CN102680763B - Photovoltage measuring device - Google Patents
Photovoltage measuring device Download PDFInfo
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- CN102680763B CN102680763B CN201210061663.5A CN201210061663A CN102680763B CN 102680763 B CN102680763 B CN 102680763B CN 201210061663 A CN201210061663 A CN 201210061663A CN 102680763 B CN102680763 B CN 102680763B
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Abstract
The present invention provides a photovoltage measuring device capable of stably raising quantity of light, and is characterized in that: a light emitted from a light source 2 driven by a light source driving device 1 passes through an SM coupler 12 and is guided to a position near a measuring point by utilizing a single mode fiber 13; the light is polarized linearly by utilizing a fiber type polarizer 14, and then is polarized elliptically by utilizing a fiber type 1/8 wavelength plate 15, after that, the light is collimated by utilizing a collimator 16, then passes through an electrooptical component 7, and is reflected by a reflecting film 17, then, the light passes through the electrooptical component again, and is coupled with the fiber type 1/8 wavelength plate 15 by utilizing the collimator 16. A guiding part of the fiber type polarizer 14 and an adhesion part of the fiber type 1/8 wavelength plate 15 are contained in a cylindrical hole 18a formed in a specified component 18 used for fixing, and a specified adhesive is filled between the guiding part of the fiber type polarizer and an inner wall of the cylindrical hole to form an adhesive layer 19, so as to fix the guiding part of the fiber type polarizer to the cylindrical hole.
Description
Technical field
The present invention relates to electric substation, generating power equipment and the photovoltage determinator that measures of the voltage of electric system.
Background technology
Usually, in photovoltage determinator, in order to carry out high-precision mensuration, need the light quantity making arrival detecting device to stablize.But, in the existing photovoltage determinator of optics needing a large amount of large-scale (bulk), because vibration, temperature variation thus coupling light quantity easily change in coupling (coupling) part by optical collimator, thus existence to bring the problem of appreciable error to photovoltage determinator.
Patent documentation 1: Japanese Unexamined Patent Application Publication 2002-536697 publication
Unit such as “ such as non-patent literature 1: Gao Bridge Shao large Deng mono-smooth Guide wave paths type Port Star ケ Le ス Electricity circle セ Application サ " Electricity Theory Vol.114-B, No1 (1994)
In order to solve problem as described above, trial LiNbO
3deng waveguide form sensor (non-patent literature 1).But, LiNbO
3temperature characterisitic large, the change of sensitivity based on temperature is large, and LiNbO
3be the material that piezoelectricity and pyroelectricity are large, therefore due to vibration, temperature variation and induce voltage, still can cause producing error.Therefore, use as the more undemanding electric-field sensor of accuracy requirement and part for practicality, but as such as requiring the voltage sensor of electric power use etc. of less than 1% precision, then precision is not enough, is not the technical merit can applied in present situation.
Therefore, it is desirable to develop a kind of photovoltage determinator, adopt that the such temperature characterisitic of BGO, BSO is comparatively good, piezoelectricity and the little crystal of pyroelectricity, more miniaturization and reducing portion number of packages, thus improve light quantity stability.
Summary of the invention
The present invention, for solving prior art problem as described above, its object is to provide one to make the stability-enhanced photovoltage determinator of light quantity.
In order to solve above-mentioned problem, the photovoltage determinator of embodiment, be the photovoltage determinator of reflection-type, it at least possesses: light source; Polarization optical system, is used for making the light of this light source to become the polarized condition of regulation; Electrooptic element, carries out the light phase modulation corresponding to the voltage applied; Catoptron, makes the light through above-mentioned electrooptic element reflect; Photometer, detects the light intensity in above-mentioned anti-She Mirror reflection and through certain axle of the transmitted light of above-mentioned electrooptic element; And light accepting part, the transmitted light through above-mentioned Photometer is detected, and above-mentioned applying voltage is detected; The feature of this photovoltage determinator is, to the polarizer using optical-fiber type at least partially of above-mentioned polarization optical system; This polarizer is accommodated in the cylinder hole be arranged in the component for fixing of regulation.
According to the photovoltage determinator with structure as described above, optical system is significantly simplified, and, by the polarizer utilizing component for fixing to fix optical-fiber type, thus the use of the polarizer of optical-fiber type becomes possibility, therefore, it is possible to provide one seldom to use large component, make the stability-enhanced photovoltage determinator of light quantity.
Accompanying drawing explanation
Fig. 1 is the figure of the structure of the photovoltage determinator representing the first embodiment, Fig. 1 (A) is one-piece construction figure, Fig. 1 (B) is the side view of the fiber end face part of collimating apparatus, and Fig. 1 (C) is the A-A ' cut-open view of Fig. 1 (B).
The side view of Fig. 2 to be the figure of other structure of the photovoltage determinator representing the first embodiment, Fig. 2 (A) be fiber end face part of collimating apparatus, Fig. 2 (B) is the A-A ' cut-open view of Fig. 2 (A).
Fig. 3 is the integrally-built figure of the photovoltage determinator representing the second embodiment.
Embodiment
Hereinafter, with reference to the accompanying drawings of the photovoltage determinator of embodiment.
[the first embodiment]
(1-1) structure
In the photovoltage determinator of present embodiment, as shown in Fig. 1 (A), be configured to, from the light transmission SM coupling mechanism (coupler) 12 of light source 2 outgoing driven by light source drive device 1, single-mode fiber (single mode fiber) 13 is utilized to be directed near measuring point.In addition, be configured to, this light utilizes the polarizer 14 of optical-fiber type that arrange in the front end of single-mode fiber 13, that be made up of polarization-maintaining fiber (polarizationmaintaining fiber) and becomes linear polarization, and then utilizes the polarizer of 1/8 wavelength plate 15, the i.e. optical-fiber type of optical-fiber type and become elliptical polarized light.
Utilize collimating apparatus 16 from the light of 1/8 wavelength plate 15 outgoing of this optical-fiber type and be collimated, through have employed BGO (Bi
12geO
20) etc. the electrooptic element (Pockels effect element) 7 of monocrystalline, and to be reflected by the reflectance coating 17 putting on electrooptic element, and again through electrooptic element 7, utilize collimating apparatus 16 and be coupled with 1/8 wavelength plate 15 of optical-fiber type.
In addition, from the light of above-mentioned 1/8 wavelength plate 15 outgoing, when polarizer 14 again through optical-fiber type, the only light of the single polarized component of outgoing.The light quantity of this light is changed by the ellipticity of elliptical polarized light according to utilizing above-mentioned electrooptic element 7, exports the light of the light quantity corresponding to determined voltage.Like this, the light being subject to intensity modulated based on voltage utilizes single-mode fiber 13 to be sent back to SM coupling mechanism 12 again, branches into towards the light of light source 2 and the light towards detecting device 10 at SM coupling mechanism 12.Wherein, the light towards detecting device is transformed to electric signal by detecting device 10, utilizes electronic circuit 11, based on the modulation rate of this electric signal, and the voltage of the determined object of computing.
In addition, from the polarized condition of the light of 1/8 wavelength plate 15 outgoing, under alive state not being executed to electrooptic element 7, come and go the phase differential being subject to 1/8 wavelength+1/8 wavelength=1/4 wavelength, so just in time become rotatory polarization.On the other hand, under the state that voltage is applied with to electrooptic element 7, apply phase differential further by electrooptic element 7, thus the elliptical polarized light that outgoing is corresponding to the voltage of applying.2 times when the phase differential applied by electrooptic element 7 is one way, by making reflection-type, thus the sensitivity of photovoltage determinator becomes about 2 times.
In addition, Fig. 1 (B), Fig. 1 (C) are the figure of the fiber end face part representing collimating apparatus 16.That is, in present embodiment, 1/8 wavelength plate 15 of adhering with guiding (lead) part of above-mentioned optical-fiber type polarizer 14 is such as incorporated in be made in the component for fixing 18 of drum.Above-mentioned component for fixing 18 is provided with the slightly large cylinder hole 18a of the diameter of the optical fiber that diameter adopts than 1/8 wavelength plate 15, in this cylinder hole 18a, is accommodated with the leader of above-mentioned optical-fiber type polarizer 14 and the adhesion part of 1/8 wavelength plate 15.
Further, between the leader and the inwall of above-mentioned cylinder hole 18a of above-mentioned optical-fiber type polarizer 14, form adhesive coating 19 by injecting the sticker of regulation, thus be configured to, the leader of optical-fiber type polarizer 14 can be made to be fixed on above-mentioned cylinder hole 18a.In addition, above-mentioned sticker is only supplied to the leader of optical-fiber type polarizer 14, does not put on 1/8 wavelength plate 15 to make it.
(1-2) act on
The present embodiment with structure as described above has following effect.That is, such as, as the polarizer of the optical-fiber type of present embodiment, the structure as shown in patent documentation 1, replace crystal and use the optical fiber with birefringence.But such optical fiber with birefringence is difficult to fix, although therefore attempted application in current sensor, be not applied to the example of voltage sensor.
That is, in fibre optic current sensor, even if with sensor welding and the position deviation slightly of polarizer, also impact can not be brought on error.But in the sensor using large-scale electrooptic element, if the position of the fiber end face of collimator segment is not fixed with micron accuracy, then the coupling efficiency of collimating apparatus changes and produces error, or is not coupled completely and does not form sensor.Therefore, need with the front end of micron accuracy fixed fiber, if but fixing fore-end, then produce birefringence because of fixing, there is the problem producing new error.
To this, in the present embodiment, by adopting the structure as shown in Fig. 1 (C), the birefringence produced because of fixing can be suppressed.Namely, in the present embodiment, in the cylinder hole 18a being located at above-mentioned component for fixing 18, receive the leader of above-mentioned optical-fiber type polarizer 14 and the adhesion part of 1/8 wavelength plate 15, between the leader and the inwall of above-mentioned cylinder hole 18a of above-mentioned optical-fiber type polarizer 14, inject the sticker of regulation, thus the leader of optical-fiber type polarizer 14 can be fixed on above-mentioned cylinder hole 18a.
In addition, in the cylinder hole 18a of component for fixing 18, by not making sticker put on above-mentioned 1/8 wavelength plate 15, thus do not apply, by the stress caused of adhering, higher temperature stability can be maintained to 1/8 wavelength plate 15.On the other hand, although the stress of adhesion can be applied to the leader of optical-fiber type polarizer 14, but because the leader of optical-fiber type polarizer 14 is made up of polarization-maintaining fiber, even if therefore apply by the stress caused of adhering, also can not apply higher birefringence in the degree maintaining polarization, and stress can not cause error.
In addition, about positional precision, cylinder hole 18a and optical fiber profile all easily obtain the structure of precision about 1 μm, as long as use them just can realize the location of micron accuracy.Further, when hope suppress the small characteristic variations of the fibre optic polarizer caused by stress and cause because of thermal expansion change in location, certain just passable with forming component for fixing as glass, the pottery material that like that thermal expansion is little.
(1-3) effect
Like this, according to the present embodiment, optical system is significantly simplified, and by utilizing component for fixing to be fixed by the polarizer of optical-fiber type, the use of the polarizer of optical-fiber type become possibility, therefore, it is possible to reduce the use of large component.In addition, by suppressing the angular deviation of optical element when vibrating, the change of light loss can be suppressed, therefore, it is possible to make the light light quantity stabilization of light-receiving device.As a result, can provide a kind of can not be vibrated impact and carry out the photovoltage determinator of high-precision mensuration all the time.
(1-4) variation of the first embodiment
Fig. 2 (A), Fig. 2 (B) are the figure of the variation representing above-mentioned first embodiment, 1/8 wavelength plate 15 is extended in order to prevent adhesive coating 19, from the side opening cut hole 20 of component for fixing 18, near the weld of fibre optic polarizer 14 and 1/8 wavelength plate 15, form space 20a.Although sticker has extension property such for the gap landfill be formed between the cylinder hole 18a of component for fixing 18 and optical fiber because of capillarity, but by arranging this space 20a, sticker can not to more depths expansion, can prevent sticker from expanding to 1/8 wavelength plate 15 part, therefore, it is possible to maintain higher temperature stability.In addition, shape and the size of above-mentioned space 20a are not particularly limited, and can form spherical space near the weld of fibre optic polarizer 14 and 1/8 wavelength plate 15.
[the second embodiment]
(2-1) structure
Fig. 3 is the figure of the structure of the photovoltage determinator representing the second embodiment, present embodiment illustrates the structure being particularly useful for following situation, to be the measuring point of the set voltage of electrooptic element and the position that arranges light source and electronic circuit carry out growing by optical fiber the situation that distance transmits away from needing to this situation.
Namely, in the present embodiment, be configured to, 1/8 wavelength plate 15 that adopt optical-fiber type same with the first embodiment, and adopt polarized wave separation coupler 21, thus can the light of major axis minor axis of ellipse of separated light, and be configured to, the light of orthogonal 2 polarized waves 1 pair of optical fiber 13,13 is transmitted.
In addition, although not shown, but 1/8 wavelength plate 15 of the optical-fiber type of present embodiment is also same with the first embodiment, be such as incorporated in be formed at the component for fixing making drum cylinder hole in.In addition, as single-mode fiber, according to the structure that 2 cores are paired, then 2 optical fiber are in same vibration condition, thus more preferred.
(2-2) act on
In the past, be known to following situation: single-mode fiber has the advantage can grown distance and transmit, and can produce the change of loss but then, and produce the variation of transmission light quantity, cause error because of vibration.If the transmitting range of optical fiber increases, the impact vibrated also becomes large, can not ignore this error.In order to prevent this error, known can by the light quantity single-mode fiber transmission of the major axis and minor axis both sides that return the ellipse of the light of 1/8 wavelength plate 15 from electrooptic element 7.If present embodiment make use of the light quantity increase of a side in the light of these two axles, the situation that the opposing party reduces.That is, by detecting device, make that the signal of anti-phase applying depends on the change in voltage of tested fixed point and vibration is depended in light quantity change that positive is applied, thus clearly can distinguish the impact of vibration, therefore in long distance transmits, also can realize high-precision mensuration.
The light of such employing diaxon and the impact of removing the vibration transmitting optical fiber is known technology, but in the photovoltage determinator of employing Large components in the past, in order to be separated the light of diaxon and adopt and be referred to as PBS (Polarizing Beam Splitter, polarization beam apparatus) Large components, therefore the coupling optical system of PBS and optical fiber becomes 2, when being applied with vibration to this part, diaxon produces respective light quantity variation.That is, although there is the structure of attempting specially to make vibration resistance but test section becomes the problem of not vibration resistance on the contrary.To this, in the photovoltage determinator of present embodiment, coupling optical system becomes 1, and diaxon becomes same light quantity variation, therefore, it is possible to remove the impact of vibration and realize high-precision voltage determination.
(2-3) effect
As mentioned above, in the past by under the mode that large component is formed, the difference of the coupling efficiency of 2 orthogonal polarized waves becomes error, but by adopting polarizer 15 and the polarized wave separation coupler 21 of optical-fiber type, thus the coupling of electrooptic element and optical fiber becomes 1, therefore, it is possible to avoid this problem, high-precision voltage determination can be realized.
Like this, according to the present embodiment, even when the measuring point of the voltage set by electrooptic element and position that light source and electronic circuit be set away from and need the long distance of optical fiber to transmit, also the change of light loss can be suppressed by suppressing the angular deviation of optical element when vibrating, therefore the light light quantity stabilization of light-receiving device can not only be made, because coupling optical system becomes 1 and diaxon becomes the variation of same light quantity, therefore can also remove the impact of vibration and realize high-precision voltage determination.
In addition, although the description of several embodiment, but these embodiments are pointed out as an example, and be not intended to limit scope of invention.These embodiments can be implemented with other various form, within a range not departing from the gist of the invention, can carry out various omission, replacement and change.These embodiments and distortion thereof are contained in scope of invention and purport, in the invention described in scope being also contained in claim equally and equivalent scope thereof.
Symbol description
1 ... light source drive device
2 ... light source
7 ... electrooptic element
10 ... detecting device
11 ... electronic circuit
12 ... SM coupling mechanism
13 ... single-mode fiber
14 ... the polarizer of optical-fiber type
15 ... 1/8 wavelength plate of optical-fiber type
16 ... collimating apparatus
17 ... reflectance coating
18 ... component for fixing
19 ... adhesive coating
20 ... cut hole
21 ... polarized wave separation coupler.
Claims (3)
1. a photovoltage determinator is the photovoltage determinator of reflection-type,
At least possess:
Light source;
Polarization optical system, is used for making the light of this light source to become the polarized condition of regulation;
Electrooptic element, carries out the light phase modulation corresponding to the voltage applied;
Catoptron, makes the light through above-mentioned electrooptic element reflect;
Photometer, detects the light intensity through above-mentioned catoptron reflection and through certain axle of the transmitted light of above-mentioned electrooptic element; And
Light accepting part, detects the transmitted light through above-mentioned Photometer, and detects above-mentioned applying voltage;
The feature of this photovoltage determinator is,
Above-mentioned polarization optical system possesses the polarizer of optical-fiber type and the polarizer of optical-fiber type that keep optical fiber to form by plane of polarization;
The leader of the polarizer of above-mentioned optical-fiber type and above-mentioned polarizer are fused and are accommodated in the cylinder hole of the component for fixing being arranged at regulation, only the adhesion of the leader of the polarizer of above-mentioned optical-fiber type are fixed on the inwall of above-mentioned cylinder hole.
2. photovoltage determinator as claimed in claim 1, is characterized in that,
The polarized wave separation coupler of optical-fiber type is used as above-mentioned Photometer, utilize this polarized wave separation coupler and be separated into 2 orthogonal axle polarisations, the transmission of signal is carried out with a pair single-mode fiber, by wherein 1 carry the optical fiber of light to share with from above-mentioned light source to above-mentioned electrooptic element, and there is the coupling mechanism of the optical-fiber type be separated with the light towards above-mentioned light accepting part by the light from above-mentioned light source.
3. photovoltage determinator as claimed in claim 1, is characterized in that,
Space is provided with near that be arranged at the cylinder hole of above-mentioned component for fixing, that above-mentioned polarizer and plane of polarization preserve optical fiber fusion point.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP053285/2011 | 2011-03-10 | ||
| JP2011053285A JP5858629B2 (en) | 2011-03-10 | 2011-03-10 | Photovoltage measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102680763A CN102680763A (en) | 2012-09-19 |
| CN102680763B true CN102680763B (en) | 2015-01-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210061663.5A Expired - Fee Related CN102680763B (en) | 2011-03-10 | 2012-03-09 | Photovoltage measuring device |
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| JP (1) | JP5858629B2 (en) |
| CN (1) | CN102680763B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103884901B (en) * | 2014-04-04 | 2016-06-08 | 哈尔滨理工大学 | A kind of high voltage measuring system based on FP voltage sensor and measuring method |
| CN109752579A (en) * | 2017-11-07 | 2019-05-14 | 许继集团有限公司 | A kind of novel all-fiber electronic current transformer and a kind of optical-fibre wave plate |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85203104U (en) * | 1985-07-30 | 1986-06-25 | 清华大学 | D.c. and a.c. optical fiber potential meter |
| CN1540355A (en) * | 2003-04-24 | 2004-10-27 | 伟 郭 | Reflection type 'Sage-qinke' interferometer type current transformer prepared from full optical fiber |
| CN1703811A (en) * | 2002-10-04 | 2005-11-30 | 瑞尼斯豪公司 | Frequency stabilized laser system comprising phase modulation of backscattered light |
| CN101504504A (en) * | 2008-02-04 | 2009-08-12 | 冲电气工业株式会社 | Optical modulator and optical signal generation apparatus |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4416298A1 (en) * | 1994-05-09 | 1995-11-16 | Abb Research Ltd | Method and device for optically determining a physical quantity |
| US5907403A (en) * | 1996-01-22 | 1999-05-25 | Lockheed Martin Corp. | Optical dual Fabry-Perot interferometric strain/temperature sensor, and system for separate reading thereof |
| US6122415A (en) * | 1998-09-30 | 2000-09-19 | Blake; James N. | In-line electro-optic voltage sensor |
| US6891622B2 (en) * | 1999-02-11 | 2005-05-10 | Kvh Industries, Inc. | Current sensor |
| JP2001033492A (en) * | 1999-07-19 | 2001-02-09 | Toshiba Corp | Optical application measuring apparatus |
| JP2002040290A (en) * | 2000-07-28 | 2002-02-06 | Nippon Telegr & Teleph Corp <Ntt> | Fiber array part and its manufacturing method |
| JP2005300422A (en) * | 2004-04-14 | 2005-10-27 | Toshiba Corp | Photocurrent detecting apparatus |
| JP5534653B2 (en) * | 2008-05-28 | 2014-07-02 | 株式会社東芝 | Photovoltage sensor |
-
2011
- 2011-03-10 JP JP2011053285A patent/JP5858629B2/en not_active Expired - Fee Related
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2012
- 2012-03-09 CN CN201210061663.5A patent/CN102680763B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN85203104U (en) * | 1985-07-30 | 1986-06-25 | 清华大学 | D.c. and a.c. optical fiber potential meter |
| CN1703811A (en) * | 2002-10-04 | 2005-11-30 | 瑞尼斯豪公司 | Frequency stabilized laser system comprising phase modulation of backscattered light |
| CN1540355A (en) * | 2003-04-24 | 2004-10-27 | 伟 郭 | Reflection type 'Sage-qinke' interferometer type current transformer prepared from full optical fiber |
| CN101504504A (en) * | 2008-02-04 | 2009-08-12 | 冲电气工业株式会社 | Optical modulator and optical signal generation apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102680763A (en) | 2012-09-19 |
| JP5858629B2 (en) | 2016-02-10 |
| JP2012189447A (en) | 2012-10-04 |
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