CN105301549B - A kind of method and system for testing current transformer magnetic screen using three-dimensional magnetic field - Google Patents
A kind of method and system for testing current transformer magnetic screen using three-dimensional magnetic field Download PDFInfo
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- CN105301549B CN105301549B CN201510833065.9A CN201510833065A CN105301549B CN 105301549 B CN105301549 B CN 105301549B CN 201510833065 A CN201510833065 A CN 201510833065A CN 105301549 B CN105301549 B CN 105301549B
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Abstract
The invention belongs to electric device maintenances and applied technical field, and in particular to a kind of method and system for testing current transformer magnetic screen using three-dimensional magnetic field, the present invention apply electric current I by excitation sourcex、IyAnd IzThree groups of Exciting Windings for Transverse Differential Protection for respectively enteing magnetic field generator generate three quadrature fields Form the space spherical surface magnetic field H of different radii, each azimuth scan, while inductive signal caused by the secondary winding of measurement current transform er or current sensor are carried out to current transformer or current sensor, and the Magnetic Shielding Effectiveness of current transformer or current sensor is calculated.The test method of the present invention is chosen to the shielding material of current transformer or current sensor and the design of structure provides foundation, has guiding significance to electric energy meter interior layout and quality control, achievees the purpose that improve electric energy meter metering accuracy.
Description
Technical field
The invention belongs to space magnetic field detection technique fields, and in particular to a kind of to test current transformer using three-dimensional magnetic field
The method and system of magnetic screen.
Background technology
Electric energy meter is that universal electric measuring instrument is used in electric power enterprise, is《Measurement Law》Defined compulsory verification trade settlement
Measurement instrument.International Legal Organization (OIML) formulates R46, and to electric energy meter antimagnetic shield, more stringent requirements are proposed, rule
Determine influence of the interference to electric energy error of 400A/m power frequency magnetic field no more than a certain range, important component Current Mutual Inductance in electric energy meter
Device (current sensor) is more sensitive to alternating magnetic field, will produce large error under the interference of external magnetic field.Therefore, electric current is improved
Mutual inductor (current sensor) is especially heavy to the shield effectiveness of alternating magnetic field.When measuring Magnetic Shielding Effectiveness at this stage, mostly use greatly
Single direction magnetic field sources do not have gyromagnet characteristic, cannot simulate spherical surface magnetic field sources, and need to manually change direction could realize to shielding
The test in each orientation of box cannot fast and accurately measure its shield effectiveness, need to expend a large amount of human cost and be added larger
Human error.
There has been no measure three-dimensional rotation magnetic field application in current transformer (current sensor) magnetic screen efficiency at present.It fills out
Mend the domestic quickly multi-faceted blank for measuring magnetic field shielding efficiency accurate to mutual inductor progress.Meanwhile directly measuring mutual inductor two
The induced voltage of secondary winding is easily realized come the method for assessing its Magnetic Shielding Effectiveness and has very strong practicability.This method is to electricity
The shape and structure design of current transformer have guiding effect.Foundation is provided for electric energy meter interior layout and quality control.
It is to be understood that quadrature field of the three-dimensional rotation magnetic field by three directionsTo form space
Rotating excitation field, as shown in Figure 1, wherein space magnetic field vectorMeet：
In formulaWithRespectively represent the magnetic vector along X, Y, Z axis.
At the same time it can also change frequency, the phase of space magnetic field by the frequency for changing each group coil current, phase and amplitude
Position, amplitude, direction generate the spherical surface magnetic field sources of different radii, as shown in Fig. 2, along the magnetic field H of a certain axis direction of X, Y, Zi,
In：
Hi=μr×N×Ii,
In formula, μrFor relative permeability；N is coil turn, IiTo generate the corresponding exciting current in X, Y, Z axis magnetic field.
