing high-precision global simulation on the lightning transient process of the high-voltage transmission line, and providing reliable data support for lightning protection design optimization.

Inventors

  • HAN HAN

Assignees

  • 广东电网有限责任公司广州供电局

Dates

Publication Date
20260508
Application Date
20251224

Claims (10)

  1. 1. The lightning transient analysis method for the high-voltage transmission line is characterized by comprising the following steps of: acquiring transmission line parameters, material electromagnetic parameters and atmospheric lightning stroke channel parameters; Constructing initial three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on transmission line parameters, material electromagnetic parameters and preset grid sizes, and acquiring three-dimensional electromagnetic field partial differential models corresponding to the grid units based on the initial three-dimensional electromagnetic field partial differential models corresponding to the grid units, atmospheric lightning stroke channel parameters, preset waveforms, preset disturbance, preset contact areas and preset time steps; Performing space-time dispersion on the three-dimensional electromagnetic field partial differential model corresponding to any grid unit to obtain electric field intensity corresponding to the grid unit, current density corresponding to the grid unit and magnetic field intensity corresponding to the grid unit; obtaining structural material parameters corresponding to the grid cells; Acquiring simulation voltage data corresponding to the grid unit and simulation current data corresponding to the grid unit based on the electric field intensity, preset reference conductivity, preset reference temperature, the magnetic field intensity, the current density, the structural material parameter and the preset material yield threshold value corresponding to the grid unit; And if the rise time error is smaller than or equal to a preset time threshold value, the peak amplitude error is smaller than or equal to a preset amplitude error threshold value, and the amplitude-frequency response error of the high-frequency component is smaller than or equal to a preset amplitude-frequency response error threshold value, determining that the three-dimensional electromagnetic field partial differential model corresponding to the grid unit meets the preset convergence condition, and realizing the accurate simulation of the lightning transient process of the high-voltage transmission line through the three-dimensional electromagnetic field partial differential model.
  2. 2. The method for lightning transient analysis of a high-voltage transmission line according to claim 1, further comprising: If the rising time error is larger than a preset time threshold, or the peak amplitude error is larger than a preset amplitude error threshold, or the amplitude-frequency response error of the high-frequency component is larger than a preset amplitude-frequency response error threshold, adjusting the electromagnetic parameters or the preset time step of the preset grid size or the material, and recalculating the rising time error, the peak amplitude error and the amplitude-frequency response error of the high-frequency component until the rising time error, the peak amplitude error and the amplitude-frequency response error meet preset convergence conditions, so as to obtain the three-dimensional electromagnetic field partial differential model corresponding to the grid unit.
  3. 3. The method of claim 1, wherein the constructing an initial three-dimensional electromagnetic field partial differential model corresponding to a plurality of grid cells based on the transmission line parameters, the material electromagnetic parameters and the preset grid dimensions, and acquiring a three-dimensional electromagnetic field partial differential model corresponding to a plurality of grid cells based on the initial three-dimensional electromagnetic field partial differential model corresponding to the grid cells, the atmospheric lightning channel parameters, the preset waveform, the preset disturbance, the preset contact area and the preset time step, comprises: Constructing initial three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on transmission line parameters, material electromagnetic parameters and preset grid sizes; Acquiring parameters of an atmospheric lightning stroke channel; Constructing a lightning stroke channel transmission line model based on the atmospheric lightning stroke channel parameters; Generating an initial lightning stroke current based on a preset waveform and a preset disturbance; Constructing a current density source item based on a preset contact area and an initial lightning strike current; And carrying out time synchronization on the initial three-dimensional electromagnetic field partial differential model and the lightning stroke channel transmission line model based on a preset time step, and obtaining three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on the initial three-dimensional electromagnetic field partial differential model after time synchronization and a current density source item.
