CN106018915B - Current detector - Google Patents
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- CN106018915B CN106018915B CN201610192052.2A CN201610192052A CN106018915B CN 106018915 B CN106018915 B CN 106018915B CN 201610192052 A CN201610192052 A CN 201610192052A CN 106018915 B CN106018915 B CN 106018915B
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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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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/20—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices
- G01R15/202—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using galvano-magnetic devices, e.g. Hall-effect devices, i.e. measuring a magnetic field via the interaction between a current and a magnetic field, e.g. magneto resistive or Hall effect devices using Hall-effect devices
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- General Physics & Mathematics (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measuring Magnetic Variables (AREA)
Abstract
The present invention provides current detector, is a kind of technology without eliminating the influence of magnetic hysteresis with easy structure with complicated movement.The current detector (100) has: magnetic material core (102), it is configured along the circular direction in the magnetic field generated when sensed current (If) is connected with ring-type, and the gap 102d of configuration Hall element (106) is formed in a part；And degaussing circuit (150), it is directed to the alternating current that the demagnetization for being set to magnetic material core (102) has scheduled attenuation characteristic with coil (156) with the frequency application in preset range, thus eliminates the remaining magnetic flux in magnetic material core (102).
Description
Technical field
The electric current of the type for the magnetic flux that the present invention relates to the use of magnetic core and generated to collect the conducting based on sensed current
Detector.
Background technique
There is following such problems in this current detector using the type of magnetic core, i.e., when in movement in leading
When generated in vivo well beyond the overcurrent of rated value, due to magnetic core relict flux and (residual is had an impact to detection accuracy
So-called magnetic hysteresis).Therefore, at present in the DC current sensor with detection magnetic core and detection coil, there is known be conceived to
The prior art of the magnetic hysteresis of detection magnetic core is eliminated (for example, referring to patent document 1.).
The prior art be related to for make the detection magnetic core that the magnetic field that generates is collected when sensed current is connected with
Vertical direction connection makes the DC current sensor of excitation being integrally formed of magnetic core of part of it generation magnetic gaps, as electricity
Flow sensor is extremely special form.Although making detection magnetic that is, generating alternating magnetic field with the integrated excitation magnetic core of detection magnetic core
A part of core periodically becomes magnetic gap state, but in gap is formed, and magnetic switch is shutdown, disappears in gap
In, magnetic switch is to connect, so electromotive force can be generated in detection coil repeatedly using this, carries out current detecting.But In
The influence for the coercive force having under this state due to soft magnetic material and cause to produce the output voltage from detection coil
The hysteresis of (output characteristics), therefore to make to produce in modulation coil by further configuring modulation coil to detection magnetic core
Raw alternating magnetic field is Chong Die with detection magnetic core and measures the DC current flowed in being detected conducting wire, to eliminate above-mentioned guarantor's magnetic
The influence of power.
Herein on basis, the prior art is conceived to when being powered in current detecting to modulation coil, small
Galvanic areas in detection circuit electrically reaching saturation, thus be difficult to from the signal obtained by detection coil separate adjust
Ac current signal processed and the such situation of tested constant current signal during resetting de- magnetic, become completely de- magnetic state, then
During setting detection, to prevent the electricity saturation of detection circuit.
Existing technical literature
Patent document
Patent document 1: Japanese Unexamined Patent Publication 10-68744 bulletin (paragraph 0018-0023 etc.)
Summary of the invention
Problems to be solved by the invention
But the above-mentioned prior art has difficulty in the complexity based on its specific form.That is, to original inspection
It surveys magnetic core and excitation magnetic core is added in the structure of modulation coil, in order to remove magnetic caused by the coercive force that detection magnetic core has
It is stagnant, and make the alternating magnetic field generated in modulation coil specially with detection magnetic core carry out it is be overlapped, but here obvious detection coil with
Detection circuit is attached always.However, needing to prevent the electricity saturation of detection circuit in during the de- magnetic reset, connect down
Carry out the separation detection coil from detection circuit, also, during de- magnetic at the end of must be reconnected again it is such multiple
Miscellaneous movement.
Therefore, the present invention provides the influences without eliminating magnetic hysteresis with complicated movement, using easy structure
Technology.
The means solved the problems, such as
In order to solve above-mentioned problem, the present invention uses solution below.
That is, the present invention is to configure magnetic detecting element in the gap formed in magnetic material core to detect the type of electric current
Current detector is suitble to so-called opening, orthodox form as servo type type.
