CN104237607A - Dual-path detection type current magnetic field sensor based on micro optical fiber coupler - Google Patents
Dual-path detection type current magnetic field sensor based on micro optical fiber coupler Download PDFInfo
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- CN104237607A CN104237607A CN201410547333.6A CN201410547333A CN104237607A CN 104237607 A CN104237607 A CN 104237607A CN 201410547333 A CN201410547333 A CN 201410547333A CN 104237607 A CN104237607 A CN 104237607A
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- 239000013307 optical fiber Substances 0.000 title claims abstract description 69
- 238000001514 detection method Methods 0.000 title claims abstract description 28
- 230000008878 coupling Effects 0.000 claims abstract description 53
- 238000010168 coupling process Methods 0.000 claims abstract description 53
- 238000005859 coupling reaction Methods 0.000 claims abstract description 53
- 229910052751 metal Inorganic materials 0.000 claims abstract description 33
- 239000002184 metal Substances 0.000 claims abstract description 33
- 230000008859 change Effects 0.000 claims abstract description 24
- 238000000034 method Methods 0.000 claims abstract description 23
- 230000007704 transition Effects 0.000 claims abstract description 5
- 230000007246 mechanism Effects 0.000 claims description 51
- 230000000694 effects Effects 0.000 claims description 17
- 239000000835 fiber Substances 0.000 claims description 12
- 210000004705 lumbosacral region Anatomy 0.000 claims description 12
- 230000035945 sensitivity Effects 0.000 claims description 9
- 238000005259 measurement Methods 0.000 claims description 4
- 238000012545 processing Methods 0.000 claims description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 claims description 2
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 239000010959 steel Substances 0.000 claims description 2
- 230000003287 optical effect Effects 0.000 abstract description 9
- 238000010408 sweeping Methods 0.000 abstract 1
- 230000008569 process Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000036039 immunity Effects 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
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Abstract
The invention discloses a dual-path detection type current magnetic field sensor based on a micro optical fiber coupler. The dual-path detection type current magnetic field sensor comprises the micro optical fiber coupler add a metal wire. The micro optical fiber coupler is manufactured from two single-mode optical fiber by use of a flame sweeping method, and comprises a uniform waist region, two cone-shaped transition region, two input ends and two output ends; the two input ends of the micro optical fiber coupler are together connected with one end of the metal wire, while the two output ends of the micro optical fiber coupler are together connected with the other end of the metal wire. The metal wire is pulled to be bent under the action of a current or a magnetic field so that the micro optical fiber coupler is stressed in the length direction; as the diameter of the uniform waist region of the micro optical fiber coupler is relatively small and the length and the refractive index of a coupling region are very sensitive to the action of force, the power of the two output ends of the coupler obviously changes along with the change of the externally applied current or magnetic field, and therefore, sensing detection on the current or the magnetic field can be realized by use of a dual-path detection method. The dual-path detection type current magnetic field sensor based on the micro optical fiber coupler is capable of improving the utilization rate of the optical energy and eliminating the influence of the power disturbance of the incident light.
Description
Technical field
The present invention relates to the application of optical fiber, be specifically related to research and the preparation thereof of Fibre Optical Sensor, especially provide a kind of two-way based on micro optical fiber coupling mechanism to detect formula current field sensor.
Background technology
Optical fiber sensing technology be before general more than 30 years rise novel research field, it mainly utilize optical fiber and with the light for transport vehicle come perception outer signals change new technique.Along with the development in epoch, optical fiber sensing technology is kept up to date further, and a large amount of senser elements based on micro optical fiber making arises at the historic moment, and is much employed for commercialization.Micro optical fiber senser element has a lot of unexistent advantage of other commonplace components, such as miniaturization, and low cost is lightweight, electromagnetism interference, and is easy to carry out being connected etc. with other devices in fiber optic network.
Micro optical fiber electric current and magnetic field sensor are the high-tech products integrating multiple subject, relate to many-sided knowledge.Due to the demand of miniaturization, high precision, easily making, be one of direction of making great efforts to the profound level of its theory, many-sided research and actual product commercialization always.Generally speaking, micro optical fiber electric current and magnetic field sensor can run into more challenge and development afterwards.
Traditional large cost of current field sensor weight is higher, and some devices containing magnetic material exist magnetic hysteresis and magnetic saturation phenomenon, and some senser elements based on resonator cavity are difficult to make and encapsulation.Therefore, produce a small low-cost, electromagnetism interference, highly sensitive, be easy to the electric current that connects in fiber optic network and magnetic field sensor, be still a very large challenge.
