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CN-121997301-A - Construction method and system of ice coating analysis database of micro-topography micro-meteorological transmission line

CN121997301ACN 121997301 ACN121997301 ACN 121997301ACN-121997301-A

Abstract

The invention provides a construction method and a construction system of an icing analysis database of a micro-terrain micro-meteorological transmission line, and relates to the technical fields of disaster prevention and reduction of electric power systems and electric network meteorological application. The method comprises the steps of carrying out space-time alignment on original DEM data and original analysis meteorological data of a complex mountain area to obtain a basic data set, carrying out dynamic downscaling simulation by taking re-analysis meteorological data in the basic data set as a large-scale background field and boundary conditions and taking DEM data in the basic data set as a terrain forcing field, carrying out vertical gradient correction aiming at the actual height of a power transmission line based on boundary layer theory, extracting micro-topography factors of a corridor area of the power transmission line, carrying out local micro-scale topography effect correction by utilizing the micro-topography factors, and constructing an icing analysis database of the power transmission line based on the micro-topography factors and the high space-time resolution analysis meteorological data. The method solves the problem that the existing icing prediction of the complex mountain area is low in accuracy and precision.

Inventors

  • YE YU
  • YU HUA
  • LU ZHUMAO
  • YUAN HUI
  • MENG XIAOKAI
  • XU XUNJIAN
  • LU ZICHAO
  • TANG WENBO
  • ZHAO BINBIN
  • TAN HAOCHEN
  • LIU YI
  • KONG XIAOANG
  • LI JINSONG

Assignees

  • 国网电力工程研究院有限公司
  • 国网山西省电力有限公司电力科学研究院

Dates

Publication Date
20260508
Application Date
20251222

Claims (20)

