CN108020345A - A kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect - Google Patents
A kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect Download PDFInfo
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- CN108020345A CN108020345A CN201810077167.6A CN201810077167A CN108020345A CN 108020345 A CN108020345 A CN 108020345A CN 201810077167 A CN201810077167 A CN 201810077167A CN 108020345 A CN108020345 A CN 108020345A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
- G01K11/3206—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres at discrete locations in the fibre, e.g. using Bragg scattering
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Abstract
The invention discloses a kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect, comprising：Laser, the Polarization Controller and drive circuit being connected respectively with laser；Wavelength division multiplexer, signal detection device, signal acquisition and control circuit and processor.Wavelength division multiplexer is connected with Polarization Controller and signal detection device respectively, it is also connected with reference to single mode optical fiber and temperature-measuring optical fiber respectively.Signal acquisition and control circuit are connected with signal detection device, drive circuit with processor respectively.The present invention has by using Raman scattering principle, and optical fiber, which disturbs inclined control technology and noise filtering technique, is reducing cost, the advantages of realizing the temperature monitoring to single mode optical fiber in the case of improving monitoring accuracy.
Description
Technical field
The present invention relates to Fiber Optic Pyrometer field, the Single mode communication more particularly to a kind of field suitable for power circuit
The distributed fiber temperature measuring device of Effect of Optical Fiber Raman Scatter.
Background technology
Electric power communication optical cable is the neutral net that intelligent grid " four is distant " automatically controls.Once by exterior abnormal warm on the way
Degree even fire destroys, and consequence is extremely serious.Fibre optic temperature sensor is the new technology in thermometry, and is applied in industry
One of most sensor.The appearance of distributed optical fiber temperature sensor, substantially reduces the cost of acquisition unit information amount, this
One revolution is undoubtedly to the temperature sensor based on electric signal and point type fiber-optical grating temperature sensor.Distribution type fiber-optic
Temperature sensor technology, is exactly moved towards the thermo parameters method situation of tens kilometers of continuous spaces along optical fiber using optical fiber measurement, is strong
The temperature field measurement of the adverse circumstances such as electromagnetic field, high-voltage great-current, inflammable and explosive, complex geometry space and control, there is provided can
Capable new tool.Therefore, for distributed optical fiber temperature sensor to receive extensive attention the characteristics of its own, research is distributed
Fiber temperature sensing system has important theory significance and application value.Optical fiber distributed temperature monitors（DTS,
Distributed Temperature Sensing）, distributed optical fiber temperature measurement is also referred to as, according to optical time domain reflection（OTDR）It is former
Reason, Raman（Raman）Scattering effect and Brillouin scattering effect use the sensitive of temperature so as to fulfill temperature monitoring, total system
Carrier of the optical fiber as sensitive information sensing and signal transmission, has continuous temperature measurement, distributed temperature measuring, real time temperature measurement, anti-electromagnetism
The features such as interference, intrinsic safety, remote monitoring, high sensitivity, simple installation, long-life, be widely used in pipeline, tunnel, electricity
The industries such as cable, petroleum and petrochemical industry, colliery.
In the prior art, the Raman scattering effect principle based on multimode fibre, or the cloth based on single mode optical fiber are usually utilized
In deep scattering principle, distributed optical fiber temperature measurement is carried out to transmission line of electricity, is squeezed into by the laser for producing laser pulse generator
Into optical fiber, its back wave, such as Raman scattering ripple are detected, the amplitude size of the Raman scattering wave reflection is exactly the temperature spot
Temperature height, the speed of reflection interval is exactly distance of this temperature spot to detection device；But since power communication optical cable is basic
Formed for single mode optical fiber.Single mode optical fiber is superfine with fibre core, and numerical aperture is minimum, and transmission mode is single, therefore can not directly answer
With the multimode fibre Raman scattering thermometry with low-cost advantage.If single mode optical fiber is carried out by Brillouin scattering principle
During thermometric, its signal reflected also with stress signal, then needs to carry out the reflected signal not only with temperature signal
Signal demodulation process, removes stress signal, and detection process is complicated, the problem of causing testing cost high.