Herein basis on, the present invention have degaussing circuit, the degaussing circuit be directed to be arranged in magnetic material core around
Group is applied the alternating current with scheduled attenuation characteristic with the frequency in preset range, thus eliminated in magnetic material core
Remaining magnetic flux.
Current detector according to the present invention, even if generating the shadow of the magnetic hysteresis as caused by the relict flux of magnetic material core
It rings, also can remove magnetic hysteresis using the alternating current that degaussing circuit is applied.In addition, because of the measurement in sensed current
Magnetic detecting element is used in (detection of electric current), so not needing in the application with the alternating current caused by degaussing circuit
Compound action as any electrical connection, later re-attached is separated, easy structure can be become.
In the present invention, degaussing circuit is preferably in such a way that the frequency in the range of 8kHz to 17kHz applies alternating current.
The range of such frequency is unrelated with other characteristic such as the rated value of sensed current or the coercive force of magnetic material core, has
Versatility.It therefore, there is no need to scrutinize an other characteristic in advance to determine frequency, simple and high convenience electric current inspection can be obtained
Survey device.
In addition, in the present invention, degaussing circuit, which applies, is used as scheduled attenuation characteristic, and die-away time is 5ms to 1000ms
Alternating current.In addition, because completing magnetic caused by the relict flux of removal magnetic material core after by die-away time
It is stagnant, so not needing to apply alternating current repeatedly later, the detection of electric current can be directly proceeded with.
Current detector of the invention may be configured as the servo type with feed circuit.In the case, degaussing circuit can
Alternating current is applied to the secondary winding of feed circuit.It does not need that other dedicated windings are arranged as a result, it will be able to by winding
Usage amount is suppressed to less.
In addition, in the present invention, degaussing circuit preferably since at the time of starting the conducting of sensed current alternating current
The mode of the application of stream.Alternatively, degaussing circuit can start to apply from the time of starting to supply driving power to magnetic detecting element
Add alternating current.
That is, the conducting of sensed current starts or starts to mean the supply of magnetic detecting element supply driving power to answering
At the time of putting into power supply with certain systems (electrical equipment) of current detector of the invention.Pass through demagnetization electricity at the time of such
Road starts to apply alternating current, and decays with it and remove the influence of magnetic hysteresis together, can make power supply of the current detector from system
Investment is just stablized at the beginning of starting and is accurately proceed detection operation.
Invention effect
According to the present invention, it is not necessary that the influence of magnetic hysteresis can be eliminated with easy structure with complicated movement.
Detailed description of the invention
Fig. 1 is the perspective view for briefly showing the structure of current detector of the 1st embodiment.
Fig. 2 is the figure for briefly showing the waveform for the alternating current that degaussing circuit applies demagnetization coil.
Fig. 3 is the experimental model (current detecting briefly shown for confirming the magnetic hysteresis removal effect for using degaussing circuit
Device sampling) structure figure.
Fig. 4 is the figure for showing the result of magnetic hysteresis removal test.
Fig. 5 is the figure for showing the result of the magnetic hysteresis removal effect when frequency of alternating current to be set as to 10kHz.
Fig. 6 is the figure for being made the relationship of the virtual value and magnetic hysteresis variable quantity of alternating current curved according to the measurement result of Fig. 5.
Fig. 7 (A), Fig. 7 (B) are the various asynchronous examinations of condition holding for showing the frequency and current value that make the electric current applied
Test the figure of result.
Fig. 8 (A), Fig. 8 (B) are the various asynchronous examinations of condition holding for showing the frequency and current value that make the electric current applied
Test the figure of result.
Fig. 9 is the skeleton diagram for showing the structure of current detector of the 2nd embodiment.
Figure 10 is the skeleton diagram for showing the structure of current detector of the 3rd embodiment.
Figure 11 be show the 1st, the 2nd, the skeleton diagram of the structure of the degaussing circuit of the 3rd embodiment.
Label declaration
100,200,300 current detector
102 magnetic material cores
The gap 102d
104 secondary windings
106 Hall elements
108 special circuits
150 degaussing circuits
Specific embodiment
Hereinafter, being explained with reference to embodiments of the present invention.
[the 1st embodiment]
Fig. 1 is the skeleton diagram for showing the structure of current detector 100 of the 1st embodiment.Hereinafter, illustrating current detector
100 structure.