  1. 1. The construction method of the icing analysis database of the micro-topography micro-meteorological transmission line is characterized by comprising the following steps of: Carrying out space-time alignment on the acquired original Digital Elevation Model (DEM) data of the complex mountain region and the original analysis meteorological data to obtain a basic data set; Taking the analysis meteorological data in the basic data set as a large-scale background field and boundary conditions, and taking the DEM data in the basic data set as a terrain forcing field, performing dynamic downscaling simulation to obtain a mesoscale meteorological field of a target iceberg area; Performing vertical gradient correction aiming at the actual height of the power transmission line on the mesoscale gas image field based on boundary layer theory to obtain mesoscale distribution fields of all meteorological elements of the wire height layer; Utilizing the micro-topography factors to correct local micro-scale topography effect of each meteorological element mesoscale distribution field of the wire height layer, and generating high space-time resolution analysis meteorological data of a target icing mountain area; and constructing an ice coating analysis database of the power transmission line based on the micro-topography factors and the high space-time resolution analysis meteorological data of the target ice coating mountain area.
  2. 2. The method of claim 1, wherein the micro-topography factors include at least grade, slope, topography relief, topography shielding, and wind corridor index; The terrain shielding degree is used for representing windward/leeward characteristics of each spatial position of the target icing mountain area in different directions; the wind porch index is used for representing the diversion and contraction effect of the terrain at each spatial position of the target icing mountain area on the wind field.
  3. 3. The method of claim 2, wherein the process of extracting the terrain shielding degree comprises: For a space position in a power transmission line corridor area of a target icing mountain area in the basic data set, performing terrain shielding scanning along a plurality of azimuth angles of the space position, and calculating the terrain shielding degree of the space position; The extraction process of the wind corridor index comprises the following steps: For a spatial location within a transmission line corridor area of a target iceberg area in the base dataset, a wind corridor index for the spatial location is calculated based on a dominant wind direction and topographical profile features of the spatial location extracted from the base dataset.
  4. 4. A method according to claim 3, wherein calculating the degree of terrain shielding for the spatial location by performing a terrain shielding scan along a plurality of azimuth angles of the spatial location comprises: Taking the space position as the center, scanning the terrain upstream along a plurality of azimuth angles of the space position, and determining the height of a scanning point for shielding incoming wind and the horizontal distance between the scanning point and the space position; Determining a maximum shielding angle of the scanning point in the azimuth direction based on the height of the scanning point and the horizontal distance between the scanning point and the space position; and carrying out normalization processing on the maximum shielding angles in the azimuth directions to obtain the terrain shielding degree of the space position.
  5. 5. A method according to claim 3, wherein calculating wind porch-way indices of the spatial location based on the dominant wind direction and topographical profile features of the spatial location extracted from the base dataset comprises: determining the dominant wind direction of the corridor area of the power transmission line based on statistical analysis of historical periods of DEM data and analysis meteorological data in the basic data set; extracting a topography profile along the transmission line along the dominant wind direction of the transmission line corridor area to obtain an elevation difference characteristic, a gradient characteristic along the dominant wind direction and an effective channel characteristic along the dominant wind direction of the spatial position; obtaining a wind corridor index of the spatial position based on weighted fusion of the elevation feature, the slope feature along the wind direction and the effective channel feature along the wind direction of the spatial position; wherein the effective channel along the dominant wind direction is characterized by an aspect ratio of the effective channel having valley characteristics in the dominant wind direction.
  6. 6. The method of claim 1, wherein the performing the spatiotemporal alignment of the acquired raw DEM data and raw analytic meteorological data for the complex mountain region to obtain a base data set comprises: Carrying out projection mapping and resampling aiming at a target plane coordinate system on longitude and latitude grids of original DEM data of a complex mountain region to obtain a preprocessed elevation field; performing projection mapping and spatial interpolation aiming at a target plane coordinate system on near-earth meteorological elements in original re-analyzed meteorological data of a complex mountain region to obtain a fine grid meteorological field; Converting the time step of the fine grid meteorological field into a target time step by utilizing linear time interpolation to obtain a preprocessed meteorological field; the base dataset is derived based on the post-pretreatment altitude Cheng Chang and the post-pretreatment meteorological field.
  7. 7. The method of claim 2, wherein performing dynamic downscaling simulation with the re-analyzed meteorological data in the base data set as a large scale background field and boundary conditions and the DEM data in the base data set as a terrain forcing field to obtain a mesoscale meteorological field for the target iceberg area, comprising: configuring multiple nested grids for a preset mesoscale numerical weather forecast mode, mapping DEM data in the basic data set to each layer of grids of the mesoscale numerical weather forecast mode through spatial interpolation, and generating a mode terrain altitude field; performing vertical interpolation and variable conversion on the analysis meteorological data in the basic data set to generate an initial field and boundary conditions of three-dimensional space-time dependence required by the mesoscale numerical weather forecast mode; And (3) using the mode terrain height field as an underlying surface to force, using the three-dimensional space-time dependent initial field and boundary conditions as driving and constraint, operating the mesoscale numerical weather forecast mode, and screening a mesoscale weather image field of a target icing mountain area on an inner grid of the mesoscale numerical weather forecast mode.
