CN206818784U - The optical fiber current sensing device measured in real time based on birefringence - Google Patents

The optical fiber current sensing device measured in real time based on birefringence Download PDF

Info

Publication number
CN206818784U
CN206818784U CN201720729824.1U CN201720729824U CN206818784U CN 206818784 U CN206818784 U CN 206818784U CN 201720729824 U CN201720729824 U CN 201720729824U CN 206818784 U CN206818784 U CN 206818784U
Authority
CN
China
Prior art keywords
polarization
optical fiber
measured
current sensing
wave plate
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201720729824.1U
Other languages
Chinese (zh)
Inventor
何祖源
马麟
刘银萍
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Jiaotong University
Original Assignee
Shanghai Jiaotong University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Jiaotong University filed Critical Shanghai Jiaotong University
Priority to CN201720729824.1U priority Critical patent/CN206818784U/en
Application granted granted Critical
Publication of CN206818784U publication Critical patent/CN206818784U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Abstract

A kind of optical fiber current sensing device measured in real time based on birefringence, including:Polarization beam apparatus, the polarization-maintaining laser being sequentially connected, spatial polarization controller, optical fiber device, photo-coupler, polarization analysis device and data acquisition unit, wherein:Polarization-maintaining laser, spatial polarization device and optical fiber device are sequentially connected, the output end of optical fiber device is connected with photo-coupler, the output end of photo-coupler is connected with polarization analysis device and polarization beam apparatus respectively, data acquisition unit gathers the polarization state data of polarization analysis device and the light intensity data of polarization beam apparatus respectively, so as to obtain the birefringence size of sensor fibre to be measured and faraday's deflection angle;The utility model is designed reasonably, the accurate measurement to faraday's deflection angle is realized, have directive significance to the reliability and accuracy for improving fibre optic current sensor practical application.

