CN101863278A - High-speed railway axle-counting device based on optical grating reflection spectrum widening - Google Patents
High-speed railway axle-counting device based on optical grating reflection spectrum widening Download PDFInfo
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- CN101863278A CN101863278A CN 201010191152 CN201010191152A CN101863278A CN 101863278 A CN101863278 A CN 101863278A CN 201010191152 CN201010191152 CN 201010191152 CN 201010191152 A CN201010191152 A CN 201010191152A CN 101863278 A CN101863278 A CN 101863278A
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Abstract
The invention discloses a high-speed railway axle-counting device based on optical grating reflection spectrum widening, which has the working principle that a light beam sent out by a broad band light source enters into a fiber grating sensor stuck at the bottom of a rail through an optical circulator; the reflected light of fiber grating enters into a photoelectric detector through the optical circulator and then is converted into an electrical signal; digital-to-analogue conversion is carried out on the electrical signal by an ADC after the signal is amplified and filtered; and an axle-counting detector is used for shaping a digital signal, and axle-counting pulse can be obtained. The high-speed railway axle-counting device solves the problems of poor electromagnetic compatibility, short analog signal transmission distance and the like of the existing railway axle-counting device; and compared with the similar device adopting grating center wavelength demodulation, the high-speed railway axle-counting device is not interfered by ambient temperature and does not need temperature compensation measure.
Description
Technical field
The present invention relates to realize the technology of train meter axle at the optical fiber grating reflectance spectra broadening effect that field of track traffic utilizes rail strain uneven distribution to cause.
Background technology
Axle-counting device claims wheel counting apparatus again, in order to detect the axletree number of train by certain a bit (axle-counting points) on the railway, checking between two axle-counting points or the space situation in the track section, or judge the time of train, from the equipment of dynamic correction train driving mileage etc. by axle-counting points.The sixties in 19th century, Germany begins to explore a mode of using tricks and detects the technology of train occupation track section, but up to mid-term the 1950's, the track axle count device just formally uses in the Germany.After this, Europe, Vietnam, TaiWan, China uses wheel counting apparatus, and the inland of China railway uses track circuit and responser traditionally, is also using wheel counting apparatus to replace track circuit on the part existing line at present.Wheel counting apparatus partly is made up of sensor, count comparator etc.When the informational needs long-distance transmissions of the vehicle number of axle, wheel counting apparatus also need adopt transmission equipment (Wang Gengsheng, " a kind of development of novel intelligent type axle count sensor ", sensor and instrument and meter, 2009 the 25th the 1st phases of volume).
The early stage sensor that uses generally is a mechanical type, the general at present electromagnetic type that adopts.Electromagnetic senser is made up of magnetic head, transmitter, receptor three parts.Magnetic head has one to send the both sides that coil and receiving coil are contained in rail respectively.Transmitter is presented the electric current of upper frequency to the transmission coil of magnetic head, produces alternating magnetic field around making it, and by the receiving coil of different medium loop chains such as air, rail, fastener to magnetic head, induces alternating-current voltage/AC voltage.When axletree passed through magnetic head, the shielding action of wheel and the diffusion of wheel rim made loop chain change to the magnetic flow of the receiving coil of magnetic head, and induced voltage are significantly reduced.Receptor converts the induced voltage of this variation to the axletree electric impulse signal.Count comparator mainly is made up of counting machine, discriminator, comparator.
The electromagnetic path sensor (wheel sensor) that existing axle-counting device generally adopts causes Sensor section that electromagnetic compatibility is had relatively high expectations, and is subject to conductor and disturbs (single shaft dolly, pedestrian on the track) and produce "+-1 " phenomenon.The rail portion of sensor and high-frequency signal sending and receiving end are limited by signal transmission distance; generally in 10 meters; cause repacking to survey box (high frequency E AK) and must be placed in outdoor track place near axle-counting points; thereby in power supply; lightning protection; aspects such as maintenance cause inconvenience, need independent APS power supply, high-level lightning protection.The information that obtains from sensor sends it back an indoor main frame in the mode of FSK by the four-core transmission cable behind first treatment, have on the line and need carry out lightning protection.In a word, using the electromagnetic path sensor to cause need be to carrying out strict lightning protection in the front-end processing of system and the signal transmission, the electromagnetism capacitor design, and independent power supply, maintenance are also inconvenient.
