CN102840850B - Determination method of power transmission line actual lightning protection angle - Google Patents

Abstract

The invention relates to a determination method of a power transmission line actual lightning protection angle. The method consists of: first making use of an existing two-dimensional power transmission line corridor distribution map and a sea-level elevation map to conduct scanning and projection overlay analysis so as to obtain a three-dimensional power transmission line corridor distribution map, and determining the three-dimensional geographic coordinates all over a power transmission line, then making a vertical line to an arbitrary span section of the power transmission line, and determining the properties of an only plane according to two intersection lines in the space, thus obtaining an error plane of the lightning protection angle within the span section and its positive direction vector, then subjecting an included angle of the error plane positive direction vector and a rightarrow (Z) axis of a Cartesian coordinate system to inverse cosine calculation to obtain an error angle under the power transmission line error plane, and finally according to the relative position of three phase leads and a tower, carrying out error angle correction, thus obtaining the actual lightning protection angle of each phase lead. The method provided in the invention realizes remote, accurate, and rapid determination of the power transmission line actual lightning protection angle, and has very good operability and practicality.

Description

The assay method at the actual lightning protection of a kind of transmission line of electricity angle

Technical field

The invention belongs to lightening protection engineering technical field, relate in particular to definite method at the actual lightning protection of a kind of transmission line of electricity angle.

Background technology

Transmission line of electricity lightning protection angle refers to the angle of lightning conducter to outside transmission pressure; its value has a significant impact circuit thunderbolt rate; therefore in power industry code, have the clearly regulation to each electric pressure transmission line of electricity lightning protection angle, and actual track is also to require in accordance with regulations design and construction.But due to the complicated variety of power transmission line corridor landform; transmission line of electricity lightning protection angle is actual to be subject to the impact of landform and to change; if while now still using the series of parameters such as the lightning withstand level of the design load computational scheme at lightning protection angle; the result that must lead to errors, to line thunder protection, work causes serious impact.Therefore, how to obtain accurately and rapidly line thunder protection shielding angle and become one of line thunder protection work problem demanding prompt solution.

The method at the definite actual lightning protection of tradition angle is normally wanted reconnaissance trip landform; determine the degree of deviation of shielding angle according to the relation of line alignment and surrounding terrain; finally revising design load obtains; this method need to arrive scene and measure; expend a large amount of manpower and materials; and exist very large artificial subjective factor, often cause the precision of result lower.

In sum; because definite method at the actual lightning protection of transmission line of electricity angle exists above all deficiencies, have a strong impact on the theoretical counting accuracy of lightning outage rate, therefore; in power transmission line lightning shielding protection field, need a kind of method that can obtain accurately and rapidly line thunder protection shielding angle badly.

Summary of the invention

All deficiencies of determining that in order to overcome the actual lightning protection of traditional transmission line of electricity angle method exists, realize asking for of transmission line of electricity lightning protection angle accurately and rapidly, and the method that the present invention proposes mainly comprises the following steps:

Step 1: determine the residing geographic position of transmission line of electricity on three-dimensional map, that is: the two-dimensional line route footpath figure of the electric power line pole tower position coordinates containing useful GPS GPS location is obtained to raster image through scanning, again with absolute elevation data map projection Overlap Analysis: by the simulation to the geographical region multiple attribute of projection, find and definite position simultaneously with several geographical attributes, according to definite geographic coordinate, it is carried out to intersection computing, that is:

x∈A∩B (1)

In formula, x is transmission line of electricity somewhere geographic coordinate; A, B is respectively two-dimentional transmission line of electricity wire diameter figure and absolute elevation map.By intersection computing, obtain representing under three-dimensional map the basic grid cell four angular vertex coordinates in transmission line of electricity geographic position, represent geographic position everywhere, circuit corridor with basic grid cell, its precision is determined by the size of selected grid;

Step 2: determine transmission line of electricity lightning protection angle error plane and positive direction vector thereof; that is: the power transmission line corridor on three-dimensional map is got the part of path of arbitrary span; make the vertical line of this span at span any point; this vertical line and the determined plane of transmission line of electricity span section are the error plane at transmission line of electricity lightning protection angle in this span section; make the vertical line of error plane, get this vertical line and cartesian coordinate system axle clamp angle is the vertical line direction of acute angle for the positive direction vector of transmission line of electricity lightning protection angle error plane in this span section. acquiring method as follows:

The coordinate system of the three-dimensional map that utilization contains this transmission line of electricity geographical location information, determines the geographic coordinate on four summits of basic grid cell centered by span intersection point, and is designated as respectively its 3 d space coordinate can obtain by formula (2), the diagoned vector of the definite earth's surface elementary cell of basic grid cell 3 d space coordinate can try to achieve by formula (3), according to space analysis geometrical principle, pass through just can determine the spatial character of basic grid cell, calculate by formula (4) vector product can obtain the positive direction vector of transmission line of electricity lightning protection angle error plane

$\begin{array}{c}{\stackrel{\→}{P}}_{i,j}=(x_0+(i-1)*\mathrm{\Δx},y_0+(j-1)*\mathrm{\Δy},z_{i,j})\\ (i=\mathrm{1,2},...,M)\\ (j=\mathrm{1,2},...,N)\end{array}---\left(\text{2}\right)$

In formula, △ x, the base unit length that △ y is Raster Data Model; (x ₀, y ₀) be origin.

$\begin{array}{c}{\stackrel{\→}{a}}_{i,j}={\stackrel{\→}{P}}_{i+1,j+1}-{\stackrel{\→}{P}}_{i,j}=(\mathrm{\Δx},\mathrm{\Δy},z_{i+1,j+1}-z_{i,j})\\ {\stackrel{\→}{b}}_{i,j}={\stackrel{\→}{P}}_{i,j+1}-{\stackrel{\→}{P}}_{i+1,j}=(-\mathrm{\Δx},\mathrm{\Δy},z_{i,j+1}-z_{i+1,j})\end{array}---\left(3\right)$

In formula, for the diagoned vector of the definite earth's surface elementary cell of basic grid cell; for the geographic coordinate on four summits of basic grid cell centered by line span intersection point; △ x, the base unit length that △ y is Raster Data Model; z _i,j, z _{i+1, j}, z _{i, j+1}, z _{i+1, j+1}for four summits of the basic grid cell centered by line span intersection point exist coordinate on direction of principal axis.

$\begin{array}{c}\stackrel{\→}{n}={\stackrel{\→}{a}}_{\mathrm{ij}}\×{\stackrel{\→}{b}}_{\mathrm{ij}}=\left|\begin{array}{ccc}\stackrel{\→}{i}& \stackrel{\→}{j}& \stackrel{\→}{k}\\ x_a& y_a& z_a\\ x_b& y_b& z_b\end{array}\right|=\left|\begin{array}{ccc}\stackrel{\→}{i}& \stackrel{\→}{j}& \stackrel{\→}{k}\\ \mathrm{\Δx}& \mathrm{\Δy}& z_{i+1,j+1}-z_{i,j}\\ -\mathrm{\Δx}& \mathrm{\Δy}& z_{i,j+1}-z_{i+1,j}\end{array}\right|\\ =(\mathrm{\Δy}(z_{i,j+1}+z_{i,j}-z_{i+1,j+1}-z_{i+1,j}),-\mathrm{\Δx}(z_{i,j+1}+z_{i+1,j+1}-z_{i+1,j}-z_{i,j}),2\mathrm{\Δx\Δy})\\ (i=\mathrm{1,2},...,M)\\ (j=\mathrm{1,2},...,N)\end{array}---\left(4\right)$

In formula, for the positive direction vector of transmission line of electricity lightning protection angle error plane, for the diagoned vector of the definite earth's surface elementary cell of basic grid cell; be respectively coordinate x, y, the vector of unit length on z direction of principal axis; x _a, y _a, z _a, x _b, y _b, z _bbe respectively three dimensional space coordinate value; △ x, the base unit length that △ y is Raster Data Model; z _i,j, z _{i+1, j}, z _{i, j+1}, z _{i+1, j+1}for four summits of the basic grid cell centered by line span intersection point exist coordinate on direction of principal axis.