Summary of the invention
The object of this invention is to provide a kind of current field sensor based on micro optical fiber coupling mechanism, the thermal expansion utilizing electric current to produce and Ampère force traction metal wire microbend, make micro optical fiber coupling mechanism be subject to the effect of power at length direction, thus realize the accurate measurement to electric current and magnetic field.
The technical solution used in the present invention is:
Two-way based on micro optical fiber coupling mechanism detects formula current field sensor, comprise micro optical fiber coupling mechanism and metal wire, micro optical fiber coupling mechanism utilizes flame to sweep ignition method by two single-mode fibers and makes, and comprises an even lumbar region, two conical transition zones, two input ends and two output terminals; Two input ends of described micro optical fiber coupling mechanism are connected with one end of metal wire jointly, and two output terminals are connected with the other end of metal wire jointly.
The length of described even lumbar region is 6 millimeters to 15 millimeters, and the diameter of even lumbar region place simple optical fiber is 1 micron to 5 microns.
Further, described metal wire adopts copper cash or aluminum steel.
Utilize above-mentioned two-way to detect the measuring method of formula current field sensor, adopt two-way detection method, its concrete steps comprise:
(1) metal wire is connected with direct supply, tunable laser sources one of them input end with described micro optical fiber coupling mechanism is connected; Two output terminals of described micro optical fiber coupling mechanism are connected with power-measuring device respectively,
(2) direct supply is opened, electric current produces thermal expansion effects, traction metal wire microbend, makes described micro optical fiber coupling mechanism be subject to the effect of power at length direction, thus the power division of described micro optical fiber coupling mechanism two output terminals along with the change of impressed current, significantly change can occur; Method of difference is adopted to carry out data processing to the performance number measured: the difference of the power of two measurement of output end and the ratio of sum of the two are designated as Γ, Γ can change along with current synchronization, pass through linear fit, the change of the Γ value that unitary current is caused, be defined as current sensitivity, utilize two-way detection method to obtain the size of electric current by the change observing Γ thus, realize the sensing detection to electric current;
(3) metal wire connected with direct supply and be placed in the magnetic field that magnetic field generator produces, fixing direct current size, magnetic field generator is utilized to add magnetic field in metal wire vertical direction, now produce Ampère force, same traction metal wire microbend, described micro optical fiber coupling mechanism is made to be subject to the effect of power at length direction, then according to the method in step (2), pass through linear fit, the change of the Γ value that unit field is caused, be defined as magnetic field sensitivity, utilize two-way detection method can obtain the size in magnetic field by the change observing Γ thus, realize the sensing detection to magnetic field.
Above measuring method, is two-way detection method, utilizes two-way detection method to improve the utilization factor of luminous energy, and eliminates the adverse effect of light source power disturbance for system.
Two-way based on micro optical fiber coupling mechanism of the present invention detects formula current field sensor senses principle: the effect of thermal expansion produced due to electric current or the effect traction metal wire microbend of Ampère force, micro optical fiber coupling mechanism is made to be subject to the effect of power at length direction, because the diameter of the even lumbar region of micro optical fiber coupling mechanism is less, the length of coupled zone and refractive index very responsive to the effect of power, thus the power meter of coupling mechanism two output terminals detects that watt level along with the change in impressed current or magnetic field, significantly change can occur, thus the sensing detection utilizing two-way detection method to realize electric current or magnetic field.
The invention has the beneficial effects as follows:
(1) should detect formula current field sensor based on the two-way of micro optical fiber coupling mechanism utilizes one end of coupling mechanism to have two delivery outlets, and two output powers all proportional relations with incident optical power, so the stability of incident optical power directly has influence on the sensitivity of whole device, therefore two output powers are carried out to the method for difference data processing of difference divided by sum of the two of the two, the dependence of system to input optical power can be eliminated, strengthen light source disturbance immunity, improve Stability and dependability, and improve the utilization factor of luminous energy.
(2) the present invention utilizes micro optical fiber coupling mechanism to prepare highly sensitive electric current and magnetic field sensor first, with low cost, and security is high, be easy to be applied in fiber optic network.