Description

The optical fiber current sensing device measured in real time based on birefringence
Technical field
The utility model relates to a kind of technology in fiber-optic current sensor field, is specifically a kind of real-time based on birefringence The optical fiber current sensing device of measurement.
Background technology
Traditional current sensor based on galvanomagnetic-effect there are problems that in actual use, such as magnetic saturation, iron The problem of in terms of the securities such as magnetic resonance, dynamic range are small, the big weight weight of volume, cost height, installation inconvenience, explosive.Optical fiber Current sensor becomes an important research in current sense field because its sensing principle can't have above mentioned problem Direction.Realize all -fiber magnetic field sensor principle have it is a variety of, such as Faraday effect, magnetostrictive effect and magnetic fluid material Deng wherein based on the fibre optic current sensor of Faraday effect because it turns into for the intuitive of curent change and easily detection property A focus in research field.
Fibre optic current sensor based on Faraday effect mainly faces two problems in actual applications:First, tradition is single The Verdet constant of mode fiber is very low, limits the sensitivity of current sensor, and conventional solution method is to use Gao Feierde The doped fiber of constant.Second, the stability and reliability of fibre optic current sensor are low.The linear birefrigence of single-mode fiber is held very much It is vulnerable to the influence of some extraneous unpredictable factors, for example temperature, stress, bends and distort, this will weakens faraday's effect Should.Because the linear birefrigence of optical fiber is changed at random by various environmental perturbations and is not easy to measure, traditional fiber current sense Device assumes that linear birefrigence is not present in optical fiber when demodulating faraday's deflection angle, thus have ignored linear birefrigence and faraday is revolved The degeneration of optic angle, cause measured sensitivity distortion.
Utility model content
The utility model for prior art can not real-Time Compensation birefringence influenceed by environment random perturbation the problem of, carry Go out a kind of optical fiber current sensing device measured in real time based on birefringence, by sensor fibre input polarization to be measured and output The measurement of polarization state, the birefringence size of sensor fibre to be measured is obtained, it is inclined further according to the light intensity signal compensation faraday of fast and slow axis The degeneration of corner, can accurate measurement faraday's deflection angle.
The utility model is achieved through the following technical solutions:
A kind of optical fiber current sensing device measured in real time based on birefringence is the utility model is related to, including:Polarization beam splitting Device, the polarization-maintaining laser being sequentially connected, spatial polarization controller, optical fiber device, photo-coupler, polarization analysis device and data acquisition Device, wherein:Polarization-maintaining laser, spatial polarization device and optical fiber device are sequentially connected, and the polarization state of flashlight occurs under magnetic fields Change, the output end of optical fiber device is connected with photo-coupler, the output end of photo-coupler respectively with polarization analysis device and polarization beam splitting Device is connected, and the output end of the input of data acquisition unit respectively with polarization analysis device and polarization beam apparatus is connected.
Described spatial polarization controller includes:The wave plate of the wave plate of the λ being coaxially disposed/2, two λ/4 and two collimating mirrors, its In:Two collimating mirrors are symmetricly set in the both sides of the wave plate of λ/2, and the wave plate of two λ/4 is respectively symmetrically arranged at the wave plate of λ/2 and collimating mirror Between.
Described optical fiber device includes:DC source and sensor fibre to be measured, wherein:The both positive and negative polarity of DC source respectively with biography to be measured It is photosensitive fine connected.
Described polarization analysis device includes:The wave plate of 1 point of 4 beam splitter, λ/4,0 ° of polarizer, 45 ° of polarizers and four balances Photodetector, wherein:1 point of 4 beam splitter exports four road light, directly inputs balance photodetector all the way;Sequentially input all the way 0 ° of polarizer and balance photodetector;45 ° of polarizers and balance photodetector are sequentially input all the way;Sequentially input all the way λ/ 4 wave plates, 45 ° of polarizers and balance photodetector.
Described polarization beam apparatus includes:Polarization beam apparatus and two optical-electrical converters, wherein:The output of polarization beam apparatus Output two-way orthogonal crossed polarized light in end is simultaneously separately input into two optical-electrical converters.
Described data acquisition unit includes:6 channel data capture cards and two balance photodetectors.
Described data acquisition unit obtains the light intensity signal of sensor fibre fast and slow axis to be measured by polarization beam apparatus.
Described sensor fibre to be measured is 50~2000m standard single-mode fibers.
Described polarization analysis device directly measures the polarization state of the output of polarization-maintaining laser, passes through spatial polarization controller Transmission matrix obtains the input polarization of sensor fibre to be measured, the output of the sensor fibre output end to be measured measured with vibration analysis device Polarization state is contrasted, you can obtains the linear birefrigence size of sensor fibre to be measured;The linear birefrigence of sensor fibre to be measured Two light intensity signals of the sensor fibre fast and slow axis to be measured obtained with reference to polarization beam apparatus, you can it is double to obtain sensor fibre to be measured Faraday's deflection angle after refraction compensation.
Described input polarization is calculated by the Jones matrix of spatial polarization controller.
The calculation formula of described faraday's deflection angle is:Wherein:P1And P2Point Not Wei sensor fibre fast and slow axis to be measured light intensity, θ is faraday's deflection angle, and Δ δ is the linear birefrigence of sensor fibre to be measured.
Technique effect
Compared with prior art, the utility model is monitored in real time by adding polarization analysis device in sensor fibre end to be measured The output polarization state of sensor fibre to be measured, the real-time birefringence of sensor fibre to be measured is obtained to compensate faraday's deflection angle, it is real Now to the accurate measurement of faraday's deflection angle, the reliability of fibre optic current sensor is improved.
Brief description of the drawings
Fig. 1 is optical fiber current sensing device schematic diagram;
Fig. 2 is polarization analysis device schematic diagram;
Fig. 3 is that the relation of birefringence-compensated front and rear faraday's deflection angle and size of current under the smaller state of fiber birefringence is shown It is intended to;
Fig. 4 is that the relation of birefringence-compensated front and rear faraday's deflection angle and size of current under fiber birefringence fair state is shown It is intended to;
Fig. 5 is that the relation of birefringence-compensated front and rear faraday's deflection angle and size of current under the larger state of fiber birefringence is shown It is intended to;
