CN109298233A - A kind of alterating and direct current flow sensor - Google Patents
A kind of alterating and direct current flow sensor Download PDFInfo
- Publication number
- CN109298233A CN109298233A CN201811455120.5A CN201811455120A CN109298233A CN 109298233 A CN109298233 A CN 109298233A CN 201811455120 A CN201811455120 A CN 201811455120A CN 109298233 A CN109298233 A CN 109298233A
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- China
- Prior art keywords
- circuit
- alterating
- direct current
- current flow
- module
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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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
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
Abstract
The invention discloses a kind of alterating and direct current flow sensor, including magnetism gathering rings, magnetic field detection module is connected on the circumference of magnetism gathering rings；The output end of magnetism gathering rings is connect with the input terminal of magnetic field detection module；It further include circuit module, circuit module includes analog circuit and digital circuit；The output end of magnetic field detection module and the input terminal of analog circuit connect, and the output end of analog circuit and the input terminal of digital circuit connect；Magnetism gathering rings also have the first opening and closing part, and magnetism gathering rings realize open or close by the first opening and closing part.Alterating and direct current flow sensor of the invention can carry out live detection to power equipment, and can accurately detect the curent change of microampere order, and have versatility to AC and DC electric power equipment.
Description
Technical field
The present invention relates to current sensing techniques field more particularly to a kind of alterating and direct current flow sensors.
Background technique
Power equipment often remains latency because unpredictable accident occurs and lacks in manufacture, transport, maintenance process
It falls into, and then in the long-term operation of power equipment, such defect is damaged by voltage, electric current, mechanical force, environment is influenced and chemistry
Corrosiveness etc. may aggravate defect rank, form the defect for influencing power equipment safety operation, such as humidified insulation, insulation machine
The centralities defect such as tool damage, insulating inner bubble, porcelain crackle, this kind of defect it is fast-growth, thus have it is biggish
Risk.The presence of these defects seriously threatens the safe operation of electric system, in general, if can at the initial stage of sprouting
To find and eliminate such defect, so that it may avoid the further destruction of power equipment.
Currently, the anticipation for defect, mainly there is two kinds of technological means of off-line testing and live detection.Wherein, offline exhausted
The method of edge test, there are commonly insulation measurement, DC break down voltage test and DC current leakage test etc., live detection sides
Method is mainly the methods of shelf depreciation and earth current.The detection of electric current either off-line testing or live detection, are all one
A important indicator for reflecting state of insulation.But because of the sensor wire mode problem of its sensor, although off-line checking method
Detection is accurate but is not directly applicable live live detection, and it is existing can the current sensor of live detection its detection accuracy
The minimum level for only reaching milliampere grade, is not able to satisfy the early stage latency defect test demand of power equipment, and can not fit extensively
For AC and DC electric power equipment.
Summary of the invention
For overcome the deficiencies in the prior art, it is an object of the invention to: a kind of alterating and direct current flow sensor is provided, can
To carry out live detection to power equipment, and it can accurately detect the curent change of microampere order；It is used not only for detection and hands over
Power equipment is flowed, and can be used for detecting direct current power equipment.The purpose of the present invention adopts the following technical scheme that realization:
A kind of alterating and direct current flow sensor, it is characterised in that:
Including magnetism gathering rings, magnetic field detection module is connected on the circumference of the magnetism gathering rings；The output end of the magnetism gathering rings with
The input terminal of the magnetic field detection module connects；
It further include circuit module, the circuit module includes analog circuit and digital circuit；The magnetic field detection module
Output end is connect with the input terminal of the analog circuit, and the input terminal of the output end of the analog circuit and the digital circuit connects
It connects；
The magnetism gathering rings also have the first opening and closing part, and the magnetism gathering rings are realized by first opening and closing part and open or close
It closes.
It further, further include fixed module, the magnetism gathering rings and magnetic field detection module are encapsulated in the fixed module
Inside.
Further, the outside of the fixed module is equipped with the magnetic masking layer of single or multi-layer structure, the magnetic masking layer
Shield effectiveness be greater than 30dB.
Further, the fixed module is equipped with the second opening and closing part of fixed module described in open or close；The magnetic cup
Cover third opening and closing part of the layer equipped with magnetic masking layer described in open or close；Second opening and closing part, third opening and closing part and described the
One opening and closing part is correspondingly arranged.
Further, the side wall of the fixed module is equipped with first through hole, and the magnetic masking layer is equipped with outside in it
Second through-hole of wall, the first through hole are correspondingly arranged with second through-hole, and the output end of the magnetic field detection module is successively
It is connect by the first through hole and the second through-hole with the analog circuit.