Electromagnetic braking is used in (maximum speed is greater than 160km/h) on the high speed train.There is the very big sheetmetal of some volumes to be installed on the bogie truck of vehicle, on several centimetres of rail.They are detected mistakenly by axle-counting device sometimes, and think other axletree.One side of track may only take place in this, because the bending of magnetic domain, defective of track geometry size or the like causes signal system chaotic even need the memory of reset detection.
In order to overcome the shortcoming of electromagnetic sensor (wheel sensor), the axle-counting device that adopts the electronics strain sensor to catch the strain disturbance that produces when train crosses on rail and then obtain counting a pulse is proved to be and can overcomes the shortcoming that the axle-counting device that adopts the electromagnetic path sensor is subject to disturb, and can be to the measurement of train wheel load.
Fiber-optic grating sensor has obtained paying attention to widely at sensory field, and optical fiber grating has several outstanding major advantages: 1) the light frequency order of magnitude is THz, and its frequency band range is very wide, and dynamic range is very big, is not subjected to the disturbance of electromagnetic field; 2) signal adopts Wavelength-encoding, is not subjected to the influence of factors such as the fluctuating of the intensity of light source, random fluctuation that fiber microbending loss causes and coupling loss, and is insensitive to ambient interference; 3) material of optical fiber grating is a silicon dioxide, has stronger corrosion resistance; 4) self calibration and be easy to integrated a plurality of sensor multiplexings in same optical fiber; Core diameter is thin and pliable and tough, is easy to lay; 5) be easy to realize the large tracts of land distributed measurement.Use fiber-optic grating sensor to replace the electronics strain sensor can improve sensitivity greatly, the adaptive capacity of harsh environment is also improved greatly strain, can both normal operation when ice, rain, snow and wet weather.Traditional fiber-optic grating sensor is measured external strain by detection optical fiber grating foveal reflex wavelength change.Temperature-strain cross sensitivity phenomenon foveal reflex wavelength that optical fiber grating exists is subjected to the double influence of temperature, strain.The foveal reflex wave length shift that temperature traverse causes in strain measurement is regarded as a kind of interference, must eliminate temperature disturbance by the temperature compensating measure.This has just increased the structural complexity of optical fiber grating axle-counting device, and the cost of system also increases greatly.Adopt the demodulation mode scanning speed of length scanning limited, can't satisfy catch high speed railway (＞160km/h) in (＞80hz) the requirement of the high speed strain sweep signal that produces of Train Wheel.
Generally, based on the railway axle-counting device of rail strain detecting technology, can eliminate "+-1 " phenomenon of electromagnetism axle-counting device, disturbance rejection.Use the axle-counting device of optical fiber grating all to increase on reliability, sensitivity, electromagnetic compatibility, but the mode of Wavelength demodulation is subject to the interference of temperature fluctuation, demodulation speed is slow, the cost height.Therefore purpose of the present invention is exactly that the technology based on optical fiber grating reflectance spectra broadening is incorporated in the design of axle-counting device, obtains a kind of temperature disturbance that is not subjected to, and is with low cost, is fit to the axle-counting device of high speed railway needs.
Summary of the invention
Content of the present invention provides a kind of axle-counting device of high-speed railway based on optical fiber grating reflectance spectra broadening technology, to overcome the problem that existing axle-counting device is subject to external electromagnetic, temperature disturbance.The objective of the invention is to realize by following means:
Based on the axle-counting device of high-speed railway of optical grating reflection spectrum widening, by wideband light source, optical Fiber Closure, stick on the rail ad-hoc location optical fiber grating, count axis detector and be linked at optical fiber grating and the optical circulator of meter between the axis detector formed; Described meter axis detector comprises photodetector, trans-impedance amplifier, amplifying circuit, low-pass filter circuit, A/D modular converter, arithmetic and logic unit and communication interface.
Mode of operation is counted axle to train: the broad band light beam that is sent by wideband light source (ASE or SLED) is entered the optical fiber grating that sticks on rail ad-hoc location bottom by optical circulator (port one-port 2), light optical grating reflection light enters photodetector by optical circulator (port 2-〉port 3), be converted to amplify behind the electric signal, after the filtering, A/D conversion, the meter axis detector that is made of MCU or DSP is carried out shaping to digital signal and is obtained the pulse of meter axle.
When train wheel crosses the rail of pasting the light grating sensor, can produce the scanning strain in the rail bottom, the axial strain that wherein causes the rail length direction that the optical fiber grating reflectance spectra changes reduces to both sides gradually in wheel track contact point place maximum.By warbling of optical fiber grating sensing theory as can be known, when external temperature or axial strain were uneven distribution in the size of optical fiber grating grid region, in the time of the center wavelength variation of light optical grating reflection spectrum, the bandwidth of reflectance spectra also increased thereupon.Optical fiber grating reflectance spectra bandwidth variable quantity can be approximately linear with grating grid region maximum temperature gradient or strain gradient.When optical fiber grating reflectance spectra broadening, maximum reflectivity descends to some extent, and the reflected light light intensity increases with bandwidth.In actual use, ambient temperature is evenly distributed in the size of grating grid region, and the rail axial strain is not evenly distributed when having train wheel to cross, and causes that when train wheel crosses the rail axial strain is trapezoidal profile, and the reflected light light intensity also increases thereupon.From optical fiber grating intensity of reflected light signal, can obtain information such as number that train crosses wheel, wheel load.
The present invention adopts the intensity demodulation mode based on optical fiber grating reflectance spectra broadening, and light optical grating reflection spectrum must be in the wideband light source luminous power spectrum flat region.The axial strain gradient difference is proportional in light intensity variation maxim and the grid region, and optical fiber grating is laid in appropriate position to guarantee the sensitivity of system.
Description of drawings is as follows:
Fig. 1 is a structural representation of the present invention.
Fig. 2 is a field conduct mode block diagram of the present invention.
Fig. 3 is the composition structured flowchart of meter axis detector of the present invention.
Fig. 4 is an optical fiber grating laying place rail strain distribution diagram of curves of the present invention.
Fig. 5 is an optical fiber grating reflectance spectra spectrogram of the present invention.
Fig. 6 is the light intensity-wheel load graph of relation of the invention process wheel remeasurement.
Fig. 7 is a meter axis detector meter axle operation program diagram of circuit of the present invention.
The specific embodiment
The invention will be further described below in conjunction with accompanying drawing.
Fig. 1 is an exemplary device figure of the invention process, the light beam that wideband light source 101 sends enters the fiber-optic grating sensor 103 that sticks on the rail ad-hoc location through optical circulator (port one-port 2) 102, the reflected light process optical circulator of optical fiber grating (port 2-〉port 3) enter meter axis detector 104, the reflected light light intensity signal is handled obtaining axle information.
The present invention at the embodiment at railway scene as shown in Figure 2.The wide range light beam that is sent by wideband light source 201 enters the optical fiber grating 203 that sticks on the rail bottom through optical Fiber Closure 202, and reflected light enters the meter axis detector 204 that is placed on the indoor equipment chamber.As shown in Figure 3, photodetector 301 in the meter axis detector is converted to the electric current electric signal with the intensity signal that receives, current signal carries out that I-V conversion, amplifying circuit 303 are amplified, becomes digital signal by the A/D modular converter after low-pass filter circuit 304 filtering and give the arithmetic and logic unit 305 that is made of MCU again through trans-impedance amplifier 302, the digital signal shaping is obtained information such as the pulse of meter axle, wheel load.Transfer out by communication interface (forms such as CAN, 485, ethernet) at last.Wherein wideband light source, optical Fiber Closure and meter axis detector are placed on indoorly, and it is outdoor to have only fiber-optic grating sensor to be placed on.
The present invention counts principle such as Fig. 4 that repacking is surveyed, and is shown in Figure 5.Rail is after being subjected to wheel pressure, because two ends are supported by sleeper, rail is equivalent to single supported beam.Below rail, produce tensile stress, produce compression effort up, on the cross section, produce friction stress.Suppose that railway basis, fastener and bed course are rigid body, to the rail condition that imposes restriction, 10 tons of wheel load pressure-loaded positions are at the mid point of span, and load evenly is carried on the center line node, and the axial strain on the center line of rail bottom distributes as shown in Figure 4.For the reflectance spectra broadening amount that makes optical fiber grating is big as much as possible, it is axial strain negative maximum value place among Fig. 4 that grating is sticked on the strain gradient maximum.When optical fiber grating reflectance spectra broadened bandwidth (as Fig. 5), because the wideband light source optical power distribution is that the reflected light light intensity also increases with the reflectance spectra broadening uniformly in reflectance spectra.The light intensity maxim depends on the wheel load that crosses wheel, and its corresponding relation as shown in Figure 6.The present invention can also obtain the wheel load information of train except that train meter axle.
The meter axle program circuit of meter axis detector of the present invention as shown in Figure 7.Whether the start back program at first fore-end of detecting device is working properly, if do not detect light intensity signal or be lower than certain threshold value, then decision maker is occurred by fault, and directly the meter axle is also exported breakdown signal request maintenance.If fore-end is working properly, when light intensity signal increases with itself and a meter axle threshold, as then be judged as greater than threshold value wheel through otherwise for disturbing.And from light intensity signal maximum value, obtain wheel load information.
Compare with existing meter shaft technology, structure of the present invention is very simple, is not subjected to the ambient temperature variable effect to need not temperature-compensating, adopts intensity demodulation speed to be exceedingly fast, the needs of the occasions such as suitable high-speed railway. Extra-heavy is transferred, and typical case of the present invention uses:
(1) free time of monitoring track section or switch section with take situation: because the needs of train dispatching, the train that railway section is travelled need to carry out locking to be followed the tracks of, and has or not train driving in the certain range, to avoid train and comes up with or bump against; Track switch goes out AT STATION, needs perception to have or not train to cross and speed, so that the automatic operation of switch mechanism.
(2) monitoring integrity of train: at train travelling process because the generation that a variety of causes may cause railway car to disconnect, by train fixedly the number of axle and the contrast of surveying the number of axle can monitor the integrality of train, in time dispose.
(3) monitoring train overload, unbalance loading: by can obtaining to cross the wheel load of train to the monitoring of rail strain, and then know train load by inference, thereby detect train overloading free, unbalance loading phenomenon are arranged.
Claims (4)
1. based on the axle-counting device of high-speed railway of optical grating reflection spectrum widening, it is characterized in that: by wideband light source, optical Fiber Closure, stick on the rail ad-hoc location optical fiber grating, count axis detector and be linked at optical fiber grating and the optical circulator of meter between the axis detector formed; Described meter axis detector comprises photodetector, trans-impedance amplifier, amplifying circuit, low-pass filter circuit, A/D modular converter, arithmetic and logic unit and communication interface.
2. the axle-counting device of high-speed railway based on the optical grating reflection spectrum widening as claimed in claim 1 is characterized in that using Gauss to cut the location optical fiber grating as the sensor fibre grating.
3. the axle-counting device of high-speed railway based on the optical grating reflection spectrum widening as claimed in claim 1 is characterized in that described optical fiber grating sticks on the rail bottom axial strain distribution gradient maximum between rail two sleepers or the deck.
4. the axle-counting device of high-speed railway based on the optical grating reflection spectrum widening as claimed in claim 1, signal shaping obtains the pulse of meter axle to the optical fiber grating intensity of reflected light to it is characterized in that counting axis detector.
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| CN 201010191152 CN101863278A (en) | 2010-06-03 | 2010-06-03 | High-speed railway axle-counting device based on optical grating reflection spectrum widening |
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| CN 201010191152 CN101863278A (en) | 2010-06-03 | 2010-06-03 | High-speed railway axle-counting device based on optical grating reflection spectrum widening |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP3069952A1 (en) * | 2015-03-20 | 2016-09-21 | Thales Deutschland GmbH | Axle counting method and axle counting device |
| CN106476845A (en) * | 2016-10-27 | 2017-03-08 | 林和光 | Track axle count fiber-optic grating sensor and track axle count devices, systems and methods |
| CN106494454A (en) * | 2016-10-25 | 2017-03-15 | 中国神华能源股份有限公司 | Railway axis-counting device, method, system and signal handling equipment |
| CN106985879A (en) * | 2017-04-18 | 2017-07-28 | 卡斯柯信号有限公司 | A kind of train occupation detecting system and method |
| CN110091893A (en) * | 2019-04-28 | 2019-08-06 | 北京全路通信信号研究设计院集团有限公司 | A kind of grating meter shaft track circuit system and working method |
| CN110450824A (en) * | 2019-07-26 | 2019-11-15 | 深圳市科安达轨道交通技术有限公司 | A kind of railway signal monitoring system based on multi-channel optical fibre communication |
| CN110497933A (en) * | 2019-08-27 | 2019-11-26 | 武汉理工大学 | Safety-type train axle counting system and method based on dual wavelength |
| CN113879358A (en) * | 2021-10-29 | 2022-01-04 | 国能朔黄铁路发展有限责任公司 | Track state monitoring device and method, control device and storage medium |
| CN114454915A (en) * | 2022-02-25 | 2022-05-10 | 北京全路通信信号研究设计院集团有限公司 | Fiber grating axle counting method and system |
| TWI791497B (en) * | 2017-03-22 | 2023-02-11 | 法商阿爾斯通運輸科技公司 | A safety device for a railway vehicle, a railway vehicle, a method for preserving safety of such a railway vehicle, and associated computer program |
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016150670A1 (en) * | 2015-03-20 | 2016-09-29 | Thales Deutschland Gmbh | Axle counting method and axle counting device |
| EP3069952A1 (en) * | 2015-03-20 | 2016-09-21 | Thales Deutschland GmbH | Axle counting method and axle counting device |
| CN107921978A (en) * | 2015-03-20 | 2018-04-17 | 塔莱斯管理与服务德国有限责任公司 | Axle counting method and axle-counting device |
| AU2016236557B2 (en) * | 2015-03-20 | 2018-06-21 | Thales Management & Services Deutschland Gmbh | Axle counting method and axle counting device |
| US10272930B2 (en) | 2015-03-20 | 2019-04-30 | Thales Deutschland Gmbh | Axle counting method and axle counting device |
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| CN106494454A (en) * | 2016-10-25 | 2017-03-15 | 中国神华能源股份有限公司 | Railway axis-counting device, method, system and signal handling equipment |
| CN106494454B (en) * | 2016-10-25 | 2018-05-29 | 中国神华能源股份有限公司 | Railway axis-counting device, method, system and signal handling equipment |
| CN106476845A (en) * | 2016-10-27 | 2017-03-08 | 林和光 | Track axle count fiber-optic grating sensor and track axle count devices, systems and methods |
| TWI791497B (en) * | 2017-03-22 | 2023-02-11 | 法商阿爾斯通運輸科技公司 | A safety device for a railway vehicle, a railway vehicle, a method for preserving safety of such a railway vehicle, and associated computer program |
| CN106985879A (en) * | 2017-04-18 | 2017-07-28 | 卡斯柯信号有限公司 | A kind of train occupation detecting system and method |
| CN110091893A (en) * | 2019-04-28 | 2019-08-06 | 北京全路通信信号研究设计院集团有限公司 | A kind of grating meter shaft track circuit system and working method |
| CN110450824A (en) * | 2019-07-26 | 2019-11-15 | 深圳市科安达轨道交通技术有限公司 | A kind of railway signal monitoring system based on multi-channel optical fibre communication |
| CN110497933A (en) * | 2019-08-27 | 2019-11-26 | 武汉理工大学 | Safety-type train axle counting system and method based on dual wavelength |
| CN110497933B (en) * | 2019-08-27 | 2021-10-15 | 武汉理工大学 | Dual-wavelength-based safe train axle counting system and method |
| CN113879358A (en) * | 2021-10-29 | 2022-01-04 | 国能朔黄铁路发展有限责任公司 | Track state monitoring device and method, control device and storage medium |
| CN114454915A (en) * | 2022-02-25 | 2022-05-10 | 北京全路通信信号研究设计院集团有限公司 | Fiber grating axle counting method and system |
| CN114454915B (en) * | 2022-02-25 | 2023-10-27 | 北京全路通信信号研究设计院集团有限公司 | Fiber bragg grating shaft counting method and system |
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Application publication date: 20101020 |