CN201963358U - Intrinsically safe distributed allfiber underground monitoring instrument - Google Patents
Intrinsically safe distributed allfiber underground monitoring instrument Download PDFInfo
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- CN201963358U CN201963358U CN2010206791225U CN201020679122U CN201963358U CN 201963358 U CN201963358 U CN 201963358U CN 2010206791225 U CN2010206791225 U CN 2010206791225U CN 201020679122 U CN201020679122 U CN 201020679122U CN 201963358 U CN201963358 U CN 201963358U
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Abstract
The utility model relates to an intrinsically safe distributed allfiber underground monitoring instrument, which is composed of a monitoring terminal, an underground distribution optical fiber sensing terminal and transmission cables for connecting the monitoring terminal and the underground distribution optical fiber sensing terminal, wherein the underground parts are all composed of optical fiber passive devices, do not consist any electronic components, require any power supplies, and radiate any electromagnetic waves, thereby being intrinsically safe. The monitoring instrument senses various dynamic information of surroundings by utilizing underground sensing cables and transmits the information back to ground for analysis, processing and truly restoring by the monitoring terminal, thereby realizing real time monitoring to the various dynamic information and identification, location and early warning to abnormal information, and being applicable to various mines, in particular to the field of safe production and accidents rescue of the mines under inflammable and explosive conditions.
Description
Technical field
The utility model relates to the monitoring equipment under the mine, relate in particular to the distributed full optical fiber underground monitoring equipment that a kind of its down-hole part does not comprise any electronic devices and components, need not electric energy supply thereby essential safety, can be applicable to all mines, safety in production that especially inflammable and explosive environment goes down into a mine and accident are rescued the field.
Background technology
For a long time, with the colliery is the underground mine of typical case's representative, geological conditions is complicated and changeable, often be subjected to the threat of disasters such as gas, water, fire, coal dust, landslide, add that technical equipment falls behind relatively, workforce's quality is generally not high, safety management is not enough, cause various accidents to take place frequently, underground work personnel's life security is constituted a serious threat.The how effectively normal operation of various systems and the dangerous information in the environment under the monitor well, and mine disaster rescues after taking place timely and effectively, become mine safety and produced most important task.
Existing downhole monitoring system, no matter be sensor, data collecting system, or data transmission system, form by electronic devices and components, its operation needs supply of electric power, and these electronic devices and components are in the medium-term and long-term operation of down-hole adverse circumstances, inevitably produce phenomenons such as short circuit, electric spark, local pyrexia, itself just has inborn potential safety hazard such downhole monitoring system, especially in the higher zone of methane gas concentration, has more danger.
Summary of the invention
At the above-mentioned defective of existing downhole monitoring system, the purpose of this utility model provides the distributed full optical fiber underground monitoring equipment that a kind of its down-hole part does not comprise any electronic devices and components, need not electric energy supply thereby essential safety.
The utility model for the technical scheme that solves its technical problem and adopt is:
A kind of distributed full optical fiber underground monitoring equipment of essential safety, by monitoring terminal, transmission cable and distributing optical fiber sensing terminal are formed, monitoring terminal is positioned at aboveground, the distributing optical fiber sensing terminal is positioned at the down-hole, transmission cable connects monitoring terminal and distributing optical fiber sensing terminal, it is characterized in that, described distributing optical fiber sensing terminal is by the light pretreatment module, sensing optic cable and reflection end are formed, described smooth pretreatment module is formed by connecting by two sections optical patchcords side by side by two fiber couplers, wherein be manufactured with fibre delay line on one section optical patchcord, one end of light pretreatment module connects transmission cable, the other end connects sensing optic cable, and the other end of sensing optic cable is connected to reflection end.It is characterized in that, described monitoring terminal is formed output precision by light source module and light shunt module, light source module connects the input that the light shunt module connects transmission cable again, detection and amplification module, data acquisition module, data processing module and display module constitute input module, the output termination of transmission cable detects and amplification module, detects to be connected data acquisition module, data processing module and display module according to this with amplification module.It is characterized in that described sensing optic cable is made up of optical fiber, enhancement Layer, topping.
