CN109130955B - High-speed railway dropper pre-allocation method for compensating influence of contact line abrasion - Google Patents
High-speed railway dropper pre-allocation method for compensating influence of contact line abrasion Download PDFInfo
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- 238000005299 abrasion Methods 0.000 title claims abstract description 54
- 238000000034 method Methods 0.000 title claims abstract description 34
- 239000000725 suspension Substances 0.000 claims abstract description 11
- 230000008859 change Effects 0.000 claims abstract description 7
- 238000012937 correction Methods 0.000 claims description 11
- 238000006073 displacement reaction Methods 0.000 claims description 9
- 210000000707 wrist Anatomy 0.000 claims description 6
- 230000000694 effects Effects 0.000 claims description 5
- 230000009471 action Effects 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 2
- 238000013459 approach Methods 0.000 abstract description 4
- 238000011900 installation process Methods 0.000 abstract 1
- 238000013461 design Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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- 230000009286 beneficial effect Effects 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60M—POWER SUPPLY LINES, AND DEVICES ALONG RAILS, FOR ELECTRICALLY- PROPELLED VEHICLES
- B60M1/00—Power supply lines for contact with collector on vehicle
- B60M1/12—Trolley lines; Accessories therefor
- B60M1/28—Manufacturing or repairing trolley lines
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Abstract
The invention provides a high-speed railway dropper pre-allocation method for compensating the influence of contact line abrasion, which takes 1/2 of the lifting amount of a suspension point of a contact line when the abrasion coefficient is the maximum acceptable value as the reserved sag of the suspension point in the one-time integral installation process of a contact line and comprises the following steps: (1) solving an initial equilibrium state model of the overhead line system; (2) preassembling a hanger; (3) calculating wear contact line parameters; (4) establishing a contact net abrasion calculation model; (5) calculating the lead height change value of the wear contact net; (6) and calculating to obtain the prearranged length of the catenary dropper. The invention reasonably sets the reserved sag of the suspension point of the contact line, so that the sag can gradually approach the ideal lead height after being worn, and then deviate from the ideal lead height again, thereby ensuring that the geometric smoothness fluctuation in the whole contact line service cycle deviates a small ideal value, and further obtaining better service performance and longer service life.
Description
Technical Field
The invention belongs to the field of electrified railways, and particularly relates to a high-speed railway dropper pre-allocation method for compensating the influence of contact line abrasion.
Background
At present, the networked operation of high-speed rails is realized in China, and a contact network is an important component of a traction power supply system of a high-speed railway. The use condition is harsh, and parts can inevitably generate abrasion after long-time operation, thereby causing the change of the structural state and the performance of the contact net. The contact wire bears the high-speed sliding friction of the pantograph slide plate and bears the mechanical and electrical dual loss. Following contact line wear, the lead height non-uniformity throughout the anchor segment deteriorates gradually and away from the initial design value. Considering the contact net performance in the whole service cycle, the research and compensation of the influence of the contact line abrasion on the contact net performance has great significance. The invention aims to provide a preassembling method for compensating contact line abrasion by a high-speed railway dropper, which reasonably increases the sag of a preset dropper to improve the geometric irregularity of a contact line caused by abrasion.
