CN105548664B - A kind of optical current measuring device - Google Patents
A kind of optical current measuring device Download PDFInfo
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- CN105548664B CN105548664B CN201610109523.9A CN201610109523A CN105548664B CN 105548664 B CN105548664 B CN 105548664B CN 201610109523 A CN201610109523 A CN 201610109523A CN 105548664 B CN105548664 B CN 105548664B
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- solenoid
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/0092—Arrangements for measuring currents or voltages or for indicating presence or sign thereof measuring current only
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- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
The invention discloses a kind of optical current measuring devices, including sense head system, dynamic correcting system, photoelectricity demodulating system and optical fiber branch device；Sense head system includes one or more crystal light valve magnetic field sensors, one or more solenoids, P1 current terminal and P2 current terminal, the both ends of crystal light valve magnetic field sensor are connect by optical fiber with optical fiber branch device, dynamic correcting system is connected by the downlink optical interface of optical fiber and optical fiber branch device, photoelectricity demodulating system includes light source, photoelectricity demodulating unit and optical cable, and photoelectricity demodulating system is connect by optical cable with optical fiber branch device.Apparatus of the present invention eliminate the influence of the factors such as temperature, magnetic field, amplify primary current signal by solenoid, while passing through difference double photo paths, eliminate external magnetic field interference, the measurement accuracy for substantially increasing optical transformer, being capable of measuring minimum rated current is 0.5A, and class of accuracy is 0.2S grades.
Description
Technical field
The present invention relates to electrical equipment technical field more particularly to a kind of optical current measuring devices.
Background technique
Currently, oil-filled induction Current Mutual Inductance is widely used under high pressure and ultra-high pressure condition, in electric system
Device is limited to realizing the measurement of electric current by its measuring principle, and there is under insulation difficulty, fault current for this kind of current transformer
The shortcomings such as magnetic saturation.Therefore, people strive to find always a kind of novel current transformer, are based on Faraday magnetooptical effect
The optical current mutual inductor of principle is considered as a kind of New type of current measuring device with wide application prospect, it has insulation
It is simple and reliable, without magnetic saturation, without second open circuit is dangerous, anti-electromagnetic interference capability is strong, small in size, light-weight, installation and transportation are convenient
The advantages that, compared with traditional CT, there is considerable cost performance.Therefore, this field has become what the world was competitively studied at present
Hot spot has some experimental prototype hanging net operations, achieves preferable effect nearly ten years, but also expose temperature stability,
Some problems such as long-term running stability.Therefore, optical current mutual inductor system, each portion of careful selection are rationally designed
Part is particularly important to improving its performance.
Summary of the invention
In order to overcome the deficiencies of the prior art, the present invention is to provide a kind of, and the optics based on crystal light valve magnetic field sensor is electric
Flow measuring apparatus is calculated measurement by analysis magnetic field and generates magnetic field using the method induced magnetic field of Faraday magnetooptical effect
Electric current amplifies primary current signal by solenoid, while by difference double photo paths, eliminating external magnetic field interference, significantly
Improve the measurement accuracy of optical transformer.