Monitoring terminal is placed in the aboveground monitoring machine room; Transmission cable one end is connected monitoring terminal, and the other end enters the down-hole, is connected to the light pretreatment module in the distributing optical fiber sensing terminal; By the transmission cable that the light pretreatment module other end extends out, lay along mine laneway, at the terminal connection reflection end of transmission cable.
Working mechanism of the present utility model is:
Monitoring terminal is launched optical signal by transmission cable to the distributing optical fiber sensing terminal; The various multidate informations that produce in the subsurface environment by various media, form disturbance to sensing optic cable, thereby cause the minor variations of the inner light path of sensing optic cable; Through after the reflection of reflection end, the former road of the optical signal of this change in optical path length passes back to monitoring terminal, finishes functions such as opto-electronic conversion, signals collecting, analyzing and processing, demonstration and warning in monitoring terminal inside; In monitoring terminal,, can reproduce the change information of disturbing source through time-domain analysis to inverse signal; Frequency-domain analysis through to inverse signal can position disturbing source, thereby realizes the real-time monitoring to the various multidate informations in down-hole.
In the utility model, the various multidate informations that produce in the described subsurface environment, be meant the various information that can make sensing optic cable produce time dependent small geometrical deformation, speak, walk, knock sound wave that wall, seismic wave, current etc. produce, vibration, shock wave etc. including, but not limited to the personnel in the pit.
In the utility model, described various media are meant air, soil layer, water of down-hole etc., by these media, the various multidate informations in the environment can be delivered to sensing optic cable.
In the utility model, described disturbance is meant the time dependent small geometrical deformation that sensing optic cable produces.
Compared with the prior art, the utlity model has following advantage:
1. essential safety.Part in the down-hole in the utility model all is made up of the passive fiber device, do not have and cause dangerous physical basis, no current passes through when work, the non-radiating electromagnetic wave, be not subjected to electromagnetic interference yet, can not produce phenomenons such as electric spark, electric leakage, short circuit, heating, but long-term work is in highdensity methane gas and do not have danger.Requiring under the extremely strict condition, native system also can accomplish not contain any metal ingredient in the part of down-hole.
2. green energy conservation, low-carbon environment-friendly is particularly useful for large-scale mine.Only need lower powered electric energy supply at aboveground monitoring terminal in the utility model, all by optical fibre device transmission luminous energy, energy loss is minimum for the down-hole part, can need not the outside resources supply and long-time running in the down-hole reaches tens of kilometers scope.
3. suitable environment is wide.The utility model all is made up of the passive fiber device in the part of down-hole, can moist, under water, long-term stable operation under the various adverse circumstances such as high temperature, corrosion.
4. distributed sensing.The sensing components and parts of core only are a sensing optic cable in the utility model, only need sensing optic cable is laid along underworkings, and any position of whole optical cable all can be used as sensor, finishes the sensing and the positioning function of disturbance information in the surrounding environment simultaneously.
5. assist the function of rescuing after having safety in production monitoring and accident simultaneously.The utility model can monitored personnel in the pit's duty at ordinary times, after accidents such as permeable, landslide, even the distributing optical fiber sensing terminal is buried, the personnel in the pit still can be by beaing modes such as native stone to aboveground monitoring terminal unidirectional delivery information.
6. combine with optical communication system.The utility model can be by the method for single-core fiber in the common user communication optical cable and the compound use of various other systems based on fiber optic cable communications of down-hole.
Description of drawings
Fig. 1 is a theory structure sketch of the present utility model;
Fig. 2 is the structural representation of monitoring terminal in the utility model, and wherein block arrows is an optical path direction, and hollow arrow is the circuit direction;
Fig. 3 is the structural representation of the distributing optical fiber sensing terminal of the utility model embodiment;
Fig. 4 is the spectrum curve figure that is used in the utility model specific embodiment the disturbing source location.
