CN108760078A - Distributed optical fiber temperature measuring method and system - Google Patents
Distributed optical fiber temperature measuring method and system Download PDFInfo
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- CN108760078A CN108760078A CN201810369953.3A CN201810369953A CN108760078A CN 108760078 A CN108760078 A CN 108760078A CN 201810369953 A CN201810369953 A CN 201810369953A CN 108760078 A CN108760078 A CN 108760078A
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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
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Abstract
This application involves a kind of distributed optical fiber temperature measuring method and system, the method includes：Using two thermometric channels, respectively from the both ends of sensor fibre alternating Injection Signal light into the sensor fibre；The rear orientation light for the signal light that one thermometric channel is injected in the acquisition of one end of the sensor fibre from the end, another described thermometric channel is similarly operated in the other end of the sensor fibre；Collected rear orientation light is handled, temperature demodulation formula is obtained, so as to solve the temperature value of each point on the sensor fibre.The present processes are measured using two thermometric channels, are eliminated the flow for solving two light path temperature decline coefficients, to reduce the complexity of temperature demodulation formula, and can also be reduced measurement error.
Description
Technical field
This application involves technical field of optical fiber sensing, and in particular to a kind of distributed optical fiber temperature measuring method and system.
Background technology
Currently, 3 D stereo storage is a main trend of logistics transportation and storage.For the temperature measurement side of tiered warehouse facility
Case mainly has the point type temperature-sensing system based on sensor network, the video detection scheme based on flame identification, and is based on
The distributed temperature monitoring scheme of optical fiber temperature-measurement.
In recent years, the distributed optical fiber temperature measurement based on Raman scattering (Distributed Temperature Sensing,
DTS) system is furtherd investigate and is developed.Due to the characteristic with electromagnetism interference, measurement distance length, distributed optical fiber temperature measurement exists
Numerous industrial circles are widely used, such as the leak detection of the monitoring of fire alarm, security wire and pipeline road.However,
The measurement result of DTS system can be by optical fiber insertion loss, fiber transmission attenuation (also referred to as optical fiber attenuation) and APD
The influence of (Avalanche Photo Diode, avalanche photodide) dark current noise.
In the related technology, demodulation scheme lays particular emphasis on the influence for reducing dark current noise and optical fiber attenuation, it is therefore desirable to measure
The dark current noise of APD circuits simultaneously removes it, it is also necessary to solve stokes light, the attenuation coefficient of anti-Stokes light disappears
Except the influence of optical fiber attenuation.In the related technology, it is believed that dark current noise tends towards stability after the completion of APD Circuit assemblies, artificially provides
One definite value is as dark current noise value；However, APD circuits work when temperature, bias voltage can all influence output as a result,
So dark current noise shows fluctuation in different measurement periods, dark current noise can be caused into measurement result as definite value
Fluctuate that larger, error is also larger.Further, since cabling scenario and factors, the attenuation coefficient such as fiber ageing may be in different moments
Different Results are presented；The process for thus solving attenuation coefficient is comparatively laborious, so that demodulation scheme is become complicated, and calculation amount is larger.
Invention content
To overcome the problems, such as at least to a certain extent present in the relevant technologies, the application provides a kind of distribution type fiber-optic survey
Warm method and system.
According to the embodiment of the present application in a first aspect, provide a kind of distributed optical fiber temperature measuring method, including：
Using two thermometric channels, respectively from the both ends of sensor fibre alternating Injection Signal light into the sensor fibre；
The back scattering for the signal light that one thermometric channel is injected in the acquisition of one end of the sensor fibre from the end
Light, another described thermometric channel are similarly operated in the other end of the sensor fibre；
Collected rear orientation light is handled, temperature demodulation formula is obtained, so as to solve the sense light
The temperature value of each point on fibre.
Further, this method further includes：
A part is chosen on the sensor fibre is used as temperature-measuring optical fiber section；
At least one reference optical fiber section is chosen in the part that temperature-measuring optical fiber section is not belonging on the sensor fibre, and will be described
Reference optical fiber section is placed under isoperibol.
Further, described that collected rear orientation light is handled, including：
Changed according to the signal value of rear orientation light, isolates the scattering light data for belonging to the temperature-measuring optical fiber section；
According to after separation as a result, thermometric by the same point in the temperature-measuring optical fiber section on two thermometric channels
As a result location matches are carried out.