[magnetic material core]
Current detector 100 has the magnetic material core 102 for for example using permalloy in the material, the magnetic material core
102 constitute approximate square ring shape as a whole.The electricity of approximate rectangular shape is formed in the inside (inner circumferential of ring) of magnetic material core 102
Conducting portion 102a is flowed, conductors 105 (first winding) such as bus (bus bar) are inserted in current lead-through portion 102a.Electric current inspection
Device 100 is surveyed, as test object, to produce by the electric current of conductor 105 along when flowing sensed current (If) in conductor 105
The circular direction in raw magnetic field annularly configures magnetic material core 102.In addition, being relatively low water in sensed current (If)
When quasi- (weak current), conductor 105 can be wound in magnetic material core 102.
[gap]
As described above, magnetic material core 102 constitutes approximate square ring shape, therefore, contains respectively in magnetic material core 102
There is a pair of short edges portion 102b and long leg 102c.In addition, long in magnetic material core 102, such as by partly cutting 1
The midway of edge 102c forms gap 102d.In addition, gap 102d can be formed in short leg 102b.
[magnetic detecting element]
Current detector 100 uses an example of element as magnetic force detection, and having Hall element 106 (can be MR element, MI
Element).Hall element 106 is installed in magnetic material core 102 in the state of being inserted into the 102d of gap.In addition, Hall
Element 106 is the electronic component being for example packaged by resin seal, in each Hall element 106, such as by not
The power circuit of diagram supplies driving voltage (such as+5V).The magnetic field that Hall element 106 is exported and generated in the 102d of gap
The corresponding voltage signal (Hall voltage) of intensity (magnetic flux).
[special circuit]
In addition, current detector 100 has special circuit 108.The special circuit 108 is, for example, towards the 1st embodiment
The current detector 100 of such servo type makes the electronic component of structural optimization and the circuit in the design of internal package specific
(discrete (discrete) product).In special circuit 108, in addition to from power circuit (not shown) supply driving voltage (such as+
Except 5V), the voltage signal exported from Hall element 106 is also inputted.In addition, special circuit 108 has as reference port
REFIN and REFOUT (such as+2.5V).
[feed circuit]
As described above, the current detector 100 of the 1st embodiment is servo type, therefore is had as feed circuit
Constituent element.Feed circuit also has other than having differential amplifier (not shown) for example in above-mentioned special circuit 108
There is the secondary winding 104 connecting with special circuit 108.For example, a long leg 102c's for being wound in magnetic material core 102
Secondary winding 104 is formed under state.Secondary winding 104 is supplied according to the voltage signal from Hall element 106 in Special electric
The feedback current (Ih) generated in road 108, is thus produced in a manner of offsetting the direction in magnetic field caused by sensed current (If)
Raw counter field.In addition, being provided with load resistance 110 in a feedback circuit, the electric current output (Ih) of secondary winding 104 is via load
Resistance 110 is converted to voltage output (Vout).
[degaussing circuit]
In addition, current detector 100 has degaussing circuit 150.The degaussing circuit 150 eliminates the residual of magnetic material core 102
Stay magnetic flux (so-called magnetic hysteresis removal).Therefore, it is distinctively wound with and disappears with above-mentioned secondary winding 104 in magnetic material core 102
Magnetic coil 156, degaussing circuit 150 apply alternating current to demagnetization coil 156.Specifically, degaussing circuit 150 has vibration
Swing circuit 152 and attenuator circuit 154.Wherein, oscillating circuit 152 generates alternating current, decaying electricity with the frequency of preset range
Road 154 is applied on demagnetization coil 156 after so that it is decayed.
Degaussing circuit with oscillating circuit and attenuator circuit for example can circuit as shown in Figure 11 constitute.Resistance R, capacitor
C, the constant of inductance L is not limited by the constant of Figure 11, can be suitably changed.
[AC wave shape]
Fig. 2 is the figure for briefly showing the waveform for the alternating current that degaussing circuit 150 applies demagnetization coil 156.
The oscillating circuit 152 of degaussing circuit 150 generates the alternating current (Ipp) for example indicated with following formula.
Ipp=Vh/VgainIf
In above formula,
Vh: hysteresis voltage
Vgain:0.625V
If: sensed current (rated value).
In addition, the frequency of alternating current (Ipp) is set in the range of 8kHz~17kHz.Attenuator circuit 154 makes to exchange
Electric current (Ipp) is decayed with time going by, causes current value to become 0 greatly in die-away time Ts since applying.Here, will
Die-away time, Ts was for example set as 50ms.In addition, die-away time Ts can be for example set in the range of 5ms~1000ms.
[setting of frequency range]
Here, illustrate the basis that the frequency by alternating current (Ipp) is set in the range of 8kHz~17kHz., based on
Under test come setpoint frequency range.