Invention content
The purpose of the present invention is to solve the above problem of the prior art, and the present invention provides a kind of electric using three-dimensional magnetic field test
The method and system of current transformer magnetic screen, the present invention chooses for shielding material and the design of structure provides foundation, for reality
Existing above-mentioned purpose, the technical solution adopted by the present invention are as follows：
A method of testing current transformer magnetic screen using three-dimensional magnetic field, it is characterised in that：Apply electricity by outside
Flow Ix、IyAnd IzThree groups of Exciting Windings for Transverse Differential Protection for respectively enteing magnetic field generator generate three quadrature fields WithIt is formed different
The space spherical surface magnetic field H of radius carries out each azimuth scan to current transformer, while measurement current transform er secondary winding is produced
Raw inductive signal, and the Magnetic Shielding Effectiveness of current transformer is calculated.
Preferably, the electric current Ix、IyAnd IzIt is obtained by excitation source output.
Preferably, also by changing electric current Ix、IyAnd IzFrequency, phase and amplitude current transformer is interfered, survey
The mode of induced voltage signal caused by examination secondary winding in current transformer is measured again.
Preferably, the induced voltage signal measured the secondary winding in current transformer is calculated by the following formula
Obtain shielding parameter：
Δ U is the induced voltage that current transformer generates under alternating current magnetic field, and SE is Magnetic Shielding Effectiveness；H is space magnetic field
Size.
A kind of system for testing current transformer magnetic screen using three-dimensional magnetic field, it is characterised in that：Including computer, excitation
Source, magnetic field generator, signal adapter and mV tables, the computer generate I by RS232 line traffic control excitation sourcesx、Iy、IzRespectively
Generate three-dimensional rotation magnetic field into magnetic field generator, each azimuth scan carried out to current transformer, current transformer it is secondary around
Group N2After the induced current of generation is by signal adapter, the induced voltage of secondary winding is measured by mV tables, then mV tables are surveyed
The induced voltage that amount is read passes to computer and carries out data processing.
Preferably, the current transformer is placed at the three-dimensional magnetic field space center of magnetic field generator generation.
Preferably, the magnetic field generator includes three yokes, three groups of cartridges, three groups of magnet exciting coils and three groups of binding posts,
Perpendicular quadrature, three groups of binding posts are fixedly installed on the outside at three yoke pairwise orthogonals respectively two-by-two between three yokes
Both sides, three groups of magnet exciting coils are wound on respectively on three groups of cartridges, and the magnet exciting coil coiling direction on same axis is consistent, and is leaned on
One end of nearly yoke is connected to corresponding binding post and is passed through identical electric current, ensures that coaxial cartridge generates magnetic field in the same direction.
In conclusion the present invention, as a result of above technical scheme, the present invention has following remarkable result：
The present invention is using three-dimensional rotation magnetic-field measurement current transformer, the electromagnetic shielding performance of current sensor or voltage transformer
Can, the shielding material for current transformer, current sensor or voltage transformer is chosen and the design of structure provides foundation.It is right
Electric energy meter interior layout and quality control have guiding significance, achieve the purpose that improve electric energy meter metering accuracy.
Description of the drawings
In order to illustrate more clearly of present example or technical solution in the prior art, to embodiment or will show below
Required attached drawing, which is done, in having technology to describe simply introduces, it should be apparent that, the accompanying drawings in the following description is only the present invention
Some examples to those skilled in the art, can also be attached according to these under the premise of not paying creativeness
Figure obtains other attached drawings.
Fig. 1 is space magnetic field polar plot.
Fig. 2 is the spherical surface magnetic field sources polar plot of different radii.
Fig. 3 is a kind of schematic diagram for testing current transformer magnetic shielding system using three-dimensional magnetic field of the present invention.
Fig. 4 is the magnetic field generator structure figure of the present invention.
Fig. 5 is the 2 d plane picture in the directions XOY of the magnetic field generator magnetic of the present invention.