Disclosure of Invention
Aiming at the problems in the prior art, the technical scheme adopted by the invention for solving the problems in the prior art is as follows:
a high-speed railway dropper pre-allocation method for compensating the influence of contact line abrasion is characterized by comprising the following steps of:
step 1, solving an initial equilibrium state model of a contact network:
establishing an initial balance state model of the contact line on the basis of a split mode method, simulating the state of no abrasion of the contact line by the initial balance state model, and defining the conduction height of each dropper and positioner connecting part of the contact line as a standard value; solving the initial equilibrium state model of the contact network by using a finite element method, and calculating to obtain the initial equilibrium state model of the contact network without correction under the condition of ensuring the level of the contact line;
step 2, hanger preassembly:
according to the calculation result of the initial equilibrium state model, the standard preset length L of each hanger under the condition of not considering abrasion is obtained* i；
Step 3, calculating abrasion contact line parameters:
defining the initial total sectional area of the contact line as the sum of the constant area S' of the upper half part of the y axis of the transverse section of the contact line and the semi-circle area of which the radius of the lower half part of the y axis is R, and the abrasion area S of the contact line in the section direction is the area of an arc section with abrasion height of X;
the ratio of the abrasion area S in the contact line section direction to the initial total section area of the contact line is abrasion coefficient r, and the abrasion coefficient r is as follows:
wherein, the corresponding relation between the abrasion area S and the abrasion height X is related to the cross section shape of the contact line, and the relation formula is as follows:
wherein,
calculating the wear coefficient r of differentThe cross section shape of the contact line and relevant parameters thereof comprise: sectional area A of worn contact line and horizontal moment of inertia I of sectional areayAnd the lateral moment of inertia Iz；
Step 4, establishing a contact net abrasion calculation model:
the wear factor r calculated in step 3maxLower wear contact line parameters: cross-sectional area A, cross-sectional moment of inertia IyAnd IzUpdating the finite element model of the contact net established in the first step to obtain a contact net abrasion calculation model;
analyzing the contact net abrasion calculation model in the fourth step to obtain the height guiding and lifting quantity D of each dropper hanging point after the contact line is abradedi；
Step 6, calculating the prearranged length of the catenary dropper:
presetting the standard length L of each hanging string without correction* i(obtained by the second step of calculation), 1/2 with high lifting amount is taken as the reserved sag, and the preset length L of the catenary dropper is obtained by calculationi：
The initial equilibrium state model of the overhead line system in the step 1 is obtained by a modulus method, a negative sag method or a target function extreme value method.
The modeling in the step 1 by using a split-mode method is simplified as follows:
(1) the carrier cable and the contact line are simultaneously under the action of tension and gravity, have larger deformation and adopt a large displacement beam unit with linear density;
(2) the hanger has a unidirectional tension characteristic, and adopts a nonlinear cable unit with linear density;
(3) the positioner is simplified into a nonlinear spring unit and a centralized mass unit, the wire clamp and the central anchor knot are simplified into the centralized mass unit, and the support and the wrist arm are simplified into a hinged support without considering the influence of the support and the wrist arm.
The finite element method solving process in the step 1 is as follows: firstly, a contact line and a carrier cable are equivalent to a large displacement beam unit with linear density, and the suspension string force of the carrier cable under the condition of ensuring the level of the contact line is calculated by applying fixed constraint on a suspension string point of the carrier cable; secondly, applying a dropper force to the carrier cable, thereby determining the initial displacement of the carrier cable and the length of the dropper which meet the mechanical balance relation; and finally, obtaining the initial hanger prearranged length without abrasion correction.
The invention has the following advantages:
the invention reasonably sets the reserved sag of the suspension point of the contact line, so that the sag can gradually approach the ideal lead height after being worn, and then deviate from the ideal lead height again, thereby ensuring that the geometric smoothness fluctuation in the whole contact line service cycle deviates a small ideal value, and further obtaining better service performance and longer service life.
Drawings
FIG. 1 is a graph of the location of contact lines at different wear factors;
FIG. 2 is a graph of the contact line position at the center of the anchor section with different wear coefficients before correction (400-450m section), wherein the contact line height is 5300mm at the 0 position as the ordinate;
FIG. 3 is a graph of the height change of contact lines at different wear coefficients after correction;
FIG. 4 is a graph comparing the maximum values of the deviation of the heights of the original and wear-considered recipes;
FIG. 5 is a flow chart of a high speed railway dropper pre-assembly method for compensating for contact line wear effects;
FIG. 6 is a schematic diagram of contact line wear;
FIG. 7 is a cross-sectional comparison of contact lines for different wear factors;
wherein: s' is the constant area of the upper half part of the y axis of the contact line cross section, R is the semi-circle radius of the lower half part of the y axis, S is the wear area (shaded part) of the contact line cross section direction, and X is the wear height.