Among the figure, 10. monitoring terminal, 20. transmission cables, 30. distributing optical fiber sensing terminals, 11. light source module, 12. smooth shunt module, 13. detect and amplification module, 14. data acquisition module, 15. data processing modules, 16. display modules, 31. the light pretreatment module, 32. sensing optic cables, 33. reflection ends, 34. disturbing source, 311.2 * 2 fiber couplers, 312.2 * 2 fiber couplers, 313. fibre delay line, 314. optical patchcords, 315. optical patchcords.
The specific embodiment
Below in conjunction with the drawings and specific embodiments the utility model is elaborated.
A kind of distributed full optical fiber downhole monitoring system of essential safety, by monitoring terminal, transmission cable and distributing optical fiber sensing terminal are formed, monitoring terminal is positioned at aboveground, the distributing optical fiber sensing terminal is positioned at the down-hole, transmission cable connects monitoring terminal and distributing optical fiber sensing terminal, it is characterized in that, described distributing optical fiber sensing terminal is by the light pretreatment module, sensing optic cable and reflection end are formed, described smooth pretreatment module is formed by connecting by two sections optical patchcords side by side by two fiber couplers, wherein be manufactured with fibre delay line on one section optical patchcord, one end of light pretreatment module connects transmission cable, the other end connects sensing optic cable, and the other end of sensing optic cable is connected to reflection end.It is characterized in that, described monitoring terminal is formed output precision by light source module and light shunt module, light source module connects the input that the light shunt module connects transmission cable again, detection and amplification module, data acquisition module, data processing module and display module constitute input module, the output termination of transmission cable detects and amplification module, detects to be connected data acquisition module, data processing module and display module according to this with amplification module.It is characterized in that described sensing optic cable is made up of optical fiber, enhancement Layer, topping.
Embodiment:
As shown in Figure 1, the distributed full optical fiber downhole monitoring system of described a kind of essential safety is made up of monitoring terminal 10, transmission cable 20 and distributing optical fiber sensing terminal 30 3 parts, wherein, monitoring terminal 10 is positioned at aboveground, distributing optical fiber sensing terminal 30 is positioned at the down-hole, transmission cable 20 connects monitoring terminal 10 and distributing optical fiber sensing terminal 30, and the distributing optical fiber sensing terminal 30 that is positioned at the down-hole need not supply of electric power, and being positioned at aboveground monitoring terminal 10 has supply of electric power.
In conjunction with Fig. 2 and Fig. 3, present embodiment comprises monitoring terminal 10, transmission cable 20, distributing optical fiber sensing terminal 30, and transmission cable 20 two ends connect monitoring terminal 10 and distributing optical fiber sensing terminal 30 respectively.Monitoring terminal 10 as shown in Figure 2, comprising light source module 11, light shunt module 12, detection and amplification module 13, data acquisition module 14, data processing module 15, display module 16; Distributing optical fiber sensing terminal 30 is as Fig. 3, comprising light pretreatment module 31, sensing optic cable 32, reflection end 33; Comprise 2 * 2 fiber couplers, 311,2 * 2 fiber couplers 312, fibre delay line 313, optical patchcord 314, optical patchcord 315 in the light pretreatment module 31, wherein optical patchcord 314,315 connects 2 * 2 fiber couplers 311 and 2 * 2 fiber couplers 312, and fibre delay line 313 is produced on the optical patchcord 314.
When using the utility model, monitoring terminal 10 is positioned over aboveground safety monitoring center, and transmission cable 20 1 ends connect aboveground monitoring terminal 10, and the other end gos deep into the down-hole, draw two core fibres (transmitting and receiving optical signal respectively), insert distributing optical fiber sensing terminal 30.Suppose the specific requirement according to underground monitoring, the tunnel of definition N bar branch needs distributing optical fiber sensing terminal 30, then should comprise 2N fiber number in the transmission cable 20 at least.
