CN203930030U - Transient magnetic field differential transducer - Google Patents
Transient magnetic field differential transducer Download PDFInfo
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- CN203930030U CN203930030U CN201420345337.1U CN201420345337U CN203930030U CN 203930030 U CN203930030 U CN 203930030U CN 201420345337 U CN201420345337 U CN 201420345337U CN 203930030 U CN203930030 U CN 203930030U
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- magnetic field
- concentric cable
- electromagnetic screen
- open loop
- metal cylinder
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- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
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Abstract
The utility model is a kind of transient magnetic field differential transducer, comprises that a tours antenna support portion, an electromagnetic screen pipe and an electromagnetic screen output cassette are interconnected to form a housing.This transient magnetic field differential transducer comprises two concentric cable, an and open loop metal cylinder with a lateral opening, described two concentric cable are symmetrical arranged around this open loop metal cylinder, form half closed ring coil, this toroid winding and described open loop metal cylinder are arranged at and in described housing, form a sensing antenna.In described tours antenna support portion, the end points interval that described two concentric cable surround half closed ring coil and these two concentric cable symmetrically around described open loop metal cylinder arranges.The end points arranging in the space of described two concentric cable, the coaxial cable core of any one cable is connected by conduction with the screen layer of another one concentric cable.Two relative limits of the lateral opening of described open loop metal cylinder are respectively at the screen layer electrical connection of described two concentric cable.
Description
Technical field
The utility model relates to a kind of sensor, specially refers to a kind of transient magnetic field differential transducer.
Background technology
Along with scientific and technological progress, increasing electronic equipment can produce transient electromagnetic field, and this transient electromagnetic field can produce electromagnetic interference (EMI) to other electronic equipment, becomes interference source.Therefore, thus how to detect these interference sources and intensity thereof and take protection and shielding measure just to seem more and more urgent.Just can realize this goal and utilize transient magnetic field sensor to survey transient magnetic field.
According to different physical laws or physical phenomenon, such as magnetic induction, galvanomagnetic effect, nucleon motion, superconductive quantum interference, magnetic effect and magneto-optic effect etc., can produce the magnetic field sensor of different characteristics.They be applicable to the magnetic field intensity surveyed different, also have different sensitivity, Frequency Response and a suitable application area.This wherein can measure high frequency, high-intensity magnetic field with the transient magnetic field differential transducer that Faraday's electromagnetic induction law is made, and is comparatively ideal high power transient magnetic field sensor.
This sensor is the electric field that utilizes the magnetic field induction changing to go out to induct, and produces measurable hoop electric potential difference.Meeting inductive coil small size, in the situation of wavelength corresponding to the highest frequency of variation magnetic field, the average magnetic field rate of change in measured zone and the rate of change of magnetic approximately equal of its central point.So can indirectly measure the rate of change of magnetic at this regional center place with the induced voltage that induction necklace produces, more just can obtain the magnetic field intensity of this point by it is carried out to Integral Processing.But, because the electric field all existing in actual magnetic field environment can produce interference effect to the voltage signal of induction, the interference effect of electric field shielding how is become determine the key factor that transient magnetic field differential transducer whether can Measurement accuracy field signal.
Utility model content
For the impact on transient magnetic field differential transducer of the interference effect that overcomes electric field, the utility model provide a kind of with concentric cable the high power transient magnetic field differential transducer as magnetic field induction antenna.It can effectively avoid the impact of electric field on magnetic-field measurement, can also obtain higher bandwidth simultaneously.
