CN111965715A - Double-emitting-coil transient electromagnetic combination device - Google Patents
Double-emitting-coil transient electromagnetic combination device Download PDFInfo
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- 238000000034 method Methods 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 4
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V3/00—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation
- G01V3/08—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices
- G01V3/10—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils
- G01V3/104—Electric or magnetic prospecting or detecting; Measuring magnetic field characteristics of the earth, e.g. declination, deviation operating with magnetic or electric fields produced or modified by objects or geological structures or by detecting devices using induction coils using several coupled or uncoupled coils
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Abstract
The invention relates to a transient electromagnetic combination device with double transmitting coils, which comprises a positive transmitting coil, a negative transmitting coil, a receiving coil, a transmitter and a receiver, wherein the positive transmitting coil is connected with the negative transmitting coil; the positive transmitting coil and the negative transmitting coil are electrically connected with the transmitter, and the receiving coil is electrically connected with the receiver; the receiving coil is positioned in the positive transmitting coil, and the reverse transmitting coil is positioned in the receiving coil; when the transmitter supplies power to the positive transmitting coil and the negative transmitting coil, the directions of currents in the positive transmitting coil and the negative transmitting coil are opposite, and magnetic flux generated by the positive transmitting coil in the receiving coil is equal to the magnetic flux generated by the negative transmitting coil in the receiving coil in magnitude and opposite to each other. In the invention, the total magnetic flux generated by the forward transmitting coil and the reverse transmitting coil in the receiving coil is zero, so that the aliasing phenomenon of a primary field and a secondary field of a conventional receiving coil can be eliminated, the influence of mutual inductance is reduced, and the observed transient electromagnetic signal conforms to the actual rule.
Description
Technical Field
The invention relates to transient electromagnetic equipment, in particular to a transient electromagnetic combination device with double transmitting coils.
Background
Transient Electromagnetic Methods (TEM), also known as time domain Electromagnetic Methods, are commonly used physical exploration Methods, and the working principle of the method is to introduce varying currents into a ground lead or an ungrounded return line, transmit a primary field to a detection area, and generate an induced current in a target geologic body under the action of the primary field, and then generate a secondary field. In actual practice, the secondary field is often observed at the primary field gap time. The method is mainly applied to the fields of engineering geological exploration, metal mine exploration, coal mine exploration and the like. The existing coils mostly adopt overlapping loop coils, mutual inductance is strong, especially in the early stage, induced electromotive force and secondary field electromotive force are overlapped, and a measurement curve does not accord with the electromagnetic law of a secondary field, so that the actual use effect does not accord with the actual geological condition.
Disclosure of Invention
The invention aims to solve the technical problem of providing a transient electromagnetic combination device of a double-emitting coil, which can eliminate the aliasing phenomenon of a primary field and a secondary field of a conventional receiving coil, reduce the mutual inductance influence and enable the observed transient electromagnetic signal to accord with the actual electromagnetic law.
The technical scheme for solving the technical problems is as follows: a double-emitting-coil transient electromagnetic combination device comprises a positive emitting coil, a negative emitting coil, a receiving coil, a transmitter and a receiver; the positive transmitting coil and the negative transmitting coil are electrically connected with the transmitter, and the receiving coil is electrically connected with the receiver; the receiving coil is positioned in the positive transmitting coil, and the reverse transmitting coil is positioned in the receiving coil; when the transmitter supplies power to the positive transmitting coil and the reverse transmitting coil, the directions of currents in the positive transmitting coil and the reverse transmitting coil are opposite, and the magnetic flux generated by the positive transmitting coil in the receiving coil is equal to the magnetic flux generated by the reverse transmitting coil in the receiving coil in magnitude and opposite to each other.
The invention has the beneficial effects that: in the transient electromagnetic combination device of the double-emitting coil, the total magnetic flux generated by the positive emitting coil and the negative emitting coil in the receiving coil is zero, so that the aliasing phenomenon of a primary field and a secondary field of a conventional receiving coil can be eliminated, the influence of mutual inductance is reduced, and the observed transient electromagnetic signal conforms to the actual rule; in addition, the receiving coil is arranged between the positive transmitting coil and the reverse transmitting coil, compared with a device in which the receiving coil is arranged at the innermost circle, the area of the receiving coil can be effectively increased, the intensity of induced voltage is improved, when the reverse transmitting coil is arranged at the innermost circle, the area is smaller, a reverse primary field generated in a detection area is also smaller, and therefore the total primary field intensity of the detection area is improved, and compared with other detection devices using a compensation coil, the device has a higher signal-to-noise ratio.
On the basis of the technical scheme, the invention can be further improved as follows.