  4. 4. The method for analyzing lightning transient state of high-voltage transmission line according to claim 3, wherein the constructing initial three-dimensional electromagnetic field partial differential model corresponding to a plurality of grid units based on transmission line parameters, material electromagnetic parameters and preset grid dimensions comprises: Constructing an initial calculation domain; acquiring a three-dimensional calculation domain based on the transmission line parameters and the initial calculation domain; Based on a preset grid size, carrying out grid division on the three-dimensional calculation domain to obtain a plurality of grid units; Mapping the electromagnetic parameters of the material to the corresponding grid cells, and constructing initial three-dimensional electromagnetic field partial differential models corresponding to the grid cells based on a preset Max Wei Shiyu equation set and the electromagnetic parameters of the material.
  5. 5. The method for analyzing lightning transient state of high-voltage transmission line according to claim 1, wherein the performing the time-space dispersion on the three-dimensional electromagnetic field partial differential model corresponding to any grid unit to obtain the electric field intensity corresponding to the grid unit, the current density corresponding to the grid unit and the magnetic field intensity corresponding to the grid unit comprises: performing space dispersion on the three-dimensional electromagnetic field partial differential model corresponding to the grid unit, and constructing a rigidity matrix corresponding to the grid unit, a quality matrix corresponding to the grid unit and an excitation vector corresponding to the grid unit; acquiring a normal differential equation set corresponding to the grid unit based on the rigidity matrix, the quality matrix, the excitation vector and a three-dimensional electromagnetic field partial differential model corresponding to the grid unit; Performing time dispersion on the ordinary differential equation set and solving to obtain a discrete linear model corresponding to the grid unit; acquiring a time coefficient corresponding to the grid unit based on the discrete linear model and a preset solver; and acquiring the electric field intensity corresponding to the grid unit, the current density corresponding to the grid unit and the magnetic field intensity corresponding to the grid unit based on the time coefficient.
  6. 6. The method of claim 4, wherein the obtaining the simulation voltage data and the simulation current data corresponding to the grid cell based on the electric field intensity, the preset reference conductivity, the preset reference temperature, the magnetic field intensity, the current density, the structural material parameter and the preset material yield threshold corresponding to the grid cell comprises: Solving a stress field corresponding to the grid cell based on the electric field intensity, the preset reference conductivity, the preset reference temperature, the magnetic field intensity, the current density and the structural material parameter corresponding to the grid cell; Calculating a fatigue damage factor corresponding to the grid unit based on the stress field and a preset material yield threshold value, and predicting the service life of a device in the corresponding grid unit based on the fatigue damage factor; And acquiring a corresponding life difference value based on the life of the device and the life of a preset standard device, adjusting the preset grid size or material electromagnetic parameters if the life difference value is greater than or equal to a preset life threshold value, and re-predicting the life of the device in the corresponding grid unit until the life difference value is less than the preset life threshold value, and acquiring simulation voltage data corresponding to the grid unit and simulation current data corresponding to the grid unit based on the electric field intensity corresponding to the grid unit, the current density corresponding to the grid unit and the magnetic field intensity corresponding to the grid unit.
  7. 7. The method of claim 6, wherein the solving the stress field corresponding to the grid cell based on the electric field strength corresponding to the grid cell, the preset reference conductivity, the preset reference temperature, the magnetic field strength corresponding to the grid cell, the current density corresponding to the grid cell, and the structural material parameter corresponding to the grid cell comprises: calculating a Joule heat source based on the electric field intensity corresponding to the grid unit, and solving a three-dimensional heat conduction equation based on the Joule heat source to obtain a temperature field corresponding to the grid unit; Calculating the conductivity corresponding to the grid unit based on the temperature field, the preset reference conductivity and the preset reference temperature; solving electromagnetic force distribution corresponding to the grid unit based on the conductivity, the magnetic field intensity corresponding to the grid unit and the current density corresponding to the grid unit; And establishing a three-dimensional elastic mechanical equation based on the electromagnetic force distribution and the structural material parameters corresponding to the grid unit, and solving a stress field corresponding to the grid unit based on the three-dimensional elastic mechanical equation.
