CN101859996B - Method for iron tower anti-lead galloping of coupled system of iron tower, lead and anti-galloping device - Google Patents

Abstract

The invention discloses a method for iron tower anti-lead galloping of a coupled system of an iron tower, leads and an anti-galloping device. The method comprises the following steps: establishing an iron tower model; setting a lead galloping parameter; establishing a coupled system module of the iron tower, the leads and the anti-galloping device; adding an iron tower node load; setting tower foot node restraining; calculating and solving by utilizing a core calculation module; utilizing a post processing module to directly calculate to output an internal force-time course curve of an iron tower unit; checking the bearing capacity of the iron tower unit according to the calculated output internal force-time course curve of the iron tower unit; and judging whether the iron tower unit needs to be reinforced. The invention considers the coupling effect of the iron tower, the leads and anti-galloping device, accurately studies the lead galloping regulation after the weapon is additionally arranged, can calculate and analyze the influence of lead galloping on the iron tower, studies the bearing capacity of iron tower galloping resistance, provides a basis for reinforcing the iron tower unit, and can satisfy the requirements of scientific research and engineering design.

Description

The method of steel tower, wire, the anti-conductor galloping of anti-dance device coupled system steel tower

Technical field

The present invention relates to a kind of method of steel tower, wire, the anti-conductor galloping of anti-dance device coupled system steel tower.

Background technology

Conductor galloping is the solid coupling nonlinear vibration of stream that ice coating wire produces under the excitation of relatively stable wind.

It is large that ice coating wire is waved amplitude, longer duration, and harm is large.Gently alternate flashover, damage wire, gold utensil, heavy cause the accidents such as line tripping power failure, wire breaking and tower falling, cause heavy economic losses.The accident that the southern ice damage of 2008 destroys because of conductor galloping with regard to many iron tower of power transmission line occurring.Conductor galloping has contingency on time and space, be difficult to observation.The country that takes place frequently is waved by China, and conductor galloping becomes one of key factor that threatens the overhead transmission line safe and stable operation.

Since the thirties in 20th century, some scholars to conductor galloping mechanism, wave rule and done a large amount of research, proposed the multiple mechanism theory of waving, eccentric inertia coupling instability mechanism, fitful wind that mechanism, P.Yu are waved in the torsion of vertically waving mechanism, O.Nigol that comprises Den Hartog bring out mechanism etc.Chinese scholars has also been done a large amount of experimental studies to waving of wire, has proposed some effectively and the anti-dance measure that has found application in engineering practice.

The research of waving in the past is conceived to conductor galloping itself more, and steel tower is approximately certain spring supporting border, and this research method has following shortcoming: (1), do not consider the coupling effect between steel tower, wire, anti-dance device; (2), do not consider adjacent shelves wire intercoupling, influencing each other in the process of waving; (3), ice coating wire waves on the impact of iron tower of power transmission line research seldom, the safety research under the condition of waving of steel tower is seldom mentioned.

Therefore, consider the coupling effect between steel tower, wire, anti-dance device in the process of research conductor galloping, promote design theory and the level of the anti-conductor galloping of electric power pylon, improve the anti-dance bearing capacity of steel tower, become a very important job for convenience of calculating and engineering design service.

Summary of the invention

The research that the object of the invention is to overcome above-mentioned existing conductor galloping is not considered the coupling effect of wire and steel tower and anti-dance device, only steel tower is approximately the deficiency on certain spring supporting border; And provide a kind of method of steel tower, wire, the anti-conductor galloping of anti-dance device coupled system steel tower.

The present invention utilizes three-dimensional large displacement, large rotation, Nonlinear dynamic explicit Finite Element Method to calculate the process of waving of ice coating wire, set up steel tower, wire, anti-dance device coupling model, consider the coupling effect of steel tower and wire and anti-dance device, what wire after anti-dance device was installed in computational analysis additional waves rule and the stress of steel tower under the conductor galloping effect, in order to the anti-dance bearing capacity of steel tower is carried out safety evaluation.Can realize steel tower, wire, anti-dance device Fourier Series expansion technique rapid modeling, wave the output of computational analysis and result of calculation, but animation shows the overall process of conductor galloping, with the time history curve of figure, textual form output lead end tension force and the time history curve of iron tower construction member internal force, as the foundation of the anti-dance design of steel tower.