Step 3: ask for the error angle under transmission line of electricity lightning protection angle error plane.That is: the value of slope of definition transmission line of electricity lightning protection angle error plane is error angle.According to definition, error angle is the angle of error plane and surface level, and it is numerically equal to the error plane positive dirction that step 2 is tried to achieve in cartesian coordinate system the angle of axle, and this folder cosine of an angle equals with the business of the scalar product of direction of principal axis vector of unit length and the product of mould, so can be in the hope of the numerical value of this error angle, as shown in formula (5) by the cos operation of negating. $\begin{array}{c}\mathrm{slope}=\arccos \left(\frac{\stackrel{\→}{z}*\stackrel{\→}{n}}{\left|\stackrel{\→}{z}\right|*\left|\stackrel{\→}{n}\right|}\right)\\ =\arccos (2\mathrm{\Δx\Δy}/{({\left(\mathrm{\Δy}(z_{i,j+1}+z_{i,j}-z_{i+1,j+1}-z_{i+1,j})\right)}^2+{\left(\mathrm{\Δx}(z_{i,j+1}+z_{i+1,j+1}-z_{i+1,j}-z_{i,j})\right)}^2+4\mathrm{\Δ}{x}^2{\mathrm{\Δy}}^2)}^{\frac{1}{2}})\end{array}---\left(5\right)$

In formula, slope represents the error angle at transmission line of electricity lightning protection angle under this span.

Step 4: ask for the actual lightning protection of transmission line of electricity angle.That is: by consulting phase sequence figure and the shaft tower detail list under this span of transmission line of electricity, can determine that the line phase-sequence detection under this span distributes, if when certain phase conductor is positioned at the side that shaft tower and earth's surface angle are acute angle, the actual lightning protection angle of this phase conductor is that design load deducts the error angle under error plane; If when certain phase conductor is positioned at the side that shaft tower and earth's surface angle are obtuse angle, the actual lightning protection angle of this phase conductor is that design load adds the error angle under error plane.Repeating step 1 can be tried to achieve the lightning protection angle actual value in any span section of this transmission line of electricity to step 4.

The invention has the beneficial effects as follows, the method that the present invention proposes has realized the long-range method of determining accurately and rapidly the actual lightning protection of transmission line of electricity angle, has overcome the shortcoming that classic method error is large, waste time and energy, and has good operability and practicality.

Further set forth content of the present invention below in conjunction with drawings and Examples.

Brief description of the drawings

Fig. 1 is that process flow diagram is determined at the actual lightning protection of transmission line of electricity angle;

Fig. 2 is any span section of transmission line of electricity lightning protection angle error plane positive dirction schematic diagram;

Fig. 3 is the basic grid cell positive direction vector of transmission line of electricity lightning protection angle error plane schematic diagram;

Fig. 4 is transmission line of electricity lightning protection angle error angle schematic diagram.

Embodiment

Below by determining of the general horse transmission line of electricity of Yunnan 110kV 74#-75# span section lightning protection angle, to technical side of the present invention

Case is described further.

The first step: general 110kV horse transmission line of electricity is formed to two-dimensional coordinate map behind GPS location, then obtain through scanning the raster image that computing machine can be processed, again with the three-dimensional absolute elevation map projection Overlap Analysis of this area, find and definite transmission line of electricity position with identical latitude and longitude coordinates, according to the two-dimentional geographic coordinate of determining, it is carried out to intersection computing, obtain (as shown in Figure 2) transmission line of electricity three-dimensional geographic coordinate everywhere under three-dimensional map by formula (1).

Second step: as Fig. 2, appoint and get this transmission line of electricity span section as 74 ^#-75 ^#do the vertical line of this span section at three-dimensional coordinate map; the definite plane of vertical line and span section is the lightning protection angle error plane of this span section thus, in error plane, determines that the three-dimensional coordinate on four summits of the basic grid cell centered by intersection point is respectively as shown in Figure 3, try to achieve the diagoned vector of this grid cell by formula (3) 3 d space coordinate, be respectively (10 ,-10,1), (10 ,-10,1.667), recycling formula (4) compute vector vector product just can obtain the positive direction vector of transmission line of electricity lightning protection angle error plane in this span section for (6.67,26.67,200).

The 3rd step: the positive direction vector of utilizing transmission line of electricity lightning protection angle error plane in this span section having calculated in second step try to achieve this span section error cosine of an angle cosslope=0.99 by formula (5), then can calculate the error angle slope=8.1 ° of this span section by the method for the cosine of negating, as shown in Figure 4.