Further, described that collected rear orientation light is handled, further include：
After carrying out location matches, the scattering light data of the reference optical fiber section is acquired；
The undetermined parameter in the temperature demodulation formula is solved according to measurement result, and undetermined parameter is substituted into the temperature
It demodulates in formula.
Further, the temperature demodulation formula is：
Wherein：
As undetermined parameter, T (l) are temperature funtion related with tested point position, and k is Boltzmann constant, and h is
Planck's constant, ΔvFor the Raman frequency shift amount of sensor fibre.
Further, described to isolate the scattering light data for belonging to the temperature-measuring optical fiber section, including：
Investigate the correspondence that signal value I changes as distance value l increases；
Data with stable linear relationship between selection signal value I and distance value l, as belong to the temperature-measuring optical fiber
The scattering light data of section；
Wherein, I is the signal value of collected rear orientation light, and l is the point and signal acquisition point that the back scattering occurs
The distance between value.
Further, two thermometric channels are realized using a wavelength division multiplexer, and the both ends of the sensor fibre connect
It is connected on the same wavelength division multiplexer.
According to the second aspect of the embodiment of the present application, a kind of temperature-measuring system of distributed fibers, including light-pulse generator, number are provided
According to capture card and computer；Further include two thermometric channels, sensor fibre, two APD circuits and two signal amplifiers；
The light-pulse generator provides signal light to two thermometric channels；The both ends of the sensor fibre respectively with two
The thermometric channel connection, two thermometric channels are respectively from the both ends of sensor fibre alternating into the sensor fibre
Injection Signal light；
Two thermometric channels respectively pass sequentially through respectively from the both ends collection of scattered light signal of the sensor fibre
One APD circuit and a signal amplifier transmit a signal to the data collecting card；The data collecting card
It is connect with the computer, computer to data calculate and show result；
The sensor fibre includes temperature-measuring optical fiber section and at least one reference optical fiber section；The reference optical fiber section is arranged in perseverance
Under warm environment.
Further, two thermometric channels are realized using a wavelength division multiplexer；
The sensor fibre includes two reference optical fiber sections；Two reference optical fiber sections are separately positioned on two temperature not
In same constant water bath box.
Further, which further includes isochronous controller, the light-pulse generator, the isochronous controller and the data
Capture card is sequentially connected electrically.
The technical solution that embodiments herein provides can include the following benefits：
The present processes are measured using two thermometric channels, eliminate the stream for solving two light path temperature decline coefficients
Journey, to reduce the complexity of temperature demodulation formula and measurement error can also be reduced.In addition, the measurement corresponding to this method
System is less to internal hardware modifications.
It should be understood that above general description and following detailed description is only exemplary and explanatory, not
The application can be limited.
Description of the drawings
The drawings herein are incorporated into the specification and forms part of this specification, and shows the implementation for meeting the application
Example, and the principle together with specification for explaining the application.
Fig. 1 is a kind of flow chart of distributed optical fiber temperature measuring method shown according to an exemplary embodiment.
Fig. 2 is a fixed wave length optical signal generated scattering spectrum figure in a fiber.
Fig. 3 is the raw data plot figure of the rear orientation light acquired in one embodiment.
Fig. 4 is that same optical fiber measures obtained stokes light and anti-Stokes light light path in different time of measuring
Dark current noise value curve graph.
Fig. 5 is that different time measures the original of obtained stokes light and anti-Stokes light to same optical fiber at room temperature
Beginning data graphs.
Fig. 6 is the backward Raman scattering that the pulsed light that two thermometric channels are injected from the both ends of optical fiber causes in same point
Schematic diagram.
Fig. 7 is a kind of block diagram of temperature-measuring system of distributed fibers shown according to an exemplary embodiment.
Fig. 8 is the raw data plot figure of the rear orientation light acquired in one embodiment.
Fig. 9 is the demodulated scheme of initial data in Fig. 8 treated data graphs.
Figure 10 (a) is the temperature curve comparison diagram that two kinds of different temp measuring methods solve under 40 DEG C of environment.
Figure 10 (b) is the temperature curve comparison diagram that two kinds of different temp measuring methods solve under 50 DEG C of environment.
Figure 10 (c) is the temperature curve comparison diagram that two kinds of different temp measuring methods solve under 60 DEG C of environment.
Figure 10 (d) is the temperature curve comparison diagram that two kinds of different temp measuring methods solve under 70 DEG C of environment.
