A transmitting coil group and a transient electromagnetic exploration device

Abstract

A transmitting coil group and a transient electromagnetic exploration device. The transmitting coil group includes: N transmitting coils, where N is an odd number and N is greater than or equal to 3. The transmitting coil located at the central axis position of the N transmitting coils is horizontally arranged, and the N - 1 transmitting coils at non - central axis positions are symmetrically arranged on both sides of the central axis position, and the transmitting coils on either side are arranged alternately in the vertical and horizontal directions; all N transmitting coils are used to generate a magnetic field after being connected to a transmitter; taking the magnetic field direction of the transmitting coil at the central axis position as the starting direction, the magnetic north directions of multiple transmitting coils on either side of the central axis position are all cycled clockwise or counterclockwise, and the cycling directions on both sides are opposite. This makes the magnetic flux of the primary field generated by the transmitting coils close to 0 through the receiving unit, and can also eliminate the magnetic flux of the turn - off induced magnetic field collected by the receiving unit during the process of turning off the current of the transmitting coils to generate the induced magnetic field, thereby improving the signal - to - noise ratio of the transient electromagnetic detection signal.

Description

Technical Field

[0001] The present invention belongs to the field of geophysical exploration, and particularly relates to a transmitting coil group and a transient electromagnetic exploration device. Background Art

[0002] The transient electromagnetic detection technology is one of the important detection methods in the field of geophysical exploration, and is widely used in groundwater detection, underground metal detection, coal seam detection, underground cavity detection, seismic hazard assessment, archaeology and engineering exploration. The transient electromagnetic exploration technology uses the magnetic field generated by the current in the transmitting antenna (referred to as the primary magnetic field), and emits the primary magnetic field to the detection area. The detection target will have an electromagnetic induction phenomenon, thus generating eddy currents. When the current in the transmitting antenna is turned off, the magnetic field generated by the eddy currents in the target body (i.e., the secondary magnetic field) is measured to obtain abnormal information in the detection area. However, the primary magnetic field generated by the transmitting antenna has a greater impact on the receiving antenna, and the mutual inductance generated between the transmitting antenna and the receiving antenna during the turn-off process will also cause a certain impact. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, the present invention provides a transmitting coil group, and the transmitting coil group solves the problems of the influence of the primary magnetic field generated by the transmitting antenna on the receiving antenna and the influence of the mutual inductance generated during the turn-off process. The present invention also provides a transient electromagnetic exploration device.

[0004] The transmitting coil group according to the first aspect embodiment of the present invention includes:

[0005] N transmitting coils, where N is an odd number and N is greater than or equal to 3. The transmitting coil located at the central axis position of the N transmitting coils is horizontally arranged, and the N - 1 transmitting coils at non - central axis positions are symmetrically arranged on both sides of the central axis position, and the transmitting coils on either side are arranged alternately in the vertical and horizontal directions; the N transmitting coils are used to generate a magnetic field after being connected to a transmitter; taking the magnetic field direction of the transmitting coil at the central axis position as the starting direction, the magnetic north directions of the multiple transmitting coils on either side of the central axis position all cycle clockwise or counterclockwise, and the cycle directions on both sides are opposite.

[0006] The transmitting coil group according to the embodiments of the present invention has at least the following technical effects: Any odd number of transmitting coils, with a minimum of 3, are horizontally arranged with the transmitting coil located at the central axis position as the starting point, and the remaining transmitting coils are symmetrically arranged on both the left and right sides, and are arranged in an alternating vertical and horizontal manner. After each coil is connected to the transmitter and energized, the direction of the magnetic north pole changes regularly. The magnetic north pole directions of multiple transmitting coils on either side of the central axis position all cycle clockwise or counterclockwise, ensuring that the cycle directions on both sides are opposite. The magnetic north pole direction of the coil at the central axis position is to the left or right. According to this specific arrangement of the transmitting coils, not only does the magnetic flux of the primary field generated by the transmitting coils passing through the receiving unit approach 0, achieving the elimination of the influence of the primary field, but also during the process of turning off the induced magnetic field generated by the current of the transmitting coil, the magnetic flux of the turned-off induced magnetic field collected by the receiving unit can be eliminated, ensuring that the receiving unit collects the secondary field signal of the underground medium, thereby improving the signal-to-noise ratio of the transient electromagnetic detection signal. In addition, due to the specific arrangement of the transmitting coils changing the magnetic field distribution, weakening the magnetic field above and enhancing the magnetic field intensity below, the intensity of the primary field generated by the transmitting coils of the present invention is also greatly improved.

