SI9011362A - Fibre optic arrangement for measuring the strength of an electric current - Google Patents
Fibre optic arrangement for measuring the strength of an electric current Download PDFInfo
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- SI9011362A SI9011362A SI9011362A SI9011362A SI9011362A SI 9011362 A SI9011362 A SI 9011362A SI 9011362 A SI9011362 A SI 9011362A SI 9011362 A SI9011362 A SI 9011362A SI 9011362 A SI9011362 A SI 9011362A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/24—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using light-modulating devices
- G01R15/245—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using light-modulating devices using magneto-optical modulators, e.g. based on the Faraday or Cotton-Mouton effect
- G01R15/246—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using light-modulating devices using magneto-optical modulators, e.g. based on the Faraday or Cotton-Mouton effect based on the Faraday, i.e. linear magneto-optic, effect
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
- Communication Cables (AREA)
Abstract
Description
NAPRAVA Z OPTIČNIM VLAKNOM ZA MERJENJE JAKOSTI ELEKTRIČNEGA TOKAOPTICAL FIBER DEVICE FOR MEASURING ELECTRICAL POWER
Področje tehnike, kamor spada izum.FIELD OF THE INVENTION
Izum se nanaša na napravo z optičnimi vlakni za merjenje jakosti električnega toka in spada v področje elektrotehnike oziroma v področje proizvodnje instrumentov za merjenje jakosti toka.The invention relates to an optical fiber device for measuring the current of electricity and falls within the field of electrical engineering or the field of production of instruments for measuring the current.
Tehnični problem.A technical problem.
Tehnični problem, ki se rešuje z izumom, je naslednji: kako realizirati napravo z optičnimi vlakni za merjenje jakosti električnega toka, ki izkorišča prednosti zavrtenja optičnega vlakna in istočasno zmanjšuje vse nadaljnje merilne napake?The technical problem to be solved by the invention is the following: how to realize an optical fiber device for measuring the electric current that takes advantage of the rotation of the optical fiber and at the same time reduces any further measurement errors?
Stanje tehnike.The state of the art.
Naprave te vrste uporabljajo zlasti v visokonapetostnih postrojenjih za merjenje toka v vodnikih pod visokonapetostnim potencialom. Ker so prevodniki svetlobnih valov narejeni iz stekla, ki je, kot je poznano, dober izolator, ni problemov pri izolaciji kazalnih aparatov, ki so povezani z zemeljskim potencialom, pri prevodnikih pod visokonapetostnim potencialom, kjer je treba izmeriti tok in ga pokazati.In particular, devices of this type are used in high-voltage installations for measuring current in conductors under high-voltage potential. Since light wave conductors are made of glass, which is known to be a good insulator, there is no problem in isolating pointing devices that are connected to ground potential in conductors under high voltage potential where current is to be measured and indicated.