[magnetic hysteresis removal test]
Fig. 3 is experimental model (the electric current inspection briefly shown for confirming the magnetic hysteresis removal effect for using degaussing circuit 150
Survey device sampling) structure figure.In experimental model, such as it is made into the electricity that test magnetic core 302 is the laminated type of silicon steel plate
Current sensor.In addition, in test with winding above-mentioned demagnetization coil 156 on magnetic core 302, and connect degaussing circuit 150.Another party
Face in the test monitoring coil 5 of winding flux change on magnetic core 302, and makes its connect voltage monitor 160.Furthermore this
In, demagnetization is, for example, 13 circles with the writhing number of coil 156, and monitoring is, for example, 5 circles with the writhing number of coil 5.
[experimental condition]
Magnetic hysteresis removal test for example carries out under the following conditions.
(1) demagnetization is carried out using magnetic core 302 of the demagnetizer to experiment current detector, connects power supply ± 15V, utilizes ten thousand
Bias voltage is measured with table.
It (2) is shutdown by the power settings of experiment current detector.It is passed through in the magnetic core 302 to experiment current detector
After logical 10 times of rated current, becomes power supply and connect.The bias voltage of measurement experiment current detector.
(3) it is powered to demagnetization with coil 156, monitors excitation waveform using voltage monitor 160, when can observe
When to excitation waveform, erasure effect is viewed as " having ".Turn off the signal of anti-magnetized coil 156, measurement experiment current detecting
The output voltage (bias voltage) of device makes the variation of the bias voltage of the movement of anti-magnetized coil 156 front and back have erasure effect.
(4) after above-mentioned (3), excitation temporarily is carried out with magnetic core 302 to test, test magnetic core 302 is made to generate residual
Magnetic flux.Become 43.8A × 13 (the number of turns)=570AT by electric current.
(5) then, it acts degaussing circuit 150 in a manner of removing magnetic hysteresis, and applies the friendship with attenuation characteristic
Galvanic electricity stream.
[test result]
Fig. 4 is the figure for showing the result of magnetic hysteresis removal test.Here, 10 tests (No.1~No.10) are carried out, are made each
The various values of secondary middle acquisition become guide look.In addition, being tested in a manner of each frequency for changing application electric current.
[measurement item]
The measurement item in test (frequency is based on setting) is as described below every time.
(1) bias voltage after demagnetization: Voffset (mV)
(2) magnetic hysteresis after excitation: VH (mV)
(3) apply RMS value (A) × 13T: the winding several times of the alternating current as application of electric current.
(4) magnetic hysteresis removal frequency (Hz): set frequency.
(5) bias voltage after electric current applies (after demagnetization test): VOFFSET (mV)
(6) magnetic hysteresis removal effect (mV): making the difference of Voffset and VOFFSET becomes removal effect.
(7) waveform: the voltage RMS value of VRMS (mV), the waveform monitored with voltage monitor 160 is monitored.
Hereinafter, illustrating test result.
[the 1st test]
In Fig. 4, as shown in the test result of " No.1 ", when the frequency of the alternating current of application is set as 10Hz,
Certain values (- 9.29mV) are obtained as magnetic hysteresis removal effect (VOFFSET-Voffset), but do not observe monitoring waveform.
[the 2nd test]
Then, in Fig. 4, it is set as 10 as shown in the test result of " No.2 ", but by the frequency of the alternating current of application
Times 100Hz when, obtain certain values (- 5.80mV) as identical magnetic hysteresis removal effect (VOFFSET-Voffset), but still
Monitoring waveform is not observed so.
[the 3rd test]
Then, it in Fig. 4, as shown in the test result of " No.3 ", is also set to when by the frequency of the alternating current of application
When 10 times of 1kHz, here also as the certain values (- 9.60mV) of magnetic hysteresis removal effect (VOFFSET-Voffset) acquisition, but according to
Monitoring waveform is not observed so.
[the 4th test]
Therefore, in Fig. 4, as shown in the test result of " No.4 ", the frequency of the alternating current of application is set as by this
8kHz.As a result, obtaining good value (- 11.25mV) as magnetic hysteresis removal effect (VOFFSET-Voffset), and observe
It monitors waveform (120mV).
[the 5th test]
Then, in Fig. 4, as shown in the test result of " No.5 ", the frequency of the alternating current of application is set as
17kHz.Here good value (- 8.33mV) is obtained and as magnetic hysteresis removal effect (VOFFSET-Voffset), and is seen
Measure monitoring waveform (156mV).