The objective of the invention is to reach by following measure: the method for steel tower, wire, the anti-conductor galloping of anti-dance device coupled system steel tower is characterized in that it comprises the steps:

(1), set up iron tower model: import the three-dimensional pylon line model of .dxf that vertical type steel tower internal force analysis software TTA generates, with in the .dxf of pylon wired information be converted into the unit information of FEM (finite element) model, the position with determining unit in the space; The size in each cross section, unit in the FEM (finite element) model that has generated is carried out assignment or directly imported the .out destination file that TTA generates, and the definition unit type is beam element type or bar unit type; After the unit of pylon FEM (finite element) model sectional dimension and the location positioning in the space thereof, then to the cross section of beam element towards adjusting, make beam element cross-wise direction and actual conditions identical, namely obtain an iron tower model; Set up a plurality of iron tower model according to actual span, the corner number of degrees, tower position elevation according to the method described above again;

(2), the conductor galloping parameter is set: the conductor galloping parameter is set, comprises wire division number, division circular section radius, strain insulator string length, wire parameter, icing parameter, wind speed, initial angle of attack θ and aerodynamic coefficient on iron tower model; Cell type and the material properties of definition wire insulation substring, bundle conductor conductor spacer, wherein insulator string is defined as bar unit, and conductor spacer is defined as beam element;

Described wire parameter comprises section radius, steel core section area, aluminium stranded conductor area of section, Unit Weight, modulus of elasticity, the icing parameter is the ice covering thickness of semiellipse type long axis direction, and described aerodynamic coefficient is determined according to icing parameter, conductor cross-section, wind speed and initial angle of attack θ by wind tunnel experiment;

(3), set up steel tower, wire, anti-dance device coupling system model: add wire on the steel tower hanging point, and the stringing tension force of input lead and dividing elements quantity; Adopt two minutes iterative methods that the original shape of wire is calculated, make wire arrive the stable equilibrium after weight application and initial tension; Described initial tension T=0.25Tp, Tp are the Fracture Force of wire; Conductor spacer in adding mutually according to actual pitch in bundle conductor; Add anti-dance device according to engineering reality on bundle conductor, wave Calculation Simulation platform input anti-dance device size, weight and installation site by GTA;

(4), after setting up steel tower, wire, anti-dance device coupling system model, add the steel tower joint load, the column foot joint constraint is set, translational degree of freedom and the rotational freedom of column foot in X-axis, Y-axis, three directions of Z axis retrained the definition load curve; Setup times parameter: calculate concluding time and result of calculation output time interval, generate calculation document, utilize the core calculations module to calculate and find the solution;

(5), after calculating finishes, utilize post-processing module, the animation of waving that directly shows wire and pylon, by the track of waving in figure output lead arbitrary cross section, that utilizes that the wire modal displacement of output-time history opisometer calculates wire waves frequency, throw amplitude value; Directly calculate the internal force of output steel tower unit-time history curve;

(6), check the bearing capacity of steel tower unit according to the steel tower element force that calculates output-time history curve, judge accordingly whether the steel tower unit needs to strengthen.

In technique scheme, the method that in described (4) step, the calculating of core calculations module is found the solution is:

The first step: read steel tower, wire, anti-dance device coupling system model;

Second step: in 0＜t＜=200 second, Slow loading gravity and quiet wind load on wire;

In 200＜t＜=300 second, keep gravity and quiet wind load;

In 300＜t＜T second, add dynamic load, wherein T is the concluding time;

The 3rd step: obtain wire node coordinate, rotational angle, speed, acceleration, angular speed, angular acceleration by the dynamic calculation module;

The 4th step: calculate lead unit speed, acceleration, angular speed, angular acceleration and angle of attack variation according to the data in the 3rd step;

The 5th step: according to the data in the 4th step try to achieve lead unit suffered wave load;

The 6th step: divide load equally the lead unit node according to the data in the 5th step;

The 7th step: according to the data in the 6th step will divide equally load on the lead unit node add in second step at 300＜t＜T dynamic load of second;

The 8th step: the dynamic load that obtains according to the 7th step constantly carries out dynamic calculation again to next, enters for the 3rd step; Entered again for the 4th step, the 5th step, the 6th step, the 7th step, the so circulation of the 8th step;

The 9th step: with data record and the output that conforms to the output time of setting in the 3rd step.