  8. 8. The lightning transient analysis system of the high-voltage transmission line is characterized by comprising a parameter acquisition module, a model construction module, a space-time discrete module, a structural material parameter acquisition module, a lightning transient simulation module and a model verification module, and specifically comprises the following components: The parameter acquisition module is used for acquiring transmission line parameters, material electromagnetic parameters and atmospheric lightning stroke channel parameters; the model construction module is used for constructing initial three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on transmission line parameters, material electromagnetic parameters and preset grid sizes, and acquiring three-dimensional electromagnetic field partial differential models corresponding to the grid units based on the initial three-dimensional electromagnetic field partial differential models corresponding to the grid units, atmospheric lightning stroke channel parameters, preset waveforms, preset disturbance, preset contact areas and preset time steps; The space-time discrete module is used for performing space-time discrete on the three-dimensional electromagnetic field partial differential model corresponding to any grid unit to obtain the electric field intensity corresponding to the grid unit, the current density corresponding to the grid unit and the magnetic field intensity corresponding to the grid unit; the structural material parameter acquisition module is used for acquiring structural material parameters corresponding to the grid cells; The lightning transient simulation module is used for acquiring simulation voltage data corresponding to the grid unit and simulation current data corresponding to the grid unit based on the electric field intensity corresponding to the grid unit, preset reference conductivity, preset reference temperature, magnetic field intensity corresponding to the grid unit, current density corresponding to the grid unit, structural material parameters corresponding to the grid unit and a preset material yield threshold; The model verification module is used for obtaining the actual measurement data corresponding to the grid unit, calculating rise time errors, peak amplitude errors and high-frequency component amplitude-frequency response errors based on the actual measurement data corresponding to the grid unit, the simulation voltage data corresponding to the grid unit and the simulation current data corresponding to the grid unit, and determining that the three-dimensional electromagnetic field partial differential model corresponding to the grid unit meets preset convergence conditions if the rise time errors are smaller than or equal to a preset time threshold, the peak amplitude errors are smaller than or equal to a preset amplitude error threshold and the high-frequency component amplitude-frequency response errors are smaller than or equal to a preset amplitude-frequency response error threshold, so that the accurate simulation of the lightning transient process of the high-voltage transmission line through the three-dimensional electromagnetic field partial differential model is realized.
  9. 9. The high voltage transmission line lightning transient analysis system of claim 8, wherein the model verification module is further configured to: If the rising time error is larger than a preset time threshold, or the peak amplitude error is larger than a preset amplitude error threshold, or the amplitude-frequency response error of the high-frequency component is larger than a preset amplitude-frequency response error threshold, adjusting the electromagnetic parameters or the preset time step of the preset grid size or the material, and recalculating the rising time error, the peak amplitude error and the amplitude-frequency response error of the high-frequency component until the rising time error, the peak amplitude error and the amplitude-frequency response error meet preset convergence conditions, so as to obtain the three-dimensional electromagnetic field partial differential model corresponding to the grid unit.
  10. 10. The system of claim 9, wherein the model building module is configured to build an initial three-dimensional electromagnetic field partial differential model corresponding to the plurality of grid cells based on the transmission line parameters, the material electromagnetic parameters, and the predetermined grid dimensions, and obtain a three-dimensional electromagnetic field partial differential model corresponding to the plurality of grid cells based on the initial three-dimensional electromagnetic field partial differential model corresponding to the plurality of grid cells, the atmospheric lightning channel parameters, the predetermined waveform, the predetermined disturbance, the predetermined contact area, and the predetermined time step, and the method comprises: Constructing initial three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on transmission line parameters, material electromagnetic parameters and preset grid sizes; Acquiring parameters of an atmospheric lightning stroke channel; Constructing a lightning stroke channel transmission line model based on the atmospheric lightning stroke channel parameters; Generating an initial lightning stroke current based on a preset waveform and a preset disturbance; Constructing a current density source item based on a preset contact area and an initial lightning strike current; And carrying out time synchronization on the initial three-dimensional electromagnetic field partial differential model and the lightning stroke channel transmission line model based on a preset time step, and obtaining three-dimensional electromagnetic field partial differential models corresponding to a plurality of grid units based on the initial three-dimensional electromagnetic field partial differential model after time synchronization and a current density source item.