[after the 6th test]
In addition, in Fig. 4, as shown in the test result of " No.6 "~" No.8 ", even if by the frequency of the alternating current of application
Rate is gradually increased as 20kHz, 25kHz, 30kHz, also obtain magnetic hysteresis removal effect value (- 8.68mV, -12.00mV, -
9.12mV), monitoring waveform (192mV, 307mV, 355mV) is observed.
Equally, the test result of " No.9 " and " No.10 " in Fig. 4 be set separately frequency be increased to 50kHz,
100kHz.In these trials, the value (- 10.75mV, -11.88mV) of magnetic hysteresis removal effect is obtained, and observes monitoring waveform
(575mV、1060mV)。
[summary (1) of test result]
According to above test result " No.1 "~" No.10 ", following situation can be specified.
(i) when but applying alternating current with coil 156 to the demagnetization of current detector sampling, magnetic hysteresis is obtained as a result and is gone
The effect removed.
(ii) wherein, because there is no monitoring waveform in the frequency domain lower than 8kHz, in these lower frequency regions (10Hz
~1000Hz) under, without display flux change in test magnetic core 302.
(iii) on the other hand, because monitoring waveform is obtained in the high-frequency domain of 8kHz or more, it is known that in test magnetic
The frequency for occurring flux change in core 302 is 8kHz or more.
[measurement of magnetic hysteresis removal effect]
Therefore, after the frequency of the alternating current of application is set as 10kHz, repeatedly (being here 12 times) examination is also carried out
It tests, and determines each magnetic hysteresis removal effect.In addition, experimental condition is same as shown in Figure 4.In this experiment, make every time
The RMS value of the alternating current of application is changed.
Fig. 5 is the figure for showing the result of the magnetic hysteresis removal effect when frequency of alternating current to be set as to 10kHz.In addition,
Fig. 6 is the figure that the virtual value of alternating current and the relationship of magnetic hysteresis variable quantity are drawn according to the measurement result of Fig. 5." magnetic hysteresis in Fig. 5
Removal effect (mV) " is the difference of " magnetic hysteresis VH (mV) after excitation " and " Voffset (mV) ".In addition, in " monitoring waveform VRMS
(mV) " the case where being " ok " in column is to indicate to observe effective waveform.In addition, about each time " No.1 "~" No.12 "
In each measured value referring in detail to the content of diagram, omit the content referred to individually here.
[summary (2) of test result]
According to above test result (No.1~No.12 and Fig. 6 in Fig. 5), following situation can be specified.
(i) when applying alternating current with coil 156 to demagnetization with the frequency of 10kHz, because inclined in all numbers
Set the effective variation of discovery in voltage, it is known that there is magnetic hysteresis removal effect.
(ii) (absolute with the variable quantity of its bias voltage that accompanies at this point, when increasing the virtual value of the alternating current applied
Value) whole bigger tendency is also presented (there is deviation slightly).
[embodiment]
According to the test result of the current detector sampling more than using, the servo type of the 1st embodiment shown in Fig. 1
Current detector 100 in actually carried out magnetic hysteresis removal test.The purpose of this test is, as cutting actual use electricity
The state of the power supply of the system (such as refrigerator) of current sensor 100 passes through 10 times of direct current of rated value in conductor 105
When stream, the removal of degaussing circuit 150 remaining magnetic hysteresis in magnetic material core 102 is utilized.
[theory speculates]
Here, before actual test, according to the raw material of magnetic material core 102 and (the discrete production of special circuit 108
Product) characteristic, theoretical property below, which speculates, to be set up.
(a) bias voltage (VOFFSET)=2.5V, rated current If=7A
(b) above-mentioned error=± 20mV
(c) the comparable current value of magnetic hysteresis (calculated value): according to the formula of Ipp=Vh/VgainIf, 20/625 × 7=
0.224A=224mA
(d) therefore, the current value of magnetic hysteresis removal in the range of 0mA to 224mA on one side fluctuation while decay.
[test result]
Fig. 7 (A), Fig. 7 (B) and Fig. 8 (A), Fig. 8 (B) are the conditions for showing the frequency and current value that make the electric current applied
Keep the figure of various asynchronous test results.Fig. 7 (A) therein indicates to make the writhing number of demagnetization coil 156 to become 1 time
Test result when (1T), Fig. 7 (B) and Fig. 8 (A), Fig. 8 (B) indicate to make the writhing number of demagnetization coil 156 to become 5 times
Test result when (5T).About whether there is or not the judgement of magnetic hysteresis removal effect, as long as the bias voltage after test is in theoretic
Bias voltage=2.5V ± 10mV, it is determined that " having ", other than judgement be "None".