Specific implementation mode
Example embodiments are described in detail here, and the example is illustrated in the accompanying drawings.Following description is related to
When attached drawing, unless otherwise indicated, the same numbers in different drawings indicate the same or similar elements.Following exemplary embodiment
Described in embodiment do not represent all embodiments consistent with the application.On the contrary, they be only with it is such as appended
The example of consistent device and method of some aspects be described in detail in claims, the application.
According to the embodiment of the present application in a first aspect, providing a kind of distributed optical fiber temperature measuring method, this method is applied to DTS
In system.
Fig. 1 is a kind of flow chart of distributed optical fiber temperature measuring method shown according to an exemplary embodiment, including following
Step：
Step 1：Using two thermometric channels, letter is alternately injected into the sensor fibre from the both ends of sensor fibre respectively
Number light；
Step 2：One thermometric channel is acquired in one end of the sensor fibre after the signal light that the end is injected
To scattering light, another described thermometric channel is similarly operated in the other end of the sensor fibre；
Step 3：Collected rear orientation light is handled, temperature demodulation formula is obtained, it is described so as to solve
The temperature value of each point on sensor fibre.
In some embodiments, this method further includes：
Step 301：A part is chosen on the sensor fibre is used as temperature-measuring optical fiber section；
Step 302：At least one reference optical fiber section is chosen in the part that temperature-measuring optical fiber section is not belonging on the sensor fibre,
And the reference optical fiber section is placed under isoperibol.
In some embodiments, described that collected rear orientation light is handled, including：
Step 303：Changed according to the signal value of rear orientation light, isolates the scattering light number for belonging to the temperature-measuring optical fiber section
According to；
Step 304：According to after separation as a result, by the same point in the temperature-measuring optical fiber section in two thermometric channels
On temperature-measuring results carry out location matches.
In some embodiments, described that collected rear orientation light is handled, further include：
Step 305：After carrying out location matches, the scattering light data of the reference optical fiber section is acquired；
Step 306：The undetermined parameter in the temperature demodulation formula is solved according to measurement result, and undetermined parameter is substituted into
In the temperature demodulation formula.
In order to clearly illustrate the scheme of the application, in conjunction with the principle and the prior art of distributed optical fiber temperature measurement
Demodulation scheme carries out expansion explanation.
After in the light injection fibre of a fixed frequency, photon and generation collision and energy transfer in optical fiber generate
Stokes light less than the anti-Stokes light of lambda1-wavelength and higher than former lambda1-wavelength.
Fig. 2 shows scattering spectrum caused by the optical signal of a fixed wave length.Compared with other inelastic scatterings, draw
Scattering optical frequency shift caused by graceful scattering is larger, thus is more convenient for separation；In addition, containing related to temperature in Raman diffused light
Information, therefore can by detach generate Raman diffused light combination temperature demodulate formula come find out occur scattering at temperature
Situation.
In the prior art, based on the distributed temperature measuring system of Raman scattering using based on stokes light and this anti-support
The demodulation scheme of Ke Si light light paths.In this scenario, the Stokes obtained by system acquisition and anti-Stokes optical signal value are full
The following formula of foot：
Wherein, Ias(l, T) and Is(l, T) is the anti-Stokes light and Stokes optical signal value for measuring gained respectively,
The measured value is related with the temperature T of measurement point distance l and measurement point.P0Represent the luminous power of incident light.αp(l),αas
(l),αs(l) light attenuation coefficient of incident light, anti-Stokes light, stokes light is indicated respectively.NasAnd NsBe respectively it is anti-this
Output valve (i.e. dark current noise) of the APD circuits under no input condition in lentor light light path and stokes light light path.
ΓasAnd ΓsIt is the scattering coefficient of anti-Stokes light and stokes light respectively.
In the prior art, the formula of each point temperature value is on solution optical fiber：
The prior art is to carry out measuring temperature by formula (3) and (4).In order to improve precision, these methods need to measure system
The attenuation coefficient of APD is exported in system dark current noise or optical fiber.However, no matter measuring dark current noise or measuring decaying
All there is the defect for being difficult to overcome in coefficient.