The light path feature of present embodiment is: the continuous light wave that the light source module 11 of wide spectrum sends, enter light shunt module 12 after, be N light component by mean allocation, be assigned to respectively in N the distributing optical fiber sensing terminal 30 by transmission cable 20.In distributing optical fiber sensing terminal 30, light energy is divided into 2 light components by 2 * 2 fiber couplers 311, and the light component that wherein enters wire jumper 315 directly enters in 2 * 2 fiber couplers 312; The light component that enters wire jumper 314 is through fibre delay line 313, produced time-delay τ after, enter 2 * 2 fiber couplers 312 again; Wire jumper 314, two light components in 315 enter sensing optic cable 32 after merging in 2 * 2 fiber couplers 312, therefore, at sensing optic cable 32 internal communications are two light components with time difference τ, these two light components are through after the propagation forward of certain distance, run into the reflection end 33 of sensing optic cable 32 ends, after sensing optic cable 32 former road directions, propagate after being reflected, to 2 * 2 fiber couplers 312, originally two light components that had a time difference τ are by the wire jumper 314 by having the fibre delay line 313 and not have wire jumper 315 of delaying time respectively after the beam split once more, and enter in 2 * 2 fiber couplers 311 and to merge, enter transmission cable 20 after the merging, and get back in the monitoring terminal 10 by transmission cable 20.
In distributing optical fiber sensing terminal 30, produce 4 following light components altogether: have time-delay τ when (a) propagating forward, not time-delay when returning backward; Not time-delay has time-delay τ when (b) propagating forward when returning backward; (c) propagation does not all have time-delay with returning backward forward; (d) propagation all has time-delay τ with returning backward forward.Because light source module 11 adopts broad spectrum light source, make the coherence length of light wave less than the length of fibre delay line 313, dimension, in above-mentioned 4 light components, have only light component (a) and (b) satisfy coherent condition, light wave after produce interfering enters and detects and amplification module 13, enters successively in data acquisition module 14, data processing module 15 and the display module 16 after changing the signal of telecommunication into.
The working mechanism of present embodiment is as follows:
Various multidate informations in distributing optical fiber sensing terminal 30 surrounding environment can be regarded the disturbance of 34 pairs of sensing optic cables 32 of disturbing source as, thereby the phase place of propagates light in the sensing optic cable 32 is modulated.For example, the aerial propagation of sound wave will cause that the air ambient acoustic pressure changes, and acoustic pressure changes will cause the minor variations of sensing optic cable 32 inside as the geometry of elastomeric bare fibre; And for example, the mechanical wave of propagating in wall also can cause the variation of sensing optic cable attached thereto 32 internal optical fiber geometries.According to the elasto-optical effect of optical fiber, these disturbances will cause the minor variations of fiber lengths and refractive index, thus the light that makes the inside of optical fibre transmission, at light path time to time change through passing by in the sensing optic cable 32.
Environment produces under the situation of disturbances sensing optic cable 32 around, light component (a) and (b) after passing through sensing optic cable 32, and the light path of passing by is identical.
Produce under the situation of disturbance at sensing optic cable 32 certain some place at disturbing source 34, the first time in the source 34 that is disturbed when light wave is propagated forward, modulation when the back kick that is reflected after the light wave in the optical fiber runs into reflection end 33 casts to disturbing source 34, was modulated for the second time.If the time interval between twice modulation is T, the distance between disturbing source 34 residing positions and the reflection end 33 is L, obviously has following formula to set up between T and the L:
(1)
N wherein
EffBe the effective refractive index of optical fiber, c is the light velocity in the vacuum.