  8. 8. The method of claim 7, wherein the mesoscale meteorological field comprises a mesoscale air temperature field, a mesoscale wind speed field, a mesoscale wind direction field, a mesoscale humidity field and a mesoscale precipitation variable field, wherein the perpendicular gradient correction for the actual height of the power transmission line is performed on the mesoscale meteorological field based on boundary layer theory to obtain a mesoscale distribution field of each meteorological element of the wire height layer, and the method comprises the following steps: Calculating the temperature vertical gradient of each grid unit in the corridor area of the mesoscale air temperature field power transmission line based on the air temperature and the height of two adjacent mode layers on the basis of the height of a wire by utilizing a boundary layer theory; for each grid unit in the corridor area of the mesoscale wind speed field power transmission line, based on boundary layer theory, utilizing a wind speed profile power law index to extrapolate the wind speed of any near stratum height to the wire height, and obtaining the corrected wind speed at the wire height of the grid unit; Taking the near stratum wind direction of the mesoscale wind direction field as the wind direction of the conducting wire height layer; For the mesoscale humidity field and the mesoscale precipitation variable field, respectively diagnosing or extrapolating in the vertical direction aiming at the height of the lead to obtain relative humidity and precipitation related variables of the height layer of the lead; generating a mesoscale distribution field of each meteorological element of the wire height layer based on the corrected air temperature and corrected air speed of each grid unit in the corridor area of the power transmission line and the relevant variables of wind direction, relative humidity and precipitation of the wire height layer; Wherein the wind speed profile power law index is determined based on the underlying roughness of the mesoscale wind speed field.
  9. 9. The method of claim 8, wherein locally microscale terrain effect correction is performed on the scale distribution field in each meteorological element of the wire height layer using the microscale terrain factors to generate high-space-time resolution re-analyzed meteorological data for a target iceberg area, comprising: Performing microscale correction on the air temperature distribution field of the wire height layer based on the topographic relief, the topographic shielding degree and the wind corridor index in the microscale factors to obtain a microscale corrected air temperature distribution field of the wire height layer; Based on the wind corridor index, the terrain shielding degree and the gradient in the micro-topography factors, carrying out acceleration effect correction on the wind speed field of the wire height layer to obtain a wind speed distribution field of the wire height layer after micro-scale correction; based on the microscale corrected air temperature distribution field of the wire height layer and the microscale corrected wind speed distribution field of the wire height layer, correcting the distribution fields of other meteorological elements of the wire height layer by utilizing the association relation between different meteorological elements; Forming high space-time resolution analysis meteorological data of the target icing mountain area based on the micro-scale corrected air temperature distribution field of the wire height layer, the micro-scale corrected wind speed distribution field of the wire height layer and the correction results of other meteorological element distribution fields of the wire height layer; Wherein the other meteorological elements include at least relative humidity and precipitation related variables.
  10. 10. The method of claim 9, further comprising, after extracting the microtopography factor of the transmission line corridor area from the base dataset: dividing the power transmission line into a plurality of line segments; for each line segment, constructing a buffer area of the line segment, and taking statistics of each micro-topography factor in the buffer area as the micro-topography factor of the line segment; Correspondingly, before the local micro-scale topography effect correction is carried out on the mesoscale distribution field of each meteorological element of the wire height layer by utilizing the micro-topography factors, the method further comprises the following steps: Mapping the mesoscale distribution field of each meteorological element of the wire height layer to each line segment through spatial interpolation to obtain the mesoscale distribution field of each line segment in each meteorological element of the wire height layer.
  11. 11. The method of claim 10, wherein each meteorological element mesoscale distribution field of the wire level layer further comprises a mesoscale liquid water content distribution field of the wire level layer; The liquid water content distribution field of the wire height layer is determined based on the air temperature distribution field of the wire height layer, the relative humidity distribution field of the wire height layer and the precipitation related variable distribution field of the wire height layer; correspondingly, the high space-time resolution analysis meteorological data also comprises a correction result of a liquid water content distribution field of the wire height layer; the correction result of the liquid water content distribution field of the wire height layer is determined based on the correction result of the air temperature distribution field of the wire height layer after microscale correction, the correction result of the relative humidity distribution field of the wire height layer and the correction result of the precipitation related variable distribution field.