The utility model solves the technical scheme that its technical matters adopts: a kind of transient magnetic field differential transducer, comprise a tours antenna support portion, one electromagnetic screen pipe and an electromagnetic screen output cassette are interconnected to form a housing, this transient magnetic field differential transducer further comprises two concentric cable, an and open loop metal cylinder with a lateral opening, described two concentric cable are symmetrical arranged around this open loop metal cylinder, form half closed ring coil, described open loop metal cylinder and described semiclosed annular coil are arranged in the housing of described tours antenna support portion and form a sensing antenna, the other end of these two concentric cable enters electromagnetic screen output cassette through described electromagnetic screen pipe, and separate and draw from described electromagnetic screen output cassette, in described tours antenna support portion, the end points interval that described two concentric cable surround half closed ring coil and these two concentric cable symmetrically arranges, the end points arranging in the space of described two concentric cable, the coaxial cable core of any one cable is connected by conduction with the screen layer of another one concentric cable, the lateral opening of described open loop metal cylinder has two limits that interval is relative, respectively at the screen layer electrical connection of described two concentric cable.
Compared with the prior art, the utility model high power transient magnetic field differential transducer has utilized the shielding action of concentric cable to overcome the interference of electric field dexterously, and the voltage signal inducing is transmitted out through concentric cable.Meanwhile, compare common small loop antenna, the output signal of this transient magnetic field differential transducer is in the time being connected with the checkout equipment such as oscillograph, and directly, with SMA connector, the decay and the anti-stop signal that effectively reduce signal distort.And the same with general passive device, there is not the upper limit of the magnetic field intensity of measurement in this sensor itself.
Brief description of the drawings
Fig. 1 is the structural representation of the utility model transient magnetic field differential transducer.
Fig. 2 is the decomposition chart of the utility model transient magnetic field differential transducer.
Fig. 3 is the structural representation of the antenna mounting portion of the utility model transient magnetic field differential transducer.
Fig. 4 is the structural representation of the lid of the antenna mounting portion of the utility model transient magnetic field differential transducer.
Fig. 5 is the electromagnetic screen adapter of this novel transient magnetic field differential transducer and the structural representation of electromagnetic screen pipe.
Fig. 6 is the structural representation of the electromagnetic screen output cassette of the utility model transient magnetic field differential transducer.
Fig. 7 is the decomposition texture schematic diagram of the electromagnetic screen output cassette of the utility model transient magnetic field differential transducer.
Fig. 8 is the schematic diagram of the fixed head between electromagnetic screen output cassette and the electromagnetic screen pipe of the utility model transient magnetic field differential transducer.
Fig. 9 is the distribution of current schematic diagram that concentric cable is made magnetic field antenna.
Figure 10 is the principle schematic of the sensing antenna of the utility model transient magnetic field differential transducer.
Figure 11 is this schematic diagram that uses the open loop metal cylinder of the sensing antenna of novel transient magnetic field differential transducer.
Figure 12 is the equivalent circuit diagram of the utility model transient magnetic field differential transducer.
Figure 13 is the simplification circuit of the utility model transient magnetic field differential transducer.
Figure 14 is the magnetic field sensor output voltage waveforms (oscilloscope display) of the utility model transient magnetic field differential transducer.
Figure 15 is waveform after the output signal integration of the utility model transient magnetic field differential transducer.
Figure 16 is the figure sensitivity calibration curve of the utility model transient magnetic field differential transducer.
Figure 17 is the output signal integration front and back waveform enlarged drawing of the utility model transient magnetic field differential transducer.
Main element symbol description
| Tours antenna support portion | 10 |
| Circle cap shell structure | 11 |
| Electromagnetic screen pipe | 20 |
| Ring screw | 22 |
| Electromagnetic screen output cassette | 30 |
| Electromagnetic screen adapter | 60 |
| Through hole | 62 |
| Metal fixed head | 70 |
| The first fixed orifice | 72 |
| The second fixed orifice | 74 |
| Sensing antenna | 80 |
| Transient magnetic field differential transducer | 100 |
| The first cylindrical part | 110 |
| Square groove | 112 |
| Extendable platform | 114 |
| Semiclosed annular platform | 115 |
| Breach | 116 |
| Hemi-closure space | 118 |
| The second cylindrical part | 119 |
| Opening | 120 |
| Lid | 130 |
| Enclosure space | 300 |
| Housing | 310 |
| Input hole | 312 |
| The 3rd fixed orifice | 313 |
| Delivery outlet | 316 |
| Concentric cable | 810 |
| Wire | 812 |
| Open loop metal cylinder | 820 |
Following embodiment further illustrates the utility model in connection with above-mentioned accompanying drawing.
