CN-121998156-A - Early warning analysis method for extreme meteorological wind deviation flashover of power transmission line

CN121998156ACN 121998156 ACN121998156 ACN 121998156ACN-121998156-A

Abstract

The invention discloses an early warning analysis method for extreme meteorological wind deflection flashover of a power transmission line, which comprises the following analysis steps of S1, collecting information and meteorological data of the power transmission line, S2, calculating the maximum wind deflection angle of a suspension insulator of the power transmission line through a rigid straight rod model, S3, calculating the minimum air gap according to the maximum wind deflection angle, obtaining line wind deflection flashover voltage under the condition of corresponding gaps, S4, obtaining line wind deflection flashover probability based on the combination of the line wind deflection flashover voltage and line operation voltage, S5, evaluating the line wind deflection flashover risk based on the line wind deflection flashover probability, and giving early warning, wherein the method can accurately reflect the actual influence of a non-stable wind field and meteorological factors on the power transmission line, give out risk early warning, and ensure safe and stable operation of the power transmission line.

Inventors

JIANG SENYI
LIU YANG
QIN ZIQING
LIU SIYUAN
LIU SHUWEI
SU LING
BAI HAITAO
XU ZHIWEN
WANG XINKANG

Assignees

国网河南省电力公司商丘供电公司

Dates

Publication Date: 20260508
Application Date: 20251208

Claims (9)

1. The early warning and analyzing method for the extreme meteorological wind deflection flashover of the power transmission line is characterized by comprising the following analyzing steps of: s1, collecting information and meteorological data of a power transmission line; s2, calculating the maximum windage yaw angle of the line suspension insulator string through a rigid straight rod model; S3, calculating a minimum air gap according to the maximum windage yaw angle, and obtaining a line windage yaw flashover voltage under the condition of the corresponding gap; S4, obtaining a line windage flashover probability based on the line windage flashover voltage and the line operation voltage; And S5, evaluating the risk of the windage yaw flashover of the line based on the windage yaw flashover probability of the line, and giving out early warning.
2. The method for pre-warning and analyzing the extreme meteorological wind deviation flashover of the power transmission line according to claim 1, wherein the power transmission line information in the step S1 comprises power transmission line structure information and space coordinate information, and the meteorological data comprises wind speed, wind direction, air pressure, temperature, humidity and precipitation corresponding to the position of the power transmission line.
3. The method for pre-warning and analyzing the extreme meteorological wind deflection flashover of the power transmission line according to claim 1, wherein the calculation formula of the wind deflection angle in the step S2 is expressed as follows: Wherein: 、 respectively represents the horizontal load and the vertical load of the insulator string and the hardware fitting thereof, 、 Representing the horizontal and vertical loads of the wire, respectively.
4. The method for early warning and analyzing the extreme meteorological wind deflection flashover of the power transmission line according to claim 3, wherein the horizontal load and the vertical load of the insulator string and the hardware fitting thereof in the step S2 are respectively expressed as follows: , Wherein: represents the vertical wind pressure applied to the insulator chain and the hardware fitting thereof in unit area, Represents the air density, and the standard value is , Represents the wind speed in the direction perpendicular to the reference altitude, Representing the coefficient of variation of the altitude of the wind pressure, Represents the whole windward area of the insulator string and the hardware fitting thereof, Indicating the angle between the wind direction and the wire or ground direction.
5. The method for pre-warning and analyzing the extreme meteorological wind deflection flashover of the power transmission line according to claim 3, wherein the horizontal load and the vertical load of the wire in the step S2 are respectively expressed as follows: , Wherein: indicating the number of split conductors to be split, The wind load of the line unit length of the lead in the horizontal direction is shown, 、 Represents the horizontal span at two sides of the tower, 、 Respectively represent the height difference angle between the line pole tower and the adjacent pole tower, Indicating the horizontal tension of the wire, The line rotation angle is indicated, Respectively represent the complementary angles of the included angles of the transmission line and the cross arm, Representing the weight per unit length of wire, 、 Representing the height difference between adjacent towers, wherein the wind load of the line unit length of the lead in the horizontal direction is Wherein: Indicating the non-uniformity coefficient of the wind pressure, Represents the vertical wind pressure applied to the insulator chain and the hardware fitting thereof in unit area, Representing the coefficient of variation of the altitude of the wind pressure, Representing the body form factor of the wire, Indicating the overall outer diameter of the wire, Indicating the coefficient of increase of the horizontal wind load of the wire after icing.
6. The method for pre-warning and analyzing the extreme meteorological wind-bias flashover of the power transmission line according to claim 1, wherein the minimum air gap calculation formula in the step S3 is expressed as follows: Wherein: Representing the distance from the suspension point a to the tower centerline, Indicating the length of the string of insulators, Indicating the wire break-up radius, Represents the windage yaw angle of the insulator string, The included angle between the tower and the cross arm is shown, Representing the distance from the suspension point C to the tower centerline.
7. The method for early warning and analyzing the extreme meteorological wind deflection flashover of the power transmission line according to claim 1, wherein the step S3 is characterized in that the line wind deflection flashover voltage under the standard working condition is corrected by adopting air density, humidity and precipitation, and the air density correction coefficient is expressed as follows: , The air density correction index is indicated as such, Indicating the relative air density of the air in the air-bearing chamber, , , 、 The real-time air pressure and temperature respectively, and the humidity correction coefficient is expressed as: , indicating the humidity correction index (f) is provided, , Indicating the relative air density of the air in the air-bearing chamber, The absolute humidity is indicated as such, And fitting rainfall correction coefficients sequentially under different rainfall intensities by adopting a Gaussian formula, wherein the specific expression is as follows: and the corrected line windage flashover voltage is expressed as: , And The line windage flashover voltage after and before correction respectively.
8. The method for pre-warning and analyzing the extreme meteorological wind-bias flashover of the power transmission line according to claim 1, wherein the probability of the line wind-bias flashover in the step S4 is expressed as follows: Wherein: Representing the operating voltage of the line, Indicating the line windage flashover voltage, Represents the standard deviation, taking 10%, Representing a standard normal distribution.
9. The method for early warning and analyzing the extreme meteorological wind deflection flashover of the power transmission line is characterized in that the risk level of the line wind deflection flashover in the step S5 comprises safety, low risk, medium risk and high risk, wherein the risk level is safe when the line wind deflection flashover probability is less than 30%, the risk level is low when the line wind deflection flashover probability is more than or equal to 30% and less than 60%, the risk level is medium risk when the line wind deflection flashover probability is more than or equal to 60% and less than 90%, and the risk level is high risk when the line wind deflection flashover probability is more than or equal to 90%.

