CN102636682A - Device and method for measuring large current by optical fiber - Google Patents
Device and method for measuring large current by optical fiber Download PDFInfo
- Publication number
- CN102636682A CN102636682A CN2012101404200A CN201210140420A CN102636682A CN 102636682 A CN102636682 A CN 102636682A CN 2012101404200 A CN2012101404200 A CN 2012101404200A CN 201210140420 A CN201210140420 A CN 201210140420A CN 102636682 A CN102636682 A CN 102636682A
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- magneto
- electric current
- polarization
- circulator
- 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.)
- Pending
Links
Images
Abstract
The invention relates to a device and a method for measuring large current by an optical fiber. A laser source, a circulator, a polarization controller, a magneto-optic crystal and a preserving polarization optical fiber for an optical fiber reflecting mirror are connected in sequence, laser passes through the circulator, the polarization controller and the magneto-optic crystal in sequence to irradiate on the optical fiber reflecting mirror, then, the laser is reflected by the optical fiber reflecting mirror and returns to the polarization controller through the magneto-optic crystal, when the linearly polarized light passes through the magneto-optic crystal under the action of a magnetic field generated by the current, a polarization plane rotates, and the size of the current can be calculated according to the relation between the rotating angle and the current. The measurement device and the measurement method have the advantages of good insulativity, simple structure, small dimension, low manufacture cost, and high measurement accuracy, a piece of equipment can be relatively conveniently installed and overhauled, the operation is safe, the dynamic measurement area is wide, and the sensitivity is high. The optical fiber technology can be effectively combined with the microcomputer technology, and the device and the method for measuring the large current by the optical fiber are applied to a power system, in particular to an integrated automation system of a transformer substation.
Description
Technical field
The present invention relates to a kind of measurement mechanism, particularly a kind of optical fiber is surveyed the measurement mechanism of big electric current.
Background technology
Electric power is the lifeblood of national economy.The measurement of electric current plays a part very important in power industry, and it is provided for metering, control and relay protection information necessary and parameter for electric system.
Transient current in the electrical network has comprised too many failure message; The colleague has proposed higher requirement to the measurement bandwidth of instrument: have the suitable sensitivity scope; And can cover big wide band detection equipment, reproduction fault current that can be complete from power frequency to the megahertz high-frequency signal.
At present, in electric system, mostly adopting with the electromagnetic induction principle for the measurement of high-tension current is the electromagnetic current transducer CT (Current Transformer) on basis.This traditional measuring technique; Many deficiencies have appearred in the continuous increase along with line voltage, and it requires between the high and low pressure end, to provide the electric insulation of complex and expensive; It is more and more heavier that the CT of voltage levels becomes; Price is more and more expensive, and brings difficulty for transportation and installation, add that the magnetic saturation, ferroresonance, the dynamic range that itself exist are little, frequency band is narrow, inflammable and explosive, be subject to disturb.Because electromagnetic current transducer is bulky, quality is heavier, and very inconvenience is installed in transportation, and this causes the installation maintenance of equipment inconvenient.In addition, because electromagnetic transformer is to lean on the electromagnetism transform principle to realize the transmission of energy, therefore, there is potential danger.These problems all impel people to develop more advanced sensor-based system.
In recent years, this advanced techniques field of Fibre Optical Sensor is very active in the world, and the measurement that optical fiber technology is applied to power network current also reaches its maturity.The development of OCT (Optical Current Tranformer) all carries out the transition to the practical application that combines power engineering from breadboard original reason experiment, and some has arrived the stage of on-the-spot extension net test run.
Summary of the invention
The present invention be directed to utilization electromagnetic transformer detection electric current in the electric system; Cost is high, be subject to disturb, bulky problem; Proposed a kind of optical fiber and surveyed the measurement mechanism and the measuring method of big electric current, accuracy is high, transient performance is good, insulation system is simple, size is little, cost is low, upgradability is good.