Embodiment
Below in conjunction with drawings and Examples, the utility model is further elaborated, with reference to accompanying drawing.Should be understood that these embodiment are only not used in restriction scope of the present utility model for the utility model is described.In addition should be understood that and reading after the content of the utility model instruction, those skilled in the art can make various changes or modifications the utility model, and these equivalent form of values fall within the application's appended claims limited range equally.
Refer to Fig. 1 and Fig. 2, the utility model provides a kind of transient magnetic field differential transducer 100, and it comprises a tours antenna support portion 10, an electromagnetic screen pipe 20, an electromagnetic screen output cassette 30 and a sensing antenna 80.Described tours antenna support portion 10, described electromagnetic screen pipe 20, and described electromagnetic screen output cassette 30 is interconnected to form a shell structure.Described sensing antenna 80 comprises two concentric cable that are symmetrically set 810, and an open loop metal cylinder 820 with lateral opening is arranged among described shell structure.Interval, one end symmetry of described two concentric cable 810, surrounds half closed ring coil around described open loop metal cylinder 820 and is arranged at described tours antenna support portion 10.Only, at an end points of described two concentric cable 810, the cable core of any one concentric cable 810 is electrically connected by wire with the screen layer of another one cable.Two relative limits of lateral opening place of described open loop metal cylinder 820, are electrically connected with the electro-magnetic screen layer of described two concentric cable 810 respectively.The relatively described open loop metal cylinder 820 of described two concentric cable 810 is symmetrical arranged, and the interval of two concentric cable 810 end points is consistent with the lateral opening of described open loop metal cylinder 820.The other end of described two concentric cable 810 enters electromagnetic screen output cassette 30 through described electromagnetic screen pipe 20, and separates and draw from described electromagnetic screen output cassette 30.
Refer to Fig. 3, the structure that described tours antenna support portion 10 is hollow, for receiving and fixing the semiclosed annular coil that described two concentric cable 810 surround, and described open loop metal cylinder 820.This tours antenna support portion 10 is mutually fastened and forms by two round cap shell structures 11 with same structure.The side of this tours antenna support portion 10 has an opening 120, for drawing described two concentric cable 810.
Refer to Fig. 4, described round cap shell structure 11 comprises first cylindrical part 110 and second cylindrical part 119, this first cylindrical part 110 and a described hemi-closure space 118 of the second cylindrical part 119 common definition.This hemi-closure space 118 is for receiving described open loop metal cylinder 820, and the semiclosed annular coil that forms around two concentric cable 810 of this open loop metal cylinder 820 of symmetrical ring.Described the first cylindrical part 110 and the second cylindrical part 119 are interconnected to form described round cap shell structure 11.The slightly larger in diameter of described the first cylindrical part 110 is in the diameter sum of described concentric cable 810 and described open loop metal cylinder 820.The slightly larger in diameter of described the second cylindrical portion 119 is in the diameter of described open loop metal cylinder 820.The inside of described the first cylindrical part 110 has an annular semiclosed annular platform 115.This semiclosed annular platform 115 has 114, one square grooves 112 of two symmetrically arranged extendable platforms, and a breach 116.Described square groove 112 is communicated with two extendable platforms 114.Described breach 116 is symmetrical arranged with described square groove 112.Described two round cap shell structures 11 are formed with after relative fastening the in surface of semiclosed annular platform 115, form described tours antenna support portion 10, described two breach 116 that mutually fasten form an opening 120.