As shown in figure 3, in the section that distance is 0~300m, shows sensor fibre and set through optical patchcord insertion thermometric
The optical fiber insertion loss generated when standby；In the subsequent sections 500~1600m, stokes light and anti-Stokes optical signal are strong
Degree is gradually decayed with the promotion of distance.Temperature-measuring optical fiber overall length about 1700m, the output signal value more than measurement distance are
Output valve of the APD circuits under unglazed input condition.Due to include in raw measurement results in two light paths APD circuits without defeated
Output valve in the case of entering, therefore regard the signal value that APD circuits export under no input condition as dark current noise, this is made an uproar
Sound needs to be removed when carrying out temperature demodulation.
As shown in figure 4, illustrating the dark of the obtained stokes light of different time of measuring and anti-Stokes light light path
Current noise value.As it can be seen that dark current noise shows fluctuation in different measurement periods, therefore by NasAnd NsBeing considered as definite value can be right
Measurement result has an impact.
As shown in figure 5, illustrating same optical fiber, different time measures gained initial data at room temperature.To the data in figure
It is fitted the attenuation coefficient α of gained stokes lights(l) fitting result is respectively -4.869e-5And -4.94e-5；And it is anti-this
The attenuation coefficient α of lentor lightas(l) fitting result is -5.568e-5And -5.616e-5.As it can be seen that same optical fiber is after wiring
There is fluctuation in the scattering light attenuation coefficient that different time measures, this fluctuation can cause system when being measured into trip temperature distal end
Generate error.
In order to overcome the defect of above-mentioned prior art, the application to provide a kind of distributed optical fiber temperature measuring method, use
Temperature measurement task is completed in two thermometric channels.In a measurement period, two thermometric channels alternately inject arteries and veins into optical fiber
It washes off, temperature demodulation is carried out according to the initial data that two channel acquisitions arrive.It can remove from this way and solve two light path temperature dampings system
Several flows to reduce the complexity of temperature demodulation formula, and can also reduce measurement error.
The present processes are also done dynamic to dark current noise and are handled；Specific practice is to take the average value of multiple measurement results
As Nas(or Ns), the fluctuation of measurement result can be reduced to the greatest extent in this way.
As shown in fig. 6, (a), (b) indicate pulsed light that two thermometric channels are injected from the both ends of optical fiber same respectively
The backward Raman scattering that point causes.For scattering the anti-Stokes light in light：
Integral element in formula (5) and (6) represents total luminous energy of incident light (P1, P2) and rear orientation light (I1, I2)
Amount decaying, i.e.,：Incident light reaches the light energy decaying from scattering point l from decanting point, along with the scattering light by l backpropagations
Light energy decaying in communication process.Integral part related with l can become whole by following formula in two formula
The optical fiber attenuation constant of optical fiber：
After formula (7) transformation,Only related with the temperature value of tested point, molecular moiety is constant.By formula
In molecular moiety KasIt indicates, thenIt can be written as：
Similarly, for stokes light,It can be reduced to：
Formula (8) and formula (9) are divided by, can be obtained：
Therefore, in embodiments herein, the temperature demodulation formula is：
Wherein：
As undetermined parameter, T (l) are temperature funtion related with tested point position, and k is Boltzmann constant, and h is
Planck's constant, ΔvFor the Raman frequency shift amount of sensor fibre.
Can be by the way that reference optical fiber section be arranged, and place it under isoperibol, undetermined parameter is solved according to measurement result.
Only need a reference optical fiber section that can solve undetermined parameter.
Specific practice is the distance value l of reference optical fiber section0It is known；Since reference optical fiber section is in isoperibol, because
This T (l0) be also known；According to l0The measurement result at place can calculateWithIn l0The value at place substitutes into public
Formula (10) can obtain RS(l0)；Further according to RS(l0) and T (l0) undetermined parameter can be calculated by formula (10)So far, it has asked
Solve complete temperature demodulation formula.
In the entire solution procedure of the embodiment of the present application, key point is, matches same temperature spot to be measured and is surveyed at two
Position in the measurement result in warm channel.
Referring to Fig. 3, in the section that l is 300~500m, there is rising edge twice in the signal value I of the scattering light of acquisition
Saltus step；In the section that l is 500~1600m, signal value I is slowly smoothly reduced；In the section that l is 1600~1700m,
There is the saltus step of rising edge twice again in signal value I.
This is because, optical fiber generates the reflection of generation incident light after being inserted into equipment, with the fiber end face at equipment interface, cause
Stokes light and anti-Stokes light in measurement result are all enhanced, thus the saltus step of multiple rising edge occur in data.
