CN107655513A - A kind of railway contact line dynamic monitor - Google Patents
A kind of railway contact line dynamic monitor Download PDFInfo
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- CN107655513A CN107655513A CN201610594244.6A CN201610594244A CN107655513A CN 107655513 A CN107655513 A CN 107655513A CN 201610594244 A CN201610594244 A CN 201610594244A CN 107655513 A CN107655513 A CN 107655513A
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- 238000004891 communication Methods 0.000 claims abstract description 8
- 230000006378 damage Effects 0.000 claims abstract description 8
- 238000005259 measurement Methods 0.000 claims abstract description 7
- 238000009434 installation Methods 0.000 claims abstract description 6
- 238000009825 accumulation Methods 0.000 claims abstract description 4
- 238000006073 displacement reaction Methods 0.000 claims description 9
- 238000012806 monitoring device Methods 0.000 claims description 8
- 238000005452 bending Methods 0.000 claims description 3
- 238000012360 testing method Methods 0.000 abstract description 2
- 238000001514 detection method Methods 0.000 description 11
- 230000003137 locomotive effect Effects 0.000 description 7
- 238000000034 method Methods 0.000 description 6
- 230000009471 action Effects 0.000 description 5
- 206010033799 Paralysis Diseases 0.000 description 3
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- 238000007689 inspection Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
- G01D21/00—Measuring or testing not otherwise provided for
- G01D21/02—Measuring two or more variables by means not covered by a single other subclass
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Abstract
The invention belongs to technical field of measurement and test, a kind of railway contact line dynamic monitor.Described device includes tension measuring system (1), Vibration-Measuring System (2), signal manifold (3), a set of tension measuring system (1) is installed respectively, a set of Vibration-Measuring System (2) is installed on transregional carrier cable (4) and dropper (5) bottom of contact line (6) respectively on the carrier cable (4) between the contact line (6) at railway contact line anchor section both ends and the clue compensation rope of carrier cable (4) are upper and transregional；The dynamic tension signal of installation site and the dynamic acceleration signal of three axial directions where tension measuring system (1) and Vibration-Measuring System (2) gather respectively, and sent by communication to signal manifold (3)；Signal manifold (3) utilizes the physical life of Miner linear damage accumulation theories, estimation contact line (6) and carrier cable (4).Provide a kind of high accuracy, real-time railway contact line dynamic monitor.
Description
Technical Field
The invention belongs to the technical field of testing, and discloses a dynamic monitoring device for a railway contact network.
Background
The overhead contact system is a special power transmission line installed over the high-speed railway line for supplying power to electric locomotives, is an important component of electrified traction power supply equipment, mainly comprises a contact line 6, a carrier cable 4, a dropper 5 and other large-scale flexible cables, is widely distributed on plains, mountains and mountains, is directly exposed to natural environments such as wind, snow, rain and dew, and is subjected to erosion of wind, frost, rain and snow and impact and vibration of a pantograph during high-speed operation all the year round, and the mechanical and electrical properties and states of the overhead contact system are dynamically changed, so that the operation environment is quite severe and has no reserve. The high-speed railway electrified train obtains driving electric energy through the contact of pantograph and contact net, and the contact net operating performance directly influences the stability of traction power supply system power supply and then directly influences the security of high-speed railway transportation.
According to railway field statistics, the most serious accidents of the contact network can be divided into the following situations, namely, the interaction between a locomotive pantograph and the contact network is a very complicated vibration system, when external force (such as locomotive pantograph traction force and wind force) acts on any point of the contact network, vibration waves can be generated on a lead, when the waves pass through a strut positioning suspension point or a dropper 5 point, all or part of the waves are reflected, the reflected waves are superposed on the transmitted waves, the contact line 6 is suspended on the dropper 5, the catenary 4 can also vibrate, and the vibration process becomes more complicated. The contact wire 6 can also vibrate up and down under the action of the lifting force of the pantograph under the condition of strong wind or during the operation of the train, so that the pantograph is damaged by being hit by other positioning devices due to the fact that the pull-out value or the height conduction is over, the damaged pantograph continues to operate, the contact net is seriously damaged, and the long-time paralysis of the electrified railway is caused;
and in the second situation, the contact network is a flexible system, and in the running process of the electric locomotive, the dynamic current collection of the pantograph and contact network coupling system generates a higher cyclic stress effect on the contact line 6, so that fatigue failure is easy to occur. The fatigue failure is brittle failure, has no obvious macroscopic deformation, and is easy to cause the disconnection of the contact line 6 and the paralysis of the electrified railway;
and thirdly, the tension of the contact wire 6 or the carrier cable 4 exceeds the range due to the failure of the anchor section tension adjusting device or the breakage of the dropper 5 and the like, so that the contact wire 6 is drilled below the pantograph head of the pantograph to cause a pantograph accident, the automatic pantograph lowering device does not act, the pantograph damages the contact network supporting device in a large scale, and the electrified railway is paralyzed for a long time.