The content of the invention
The object of the present invention is to provide a kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect, leads to
Cross in the temperature measuring equipment of the single mode optical fiber access present invention in the power communication optical cable having had using Utilities Electric Co., realize
Need not other independent laying detection multimode fibre, realize to above-mentioned communication cable whole section of environment temperature on the way and fire into
The purpose that row is monitored on-line in real time.
In order to realize the above object the present invention is achieved through the following technical solutions：
A kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect, comprising：Laser, swashs with described respectively
The Polarization Controller and drive circuit of light device connection；Wavelength division multiplexer, signal detection device, signal acquisition and control circuit and
Processor.The wavelength division multiplexer is connected with the Polarization Controller and signal detection device respectively, and single with reference respectively
Mode fiber is connected with temperature-measuring optical fiber.The signal acquisition and control circuit respectively with the signal detection device, drive circuit
Connected with processor.The pulsed laser signal that the laser is sent is to the Polarization Controller, while to the drive circuit
Send synchronous triggering signal.The Polarization Controller receives the pulse signal laser of the laser output, and to the pulse
Signal laser carry out depolarization control, produce lose polarization characteristic pulse signal laser and by its through the wavelength division multiplexer to
It is described to be sent with reference to single mode optical fiber and temperature-measuring optical fiber.The drive circuit receive the synchronous triggering signal and according to the signal to
The signal acquisition and control circuit send the instruction of collection signal, and the signal acquisition and control circuit perform.The wavelength-division
Multiplexer gathers the pulse signal laser for losing polarization characteristic and is produced with reference to single mode optical fiber and in temperature-measuring optical fiber respectively
Backward Raman scattering signal and to the signal detection device send.The signal detection device is by the backward Raman
Scattered signal is amplified and is sent to the signal collecting and controlling circuit, and the signal collecting and controlling circuit is processed to
Change into digital signal and sent to the processor, the processor draws thermometric using Raman scattering optical time domain reflection technology
Temperature Distribution along optical fiber.
Preferably, the temperature measuring equipment is additionally provided with host, described to be arranged on reference to single mode optical fiber coiling inside the host；
The processor is arranged on inside the host.
Preferably, the temperature-measuring optical fiber is to be used as sensor by the use of any one optical fiber in communication optical fiber.
Preferably, it is Stokes optical signal and anti-Stokes optical signal that the backward Raman scattering signal, which includes, its
Described in Stokes optical signal it is temperature independent, the anti-Stokes optical signal is then modulated be subject to optical fiber local temperature.
Preferably, the processor is used to perform following computer program steps：Step S1.1, respectively to reference to single mode
Stokes the and Anti-Stokes signals of optical fiber carry out integral mean computing.
Step S1.2, while step S1.1 is performed, also respectively to the Stokes and Anti- with reference to single mode optical fiber
Stokes signals carry out integral mean computing.
Step S2.1, calculus of differences is carried out to Stokes the and Anti-Stokes optical signals after step S1.1 processing to obtain
To the temperature T0 with reference to single mode optical fiber.
Step S2.2, while step S2.1 is performed, to the Stokes and Anti- after step S1.2 processing
Stokes optical signals carry out calculus of differences and obtain detection temperature T1.
Step S3, whole section of temperature T of temperature-measuring optical fiber is calculated according to the temperature T0 with reference to single mode optical fiber and detection temperature T1,
Export the temperature-distance Curve.
Step S4, whole section of the temperature-measuring optical fiber closest to true temperature value is obtained into line noise filter processing to temperature curve
Temperature T.
Step S5, according to default alarm algorithm and/or preset alarm threshold value, whole section of temperature-measuring optical fiber obtained above is judged
Whether temperature T meets above-mentioned alert if, to determine whether to alarm.