[0007] According to some embodiments of the present invention, the winding radius of each turn of each of the transmitting coils is equal, or increases or decreases in sequence.

[0008] According to some embodiments of the present invention, each of the transmitting coils has the same length.

[0009] According to some embodiments of the present invention, the diameters and numbers of turns of every two transmitting coils symmetric about the central axis position are the same.

[0010] According to some embodiments of the present invention, the transmitting coils are made of paramagnetic medium material or high-permeability magnetic medium material.

[0011] According to some embodiments of the present invention, the N transmitting coils are connected in parallel with the transmitter.

[0012] According to some embodiments of the present invention, the N transmitting coils are connected in series, and the series structure formed by the N transmitting coils is connected to the transmitter.

[0013] The transient electromagnetic exploration device according to the second aspect embodiment of the present invention includes:

[0014] The transmitting coil group according to any one of the first aspect;

[0015] A transmitter for generating a magnetic field in the N transmitting coils;

[0016] A receiving unit, the receiving plane of the receiving unit is orthogonal to the central axis of the transmitting coil group and is located on the side with weak magnetic force of the transmitting coil group, and the receiving unit is used to collect the magnetic flux in the vertical direction;

[0017] A receiver, electrically connected to the receiving unit.

[0018] The transient electromagnetic exploration device according to the embodiment of the present invention has at least the following technical effects: applying the transmitting coil group described in the first aspect, any odd number of transmitting coils with at least 3 are arranged horizontally with the transmitting coil located at the central axis position as the starting point, and the remaining transmitting coils are symmetrically arranged on the left and right sides, and are arranged in an alternating vertical and horizontal manner, so that after each coil is connected to the transmitter and powered on, the magnetic north direction changes regularly. The magnetic north directions of multiple transmitting coils on any one side of the central axis position are all cycled clockwise or counterclockwise, ensuring that the cycling directions on both sides are opposite, and the magnetic north direction of the coil at the central axis position is to the left or to the right. According to this specific arrangement of the transmitting coils, not only the magnetic flux of the primary field generated by the transmitting coils passing through the receiving unit is close to 0, achieving the elimination of the influence of the primary field, but also during the process of turning off the induced magnetic field generated by the current of the transmitting coils, the magnetic flux of the turned-off induced magnetic field collected by the receiving unit can be eliminated, ensuring that the receiving unit collects the secondary field signal of the underground medium, thereby improving the signal-to-noise ratio of the transient electromagnetic detection signal. In addition, due to the specific arrangement of the transmitting coils changing the magnetic field distribution, weakening the magnetic field above and enhancing the magnetic field intensity below, the intensity of the primary field generated by the transmitting coils of the present invention is also greatly improved.

[0019] According to some embodiments of the present invention, the number of the transmitting coil groups is multiple groups, and the multiple groups of the transmitting coil groups are distributed in a symmetrical structure, and the multiple groups of the transmitting coil groups are all connected to the transmitter.

[0020] According to some embodiments of the present invention, the receiving unit adopts a receiving coil or a magnetoelectric sensor.