Technical scheme of the present invention is: a kind of optical fiber is surveyed the measurement mechanism of big electric current; Comprise LASER Light Source, circulator, fall-off meter, Fibre Optical Sensor, Polarization Controller, magneto-optical crystal, fiber reflector; Call Fibre Optical Sensor to the combination of magneto-optical crystal and high-current cable; Described LASER Light Source, circulator, fall-off meter, magneto-optical crystal, fiber reflector link to each other with polarization maintaining optical fibre successively, and laser passes through circulator, Polarization Controller, magneto-optical crystal successively behind fiber reflector, passes through the fiber reflection mirror reflection again; Returning Polarization Controller through magneto-optical crystal, is district to be measured around the magneto-optical crystal.
Said LASER Light Source can be selected the LASER Light Source of 1550nm or 1310nm for use, produces linearly polarized light.
Said circulator can be selected three hole circulators for use, and described fiber reflector is selected the optical fiber of FC-NPC interface for use.
A kind of optical fiber is surveyed the measuring method of big electric current; Comprise that optical fiber surveys the measurement mechanism of big electric current, the polarization tester is connected on the Polarization Controller, through its outgoing polarization state of light of Polarization Controller adjustment; Magneto-optical crystal is placed near the lead that is connected with big electric current; When linearly polarized light passes through magneto-optical crystal under the action of a magnetic field that electric current produces, its plane of polarization will rotate, rotation angle
Be proportional to magnetic field H along the line integral of linearly polarized light, can have by circuital law again through material path:
V
=VNi, wherein V=
Be a constant, be the rotation angle of per unit light path per unit field intensity,
lBe the light path through material, N is the loop number, and i is by being asked current value.
Beneficial effect of the present invention is: optical fiber of the present invention is surveyed the measurement mechanism and the measuring method of big electric current, does not contain iron core, do not have problems such as magnetic saturation, ferroresonance, thereby measurement range is big, and the linearity is good, and frequency response range is wide, and accuracy of measurement is high.Come transmission signals by light, anti-electromagnetic interference capability is strong, and low-pressure side do not exist that Keep Clear-High Voltage because of open circuit produces, and equipment is installed all more convenient security of operation of maintenance.Volume is little, in light weight, range of dynamic measurement is big, and the wide dynamic range of measuring, highly sensitive.Moreover, can also optical fiber technology and microcomputer technology be combined effectively, be applied to electric system, especially comprehensive automation system of transformer substation adapts to the trends such as digitizing, microcomputerization, robotization and optical communication of electric-power metering and relay protection.Under the normal condition, the rated current of operation of power networks is also little, but short-circuit current is very big, and along with the increase of net capacity, the failed shorted electric current is increasing.The current measuring range of electromagnetic current transducer is limited, and the fibre optic current sensor rated current can measure several kiloamperes, and momentary current can measure the hundreds of thousands ampere.
Description of drawings
The measurement mechanism that Fig. 1 surveys big electric current for optical fiber of the present invention detects schematic diagram;
Fig. 2 surveys the measurement mechanism embodiment light path principle figure of big electric current for optical fiber of the present invention.
Embodiment
The measurement mechanism that optical fiber as shown in Figure 1 is surveyed big electric current detects schematic diagram, and device comprises LASER Light Source 1, circulator 2, Polarization Controller 5, magneto-optical crystal 7, fiber reflector 6.Described LASER Light Source 1, circulator 2, Polarization Controller 5, magneto-optical crystal 7, fiber reflector 6 usefulness polarization maintaining optical fibres link to each other successively.Fibre Optical Sensor 4 is combined by magneto-optical crystal 7 and high-current cable.
During practical implementation, described LASER Light Source 1 can be selected the LASER Light Source of 1550nm or 1310nm for use, and purpose is to produce stable linearly polarized light; Described circulator 2 can be selected three hole circulators for use; Described fiber reflector 4 is selected the optical fiber of FC-NPC interface for use; Can not the return laser light light source and can only carry out the detection of polarization state thereby light can only be propagated when light reflects back into circulator 2 after along direction through Polarization Controller 5, described Polarization Controller 5 not only can make the o light e light generation different phase delay of polarized light but also can detect the polarization polarization state of light.