Description

Early warning analysis method for extreme meteorological wind deviation flashover of power transmission line Technical Field The invention belongs to the technical field of wind deflection flashover analysis of power transmission lines, and particularly relates to a power transmission line extreme weather wind deflection flashover early warning analysis method. Background In recent years, extreme weather such as strong wind caused by cold and tide in winter and strong convection in spring frequently accompanies a non-stationary wind field, the non-stationary wind field is represented as instantaneous jump of wind speed, the lead is subjected to the action of pulsating wind pressure to generate inertial swinging, and the lead is covered with ice in winter rain, so that the suspension insulator string is extremely easy to deflect to a large extent, further the wind deflection angle and wind response of a line are influenced, even flashover accidents are induced, and the safe and stable operation of a power grid is seriously threatened. Due to the lack of an accurate windage yaw calculation model and an early warning means, when equipment damage occurs to the power transmission line under the conditions of abnormal windage yaw, uneven stress of an insulator string and the like, the risk of power grid faults is increased, and regional power supply and social economy are seriously affected. Therefore, in order to solve the above problems, it is necessary to develop a method for early warning and analyzing the extreme weather windage yaw flashover of the power transmission line. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a power transmission line extreme weather wind deviation flashover early warning analysis method which accurately reflects the actual influence of a non-stationary wind field and a weather factor on a power transmission line, and gives out risk early warning to ensure the safe and stable operation of the power transmission line. The invention aims to realize the early warning analysis method for the extreme meteorological wind deflection flashover of the power transmission line, which comprises the following analysis steps: s1, collecting information and meteorological data of a power transmission line; s2, calculating the maximum windage yaw angle of the line suspension insulator string through a rigid straight rod model; S3, calculating a minimum air gap according to the maximum windage yaw angle, and obtaining a line windage yaw flashover voltage under the condition of the corresponding gap; S4, obtaining a line windage flashover probability based on the line windage flashover voltage and the line operation voltage; And S5, evaluating the risk of the windage yaw flashover of the line based on the windage yaw flashover probability of the line, and giving out early warning. Further, the power transmission line information in the step S1 includes power transmission line structure information and space coordinate information, and the meteorological data includes wind speed, wind direction, air pressure, temperature, humidity and precipitation corresponding to the position of the power transmission line. Further, in the step S2, the stroke offset angle calculation formula is expressed as: Wherein: 、 respectively represents the horizontal load and the vertical load of the insulator string and the hardware fitting thereof, 、Representing the horizontal and vertical loads of the wire, respectively. Further, the horizontal load and the vertical load of the insulator string and the hardware fitting thereof in the step S2 are respectively expressed as:, Wherein: represents the vertical wind pressure applied to the insulator chain and the hardware fitting thereof in unit area, Represents the air density, and the standard value is,Represents the wind speed in the direction perpendicular to the reference altitude,Representing the coefficient of variation of the altitude of the wind pressure,Represents the whole windward area of the insulator string and the hardware fitting thereof,Indicating the angle between the wind direction and the wire or ground direction. Further, the horizontal load and the vertical load of the wire in the step S2 are respectively expressed as:, Wherein: indicating the number of split conductors to be split, The wind load of the line unit length of the lead in the horizontal direction is shown,、Represents the horizontal span at two sides of the tower,、Respectively represent the height difference angle between the line pole tower and the adjacent pole tower,Indicating the horizontal tension of the wire,The line rotation angle is indicated,Respectively represent the complementary angles of the included angles of the transmission line and the cross arm,Representing the weight per unit length of wire,、Representing the height difference between adjacent towers, wherein the wind load of the line unit length of the lead in the horizont