Further, the forward transmitting coil, the reverse transmitting coil and the receiving coil are coplanar, and the forward transmitting coil surrounds the receiving coil, and the receiving coil surrounds the reverse transmitting coil.
The beneficial effect of adopting the further scheme is that: just transmitting coil, anti-transmitting coil and receiving coil coplane set up, and space utilization is higher, and the volume is littleer more light, is fit for using in narrow and small spaces such as mine tunnel.
Further, the forward transmitting coil, the backward transmitting coil and the receiving coil are not coplanar, and the projections of the forward transmitting coil, the backward transmitting coil and the receiving coil in the vertical direction still surround each other, and the projection of the forward transmitting coil surrounds the projection of the receiving coil, and the projection of the receiving coil surrounds the projection of the backward transmitting coil.
Further, the forward transmitting coil, the backward transmitting coil and the receiving coil are all coils with adjustable circumferences.
Further, the forward transmitting coil, the reverse transmitting coil and the receiving coil are coils with adjustable turns.
Further, the forward transmitting coil, the reverse transmitting coil and the receiving coil are closed coils with the same or different shapes.
The beneficial effect of adopting the further scheme is that: the circumferences, the shapes and the turns of the positive transmitting coil, the negative transmitting coil and the receiving coil are adjustable, and the exploration requirements of different depths can be met.
Further, the axes of the forward transmitting coil, the backward transmitting coil and the receiving coil are the same.
Further, the axes of the forward transmitting coil, the backward transmitting coil and the receiving coil are different.
The beneficial effect of adopting the further scheme is that: in the invention, the positive transmitting coil, the reverse transmitting coil and the receiving coil only need to be mutually surrounded without sharing an axis, can be freely arranged, and can meet the requirement of actual work only by ensuring that the current directions in the positive transmitting coil and the reverse transmitting coil are opposite and the total magnetic flux in the receiving coil is zero or approximately zero.
Drawings
FIG. 1 is a schematic diagram of a first structure of a dual-emitting-coil transient electromagnetic assembly according to the present invention;
FIG. 2 is a schematic diagram of a second structure of a dual-emitting-coil transient electromagnetic assembly according to the present invention;
FIG. 3 is a schematic diagram of a third structure of a dual-emitting-coil transient electromagnetic assembly according to the present invention;
FIG. 4 is a schematic diagram of a fourth structure of a dual-emitting-coil transient electromagnetic assembly according to the present invention;
FIG. 5 is a schematic diagram of a fifth structure of a dual-emitting-coil transient electromagnetic assembly according to the present invention;
FIG. 6 is a diagram illustrating a sixth configuration of a dual-coil transient electromagnetic assembly according to the present invention;
FIG. 7 is a graph of measured data before and after compensation.
In the drawings, the components represented by the respective reference numerals are listed below:
1. a reverse transmitting coil, 2, a receiving coil, 3 and a positive transmitting coil.
Detailed Description
The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.
As shown in fig. 1 to 6, a double-emitting-coil transient electromagnetic combination device comprises a positive emitting coil 3, a negative emitting coil 1, a receiving coil 2, a transmitter and a receiver; the positive transmitting coil 3 and the negative transmitting coil 1 are both electrically connected with the transmitter, and the receiving coil 2 is electrically connected with the receiver; the receiving coil 2 is positioned in the positive transmitting coil 3, and the reverse transmitting coil 1 is positioned in the receiving coil 2; when the transmitter supplies power to the forward transmitting coil 3 and the reverse transmitting coil 1, the directions of currents in the forward transmitting coil 3 and the reverse transmitting coil 1 are opposite, and the magnetic flux generated by the forward transmitting coil 3 in the receiving coil 2 is equal to and opposite to the magnetic flux generated by the reverse transmitting coil 1 in the receiving coil 2.
In this particular embodiment:
preferably, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are coplanar, and the forward transmitting coil 3 surrounds the receiving coil 2 and the receiving coil 2 surrounds the reverse transmitting coil 1. Just transmitting coil 3, anti-transmitting coil 1 and receiving coil 2 coplane set up, and space utilization is higher, and the volume is littleer more light, is fit for using in narrow and small spaces such as mine tunnel.
Preferably, the forward transmitting coil 3, the backward transmitting coil 1 and the receiving coil 2 are not coplanar, and the projections of the forward transmitting coil 3, the backward transmitting coil 1 and the receiving coil 2 in the vertical direction still surround each other, and the projection of the forward transmitting coil 3 surrounds the projection of the receiving coil 2, and the projection of the receiving coil 2 surrounds the projection of the backward transmitting coil 1.
Preferably, the positive transmitting coil 3, the negative transmitting coil 1 and the receiving coil 2 are all adjustable-circumference coils.