  12. 12. The method of claim 11, wherein the diagnostic model of the liquid water content distribution field of the wire level layer is as follows: Wherein, the A wire height layer liquid water content diagnostic value at time t for line segment k; a scaling factor diagnostic for liquid water content; Precipitation related variables for the wire height layer of line segment k at time t; wire height layer relative humidity at time t for line segment k; wire height air temperature at time t for line segment k; the relative humidity weight function is used for representing the influence degree of different humidity on the liquid water content; the temperature weight function is used for representing the influence degree of different temperatures on the supercooled liquid water.
  13. 13. The method of claim 1 or 7, further comprising, prior to performing the dynamic downscaling simulation: Based on the basic data set re-analysis meteorological data, calculating an average meteorological field of each time period, and decomposing the re-analysis meteorological data of any moment in the basic data set into the sum of the average meteorological field and abnormal meteorological quantity of the corresponding time period; and carrying out space-time smoothing on the abnormal weather quantity, and obtaining smoothed and analyzed weather data based on the smoothed abnormal weather quantity and an average weather field of each time period.
  14. 14. The method of claim 1, wherein constructing a transmission line icing and analysis database based on the microtopography factors and high space-time resolution and analysis meteorological data for the target icing region comprises: And using a data model with a preset first format, and using a space grid unit and a time step as indexes to store the micro-terrain factors and the high space-time resolution and analyze meteorological data in a layered manner.
  15. 15. The method of claim 10, wherein constructing a transmission line icing and analysis database based on the microtopography factors and high space-time resolution and analysis meteorological data for the target icing region comprises: And using a data model with a preset second format, and using line segments and time steps as indexes to store the micro-terrain factors and the high space-time resolution analytical meteorological data in a layered manner.
  16. 16. The method of claim 1, further comprising, after constructing the transmission line icing analysis database: If the updating of the original re-analysis meteorological data is monitored, performing dynamic downscaling simulation, vertical gradient correction and local microscale topographic effect correction on the updated re-analysis meteorological data to obtain high space-time resolution meteorological updated data; and updating the icing analysis database of the power transmission line based on the high space-time resolution meteorological update data.
  17. 17. The utility model provides a little topography micro-meteorological transmission line icing analysis database construction system which characterized in that includes: the preprocessing module is used for carrying out space-time alignment on the acquired original Digital Elevation Model (DEM) data of the complex mountain area and the original analysis meteorological data to obtain a basic data set; the downscaling module is used for performing dynamic downscaling simulation by taking the analysis meteorological data in the basic data set as a large-scale background field and boundary conditions and the DEM data in the basic data set as a terrain forced field to obtain a mesoscale meteorological field of a target icing mountain area; the vertical correction module is used for carrying out vertical gradient correction on the actual height of the power transmission line on the mesoscale gas image field based on boundary layer theory to obtain mesoscale distribution fields of all meteorological elements of the wire height layer; The micro-scale correction module is used for extracting micro-topography factors of the corridor area of the transmission line from the basic data set, carrying out local micro-scale topography effect correction on each meteorological element mesoscale distribution field of the wire height layer by utilizing the micro-topography factors, and generating high space-time resolution analysis meteorological data of a target icing mountain area; And the construction module is used for constructing an ice coating analysis database of the power transmission line based on the micro-topography factors and the high space-time resolution analysis meteorological data of the target ice coating mountain area.
  18. 18. The system of claim 17, wherein the micro-topography factors include at least grade, slope, topography relief, topography shielding, and wind corridor index; The terrain shielding degree is used for representing windward/leeward characteristics of each spatial position of the target icing mountain area in different directions; the wind porch index is used for representing the diversion and contraction effect of the terrain at each spatial position of the target icing mountain area on the wind field.
  19. 19. The system of claim 18, wherein the microscale modification module includes a topography factor extraction sub-module comprising: a shielding degree calculating subunit, configured to calculate, for a spatial position in a power transmission line corridor area of a target icing mountain area in the basic data set, a terrain shielding degree of the spatial position by performing terrain shielding scanning along a plurality of azimuth angles of the spatial position; And wind porch-path calculation subunit, configured to calculate, for a spatial position in a power transmission line corridor area of a target iceberg-covered area in the basic dataset, a wind corridor index of the spatial position based on a dominant wind direction and a topographic profile feature of the spatial position extracted from the basic dataset.
  20. 20. The system of claim 19, wherein the masking degree calculation subunit is specifically configured to: Taking the space position as the center, scanning the terrain upstream along a plurality of azimuth angles of the space position, and determining the height of a scanning point for shielding incoming wind and the horizontal distance between the scanning point and the space position; Determining a maximum shielding angle of the scanning point in the azimuth direction based on the height of the scanning point and the horizontal distance between the scanning point and the space position; and carrying out normalization processing on the maximum shielding angles in the azimuth directions to obtain the terrain shielding degree of the space position.