Described open loop metal cylinder 820 is made for the sheet metal with a thickness, and it can be that the materials such as gold, silver, copper, iron, aluminium are made.The shape of open loop metal cylinder is not limit, and can be can be square, rectangle, triangle, trapezoidal, circular or oval.In the present embodiment, this open loop metal cylinder 820 is cylinder, for copper becomes.Described concentric cable 810 comprises cable core, and around the electro-magnetic screen layer of cable core, has good electromagnetic shielding action for electromagnetic field.The half of described open loop metal cylinder 820 is arranged in the hemi-closure space 118 that a described round cap shell structure 11 defines, described two concentric cable 810 symmetrical rings are arranged at described semiclosed annular platform 115 around described open loop metal cylinder 820, form one as closed ring coil.Each concentric cable 810, from the square groove 112 of this semiclosed annular platform 115, is arranged along a described extendable platform 114, and is drawn from described breach 116.The end points of described two concentric cable 810 is oppositely arranged at described square groove 112 intervals.The cable core of any one concentric cable 810 is electrically connected by wire 812 in described square groove 112 with the screen layer of another one concentric cable 810, and this square groove 112 is for receiving described wire 812.The lateral opening of described open loop metal cylinder 820 is corresponding with the interval of the end points of described two concentric cable 810, and two relative limits of the lateral opening of described open loop metal cylinder 820 are electrically connected with the screen layer of described two concentric cable 810 respectively.
The fixed form of described two lids 130 is not limit, and can fix with cementing agent, also can adopt machinery fixing, as the mode of rivet or buckle, or also can form an entirety by integrated mode.
The shape that is appreciated that the first cylindrical part 110, the second cylindrical part 119 first and the semiclosed annular platform 115 thereof of above-mentioned tours antenna support portion 10 is not limit, and coordinates the shape of open loop metal cylinder 820 and size to select.The shape of this semiclosed annular platform 115 can be square, rectangle, triangle, trapezoidal, circular or oval.Make for insulating material this tours antenna support portion 10, its objective is in order to receive and to fix described open loop metal cylinder 820, and the semiclosed annular coil that forms of described two concentric cable 810.Because the sensitivity of magnetic field sensing antenna 80 is directly related with the area of its semiclosed annular coil, therefore in order to allow shape and the area of semiclosed annular coil remain unchanged, need certain stationary installation.And the magnetic field can not disturbing magnetic field antenna surveyed of this device, so the electrical characteristics of its material are had to certain requirement.Therefore, this tours antenna support portion 10 should be the insulating material that hardness is stronger and makes, as nylon 6, and nylon 66, epoxy plate, bakelite plate, teflon, organic glass etc.High-intensity insulating material can not be out of shape in the present embodiment, this tours antenna support portion 10 and semiclosed annular platform 115 thereof are circular, its material is teflon, because its specific inductive capacity is all very low in very wide frequency range, so the impact on electromagnetic field is very little, and physical strength is enough high.
Described two concentric cable 810, from the opening 120 of described tours antenna support portion 10 is drawn, enter in described electromagnetic screen pipe 20.One end of this electromagnetic screen pipe 20 is connected with the opening 120 of described tours antenna support portion 10.This electromagnetic screen pipe 20 has electromagnetic shielding action, can prevent that described concentric cable 810 is subject to the interference of external electromagnetic field, affects signal transmission.The two ends of electromagnetic screen pipe 20 can be provided with ring screw 22, for being connected with described tours antenna support portion 10 and electromagnetic screen output cassette 30.The material of described this electromagnetic screen pipe 20 is metal, as gold, silver, copper, iron, aluminium etc.Described concentric cable 810 extends along straight line in described electromagnetic screen pipe 20, and its extension line divides equally, the area at described semiclosed annular coil place.In one embodiment, this electromagnetic screen pipe 20 is aluminum pipe.