Preferably, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are coils with adjustable turns.
Preferably, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are closed coils with the same or different shapes. In fig. 1, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are all circular; in fig. 2, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are all square; in fig. 3, the forward transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 are all regular hexagons; in fig. 4, the forward transmitter coil 3 and the receiver coil 2 are square, and the reverse transmitter coil 1 is circular; in fig. 5, the forward transmitting coil 3 is square, and the receiving coil 2 and the reverse transmitting coil 1 are circular; in fig. 6, the forward transmitting coil 3 and the reverse transmitting coil 1 are square, and the receiving coil 2 is circular; in addition, the shapes of the forward transmission coil 3, the reverse transmission coil 1, and the reception coil 2 may be different from each other. The circumferences of the positive transmitting coil 3, the negative transmitting coil 1 and the receiving coil 2 are adjustable, the shapes and the turns of the positive transmitting coil, the negative transmitting coil and the receiving coil are adjustable, and the exploration requirements of different depths can be met.
Preferably, the axes of the forward transmission coil 3, the reverse transmission coil 1 and the receiving coil 2 are the same.
Preferably, the axes of the forward transmitting coil 3, the backward transmitting coil 1 and the receiving coil 2 are different. In the invention, the positive transmitting coil 3, the reverse transmitting coil 1 and the receiving coil 2 only need to be mutually surrounded without sharing an axis, can be freely arranged, and can meet the requirement of actual work only by ensuring that the current directions in the positive transmitting coil 3 and the reverse transmitting coil 1 are opposite, and the total magnetic flux in the receiving coil 2 is zero or approximately zero.
In the embodiment, the positive transmitting coil 3 is composed of n3Formed by winding a coil of turns having an area S3A circumference of C3The current is I3(ii) a The counter-emitting coil 1 is composed of n1Formed by winding a coil of turns having an area S1A circumference of C1The current is I1(ii) a The receiving coil 2 is composed of n2Formed by winding a coil of turns having an area S2。
And (3) deducing the magnetic induction intensity of any point in the receiving coil according to the Biot-Savart law:
wherein, mu0Is the vacuum permeability, dk is the line element vector on the transmitting coil; l is the vector distance between the integration point in the plane of the receiving coil and the vector dk of the line element of the transmitting coil, and n is the number of turns of the transmitting coil.
The magnetic flux generated by the positive transmitting coil 3 in the receiving coil 2 is:
the magnetic flux generated by the counter-transmitting coil 1 in the receiving coil 2 is:
the primary field induced voltage generated by the receiving coil 2 is:
in order to make the primary field induced voltage of the receiving coil 2 about 0, it is necessary to ensure that the rate of change of the primary field inside the receiving coil 2 is 0 or about 0, i.e. there are:
the total magnetic flux in the receiving coil 2 is then equal to 0 (or approximately equal to 0), that is to say the total magnetic field in the receiving coil 2 is approximately equal to 0. Therefore, the device can adjust the current passing through the forward transmitting coil 3 and the reverse transmitting coil 1, the number of turns and the perimeter, and the area of the receiving coil 2 to achieve the purpose that the total magnetic field is equal to 0 or approximately equal to 0.
Fig. 7 is a graph of measured data before and after compensation, and in fig. 7, one beam of curve located on the upper right is measured data before compensation, and one beam of curve located on the lower left is measured data after compensation.
According to the invention, by adjusting the areas, the number of turns and the current of the receiving coil 2, the forward transmitting coil 3 and the backward transmitting coil 1, the magnetic flux of the primary field on the receiving coil 2 can be counteracted, and the aliasing phenomenon of the primary field and the secondary field of the conventional receiving coil is eliminated; because the aliasing phenomenon of the primary field and the secondary field of the conventional receiving coil is eliminated, the dynamic range of the received signal is reduced, and the problem of difficulty in receiving weak secondary signals is solved; meanwhile, the whole working device is smaller and more compact and is convenient to use; need not to adjust after using the fixed bolster, measuring effect is accurate reliable.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (8)
1. The utility model provides a two sending out radial coil transient electromagnetism composite set which characterized in that: the device comprises a positive transmitting coil, a negative transmitting coil, a receiving coil, a transmitter and a receiver; the positive transmitting coil and the negative transmitting coil are electrically connected with the transmitter, and the receiving coil is electrically connected with the receiver; the receiving coil is positioned in the positive transmitting coil, and the reverse transmitting coil is positioned in the receiving coil; when the transmitter supplies power to the positive transmitting coil and the reverse transmitting coil, the directions of currents in the positive transmitting coil and the reverse transmitting coil are opposite, and the magnetic flux generated by the positive transmitting coil in the receiving coil is equal to the magnetic flux generated by the reverse transmitting coil in the receiving coil in magnitude and opposite to each other.
2. The dual-emitting-coil transient electromagnetic assembly of claim 1, wherein: the positive transmitting coil, the reverse transmitting coil and the receiving coil are coplanar, the positive transmitting coil surrounds the receiving coil, and the receiving coil surrounds the reverse transmitting coil.
3. The dual-emitting-coil transient electromagnetic assembly of claim 1, wherein: the forward transmitting coil, the backward transmitting coil and the receiving coil are not coplanar, projections of the forward transmitting coil, the backward transmitting coil and the receiving coil in the vertical direction still surround each other, the projection of the forward transmitting coil surrounds the projection of the receiving coil, and the projection of the receiving coil surrounds the projection of the backward transmitting coil.
4. A dual-emitter coil transient electromagnetic assembly as claimed in any one of claims 1 to 3, wherein: the positive transmitting coil, the negative transmitting coil and the receiving coil are all adjustable-circumference coils.
5. A dual-emitter coil transient electromagnetic assembly as claimed in any one of claims 1 to 3, wherein: the positive transmitting coil, the negative transmitting coil and the receiving coil are coils with adjustable turns.
6. A dual-emitter coil transient electromagnetic assembly as claimed in any one of claims 1 to 3, wherein: the positive transmitting coil, the negative transmitting coil and the receiving coil are closed coils with the same or different shapes.
7. A dual-emitter coil transient electromagnetic assembly as claimed in any one of claims 1 to 3, wherein: the axes of the forward transmitting coil, the backward transmitting coil and the receiving coil are the same.
8. A dual-emitter coil transient electromagnetic assembly as claimed in any one of claims 1 to 3, wherein: the axes of the forward transmitting coil, the backward transmitting coil and the receiving coil are different.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010806755.6A CN111965715A (en) | 2020-08-12 | 2020-08-12 | Double-emitting-coil transient electromagnetic combination device |
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| CN202010806755.6A CN111965715A (en) | 2020-08-12 | 2020-08-12 | Double-emitting-coil transient electromagnetic combination device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112415609A (en) * | 2020-12-14 | 2021-02-26 | 安徽国科骄辉科技有限公司 | Double-emission zero-magnetic-flux transient electromagnetic detection device |
| CN114814957A (en) * | 2022-04-15 | 2022-07-29 | 吉林大学 | A Plane Gradient Measurement Method Based on Transient Electromagnetic Method |
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| CN108008451A (en) * | 2018-01-30 | 2018-05-08 | 安徽惠洲地质安全研究院股份有限公司 | A kind of transient electromagnetic detection device and the method for eliminating inductive interferences |
| CN110488357A (en) * | 2019-07-08 | 2019-11-22 | 吉林大学 | A kind of separate type Transient electromagnetic measure compensation system and control method based on SQUID |
| CN111290029A (en) * | 2020-03-27 | 2020-06-16 | 吉林大学 | Towed electromagnetic device with non-coplanar Bucking compensation and manufacturing method |
| CN212647014U (en) * | 2020-08-12 | 2021-03-02 | 武汉地大华睿地学技术有限公司 | Double-emitting-coil transient electromagnetic combination device |
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2020
- 2020-08-12 CN CN202010806755.6A patent/CN111965715A/en active Pending
Patent Citations (4)
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| CN108008451A (en) * | 2018-01-30 | 2018-05-08 | 安徽惠洲地质安全研究院股份有限公司 | A kind of transient electromagnetic detection device and the method for eliminating inductive interferences |
| CN110488357A (en) * | 2019-07-08 | 2019-11-22 | 吉林大学 | A kind of separate type Transient electromagnetic measure compensation system and control method based on SQUID |
| CN111290029A (en) * | 2020-03-27 | 2020-06-16 | 吉林大学 | Towed electromagnetic device with non-coplanar Bucking compensation and manufacturing method |
| CN212647014U (en) * | 2020-08-12 | 2021-03-02 | 武汉地大华睿地学技术有限公司 | Double-emitting-coil transient electromagnetic combination device |
Non-Patent Citations (1)
| Title |
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| ZHENZHU XI 等: "Opposing-coils transient electromagnetic method focused near-surface resolution", 《GEOPHYSICS》, vol. 8, no. 5, 7 July 2016 (2016-07-07), pages 279 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112415609A (en) * | 2020-12-14 | 2021-02-26 | 安徽国科骄辉科技有限公司 | Double-emission zero-magnetic-flux transient electromagnetic detection device |
| CN114814957A (en) * | 2022-04-15 | 2022-07-29 | 吉林大学 | A Plane Gradient Measurement Method Based on Transient Electromagnetic Method |
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