Iz DE-AS 22 61 151 je poznana naprava, pri kateri se svetlobni vir usmerja preko polarizatorja na polprevodniško ploščo. Polarizirana svetloba prihaja odtod v optično vlakno (tam imenovano “prevodnik svetlobnega vala”), ki je deloma navito v tuljavo, v čigar osi se nahaja visokonapetostni prevodnik, v katerem teče tok, ki ga je treba izmeriti. Tuljava iz vlakna ima na svojem koncu odbojno površino ali pa je tam postavljeno zrcalo. Polarizirana svetloba prehaja skozi vsa optična vlakna, pri čemer pride znotraj tuljavnega dela vlakna, na osnovi Faradayevega efekta do obračanja polarizacijske ravnine v odvisnosti od magnetnega polja, ki ga povzroča tok, ki teče v prevodniku. Na koncu tuljave se svetlobni snop odbije in prehaja še enkrat skozi tuljavo, pri čemer pride do nadaljnjega obračanja polarizacijske ravnine. V svoji polarizacijski ravnini obrnjena svetloba izstopa iz optičnega vlakna, prehaja skozi polprevodniško ploščo in pride v napravo za vrednotenje, ki ugotavlja in pokaže kot med polarizacijsko ravnino svetlobe, ki vstopa v optično vlakno in polarizacijsko ravnino svetlobe, ki izstopa iz vlakna, pri čemer je velikost kota proporcionalna integralu po poti jakosti magnetnega polja.DE-AS 22 61 151 discloses a device in which a light source is directed through a polarizer to a semiconductor board. Polarized light comes from there into an optical fiber (called a "waveguide conductor"), which is partly wound into a coil whose axis contains a high voltage conductor in which the current to be measured flows. The fiber coil has a reflective surface at its end or a mirror is placed there. Polarized light passes through all the optical fibers, and within the coil part of the fiber, based on the Faraday effect, the polarization plane is reversed depending on the magnetic field caused by the current flowing in the conductor. At the end of the coil, the light beam reflects off and passes through the coil once more, causing the polarization plane to turn further. In its polarization plane, the inverted light exits the optical fiber, passes through the semiconductor panel, and enters the evaluation device, which detects and shows the angle between the polarization plane of light entering the optical fiber and the polarizing plane of light exiting the fiber, the magnitude of the angle proportional to the integral along the path of the magnetic field strength.
Iz DE - AS 28 35 794 je prav tako poznana naprava z optičnim vlaknom za merjenje jakosti električnega toka z uporabo Faradayevega efekta, pri čemer magnetno polje, ki obkroža prevodnik, skozi katerega teče tok, vpliva na stanje polarizacije svetlobe, ki jo pot vodi skozi jedro optičnega vlakna, ki ga prevodnik obsega v obliki navitja. V nasprotju z DE - AS 22 61 151 se pri tej napravi, ki na enem koncu nima odbojne površine, na enem koncu svetloba že spaja, na drugem pa spet razdvaja, pri čemer mora imeti tuljava navita iz optičnih vlaken dvojno število navojev, tako da obdrži enak kot obračanja polarizacijske ravnine, ker svetloba prehaja skozi tuljavo samo enkrat.DE-AS 28 35 794 also discloses an optical fiber device for measuring current strength using the Faraday effect, wherein the magnetic field surrounding the conductor through which the current flows influences the polarization state of the light passing through the path the optical fiber core enclosed by a conductor in the form of a winding. In contrast to DE - AS 22 61 151, this device, which does not have a reflecting surface at one end, already connects the light at one end and splits it at the other end, and the fiber coil must have double the number of threads so that it keeps the same angle as the polarization plane turns because light passes through the coil only once.
Iz te poznane naprave in iz prikaza “Magneto-optic current sensing with birefringent fibers” avtorjev S.C. Rashleigh in R. Ulrich, objavljenega v Appl. Phys. Lett. 34 (11) s 1.junija 1979 je dalje poznano, da se optično vlakno z zavrtenjem okoli svoje podolžne osi izpostavlja dvojnemu krožnemu lomu, s čimer bo v nadaljevanju opisani nedostatek, ki je nastal v v obliki tuljave navitem optičnem vlaknu, s tem kompenziran. Z neobhodnim zavrtenjem vlakna pri navijanju tuljave se bo prečni prerez vlakna deformiral eliptično, pri čemer je vlakno izpostavljeno znatnemu linearnemu dvojnemu lomu, ki zmajŠuje delovanje Faradayevega efekta in lahko v neugodnih primerih privede do tega, da Faradayev efekt ni več merljiv oziroma ne pomeni isto. Z vrtenjem vlakna, ki ga dosežemo z dvojnim lomom, dosežemo, da se skupno razpoložljivi linearni dvojni lom upošteva le kot motnja na skupno razpoložljivem krožnem dvojnem lomu, tako da na Faradayev efekt ne vpliva z nazivno vrednostjo, tako da je le-ta popolnoma učinkovit.From this known device and from the display of "Magneto-optic current sensing with birefringent fibers" by S.C. Rashleigh and R. Ulrich, published in Appl. Phys. Lett. 34 (11) of 1 June 1979, it is further known that by rotating the optical fiber about its longitudinal axis, it is exposed to a double circular fracture, thereby defining the disadvantage resulting from the coil of the coiled optical fiber, thereby compensating. The necessary twist of the fiber when winding the coil will cause the cross-section of the fiber to be elliptically deformed, leaving the fiber subject to a significant linear double refraction that impairs the Faraday effect and may, in unfavorable cases, cause the Faraday effect to no longer be measurable or equal. By twisting the fiber obtained by double refraction, it is achieved that the total available linear double refraction is only considered as a disturbance on the jointly available circular double refraction, so that the Faraday effect is not affected by the nominal value, so that it is fully effective .
Pokazalo se je, da so prisotne pri istočasnem upoštevanju naukov pojasnjenih v člankih, namreč pri napravi z optičnim vlaknom, pri kateri okoli podolžne osi navito optično vlakno obkroža prevodnik pod visokonapetostnim potencialom v obliki navitja in ki ima na enem koncu odbojno površino, prav tako na visokonapetostnem potencialu, na drugem koncu vlakna pa izvedemo spajanje in razdvajanje svetlobe, še nedopustno visoke merilne napake, ki znašajo v neugodnih primerih več kot 100 %.They have been shown to be present at the same time as the teachings explained in the articles, namely, an optical fiber device in which an optical fiber wound around a longitudinal axis is surrounded by a conductor under high voltage winding potential and which has a reflecting surface at one end as well. high-voltage potential, and at the other end of the fiber, the coupling and separation of light are carried out, which is still unacceptably high measurement errors, amounting to more than 100% in adverse cases.
Opis rešitve tehničnega problema.Description of solution to a technical problem.
Tehnični problem smo rešili na ta način, da smo z zavijanjem optičnega vlakna okoli podolžne osi na znani način, izpostavili le-tega krožnemu dvojnemu razdvajanju in da smo en konec optičnega vlakna z odbojno površino tako postavili v neposredno bližino drugega konca, da predstavlja celo optično vlakno popolnoma v sebe zaprto pot.The technical problem was solved by wrapping the optical fiber around the longitudinal axis in a known manner, exposing it to a circular double separation, and placing one end of the optical fiber with a reflecting surface in close proximity to the other end to represent even the optical the fiber is completely closed in itself.
Prednosti dosežene z izumom so v tem, da postane preko v sebi zaprte poti optičnega vlakna uporaben zakon o pretoku in se lahko izzovejo magnetna polja prevodnika, čigar tok je treba meriti, pri čemer sosednji prevodnik ne more izzvati takih obračanj polarizacijske ravnine svetlobe v optičnem vlaknu, ki bi vplivala na rezultate meritve.The advantages of the invention are that a flow law becomes applicable through a closed optical fiber path and magnetic fields of a conductor whose current is to be measured can be elicited, and the adjacent conductor cannot induce such rotations of the polarizing plane of light in the optical fiber that would affect the measurement results.
Izum bo pobliže objasnjen na osnovi izvedbenega primera prikazanega na sl. 1, ki shematsko prikazuje napravo v skladu z izumom.The invention will be explained in greater detail on the basis of the embodiment shown in FIG. 1 which schematically shows a device according to the invention.
Naprava z optičnim vlaknom za merjenje jakosti električnega toka je sestavljena iz optičnega vlakna 2 ovitega okoli njegove podolžne osi, ki sega z enim svojim koncem 6, pred katerim je leča 7, k prevodniku 1 pod visokonapetostnim potencialom, in to kot navitje 3 okrog prevodnika 1 z določenim številom drugega ob drugem navitih navojev in se ponovno vrača v bližino leče 7, pri čemer ima drugi konec 4 odbojno površino 5, ki je postavljena pod pravim kotom glede na podolžno os vlakna.An optical fiber device for measuring current strength consists of optical fiber 2 wrapped around its longitudinal axis, extending at one end 6, preceded by the lens 7, to conductor 1 at high voltage potential, as a winding 3 around conductor 1 with a certain number of side-by-side winding threads and returning again to the lens 7, the other end 4 having a reflecting surface 5 at right angles to the longitudinal axis of the fiber.
Leča 7 združuje skozi prizmo 8 prepuščeno, polarizirano svetlobo, ki jo izžareva laser 10, v en konec 6 optičnega vlakna 2. Prevodnik svetlobe je znotraj dela optičnega vlakna 2 oblikovanega v navitje 3 izpostavljen magnetnemu polju, ki nastane zaradi toka, ki teče skozi prevodnik 1. Na osnovi Faradayevega efekta se polarizira ravnina vodene svetlobe v času prehoda skozi navitje 3 in s tem se obrne tudi magnetno polje, pri čemer je velikost kota obračanja merilo za integral po poti jakosti magnetnega polja.The lens 7 combines, through prism 8, the transmitted, polarized light emitted by the laser 10 into one end 6 of the optical fiber 2. The light conductor is exposed to a magnetic field generated by the flow through the conductor through a part of the optical fiber 2 formed into the coil 3. 1. Based on the Faraday effect, the plane of guided light is polarized at the time of passage through the winding 3, thus also turning the magnetic field, the magnitude of the turning angle being a measure of the integral along the magnetic field path.
Za navitjem 3 svetloba prehaja dalje po optičnem vlaknu do njegovega drugega konca 4, kjer se odbija na površini 5, tako da je pot skozi optično vlakno 2 in skozi magnetno polje v področju navitja 3 v obratni smeri, pri čemer se polarizacijska ravnina ponovno obrne, tako da je kot obračanja polarizacijske ravnine pri prihodu svetlobe na lečo 7 glede na kot obračanja pri vstopu svetlobe na odbojno površino 5 skupaj podvojen.After coil 3, light passes further along the optical fiber to its other end 4, where it is reflected on the surface 5, so that the path is through the optical fiber 2 and through the magnetic field in the coil region 3 in the opposite direction, with the polarization plane reversed, so that the angle of rotation of the polarization plane when the light arrives at the lens 7 with respect to the angle of rotation at the light's entrance to the reflecting surface 5 is doubled together.
Združevanje in razdvajanje svetlobe se izvaja s pomočjo leče 7. Po razdvajanju pride svetloba iz optičnega vlakna 2 skozi prizmo 8 do naprave za vrednotenje, ki ima še eno prizmo, dva polarizatorja 11, 12 in dva fotodetektorja 13, 14, kjer določimo kot obračanja, kateremu je bila s prehodom skozi optično vlakno 2 izpostavljena polarizacijska ravnina svetlobe in ki je merilo za jakost električnega toka, ki teče v prevodniku 1.The combining and separation of light is accomplished by means of lens 7. After separation, light from optical fiber 2 passes through the prism 8 to the evaluation device having another prism, two polarizers 11, 12 and two photodetectors 13, 14, where the rotation angle is determined, to which a polarization plane of light has been exposed by passing through optical fiber 2 and which is a measure of the strength of the electric current flowing in conductor 1.
Merilne napake so zanemarljivo majhne, ker z zavijanjem optičnega vlakna 2 po eni strani odstranimo vpliv linearnega dvojnega loma, po drugi strani pa pri zaprti poti optičnega vlakna 2, magnetna polja prevodnika 1, čigar tok merimo, kot tudi drugih bližnjih prevodnikov ne morejo izzvati dodatnih obračanj polarizacijske ravnine svetlobe v optičnih vlaknih 2.Measurement errors are negligible, because by twisting optical fiber 2, on the one hand, the influence of linear double refraction is eliminated and, on the closed path of optical fiber 2, the magnetic fields of conductor 1 whose current is measured, as well as of other nearby conductors, cannot cause additional rotations of the polarization plane of light in optical fibers 2.
Za MWB MESSVVANDLER-BAU AG, Bamberg NemčijaFor MWB MESSVVANDLER-BAU AG, Bamberg Germany
Claims (1)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3923804A DE3923804A1 (en) | 1989-07-19 | 1989-07-19 | FIBER OPTICAL ARRANGEMENT FOR MEASURING THE STRENGTH OF AN ELECTRIC CURRENT |
| YU136290A YU47724B (en) | 1989-07-19 | 1990-07-12 | OPTICAL FIBER DEVICE FOR ELECTRICAL CURRENT MEASUREMENT |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| SI9011362A true SI9011362A (en) | 1998-08-31 |
| SI9011362B SI9011362B (en) | 1999-10-31 |
Family
ID=6385322
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| SI9011362A SI9011362B (en) | 1989-07-19 | 1990-07-12 | Fibre optic arrangement for measuring the strength of an electric current |
Country Status (14)
| Country | Link |
|---|---|
| EP (1) | EP0483189B1 (en) |
| CN (1) | CN1026159C (en) |
| AT (1) | ATE99063T1 (en) |
| AU (1) | AU5954790A (en) |
| BA (1) | BA97215A (en) |
| DD (1) | DD296751A5 (en) |
| DE (2) | DE3923804A1 (en) |
| DK (1) | DK0483189T3 (en) |
| ES (1) | ES2063972T3 (en) |
| SI (1) | SI9011362B (en) |
| TR (1) | TR26408A (en) |
| WO (1) | WO1991001501A1 (en) |
| YU (1) | YU47724B (en) |
| ZA (1) | ZA905606B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB9100924D0 (en) * | 1991-01-16 | 1991-02-27 | Rogers Alan J | Interference-free optical-fibre current measurement |
| DE4115370A1 (en) * | 1991-05-10 | 1992-11-26 | Asea Brown Boveri | Fibre=optic sensor for alternating electric fields or voltages - has piezoelectric element with attached optical fibre carrying two coherent light modes, and also fibre length variation detector |
| FR2686423B1 (en) * | 1992-01-22 | 1996-12-13 | Balteau France | POLARIMETRIC BOX FOR MEASURING THE ANGLE OF FARADAY. |
| DE4224190B4 (en) * | 1992-07-22 | 2007-01-18 | Abb Research Ltd. | Fiber optic current sensor |
| DE4311328A1 (en) * | 1993-04-06 | 1994-10-13 | Siemens Ag | Optical measuring arrangement for measuring an electrical current with intertwined transmission lines |
| DE4312183A1 (en) * | 1993-04-14 | 1994-10-20 | Siemens Ag | Optical measuring method for measuring an electrical alternating current with temperature compensation and device for carrying out the method |
| DE4312184A1 (en) * | 1993-04-14 | 1994-10-20 | Siemens Ag | Optical measuring method for measuring an electrical alternating current with temperature compensation and device for carrying out the method |
| KR100310373B1 (en) * | 1993-10-01 | 2001-12-15 | 칼 하인쯔 호르닝어 | Method and apparatus for measuring alternating current with temperature compensation |
| DE4432146A1 (en) * | 1994-09-09 | 1996-03-14 | Siemens Ag | Method and device for measuring an electrical alternating current with temperature compensation |
| DE4436181A1 (en) * | 1994-10-10 | 1996-04-11 | Siemens Ag | Method and device for measuring an electrical variable with temperature compensation by fitting |
| DE19608946A1 (en) * | 1996-03-08 | 1997-09-18 | Daimler Benz Ag | Fibre coil production method from light conductor fibres for magnetooptic current sensor |
| JP3488576B2 (en) | 1996-08-30 | 2004-01-19 | 株式会社東芝 | Optical current transformer |
| DE29711683U1 (en) * | 1997-07-03 | 1998-11-05 | Felten & Guilleaume Energie | Sensor arrangement |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3746983A (en) * | 1970-07-20 | 1973-07-17 | Transformatoren Union Ag | Apparatus fur measuring very high currents particularly direct currents |
| AU1440676A (en) * | 1975-06-05 | 1977-12-01 | Gen Electric Co Ltd | Magneto-optical transducers |
| DE2924804A1 (en) * | 1979-06-20 | 1981-01-15 | Licentia Gmbh | Prevention of temperature effects on fibre optic polarisation - has detector sensing changes in light polarisation caused by variation in tensional stress due to temperature |
| FR2461956A1 (en) * | 1979-07-24 | 1981-02-06 | Thomson Csf | INTERFEROMETRIC DEVICE FOR MEASURING ELECTRICAL CURRENT WITH OPTICAL FIBER |
| GB2104213A (en) * | 1981-08-12 | 1983-03-02 | Giers | Electric current measurement |
| DE3132414A1 (en) * | 1981-08-17 | 1983-02-24 | Ernst Dr. 5600 Wuppertal Brinkmeyer | Arrangement for separating backscattered light in systems having optical fibres |
| DE3363682D1 (en) * | 1982-03-12 | 1986-07-03 | Thomson Csf | Interferometric glass fibre current measuring device |
-
1989
- 1989-07-19 DE DE3923804A patent/DE3923804A1/en not_active Withdrawn
-
1990
- 1990-07-12 DK DK90910592.6T patent/DK0483189T3/en active
- 1990-07-12 AT AT90910592T patent/ATE99063T1/en not_active IP Right Cessation
- 1990-07-12 EP EP90910592A patent/EP0483189B1/en not_active Expired - Lifetime
- 1990-07-12 SI SI9011362A patent/SI9011362B/en not_active IP Right Cessation
- 1990-07-12 AU AU59547/90A patent/AU5954790A/en not_active Abandoned
- 1990-07-12 YU YU136290A patent/YU47724B/en unknown
- 1990-07-12 WO PCT/DE1990/000532 patent/WO1991001501A1/en active IP Right Grant
- 1990-07-12 ES ES90910592T patent/ES2063972T3/en not_active Expired - Lifetime
- 1990-07-12 DE DE90910592T patent/DE59003976D1/en not_active Expired - Fee Related
- 1990-07-17 TR TR90/0685A patent/TR26408A/en unknown
- 1990-07-17 ZA ZA905606A patent/ZA905606B/en unknown
- 1990-07-18 DD DD90342876A patent/DD296751A5/en not_active IP Right Cessation
- 1990-07-19 CN CN90104758A patent/CN1026159C/en not_active Expired - Fee Related
-
1997
- 1997-05-02 BA BA970215A patent/BA97215A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| CN1051427A (en) | 1991-05-15 |
| EP0483189B1 (en) | 1993-12-22 |
| SI9011362B (en) | 1999-10-31 |
| BA97215A (en) | 2001-09-14 |
| DE3923804A1 (en) | 1991-01-31 |
| EP0483189A1 (en) | 1992-05-06 |
| CN1026159C (en) | 1994-10-05 |
| ATE99063T1 (en) | 1994-01-15 |
| ZA905606B (en) | 1991-06-26 |
| YU47724B (en) | 1996-01-08 |
| DK0483189T3 (en) | 1994-01-31 |
| AU5954790A (en) | 1991-02-22 |
| WO1991001501A1 (en) | 1991-02-07 |
| DE59003976D1 (en) | 1994-02-03 |
| ES2063972T3 (en) | 1995-01-16 |
| YU136290A (en) | 1993-11-16 |
| DD296751A5 (en) | 1991-12-12 |
| TR26408A (en) | 1995-03-15 |
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| IF | Valid on the event date | ||
| KO00 | Lapse of patent |
Effective date: 20050412 |