[0021] The additional aspects and advantages of the present invention will be partly given in the following description, partly will become obvious from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0022] The above or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0023] Figure 1 is a schematic diagram of the parallel connection of the transmitting coil groups in the embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of the series connection of the transmitting coil groups in the embodiment of the present invention;

[0025] Figure 3 It is a schematic diagram of the transmitting coil according to an embodiment of the present invention;

[0026] Figure 4 It is a schematic diagram of the combination mode of a transmitting coil group provided by an embodiment of the present invention;

[0027] Figure 5 It is a schematic diagram of another combination mode of a transmitting coil group provided by an embodiment of the present invention;

[0028] Figure 6 It is a schematic diagram of the position of the receiving unit and the transmitting coil group according to an embodiment of the present invention.

[0029] Reference numerals:

[0030] Transmitting coil 100,

[0031] Transmitter 200,

[0032] Receiving unit 300,

[0033] Receiver 400. Detailed implementation manners

[0034] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention.

[0035] In the description of the present invention, it should be understood that the directions involved, such as up, down, front, back, left, right, etc., are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be construed as a limitation to the present invention.

[0036] In the description of the present invention, the meaning of several is one or more, the meaning of multiple is more than two, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If the first and second are described only for the purpose of distinguishing technical features, they should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0037] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0038] The following refers to Figures 1 to 3 a transmitting coil group according to an embodiment of the first aspect of the present invention.

[0039] The transmitting coil group according to an embodiment of the present invention includes: N transmitting coils 100, where N is an odd number and N is greater than or equal to 3. The transmitting coil 100 located at the central axis position of the N transmitting coils 100 is horizontally arranged, and the N - 1 transmitting coils 100 at non - central axis positions are symmetrically arranged on both sides of the central axis position, and the transmitting coils 100 on either side are arranged alternately in the vertical and horizontal directions; the N transmitting coils 100 are used to generate a magnetic field after being connected to a transmitter 200 and powered on; taking the magnetic field direction of the transmitting coil 100 at the central axis position as the starting direction, the magnetic north directions of the multiple transmitting coils 100 on either side of the central axis position all cycle in a clockwise or counter - clockwise direction, and the cycle directions on both sides are opposite.

[0040] Refer to Figure 1 , where the arrangement characteristics of the transmitting coil group of the present invention are introduced by taking 5 transmitting coils 100 as an example. For the convenience of understanding this embodiment, Figure 1 the 5 transmitting coils 100 shown in are numbered from left to right as left one, left two, central axis, right two, and right one in sequence, as Figure 1 shown, the transmitting coil 100 located at the central axis is horizontally arranged. Taking the dotted line shown at the transmitting coil 100 located at the central axis as the central axis, left one corresponds to right one and is also horizontally arranged, left two corresponds to right two and is vertically arranged, that is, the transmitting coils 100 on either side are arranged alternately in the vertical and horizontal directions. The 5 transmitting coils 100 are respectively connected to the transmitter 200. After being powered on, it can be seen from the direction of the arrow in Figure 1 where the arrow represents the direction of the current flow. The current flow directions of the left one transmitting coil 100 and the right one transmitting coil 100 are the same, both flowing into the right - hand end of the transmitting coil 100 and flowing out from the left - hand end. It can be known that the internal magnetic induction line directions generated by the left one transmitting coil 100 and the right one transmitting coil 100 are the same, while the current flow direction of the transmitting coil 100 located at the central axis is flowing into the left - hand end and flowing out from the right - hand end, and the internal magnetic induction line it generates is opposite to the internal magnetic induction line directions of the left one and right one transmitting coils 100. The internal magnetic induction lines of the aforementioned three transmitting coils 100 are orthogonal to the central axis of the transmitting coil group, and the internal magnetic induction lines of the remaining left two and right two transmitting coils 100 are parallel to the central axis. The current flow direction of the left two transmitting coil 100 is flowing into the upper end and flowing out from the lower end, and the current flow direction of the right two transmitting coil 100 is flowing into the lower end and flowing out from the upper end, and the internal magnetic induction line directions generated by the two transmitting coils 100 are opposite. And because the transmitting coil group is connected to the transmitter 200 according to a specific arrangement combination, a strong primary magnetic field is presented in the area below the transmitting coil group, serving as the signal transmitting end of transient electromagnetic, and at the same time, a relatively weak primary magnetic field is presented above the transmitting coil group.