Fig. 6 is the current transformer Magnetic Shielding Effectiveness test schematic of the present invention.
Fig. 7 is the electric transducer device Magnetic Shielding Effectiveness test schematic of the present invention.
Specific implementation mode
Below in conjunction with the attached drawing in present example, technical solution in the embodiment of the present invention carries out clear, complete
Ground describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on hair
Embodiment in bright, the every other implementation that those of ordinary skill in the art are obtained without creative efforts
Example, shall fall within the protection scope of the present invention.
In conjunction with Fig. 3, a method of using three-dimensional rotation measurement of magnetic field current transformer magnetic screen, filled by external excitation
Set the electric current I on one group of three direction of (excitation source) applicationx、IyAnd IzIt respectively enters magnetic field generator and generates three orthogonal rotations
Three-dimensional magnetic fieldWithThe space spherical surface magnetic field H of different radii is formed, and to the current transformer in magnetic field space
Each azimuth scan is carried out, and current or voltage inductive signal caused by the secondary winding N to current transformer measures, so
The voltage or current signal of current transformer measurement are calculated by the following formula and obtain shielding parameter afterwards：
In formula, Δ U=Δ I × R,
Wherein, Δ I is the induced current that current transformer generates under alternating current magnetic field, unit：Ampere (A)；Δ U is electric current
The induced voltage that mutual inductor generates under alternating current magnetic field, unit：Millivolt (mV)；R is sample resistance, unit：Ohm (Ω)；H is
The size of space magnetic field, unit：Amperes per meter (A/m)；SE is Magnetic Shielding Effectiveness, unit：Millivolt/(amperes per meter) (mV/ (A/
m))。
As shown in figure 3, a kind of system for testing mutual inductor magnetic screen, including computer, excitation source, magnetic field generation
Device, signal adapter and mV tables, the computer generate I by RS232 line traffic control excitation unitsx、Iy、IzRespectively enter magnetic field
Generator generates the rotating excitation field space of three-dimensional orthogonal, and the current transformer sense that three-dimensional rotation magnetic space is placed in electricity carries out each side
Bit scan, the secondary winding N of current transformer2After the induced current of generation is by signal adapter, pass through milivoltmeter (mV tables)
The induced voltage of secondary winding is measured, then the induced voltage read will be measured and pass to computer progress analyzing processing, the letter
Number converter is I/V or V/V converters.
As shown in figure 4, the magnetic field generator includes three yokes, three groups of cartridges, three groups of magnet exciting coils and three groups of wiring
Column, perpendicular quadrature, three groups of binding posts are fixedly installed on respectively at three yoke pairwise orthogonals two-by-two between three yokes
Both sides external, three groups of magnet exciting coils are wound on respectively on three groups of cartridges, and the magnet exciting coil coiling direction on same axis needs unanimously, and
Coaxial magnet exciting coil flows into identical electric current, ensures coaxial cartridge, generates magnetic field in the same direction, the current transformer is placed in
At the three-dimensional magnetic field space center that magnetic field generator generates.