Accompanying drawing explanation
Fig. 1 is based on the detection schematic diagram of the two-way detection formula current field sensor of micro optical fiber coupling mechanism;
The simulation schematic diagram of Fig. 2 micro optical fiber coupling mechanism;
(a) zone of transition of Fig. 3 micro optical fiber coupling mechanism and the microphotograph of (b) lumbar region;
The transmitted light spectrogram of Fig. 4 sensor of the present invention Port3 under two different electric currents;
After the process of Fig. 5 sensor method of difference of the present invention, with the fitted figure of curent change;
The transmitted light spectrogram of Fig. 6 sensor Port3 of the present invention under two different magnetic fields;
After the process of Fig. 7 sensor method of difference of the present invention, with the fitted figure of changes of magnetic field, electric current fixes 0.08A.
Embodiment
Below in conjunction with accompanying drawing and specific implementation method to invention has been further instruction, represent feature of the present invention with clear.
Fig. 1 is the detection schematic diagram of the two-way detection formula current field sensor based on micro optical fiber coupling mechanism, comprising: direct supply 1, metal wire 2, tunable laser sources 3, power meter 4, magnetic field generator and micro optical fiber coupling mechanism 5; Direct supply 1 is connected with metal wire 2, and tunable laser sources 3 connects a single-mode fiber of micro optical fiber coupling mechanism 5 one end, and two single-mode fibers of micro optical fiber coupling mechanism 5 other end, namely two output terminals are connected with power meter 4 respectively.
First remove with the coat of optical fiber wire-stripping pliers by single-mode fiber in experiment, two optical fiber abut against together side by side, then adopt flame sweep ignition method by two single-mode fiber drawing-downs and molten together, move specific length and specific diameter to always, make micro optical fiber coupling mechanism 5, finally micro optical fiber coupling mechanism 5 and metal wire 2 are stretched, be bonded on metal wire 2 by the single-mode optical fiber pigtail at coupling mechanism 5 two ends by cementing agent 6, metal wire 2 is fixed on fixture 7.The length of micro optical fiber coupling mechanism 5 lumbar region of the present embodiment about 10 millimeters.Because the lumbar region part of micro optical fiber coupling mechanism 5 exists the coupling between two single-mode fibers, so the light passed into from an optical fiber can be divided into two-way in coupled zone, export from two output terminals, thus can both reading be read on two power meters 4.
Fig. 2 shows the simulation schematic diagram of micro optical fiber coupling mechanism.Wherein light is from the Port1 input single-mode fiber, and be coupled in coupled zone, light exports from Port3 and Port4 with certain distribution simultaneously.
Fig. 3 illustrates the zone of transition of micro optical fiber coupling mechanism of the present invention and the microphotograph of lumbar region.
During measurement, open direct supply 1, direct current is passed into by metal wire 2, change galvanic size, effect traction metal wire 2 microbend of the thermal expansion that electric current produces, micro optical fiber coupling mechanism 5 is made to be subject to the effect of power at length direction, because the diameter of the even lumbar region of micro optical fiber coupling mechanism 5 is less, the length of coupled zone and refractive index very responsive to the effect of power, thus the power meter 4 of coupling mechanism two output terminals detects that watt level along with the change of impressed current, significantly change can occur, thus utilizes the sensing detection of two-way detection method realization to electric current.Secondly, fixing direct current size, magnetic field generator is utilized to add magnetic field in metal wire 2 vertical direction, now effect traction metal wire 2 microbend of Ampère force, coupling mechanism 5 length direction is subject to the effect of power, detect the change of the watt level on two power meters 4, utilize the sensing detection of two-way detection method realization to magnetic field.
Fig. 4 is the transmitted light spectrogram of this sensor Port3 under two different electric currents.Show in figure for larger electric current, transmitted spectrum moves to left.For the Single wavelength 1543nm of tunable laser sources 3, the output power of Port3 reduces.
Fig. 5 is after this sensor method of difference process, with the fitted figure of curent change.Pass into wavelength 1543nm, as can be seen from the figure good linear relationship, the sensitivity of current sense can be obtained by linear fit for-1.0867A
-1.
Fig. 6 is the transmitted light spectrogram of this sensor Port3 under two different magnetic fields, and electric current fixes 0.08A.Show in figure for larger magnetic field, transmitted spectrum moves to left.For Single wavelength 1543nm, the output power of Port3 reduces.