Description

Construction method and system of ice coating analysis database of micro-topography micro-meteorological transmission line Technical Field The invention relates to the technical field of disaster prevention and reduction of electric power systems and power grid meteorological application, in particular to a construction method and a construction system of an icing analysis database of a micro-topography micro-meteorological transmission line. Background The ice coating of the power transmission line is one of the most typical and most harmful meteorological disasters in the mountain areas in the south of China and in the frequent areas of ice, rain and snow. The ice coating can obviously increase dead weight and wind load of the wires and the hardware fittings, and cause a series of cascading failures such as wire galloping, strand breakage, wire breakage, hardware fitting damage, tower dumping, insulator flashover and the like, thereby further causing large-scale power failure and even power grid disconnection and seriously threatening safe and stable operation of the power grid and national economic activities. As the power grid is developed to high voltage, large capacity, long distance and mountain area depth, the proportion of the transmission line crossing the complex mountain area and canyon is continuously increased, and the exposure risk of icing disasters is also increased. At present, the power grid icing monitoring means still mainly depend on a limited number of weather observation stations, icing monitoring devices and manual line inspection, the space coverage is limited, the icing prediction accuracy and precision for complex mountain areas are low, and the power grid safe operation requirement is difficult to meet. Disclosure of Invention In order to solve the problem of low icing prediction accuracy and precision of the complex mountain area, the invention provides a construction method and a construction system of an icing analysis database of a micro-terrain microclimate transmission line. On one hand, the invention provides a construction method of an icing analysis database of a micro-topography micro-meteorological transmission line, which comprises the following steps: Carrying out space-time alignment on the acquired original Digital Elevation Model (DEM) data of the complex mountain region and the original analysis meteorological data to obtain a basic data set; Taking the analysis meteorological data in the basic data set as a large-scale background field and boundary conditions, and taking the DEM data in the basic data set as a terrain forcing field, performing dynamic downscaling simulation to obtain a mesoscale meteorological field of a target iceberg area; Performing vertical gradient correction aiming at the actual height of the power transmission line on the mesoscale gas image field based on boundary layer theory to obtain mesoscale distribution fields of all meteorological elements of the wire height layer; Utilizing the micro-topography factors to correct local micro-scale topography effect of each meteorological element mesoscale distribution field of the wire height layer, and generating high space-time resolution analysis meteorological data of a target icing mountain area; and constructing an ice coating analysis database of the power transmission line based on the micro-topography factors and the high space-time resolution analysis meteorological data of the target ice coating mountain area. Optionally, the micro-topography factors include at least a slope, a slope direction, a topography relief, a topography shielding degree, and a wind corridor index; The terrain shielding degree is used for representing windward/leeward characteristics of each spatial position of the target icing mountain area in different directions; the wind porch index is used for representing the diversion and contraction effect of the terrain at each spatial position of the target icing mountain area on the wind field. Optionally, the process for extracting the topographic shielding degree includes: For a space position in a power transmission line corridor area of a target icing mountain area in the basic data set, performing terrain shielding scanning along a plurality of azimuth angles of the space position, and calculating the terrain shielding degree of the space position; The extraction process of the wind corridor index comprises the following steps: For a spatial location within a transmission line corridor area of a target iceberg area in the base dataset, a wind corridor index for the spatial location is calculated based on a dominant wind direction and topographical profile features of the spatial location extracted from the base dataset. Optionally, calculating the terrain shielding degree of the spatial location by performing a terrain shielding scan along a plurality of azimuth angles of the spatial location includes: Taking the space position as the center, scanning the terrai