In technique scheme, two minutes iterative methods of described definite wire original shape are:

Step 1: the shape of differentiate line under the balance of gravity and stringing tension force;

Step 2: the shape of trying to achieve is carried out conversion, with the coordinate difference of all nodes of wire and wire hitch point on duty upper one less than 1.0 coefficient η, form new wire shape;

Step 3: new wire shape is carried out gravitational load calculating, and obtain the wire Horizontal Tension under gravity;

Step 4: the Horizontal Tension that comparing calculation goes out and stringing tension force, if Horizontal Tension less than stringing tension force, reduction ratio η, on the contrary increase, this coefficient is determined according to dichotomy;

Step 5: repeating step 2 is to step 4, until Horizontal Tension equates with stringing tension force, during less than 50N, thinks equal when the difference absolute value, and the shape that obtain this moment is the wire original shape.

The present invention is by setting up steel tower, wire, anti-dance device coupling system model; Wire is applied wave load and carry out finite element method (fem) analysis; And utilize post-processing module, with animation, figure and text formatting output result of calculation.

The method of steel tower of the present invention, wire, the anti-conductor galloping of anti-dance device coupled system steel tower, considered the coupling effect of steel tower, wire, anti-dance device, the research of conductor galloping rule has more accuracy after anti-dance device to installing additional, the also impact of computable analysis conductor galloping on steel tower, the anti-bearing capacity of waving of research steel tower, the steel tower foundation that the unit is strengthened is provided, can satisfies the needs of scientific research, engineering design.

Description of drawings

Fig. 1 is that GTA waves Calculation Simulation platform master interface;

Fig. 2 is steel tower, wire, anti-dance device coupling system model figure;

Fig. 3 is the schematic cross-section of ice coating wire;

Fig. 4 is ice coating wire force diagram schematic diagram;

Fig. 5 is the flow chart of core calculations module of the present invention;

Fig. 6 is the curve chart of wire stretched wire in the present invention;

Fig. 7 is six-multiple conductor middle part node movement locus figure in steel tower, wire, anti-dance device coupling system model;

Fig. 8 is six-multiple conductor middle part modal displacement-time history curve in steel tower, wire, anti-dance device coupling system model;

Fig. 9 is that the six-multiple conductor anti-dance device is arranged schematic diagram.

Embodiment

Describe performance of the present invention in detail below in conjunction with accompanying drawing, but they do not consist of limitation of the invention, only for example.By explanation, advantage of the present invention will become more clear and easily understand simultaneously.

The method of steel tower of the present invention, wire, the anti-conductor galloping of anti-dance device coupled system steel tower is first to set up steel tower, wire, anti-dance device coupling system model, then the load that system is subject to is as excitation, response by the central difference method solving system in nonlinear dynamic finite element method, wave at last the post-processing module output result of calculation of Calculation Simulation platform by GTA, whole process is all waved in Calculation Simulation platform (separately applying for the computer software registration) at GTA and carried out, and is convenient, fast.

Fig. 1 is that GTA waves Calculation Simulation platform master interface, and the major function that GTA waves the Calculation Simulation platform is as follows: import the pylon model from the .dxf file; Importing steel tower unit sectional dimension from the .out file; The cross section that the steel tower unit is set towards; Set up single conductor, bundle conductor model; Add panel load and joint constraint, add the curve of load and setup times and control parameter; Calculate the original shape of single conductor, bundle conductor; The icing of single conductor, bundle conductor is waved calculating; The output of time history curve and the text output of steel tower element force; The output of time history curve and the text output of modal displacement; The animation of whole pylon displacement shows; The animation that track is waved in the arbitrary cross section of wire shows.

Fig. 2 is steel tower, wire, anti-dance device coupling system model figure, and two ends are strain tower, hangs a phase six-multiple conductor, span 400m.

Fig. 3 is the schematic cross-section of ice coating wire, has shown the ice covering thickness 4.0mm of wire steel core diameter 7.04mm, wire diameter 23.94mm, semiellipse type long axis direction in figure.