Fig. 6 is relation schematic diagram of the degeneration with birefringence size of rotation effect when ignoring birefringence;
In figure:It is 1 polarization-maintaining laser, 2 spatial polarization controllers, 3 DC sources, 4 sensor fibres to be measured, 5 photo-couplers, 6 inclined Shake the wave plate of the wave plate of beam splitter, 7 optical-electrical converters, 8 polarization analysis devices, 9 data acquisition units, 10 collimating mirrors, 11 λ/4,12 λ/2,13 Flashlight, 141 point of 4 beam splitter, 150 ° of polarizers, 1645 ° of polarizers, 17 balance photodetectors.
Embodiment
As shown in figure 1, the present embodiment includes:Polarization beam apparatus, the polarization-maintaining laser 1 being sequentially connected, spatial polarization control Device 2, optical fiber device, photo-coupler 5, polarization analysis device 8 and data acquisition unit 9, wherein:Continuous lines caused by polarization-maintaining laser 1 are inclined Flashlight 13 passes through spatial polarization device input optical fibre device, and the polarization state of flashlight 13 changes under magnetic fields, optical fiber device Flashlight 13 that the polarization state of output changes divides for two-way light by photo-coupler 5, all the way into polarization analysis device 8, separately Enter polarization beam apparatus all the way, data acquisition unit 9 carries out data acquisition to polarization analysis device 8 and polarization beam apparatus respectively.
Described polarization-maintaining laser 1 exports continuous line polarisation, to ensure the flashlight 13 of input space Polarization Controller 2 Polarization state is stable.
Described spatial polarization controller 2 includes:The wave plate 11 of the λ being coaxially disposed/2 wave plate, 12, two λ/4 and two collimations Mirror 10, wherein:Two collimating mirrors 10 are symmetricly set in the both sides of the wave plate 12 of λ/2, the wave plate 11 of two λ/4 be respectively symmetrically arranged at λ/ Between 2 wave plates 12 and collimating mirror 10.
Described optical fiber device includes:DC source 3 and sensor fibre to be measured 4, wherein:The both positive and negative polarity of DC source 3 is respectively with treating Sensor fibre 4 is surveyed to be connected.
As shown in Fig. 2 described polarization analysis device 8 is integrated device, including:1 point of 4 beam splitter 14, λ/11,0 ° of 4 wave plate 15,45 ° of polarizers 16 of the polarizer and four balance photodetectors 17, wherein:1 point of 4 beam splitter 14 exports four road light, all the way Directly input balance photodetector 17;0 ° of polarizer 15 and balance photodetector 17 are sequentially input all the way;It is defeated successively all the way Enter 45 ° of polarizers 16 and balance photodetector 17;λ/4 wave plate, 11,45 ° of polarizers 16 are sequentially input all the way and balance photoelectricity is visited Survey device 17.
The gain of described balance photodetector 17 is consistent.
Described polarization beam apparatus includes:Polarization beam apparatus 6 and two optical-electrical converters 7, wherein:Polarization beam apparatus 6 is defeated Go out the orthogonal crossed polarized light of two-way, two optical-electrical converters 7 of input are converted to electric signal and do follow-up data processing respectively.
Described data acquisition unit 9 includes:6 channel data capture cards and two balance photodetectors 17.
Described data acquisition unit 9 obtains the light intensity signal of the fast and slow axis of sensor fibre 4 to be measured by polarization beam apparatus.
The present embodiment is related to the birefringent method of measurement in real time based on said apparatus, and polarization analysis device 8 directly measures guarantor The polarization state of the output of inclined laser 1, regard flashlight 13 as sense light to be measured by the polarization state after spatial polarization controller 2 The input polarization of fibre 4, the output polarization state of the output end of sensor fibre to be measured 4 measured with reference to polarization analysis device 8 are i.e. available The linear birefrigence size of sensor fibre 4 to be measured;What the linear birefrigence of sensor fibre 4 to be measured obtained in conjunction with polarization beam apparatus Two light intensity signals of the fast and slow axis of sensor fibre 4 to be measured, you can obtain sensor fibre 4 to be measured it is birefringence-compensated after faraday Deflection angle.
Due to the wave plate anglec of rotation in spatial polarization controller 2, it is known that described input polarization passes through spatial polarization The Jones matrix of controller 2 is calculated.
The calculation formula of described faraday's deflection angle is:Wherein:P1And P2Point Not Wei the fast and slow axis of sensor fibre 4 to be measured light intensity, θ is faraday's deflection angle, and Δ δ is the linear birefrigence of sensor fibre 4 to be measured.
The wavelength of flashlight 13 that the polarization-maintaining laser 1 of the present embodiment exports is 1550nm, and sensor fibre 4 to be measured is that 250m is mono- Mode fiber.
The length of described sensor fibre to be measured 4 can be adjusted flexibly:Under high-current test environment, it is adapted to shorter optical fiber Length;Under the conditions of low current, it is adapted to longer fiber lengths.
Described photo-coupler 5 is 50/50 photo-coupler.
The birefringence of described sensor fibre to be measured 4 can be changed by adjusting the curved shape of optical fiber.
As shown in Fig. 3~Fig. 5, Ω1Faraday's deflection angle that measurement obtains during to ignore linear birefrigence, Ω2For this implementation Example considers faraday's deflection angle that measurement obtains during linear birefrigence, and slope (slope) is the sensitivity of measurement.It is determined that it is double Under refraction, adjustment space Polarization Controller 2, so as to change the input polarization of sensor fibre 4 to be measured, the spirit of fibre-optical sensing device Sensitivity can also change.As seen from the figure, total phase shift of faraday's deflection angle and sensor fibre to be measured 4 is linear with the increase of electric current Change, when total phase shift change is big, annihilation effect of the linear birefrigence to rotation effect is further serious.When total phase shift is 22.5 °, Using the sensitivity of traditional demodulation method 96.9% is have dropped with respect to the present embodiment;When total phase shift is 108.73 °, traditional demodulation The sensitivity of method drops to 49% with respect to the present embodiment, and sensitivity improves 1 times.
As shown in fig. 6, point represents experimental result, line representation theory result;θ1For birefringence-compensated preceding faraday's deflection Angle, θ2To pass through birefringence-compensated faraday's deflection angle.When birefringence is close to 0 °, the approximation that traditional demodulation method measures is partially Corner and actual deflection angle are basically identical;When birefringence is larger, at such as 108.73 °, deflection angle that traditional demodulation method measures Sensitivity have dropped 51%, and experimental result is coincide substantially with theoretical calculation.
Above-mentioned specific implementation can by those skilled in the art on the premise of without departing substantially from the utility model principle and objective with Different modes carries out local directed complete set to it, and the scope of protection of the utility model is defined by claims and not by above-mentioned specific Implementation is limited, and each implementation in the range of it is by the constraint of the utility model.