Refer to Fig. 5, this electromagnetic screen pipe 20 can be connected and fixed by an electromagnetic screen adapter 60.Electromagnetic screen adapter 60 has a through hole 62.Mate mutually with the opening 120 of described tours antenna support portion 10 one end of this electromagnetic screen adapter 60, thereby can be fixed on described tours antenna support portion 10.Other end through hole 62 inside surfaces of described electromagnetic screen adapter 60 can form internal thread, thereby mutually mate with the ring screw 22 of described electromagnetic screen pipe 20 one end, make one end of described electromagnetic screen pipe 20 be fixed on electromagnetic screen adapter 60.Thereby described two concentric cable 810 can enter this through hole 62 from the opening 120 of described tours antenna support portion 10, and enter in described electromagnetic screen pipe 20.The material of this electromagnetic screen adapter 60 is identical with described electromagnetic screen pipe 20.
Refer to Fig. 6 and Fig. 7, described electromagnetic screen output cassette 30 is made up of two housings 310 with same structure, and described two housings 310 are mutually fastened and define an enclosure space 300.There is an input hole 312 in a side of this electromagnetic screen output cassette 30, there are two delivery outlets 316 in a relative side of this electromagnetic screen output cassette 30.Described input hole 312 is fixed in one end of described electromagnetic screen pipe 20, is communicated with, thereby described two concentric cable 810 are introduced in electromagnetic screen output cassette 30, and draw respectively from described two delivery outlets 316 with described electromagnetic screen output cassette 30.Described electromagnetic screen pipe 20 is not limit with the fixed form of this electromagnetic screen output cassette 30, can fix with cementing agent, also can adopt machinery fixing, as the mode of rivet or buckle, or also can form an entirety by integrated mode with described electromagnetic screen output cassette 30.The material of this electromagnetic screen output cassette 30 is identical with described electromagnetic screen pipe 20.
Refer to Fig. 8, described electromagnetic screen pipe 20 can be fixed on described electromagnetic screen output cassette 30 and be formed with by a metal fixed head 70 side of input hole 312.This metal fixed head 70 has 4 the first fixed orifices 72, and 1 the second fixed orifice 74.The second fixed orifice 74 of this metal fixed head 70 is corresponding with the input hole 312 of described electromagnetic screen output cassette 30, and it is corresponding that 4 the first fixed orifices 72 and described electromagnetic screen output cassette 30 are formed with 4 the 3rd fixed orifices 313 in a side of input hole 312.One end that electromagnetic screen pipe 20 is formed with ring screw 22 can be fixed in the second fixed orifice 74 of described metal fixed head 70.Described metal fixed head 70 is screwed in described electromagnetic screen output cassette 30 and is formed with a side of input hole 312.Two delivery outlets 316 that are appreciated that this electromagnetic screen output cassette 30 can arrange respectively SMA interface, thereby described two concentric cable 810 can be directly connected with external instrument.
Refer to Fig. 9, because the electric conductivity of the metal screen layer of concentric cable 810 is fine, make its thickness d be greater than several skin depth δ, electromagnetic field of high frequency only exerts an influence to the skin of metal screen layer, and the inner wire of its internal layer and concentric cable 810 is not acted on.Like this, outer electric current and its internal layer electric current producing of the screen layer of the concentric cable 810 of participation magnetic field induction can mixed flow.In accompanying drawing 9,1,3 represent metal screen layer, and the dotted line in their regions represents the inside and outside two-layer separatrix of screen layer, the 2nd, inner wire.
with
the electric current of composition coaxial transmission line,
represent the electric current that changes of magnetic field induces, be also radiation current.
Accompanying drawing 10 has provided the schematic diagram of this sensing antenna 80, and it can be equivalent to two inductance compositions in parallel: the outer antenna of screen layer of an open loop metal tubular antenna and a concentric cable.For high frequency magnetic field, in accompanying drawing 10, the shield external layer A → C of concentric cable → B forms the magnetic field antenna of ring-type, obtains magnetic induction voltage U
aB(representing external shielding layer voltage), to having
(representing internal shield voltage), both are completely equal.Like this, A1 with
, B1 with
be respectively the voltage signal input end of left and right concentric cable 810, through symmetrical coaxial transmission line, output to E and F, and the output terminal forming with D.Refer to Figure 11, the height of this open loop metal cylinder 820 is h, and its diameter is D.