The present invention has the following advantages compared with prior art：
The present invention is compared with the prior art is to the thermometric of multimode fibre, the communication light of the invention having had by using Utilities Electric Co.
In the temperature measuring equipment of the single mode optical fiber access present invention in cable, it is real to be implemented without in addition independent laying detection multimode fibre
Now the whole section of environment temperature distribution on the way of the communication optical fiber that has laid and fire are monitored on-line in real time.This hair
Bright by using Raman scattering principle, optical fiber, which disturbs inclined control technology and noise filtering technique, is reducing cost, improves monitoring essence
The temperature monitoring to single mode optical fiber is realized in the case of degree.
Brief description of the drawings
Fig. 1 is a kind of main composition structure of the distributed fiber temperature measuring device of single mode optical fiber Raman scattering effect of the present invention
Block diagram；
Fig. 2 is the meter performed by a kind of processor of the distributed fiber temperature measuring device of single mode optical fiber Raman scattering effect of the present invention
Calculate procedure flow chart.
Embodiment
Below in conjunction with attached drawing, by describing a preferable specific embodiment in detail, the present invention is further elaborated.
As shown in Figure 1, a kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect of the present invention, bag
Contain：Laser, the Polarization Controller being connected respectively with the laser, drive circuit, wavelength division multiplexer, its respectively with it is described partially
Shake controller, signal detection device, connected with temperature-measuring optical fiber with reference to single mode optical fiber；The temperature-measuring optical fiber is to utilize communication optical fiber
In any one optical fiber as sensor, the temperature branch information of detection sensor.Host equipped with processor, it is described with reference to single
Mode fiber coiling is arranged on inside the host.Signal acquisition and control circuit, it with the signal detection device, drives respectively
Dynamic circuit is connected with processor.
The laser is used to be generated and transmitted by pulse signal laser, and the Polarization Controller is used to receive the laser
The pulse signal laser of output, and depolarization control is carried out to the pulse signal laser, produce the pulse for losing polarization characteristic
Signal laser；By the pulse signal laser for losing polarization characteristic through the wavelength division multiplexer to it is described with reference to single mode optical fiber and
Temperature-measuring optical fiber is sent.Meanwhile the laser also to the drive circuit convey synchronous triggering signal, the drive circuit according to
The synchronous triggering signal received sends the instruction of collection signal to the signal acquisition and control circuit, the signal acquisition and
Control circuit performs.Lost described in the wavelength division multiplexer collection pulse signal laser of polarization characteristic with reference to single mode optical fiber and
The backward Raman scattering signal that is produced in temperature-measuring optical fiber is simultaneously sent to the signal detection device；The backward Raman scattering
It is stokes light that signal, which includes,（Stoks）Signal and anti-Stokes（Anti-Stoks）Optical signal, wherein stokes light
It is almost temperature independent, and anti-Stokes light is then modulated be subject to optical fiber local temperature.
The backward Raman scattering signal is amplified and to the signal acquisition and control by the signal detection device
Circuit processed is sent, and the signal collecting and controlling circuit is processed to change into digital signal and is sent to the processor, institute
State processor and Temperature Distribution along temperature-measuring optical fiber is drawn using Raman scattering optical time domain reflection technology.
As shown in Fig. 2, the processor is used to perform following computer program steps：Step S1.1, respectively to reference
Stokes the and Anti-Stokes signals of single mode optical fiber carry out integral mean computing.
Step S1.2, while step S1.1 is performed, also respectively to the Stokes and Anti- with reference to single mode optical fiber
Stokes signals carry out integral mean computing.