Fig. 4 is ice coating wire force diagram schematic diagram, and in figure: e is eccentric throw, G ₁Be icing gravity, G ₂Be wire gravity, the θ angle is the initial angle of attack,

Be wire y direction speed,

Be wire z direction speed, U is wind speed, and β is relative wind velocity and y angular separation, U _rBe the relative wind velocity that causes because of the wire translation, α is the angle of attack of relative wind velocity, F _L(x) be aerodynamic lift, F _D(x) be aerodynamic drag, M _A(x) be aerodynamic moment.

Fig. 6 is the curve chart of wire stretched wire in the present invention, and in figure, A, B are contour hitch point, and L is span, and the O point is wire catenary curve minimum point, and x is the horizontal range that the curve any point is ordered from O, h ₀Distance for O point and horizontal reference line.

Fig. 7 is six-multiple conductor middle part node movement locus figure in steel tower, wire, anti-dance device coupling system model, curve shown in figure is the movement locus of node in the middle part of six-multiple conductor, comprise since 0 constantly until calculate y, the z coordinate information of the interior nodes finish time, can find out, after adding anti-dance device, conductor galloping is take vertical direction as main, and horizontal direction is auxiliary.

Fig. 8 is six-multiple conductor middle part modal displacement-time history curve in steel tower, wire, anti-dance device coupling system model.In figure, U _x, U _y, U _zBe respectively node along x, y, z direction of principal axis and close the displacement of direction with U, in the time of can finding out conductor galloping, modal displacement is take the vertical direction displacement as main.

Fig. 9 is that the six-multiple conductor anti-dance device is arranged schematic diagram.

The method of steel tower of the present invention, wire, the anti-conductor galloping of anti-dance device coupled system steel tower, it comprises the steps:

(1), set up iron tower model: import the three-dimensional pylon line model of .dxf that vertical type steel tower internal force analysis software TTA generates, with in the .dxf of pylon wired information be converted into the unit information of FEM (finite element) model, the position with determining unit in the space; The size in each cross section, unit in the FEM (finite element) model that has generated is carried out assignment or directly imported the .out destination file that TTA generates, and the definition unit type is beam element type or bar unit type; After the unit of pylon FEM (finite element) model sectional dimension and the location positioning in the space thereof, then to the cross section of beam element towards adjusting, make beam element cross-wise direction and actual conditions identical, namely obtain an iron tower model; Set up a plurality of iron tower model according to actual span, the corner number of degrees, tower position elevation according to the method described above again;

(2), the conductor galloping parameter is set: the conductor galloping parameter is set, comprises wire division number, division circular section radius, strain insulator string length, wire parameter, icing parameter, wind speed, initial angle of attack θ and aerodynamic coefficient on iron tower model; Cell type and the material properties of definition wire insulation substring, bundle conductor conductor spacer, wherein insulator string is defined as bar unit, and conductor spacer is defined as beam element;

Described wire parameter comprises section radius, steel core section area, aluminium stranded conductor area of section, Unit Weight, modulus of elasticity, the icing parameter is the ice covering thickness of semiellipse type long axis direction, and described aerodynamic coefficient is determined according to icing parameter, conductor cross-section, wind speed and initial angle of attack θ by wind tunnel experiment;

(3), set up steel tower, wire, anti-dance device coupling system model: add wire on the steel tower hanging point, and the stringing tension force of input lead and dividing elements quantity; Adopt two minutes iterative methods that the original shape of wire is calculated, make wire arrive the stable equilibrium after weight application and initial tension; Described initial tension T=0.25Tp, Tp are the Fracture Force of wire; Conductor spacer in adding mutually according to actual pitch in bundle conductor; Add anti-dance device according to engineering reality on bundle conductor, wave Calculation Simulation platform input anti-dance device size, weight and installation site by GTA;

(4), after setting up steel tower, wire, anti-dance device coupling system model, add the steel tower joint load, the column foot joint constraint is set, translational degree of freedom and the rotational freedom of column foot in X-axis, Y-axis, three directions of Z axis retrained the definition load curve; Setup times parameter: calculate concluding time and result of calculation output time interval, generate calculation document, utilize the core calculations module to calculate and find the solution;

(5), after calculating finishes, utilize post-processing module, the animation of waving that directly shows wire and pylon, by the track of waving in figure output lead arbitrary cross section, that utilizes that the wire modal displacement of output-time history opisometer calculates wire waves frequency, throw amplitude value; Directly calculate the internal force of output steel tower unit-time history curve;

(6), check the bearing capacity of steel tower unit according to the steel tower element force that calculates output-time history curve, judge accordingly whether the steel tower unit needs to strengthen.