Fig. 7 (A): being set as 8kHz for the frequency of alternating current, is tasted using current value shown in each time (No.1~No.5)
Examination removal magnetic hysteresis.It is tested shown in " No.1 " therein~" No.4 " and is all determined as "None" magnetic hysteresis removal effect.Only " No.5 " institute
The test shown becomes " having " magnetic hysteresis removal effect.
Fig. 7 (B): then, being set as 100mA for current value, and the frequency of alternating current is made to change to 11kHz~17kHz
Carry out the test of each time (No.1~No.7).Here be 44.8mA with the comparable electric current virtual value of magnetic hysteresis.As a result, at all times
Middle Voffset is stable at stable value (2.499V), and magnetic hysteresis removal effect is all " having ".
Fig. 8 (A): the frequency for setting alternating current is reduced to 500Hz, utilizes current value shown in each time (No.1~No.4)
To attempt removal magnetic hysteresis.Here be 112mA with the comparable electric current virtual value of magnetic hysteresis.As a result, Voffset becomes in all times
More than the value (2.490V) of permissible range, magnetic hysteresis removal effect is determined as "None".
The frequency of alternating current: being set higher than the 1kHz of Fig. 8 (A) by Fig. 8 (B), utilizes each (No.1~No.4) institute
The current value shown come attempt removal magnetic hysteresis.Here be 112mA with the comparable electric current virtual value of magnetic hysteresis.It but is here also in whole
Secondary middle Voffset becomes the value (2.490V) more than permissible range, determines that magnetic hysteresis removal effect is all determined as "None".
[summary (3) of test result]
According to the test result of the current detector 100 using servo type, following situation can be specified.
(i) in Fig. 7 (A), magnetic hysteresis removal effect is that the lower limit of the frequency of " " is 8kHz.Though it is not particularly illustrated, by
The result of other tests is carried out it is found that when the frequency of the alternating current of application is lower than 8kHz, because high impedance is cannot obtain
Obtain sufficient magnetic hysteresis removal effect.
(ii) in addition, in Fig. 7 (B), magnetic hysteresis removal effect is that the frequency of " " is 11kHz~17kHz.Though not scheming especially
Show, but the result by carrying out other tests, it is found that when frequency is higher than 17kHz, magnetic material core 102 carries out work as ACCT
Make, because servo action stops, sufficient magnetic hysteresis removal effect cannot be obtained.
(iii) range of the optimum frequency of alternating current is 8kHz~17kHz as a result, when with the frequency pair within the scope of this
It, as an example can be in the die-away time Ts suitably set when demagnetization coil 156 applies the alternating current with attenuation characteristic
Magnetic hysteresis removal is completed in (50ms).In addition because can confirm magnetic hysteresis removal effect with frequency 10kHz in Fig. 5 and in Fig. 7
(B) magnetic hysteresis removal effect can be confirmed with the range of 11kHz~17kHz in, so can be described as having in 10kHz~17kHz
It can more be suitble to remove the effect of magnetic hysteresis.
In addition, according to other tests (not shown) as a result, die-away time Ts can be set in the range of 5ms~1000ms
It is interior.The reason is that when die-away time Ts ratio 5ms in short-term, sufficient magnetic hysteresis removal effect cannot be obtained, when die-away time Ts is more than
When 1000ms, the responsiveness (starting time) when starting to system generates baneful influence.
Because die-away time is longer, the time of demagnetization is longer, so can be described as effect height, but needs to consider above-mentioned evil
Bad influence.It therefore, there is no need to become die-away time than above-mentioned Ts long, die-away time can be 5ms~100ms, in addition can be with
As the short time as 5ms~50ms.Erasure effect can be fully obtained in 5ms~50ms.
[the 2nd embodiment]
Fig. 9 is the skeleton diagram for showing the structure of current detector 200 of the 2nd embodiment.In addition, herein in relation to the 1st
The common item of embodiment all marks common symbol including diagram, and omits its repeat description.Hereinafter, will be with the 1st in fact
It applies centered on the difference of mode and illustrates the current detector 200 of the 2nd embodiment.
In the 2nd embodiment, demagnetization coil is not wound to magnetic material core 102, degaussing circuit 150 is via capacitor
158 are connected in parallel with secondary winding 104.Therefore, in the 2nd embodiment, secondary winding 104 can be used for removal magnetic hysteresis
Purposes, and winding usage amount can be accordingly decreased.