In order to ensure the safe operation of the contact network system to the maximum extent, the working state and parameters of the contact network need to be measured to eliminate potential safety hazards, one of the common methods is manual on-site measurement along a line, and the method is poor in precision and low in efficiency and cannot meet the high-speed and high-density operation requirements of the modern electrified railway. The second common practice is to use automated overhead line inspection equipment, which is typically mounted on dedicated rail vehicles, such as a contact net detection vehicle, a rail detection vehicle, a comprehensive detection vehicle or a contact net operation vehicle, and the like, each railway administration department is responsible for scheduling, and periodically or aperiodically detecting a contact net, wherein the time interval of every two detections is short, namely one day, and long, namely a plurality of months, and the like, although relatively accurate contact net detection data can be obtained, the data is generally static parameter detection data, the surrounding environment of the line changes with time, such as wind direction, wind power, air temperature, humidity and the like, the measured data of cable tension and dynamic lifting amount are only the situation of the measuring moment, and the measured data of other moments can not be obtained, therefore, the actual running condition of the electric locomotive cannot be reflected, and the dynamic parameter detection data of the contact network during the running of the electric locomotive cannot be obtained.
Disclosure of Invention
The technical problems solved by the invention are as follows: the high-precision real-time dynamic monitoring device for the railway contact network is provided.
The technical scheme of the invention is as follows: the utility model provides a railway contact net dynamic monitoring device which characterized in that: the device comprises a tension measuring system 1, a vibration measuring system 2 and a signal collector 3, wherein a set of tension measuring system 1 is respectively arranged on a contact wire 6 at two ends of an anchor section of a railway contact network, a cable compensating rope of a catenary 4 and the catenary 4 in a span interval, and a set of vibration measuring system 2 is respectively arranged on the catenary 4 in the span interval and the bottom of a hanger 5 of the contact wire 6;
the tension measuring system 1 and the vibration measuring system 2 respectively collect dynamic tension signals and three axial dynamic acceleration signals at the installation position and send the signals to the signal collector 3 in a wireless communication mode;
the signal combiner 3 estimates the useful life of the contact wire 6 and the catenary 4 using the Miner linear damage accumulation theory.
Further, the contact line 6 and catenary 4 line fatigue stress δ is calculated by the following formula:
wherein:
dynamic lifting force of P-contact line
Modulus of elasticity for E-contact line
Moment of inertia of I-contact line
Measured tension of T-contact line
Z-contact line bending modulus
V-contact line current taking speed
C-contact line wave velocity
Dynamic lifting force P ═ azM, m is the mass of the vibration measuring system 2, azThe vertical vibration acceleration measured by the vibration measuring system 2.
Further, the dynamic displacement in each direction is respectively calculated through the vibration acceleration in three directions measured by the vibration measurement system, and an alarm is given according to a preset threshold value.
The invention has the beneficial effects that: by utilizing a plurality of distributed online independent tension measuring systems, vibration measuring systems and signal collectors, the problems of low efficiency, poor accuracy and slow response speed of the conventional manual inspection detection during the measurement of the working state and parameters of the railway contact network are solved, and the problems that the dynamic parameters of the contact line 6 and the catenary 4 in the contact network cannot be detected in real time and the fatigue damage of the contact line 6 and the catenary 4 cannot be accurately evaluated when an electric locomotive runs by using a special rail car can also be solved.
Drawings
FIG. 1 is a schematic diagram of the composition layout of the present invention.
Detailed Description
The following further describes the embodiments of the present invention with reference to the drawings.
Referring to fig. 1, a dynamic monitoring device for a high-speed railway contact network comprises a tension measuring system 1, a vibration measuring system 2 and a signal collector 3, wherein a set of tension measuring system 1 is respectively installed on a contact wire 6 at two ends of an anchor section of the high-speed railway contact network, a cable compensation rope of a catenary 4 and a span catenary 4, a set of vibration measuring system 2 is respectively installed on the span catenary 4 and at the bottom of a hanger 5 newly installed between the contact wire 6 and the catenary 4, the installation positions of the tension measuring system 1 and the vibration measuring system 2 between each anchor section are shown in fig. 1, the tension measuring system 1 comprises a tension sensor, a signal collector, a power supply and a shell, and the tension measuring system 1 adopts a three-point bending method of a side-pressure type tension sensor to measure the tension.
The side pressure type tension sensor is of a shear beam structure. The cable passes through U type bolt fastening on the sensor, and when the cable received the pulling force, the power was used for the sensor through the leading wheel effect on, and the sensor signal is transmitted to signal collector 3 through signal collector with wireless communication mode after handling.