[0041] It should be noted that the direction of the current in each transmitting coil 100 is not limited, and it is only necessary to ensure that the primary field measured by the receiving unit during measurement is close to 0. For example, when the magnetic north pole of the central-axis transmitting coil 100 points to the left, following the rule that the magnetic north poles of the coils on its right are arranged in a clockwise direction and the magnetic north poles of the coils on its left are arranged in a counterclockwise direction, the magnetic north poles of the five transmitting coils 100 from left to right are: right, down, left, up, right. Similarly, when the magnetic north pole of the central-axis transmitting coil 100 points to the right, the magnetic north poles of the five transmitting coils 100 from left to right are: left, up, right, down, left. For the subsequently added transmitting coils 100, the direction of their magnetic north poles should also follow the above magnetic north pole circulation rule.

[0042] It should also be noted that when increasing the number of transmitting coils 100 in the transmitting coil group, the principle of symmetry should be followed, that is, on the basis of satisfying the vertical and horizontal alternating arrangement, it is necessary to take the central axis as the axis of symmetry, and the same number of transmitting coils 100 should be added to both the left and right sides to meet the characteristics of the magnetic north pole direction circular arrangement.

[0043] According to the transmitting coil group of the embodiment of the present invention, any odd number of transmitting coils 100 with a minimum of 3 are arranged symmetrically to the left and right with the transmitting coil 100 horizontally arranged at the central axis position as the starting point, and are arranged in a vertical and horizontal alternating manner. After each coil is connected to the transmitter 200 and powered on, the direction of the magnetic north pole changes regularly. The magnetic north poles of the multiple transmitting coils 100 on either side of the central axis position all circulate in a clockwise or counterclockwise direction, ensuring that the circulation directions on both sides are opposite. The magnetic north pole of the coil at the central axis position points to the left or right. According to this specific arrangement of the transmitting coils 100, not only does the magnetic flux of the primary field generated by the transmitting coils 100 through the receiving unit 300 approach 0, achieving the elimination of the influence of the primary field, but also during the process of turning off the induced magnetic field generated by the current in the transmitting coils 100, the magnetic flux of the turned-off induced magnetic field collected by the receiving unit 300 can be eliminated, ensuring that the receiving unit 300 collects the secondary field signal of the underground medium, thereby improving the signal-to-noise ratio of the transient electromagnetic detection signal. In addition, due to the specific arrangement of the transmitting coils 100 changing the magnetic field distribution, weakening the magnetic field above and enhancing the magnetic field strength below, the intensity of the primary field generated by the transmitting coils 100 of the present invention is also greatly improved.

[0044] In some embodiments of the present invention, the winding radius of each turn of each transmitting coil 100 is equal, or increases or decreases in sequence. The size of the winding radius of the transmitting coil 100 will affect the elimination of the primary field interference. Among them, usually the choice of equal winding radius is adopted, but this embodiment does not limit this, and it is possible that the winding radius increases or decreases in sequence.

[0045] In some embodiments of the present invention, the shape of the transmitting coil 100 can be circular, triangular, regular polygon, etc. For example, Figure 2 As shown, the shape of the transmitting coil 100 in this embodiment is circular. The circular transmitting coil 100 is more convenient for installation and use during detection. However, this embodiment does not limit this. The transmitting coil 100 with the above-mentioned shape or other shapes can achieve the same effect.

[0046] In some embodiments of the present invention, referring to Figure 2 , the length l of each transmitting coil 100 is the same. The same length l of each transmitting coil 100 can reduce errors and avoid affecting the detection results due to different lengths l of the transmitting coils 100. However, this embodiment does not limit this. When the same effect can be achieved, the length l of each transmitting coil 100 is not limited, and it can be the same or different.