Suppose E and F, with their common port D(ground connection) connect respectively load ZL1 and ZL2, the equivalent electrical circuit of drawings attached 12.In Figure 12, Z1 and Z2 represent respectively the impedance that the metallic shield skin of the right and left concentric cable produces as magnetic field antenna.If the strict symmetry in left and right, Z1=Z2=0.5Z, Z is total impedance, comprises inductance and resistance.
When ring radius R is compared enough hour of the wavelength X min of measured magnetic field highest frequency component, General Requirements ring semi-perimeter
electrical length θ <10 °,
(1)
The now reactance of Z is far longer than resistance, and the approximate value of the induction reactance that available its inductance L C produces replaces Z.
LC approximate value:
(2)
And for the open loop cylindrical antenna making with metal good conductor, it inductance expression formula following (considering to change at its hoop directional current the induced voltage causing):
(3)
And its resistance is negligible by contrast.
In general, more suitable as long as the height h of cylinder aerial obtains, have
, due to their relation in parallel, have the hoop of cylindrical antenna inductance so the inductance L of total magnetic field antenna depends on,
.
Because screen layer does not have electric current diametrically, thus in accompanying drawing 12 ectonexine equipotentiality diametrically.Because CA1(or C
) the screen layer skin of concentric cable of section is magnetic field antenna, so not equipotentiality of this section of screen layer, this understanding for voltage signal transmission in accompanying drawing 11 is very important.And CE(or CD) coaxial cable shielding layer of section is equipotentiality, all ground connection.By the screen layer internal layer of concentric cable and the transmission line of inner wire composition, obtain again
In like manner also have,
Obtain output voltage,
(4)
Therefore the magnetic field to satisfied (1) expression formula,
.If also have Z
l1=Z
l2=Z
0, Z
0for the characteristic impedance of concentric cable.If load matched, just like the simplification circuit of accompanying drawing 13.
Based on accompanying drawing 13, output voltage expression formula is carried out to Fourier analysis as follows:
By exporting expression formula:
Obtain transport function
Can prove, if
(5)
?
(6)
Transport function can be reduced to simultaneously:
Right
fourier's inversion obtains:
(7)
So output signal U (t) is that input magnetic field B (t) postpones the differential after 2L/Z0, amplitude 2A is exactly sensitivity.
All that the outer field skin effect of coaxial cable shielding layer makes magnetic field cannot enter the inner wire of concentric cable about the prerequisite of the analysis of modified Mobius ring magnetic field sensor principle of work above.And for the very low frequency (VLF) composition in magnetic field, skin effect is not remarkable, magnetic field can enter inner wire through the metal screen layer of concentric cable, and analysis meeting is different.But know that with reference to accompanying drawing 1 now modified Mobius ring magnetic field antenna deteriorates to two simple conductor loops, i.e. B → C → A → B1 → A1 → B, then consider the situation that in (6), ω goes to zero, export expression formula unified with (7).
Due to no matter be high frequency or low-frequency current field, concentric cable metal screen layer can both be shielded effectively, so know that with reference to accompanying drawing 1 electric field is the circle of a sealing to the reach of modified Mobius ring magnetic field antenna just, if electric field frequency also meets the constraint formula of (1), electric field just can not measured by disturbing magnetic field.
In the time that magnetic field sensor designs, topmost two indexs are its bandwidth and sensitivity, and for high power transient magnetic field sensor, first will consider whether the bandwidth of magnetic field sensor satisfies the demand, and allow on this basis the sensitivity of sensor more high better.Provide below and require the specific design flow process of sensor bandwidth more than 400MHz:
Know by principle analysis above, modified Mobius ring do magnetic field antenna in the time of bandwidth Design, need to consider below bandwidth constraint relational expression,
(7)
(8)
Like this, by selecting rational R, r and Z
0(general 50 Ω), just can design the magnetic field sensor of respective bandwidth.Wherein r, the selection that is exactly the external radius of concentric cable metal screen layer need to be considered the actual size having.