The 4th step: by consulting phase sequence figure and the shaft tower detail list of this span section of this article of transmission line of electricity, determine that this span section A, B, C three-phase are horizontal, A phase is limit phase conductor with C mutually, lightning protection angle design load is 15 °, wherein A phase conductor is positioned at the side that shaft tower and earth's surface angle are acute angle, and the actual lightning protection angle of A phase conductor is that design load deducts 15 °-8.1 °=6.9 ° of error angles; C phase conductor is positioned at the side that shaft tower and earth's surface angle are obtuse angle, and the actual lightning protection angle of C phase conductor is that design load adds 15 °+8.1 °=23.1 ° of error angles.Repeat the first step～four step and can try to achieve the lightning protection angle actual value of any span section of this transmission line of electricity.

Claims (1)

1. the assay method at the actual lightning protection of transmission line of electricity angle, is characterized in that, described method comprises the steps:

Step 1: determine the residing geographic position of transmission line of electricity on three-dimensional map, that is: the two-dimensional line route footpath figure of the electric power line pole tower position coordinates containing useful GPS GPS location is obtained to raster image through scanning, again with absolute elevation data map projection Overlap Analysis: by the simulation to the geographical region multiple attribute of projection, find and definite position simultaneously with several geographical attributes, according to definite geographic coordinate, it is carried out to intersection computing, that is:

x∈A∩B (1)

In formula, x is transmission line of electricity somewhere geographic coordinate; A, B is respectively two-dimentional transmission line of electricity wire diameter figure and absolute elevation map; By intersection computing, obtain representing under three-dimensional map the basic grid cell four angular vertex coordinates in transmission line of electricity geographic position, represent geographic position everywhere, circuit corridor with basic grid cell, its precision is determined by the size of selected grid;

Step 2: determine transmission line of electricity lightning protection angle error plane and positive direction vector thereof; that is: the power transmission line corridor on three-dimensional map is got the part of path of arbitrary span; make the vertical line of this span at span any point; this vertical line and the determined plane of transmission line of electricity span section are the error plane at transmission line of electricity lightning protection angle in this span section; make the vertical line of error plane, get this vertical line and cartesian coordinate system axle clamp angle is the vertical line direction of acute angle for the positive direction vector of transmission line of electricity lightning protection angle error plane in this span section; acquiring method as follows:

The coordinate system of the three-dimensional map that utilization contains this transmission line of electricity geographical location information, determines the geographic coordinate on four summits of basic grid cell centered by span intersection point, and is designated as respectively its 3 d space coordinate can obtain by formula (2), the diagoned vector of the definite earth's surface elementary cell of basic grid cell 3 d space coordinate can try to achieve by formula (3), according to space analysis geometrical principle, pass through just can determine the spatial character of basic grid cell, calculate by formula (4) vector product can obtain the positive direction vector of transmission line of electricity lightning protection angle error plane

$\begin{array}{c}{\stackrel{\→}{P}}_{i,j}=(x_0+(i-1)*\mathrm{\Δx},y_0+(j-1)*\mathrm{\Δy},z_{i,j})\\ (i=\mathrm{1,2},...,M)\\ (j=\mathrm{1,2},...,N)\end{array}---\left(\text{2}\right)$

In formula, △ x, the base unit length that △ y is Raster Data Model; (x ₀, y ₀) be origin;

$\begin{array}{c}{\stackrel{\→}{a}}_{i,j}={\stackrel{\→}{P}}_{i+1,j+1}-{\stackrel{\→}{P}}_{i,j}=(\mathrm{\Δx},\mathrm{\Δy},z_{i+1,j+1}-z_{i,j})\\ {\stackrel{\→}{b}}_{i,j}={\stackrel{\→}{P}}_{i,j+1}-{\stackrel{\→}{P}}_{i+1,j}=(-\mathrm{\Δx},\mathrm{\Δy},z_{i,j+1}-z_{i+1,j})\end{array}---\left(3\right)$