Description

Lightning transient analysis method and system for high-voltage transmission line Technical Field The invention relates to the technical field of lightning protection and electromagnetic transient analysis of high-voltage transmission lines, in particular to a lightning transient analysis method and a lightning transient analysis system of a high-voltage transmission line. Background In the operation of a high-voltage transmission line, the lightning strike phenomenon is one of important causes of line insulation breakdown, power failure and even large-range power failure accidents, and the safe and stable operation of a power system is seriously threatened. Therefore, the transient response of the power transmission line under the excitation of lightning stroke is accurately analyzed, and the method has important significance for improving the lightning stroke resistance of a power system, optimizing the design of a lightning protection device and formulating a reliable operation and maintenance strategy. At present, research and engineering application aiming at the lightning transient process of a high-voltage transmission line are mainly focused on three aspects, namely a traditional equivalent circuit model and an electromagnetic transient simulation tool, wherein the equivalent circuit method (Lumped-PARAMETER MODEL) is used for carrying out the equivalent of the transmission line by using segmented inductance, capacitance and resistance elements, a representative tool comprises EMTP (Electromagnetic Transients Program), ATP (ALTERNATIVE TRANSIENTS Program), PSS/E (pulse sequence) and the like, the method has the advantages of simplified model, high calculation efficiency and easy coupling simulation with other parts of a power system, but has the advantages of being incapable of accurately describing the space propagation characteristic of lightning pulse along a wire, and is used for a heterogeneous insulator, The finite difference/finite element method (FDTD/FEM) solves electromagnetic wave equation of time domain or frequency domain through grid discretization continuous space and numerical solution, and is applied to two-dimensional model research of single overhead wire or simple tower structure, and has the advantages of simulating propagation, reflection and scattering of electromagnetic wave, better reflecting distribution parameter characteristics, but the two-dimensional or section model is difficult to fully reflect three-dimensional structure scene, and the calculated amount is square or cubic increased along with grid refinement, so that simulation efficiency is low, and the method is not suitable for large-scale transmission lines, and meanwhile, the method is coupled in multiple physical fields (such as electrothermal effect, electric heating effect, electric heat and the like), dielectric nonlinearity, etc.) lack a uniform and efficient numerical framework. the second is a lightning current excitation model, wherein the International electrotechnical Commission (IEC 62305-1) and IEEE Std C62.41.2 recommend that typical waveforms such as 8/20 mu s and 10/350 mu s are adopted as standard waveform sources of the lightning current model, but the waveform parameters of the model are fixed, the influences of different thunderstorms, diversion locking and tower geometry on the current waveforms are difficult to reflect, and the lightning stroke channel is regarded as a distributed parameter transmission line coupled with an atmospheric electric field and a tower structure by a distributed parameter source model, so that the lightning stroke channel is in a theoretical research stage at present, and a mature engineering implementation method is lacked. The lightning protection device and the grounding system are characterized in that the lightning protection device and the operation maintenance status quo are that the lightning protection wire and the grounding system are used for distributing the lightning protection wire at the top end of the line and guiding lightning current into the grounding network, but the grounding network is designed to be generally configured according to an empirical coefficient, so that the lightning impulse characteristics are difficult to optimize, the hardware and the insulator are used for selecting, the insulator lightning overvoltage tolerance capability depends on experiments and empirical formulas, in a strong lightning area, the insulation configuration of a high-span line is mostly based on an empirical safety margin, the basis of fine design is lacking, on-site monitoring and diagnosis, a part of lines are provided with a current sensor, an overvoltage monitoring device and on-line partial discharge detection, but the monitoring point is limited, the dynamic electromagnetic process of the whole line is difficult to cover, and the post diagnosis depends on broken wire, and as a result, the lightning wire is damaged, and the real-time analysi