And in temperature-measuring optical fiber section, cutting edge aligned decaying is presented with the increase of distance in scattering light.In the other end of optical fiber, also will appear
The case where end face reflection.
Therefore, it is uprushed phenomenon according to this of proximal fiber and distal end signal, it can be by the temperature-measuring optical fiber part in light path
It is detached from system entirety light path, to realize position of the same temperature measuring point in the measurement result in two different thermometrics channels
Set matching.
In some embodiments, described to isolate the scattering light data for belonging to the temperature-measuring optical fiber section, including：
Investigate the correspondence that signal value I changes as distance value l increases；
Data with stable linear relationship between selection signal value I and distance value l, as belong to the temperature-measuring optical fiber
The scattering light data of section.
Wherein, I be collected rear orientation light signal value (longitudinal axis in Fig. 3), l be occur the back scattering point and
The distance between signal acquisition point is worth (horizontal axis in Fig. 3).
In some embodiments, two thermometric channels are realized using a wavelength division multiplexer, the sensor fibre
Both ends are connected on the same wavelength division multiplexer.To save hardware cost, the utilization ratio of hardware resource.
According to the second aspect of the embodiment of the present application, a kind of temperature-measuring system of distributed fibers is provided, it is above-mentioned to implement
Temperature checking method.
As shown in fig. 7, the system includes light-pulse generator, data collecting card and computer；Further include two thermometric channels, pass
Photosensitive fine, two APD circuits and two signal amplifiers.
The light-pulse generator provides signal light to two thermometric channels；The both ends of the sensor fibre respectively with two
The thermometric channel connection, two thermometric channels are respectively from the both ends of sensor fibre alternating into the sensor fibre
Injection Signal light.
Two thermometric channels respectively pass sequentially through respectively from the both ends collection of scattered light signal of the sensor fibre
One APD circuit and a signal amplifier transmit a signal to the data collecting card；The data collecting card
It is connect with the computer, computer to data calculate and show result of calculation.
The sensor fibre includes temperature-measuring optical fiber section and at least one reference optical fiber section；The reference optical fiber section is arranged in perseverance
Under warm environment.
In some embodiments, two thermometric channels are realized using a wavelength division multiplexer.
In some embodiments, the sensor fibre includes two reference optical fiber sections；Two reference optical fiber section difference
It is arranged in the different constant water bath box of two temperature.Two reference optical fiber sections can be used to solve undetermined parameter twice respectively,
It checks one against another to prevent calculating mistake.
In some embodiments, which further includes isochronous controller, the light-pulse generator, the isochronous controller and institute
Data collecting card is stated to be sequentially connected electrically.
In a specific embodiment, the detail parameters of each device are shown in Table 1 in system.
1 systematic parameter of table
| Capital equipment | Systematic parameter |
| Laser head | Centre wavelength:1550nm, pulse width:10ns |
| Wavelength division multiplexer | Run wavelength:1550,1450,1663nm |
| Data collecting card | 12bit,105MHz |
Referring to the pulsed light that Fig. 7, high-speed pulse light source are generated, sensor fibre is incident on through wavelength division multiplexer；Sensor fibre
In rear orientation light exported to APD circuits through wavelength division multiplexer, APD circuits convert optical signals into electric signal output, through letter
It is sent into data collecting card after the amplification of number amplifier；Output is to computer, computer after data collecting card handles electric signal
It carries out operation and shows final result.Data collecting card is for carrying out double channel data acquisition and processing, data acquisition
Card also controls the work of high-speed pulse light source by isochronous controller.
It is verified using the system for detecting temperature that embodiments herein is provided.Fig. 8 shows be that system acquisition obtains
The initial measurement data arrived, what Fig. 9 was indicated is the gained after the processing of this demodulation schemeWithAs seen from the figure,
The signal strength decline caused by optical fiber attenuation is effectively suppressed.
Figure 10 (a), (b), (c), (d), which show, to be distinguished using the present processes and traditional algorithm in temperature-measuring optical fiber section
Measurement result under 40 DEG C, 50 DEG C, 60 DEG C, 70 DEG C of environment.The binary channels temp measuring method of the application it can be seen from image
Compared with traditional algorithm, the curve of final result is more smooth, especially the survey in temperature rise area part and room temperature area part
Amount temperature, which fluctuates, to be inhibited.