[0047] In some embodiments of the present invention, the diameters and the number of turns of every two transmitting coils 100 that are symmetric about the central axis are the same. In order to minimize the influence of the primary field on the receiving unit, in addition to the same setting method, the two transmitting coils 100 in the symmetric positions should maintain the same parameters in terms of the diameter d, the number of turns, and the coil winding, so as to ensure the accuracy of the detection by the receiving unit.

[0048] In some embodiments of the present invention, the transmitting coil 100 is made of paramagnetic medium material or high-permeability magnetic medium material. When the magnetic medium enters the magnetic field, it will also generate a small magnetic field under the induction of the magnetic field. The paramagnetic medium can play a role in strengthening the original magnetic field, and the high-permeability magnetic medium has the same effect, which will not be elaborated here. In addition, this embodiment does not limit this, as long as the magnetic field can be enhanced.

[0049] In some embodiments of the present invention, N transmitting coils 100 are connected in parallel with the transmitter 200. The embodiment of the transmitting coil 100 with a parallel structure has been described above and will not be elaborated here.

[0050] In some embodiments of the present invention, N of the said transmitting coils are connected in series, and the series structure formed by N of the said transmitting coils is connected to the transmitter. Referring to Figure 2 , here, the structure of the connection between the series-connected transmitting coils 100 and the transmitter 200 is also introduced by taking 5 transmitting coils 100 as an example. Similarly, the 5 transmitting coils 100 shown in Figure 2 are numbered from left to right as left one, left two, central axis, right two, and right one in sequence, as shown in Figure 2As shown, the transmitting coil 100 located on the central axis is horizontally arranged. Taking the dotted line shown at the transmitting coil 100 located on the central axis as the central axis, the leftmost one corresponds to the rightmost one and is also horizontally arranged. The second left one corresponds to the second right one and is vertically arranged, that is, the transmitting coils 100 on either side are arranged alternately in the vertical and horizontal directions. After the 5 transmitting coils 100 are connected in series with the transmitter 200 and energized, it can be seen from Figure 2 the direction of the arrow in Figure 2 . The arrow indicates the direction of the current flow. The current flow directions of the leftmost transmitting coil 100 and the rightmost transmitting coil 100 are the same, both flowing into the right end of the transmitting coil 100 and flowing out from the left end. It can be known that the directions of the internal magnetic induction lines generated by the leftmost transmitting coil 100 and the rightmost transmitting coil 100 are the same. The current flow direction of the transmitting coil 100 located on the central axis is flowing into the left end and flowing out from the right end, and the internal magnetic induction line it generates is opposite to the internal magnetic induction line directions of the leftmost and rightmost transmitting coils 100. The internal magnetic induction lines of the aforementioned three transmitting coils 100 are orthogonal to the central axis of the transmitting coil group, and the internal magnetic induction lines of the remaining second left and second right transmitting coils 100 are parallel to the central axis. The current flow direction of the second left transmitting coil 100 is flowing in from the upper end and flowing out from the lower end, and the current flow direction of the second right transmitting coil 100 is flowing in from the lower end and flowing out from the upper end. The directions of the internal magnetic induction lines generated by the two transmitting coils 100 are opposite. From the above, when the 5 transmitting coils 100 are connected in series with the transmitter 200, it also makes the area below the transmitting coil group present a strong primary magnetic field, serving as the signal transmitting end of transient electromagnetic, and at the same time, a relatively weak primary magnetic field appears above the transmitting coil group.

[0051] According to the transient electromagnetic exploration device of the second aspect of the present invention, it includes: a transmitting coil group, a transmitter 200, a receiving unit 300, and a receiver 400.

[0052] The transmitting coil group as described in any one of the first aspect;

[0053] A transmitter 200 for generating a magnetic field by N transmitting coils 100;

[0054] A receiving unit 300. The receiving plane of the receiving unit 300 is orthogonal to the central axis of the transmitting coil group and is located on the side where the magnetic force of the transmitting coil group is weak. The receiving unit 300 is used to collect the magnetic flux in the vertical direction;

[0055] A receiver 400 electrically connected to the receiving unit 300.