Polarization Controller 5 among Fig. 1, and it both can measure polarization state, can produce phase delay again; After polarized light passes through circulator 2; Polarization Controller 5 just can produce the effect of phase delay, and after light returned through fiber reflector 6, Polarization Controller 5 can be surveyed polarization state of light again.Be the work functions that dotted portion is represented Polarization Controller 5 among Fig. 1, Polarization Controller 5 can be controlled polarization state output 3, can detect the polarization polarization state of light simultaneously.
Described magneto-optical crystal 7 and fiber reflector 6 are to make polarized light behind the magnetic field that produces through big electric current, with the polarization of incident light face a bigger drift angle arranged; Thereby described fiber reflector 6 be make twice of polarized light through magneto-optical crystal 7 twice through magnetic field that excessive electric current produces and then make the plane of oscillation of polarized light produce bigger angular deflection, thereby described polarization maintaining optical fibre is to make the polarization polarization state of light of propagating therein not receive polarized light that stress influence can the stable propagation different polarization states and the different polarization state of accurately measuring polarized light through birefringent compensation.
Fig. 2 is a kind of instance light path principle figure of the present invention.Under the effect in magnetic field, the material that did not have optical activity has originally also produced this phenomenon of optical activity (light vector rotates) and has been called magnetic rotation effect or Faraday effect.Rotating vector
=
material optical activity is ρ; When the light path of then
=
light through material was l, the rotation angle of light polarization face
was:
=
l=
l=V?
l
V=
is a constant here; Physical significance is the rotation angle (diamagnetic substance+, paramagnetic material-) of per unit light path per unit field intensity.
When linearly polarized light passes through magneto-optic memory technique under the action of a magnetic field that electric current produces; Its plane of polarization will rotate, and rotation angle
is proportional to magnetic field H along the line integral of linearly polarized light through material path:
Have by circuital law:
The variation that comes probe current through the size of surveying
.Electric current is directly proportional with
angle, measures
angle and can obtain current i.And it is many more that loop is counted N, and measurement sensitivity is high more.
Principle of work of the present invention is: light makes it the sensitiveest through Polarization Controller 5 its outgoing polarization state of light of adjustment.Magneto-optical crystal 7 is placed near the lead that is connected with big electric current.After the work, computer can be monitored polarization state in real time, measures the electric current in the lead rapidly.When electric current suddenly becomes big or short circuit, through each point at diverse location place size of current come to survey rapidly the particular location that has an accident.
Claims (4)
1. an optical fiber is surveyed the measurement mechanism of big electric current; Comprise LASER Light Source, circulator, Polarization Controller, magneto-optical crystal, fiber reflector, it is characterized in that described LASER Light Source, circulator, fall-off meter, magneto-optical crystal, fiber reflector link to each other with polarization maintaining optical fibre successively; Laser passes through circulator, Polarization Controller, magneto-optical crystal successively behind fiber reflector; Passing through the fiber reflection mirror reflection again, return Polarization Controller through magneto-optical crystal, is district to be measured around the magneto-optical crystal.
2. survey the measurement mechanism of big electric current according to the said optical fiber of claim 1, it is characterized in that said LASER Light Source can be selected the LASER Light Source of 1550nm or 1310nm for use, produce linearly polarized light.
3. survey the measurement mechanism of big electric current according to the said optical fiber of claim 1, it is characterized in that said circulator can be selected three hole circulators for use, described fiber reflector is selected the optical fiber of FC-NPC interface for use.