The measurement result that table 2 gives two kinds of different measurement methods compares, and data are optical fiber at 1800~1812m in table
Measurement result.
2 data result of table compares
By the data in table 2 it is found that the present processes and corresponding system, can be reduced to 0.5 by measurement error by 1 DEG C
Within DEG C.
Present applicant proposes twin-channel distributed optical fiber temperature measuring method and systems, to solve the light in Raman temp measuring system
The fluctuation problem of fibre decaying and APD output signals.Experiments verify that scattering of the same optical fiber after wiring when different time measurement
There is fluctuation in light attenuation coefficient, the present processes are by the power attenuation integration part with distance dependent in script temperature demodulation formula
Divide the power attenuation part for being transformed to whole optical fiber, reduce the complexity of temperature demodulation formula and eliminates two light path temperature of solution
Spend the flow of attenuation coefficient.And this method is less to the hardware modifications of internal system, it need not be first to optical fiber in practical thermometric
Attenuation coefficient is calculated.And compared with conventional method, present approach reduces measurement errors.The scheme of the application can be used for endangering
The shelf temperature monitoring of dangerous chemicals warehouse.For hazardous chemical warehouse, the temperature inspection of each stacked location on shelf
Survey can be by realizing Optical Fiber Winding on shelf.
It is understood that same or similar part can mutually refer in the various embodiments described above, in some embodiments
Unspecified content may refer to same or analogous content in other embodiment.
It should be noted that in the description of the present application, term " first ", " second " etc. are used for description purposes only, without
It can be interpreted as indicating or implying relative importance.In addition, in the description of the present application, unless otherwise indicated, the meaning of " multiple "
Refer at least two.
In the description of this specification, reference term " one embodiment ", " some embodiments ", " example ", " specifically show
The description of example " or " some examples " etc. means specific features, structure, material or spy described in conjunction with this embodiment or example
Point is contained at least one embodiment or example of the application.In the present specification, schematic expression of the above terms are not
Centainly refer to identical embodiment or example.Moreover, particular features, structures, materials, or characteristics described can be any
One or more embodiments or example in can be combined in any suitable manner.
Although embodiments herein has been shown and described above, it is to be understood that above-described embodiment is example
Property, it should not be understood as the limitation to the application, those skilled in the art within the scope of application can be to above-mentioned
Embodiment is changed, changes, replacing and modification.
Claims (10)
1. a kind of distributed optical fiber temperature measuring method, which is characterized in that including：
Using two thermometric channels, respectively from the both ends of sensor fibre alternating Injection Signal light into the sensor fibre；
The rear orientation light for the signal light that one thermometric channel is injected in the acquisition of one end of the sensor fibre from the end, separately
One thermometric channel is similarly operated in the other end of the sensor fibre；
Collected rear orientation light is handled, temperature demodulation formula is obtained, so as to solve on the sensor fibre
The temperature value of each point.
2. a kind of distributed optical fiber temperature measuring method according to claim 1, which is characterized in that further include：
A part is chosen on the sensor fibre is used as temperature-measuring optical fiber section；
At least one reference optical fiber section is chosen in the part that temperature-measuring optical fiber section is not belonging on the sensor fibre, and by the reference
Fiber segment is placed under isoperibol.
3. a kind of distributed optical fiber temperature measuring method according to claim 2, which is characterized in that described to collected backward
Scattering light is handled, including：
Changed according to the signal value of rear orientation light, isolates the scattering light data for belonging to the temperature-measuring optical fiber section；
According to after separation as a result, temperature-measuring results by the same point in the temperature-measuring optical fiber section on two thermometric channels
Carry out location matches.
4. a kind of distributed optical fiber temperature measuring method according to claim 3, which is characterized in that described to collected backward
Scattering light is handled, and further includes：
After carrying out location matches, the scattering light data of the reference optical fiber section is acquired；
The undetermined parameter in the temperature demodulation formula is solved according to measurement result, and undetermined parameter is substituted into the temperature demodulation
In formula.
5. a kind of distributed optical fiber temperature measuring method according to claim 4, which is characterized in that the temperature demodulation formula
For：
Wherein：
As undetermined parameter, T (l) are temperature funtion related with tested point position, and k is Boltzmann constant, h Pu Lang
Gram constant, ΔvFor the Raman frequency shift amount of sensor fibre.