Detailed Description
The technical solution of the present invention is further described in detail by way of example with reference to the accompanying drawings, as shown in fig. 1-2, each line on the drawings represents the contact line position under different wear factors, the horizontal axis represents the distance along the line direction, and the vertical axis represents the contact line height. The allowable value of the height deviation of the contact line in a single anchor section is +/-30 mm, the allowable range of the height difference of the contact line between adjacent positioning points is 20mm, and the allowable range of the height difference of the contact line between adjacent dropper is 10 mm. When the abrasion coefficient is 0.2, the height deviation of the contact line in the anchor section is 32.62mm and exceeds the specified value by 30 mm; the height of the contact line of the adjacent dropper is 8.20mm, which is close to the specified value of 10 mm; the contact line height difference of adjacent positioning points is 1.74mm, and the variation is small.
As shown in fig. 3, for a hanger preparation scheme that takes into account wear, the height variation of the contact lines at different wear factors is plotted, with each line representing the contact line position at different wear factors. The horizontal axis is the distance along the line direction and the vertical axis is the contact line height. When the abrasion coefficient is 0, the contact line is not an approximate horizontal line any more, but is in a form of integral height downward movement and midspan position upward projection, and the geometric position deviation is within a specified value; when the abrasion coefficient is 0.2, the height deviation of the contact line in the anchor section is 18.97mm, and is within the specified value +/-30 mm; the height of the contact line of the adjacent dropper is 6.19mm and is less than the specified value of 10 mm; the height difference of the contact lines of adjacent positioning points is 0.33mm, and the variation is small.
FIG. 4 is a further comparison of the present invention to the hanger recipes of FIGS. 1 and 3, showing from FIG. 4 that the initial recipe leads the height gradually away from the initial design value as wear occurs; the pre-prepared scheme considering the abrasion leads the height to gradually approach the ideal value after the abrasion, deviates from the ideal value again, and finally keeps in the range of the upper deviation value and the lower deviation value.
From fig. 4, a flow chart of a high-speed railway dropper pre-assembly method for compensating the contact line abrasion effect, it can be seen that the specific flow of the method is as follows.
Firstly, solving an initial equilibrium state model of a contact network:
in the examples given in the present invention, the parameters of the contact net structure (as shown in table 1 below), the contact net wire and tension and the type of the integral dropper (as shown in table 2 below) are given.
TABLE 1 contact net construction parameters
TABLE 2 contact net wire and tension
On the basis of a modulus method, the method applies a finite element method to solve, and can obtain an accurate model. The following simplification is carried out during modeling by a split-mode method:
(1) the carrier cable and the contact line are simultaneously under the action of tension and gravity, have larger deformation and adopt a large displacement beam unit with linear density;
(2) the hanger has a unidirectional tension characteristic, and adopts a nonlinear cable unit with linear density;
(3) the positioner is simplified into a nonlinear spring unit and a centralized mass unit, the wire clamp and the central anchor knot are simplified into the centralized mass unit, and the support and the wrist arm are simplified into a hinged support without considering the influence of the support and the wrist arm.
The finite element method is solved as follows:
firstly, a contact line and a carrier cable are equivalent to a large displacement beam unit with linear density, and the suspension string force of the carrier cable under the condition of ensuring the level of the contact line is calculated by applying fixed constraint on a suspension string point of the carrier cable; secondly, applying a dropper force to the carrier cable, thereby determining the initial displacement of the carrier cable and the length of the dropper which meet the mechanical balance relation; and finally, obtaining the initial hanger prearranged length without abrasion correction.
Step two, preassembling a hanger:
the hanger preassembly under wear is not considered.
Thirdly, calculating the parameters of the abrasion contact line:
a table of calculated wear coefficients r and wear heights X (as shown in table 3 below) was established for contact wire type cumg.150 in the examples given in this invention.
TABLE 3 Table of calculated relationship between wear coefficient r and wear height X
The cross-sectional view of the worn contact line was updated from the wear height X described in table 3 above, as shown in fig. 7:
to this end, the wear factor r is obtained as the maximum acceptable value rmax(usually take r)maxMaximum wear contact line cross-sectional shape at 0.2) and its associated parameters.
Fourthly, establishing a contact net abrasion calculation model:
and (3) calculating the wear contact line parameters according to the third step: cross-sectional area A after wear, cross-sectional moment of inertia IyAnd IzEstablishing the wear factor rmaxAnd (5) calculating the abrasion of the contact net.
And fifthly, calculating the lead height change value of the wear contact net:
and solving the contact network abrasion calculation model in the fourth step to obtain the height guide and lifting amount of each dropper hanging point after the contact line is abraded, and drawing the contact line positions under different abrasion conditions (as shown in figure 1).
Sixthly, calculating the prearranged length of the catenary dropper:
and (3) taking 1/2 (obtained by the sixth step) with high lifting amount as the reserved sag, and calculating the catenary dropper preset length without correction.
And at this moment, according to the preset length of the dropper of the contact line obtained by the sixth step, reestablishing a calculation model of the contact line, and solving and obtaining the height guide and lifting amount of each dropper hanging point after the contact line is worn, so as to draw the height change of the position of the contact line under different wearing conditions after correction (as shown in fig. 3). In order to verify the beneficial effect of the invention, the maximum value of the deviation of the lead height of the original preset scheme (as shown in figure 1) and the preset scheme (as shown in figure 3) considering the abrasion is taken for comparison, and the result (as shown in figure 4) shows that the reserved sag of the suspension point of the contact line is reasonably set, so that the reserved sag can gradually approach the ideal lead height after the abrasion and then deviate from the ideal lead height again. The invention ensures that the geometric smoothness fluctuation in the whole service cycle of the contact network deviates less from an ideal value, thereby obtaining better service performance and longer service life.
The protective scope of the present invention is not limited to the above-described embodiments, and it is apparent that various modifications and variations can be made to the present invention by those skilled in the art without departing from the scope and spirit of the present invention. It is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Claims (4)
1. A high-speed railway dropper pre-allocation method for compensating the influence of contact line abrasion is characterized by comprising the following steps of:
step 1, solving an initial equilibrium state model of a contact network:
establishing an initial balance state model of the contact line on the basis of a split mode method, simulating the state of no abrasion of the contact line by the initial balance state model, and defining the conduction height of each dropper and positioner connecting part of the contact line as a standard value; solving the initial equilibrium state model of the contact network by using a finite element method, and calculating to obtain the initial equilibrium state model of the contact network without correction under the condition of ensuring the level of the contact line;
step 2, hanger preassembly:
according to the calculation result of the initial equilibrium state model, the standard preset length L of each hanger under the condition of not considering abrasion is obtained* i；
Step 3, calculating abrasion contact line parameters:
defining the initial total sectional area of the contact line as the sum of the constant area S' of the upper half part of the y axis of the transverse section of the contact line and the semi-circle area of which the radius of the lower half part of the y axis is R, and the abrasion area S of the contact line in the section direction is the area of an arc section with abrasion height of X;
the ratio of the abrasion area S in the contact line section direction to the initial total section area of the contact line is abrasion coefficient r, and the abrasion coefficient r is as follows:
wherein, the corresponding relation between the abrasion area S and the abrasion height X is related to the cross section shape of the contact line, and the relational expression is formula (2):
wherein,
calculating the shape of the cross section of the contact line and related parameters thereof under different wear coefficients r, wherein the parameters comprise: sectional area A of worn contact line and horizontal moment of inertia I of sectional areayAnd the lateral moment of inertia Iz；
Step 4, establishing a contact net abrasion calculation model:
the wear factor r calculated in step 3maxLower wear contact line parameters: cross-sectional area A, cross-sectional moment of inertia IyAnd IzUpdating the finite element model of the contact net established in the first step to obtain a contact net abrasion calculation model;
step 5, calculating a wear contact net lead height change value:
analyzing the contact net abrasion calculation model in the fourth step to obtain the height guiding and lifting quantity D of each dropper hanging point after the contact line is abradedi；
Step 6, calculating the prearranged length of the catenary dropper:
presetting the standard length L of each hanging string without correction* iTaking 1/2 with high lifting amount as reserved sag, and calculating to obtain preset length L of catenary dropperi：
2. A method of high speed railway dropper rigging to compensate for the effects of contact line wear as recited in claim 1, wherein: the initial equilibrium state model of the overhead line system in the step 1 is obtained by a modulus method, a negative sag method or a target function extreme value method.
3. A method of high speed railway dropper rigging to compensate for the effects of contact line wear as recited in claim 1, wherein: the modeling in the step 1 by using a split-mode method is simplified as follows:
(1) the carrier cable and the contact line are simultaneously under the action of tension and gravity, have larger deformation and adopt a large displacement beam unit with linear density;
(2) the hanger has a unidirectional tension characteristic, and adopts a nonlinear cable unit with linear density;
(3) the positioner is simplified into a nonlinear spring unit and a centralized mass unit, the wire clamp and the central anchor knot are simplified into the centralized mass unit, and the support and the wrist arm are simplified into a hinged support without considering the influence of the support and the wrist arm.
4. A method of high speed railway dropper rigging to compensate for the effects of contact line wear as recited in claim 1, wherein: the finite element method solving process in the step 1 is as follows: firstly, a contact line and a carrier cable are equivalent to a large displacement beam unit with linear density, and the suspension string force of the carrier cable under the condition of ensuring the level of the contact line is calculated by applying fixed constraint on a suspension string point of the carrier cable; secondly, applying a dropper force to the carrier cable, thereby determining the initial displacement of the carrier cable and the length of the dropper which meet the mechanical balance relation; and finally, obtaining the initial hanger prearranged length without abrasion correction.
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| CN110472325B (en) * | 2019-08-06 | 2020-05-22 | 中铁第一勘察设计院集团有限公司 | Contact line suspension three-dimensional rapid shape finding method based on static space position of contact line |
| CN112861310B (en) * | 2020-12-31 | 2022-02-08 | 西南交通大学 | Method and system for measuring tension of elastic sling of contact net |
| CN116309280A (en) * | 2022-12-16 | 2023-06-23 | 上海药明康德新药开发有限公司 | Lymphocyte labeling method and system |
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| CN102358212A (en) * | 2011-09-09 | 2012-02-22 | 中铁建电气化局集团南方工程有限公司 | Construction method of dropper in full-compensatory elastic chain type hanger in contact network of rapid transit railway |
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| JP4973108B2 (en) * | 2006-10-05 | 2012-07-11 | 株式会社明電舎 | Trolley wire wear measuring device |
| CN101337515B (en) * | 2008-01-29 | 2011-04-06 | 中铁四局集团有限公司 | Construction method for integral dropper of simple chain type suspension contact network of electrified railway |
| JP6450971B2 (en) * | 2015-01-30 | 2019-01-16 | 株式会社明電舎 | Trolley wire wear measuring device and trolley wire wear measuring method |
| CN105216655B (en) * | 2015-10-20 | 2017-05-10 | 铁道第三勘察设计院集团有限公司 | Preplanning method for integral dropper in elastic chain type suspension for overhead contact system |
| JP6557839B2 (en) * | 2016-05-11 | 2019-08-14 | 公益財団法人鉄道総合技術研究所 | Pantograph lift estimation method and apparatus, and pantograph lift compensation method and apparatus |
| CN106809056B (en) * | 2017-04-07 | 2019-05-10 | 中铁建大桥工程局集团第五工程有限公司 | Modern tram contact net falls the pre- equipped installation method of the built-in compensation device of top |
| CN107169183B (en) * | 2017-05-02 | 2019-05-10 | 武汉理工大学 | The dropper length correction method of five parabolic type easement curves |
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|---|---|---|---|---|
| RU2088434C1 (en) * | 1994-08-03 | 1997-08-27 | Управление Октябрьской железной дороги | Method of mounting and dismounting of electrified railway contact system |
| CN102358212A (en) * | 2011-09-09 | 2012-02-22 | 中铁建电气化局集团南方工程有限公司 | Construction method of dropper in full-compensatory elastic chain type hanger in contact network of rapid transit railway |
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