The method that in described (4) step, the calculating of core calculations module is found the solution is:

The first step: read steel tower, wire, anti-dance device coupling system model;

Second step: in 0＜t＜=200 second, Slow loading gravity and quiet wind load on wire;

In 200＜t＜=300 second, keep gravity and quiet wind load;

In 300＜t＜T second, add dynamic load, wherein T is the concluding time;

The 3rd step: obtain wire node coordinate, rotational angle, speed, acceleration, angular speed, angular acceleration by the dynamic calculation module;

The 4th step: calculate lead unit speed, acceleration, angular speed, angular acceleration and angle of attack variation according to the data in the 3rd step;

The 5th step: according to the data in the 4th step try to achieve lead unit suffered wave load;

The 6th step: divide load equally the lead unit node according to the data in the 5th step;

The 7th step: according to the data in the 6th step will divide equally load on the lead unit node add in second step at 300＜t＜T dynamic load of second;

The 8th step: the dynamic load that obtains according to the 7th step constantly carries out dynamic calculation again to next, enters for the 3rd step; Entered again for the 4th step, the 5th step, the 6th step, the 7th step, the so circulation of the 8th step;

The 9th step: with data record and the output that conforms to the output time of setting in the 3rd step.

In technique scheme, two minutes iterative methods of described definite wire original shape are:

Step 1: the shape of differentiate line under the balance of gravity and stringing tension force;

Step 2: the shape of trying to achieve is carried out conversion, with the coordinate difference of all nodes of wire and wire hitch point on duty upper one less than 1.0 coefficient η, form new wire shape;

Step 3: new wire shape is carried out gravitational load calculating, and obtain the wire Horizontal Tension under gravity;

Step 4: the Horizontal Tension that comparing calculation goes out and stringing tension force, if Horizontal Tension less than stringing tension force, reduction ratio η, on the contrary increase, this coefficient is determined according to dichotomy;

Step 5: repeating step 2 is to step 4, until Horizontal Tension equates with stringing tension force, during less than 50N, thinks equal when the difference absolute value, and the shape that obtain this moment is the wire original shape.

Accuracy and necessity below by the calculating of computational analysis comparative illustration original shape:

According to the method for the present invention's proposition original shape of determining and the original shape that is assumed to straight line, degree of speeding after adding carrying force and parabola theories solution compare, the stringing tension force of wire Horizontal Tension and setting compares, and accuracy and the necessity of the inventive method is described.

Stretched wire (wire) accounting equation based on parabola theories is:

$y={\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HSA00000139947200011.png,HSA00000139947200032.png"\; state="\{\{state\}\}">h</figure-callout>}}_0+\frac{x^2}{2!{\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HSA00000139947200011.png,HSA00000139947200032.png"\; state="\{\{state\}\}">h</figure-callout>}}_0}$

$S=x+\frac{x^3}{3!{\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HSA00000139947200011.png,HSA00000139947200032.png"\; state="\{\{state\}\}">h</figure-callout>}}_0^2}$

In formula, y is the ordinate of arbitrfary point, and S is that span mid point O is the wire physical length (as shown in Figure 5) between the point of x to abscissa,

H is the wire Horizontal Tension, and q is uniform load value (being the unit length wire weight when only being subjected to gravity).

Get single LGJ-300/40 wire (national standard), 400 meters spans, the two strain towers in two ends, stringing tension force and be 9.80665 meters of 24000 Ns, acceleration of gravity ²/ second (acceleration of gravity in dimension 20-40 ° zone, the corresponding Northern Hemisphere).

1, parabola theories

According to the parabola theories solution, the degree of speeding of above-mentioned wire is: 9.258 meters;

2, straight line original shape

Suppose that original shape is straight line, add the degree of speeding that obtains wire after carrying force and be: be 7.72 meters, less by 16.57% than Theory Solution; The Horizontal Tension that obtains is: 28774.1 Ns, than the stringing tension force large 19.89% of setting;

3, the original shape that calculates according to the inventive method

According to the inventive method, the original shape that calculates is for straight line, adds the degree of speeding that obtains wire after carrying force to be: 9.278 meters, than Theory Solution large 0.216%; The Horizontal Tension that obtains is: 23947.3 Ns, less by 0.22% than the stringing tension force of setting;

From being not difficult to find out, if the supposition original shape is straight line, not only degree of speeding is inaccurate after adding carrying force, and the Horizontal Tension of wire does not meet with stringing tension force yet; If carry out determining of original shape according to the inventive method, after adding carrying force, wire degree of speeding and Theory Solution error are only 0.216%, and the Horizontal Tension that obtains and stringing tension error are only 0.22%.Contrast can find out, the original shape computational methods that the present invention proposes not only are necessary, and that it calculates accuracy rate is also high.

The below describes the method for ice coating wire equivalence for single a kind of material and sectional dimension:

The equivalent area of ice coating wire and equivalent density calculate: actual ice coating wire forms (wire also can adopt other metal to make) by aluminium, steel, three kinds of materials of icing, therefore needing is single a kind of material and sectional dimension with the ice coating wire equivalence, calculates its equivalent area and equivalent density.

The wire equivalent area is:

The equivalent density of ice coating wire is:

ρ＝(M _calc+A _iceρ _ice)/A

In formula, A _iceBe the area of icing on the cross section, ρ _iceDensity for ice is taken as 897.6kg/m ³, M _CalcCalculated weight for the unit length wire.

The below describes the beam element that adopts in the core calculations module:

Use the discrete ice coating wire of Belytschko beam element in processing, this beam element is processed large rotation with the corotation technology, the distortion of beam is divided into rigid body translation, rotation and true strain, rigid body displacement does not produce strain, only have true strain just to produce strain, the large displacement and large ro-tation that is suitable for the process of waving of wire is processed.

The below describes the static load in the core calculations module:

The static load of wire includes gravity and wind carries the two large divisions.The deadweight of wire can be given by the whole acceleration along gravity direction, and the quiet wind load of wire can obtain by following formula.

Quiet wind load expression formula:

$\left\{\begin{array}{c}{F}_L\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{U}^{2}d{C}_L\left(\mathrm{\&alpha;}\right)\\ F_D\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{U}^{2}d{C}_D\left(\mathrm{\&alpha;}\right)\\ M_A\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{U}^2{d}^2{C}_M\left(\mathrm{\&alpha;}\right)\end{array}\right.$

In formula, U is wind speed, and α is the angle of attack, and aerodynamic coefficient is got the value of wind tunnel experiment, ρ in formula _airBe atmospheric density, d is diameter of wire, F _L(x), F _D(x) and M _A(x) be respectively wire in aerodynamic lift, aerodynamic drag and the aerodynamic moment at x place.

Because GTA Calculation Simulation platform is dynamic Explicit Analysis method, for as far as possible accurately analog conducting wire carry at quiet wind, poised state under Action of Gravity Field, by Slow loading load and the final method of load a period of time that keeps, the static balance state is calculated.

After calculating quiet wind under certain wind speed and the initial angle of attack according to following formula and carrying, by the method for Slow loading, quiet wind is carried on the node that loads on wire.This loading procedure is calculated 200s (s represents second) altogether, and the every 1.0s of load increases by 0.5%, becomes 100% in 200s moment load; Kept afterwards for 100% load 100s time, make the scope of wire fluctuation within the acceptable scope; At 300s constantly, cancel Jing Fengzai, and replace with dynamically waving load, begin afterwards dynamically to wave calculating.

The below describes the load of dynamically waving in the core calculations module:

Dynamically wave load refers to that ice coating wire bears when waving load, comprise wire gravity, icing gravity and inertia force, the inertia torque that produces when the eccentric torque that eccentric icing causes and icing motion, and dynamic wind load (comprising the aerodynamic lift, aerodynamic drag and the aerodynamic moment that are produced by wind).

Under wind action, wire can be subject to vertically, level and twisting action power (showing as Fig. 4), and the size of these active forces and conductor length are linear relationship, and the aerodynamic lift of supposing unit length is F _L(x), aerodynamic drag is F _D(x) and aerodynamic moment be M _A(x), they are approximate along the distribution of x axle, and supposition is certainly normal usually, is expressed as:

$\left\{\begin{array}{c}{F}_L\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{(U-\stackrel{\&CenterDot;}{w})}^{2}d[\frac{C_L\left(\mathrm{\&alpha;}\right)}{\cos \mathrm{\&beta;}}-\frac{C_D\left(\mathrm{\&alpha;}\right)\tan \mathrm{\&beta;}}{\cos \mathrm{\&beta;}}]\\ F_D\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{(U-\stackrel{\&CenterDot;}{w})}^{2}d[\frac{C_L\left(\mathrm{\&alpha;}\right)\tan \mathrm{\&beta;}}{\cos \mathrm{\&beta;}}+\frac{C_D\left(\mathrm{\&alpha;}\right)}{\cos \mathrm{\&beta;}}]\\ M_A\left(x\right)=\frac{1}{2}{\mathrm{\&rho;}}_{\mathrm{air}}{(U-\stackrel{\&CenterDot;}{w})}^2{d}^2\frac{C_M\left(\mathrm{\&alpha;}\right)}{2{\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="HSA00000139947200042.png"\; state="\{\{state\}\}">cos</figure-callout>}}^2\mathrm{\&beta;}}\end{array}\right.$

ρ in formula _airBe atmospheric density, d is diameter of wire,

Be wire z direction speed, U is wind speed, and β is relative wind velocity and y angular separation, and α is the angle of attack of relative wind velocity, aerodynamic coefficient C _L(x), C _D(x) and C _M(x) can be determined by the wind tunnel experiment of corresponding ice type.

Comparison example: have, without the comparison of anti-dance device

In order to check the anti-dance effect of anti-dance device, foundation has, without two strain towers of anti-dance device-single-phase six-multiple conductor model (6 division LGJ-300/40 wires, 400 meters spans), calculated the wave situation of two kinds of models under 8m/s wind speed, 30 ° of initial angle of attack conditions.

Result of calculation:

A. time of experiencing in the wire stage of dancing is increased to 5000s from 800s, illustrates the formation that two parallel wielded-proof device can effectively suppress conductor galloping is installed;

B. the maximum amplitude of conductor galloping is reduced to 1.63m from 3.84m, reduces degree and reaches 60%, illustrates that two parallel wielded-proof device is installed has effectively reduced the amplitude of waving;

C. the frequency of conductor galloping becomes 20 beats/mins from 21-22 beats/min, illustrates the frequency of waving that two parallel wielded-proof device can change wire is installed.

By have in this example, without the contrast of the conductor galloping rule of anti-dance device, the method safety of steel tower of the present invention, wire, the anti-conductor galloping of anti-dance device coupled system steel tower is reliable, convenient and practical.

Claims (2)

1. the method for steel tower, wire, the anti-conductor galloping of anti-dance device coupled system steel tower, is characterized in that it comprises the steps:

(1), set up iron tower model: import the three-dimensional pylon line model of .dxf that vertical type steel tower internal force analysis software TTA generates, with in the .dxf of pylon wired information be converted into the unit information of FEM (finite element) model, the position with determining unit in the space; The size in each cross section, unit in the FEM (finite element) model that has generated is carried out assignment or directly imported the .out destination file that TTA generates, and the definition unit type is beam element type or bar unit type; After the unit of pylon FEM (finite element) model sectional dimension and the location positioning in the space thereof, then to the cross section of beam element towards adjusting, make beam element cross-wise direction and actual conditions identical, namely obtain an iron tower model; Set up a plurality of iron tower model according to actual span, the corner number of degrees, tower position elevation according to the method described above again;