In the present invention, in conjunction with Fig. 4 and Fig. 5, three yokes of the magnetic field generator are respectively the yoke 3 of X-direction, Z
The yoke 2 in direction and the yoke 1 of Y-direction, the binding post x incoming transport electric currents I of yoke 3x, the binding post z incoming transports of yoke 2
Electric current Iz, the binding post y incoming transport electric currents I of yoke 1y, yoke 1, yoke 2 and yoke 3 perpendicular quadrature two-by-two.Alternating current Ix
Magnet exciting coil X1 and magnet exciting coil X2 is flowed into, the cartridge x2 on the cartridge x1 and magnet exciting coil X2 that are connected on magnet exciting coil X1 is made
Generate the magnetic field of X-direction；Alternating current IyMagnet exciting coil Y1 and magnet exciting coil Y2 is flowed into, the pole being connected on magnet exciting coil Y1 is made
Cartridge y2 on head y1 and magnet exciting coil Y2 generates the magnetic field of Y-direction；Alternating current IZFlow into magnet exciting coil Z1 and magnet exciting coil
Z2 makes the cartridge z2 on the cartridge z1 and magnet exciting coil Z2 that are connected on magnet exciting coil Z1 generate the magnetic field of Z-direction.Cartridge z1 and
Cartridge z2 generates the uniform magnetic field along Z-direction large area, and cartridge x1 and cartridge x2 generate the uniform magnetic along X-axis large area
, cartridge y1 and cartridge y2 generate the uniform magnetic field along Y-axis large area；Cartridge z1 and cartridge z2 are generated along Z axis large area
Uniform magnetic field；Wherein, the cartridge x1 on magnet exciting coil X1 is consistent with the axis of cartridge x2 on magnet exciting coil X2, magnet exciting coil
Cartridge y1 on Y1 is consistent with the axis of cartridge y2 on magnet exciting coil Y2, the cartridge Z1 on magnet exciting coil Z1 and magnet exciting coil Z2
With the axis of cartridge Z2 it is consistent.Fig. 5 is the 2 d plane picture on the directions XOY of magnetic field generator, can be by current transformer
Or current sensor is put at the center of cartridge at (center in magnetic field), access electric current Ix、IyAnd IzGenerated three-dimensional rotation magnetic afterwards
Field carries out each azimuth scan to current transformer or current sensor, and the secondary winding of current transformer or current sensor is made to produce
Raw induced current obtains induced voltage Δ U, you can calculate the shield effectiveness of current transformer after amplification is converted.
Embodiment 1：
In conjunction with shown in Fig. 1 and Fig. 6, current transformer Magnetic Shielding Effectiveness is tested, computer passes through RS232 line traffic controls
Excitation unit (excitation source) generates Ix、Iy、IzIt is respectively connected to the binding post of magnetic field generator, electric current Ix、Iy、IzIt respectively enters respectively
Magnet exciting coil generate three-dimensional rotation magnetic field, when space magnetic field carries out comprehensive scanning to current transformer, current transformer
Secondary winding N2Induced current Δ I, Δ I are generated after I/V converters, then measures to read through milivoltmeter (mV tables) and be incuded
Voltage Δ U calculates its Magnetic Shielding Effectiveness SE, has then reacted the shield effectiveness of current transformer shielding box, wherein：
Δ I is the induced current (A) that current transformer generates under alternating current magnetic field, and Δ U is current transformer in AC magnetism
The induced voltage (mV) generated off field, R are sample resistance (Ω), and SE is Magnetic Shielding Effectiveness, mV/ (A/m).
In the present embodiment, it can also adjust Ix、Iy、IzAmplitude generate different spherical surface magnetic field H, systematic survey to difference
Induced voltage Δ U1, the SE of different direction is calculated, while I can also be changedx、Iy、IzFrequency and phase change space magnetic
The frequency and phase of field source, carry out different tests.
Embodiment 2：
In conjunction with shown in Fig. 3 and Fig. 7, current sensor Magnetic Shielding Effectiveness is tested, computer passes through RS232 line traffic controls
Excitation unit (excitation source) generates Ix、Iy、IzIt is respectively connected to the binding post of magnetic field generator, electric current Ix、Iy、IzIt respectively enters respectively
Magnet exciting coil generate three-dimensional rotation magnetic field, when space magnetic field carries out comprehensive scanning to current sensor, current sensor
Secondary winding N2Induced voltage is generated, induced voltage is after V/V converters, then measures to read through milivoltmeter (mV tables) and be felt
Answer voltage Δ U, its Magnetic Shielding Effectiveness SE of calculating current sensor.Adjust Ix、Iy、IzAmplitude generate different spherical surface magnetic field
H, systematic survey to different induced voltage Δ U1, the SE of different direction is calculated, then has reacted the screen of current sensor shielding box
Effect is covered, wherein：
In formula：Δ U is the induced voltage (mV) that current transformer generates under alternating current magnetic field, and SE is Magnetic Shielding Effectiveness (mV/
), A/m H is the size (A/m) of space magnetic field.