Under the common situation, the disturbing signal that disturbing source 34 produces comprises a plurality of spectrum components, therefore, to the phase perturbation of light wave, can be regarded as the stack of the disturbance component of a plurality of sinusoidal frequencies.Only consider that now its medium frequency is the disturbance component of ω, then have:
Wherein
Be certain constantly owing to being subjected to the phase shift that frequency is the light wave that produces of the disturbance of ω,
Be the constant relevant with disturbing source and optic fibre characteristic.Because aforesaid two bundle coherent lights with time difference τ have all passed through twice modulation, at t, t+T, t+ τ, t+ τ+T constantly, τ is the time difference that two-beam successively passes through disturbance point, then has respectively:
Wherein
For by frequency being the phase shift of the light of disturbance component in the interference system that t causes constantly of ω.Formula (3) has only considered that frequency is the disturbance component of ω, if consider the disturbance of all frequencies, because the disturbance that disturbing source 34 is implemented is stackable, therefore obtains:
In the formula (4)
Be total phase shift that 34 pairs of light waves of disturbing source produce, m
iBe to be ω by frequency
iA weight coefficient of disturbing signal amplitude size decision, and
Then be that the light phase that whole disturbing source produces moves.
Two light components that carry disturbance information form interference signal and enter monitoring terminal 10, and the time domain output signal that system obtains is:
Wherein (ω t) is time dependent power output, I to P
0Be and a relevant constant of input optical power size, ψ is that visual is constant by the initial phase of whole system decision; Therefore, the AC compounent of output only with interference system in phase shift
(relevant with disturbance) is relevant.Can try to achieve the disturbance information that disturbing source 34 produces by formula (5), thereby realize true reduction multidate information in transmission cable 32 surrounding environment.
Next the frequency domain information that system is obtained is analyzed, by formula (3) as can be known: when
The time, the amplitude corresponding with frequencies omega is always zero on the frequency domain spectra, and the amplitude of this feature forcing frequency of performance ω correspondence is significantly less than the amplitude of all side frequencies on frequency domain spectra, has so-called " trap point ".In order to distinguish, need to consider following two kinds of situations:
I. work as
The time,
(wherein k is a natural number); With (1) formula substitution, the note characteristic frequency is f
Null(k), then obtain a series of characteristic frequency:
Thus formula as seen, the position of disturbing source (representing) and characteristic frequency f with L
Null(k) corresponding closely, its size is:
Through the analyzing and processing of monitoring terminal 10, can with
Demodulation is come out.
Be the variable of a time t, it is carried out spectrum analysis, can find out damaged frequency f
Null(k), thereby calculate the L value, judge the position of disturbing source 34, be implemented in the distributed sensing on whole piece sensing optic cable 32 length according to (7) formula.
II. work as
The time,
Also there be " trap point " in (wherein k is a natural number).But because τ is produced by fibre delay line 313, that can regulate is very little, makes first characteristic frequency f ' (1) corresponding with it just very big, and promptly on the frequency spectrum upper curve, corresponding trap point position is away from the origin of coordinates; Therefore, just can avoid f ' (k) to f as long as choose suitable τ value
Null(k) interference.
The follow-up processing procedure of embodiment is as follows: in monitoring terminal 10, the optical signal that returns at first enters and detects and amplification module 13, optical signal is carried out processing such as opto-electronic conversion, low noise amplification, high-pass filtering, change into the signal of telecommunication that is fit to arithmetic processor collection and computing; In data acquisition module 14, finish functions such as analog-to-digital conversion, high-speed data acquisition; In data processing module 15, finish functions such as demodulates information reduction, frequency spectrum conversion, pattern-recognition, intellectual analysis, data storage; Finally in display module 16, the various information that monitor are shown, locate and report to the police (early warning) in real time.In monitoring terminal 10, comprise necessary software systems.
Provide the concrete parameter of embodiment:
In the present embodiment, used broad spectrum light source 11 is SO3-B type super radiation light emitting tube (SLD) the type stabilized light source that 44 research institutes of parent company of electronics group produce; 2 * 2 fiber couplers 311 and 312 are the single-mode optical-fibre coupler that Wuhan post and telecommunications academy produces, and two fiber couplers are average beam split; Photodetector is that 44 models of being produced are the InGaAs photodetector of GT322C500; The optical fiber of used sensing optic cable 32 is the G652 type single-mode fiber that the U.S. " healthy and free from worry " produces; Optical patchcord 314,315 is the FC/PC type single-mode fiber jumper that Wuhan post and telecommunications academy produces; Reflection end 33 is that reflectivity is greater than 95% at optical fiber connector AM aluminum metallization film production.