Such as selecting the concentric cable that the model of Harbour Industries product is SS405, its metallic shield outer diameter D=2.11mm, r=1.05mm, characteristic impedance is 50 Ω; Design R=7.75mm, axis height h=45mm, the bandwidth BW=f0=453.07MHz of estimation design, sensitivity S=2A=377mm
2.
The transient magnetic field differential transducer 100 that can provide by standard transverse electromagnetic wave generating means gtem cell calibration the utility model is mainly sensitivity and the bandwidth of calibrating sensors.In experiment, add photo transmission system in transient magnetic field differential transducer 100 rear ends so that signal long-distance transmission is unattenuated.
Main result refers to Figure 14 to Figure 17.Figure 14 is to gtem cell input end (that provide in figure is 2kV), the voltage signal that sensor is measured in effective coverage in gtem cell the square wave pulse voltage of different amplitudes.Figure 15 is waveform before and after output signal integration, and wherein inputting square-wave voltage amplitude is 2kV, and pulsewidth is 50ns, realizes the integration operation of output voltage signal by the method for numerical integration.Figure 16 is the figure sensitivity calibration curve of the utility model transient magnetic field differential transducer, and wherein linearly dependent coefficient R=0.9963, need to be converted into the magnetic field intensity in gtem cell input voltage, and expression formula is
, wherein U represents to input square-wave voltage amplitude, and h is the vertical height of sensor measurement point in gtem cell.Figure 17 is the output signal integration front and back waveform enlarged drawing of the utility model transient magnetic field differential transducer.In Figure 17, the rising time of integrated waveform
be about 0.68ns, according to
the bandwidth that can judge sensor is about 514MHz.The 453MHz estimating when this value is greater than design, the bandwidth of magnetic field sensor should, more than 400MHz, reach re-set target.
Compare the magnetic field differential transducer that common small loop antenna forms, the utility model high power transient magnetic field differential transducer has utilized the shielding action of concentric cable to overcome the interference of electric field dexterously, and the voltage signal inducing is transmitted out through concentric cable.Meanwhile, compare common small loop antenna, the output signal of this transient magnetic field differential transducer is in the time being connected with the checkout equipment such as oscillograph, and directly, with SMA connector, the decay and the anti-stop signal that effectively reduce signal distort.And the same with general passive device, there is not the upper limit of the magnetic field intensity of measurement in this sensor itself.
Claims (10)
1. a transient magnetic field differential transducer, comprise a tours antenna support portion, one electromagnetic screen pipe and an electromagnetic screen output cassette are interconnected to form a housing, it is characterized in that, this transient magnetic field differential transducer further comprises two concentric cable, an and open loop metal cylinder with a lateral opening, described two concentric cable are symmetrical arranged around this open loop metal cylinder, form half closed ring coil, described open loop metal cylinder and described semiclosed annular coil are arranged at and in described tours antenna support portion, form a sensing antenna, the other end of these two concentric cable enters electromagnetic screen output cassette through described electromagnetic screen pipe, and separate and draw from described electromagnetic screen output cassette, in described tours antenna support portion, the end points interval that described two concentric cable surround half closed ring coil and these two concentric cable symmetrically arranges, the end points arranging in the space of described two concentric cable, the coaxial cable core of any one cable is connected by conduction with the screen layer of another one concentric cable, the lateral opening of described open loop metal cylinder has two limits that interval is relative, respectively at the screen layer electrical connection of described two concentric cable.
2. transient magnetic field differential transducer as claimed in claim 1, it is characterized in that, described tours antenna support portion comprises the round cap shell structure of two of symmetrical fastening, each round cap shell structure comprises that first cylindrical part and second cylindrical part interconnect, and hemi-closure space of the common definition of this first cylindrical part and this second cylindrical part is for receiving two semiclosed annular coils that concentric cable symmetrical ring forms around this open loop metal cylinder described in described open loop metal cylinder machine.