Further, the analog circuit includes amplifying circuit and a variety of filter circuits, the magnetic field detection module
Output end is connect with the input terminal of the amplifying circuit, and the input terminal of the output end of the amplifying circuit and the filter circuit connects
It connects, the output end of the filter circuit is connect with the input terminal of the digital circuit.
Further, the circuit module is equipped with interface, the input of the output end of the digital circuit and the interface
End connection.
Further, the magnetism gathering rings are made using soft magnetic materials；The fixed module is made of insulating materials
It forms；The magnetic masking layer is made using metal material.
Further, the magnetic field detection module by Hall element, anisotropic magnetoresistance element, giant magnetoresistance element and
One or more compositions in tunnel magnetoresistance element.
Further, the magnetic conductivity of the soft magnetic materials is 104More than.
Compared with prior art, the beneficial effects of the present invention are:
1, signal after the low-intensity magnetic field amplification for generating microampere order electric current, is accessed magnetic field by setting magnetism gathering rings by the present invention
Detection module, magnetic field detection module is fixed modular electrical isolation and avoids interfering, while magnetic masking layer is to external magnetic interference
It is effectively shielded, and then signal passes through the circuit module connecting with magnetic field detection modular electrical and is output to display equipment, thus
Realize the state of insulation on-the-spot test to the high capacitances power equipment such as power cable, arrester, casing.
2, the present invention realizes the fixation of the spatial position of magnetism gathering rings and magnetic field detection module by setting fixed module；
Insulating materials also is set by the material of fixed module, so that magnetism gathering rings, magnetic field detection module and magnetic cup inside fixed module
It covers layer and forms effective electrical isolation, so that it is guaranteed that magnetic masking layer reliable ground, eliminating test short circuit may to testing crew
Caused by security risk.
3, the present invention can effectively shield external interference signals by setting magnetic masking layer, make signal detection it is more accurate,
Reliably.
4, in analog circuit of the invention have various filter circuits, can respectively the signal to alternating current and direct current into
Row filtering, filtered signal sends digital circuit to, then exports by interface and give display equipment, to realize to alternating current
With the detection of the microampere order electric current of direct current.
Detailed description of the invention
The structural schematic diagram of alterating and direct current flow sensor Fig. 1 of the invention；
Fig. 2 is the structural schematic diagram of ac and dc current sensor application of the invention in cable live detection；
Fig. 3 is amplifying circuit schematic diagram of the invention；
Fig. 4 is filter circuit schematic diagram of the invention；
Fig. 5 is digital circuit schematic diagram of the invention.
In figure: 1, magnetism gathering rings；2, magnetic field detection module；3, fixed module；4, magnetic masking layer；5, circuit module；6, interface；
7, analog circuit；8, digital circuit；9, power cable；10, it is grounded；11, equipment is shown.
Specific embodiment
In the following, being described further in conjunction with attached drawing and specific embodiment mode to the present invention, it should be noted that
Under the premise of not colliding, new reality can be formed between various embodiments described below or between each technical characteristic in any combination
Apply example.In addition to specified otherwise, employed in the present embodiment to material and equipment be commercially available.
Embodiment 1:
Referring to Fig. 1, a kind of alterating and direct current flow sensor, including magnetism gathering rings 1 is connected with magnetic field inspection on the circumference of magnetism gathering rings 1
Survey module 2；The output end of magnetism gathering rings 1 is connect with the input terminal of magnetic field detection module 2；Magnetism gathering rings 1 can effectively poly- magnetic, for can
The cyclic structure of folding, internal diameter can be adjusted according to the size of detected power equipment；
It further include circuit module 5, circuit module 5 includes analog circuit 7 and digital circuit 8；The output of magnetic field detection module 2
End is connect with the input terminal of analog circuit 7, and the output end of analog circuit 7 is connect with the input terminal of digital circuit 8；Analog circuit 7
The functions such as reference voltage, offset adjusting, multistage amplification, low-pass filtering can be achieved；Digital circuit 8 mainly realizes signal gain tune
Section, temperature compensation, linear compensation, data storage, the functions such as display and processing；The schematic diagram of digital circuit 8 is referring to Fig. 5；
Magnetism gathering rings 1 also have the first opening and closing part (not shown), and magnetism gathering rings 1 are realized by the first opening and closing part and open or close
It closes.
It further include fixed module 3, magnetism gathering rings 1 and magnetic field detection module 2 are encapsulated in the inside of fixed module 3.Stent
Block 3 can be realized the fixation of 2 spatial position of magnetism gathering rings 1 and magnetic field detection module, and with magnetic masking layer 4 formed it is effective electrically every
From.