In the present embodiment, when disturbing source 34 in the position on the sensing optic cable 32 when the distance L of reflection end 33 is 24050 meters, the corresponding damaged situation of frequency spectrum as shown in Figure 4, first damaged spectrum position is corresponding to L=24033 rice, second damaged spectrum position is corresponding to L=24059 rice, the 3rd damaged spectrum position is corresponding to L=24038 rice, and average uncertainty is 0.05%.
The front provides the description to preferred embodiment, so that any technician of this area can use or utilize the utility model.Various modifications to these embodiment are conspicuous to those skilled in the art, can be applied to other embodiment to total principle described here and not use creativeness.Thereby, the embodiment shown in the utility model will be not limited to here, and the wide region of principle that should disclose and new features according to meeting here.
Claims (3)
1. the distributed full optical fiber underground monitoring equipment of an essential safety, by monitoring terminal, transmission cable and distributing optical fiber sensing terminal are formed, monitoring terminal is positioned at aboveground, the distributing optical fiber sensing terminal is positioned at the down-hole, transmission cable connects monitoring terminal and distributing optical fiber sensing terminal, it is characterized in that, described distributing optical fiber sensing terminal is by the light pretreatment module, sensing optic cable and reflection end are formed, described smooth pretreatment module is formed by connecting by two sections optical patchcords side by side by two fiber couplers, wherein be manufactured with fibre delay line on one section optical patchcord, one end of light pretreatment module connects transmission cable, the other end connects sensing optic cable, and the other end of sensing optic cable is connected to reflection end.
2. the distributed full optical fiber underground monitoring equipment of a kind of essential safety according to claim 1, it is characterized in that, described monitoring terminal is formed output precision by light source module and light shunt module, light source module connects the input that the light shunt module connects transmission cable again, detection and amplification module, data acquisition module, data processing module and display module constitute input module, the output termination of transmission cable detects and amplification module, detects to be connected data acquisition module, data processing module and display module according to this with amplification module.
3. the distributed full optical fiber underground monitoring equipment of a kind of essential safety according to claim 1 is characterized in that described sensing optic cable is made up of optical fiber, enhancement Layer, topping.
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| CN2010206791225U CN201963358U (en) | 2010-12-24 | 2010-12-24 | Intrinsically safe distributed allfiber underground monitoring instrument |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102854541A (en) * | 2011-09-13 | 2013-01-02 | 代剑华 | Passive method and passive system with function of positioning for acquiring downhole information after disasters |
| CN104496132A (en) * | 2014-11-20 | 2015-04-08 | 徐云飞 | Oilfield oil sludge treatment novel process |
| CN105701977A (en) * | 2016-05-02 | 2016-06-22 | 漳浦县圆周率工业设计有限公司 | Double-layer tube used for earthquake alarm |
-
2010
- 2010-12-24 CN CN2010206791225U patent/CN201963358U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102854541A (en) * | 2011-09-13 | 2013-01-02 | 代剑华 | Passive method and passive system with function of positioning for acquiring downhole information after disasters |
| CN104496132A (en) * | 2014-11-20 | 2015-04-08 | 徐云飞 | Oilfield oil sludge treatment novel process |
| CN104496132B (en) * | 2014-11-20 | 2016-09-07 | 徐云飞 | Oil field oil sludge New Process for Treatment |
| CN105701977A (en) * | 2016-05-02 | 2016-06-22 | 漳浦县圆周率工业设计有限公司 | Double-layer tube used for earthquake alarm |
| CN105701977B (en) * | 2016-05-02 | 2018-01-26 | 漳浦县圆周率工业设计有限公司 | A kind of earthquake alarm bimetallic tube |
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Granted publication date: 20110907 Termination date: 20111224 |