Fig. 7 is that after this sensor method of difference process, with the fitted figure of changes of magnetic field, electric current fixes 0.08A.Pass into wavelength 1543nm, as can be seen from the figure good linear relationship, as calculated, when electric current is 0.08A, magnetic field sensing sensitivity is-0.0496mT
-1.
Characteristic of the present invention is: 1. adopt difference numerical process: two output terminal power all proportional relations with incident optical power, so the stability of incident optical power directly has influence on the sensitivity of whole device, after difference processing, incident optical power is mathematically disappeared, and namely eliminates the impact of incident optical power stability on sensitivity; 2. actively make use of two output terminals, maximum using luminous energy, take full advantage of the advantage of coupling mechanism.
Claims (4)
1. the two-way based on micro optical fiber coupling mechanism detects formula current field sensor, comprise micro optical fiber coupling mechanism and metal wire, it is characterized in that, micro optical fiber coupling mechanism utilizes flame to sweep ignition method by two single-mode fibers and makes, and comprises an even lumbar region, two conical transition zones, two input ends and two output terminals; Two input ends of described micro optical fiber coupling mechanism are connected with one end of metal wire jointly, and two output terminals are connected with the other end of metal wire jointly.
2. the two-way based on micro optical fiber coupling mechanism according to claim 1 detects formula current field sensor, and it is characterized in that, the length of described even lumbar region is 6 millimeters to 15 millimeters, and the diameter of even lumbar region place simple optical fiber is 1 micron to 5 microns.
3. the two-way based on micro optical fiber coupling mechanism according to claim 1 and 2 detects formula current field sensor, it is characterized in that, described metal wire adopts copper cash or aluminum steel.
4. utilize the two-way based on micro optical fiber coupling mechanism described in claim 1 to detect the measuring method of formula current field sensor, it is characterized in that, adopt two-way detection method, concrete steps comprise:
(1) metal wire is connected with direct supply, tunable laser sources one of them input end with described micro optical fiber coupling mechanism is connected; Two output terminals of described micro optical fiber coupling mechanism are connected with power-measuring device respectively,
(2) direct supply is opened, electric current produces thermal expansion effects, traction metal wire microbend, makes described micro optical fiber coupling mechanism be subject to the effect of power at length direction, thus the power division of described micro optical fiber coupling mechanism two output terminals along with the change of impressed current, significantly change can occur; Method of difference is adopted to carry out data processing to the performance number measured: the difference of the power of two measurement of output end and the ratio of sum of the two are designated as Γ, Γ can change along with current synchronization, pass through linear fit, the change of the Γ value that unitary current is caused, be defined as current sensitivity, utilize two-way detection method to obtain the size of electric current by the change observing Γ thus, realize the sensing detection to electric current;
(3) metal wire connected with direct supply and be placed in the magnetic field that magnetic field generator produces, fixing direct current size, magnetic field generator is utilized to add magnetic field in metal wire vertical direction, now produce Ampère force, same traction metal wire microbend, described micro optical fiber coupling mechanism is made to be subject to the effect of power at length direction, then according to the method in step (2), pass through linear fit, the change of the Γ value that unit field is caused, be defined as magnetic field sensitivity, utilize two-way detection method can obtain the size in magnetic field by the change observing Γ thus, realize the sensing detection to magnetic field.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104597311A (en) * | 2015-01-30 | 2015-05-06 | 南京大学 | Current sensor and measuring method based on graphene-microfiber circular resonant cavity |
| CN111579847A (en) * | 2020-04-30 | 2020-08-25 | 杭州电子科技大学 | Double-enhancement current sensing system based on micro fiber junctions and magnetic fluid |
| CN114019430A (en) * | 2021-11-01 | 2022-02-08 | 南京大学 | Micro-optical fiber magnetic field sensor based on magnetostrictive material and preparation method |
Families Citing this family (1)
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| CN106526227B (en) * | 2016-09-30 | 2019-01-29 | 南京大学 | Micro- flow sensor and its measurement method based on micro optical fiber coupler |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104597311B (en) * | 2015-01-30 | 2017-04-19 | 南京大学 | Current sensor and measuring method based on graphene-microfiber circular resonant cavity |
| CN111579847A (en) * | 2020-04-30 | 2020-08-25 | 杭州电子科技大学 | Double-enhancement current sensing system based on micro fiber junctions and magnetic fluid |
| CN114019430A (en) * | 2021-11-01 | 2022-02-08 | 南京大学 | Micro-optical fiber magnetic field sensor based on magnetostrictive material and preparation method |
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