In order to solve the technical problem in background technique, the present invention provides a kind of optical current measuring devices, including pass
Feel head system, dynamic correcting system, photoelectricity demodulating system and optical fiber branch device；
The sense head system includes one or more crystal light valve magnetic field sensors, one or more solenoids, P1 electricity
Stream terminal and P2 current terminal, the crystal light valve magnetic field sensor are fixed in the solenoid, and same with the solenoid
Axis setting, the length of the crystal light valve magnetic field sensor are less than the solenoidal length, the solenoid for one when institute
It states P1 current terminal and P2 current terminal is drawn by solenoid both ends or when the solenoid is multiple, between the solenoid
Be linked in sequence by plain conductor, first solenoid of sequential connection draws P1 current terminal, sequential connection the last one
Solenoid draws P2 current terminal, and the both ends of the crystal light valve magnetic field sensor pass through optical fiber and the optical fiber branch device downlink
Optical interface connection, the crystal light valve magnetic field sensor is identical as the solenoidal quantity and corresponds；
The dynamic correcting system is connect by optical fiber with the downlink optical interface of the optical fiber branch device, the dynamic calibration
System forms on the outside of crystal light valve magnetic field sensor for converting optical signal into electric current and refers to magnetic field, the crystal
Light valve magnetic field sensor is detected simultaneously by the tested magnetic field with reference to magnetic field and solenoid generation；
The photoelectricity demodulating system includes light source and photoelectricity demodulating unit, the photoelectricity demodulating system by optical cable with it is described
The connection of optical fiber branch device uplink optical interface, the light source issue the first constant optical signal, the second optical signal and third optical signal,
First optical signal and the second optical signal are transferred to the crystal light valve magnetic field sensor by the optical fiber branch device, described
Third optical signal is transferred to the dynamic correcting system by the optical fiber branch device, and the crystal light valve magnetic field sensor is felt
The magnetic field signal for the tested electric current answered passes the photoelectricity demodulating system back by optical fiber branch device, and the photoelectricity demodulating system will be anti-
The optical signal being fed back to is converted into electric signal, and is demodulated, and tested electric current is calculated.
Further, the multiple solenoid pours integrally in parallel.
Further, the dynamic correcting system includes photoelectric calibration device and reference coil, the photoelectric calibration device and institute
The downlink optical interface connection of optical fiber branch device is stated, the reference coil is placed in the solenoid.
Further, the reference coil is identical as the quantity of the crystal light valve magnetic field sensor and corresponds, institute
It states and is linked in sequence between reference coil by plain conductor.
Further, the wavelength of first optical signal is 1400-1600nm；The wavelength of second optical signal is
1350-1550nm；The wavelength of the third optical signal is 850-1050nm.
Specifically, first optical signal and the second optical signal set are at difference double light path.
Specifically, the light source is laser.
Further, the current data that the photoelectricity demodulating system is measured is with the packing of IEC61850 standard agreement format, hair
It send to junior's combining unit.
A kind of optical current measuring device of the invention, eliminates the influence of the factors such as temperature, magnetic field, is put by solenoid
Big primary current signal, while by difference double photo paths, external magnetic field interference is eliminated, optical transformer is substantially increased
Measurement accuracy, being capable of measuring minimum rated current is 0.5A, and class of accuracy is 0.2S grades, reaches international most advanced level.
Detailed description of the invention
It, below will be to required in embodiment or description of the prior art in order to illustrate more clearly of technical solution of the present invention
The attached drawing used is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, right
For those of ordinary skill in the art, without creative efforts, it can also be obtained according to these attached drawings
Its attached drawing.
Fig. 1 is a kind of structural schematic diagram of optical current measuring device of the present invention.
Wherein, appended drawing reference is corresponding in figure are as follows: 1- crystal light valve magnetic field sensor, 2- solenoid, 3-P1 current terminal, 4-
P2 current terminal, 5- photoelectric calibration device, 6- reference coil, 7- optical fiber branch device, 8- light source, 9- photoelectricity demodulating unit, 10- light
Cable.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art without creative labor it is obtained it is all its
His embodiment, shall fall within the protection scope of the present invention.
Embodiment 1:
The invention discloses a kind of optical current measuring devices, including sense head system, dynamic correcting system, photoelectricity to demodulate
System and optical fiber branch device 7；
The sense head system includes 1, solenoid 2 of a crystal light valve magnetic field sensor, P1 current terminal 3 and P2
Current terminal 4, the crystal light valve magnetic field sensor 1 are fixed in the solenoid 2, and are coaxially disposed with the solenoid 2,
The length of the crystal light valve magnetic field sensor 1 is less than the length of the solenoid 2, the solenoid 2 P1 when being one
Current terminal 3, P2 current terminal 4 are drawn by 2 both ends of solenoid, P1 current terminal 3 and P2 current terminal 4 access tested electric current,
The both ends of the crystal light valve magnetic field sensor 1 are connect by optical fiber with the 7 downlink optical interface of optical fiber branch device, the crystal
Light valve magnetic field sensor 1 is identical as the quantity of the solenoid 2 and corresponds；
The dynamic correcting system is connect by optical fiber with the downlink optical interface of the optical fiber branch device 7, the dynamic school
Positive system forms on the outside of crystal light valve magnetic field sensor 1 for converting optical signal into electric current and refers to magnetic field, the crystalline substance
Body light valve magnetic field sensor 1 is detected simultaneously by the tested magnetic field with reference to magnetic field and the generation of the solenoid 2；
The photoelectricity demodulating system includes light source 8 and photoelectricity demodulating unit 9, the photoelectricity demodulating system by optical cable 10 with
7 uplink optical interface of the optical fiber branch device connection, the light source 8 issue the first constant optical signal, the second optical signal and third
Optical signal, first optical signal and the second optical signal are transferred to the crystal light valve magnetic field by the optical fiber branch device 7 and pass
Sensor 1, the third optical signal are transferred to the dynamic correcting system, the crystal light valve magnetic by the optical fiber branch device 7
The magnetic field signal for the tested electric current that field sensor 1 is incuded passes the photoelectricity demodulating system, the light back by optical fiber branch device 7
It is electrolysed adjusting system and the optical signal fed back to is converted into electric signal, and demodulated, calculate tested electric current.
Further, the multiple solenoid 2 pours integral in parallel.
Further, the dynamic correcting system includes photoelectric calibration device 5 and reference coil 6, the photoelectric calibration device 6 with
The downlink optical interface of the optical fiber branch device 7 connects, and the reference coil 6 is placed in the solenoid 2.
Further, the reference coil 6 is identical as the quantity of the crystal light valve magnetic field sensor 1 and corresponds,
It is linked in sequence between the reference coil 6 by plain conductor.
Further, the wavelength of first optical signal is 1550nm, power is 450 μ W；The wave of second optical signal
A length of 1490nm, power are 450 μ W；The wavelength of the third optical signal is 980nm, power is 120 μ W.
Specifically, first optical signal and the second optical signal set are at difference double light path.
Specifically, the light source is laser.
Further, the current data that the photoelectricity demodulating system is measured is with the packing of IEC61850 standard agreement format, hair
It send to junior's combining unit.
Embodiment 2:
Referring to Fig. 1, the invention discloses a kind of optical current measuring device, including sense head system, dynamic calibration system
System, photoelectricity demodulating system and optical fiber branch device 7；
The sense head system includes two crystal light valve magnetic field sensors, 1, two solenoid 2, P1 current terminal 3 and P2
Current terminal 4, the crystal light valve magnetic field sensor 1 are fixed in the solenoid 2, and are coaxially disposed with the solenoid 2,
The length of the crystal light valve magnetic field sensor 1 is less than the length of the solenoid 2, the solenoid 2 spiral shell when being two
It is linked in sequence between spool 2 by plain conductor, first solenoid of sequential connection draws P1 current terminal 3, is linked in sequence
The last one solenoid draw P2 current terminal 4, P1 current terminal 3 and P2 current terminal 4 access tested electric current, the crystal
The both ends of light valve magnetic field sensor 1 are connect by optical fiber with the 7 downlink optical interface of optical fiber branch device, the crystal light valve magnetic field
Sensor 1 is identical as the quantity of the solenoid 2 and corresponds；
The dynamic correcting system is connect by optical fiber with the downlink optical interface of the optical fiber branch device 7, the dynamic school
Positive system forms on the outside of crystal light valve magnetic field sensor 1 for converting optical signal into electric current and refers to magnetic field, the crystalline substance
Body light valve magnetic field sensor 1 is detected simultaneously by the tested magnetic field with reference to magnetic field and the generation of the solenoid 2；
The photoelectricity demodulating system includes light source 8 and photoelectricity demodulating unit 9, the photoelectricity demodulating system by optical cable 10 with
7 uplink optical interface of the optical fiber branch device connection, the light source 8 issue the first constant optical signal, the second optical signal and third
Optical signal, first optical signal and the second optical signal are transferred to the crystal light valve magnetic field by the optical fiber branch device 7 and pass
Sensor 1, the third optical signal are transferred to the dynamic correcting system, the crystal light valve magnetic by the optical fiber branch device 7
The magnetic field signal for the tested electric current that field sensor 1 is incuded passes the photoelectricity demodulating system, the light back by optical fiber branch device 7
It is electrolysed adjusting system and the optical signal fed back to is converted into electric signal, and demodulated, calculate tested electric current.
Further, the multiple solenoid 2 pours integral in parallel.
Further, the dynamic correcting system includes photoelectric calibration device 5 and reference coil 6, the photoelectric calibration device 6 with
The downlink optical interface of the optical fiber branch device 7 connects, and the reference coil 6 is placed in the solenoid 2.
Further, the reference coil 6 is identical as the quantity of the crystal light valve magnetic field sensor 1 and corresponds,
It is linked in sequence between the reference coil 6 by plain conductor.
Further, the wavelength of first optical signal is 1550nm, power is 450 μ W；The wave of second optical signal
A length of 1490nm, power are 450 μ W；The wavelength of the third optical signal is 980nm, power is 120 μ W.
Specifically, first optical signal and the second optical signal set are at difference double light path.
Specifically, the light source is laser.
Further, the current data that the photoelectricity demodulating system is measured is with the packing of IEC61850 standard agreement format, hair
It send to junior's combining unit.
A kind of optical current measuring device of the invention, eliminates the influence of the factors such as temperature, magnetic field, is put by solenoid
Big primary current signal, while by difference double photo paths, external magnetic field interference is eliminated, optical transformer is substantially increased
Measurement accuracy, being capable of measuring minimum rated current is 0.5A, and class of accuracy is 0.2S grades, reaches international most advanced level.
The optical current measuring device course of work of the embodiment of the present invention is as follows: issuing constant first by light source laser
Optical signal and the second optical signal pass sequentially through optical cable, optical fiber branch device and optical fiber and are transferred to crystal light valve magnetic field sensor, crystal
The magnetic field signal for the tested electric current that light valve magnetic field sensor is incuded passes photoelectricity demodulating system back by optical fiber, by light source laser
It issues constant third optical signal and passes sequentially through optical cable, optical fiber branch device and optical fiber and be transferred to dynamic correcting system, dynamic calibration
System converts optical signal into electric current, and then is formed on the outside of crystal light valve magnetic field sensor and refer to magnetic field, crystal light valve magnetic field
Sensor is detected simultaneously by the tested magnetic field with reference to magnetic field and solenoid generation；Crystal light valve magnetic field sensor is incuded tested
The magnetic field signal of electric current passes the photoelectricity demodulating system back by optical fiber, and the photoelectricity demodulating system turns the optical signal fed back to
It changes electric signal into, and is demodulated, calculate tested electric current, and with the packing of IEC61850 standard agreement format, be sent to junior
Combining unit.
Solenoid quantity is not necessarily two in the specific embodiment of the invention 2, can be three, four or more.
The above is a preferred embodiment of the present invention, it should be noted that for those skilled in the art
For, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also considered as
Protection scope of the present invention.
Claims (5)
1. a kind of optical current measuring device, which is characterized in that including sense head system, dynamic correcting system, photoelectricity demodulation system
System and optical fiber branch device (7)；
The sense head system includes one or more crystal light valve magnetic field sensors (1), one or more solenoids (2), P1
Current terminal (3) and P2 current terminal (4), the crystal light valve magnetic field sensor (1) are fixed in the solenoid (2), and
It is coaxially disposed with the solenoid (2), the length of the crystal light valve magnetic field sensor (1) is less than the length of the solenoid (2)
Degree, when the solenoid (2) is one, the P1 current terminal (3) and P2 current terminal (4) are drawn by solenoid (2) both ends,
Or the solenoid (2) is when being multiple, and by plain conductor sequential connection between the solenoid (2), the first of sequential connection
A solenoid draws P1 current terminal (3), the last one solenoid of sequential connection draws P2 current terminal (4), the crystal
The both ends of light valve magnetic field sensor (1) are connect by optical fiber with the optical fiber branch device (7) downlink optical interface, the crystal light valve
Magnetic field sensor (1) is identical as the quantity of the solenoid (2) and corresponds；
The dynamic correcting system is connect by optical fiber with the downlink optical interface of the optical fiber branch device (7), the dynamic calibration
System forms on the outside of crystal light valve magnetic field sensor (1) for converting optical signal into electric current and refers to magnetic field, the crystalline substance
Body light valve magnetic field sensor (1) is detected simultaneously by the tested magnetic field with reference to magnetic field and the solenoid (2) generation；The dynamic school
Positive system includes photoelectric calibration device (5) and reference coil (6), under the photoelectric calibration device (6) and the optical fiber branch device (7)
The connection of row optical interface, the reference coil (6) are placed in the solenoid (2)；The reference coil (6) and the crystal light valve
The quantity of magnetic field sensor (1) is identical and corresponds, and is linked in sequence between the reference coil (6) by plain conductor；
The photoelectricity demodulating system includes light source (8) and photoelectricity demodulating unit (9), and the photoelectricity demodulating system passes through optical cable (10)
It is connect with the optical fiber branch device (7) uplink optical interface, the light source (8) issues the first constant optical signal, the second optical signal
With third optical signal, first optical signal and the second optical signal set are at difference double light path, first optical signal and the second light
Signal is transferred to the crystal light valve magnetic field sensor (1) by the optical fiber branch device (7), and the third optical signal passes through institute
It states optical fiber branch device (7) and is transferred to the dynamic correcting system, the tested electricity that the crystal light valve magnetic field sensor (1) is incuded
The magnetic field signal of stream passes the photoelectricity demodulating system back by optical fiber branch device (7), and the photoelectricity demodulating system will be fed back to
Optical signal is converted into electric signal, and is demodulated, and tested electric current is calculated.
2. a kind of optical current measuring device according to claim 1, which is characterized in that the multiple solenoid (2) is flat
Row pours integral.
3. a kind of optical current measuring device according to claim 1, which is characterized in that the wavelength of first optical signal
For 1400-1600nm；The wavelength of second optical signal is 1350-1550nm；The wavelength of the third optical signal is 850-
1050nm。
4. a kind of optical current measuring device according to claim 1 or 3, which is characterized in that the light source is laser.
5. a kind of optical current measuring device according to claim 1, which is characterized in that the photoelectricity demodulating system is measured
Current data with IEC61850 standard agreement format packing, be sent to junior's combining unit.
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| CN201610109523.9A CN105548664B (en) | 2016-02-25 | 2016-02-25 | A kind of optical current measuring device |
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Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106443690B (en) * | 2016-08-31 | 2023-11-24 | 北京创想智控科技有限公司 | Magnetic suspension optical scanning distance measuring device and method |
| CN112362945A (en) * | 2020-11-26 | 2021-02-12 | 湖南新海讯光电有限公司 | Optical current measuring device |
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| CN2752926Y (en) * | 2004-11-03 | 2006-01-18 | 郭志忠 | Optical current mutual inductor |
| CN101571556A (en) * | 2008-04-30 | 2009-11-04 | 上海新跃仪表厂 | Sagnac interferometer type all-fiber current transformator |
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