(2), the conductor galloping parameter is set: the conductor galloping parameter is set, comprises wire division number, division circular section radius, strain insulator string length, wire parameter, icing parameter, wind speed, initial angle of attack θ and aerodynamic coefficient on iron tower model; Cell type and the material properties of definition wire insulation substring, bundle conductor conductor spacer, wherein insulator string is defined as bar unit, and conductor spacer is defined as beam element;

Described wire parameter comprises section radius, steel core section area, aluminium stranded conductor area of section, Unit Weight, modulus of elasticity, the icing parameter is the ice covering thickness of semiellipse type long axis direction, and described aerodynamic coefficient is determined according to icing parameter, conductor cross-section, wind speed and initial angle of attack θ by wind tunnel experiment;

(3), set up steel tower, wire, anti-dance device coupling system model: add wire on the steel tower hanging point, and the stringing tension force of input lead and dividing elements quantity; Adopt two minutes iterative methods that the original shape of wire is calculated, make wire arrive the stable equilibrium after weight application and initial tension; Described initial tension T=0.25Tp, Tp are the Fracture Force of wire; Conductor spacer in adding mutually according to actual pitch in bundle conductor; Add anti-dance device according to engineering reality on bundle conductor, wave by GTA and calculate anti-true platform input anti-dance device size, weight and installation site;

(4), after setting up steel tower, wire, anti-dance device coupling system model, add the steel tower joint load, the column foot joint constraint is set, translational degree of freedom and the rotational freedom of column foot in X-axis, Y-axis, three directions of Z axis retrained the definition load curve; Setup times parameter: calculate concluding time and result of calculation output time interval, generate calculation document, utilize the core calculations module to calculate and find the solution;

(5), after calculating finishes, utilize post-processing module, the animation of waving that directly shows wire and pylon, by the track of waving in figure output lead arbitrary cross section, that utilizes that the wire modal displacement of output-time history opisometer calculates wire waves frequency, throw amplitude value; Directly calculate the internal force of output steel tower-time history curve;

(6), check the bearing capacity of steel tower unit according to the steel tower element force that calculates output-time history curve, judge accordingly whether the steel tower unit needs to strengthen;

The method that in described (4) step, the calculating of core calculations module is found the solution is:

The first step: read steel tower, wire, anti-dance device coupling system model;

Second step: in 0＜t＜=200 second, Slow loading gravity and quiet wind load on wire;

In 200＜t＜=300 second, keep gravity and quiet wind load;

In 300＜t＜T1 second, add dynamic load, wherein T1 is the concluding time;

The 3rd step: obtain wire node coordinate, rotational angle, speed, acceleration, angular speed, angular acceleration by the dynamic calculation module;

The 4th step: calculate lead unit speed, acceleration, angular speed, angular acceleration and angle of attack variation according to the data in the 3rd step;

The 5th step: according to the data in the 4th step try to achieve lead unit suffered wave load;

The 6th step: divide load equally the lead unit node according to the data in the 5th step;

The 7th step: according to the data in the 6th step will divide equally load on the lead unit node add in second step at 300＜t＜T1 dynamic load of second;

The 8th step: the dynamic load that obtains according to the 7th step constantly carries out dynamic calculation again to next, enters for the 3rd step; Entered again for the 4th step, the 5th step, the 6th step, the 7th step, the 8th step, so circulation;

The 9th step: with data record and the output that conforms to the output time of setting in the 3rd step.

2. the method for steel tower according to claim 1, wire, the anti-conductor galloping of anti-dance device coupled system steel tower is characterized in that two minutes iterative methods of described definite wire original shape are:

Step 1: the shape of differentiate line under the balance of gravity and stringing tension force;

Step 2: the shape of trying to achieve is carried out conversion, with the coordinate difference of all nodes of wire and wire hitch point on duty upper one less than 1.0 coefficient η, form new wire shape;

Step 3: new wire shape is carried out gravitational load calculating, and obtain the wire Horizontal Tension under gravity;

Step 4: the Horizontal Tension that comparing calculation goes out and stringing tension force, if Horizontal Tension less than stringing tension force, reduction ratio η, on the contrary increase, this coefficient is determined according to dichotomy;

Step 5: repeating step 2 is to step 4, until Horizontal Tension equates with stringing tension force, during less than 50N, thinks equal when the difference absolute value, and the shape that obtain this moment is the wire original shape.

Images