6. a kind of distributed optical fiber temperature measuring method according to claim 3, which is characterized in that described isolate belongs to described
The scattering light data of temperature-measuring optical fiber section, including：
Investigate the correspondence that signal value I changes as distance value l increases；
Data with stable linear relationship between selection signal value I and distance value l, as belong to the temperature-measuring optical fiber section
Scatter light data；
Wherein, I is the signal value of collected rear orientation light, and l is between the point and signal acquisition point of the generation back scattering
Distance value.
7. a kind of distributed optical fiber temperature measuring method according to any one of claims 1 to 6, which is characterized in that described in two
Realize that the both ends of the sensor fibre are connected on the same wavelength division multiplexer using a wavelength division multiplexer in thermometric channel.
8. a kind of temperature-measuring system of distributed fibers, including light-pulse generator, data collecting card and computer；It is characterized in that：
Further include two thermometric channels, sensor fibre, two APD circuits and two signal amplifiers；
The light-pulse generator provides signal light to two thermometric channels；The both ends of the sensor fibre respectively with described in two
Thermometric channel connects, and two thermometric channels are alternately injected into the sensor fibre from the both ends of the sensor fibre respectively
Signal light；
Two thermometric channels respectively pass sequentially through one respectively from the both ends collection of scattered light signal of the sensor fibre
The APD circuits and a signal amplifier transmit a signal to the data collecting card；The data collecting card and institute
Computer connection is stated, computer to data calculate and show result；
The sensor fibre includes temperature-measuring optical fiber section and at least one reference optical fiber section；The reference optical fiber section is arranged in constant temperature ring
Under border.
9. a kind of temperature-measuring system of distributed fibers according to claim 8, it is characterised in that：It adopts in two thermometric channels
It is realized with a wavelength division multiplexer；
The sensor fibre includes two reference optical fiber sections；It is different that two reference optical fiber sections are separately positioned on two temperature
In constant water bath box.
10. a kind of temperature-measuring system of distributed fibers according to claim 8, it is characterised in that：The system further includes synchronizing
Controller, the light-pulse generator, the isochronous controller and the data collecting card are sequentially connected electrically.
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|---|---|---|---|---|
| CN111765987A (en) * | 2020-07-09 | 2020-10-13 | 国兴汇金(深圳)科技有限公司 | Distributed multi-section optical fiber temperature measuring method, system and storage medium |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130100984A1 (en) * | 2011-10-24 | 2013-04-25 | Yokogawa Electric Corporation | Opticalfiber temperature distribution measurement apparatus |
| US20160003687A1 (en) * | 2014-07-07 | 2016-01-07 | Yokogawa Electric Corporation | Optical fiber temperature distribution measuring device |
| CN106404217A (en) * | 2016-11-17 | 2017-02-15 | 太原理工大学 | Novel temperature demodulation method based on distributed optical fiber Raman temperature measurement |
| CN107421657A (en) * | 2017-06-28 | 2017-12-01 | 北京石油化工学院 | Raman fiber temperature-sensing system and its noise compensation method |
-
2018
- 2018-04-23 CN CN201810369953.3A patent/CN108760078B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130100984A1 (en) * | 2011-10-24 | 2013-04-25 | Yokogawa Electric Corporation | Opticalfiber temperature distribution measurement apparatus |
| US20160003687A1 (en) * | 2014-07-07 | 2016-01-07 | Yokogawa Electric Corporation | Optical fiber temperature distribution measuring device |
| CN106404217A (en) * | 2016-11-17 | 2017-02-15 | 太原理工大学 | Novel temperature demodulation method based on distributed optical fiber Raman temperature measurement |
| CN107421657A (en) * | 2017-06-28 | 2017-12-01 | 北京石油化工学院 | Raman fiber temperature-sensing system and its noise compensation method |
Non-Patent Citations (1)
| Title |
|---|
| 孙苗: "分布式光纤温度传感系统性能优化及火源定位方法研究", 《中国博士学位论文全文数据库 信息科技辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111765987A (en) * | 2020-07-09 | 2020-10-13 | 国兴汇金(深圳)科技有限公司 | Distributed multi-section optical fiber temperature measuring method, system and storage medium |
| CN111765987B (en) * | 2020-07-09 | 2022-02-25 | 国兴汇金(深圳)科技有限公司 | Distributed multi-section optical fiber temperature measuring method, system and storage medium |
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