In the present embodiment, while I can also be changedx、Iy、IzFrequency and phase change the frequency in space magnetic field source
And phase, carry out different tests.
The foregoing is merely the preferred embodiments of invention, are not intended to limit the invention, all spirit in the present invention
Within principle, any modification, equivalent replacement, improvement and so on should all be included in the protection scope of the present invention.
Claims (3)
1. a kind of method for testing current transformer magnetic screen using three-dimensional magnetic field, it is characterised in that：Apply electric current by outside
Ix、IyAnd IzThree groups of Exciting Windings for Transverse Differential Protection for respectively enteing magnetic field generator generate three quadrature fieldsWithIt is formed different
The space spherical surface magnetic field H of radius carries out each azimuth scan to current transformer, while measurement current transform er secondary winding is produced
Raw inductive signal, and the Magnetic Shielding Effectiveness of current transformer is calculated；The electric current Ix、IyAnd IzIt is exported by excitation source
And it obtains；Also by changing electric current Ix、IyAnd IzFrequency, phase and amplitude current transformer is interfered, test electric current it is mutual
The mode of induced voltage signal caused by sensor secondary winding is measured again.
2. a kind of method for testing current transformer magnetic screen using three-dimensional magnetic field according to claim 1, feature exist
In：The induced voltage signal that the secondary winding in current transformer measures is calculated by the following formula and obtains shielding ginseng
Number：
Δ U is the induced voltage that current transformer generates under alternating current magnetic field, and SE is Magnetic Shielding Effectiveness；H is the big of space magnetic field
It is small.
3. a kind of system for testing current transformer magnetic screen using three-dimensional magnetic field, it is characterised in that：Including computer, excitation
Source, magnetic field generator, signal adapter and mV tables, the computer generate I by RS232 line traffic control excitation sourcesx、Iy、IzRespectively
Generate three-dimensional rotation magnetic field into magnetic field generator, each azimuth scan carried out to current transformer, current transformer it is secondary around
Group N2After the induced current of generation is by signal adapter, the induced voltage of secondary winding is measured by mV tables, then mV tables are surveyed
The induced voltage that amount is read passes to computer and carries out data processing；The current transformer is placed in the three of magnetic field generator generation
It ties up at magnetic field space center；The magnetic field generator includes three yokes, three groups of cartridges, three groups of magnet exciting coils and three groups of wiring
Column, perpendicular quadrature, three groups of binding posts are fixedly installed on respectively at three yoke pairwise orthogonals two-by-two between three yokes
Both sides external, three groups of magnet exciting coils are wound on respectively on three groups of cartridges, and the magnet exciting coil coiling direction on same axis is consistent,
Electric current flows into magnet exciting coil by binding post, and coaxial magnet exciting coil accesses identical electric current, ensures that coaxial cartridge generates
Magnetic field in the same direction.