The outside of fixed module 3 is equipped with the magnetic masking layer 4 of multilayered structure, and the shield effectiveness of magnetic masking layer 4 is greater than 30dB.Magnetic
Shielded layer 4 is the openable and closable cyclic structure for being centered around 3 outside of fixed module.Magnetic masking layer 4 and fixed module 3 are that activity connects
It connects.Magnetic masking layer 4 can shield the interference in the extraneous magnetic field DC/AC, can also shield earth's magnetic field, Hz noise magnetic field equimagnetic
?.
Fixed module 3 is equipped with the second opening and closing part (not shown) of open or close fixed module 3；Magnetic masking layer 4 is equipped with
The third opening and closing part (not shown) of open or close magnetic masking layer 4；Second opening and closing part, third opening and closing part and the first opening and closing part pair
It should be arranged.
Since magnetism gathering rings 1, fixed module 3, magnetic masking layer 4 are all made of openable and closable structure, it is thus possible to which realization is not removed
The original electrical connection of power equipment can detect power equipment.Magnetism gathering rings 1, fixed module 3, magnetic masking layer 4
Opening angle can be adjusted according to tested power equipment, and seamless in closure, to ensure magnetic leakage free.
The side wall of fixed module 3 is equipped with first through hole (not shown), and magnetic masking layer 4 is equipped with the through its outboard sidewalls
Two through-hole (not shown), first through hole are correspondingly arranged with the second through-hole, and the output end of magnetic field detection module 2 passes sequentially through first
Through-hole and the second through-hole are connect with analog circuit 7.
Analog circuit 7 includes amplifying circuit and a variety of filter circuits, the output end and amplifying circuit of magnetic field detection module 2
Input terminal connection, the input terminal of the output end of amplifying circuit and filter circuit connects, output end and the number electricity of filter circuit
The input terminal on road 8 connects.A variety of filter circuits can respectively be filtered the signal of alternating current and direct current.
The schematic diagram of amplifying circuit is referring to Fig. 3；The schematic diagram of filter circuit is referring to fig. 4.
The circuit module 5 is equipped with interface 6, the input terminal company of the output end of the digital circuit 8 and the interface 6
It connects.The interface 6 is connect with external display equipment 11, the input terminal of the output end of the interface 6 and the display equipment 11
Connection.
Magnetism gathering rings 1 are made using soft magnetic materials；Fixed module 3 is made using insulating materials；Magnetic masking layer 4 is adopted
It is made with metal material；The metal material for being fabricated to magnetic masking layer 4 needs to have certain rigidity.
Magnetic field detection module 2 is by Hall element, anisotropic magnetoresistance element, giant magnetoresistance element and tunnel magnetoresistance element
It constitutes.
The magnetic conductivity of soft magnetic materials is 104More than.
The workflow that alterating and direct current flow sensor of the invention tests running power cable 9 is as follows:
1, the fixed module 3 of alterating and direct current flow sensor of the invention, magnetic masking layer 4 are successively opened, is inserted in operation
Power cable 9 ground line 10 on, referring to fig. 2；
2, it is closed fixed module 3, it is ensured that magnetism gathering rings 1 are tightly closed, and are left no gaps；Magnetic masking layer 4 is reclosed, and makes electric power
The ground line 10 of cable 9 is located at the center of the alterating and direct current flow sensor of annular；
3, the interface 6 on circuit module 5 is connected to external display equipment 11, the electricity on the ground line 10 of power cable 9
After the raw weak magnetic field signal of miscarriage is amplified signal by magnetism gathering rings 1, output will to magnetic field detection module 2, magnetic field detection module 2
Signal output gives the circuit module 5 of its electrical connection, and signal is output in display equipment 11 through the interface 6 on circuit module 5,
Read the data in display equipment 11；
4, testing staff assesses the operating status of power cable 9.
Embodiment 2:
The outside of fixed module 3 is equipped with the magnetic masking layer 4 of single layer, and magnetic masking layer 4 is flexibly connected with fixed module 3.
Other are the same as embodiment 1.
Embodiment 3:
The outside of fixed module 3 is equipped with the magnetic masking layer 4 of multilayer, and magnetic masking layer 4 is fixedly connected with fixed module 3.
Other are the same as embodiment 1.
Embodiment 4:
The outside of fixed module 3 is equipped with the magnetic masking layer 4 of multilayer, and magnetic masking layer 4 is flexibly connected with fixed module 3.
Other are the same as embodiment 1.
Embodiment 5:
Magnetic field detection module 2 is made of Hall element and anisotropic magnetoresistance element.