The vibration measurement system 2 comprises an inertial sensor, a signal collector, a power supply and a shell, wherein the inertial sensor adopts a three-axis accelerometer, when the contact net generates vibration, the inertial sensor detects three axial acceleration signals at a detection point in real time, and when the sampling interval of the accelerometer is t0The uniaxial acceleration data in the period are respectively a1、a2、……、anDuring the period, the cable is displaced in one direction SnCan be expressed as:
the acceleration signal can determine the vibration amplitude of the cable and the frequency of the amplitude range in the vibration period through the analysis and calculation of the signal collector, and the calculation result is transmitted to the signal collector 3 through the signal collector in a wireless communication mode.
The working steps of the whole device are as follows:
the method comprises the following steps: the tension measuring system 1 collects dynamic tension signals of the installation position and transmits the dynamic tension signals to the signal collector 3 in a wireless mode; the vibration measurement system 2 collects three axial dynamic acceleration signals of the installation position and transmits the signals to the signal collector 3 in a wireless communication mode;
step two: the signal collector 3 receives signals from the tension measuring system 1 and the vibration measuring system 2 in a wireless communication mode, stores the signals of the tension measuring system 1 and the vibration measuring system 2, analyzes and calculates the signals, and calculates the dynamic displacement of the vibration measuring system 2 in the up-down (Z-axis) direction, the left-right (Y-axis) direction of the railway track and the three directions of the railway track (X-axis) direction as follows: when the sampling interval of the accelerometer is t0Acceleration data in the up-down (Z-axis) direction in the period are respectively aZ1、aZ2、……、aZnWhile, the displacement S of the upper and lower (Z-axis) in the periodZnExpressed as:
acceleration data in the left and right (Y-axis) directions in the period are respectively aY1、aY2、……、aYnWhile, the displacement S in the left and right (Y-axis) directions in the periodYnExpressed as:
the acceleration data in the direction of the railway track (X axis) in the period are respectively aX1、aX2、……、aXnWhile, the displacement S of the upper and lower (X-axis) in the periodXnExpressed as:
calculating the dynamic lifting force P through the acceleration values in the up-down (Z-axis) direction:
P＝az.m
where m is the mass of the vibration measuring system 2.
When software of the signal collector 3 finds that the detection data of the tension measuring system 1 exceeds the allowable tension range or the detection displacement data and the dynamic lifting force of the vibration measuring system 2 exceed the specified allowable range, the signal collector 3 uploads the excessive tension and displacement, the dynamic lifting force parameter and the position information of the excessive value to a remote control center in time in a wireless communication mode.
Step three: the signal collector 3 classifies and counts the daily dynamic tension signals of each tension measuring system 1, the three axial dynamic displacement signals of each vibration measuring system 2 and the lifting force, and evaluates the service lives of the contact line 6 and the carrier cable 4:
1. the tension (T) of the contact line 6 and the carrier cable 4 is counted and converted into fatigue stress
δ：
Dynamic lifting force of P-contact line
Modulus of elasticity for E-contact line
Moment of inertia of I-contact line
Measured tension of T-contact line
Z-contact line bending modulus
V-contact line current taking speed
C-contact line wave velocity
Dynamic lifting force P ═ azM, m is the mass of the vibration measuring system 2, azThe vertical vibration acceleration measured by the vibration measuring system 2.
2. Estimating the service life by using a Miner linear damage accumulation theory;
determining the working cycle stress sa and the average stress sm by using the fatigue stress delta:
at stress level SiUnder the action of niInjury of the subcirculation is Di＝ni/Ni. If at k stress levels SiUnder the action of each element subjected to niThe minor cycle can define the total damage as
The criterion of destruction is
D＝Σni/Ni＝1
Wherein,
niis at SiNumber of cycles under action, NiIs at SiLife cycle to failure under action
Converting the vibration frequency caused by the driving density and strong wind of b times per day into a time unit (year): t ═ 1/D)/(b ×) 365.
Claims (3)
1. The utility model provides a railway contact net dynamic monitoring device which characterized in that: the device comprises a tension measuring system (1), a vibration measuring system (2) and a signal collector (3), wherein a set of tension measuring system (1) is respectively arranged on a contact line (6) at two ends of an anchor section of a railway contact network, a cable compensating rope of a catenary cable (4) and the catenary cable (4) in a span interval, and a set of vibration measuring system (2) is respectively arranged on the catenary cable (4) in the span interval and at the bottom of a hanger (5) of the contact line (6);
the tension measuring system (1) and the vibration measuring system (2) respectively collect dynamic tension signals and three axial dynamic acceleration signals of the installation position, and send the dynamic tension signals and the three axial dynamic acceleration signals to the signal collector (3) in a wireless communication mode;
the signal collector (3) estimates the practical service life of the contact wire (6) and the carrier cable (4) by utilizing the Miner linear damage accumulation theory.