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| CN109239469B (en) * | 2018-08-16 | 2021-11-02 | 江苏赛诺格兰医疗科技有限公司 | Device and method for detecting magnetic shielding effect of magnetic shielding material under low magnetic field |
| CN111766550A (en) * | 2020-07-08 | 2020-10-13 | 致真精密仪器(青岛)有限公司 | Three-dimensional magnetic field probe station test system and test method |
| CN112134468B (en) * | 2020-09-29 | 2022-03-08 | 陕西省计量科学研究院 | Alternating current phase-adjustable power supply based on rotating magnetic field |
| CN112834894B (en) * | 2021-01-07 | 2022-06-28 | 清华大学 | A magnetic field testing device for semiconductor current density inversion |
| CN114200360B (en) * | 2021-11-10 | 2023-08-15 | 北京自动化控制设备研究所 | Three-dimensional coil magnetic field uniformity test method and system |
Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1877354A (en) * | 2005-06-10 | 2006-12-13 | 株式会社日立高新技术 | Magnetic field measuring device |
| CN101661018A (en) * | 2009-09-23 | 2010-03-03 | 帅立国 | Three-dimensional electromagnetic probe and gyromagnetic detection method |
| CN101934248A (en) * | 2009-07-01 | 2011-01-05 | 广西远健选矿工程技术研究院 | Oil-cooled turntable high-gradient magnetic separator |
| CN102853760A (en) * | 2012-09-13 | 2013-01-02 | 哈尔滨工业大学 | Method for calibrating verticality of magnetic shaft of three-shaft magnetic sensor |
| CN202770984U (en) * | 2012-09-20 | 2013-03-06 | 上海市计量测试技术研究院 | Magnetic material shielding property self-evaluating device |
| CN103728585A (en) * | 2013-10-30 | 2014-04-16 | 国家电网公司 | Device and method for testing noise immunity of power frequency magnetic field of electric energy meter |
| CN103887036A (en) * | 2014-03-13 | 2014-06-25 | 中国计量科学研究院 | Gradient field electromagnet for permanent magnet temperature coefficient open circuit measurement |
| CN104123408A (en) * | 2014-07-03 | 2014-10-29 | 国家电网公司 | Method for preventing intelligent electric meter from external electromagnetic field interference based on finite element simulation analysis |
| CN204439727U (en) * | 2015-02-16 | 2015-07-01 | 第二炮兵工程设计研究院 | A kind of shield effectiveness test macro |
| CN104865468A (en) * | 2015-05-15 | 2015-08-26 | 中国人民解放军理工大学 | Device and method for measuring shielding effectiveness of electromagnetic pulse of thunder and lightning |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5168051B2 (en) * | 2008-09-25 | 2013-03-21 | 富士通株式会社 | Electromagnetic field analysis program and electromagnetic field analysis apparatus |
-
2015
- 2015-11-25 CN CN201510833065.9A patent/CN105301549B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1877354A (en) * | 2005-06-10 | 2006-12-13 | 株式会社日立高新技术 | Magnetic field measuring device |
| CN101934248A (en) * | 2009-07-01 | 2011-01-05 | 广西远健选矿工程技术研究院 | Oil-cooled turntable high-gradient magnetic separator |
| CN101661018A (en) * | 2009-09-23 | 2010-03-03 | 帅立国 | Three-dimensional electromagnetic probe and gyromagnetic detection method |
| CN102853760A (en) * | 2012-09-13 | 2013-01-02 | 哈尔滨工业大学 | Method for calibrating verticality of magnetic shaft of three-shaft magnetic sensor |
| CN202770984U (en) * | 2012-09-20 | 2013-03-06 | 上海市计量测试技术研究院 | Magnetic material shielding property self-evaluating device |
| CN103728585A (en) * | 2013-10-30 | 2014-04-16 | 国家电网公司 | Device and method for testing noise immunity of power frequency magnetic field of electric energy meter |
| CN103887036A (en) * | 2014-03-13 | 2014-06-25 | 中国计量科学研究院 | Gradient field electromagnet for permanent magnet temperature coefficient open circuit measurement |
| CN104123408A (en) * | 2014-07-03 | 2014-10-29 | 国家电网公司 | Method for preventing intelligent electric meter from external electromagnetic field interference based on finite element simulation analysis |
| CN204439727U (en) * | 2015-02-16 | 2015-07-01 | 第二炮兵工程设计研究院 | A kind of shield effectiveness test macro |
| CN104865468A (en) * | 2015-05-15 | 2015-08-26 | 中国人民解放军理工大学 | Device and method for measuring shielding effectiveness of electromagnetic pulse of thunder and lightning |
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