In the 2nd embodiment, degaussing circuit 150 is attached via capacitor 158 and feedback coil 104, works as utilization
Make Current Voltage of the AC signal by feedback system after the magnetic hysteresis of the AC signal removal magnetic material core 102 of demagnetization
When conversion precision resister, the value of the outlet side of current detector 200 can be directly observed, but here, make feedback coil 104
Also it is functioned as anti-magnetized coil and demagnetization is carried out to magnetic material core 102, connect thus it enables that current detector 200 becomes
It is logical, the movement of demagnetization is carried out first, then carries out the movement as current detector 200.Therefore, within the erasing time without
Signal as current detector 200 exports (output of current detection value).In addition, static capacity can be used as capacitor 158
It is the capacitor of the μ of 50nF~0.22 F.
The structure of other special circuits 108 or feed circuit is identical as the first embodiment described above, omits its here and says
It is bright.
[the 3rd embodiment]
Figure 10 is the skeleton diagram for showing the structure of current detector 300 of the 3rd embodiment.Here and about with the 1st,
The common item of 2nd embodiment all marks common symbol including diagram, and omits institute's repeat description.Hereinafter, will be with
1, illustrate the current detector 300 of the 3rd embodiment centered on the difference of the 2nd embodiment.
[style of opening]
That is, the difference of the current detector 300 of the 3rd embodiment is to become the style of opening without secondary winding.The
The current detector 300 of 3 embodiments replaces special circuit 108, has amplifying circuit 308, the signal from Hall element 106
It is amplified via amplifying circuit 308, becomes voltage output (Vout).
Even if, also can be by being offseted with the frequency of 8kHz~17kHz in the current detector 300 of such style of opening
Magnetic applies alternating current with coil 156, to be carried out similarly magnetic hysteresis removal with the first and second embodiments.
[action control example]
Then, illustrate the preference of the action control of the current detector 100,200,300 of each embodiment.
In the 1st~the 3rd embodiment, current detector 100,200,300 can be (such as cold by applicable respectively system
Jelly machine) power supply at the time of be turned on from off state (when starting) as starting point, start the movement for removing magnetic hysteresis.
[control examples of the first and second embodiments]
Specifically, becoming following such structure in the control example of the first and second embodiments, examined when to applied current
Survey device 100,200 system put into (shutdown → connection) power supply when, make its as triggering (trigger) from special circuit 108 to
150 output action signal of degaussing circuit.Then, degaussing circuit 150 receives the signal and starts application alternating current, and in control journey
The step of removal magnetic hysteresis is completed in die-away time Ts is previously charged into sequence.After, in the work of system because via demagnetization
0 approximation can be decayed to the electric current of coil 156, so making magnetic material core 102 generate magnetic flux without demagnetization coil 156
The case where.
[control example of the 3rd embodiment]
In addition, the control example of the 3rd embodiment is following such structure, when the corresponding system for using current detector 300
When putting into (shutdown → connection) power supply, as triggering from amplifying circuit 308 to 150 output action signal of degaussing circuit.Disappear
Magnetic circuit 150 receives the signal and starts to apply alternating current, is similarly enclosed in die-away time Ts and completes in a control program
The step of removing magnetic hysteresis.After, because 0 approximation can be decayed to via the electric current of demagnetization coil 156 in the work of system
Value, so the case where making magnetic material core 102 generate magnetic flux without demagnetization coil 156.
According to above-mentioned each embodiment, the dynamic of magnetic hysteresis is removed when the starting of most significant system by influencing in magnetic hysteresis
Make, since the work of system at the beginning of can be accurately proceed the detection of electric current.
The present invention is not restricted by above embodiment, can carry out the later implementation of various modifications.For example, magnetic substance magnetic
The shape of core 102 is not only the four side ring shapes enumerated in various embodiments, is also possible to other polygon ring-shaped, or
Person can be round or elliptical shape.In addition, magnetic material (the iron oxygen other than permalloy can be used in magnetic material core 102
Body (ferrite), silicon steel plate, Fe-Ni alloy etc.) it is made, circular structure or layer can be used in magnetic material core 102
Folded construction.In addition, the specification of the concrete shape of magnetic material core 102, size or thickness etc. can be with being detected really as object
The characteristic for surveying electric current correspondingly suitably changes.
In addition, current detector 100,200,300 or the part of it construction enumerated together with diagram are only preferred one
Example, it is self-evident for adding various elements to basic construction or can be appropriately carried out the present invention replacing a part
's.