Claims (7)

  1. A kind of 1. optical fiber current sensing device measured in real time based on birefringence, it is characterised in that including:Polarization beam apparatus, according to Secondary connected polarization-maintaining laser, spatial polarization controller, optical fiber device, photo-coupler, polarization analysis device and data acquisition unit, its In:Polarization-maintaining laser, spatial polarization device and optical fiber device are sequentially connected, and the output end of optical fiber device is connected with photo-coupler, optical coupling The output end of device is connected with polarization analysis device and polarization beam apparatus respectively, the input of data acquisition unit respectively with polarization analysis device It is connected with the output end of polarization beam apparatus.
  2. 2. optical fiber current sensing device according to claim 1, it is characterized in that, described spatial polarization controller includes: The wave plate of the wave plate of the λ being coaxially disposed/2, two λ/4 and two collimating mirrors, wherein:Two collimating mirrors are symmetricly set in the wave plate of λ/2 Both sides, the wave plate of two λ/4 are respectively symmetrically arranged between the wave plate of λ/2 and collimating mirror.
  3. 3. optical fiber current sensing device according to claim 1, it is characterized in that, described optical fiber device includes:DC source and Sensor fibre to be measured, wherein:The both positive and negative polarity of DC source is connected with sensor fibre to be measured respectively.
  4. 4. optical fiber current sensing device according to claim 1, it is characterized in that, described polarization analysis device includes:1 point 4 The wave plate of beam splitter, λ/4,0 ° of polarizer, 45 ° of polarizers and four balance photodetectors, wherein:1 point of 4 beam splitter exports four tunnels Light, balance photodetector is directly inputted all the way;0 ° of polarizer and balance photodetector are sequentially input all the way;It is defeated successively all the way Enter 45 ° of polarizers and balance photodetector;The wave plate of λ/4,45 ° of polarizers and balance photodetector are sequentially input all the way.
  5. 5. optical fiber current sensing device according to claim 1, it is characterized in that, described polarization beam apparatus includes:Polarization Beam splitter and two optical-electrical converters, wherein:The orthogonal crossed polarized light of output end output two-way of polarization beam apparatus is simultaneously It is separately input into two optical-electrical converters.
  6. 6. optical fiber current sensing device according to claim 1, it is characterized in that, described data acquisition unit includes:6 passages Data collecting card and two balance photodetectors.
  7. 7. optical fiber current sensing device according to claim 3, it is characterized in that, described sensor fibre to be measured is 50~ 2000m standard single-mode fibers.
CN201720729824.1U 2017-06-22 2017-06-22 The optical fiber current sensing device measured in real time based on birefringence Active CN206818784U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201720729824.1U CN206818784U (en) 2017-06-22 2017-06-22 The optical fiber current sensing device measured in real time based on birefringence