In formula, for the diagoned vector of the definite earth's surface elementary cell of basic grid cell; for the geographic coordinate on four summits of basic grid cell centered by line span intersection point; △ x, the base unit length that △ y is Raster Data Model; z _i,j, z _{i+1, j}, z _{i, j+1}, z _{i+1, j+1}for four summits of the basic grid cell centered by line span intersection point exist coordinate on direction of principal axis;

$\begin{array}{c}\stackrel{\→}{n}={\stackrel{\→}{a}}_{\mathrm{ij}}\×{\stackrel{\→}{b}}_{\mathrm{ij}}=\left|\begin{array}{ccc}\stackrel{\→}{i}& \stackrel{\→}{j}& \stackrel{\→}{k}\\ x_a& y_a& z_a\\ x_b& y_b& z_b\end{array}\right|=\left|\begin{array}{ccc}\stackrel{\→}{i}& \stackrel{\→}{j}& \stackrel{\→}{k}\\ \mathrm{\Δx}& \mathrm{\Δy}& z_{i+1,j+1}-z_{i,j}\\ \mathrm{\Δx}& \mathrm{\Δy}& z_{i,j+1}-z_{i+1,j}\end{array}\right|\\ =(\mathrm{\Δy}(z_{i,j+1}+z_{i,j}-z_{i+1,j+1}-z_{i+1,j}),-\mathrm{\Δx}(z_{i,j+1}+z_{i+1,j+1}-z_{i+1,j}-z_{i,j}),2\mathrm{\Δx\Δy})\\ (i=\mathrm{1,2},...,M)\\ (j=\mathrm{1,2},...,N)\end{array}---\left(4\right)$

In formula, for the positive direction vector of transmission line of electricity lightning protection angle error plane, for the diagoned vector of the definite earth's surface elementary cell of basic grid cell; be respectively coordinate x, y, the vector of unit length on z direction of principal axis; x _a, y _a, z _a, x _b, y _b, z _bbe respectively three dimensional space coordinate value; △ x, the base unit length that △ y is Raster Data Model; z _i,j, z _{i+1, j}, z _{i, j+1}, z _{i+1, j+1}for four summits of the basic grid cell centered by line span intersection point exist coordinate on direction of principal axis;

Step 3: ask for the error angle under transmission line of electricity lightning protection angle error plane, that is: the value of slope of definition transmission line of electricity lightning protection angle error plane is error angle; According to definition, error angle is the angle of error plane and surface level, and it is numerically equal to the error plane positive dirction that step 2 is tried to achieve in cartesian coordinate system the angle of axle, and this folder cosine of an angle equals with the business of the scalar product of direction of principal axis vector of unit length and the product of mould, so can be in the hope of the numerical value of this error angle, as shown in formula (5) by the cos operation of negating; $\begin{array}{c}\mathrm{slope}=\arccos \left(\frac{\stackrel{\→}{z}*\stackrel{\→}{n}}{\left|\stackrel{\→}{z}\right|*\left|\stackrel{\→}{n}\right|}\right)\\ =\arccos (2\mathrm{\Δx\Δy}/{({\left(\mathrm{\Δy}(z_{i,j+1}+z_{i,j}-z_{i+1,j+1}-z_{i+1,j})\right)}^2+{\left(\mathrm{\Δx}(z_{i,j+1}+z_{i+1,j+1}-z_{i+1,j}-z_{i,j})\right)}^2+4\mathrm{\Δ}{x}^2{\mathrm{\Δy}}^2)}^{\frac{1}{2}})\end{array}---\left(5\right)$

In formula, slope represents the error angle at transmission line of electricity lightning protection angle under this span;

Step 4: ask for the actual lightning protection of transmission line of electricity angle, that is: by consulting phase sequence figure and the shaft tower detail list under this span of transmission line of electricity, can determine that the line phase-sequence detection under this span distributes, if when certain phase conductor is positioned at the side that shaft tower and earth's surface angle are acute angle, the actual lightning protection angle of this phase conductor is that design load deducts the error angle under error plane; If when certain phase conductor is positioned at the side that shaft tower and earth's surface angle are obtuse angle, the actual lightning protection angle of this phase conductor is that design load adds the error angle under error plane; Repeating step 1 can be tried to achieve the lightning protection angle actual value in any span section of this transmission line of electricity to step 4.