4. an optical fiber is surveyed the measuring method of big electric current, comprises that optical fiber surveys the measurement mechanism of big electric current, it is characterized in that,
Laser passes through circulator successively to Polarization Controller; Through its outgoing polarization state of light of Polarization Controller adjustment, magneto-optical crystal is placed near the lead that is connected with big electric current, when linearly polarized light passes through magneto-optical crystal under the action of a magnetic field that electric current produces; Its plane of polarization will rotate, rotation angle
Be proportional to magnetic field H along the line integral of linearly polarized light, can have by circuital law again through material path:
V
=VNi, wherein V=
Be a constant, be the rotation angle of per unit light path per unit field intensity,
lBe light path through material, N be the electric current electric wire of flowing through around number of rings, i is by being asked current value.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101404200A CN102636682A (en) | 2012-05-09 | 2012-05-09 | Device and method for measuring large current by optical fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012101404200A CN102636682A (en) | 2012-05-09 | 2012-05-09 | Device and method for measuring large current by optical fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102636682A true CN102636682A (en) | 2012-08-15 |
Family
ID=46621151
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012101404200A Pending CN102636682A (en) | 2012-05-09 | 2012-05-09 | Device and method for measuring large current by optical fiber |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102636682A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105866506A (en) * | 2016-04-01 | 2016-08-17 | 河北大学 | Apparatus and method for measuring conductor current by using magneto-optic material |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101226210A (en) * | 2007-01-18 | 2008-07-23 | 武汉晟思高新技术有限公司 | Reflection type polarization irrespective miniaturization photo-electricity mutual-inductor |
| CN101446600A (en) * | 2008-09-28 | 2009-06-03 | 中国矿业大学 | Optical fiber current sensing device used for monitoring subway stray current |
| CN101846703A (en) * | 2009-03-23 | 2010-09-29 | 徐启峰 | Digital optical fiber current sensor |
-
2012
- 2012-05-09 CN CN2012101404200A patent/CN102636682A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101226210A (en) * | 2007-01-18 | 2008-07-23 | 武汉晟思高新技术有限公司 | Reflection type polarization irrespective miniaturization photo-electricity mutual-inductor |
| CN101446600A (en) * | 2008-09-28 | 2009-06-03 | 中国矿业大学 | Optical fiber current sensing device used for monitoring subway stray current |
| CN101846703A (en) * | 2009-03-23 | 2010-09-29 | 徐启峰 | Digital optical fiber current sensor |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105866506A (en) * | 2016-04-01 | 2016-08-17 | 河北大学 | Apparatus and method for measuring conductor current by using magneto-optic material |
| CN105866506B (en) * | 2016-04-01 | 2018-06-22 | 河北大学 | A kind of device and method that conductor current is measured using magneto-optic memory technique |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109709372B (en) | Closed-loop control device and method for stray current optical fiber sensor of subway/coal mine | |
| CN103235167A (en) | Flexible optical current transformer | |
| CN103134997A (en) | Thunder and lightening detector based on optics principle | |
| Pang et al. | Influencing factors analysis on the detector output signal of fiber optic current transformer with sine modulation | |
| CN106324323A (en) | All-optical-fiber current transformer and current measuring method thereof | |
| Song et al. | A prototype clamp-on magneto-optical current transducer for power system metering and relaying | |
| Kirkham | Current measurement methods for the smart grid | |
| CN203164257U (en) | Flexible optical current transformer | |
| Yoshino | Invited Paper Optical Fiber Sensors For Electric Industry | |
| CN102636682A (en) | Device and method for measuring large current by optical fiber | |
| CN113126007B (en) | Online measurement device and method for leakage magnetic field of oil immersed transformer | |
| Ye et al. | Application research on fiber-optic current sensor in large pulse current measurement | |
| CN109406852A (en) | A kind of high current current detection sensor based on all -fiber mutual inductor | |
| CN110726862A (en) | Integrated optical sensor probe for measuring broadband high-amplitude current | |
| CN111198290B (en) | Optical fiber type current transformer | |
| Zavoda et al. | Sensors for smart grids | |
| CN207215897U (en) | A kind of high current current detection sensor based on all -fiber transformer | |
| KR101098666B1 (en) | Optical Electric-Field Sensors | |
| CN102590584A (en) | Large current detecting device based on optical means | |
| Wang et al. | Study on Long-term operation stability of fiber optical current transformer based on faraday effect | |
| CN102590585A (en) | Measuring device for large current of power grid | |
| Ahmed | Performance evaluation of optical fiber current transformer based over-current protection | |
| CN205139230U (en) | Fiber optic current sensor | |
| CN113124935B (en) | Composite sensor for magnetic leakage temperature of oil-immersed transformer and measuring method | |
| Li et al. | Design and evaluation of a current differential protection scheme incorporating a fiber optical current sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20120815 |