Step S2.1, calculus of differences is carried out to Stokes the and Anti-Stokes optical signals after step S1.1 processing to obtain
To the temperature T with reference to single mode optical fiber0。
Step S2.2, while step S2.1 is performed, to the Stokes and Anti- after step S1.2 processing
Stokes optical signals carry out calculus of differences and obtain detection temperature T1。
Step S3, according to the temperature T with reference to single mode optical fiber0With detection temperature T1Whole section of temperature T of temperature-measuring optical fiber is calculated,
Export the temperature-distance Curve.
Step S4, whole section of the temperature-measuring optical fiber closest to true temperature value is obtained into line noise filter processing to temperature curve
Temperature T.
Step S5, according to default alarm algorithm and/or preset alarm threshold value, whole section of temperature-measuring optical fiber obtained above is judged
Whether temperature T meets above-mentioned alert if, to determine whether to alarm.
The operation principle of the Polarization Controller is：Due to the polarization correlated influence in signals transmission, light
Change causes serious polarization correlated noise to polarization state at random, optical fiber disturb inclined technology be by by the polarised light of scrambler, with compared with
High speed constantly changes its polarization state, so that it is special to make general effect of the polarised light in certain period of time lose polarization
Property.
Noise filtering in the step S4 handles reason：Since optical signal is very small, and light is in transmitting procedure,
Phase and polarization state are all changed, and generate various noises, and useful signal has substantially been flooded by noise, it is necessary to for letter
Number it is special, analyse in depth useful signal the characteristics of, design corresponding wave filter, noise filtering fallen, retain useful signal.
Although present disclosure is discussed in detail by above preferred embodiment, but it should be appreciated that above-mentioned
Description is not considered as limitation of the present invention.After those skilled in the art have read the above, for the present invention's
A variety of modifications and substitutions all will be apparent.Therefore, protection scope of the present invention should be limited to the appended claims.
Claims (5)
1. a kind of distributed fiber temperature measuring device based on single mode optical fiber Raman scattering effect, it is characterised in that include：
Laser, the Polarization Controller and drive circuit being connected respectively with the laser；Wavelength division multiplexer, signal detection
Device, signal acquisition and control circuit and processor；
The wavelength division multiplexer is connected with the Polarization Controller and signal detection device respectively, and it is also single with reference respectively
Mode fiber is connected with temperature-measuring optical fiber；
The signal acquisition and control circuit are connected with the signal detection device, drive circuit with processor respectively；
The pulsed laser signal that the laser is sent sends synchronous touch to the Polarization Controller, while to the drive circuit
Signal；
The Polarization Controller receives the pulse signal laser of the laser output, and the pulse signal laser is solved
Polarization Control, produces the pulse signal laser for losing polarization characteristic and it is referred to single-mode optics to described through the wavelength division multiplexer
Fine and temperature-measuring optical fiber is sent；
The drive circuit receives the synchronous triggering signal and is sent according to the signal to the signal acquisition and control circuit
The instruction of signal is gathered, the signal acquisition and control circuit perform；
The wavelength division multiplexer gathers the pulse signal laser for losing polarization characteristic in reference single mode optical fiber and is surveying respectively
The backward Raman scattering signal that is produced in warm optical fiber is simultaneously sent to the signal detection device；
The signal detection device by the backward Raman scattering signal be amplified and to the signal collecting and controlling electricity
Road is sent, and the signal collecting and controlling circuit is processed to change into digital signal and is sent to the processor, the place
Reason device draws the Temperature Distribution along temperature-measuring optical fiber using Raman scattering optical time domain reflection technology.
2. the distributed fiber temperature measuring device as claimed in claim 1 based on single mode optical fiber Raman scattering effect, its feature exist
In the temperature measuring equipment is additionally provided with host, described to be arranged on reference to single mode optical fiber coiling inside the host；The processor is set
Put inside the host.
3. the distributed fiber temperature measuring device of single mode optical fiber Raman scattering effect as claimed in claim 1, it is characterised in that institute
It is to be used as sensor by the use of any one single mode optical fiber in communication cable to state temperature-measuring optical fiber.
4. the distributed fiber temperature measuring device as claimed in claim 1 based on single mode optical fiber Raman scattering effect, its feature exist
In it is Stokes optical signal and anti-Stokes optical signal that the backward Raman scattering signal, which includes, wherein the stoke
This optical signal is temperature independent, and the anti-Stokes optical signal is then modulated be subject to optical fiber local temperature.
5. the distributed fiber temperature measuring device as claimed in claim 1 or 2 based on single mode optical fiber Raman scattering effect, its feature
It is, the processor is used to perform following computer program steps：Step S1.1, respectively to reference to single mode optical fiber
Stokes and Anti-Stokes signals carry out integral mean computing；
Step S1.2, while step S1.1 is performed, also respectively to the Stokes and Anti-Stokes with reference to single mode optical fiber
Signal carries out integral mean computing；
Step S2.1, calculus of differences is carried out to Stokes the and Anti-Stokes optical signals after step S1.1 processing to be joined
Examine the temperature T of single mode optical fiber0；
Step S2.2, while step S2.1 is performed, to Stokes the and Anti-Stokes light after step S1.2 processing
Signal carries out calculus of differences and obtains detection temperature T1；
Step S3, according to the temperature T with reference to single mode optical fiber0With detection temperature T1Whole section of temperature T of temperature-measuring optical fiber is calculated, exports
Temperature-the distance Curve；
Step S4, whole section of temperature of temperature-measuring optical fiber closest to true temperature value is obtained into line noise filter processing to temperature curve
T；
Step S5, according to default alarm algorithm and/or preset alarm threshold value, whole section of temperature of temperature-measuring optical fiber obtained above is judged
Whether T meets above-mentioned alert if, to determine whether to alarm.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110031124A (en) * | 2019-02-27 | 2019-07-19 | 上海拜安传感技术有限公司 | A kind of distribution single mode optical fiber extra long distance Raman temperature transducer |
| CN113819401A (en) * | 2021-11-17 | 2021-12-21 | 西南石油大学 | Desert buried pipeline monitoring system and method based on optical fiber vibration and temperature test |
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| US20130100984A1 (en) * | 2011-10-24 | 2013-04-25 | Yokogawa Electric Corporation | Opticalfiber temperature distribution measurement apparatus |
| CN204043818U (en) * | 2014-07-16 | 2014-12-24 | 金海新源电气江苏有限公司 | Distributed optical fiber temperature sensor |
| CN104596670A (en) * | 2015-02-05 | 2015-05-06 | 吉林大学 | Method for solving temperature drift of distributed optical fiber Raman temperature sensing system |
| CN105136337A (en) * | 2015-05-28 | 2015-12-09 | 华中科技大学 | Raman distributed temperature measurement system based on mode multiplexing and temperature measurement method |
| CN104101447B (en) * | 2014-07-16 | 2017-01-18 | 金海新源电气江苏有限公司 | Distributed optical fiber temperature sensor and method for removing nonlinear error of same |
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Patent Citations (6)
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| US8152370B2 (en) * | 2007-07-31 | 2012-04-10 | Politecnico Di Milano | Sensor and method for determining temperature along an optical fibre |
| US20130100984A1 (en) * | 2011-10-24 | 2013-04-25 | Yokogawa Electric Corporation | Opticalfiber temperature distribution measurement apparatus |
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| CN104101447B (en) * | 2014-07-16 | 2017-01-18 | 金海新源电气江苏有限公司 | Distributed optical fiber temperature sensor and method for removing nonlinear error of same |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110031124A (en) * | 2019-02-27 | 2019-07-19 | 上海拜安传感技术有限公司 | A kind of distribution single mode optical fiber extra long distance Raman temperature transducer |
| CN113819401A (en) * | 2021-11-17 | 2021-12-21 | 西南石油大学 | Desert buried pipeline monitoring system and method based on optical fiber vibration and temperature test |
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Application publication date: 20180511 |