Other are the same as embodiment 1.
Embodiment 6:
Magnetic field detection module 2 is made of Hall element, anisotropic magnetoresistance element, giant magnetoresistance element.
Other are the same as embodiment 1.
Embodiment 7:
Magnetic field detection module 2 is made of giant magnetoresistance element and tunnel magnetoresistance element.
Other are the same as embodiment 1.
Embodiment 8:
Magnetic field detection module 2 is made of anisotropic magnetoresistance element, giant magnetoresistance element and tunnel magnetoresistance element.
Other are the same as embodiment 1.
It should be noted that in the description of the present invention, term " first ", " second " etc. are used for description purposes only, without
It can be interpreted as indication or suggestion relative importance.
Above embodiment is merely a preferred embodiment of the present invention mode, cannot limit the model protected of the present invention with this
It encloses, the variation and replacement for any unsubstantiality that those skilled in the art is done on the basis of the present invention belong to the present invention
Range claimed.
Claims (10)
1. a kind of alterating and direct current flow sensor, it is characterised in that:
Including magnetism gathering rings, magnetic field detection module is connected on the circumference of the magnetism gathering rings；The output end of the magnetism gathering rings with it is described
The input terminal of magnetic field detection module connects；
It further include circuit module, the circuit module includes analog circuit and digital circuit；The output of the magnetic field detection module
End is connect with the input terminal of the analog circuit, and the output end of the analog circuit is connect with the input terminal of the digital circuit；
The magnetism gathering rings also have the first opening and closing part, and the magnetism gathering rings realize open or close by first opening and closing part.
2. alterating and direct current flow sensor according to claim 1, which is characterized in that it further include fixed module, the poly- magnetic
Ring and magnetic field detection module are encapsulated in the inside of the fixed module.
3. alterating and direct current flow sensor according to claim 2, which is characterized in that the outside of the fixed module is equipped with single
The shield effectiveness of the magnetic masking layer of layer or multilayered structure, the magnetic masking layer is greater than 30dB.
4. alterating and direct current flow sensor according to claim 3, which is characterized in that the fixed module, which is equipped with, to be opened or close
Close the second opening and closing part of the fixed module；The magnetic masking layer is equipped with the third folding of magnetic masking layer described in open or close
Portion；Second opening and closing part, third opening and closing part and first opening and closing part are correspondingly arranged.
5. alterating and direct current flow sensor according to claim 3, which is characterized in that the side wall of the fixed module is equipped with the
One through-hole, the magnetic masking layer are equipped with the second through-hole through its outboard sidewalls, the first through hole and second through-hole pair
It should be arranged, the output end of the magnetic field detection module passes sequentially through the first through hole and the second through-hole and the analog circuit connects
It connects.
6. alterating and direct current flow sensor according to claim 1, which is characterized in that the analog circuit includes amplifying circuit
It is connect with the output end of a variety of filter circuits, the magnetic field detection module with the input terminal of the amplifying circuit, the amplification
The output end of circuit is connect with the input terminal of the filter circuit, and the output end of the filter circuit is defeated with the digital circuit
Enter end connection.
7. alterating and direct current flow sensor according to claim 1, which is characterized in that the circuit module is equipped with interface,
The output end of the digital circuit is connect with the input terminal of the interface.
8. alterating and direct current flow sensor according to claim 3, which is characterized in that the magnetism gathering rings use soft magnetic materials system
It forms；The fixed module is made using insulating materials；The magnetic masking layer is made using metal material.
9. alterating and direct current flow sensor according to claim 1, which is characterized in that the magnetic field detection module is by Hall member
One or more compositions in part, anisotropic magnetoresistance element, giant magnetoresistance element and tunnel magnetoresistance element.
10. alterating and direct current flow sensor according to claim 8, which is characterized in that the magnetic conductivity of the soft magnetic materials is
104More than.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811455120.5A CN109298233A (en) | 2018-11-30 | 2018-11-30 | A kind of alterating and direct current flow sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811455120.5A CN109298233A (en) | 2018-11-30 | 2018-11-30 | A kind of alterating and direct current flow sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109298233A true CN109298233A (en) | 2019-02-01 |
Family
ID=65141883
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811455120.5A Pending CN109298233A (en) | 2018-11-30 | 2018-11-30 | A kind of alterating and direct current flow sensor |
Country Status (1)
| Country | Link |
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| CN (1) | CN109298233A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110007133A (en) * | 2019-04-16 | 2019-07-12 | 中国科学院上海应用物理研究所 | A kind of digital alternating current-direct current flow sensor and electric current detecting method |
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