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201720729824.1U CN206818784U (en) 2017-06-22 2017-06-22 The optical fiber current sensing device measured in real time based on birefringence

Publications (1)

Publication Number Publication Date
CN206818784U true CN206818784U (en) 2017-12-29

Family

ID=60761328

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201720729824.1U Active CN206818784U (en) 2017-06-22 2017-06-22 The optical fiber current sensing device measured in real time based on birefringence

Country Status (1)

Country Link
CN (1) CN206818784U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109142840A (en) * 2018-09-18 2019-01-04 江门市新会区炎泰电子有限公司 A kind of current measuring method and its all -fiber leakage current protector based on dual wavelength

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109142840A (en) * 2018-09-18 2019-01-04 江门市新会区炎泰电子有限公司 A kind of current measuring method and its all -fiber leakage current protector based on dual wavelength
CN109142840B (en) * 2018-09-18 2023-07-25 江门市新会区炎泰电子有限公司 Current measurement method and all-fiber leakage current protector thereof

Similar Documents

Publication Publication Date Title
CN103076155B (en) Optical fiber Verdet constant measurement system on basis of double optical paths
CN103226162B (en) Optical waveguide voltage sensor based on double light path compensation
CN102279095B (en) Device for reducing influence of birefringent chromatic dispersion on polarization coupling measurement of polarization maintaining optical fiber
CN107179431A (en) The optical fiber current sensing device and its method measured in real time based on birefringence
CN104459267B (en) Thin film type all-fiber current transformer with temperature compensation
CN105091877A (en) Rotation sensing method based on polarization state of light and optical gyroscope thereof
CN101968508B (en) All-fiber current sensor and polarization state control method thereof
CN107091950A (en) The reflective electric current and magnetic field sensor of TEMP are integrated with based on optical sensing principle
CN206696332U (en) A kind of optical current mutual inductor
CN105203857A (en) Electro-optic quadratic effect-based spatial strong electric field measurement system
CN105182093A (en) Strong electric field sensor possessing temperature compensation and measurement method thereof
CN206818784U (en) The optical fiber current sensing device measured in real time based on birefringence
CN201047858Y (en) High intensity effect type full optical fiber reflection type optical current mutual inductor
CN110007125A (en) Double light path optical current sensor
CN103196655B (en) A kind of polarization maintaining optical fibre Verdet constant measuring apparatus and method
CN101907650A (en) Magneto-optical balance type optical fiber current transformator
CN209746025U (en) Current measurement system based on double fiber bragg gratings
CN202305631U (en) Optical-fiber-type current transformer
CN106597061A (en) Sagnac type fiber current sensor and current detection method thereof
CN106291040A (en) Magneto-opitcal current transducer
CN102590608A (en) Environment temperature compensation heavy current measurement system based on fiber polarization detection
CN205786792U (en) A kind of all-fiber current transformator based on optical fiber temperature sensor
CN103344199B (en) Square-wave frequency modulation realizes the method for space angle measurement
Yi et al. A novel bulk-glass optical current transducer having an adjustable multiring closed-optical-path
CN110749551B (en) Coal mine optical fiber current sensor based on polarization analysis

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant