CN202661524U - Hybrid grating online temperature measurement type all-fiber current transformer - Google Patents
Hybrid grating online temperature measurement type all-fiber current transformer Download PDFInfo
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- CN202661524U CN202661524U CN201220283747.9U CN201220283747U CN202661524U CN 202661524 U CN202661524 U CN 202661524U CN 201220283747 U CN201220283747 U CN 201220283747U CN 202661524 U CN202661524 U CN 202661524U
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Abstract
The utility model relates to a hybrid grating online temperature measurement type all-fiber current transformer, which comprises a current detection light path and a temperature detection light path. The current detection light path comprises a light source, a polarization-maintaining coupler, a phase modulator, a polarization beam combiner, a polarization-maintaining transmission fiber and a sensing head, which are sequentially connected. The temperature detection light path comprises the light source, the polarization-maintaining coupler, an optical circulator, a single mode transmission fiber and the sensing head, which are sequentially connected. The light source, the polarization-maintaining coupler and the sensing head are shared by the two light paths. The light paths also comprise a shared photoelectric conversion modulation-demodulation unit which is connected with the polarization-maintaining coupler and the optical circulator respectively. The temperature of the sensing head can be measured in real time, and a measurement result of the current transformer can be accurately and reliably corrected.
Description
Technical field
The utility model relates to a kind of equipment and detection method thereof of electric current in the conductor being measured with optical means, belongs to electric power and uses and technical field of optical fiber sensing.
Background technology
All-fiber current transformator is high-voltage great-current measurement mechanism of new generation, and it adopts has the fiber optic materials of natural good insulating performance as sensing and transfer element.Sensing unit does not have electronic circuit, does not need power supply, is a kind of passive current sensor.All-fiber current transformator is compared with the conventional current mutual inductor has following advantage: measure bandwidth; Dynamic range is large; Good insulation preformance; Cause the danger of high pressure without open circuit; Do not contain iron core, do not have ferromagnetic resonance, magnetic saturation and the caused hysteresis phenomenon of large inductance; Oil-containing does not have explosion danger; Be subjected to electromagnetic interference influence little; Volume is little, lightweight, simple in structure.
All-fiber current transformator is based on Ampere law and Faraday electromagnetic induction principle to the measurement of electric current.When sensor fibre is arranged in when the magnetic field that electric current passes through to form is arranged, according to the Faraday electromagnetic induction principle, current information can be transformed in the phase place of two bundle circularly polarized lights, produces the Faraday phase differential.When two bundle circularly polarized lights are transferred to the sensor fibre end, produce mirror-reflection, (the left-handed change dextrorotation of two-beam modes swap, it is left-handed that dextrorotation becomes) return along original optical path afterwards, the Faraday effect doubles because of nonreciprocity, and again converting the linearly polarized light of two bundle orthogonal modes at the quarter wave plate place, the place interferes at the polarizer.
Although all-fiber current transformator has the incomparable advantage of conventional current mutual inductor, but because quarter wave plate, optical fiber Verdet constant have temperature dependency in its light path, cause stability and the measuring accuracy of current detecting to be affected, this has limited the application of optical fiber type current mutual inductor to a great extent.
Summary of the invention
The purpose of this utility model provide a kind of temperature that can measure in real time sensing head to the measurement result of current transformer carry out accurately, reliable hybrid grating temperature measurement on-line type all-fiber current transformator and the electric current detecting method thereof of revising.
To achieve these goals, technical solution adopted in the utility model is: a kind of hybrid grating temperature measurement on-line type all-fiber current transformator, comprise current detecting light path and temperature detection light path, the current detecting light path comprises the light source that is linked in sequence, polarization-maintaining coupler, phase-modulator, polarization beam combiner, protect inclined to one side Transmission Fibers and sensing head, the temperature detection light path comprises the light source that is linked in sequence, polarization-maintaining coupler, optical circulator, single-mode transmission optical fiber and sensing head, described light source, polarization-maintaining coupler and sensing head are shared by two light paths, described two light paths also comprise shared opto-electronic conversion modem module, and described opto-electronic conversion modem module is connected with optical circulator with described polarization-maintaining coupler respectively.
The interference signal that the light of the light of forward transmission and reverse transfer occurs in phase-modulator in the described current detecting light path is used for the detection of current signal to be measured; Reflect the reflecting light that has with temperature information through fiber grating in the described temperature detection light path, be used for the online temperature compensation of current signal.
Described light source is the ASE light source.
Described phase-modulator is lithium niobate phase modulator.
Described sensing head comprises two sense lines, current sense circuit and temperature sensing circuit.Described current sense circuit is comprised of quarter wave plate, low-birefringence sensor fibre and faraday's catoptron of being arranged on low-birefringence sensor fibre end; Described temperature sensor line route forms with the single-mode fiber of fiber grating.Described two sense lines are annular, jointly are packaged in the quartz glass tube that is full of inert gas, and described quartz glass tube outside is coated with cushion, and the cushion outside is the sensing head skeleton; The same annular location of described sensing head skeleton, cushion and quartz glass tube is provided with opening, and the inclined to one side Transmission Fibers of described guarantor and single-mode transmission optical fiber are connected single-mode fiber with the quarter wave plate of current sense circuit respectively by described opening and are connected with the temperature sensing circuit; The annular sense line central authorities of described sensing head also are provided with the rod that confluxes.
Further, the opening part of described sensing head skeleton is provided with sealing rubber ring.
Described opto-electronic conversion modem module comprises detector, OCM module, modulation-demodulation circuit and conversion output interface; Described modulation-demodulation circuit comprises analog to digital converter, data processing unit and the digital to analog converter that is linked in sequence, described data processing unit also is connected with described conversion output interface, the interior analog compensation algorithm with the sensing head temperature influence of described data processing unit; Described detector one end is connected with polarization-maintaining coupler, and received current detects the interference signal that occurs in the phase-modulator in the light path, and the other end is connected with the analog to digital converter of modulation-demodulation circuit, and interference signal is carried out modulation and demodulation; Described OCM module one end is connected with optical circulator, and with the reflecting light of temperature information, the other end is connected with the data processing unit of modulation-demodulation circuit, and temperature information is carried out online compensation in the reception temperature detection light path; Described OCM module is made of spectro-grating, detector array and electronic processing unit, adopts dense wavelength division multiplexing DWDM technology that optical wavelength is changed and converts electric signal analysis and conversion output to.
Further, the working temperature of described sensing head is-40 ℃～+ 60 ℃.
A kind of electric current detecting method of hybrid grating temperature measurement on-line type all-fiber current transformator comprises the steps: that (1) carry out humid test to hybrid grating temperature measurement on-line type all-fiber current transformator, obtains the analog compensation algorithm; (2) the analog compensation algorithm is embedded the data processing unit of hybrid grating temperature measurement on-line type all-fiber current transformator; (3) use hybrid grating temperature measurement on-line type all-fiber current transformator electric current to be measured to be detected the output detections result.
Described analog compensation algorithm obtains by the following method: (1) puts into temperature test chamber with the sensing head of hybrid grating temperature measurement on-line type all-fiber current transformator, regulates in the rod that confluxes electric current to reference current; (2) temperature of adjustment temperature test chamber, the current data of record temperature value and collection output behind the sensing head temperature stabilization; (3) temperature that makes temperature test chamber records the output current data of each temperature spot to rise on certain temperature interval by step (2); (4) temperature-current data that test is obtained is carried out modeling, according to the models fitting backoff algorithm, and backoff algorithm is revised, and obtains the analog compensation algorithm.
Further, described data processing unit is the FPGA control chip.
Further, the temperature range of described temperature test chamber is adjusted into-40 ℃～+ 60 ℃, and described temperature interval is adjusted into 10 ℃.
The beneficial effects of the utility model are: 1) proposed a kind of new approaches that solve optical fiber current mutual inductor temperature effect problem; 2) sensing head has made up electric current and two kinds of physical parameter parallel measurements of two light paths realizations of temperature; 3) realized that the all-fiber current transformator online compensation has solved its engineering and used the major limitation problem; 4) light path design has farthest reduced cost, two public light sources of light path; 5) the system temperature compensation need not electric power field test, need not the secondary debugging behind the system balance, and directly on-the-spot the installation uses manpower and material resources sparingly.
Description of drawings
Fig. 1 is the structural representation of the hybrid grating temperature measurement on-line of the utility model type all-fiber current transformator.
Fig. 2 is sensing head inner structure synoptic diagram of the present utility model.
Fig. 3 is the utility model opto-electronic conversion modem module structural representation.
Fig. 4 is OCM module fundamental diagram.
Fig. 5 is the modulation-demodulation circuit fundamental diagram.
Fig. 6 is Temperature Modeling test synoptic diagram.
Fig. 7 is effect contrast figure before and after the temperature compensation.
Among the figure,
Embodiment
Below in conjunction with accompanying drawing a kind of embodiment of the present utility model is made brief description.
Such as Fig. 1, a kind of hybrid grating temperature measurement on-line type all-fiber current transformator, comprise current detecting light path and temperature detection light path, the current detecting light path comprises the light source 1 that is linked in sequence, polarization-maintaining coupler 2, phase-modulator 3, polarization beam combiner 4, protect inclined to one side Transmission Fibers 5 and sensing head 6, the temperature detection light path comprises the light source 1 that is linked in sequence, polarization-maintaining coupler 2, optical circulator 7, single-mode transmission optical fiber 8 and sensing head 6, described light source 1, polarization-maintaining coupler 2 and sensing head 6 are shared by two light paths, described two light paths also comprise shared opto-electronic conversion modem module 9, and described opto-electronic conversion modem module 9 is connected with ring of light shape 7 devices with described polarization-maintaining coupler 2 respectively.
In the present embodiment, described light source 1 is the ASE light source.
Wherein, such as Fig. 1 and 2, described sensing head 6 comprises two sense lines, current sense circuit and temperature sensing circuit.Described current sense circuit is comprised of quarter wave plate 611, low-birefringence sensor fibre 612 and faraday's catoptron 613 of being arranged on low-birefringence sensor fibre 612 ends; Described temperature sensor line route forms with the single-mode fiber 621 of fiber grating 622.Described two sense lines are annular, jointly are packaged in the quartz glass tube 64 that is full of inert gas 63, and described quartz glass tube 64 outsides are coated with cushion 65, and cushion 65 outsides are sensing head skeleton 66; The same annular location of described sensing head skeleton 66, cushion 65 and quartz glass tube 64 is provided with opening 67, and the inclined to one side Transmission Fibers 5 of described guarantor is connected with single-mode transmission optical fiber and is connected single-mode fiber 621 with the temperature sensing circuit with the quarter wave plate 611 of current sense circuit respectively by described opening 67 and is connected; The annular sense line central authorities of described sensing head 6 also are provided with the rod 68 that confluxes.Further, described sensing skull, 66 opening 67 places are provided with sealing rubber ring 69.
Such as Fig. 3, described opto-electronic conversion modem module 9 comprises detector 91, OCM module 92, modulation-demodulation circuit 93 and conversion output interface 94; Wherein, such as Fig. 5, described modulation-demodulation circuit 93 comprises analog to digital converter 931, data processing unit 932 and the digital to analog converter 933 that is linked in sequence, described data processing unit 932 also is connected with described conversion output interface 94, described data processing unit 932 interior analog compensation algorithms with sensing head 6 temperature influences; Described detector 91 1 ends are connected with polarization-maintaining coupler 2, and received current detects the interference signal of phase-modulator 3 interior generations in the light path, and the other end is connected with the analog to digital converter 931 of modulation-demodulation circuit 93, and interference signal is carried out modulation and demodulation; Described OCM module 92 1 ends are connected with optical circulator 2, and with the reflecting light of temperature information, the other end is connected with the data processing unit 932 of modulation-demodulation circuit 93, and temperature information is carried out online compensation in the reception temperature detection light path; Such as Fig. 4, described OCM module 92 is made of spectro-grating 921, detector array 922 and electronic processing unit 923, adopts dense wavelength division multiplexing DWDM technology that optical wavelength is changed and converts electric signal analysis and conversion output to.
Method of work of the present utility model is as follows: ASE light source 1 produces a wide range light beam, and 2 beam splitting are two-beam through polarization-maintaining coupler, and the light beam signal enters phase-modulator 3 and uses as current sense, and other light beam enters optical circulator 7 and uses as temperature sensing.The light that enters phase-modulator 3 is transformed into linearly polarized light and is divided into two, the modulation signal modulation that the modulated line 95 of light phase applies, after the modulation two bundle output light enters respectively two input ends of polarization beam combiner 4, polarization divides bundling device 4 two bunch polarized lights to be merged on two optical axises of same output optical fibre quadrature, light beam after the merging is transferred to optical fiber sensor head 6 parts through the transmission polarization maintaining optical fibre 5 of certain distance, the quarter wave plate 611 that closes two polarization signal photocurrent sense lines of bundle is converted into respectively left circularly polarized light and right-circularly polarized light, then enter low-birefringence sensor fibre 612 and arrive faraday's catoptron 613, reflect to reverse transfer through two bundle rotatory polarization light after faraday's mirror reflects, this moment, the polarization state of two-beam exchanged at reflex time, be that former left circularly polarized light becomes right-circularly polarized light, former right-circularly polarized light becomes left circularly polarized light.Polarization signal is twice process low-birefringence sensor fibre 612 back and forth, when having electric current to pass through in the fluid confluence 68, can be transformed into according to Faradic electricity magnetic induction principle current information in the phase place of two bundle polarized lights, because Faraday effect has nonreciprocity so induced signal can double.The two bundle polarized lights that are loaded with current information turn back to the linearly polarized light that quarter wave plate 611 can be converted to again two bundle quadratures again again, divide bundling device 4 that the linearly polarized light of two bundle quadratures is injected into respectively in two optical fiber through polarization, light oppositely enters phase-modulator 3 and interferes, the detector 91 that interference signal is input to opto-electronic conversion modem module 9 receives, be converted to electric signal, data processing unit 932 through modulation-demodulation circuit 93 calculates output feedback signal, is applied to phase-modulator 3 through modulation lines 95.Enter the light signal of optical circulator 7 forwards transmission through the fiber grating 622 in the single-mode transmission optical fiber 8 arrival sensing heads 6, the optical wavelength of fiber grating 622 reflections is relevant with the residing temperature of grating, the light signal that is loaded with temperature information that fiber grating reflects oppositely turns back to optical circulator 7 through single-mode transmission optical fiber 8, the signal that optical circulator 7 will oppositely be passed back outputs to the OCM module 92 of opto-electronic conversion modem module 9, the spectro-grating 921 of OCM module 92 at first carries out incident light spectral resolution (space), detector array 922 receives the light signal after decomposing and it is carried out opto-electronic conversion, and the electric signal analysis after electronic processing unit 923 further will change also conversion is exported.Electric signal through electronic processing unit 923 conversion outputs is sent into modulation-demodulation circuit 93, and the data processing unit 932 of modulation-demodulation circuit 93 is embedded with the analog compensation algorithm, is exported by conversion output interface 94 after according to algorithm temperature information being compensated.
Such as Fig. 6, described analog compensation algorithm obtains by the following method: (1) puts into temperature test chamber 101 with the sensor 6 of hybrid grating temperature measurement on-line type all-fiber current transformator, regulates in the rod 68 that confluxes electric current to reference current; (2) temperature of adjustment temperature test chamber 101 records temperature value and gathers the current data of exporting by data acquisition system (DAS) 103 behind the sensing head temperature stabilization; (3) temperature that makes temperature test chamber 101 records the output current data of each temperature spot to rise on certain temperature interval by step (2); (4) temperature-current data that test is obtained is carried out modeling, according to the models fitting backoff algorithm, and backoff algorithm is revised, and obtains the analog compensation algorithm.
Wherein, comprehensive demodulating system 102 is the part of the hybrid grating temperature measurement on-line of the utility model type all-fiber current transformator except sensing head shown in Fig. 6.
The scope of analog compensation algorithm collecting temperature information is-40 ℃～+ 60 ℃ in the present embodiment, and a data acquisition is carried out at 10 ℃ at every interval, the temperature-current data that obtains is carried out modeling after, resulting compensation effect is as shown in Figure 7.Wherein, normalization constant multiplier SF is the measured value of electric current and the ratio of actual value.
In the present embodiment, described data processing unit is the FPGA control chip.
More than an example of the present utility model is had been described in detail, but described content only is preferred embodiment of the present utility model, can not be considered to be used to limiting practical range of the present utility model.All equalizations of doing according to the utility model application range change and improve etc., all should still belong within the patent covering scope of the present utility model.
Claims (7)
1. a hybrid grating temperature measurement on-line type all-fiber current transformator is characterized in that: comprise current detecting light path and temperature detection light path; Described current detecting light path comprises the inclined to one side Transmission Fibers of light source, polarization-maintaining coupler, phase-modulator, polarization beam combiner, guarantor and the sensing head that is linked in sequence; Described temperature detection light path comprises light source, polarization-maintaining coupler, optical circulator, single-mode transmission optical fiber and the sensing head that is linked in sequence; Described light source, polarization-maintaining coupler and sensing head are shared by two light paths; Described two light paths also comprise shared opto-electronic conversion modem module, and described opto-electronic conversion modem module is connected with optical circulator with described polarization-maintaining coupler respectively;
The interference signal that the light of the light of forward transmission and reverse transfer occurs in phase-modulator in the described current detecting light path is used for the detection of current signal to be measured; Reflect the reflecting light that has with temperature information through fiber grating in the described temperature detection light path, be used for the online temperature compensation of current signal.
2. hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 1, it is characterized in that: described sensing head comprises two sense lines, current sense circuit and temperature sensing circuit; Described current sense circuit is comprised of quarter wave plate, low-birefringence sensor fibre and faraday's catoptron of being arranged on low-birefringence sensor fibre end; Described temperature sensor line route forms with the single-mode fiber of fiber grating; Described two sense lines are annular, jointly are packaged in the quartz glass tube that is full of inert gas, and described quartz glass tube outside is coated with cushion, and the cushion outside is the sensing head skeleton; The same annular location of described sensing head skeleton, cushion and quartz glass tube is provided with opening, and the inclined to one side Transmission Fibers of described guarantor and single-mode transmission optical fiber are connected single-mode fiber with the quarter wave plate of current sense circuit respectively by described opening and are connected with the temperature sensing circuit; The opening part of described sensing head skeleton is provided with sealing rubber ring; The annular sense line central authorities of described sensing head also are provided with the rod that confluxes.
3. hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 1, it is characterized in that: described opto-electronic conversion modem module comprises detector, OCM module, modulation-demodulation circuit and conversion output interface;
Described modulation-demodulation circuit comprises analog to digital converter, data processing unit and the digital to analog converter that is linked in sequence, described data processing unit also is connected with described conversion output interface, the interior analog compensation algorithm with the sensing head temperature influence of described data processing unit;
Described detector one end is connected with polarization-maintaining coupler, and received current detects the interference signal that occurs in the phase-modulator in the light path, and the other end is connected with the analog to digital converter of modulation-demodulation circuit, and interference signal is carried out modulation and demodulation;
Described OCM module one end is connected with optical circulator, and with the reflecting light of temperature information, the other end is connected with the data processing unit of modulation-demodulation circuit, and temperature information is carried out online compensation in the reception temperature detection light path; Described OCM module is made of spectro-grating, detector array and electronic processing unit, adopts dense wavelength division multiplexing DWDM technology that optical wavelength is changed and converts electric signal analysis and conversion output to.
4. each described hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 1-3, it is characterized in that: described light source is the ASE light source.
5. each described hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 1-3, it is characterized in that: described phase-modulator is lithium niobate phase modulator.
6. hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 3, it is characterized in that: described data processing unit is the FPGA control chip.
7. each described hybrid grating temperature measurement on-line type all-fiber current transformator according to claim 1-3, it is characterized in that: the working temperature of described sensing head is-40 ℃ ~+60 ℃.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201220283747.9U CN202661524U (en) | 2012-06-15 | 2012-06-15 | Hybrid grating online temperature measurement type all-fiber current transformer |
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| CN201220283747.9U CN202661524U (en) | 2012-06-15 | 2012-06-15 | Hybrid grating online temperature measurement type all-fiber current transformer |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721847A (en) * | 2012-06-15 | 2012-10-10 | 天津光拓科技有限公司 | Hybrid grating on-line temperature measurement type all-fiber current transformer and current detection method thereof |
| CN106197741A (en) * | 2016-07-14 | 2016-12-07 | 盐城工学院 | Temperature-detecting device based on micro-nano long-period fiber grating sensor and method |
| CN108287262A (en) * | 2018-01-10 | 2018-07-17 | 武汉理工大学 | All-fiber current transformator temperature and vibrational feedback compensation system and measurement method |
-
2012
- 2012-06-15 CN CN201220283747.9U patent/CN202661524U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721847A (en) * | 2012-06-15 | 2012-10-10 | 天津光拓科技有限公司 | Hybrid grating on-line temperature measurement type all-fiber current transformer and current detection method thereof |
| CN102721847B (en) * | 2012-06-15 | 2014-12-10 | 天津光拓科技有限公司 | Hybrid grating on-line temperature measurement type all-fiber current transformer and current detection method thereof |
| CN106197741A (en) * | 2016-07-14 | 2016-12-07 | 盐城工学院 | Temperature-detecting device based on micro-nano long-period fiber grating sensor and method |
| CN106197741B (en) * | 2016-07-14 | 2018-08-28 | 盐城工学院 | Temperature-detecting device based on micro-nano long-period fiber grating sensor and method |
| CN108287262A (en) * | 2018-01-10 | 2018-07-17 | 武汉理工大学 | All-fiber current transformator temperature and vibrational feedback compensation system and measurement method |
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