2. The dynamic monitoring device for the railway contact network of claim 1, which is characterized in that: calculating the contact line (6) and carrier cable (4) line fatigue stress delta by the following formula:
<mrow> <mi>&sigma;</mi> <mo>&ap;</mo> <mfrac> <mi>P</mi> <mi>Z</mi> </mfrac> <mo>&CenterDot;</mo> <msqrt> <mfrac> <mrow> <mi>E</mi> <mi>I</mi> </mrow> <mi>T</mi> </mfrac> </msqrt> <mo>&CenterDot;</mo> <mfrac> <mn>1</mn> <msqrt> <mrow> <mn>1</mn> <mo>-</mo> <msup> <mrow> <mo>(</mo> <mrow> <mi>v</mi> <mo>/</mo> <mi>C</mi> </mrow> <mo>)</mo> </mrow> <mn>2</mn> </msup> </mrow> </msqrt> </mfrac> </mrow>
wherein:
dynamic lifting force of P-contact line
Modulus of elasticity for E-contact line
Moment of inertia of I-contact line
Measured tension of T-contact line
Z-contact line bending modulus
V-contact line current taking speed
C-contact line wave velocity
Dynamic lifting force P ═ azM, m is the mass of the vibration measuring system (2), azThe vibration acceleration in the up-down direction measured by the vibration measuring system (2).
3. The dynamic monitoring device for the railway contact network of claim 1, which is characterized in that: and respectively calculating the dynamic displacement in each direction through the vibration acceleration in three directions measured by the vibration measurement system, and giving an alarm according to a preset threshold value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201610594244.6A CN107655513A (en) | 2016-07-26 | 2016-07-26 | A kind of railway contact line dynamic monitor |
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| CN201610594244.6A CN107655513A (en) | 2016-07-26 | 2016-07-26 | A kind of railway contact line dynamic monitor |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108279104A (en) * | 2018-02-11 | 2018-07-13 | 任兴堂 | Dropper vibration fatigue machine |
| CN110617878A (en) * | 2019-10-31 | 2019-12-27 | 南京林业大学 | Railway contact net vibration frequency detection device |
| CN111721324A (en) * | 2020-05-15 | 2020-09-29 | 中铁第一勘察设计院集团有限公司 | Contact net dropper breakage detection method based on acceleration signals |
| CN113320445A (en) * | 2020-02-28 | 2021-08-31 | 中铁二院工程集团有限责任公司 | Online monitoring and intelligent hidden danger and fault distinguishing and early warning system for contact network |
| CN114049559A (en) * | 2021-11-17 | 2022-02-15 | 西南交通大学 | Non-contact measurement method and device for overall dropper load of railway contact network |
| CN118209240A (en) * | 2024-05-22 | 2024-06-18 | 中国铁建电气化局集团第五工程有限公司 | Contact line tension monitoring method, system, device and storage medium |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108279104A (en) * | 2018-02-11 | 2018-07-13 | 任兴堂 | Dropper vibration fatigue machine |
| CN108279104B (en) * | 2018-02-11 | 2023-05-02 | 任兴堂 | Vibration fatigue testing machine for integral hanger |
| CN110617878A (en) * | 2019-10-31 | 2019-12-27 | 南京林业大学 | Railway contact net vibration frequency detection device |
| CN110617878B (en) * | 2019-10-31 | 2024-04-19 | 南京林业大学 | Railway contact net vibration frequency detection device |
| CN113320445A (en) * | 2020-02-28 | 2021-08-31 | 中铁二院工程集团有限责任公司 | Online monitoring and intelligent hidden danger and fault distinguishing and early warning system for contact network |
| CN111721324A (en) * | 2020-05-15 | 2020-09-29 | 中铁第一勘察设计院集团有限公司 | Contact net dropper breakage detection method based on acceleration signals |
| CN111721324B (en) * | 2020-05-15 | 2021-12-07 | 中铁第一勘察设计院集团有限公司 | Contact net dropper breakage detection method based on acceleration signals |
| CN114049559A (en) * | 2021-11-17 | 2022-02-15 | 西南交通大学 | Non-contact measurement method and device for overall dropper load of railway contact network |
| CN114049559B (en) * | 2021-11-17 | 2022-10-14 | 西南交通大学 | Non-contact measurement method and device for overall dropper load of railway contact network |
| CN118209240A (en) * | 2024-05-22 | 2024-06-18 | 中国铁建电气化局集团第五工程有限公司 | Contact line tension monitoring method, system, device and storage medium |
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