3. transient magnetic field differential transducer as claimed in claim 2, it is characterized in that, the inside of described the first cylindrical part has an annular semiclosed annular platform, this semiclosed annular platform has two symmetrically arranged extendable platforms, a square groove and a breach, after the fastening of the first cylindrical part of described two round cap shell structures, the breach of the semiclosed annular platform of the lid of described two the first cylindrical part forms an opening.
4. transient magnetic field differential transducer as claimed in claim 3, it is characterized in that, the half of described open loop metal cylinder is arranged in the hemi-closure space of described round cap shell structure definition, described two concentric cable symmetrical rings are arranged at described semiclosed annular platform around described open loop metal cylinder, closed ring coil as forming one, draws the described opening that the other end of described two concentric cable forms from the breach of the semi-closed ring connected in star of described two lids.
5. transient magnetic field differential transducer as claimed in claim 4, it is characterized in that, the other end of described two concentric cable is drawn and is entered described electromagnetic screen pipe from described opening, described two concentric cable are parallel to each other in described electromagnetic screen pipe inside, and the extended line of described electromagnetic screen tube hub axle is divided described semiclosed annular coil equally, and the center of this semiclosed annular coil of mistake.
6. transient magnetic field differential transducer as claimed in claim 5, it is characterized in that, further comprise an electromagnetic screen adapter, this electromagnetic screen adapter mates mutually with one end of described opening and described electromagnetic screen pipe, one end of described electromagnetic screen pipe and described tours antenna support portion are fixed to composition enclosed construction.
7. transient magnetic field differential transducer as claimed in claim 6, it is characterized in that, described electromagnetic screen output cassette has relative first end and the second end, described first end has an input hole, described the second end has two delivery outlets, the other end of described electromagnetic screen pipe is fixed on the first end of described electromagnetic screen output cassette, and form enclosed construction with described electromagnetic screen input cartridge, described two concentric cable enter described electromagnetic screen output cassette by described input hole, and draw from described two delivery outlets respectively.
8. transient magnetic field differential transducer as claimed in claim 7, it is characterized in that, further comprise that two SMA connectors are fixed on described two delivery outlets, the part that described two concentric cable are drawn at the delivery outlet of described shielding input cartridge is electrically connected with described SMA connector.
9. transient magnetic field differential transducer as claimed in claim 1, is characterized in that, described semi-enclosed toroidal square, rectangle, triangle, trapezoidal, circular or oval of being shaped as.
10. transient magnetic field differential transducer as claimed in claim 1, is characterized in that, described open loop metal cylinder is that gold, silver, copper, iron or aluminium are made.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420345337.1U CN203930030U (en) | 2014-06-26 | 2014-06-26 | Transient magnetic field differential transducer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420345337.1U CN203930030U (en) | 2014-06-26 | 2014-06-26 | Transient magnetic field differential transducer |
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| Publication Number | Publication Date |
|---|---|
| CN203930030U true CN203930030U (en) | 2014-11-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420345337.1U Expired - Lifetime CN203930030U (en) | 2014-06-26 | 2014-06-26 | Transient magnetic field differential transducer |
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| CN (1) | CN203930030U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105161817A (en) * | 2015-09-29 | 2015-12-16 | 国家电网公司 | Oscillator replacing structure of pulse field strength probe |
| CN110531285A (en) * | 2019-09-26 | 2019-12-03 | 清华大学 | A kind of Multiple level transient magnetic field sensor |
-
2014
- 2014-06-26 CN CN201420345337.1U patent/CN203930030U/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105161817A (en) * | 2015-09-29 | 2015-12-16 | 国家电网公司 | Oscillator replacing structure of pulse field strength probe |
| CN110531285A (en) * | 2019-09-26 | 2019-12-03 | 清华大学 | A kind of Multiple level transient magnetic field sensor |
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Granted publication date: 20141105 |