Claims (6)
1. a kind of current detector, has:
Magnetic material core is configured along the circular direction in the magnetic field generated when sensed current is connected with ring-type, In
The gap of configuration magnetic detecting element is formed in a part；And
Degaussing circuit is able to carry out following demagnetization movement: by the winding for being set to the magnetic material core to make a reservation for
Frequency in range applies the alternating current with scheduled attenuation characteristic, to eliminate the remaining magnetic in the magnetic material core
It is logical,
When the conducting of the sensed current of the connection due to power supply starts, to the degaussing circuit output action signal,
To start to apply alternating current with the comparable current value of the magnetic hysteresis found out according to the relationship of sensed current and hysteresis voltage, and
And by controlling to obtain the frequency for completing the characteristic to decay within scheduled die-away time, in the scheduled die-away time
Demagnetization movement of the interior completion based on the degaussing circuit, then, starts the detection operation for detecting the sensed current.
2. current detector according to claim 1, which is characterized in that
The degaussing circuit applies the alternating current with the frequency in the range of from 8kHz to 17kHz.
3. current detector according to claim 2, which is characterized in that
Apply the alternating current with the frequency in the range of from 10kHz to 17kHz.
4. current detector according to any one of claims 1 to 3, which is characterized in that
The degaussing circuit, which applies, is used as the scheduled attenuation characteristic, and die-away time is the institute in the range of 5ms to 1000ms
State alternating current.
5. current detector according to claim 4, which is characterized in that
Applying the die-away time is the alternating current in the range of 5ms to 50ms.
6. current detector as claimed in any of claims 1 to 3, which is characterized in that
It is also equipped with feed circuit, which winding feedback current according to the signal exported from the magnetic detecting element
It is connected in the secondary winding of the magnetic material core,
The degaussing circuit applies the alternating current for the secondary winding of the feed circuit.
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| JP2015068510A JP6200445B2 (en) | 2015-03-30 | 2015-03-30 | Current detector |
| JP2015-068510 | 2015-03-30 |
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| EP3812785A1 (en) * | 2019-10-22 | 2021-04-28 | LEM International SA | Fluxgate current transducer |
| CN111999541A (en) * | 2020-09-10 | 2020-11-27 | 秦孝文 | Anti-magnetic disturbance integrated nondestructive current detection high-precision intelligent sensor probe |
| KR102435583B1 (en) * | 2021-01-19 | 2022-08-24 | 숭실대학교 산학협력단 | Magnetic field type current sensor manufactured with Carbon nanotube wire |
| CN112965448A (en) * | 2021-02-01 | 2021-06-15 | 青岛黄海学院 | Electric automatization management control system and device |
| WO2022249709A1 (en) * | 2021-05-24 | 2022-12-01 | 日置電機株式会社 | Impedance measurement device |
| WO2022249708A1 (en) * | 2021-05-24 | 2022-12-01 | 日置電機株式会社 | Signal injection device and impedance measurement device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06201731A (en) * | 1992-12-25 | 1994-07-22 | Nippondenso Co Ltd | Magnetic balance type current measuring device |
| JP2001033491A (en) * | 1999-07-16 | 2001-02-09 | Nippon Soken Inc | Current measuring apparatus |
| JP2011106890A (en) * | 2009-11-14 | 2011-06-02 | Mitsubishi Materials Corp | Current sensor device |
| CN102253262A (en) * | 2010-04-23 | 2011-11-23 | 株式会社田村制作所 | Current detector |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS475825Y1 (en) * | 1968-05-22 | 1972-02-29 | ||
| JPS59107270A (en) * | 1982-12-10 | 1984-06-21 | Alps Electric Co Ltd | Dc current measuring sensor |
| JPH1068744A (en) * | 1996-08-27 | 1998-03-10 | Sumitomo Special Metals Co Ltd | Direct current sensor |
| JP3142092U (en) * | 2008-03-19 | 2008-06-05 | 京都電機器株式会社 | Current detection circuit |
| JP2012225664A (en) * | 2011-04-15 | 2012-11-15 | Tdk Corp | Current sensor and current detection method |
-
2015
- 2015-03-30 JP JP2015068510A patent/JP6200445B2/en active Active
-
2016
- 2016-03-30 CN CN201610192052.2A patent/CN106018915B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06201731A (en) * | 1992-12-25 | 1994-07-22 | Nippondenso Co Ltd | Magnetic balance type current measuring device |
| JP2001033491A (en) * | 1999-07-16 | 2001-02-09 | Nippon Soken Inc | Current measuring apparatus |
| JP2011106890A (en) * | 2009-11-14 | 2011-06-02 | Mitsubishi Materials Corp | Current sensor device |
| CN102253262A (en) * | 2010-04-23 | 2011-11-23 | 株式会社田村制作所 | Current detector |
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