[0056] Reference Figures 1 to 5 , the transmitting coil group has been described in the first aspect of the embodiment and will not be elaborated here. As Figure 4As shown, the receiving unit 300 is parallel to the transmitting coil group and orthogonal to the central axis of the transmitting coil group. The receiving unit 300 is arranged above the transmitting coil group, and the upper side is the side with weak magnetic force. The receiving unit 300 collects the magnetic flux in the vertical direction. The receiver 400 is electrically connected to the receiving unit 300 to obtain the detection result.

[0057] According to the transient electromagnetic exploration device of the embodiment of the present invention, the transmitting coil group described in the first aspect is applied. Any odd number of transmitting coils 100 with a minimum of 3 are horizontally arranged with the transmitting coil 100 located at the central axis position as the starting point, and the remaining transmitting coils 100 are symmetrically arranged on both the left and right sides, and are arranged in an alternating vertical and horizontal manner. After each coil is connected to the transmitter 200 and powered on, the magnetic north direction changes regularly. The magnetic north directions of multiple transmitting coils 100 on any one side of the central axis position all circulate clockwise or counterclockwise, ensuring that the circulation directions on both sides are opposite. The magnetic north direction of the coil at the central axis position is to the left or to the right. According to this specific arrangement of the transmitting coils 100, not only can the magnetic flux of the primary field generated by the transmitting coils 100 passing through the receiving unit 300 be close to 0, achieving the elimination of the influence of the primary field, but also during the process of turning off the induced magnetic field generated by the current of the transmitting coils 100, the magnetic flux of the turned-off induced magnetic field collected by the receiving unit 300 can be eliminated, ensuring that the receiving unit 300 collects the secondary field signal of the underground medium, thereby improving the signal-to-noise ratio of the transient electromagnetic detection signal. In addition, due to the specific arrangement of the transmitting coils 100 changing the magnetic field distribution, weakening the magnetic field above and enhancing the magnetic field intensity below, the intensity of the primary field generated by the transmitting coils 100 of the present invention is also greatly improved.

[0058] In some embodiments of the present invention, the number of the transmitting coil groups is multiple groups. Refer to Figure 3 and Figure 4 , multiple groups of transmitting coil groups are distributed in a symmetric structure, and multiple groups of the transmitting coil groups are all connected to the transmitter 200. For detections in different situations, multiple groups of transmitting coil groups can be set according to the actual situation to conduct detections to obtain more accurate detection results.

[0059] In some embodiments of the present invention, the receiving unit 300 adopts a receiving coil or a magnetoelectric sensor. The magnetoelectric sensor is a sensor that utilizes the magnetoelectric coupling effect to convert the magnetic field signal into an electric field signal. It can convert a weak magnetic signal into an electric signal that is easy to measure. Since it has a relatively large output power, the matching circuit is relatively simple, and the zero position and performance are stable. However, this embodiment does not limit the receiving unit 300, and it can be reasonably selected according to the specific situation.

[0060] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0061] Although the embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, the present invention is not limited to the above embodiments. Those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present invention. The scope of the present invention is defined by the claims and their equivalents.

Claims

1. A transient electromagnetic exploration device, characterized in that, Comprising: A transmitting coil group, including N transmitting coils (100), where N is an odd number and N is greater than or equal to 3. The transmitting coil (100) located at the central axis position of the N transmitting coils (100) is horizontally arranged, and the N - 1 transmitting coils (100) at non - central axis positions are symmetrically arranged on both sides of the central axis position, and the transmitting coils (100) on any one side are arranged alternately in the vertical and horizontal directions; the N transmitting coils (100) are used to generate a magnetic field after being connected to a transmitter (200); taking the magnetic field direction of the transmitting coil (100) at the central axis position as the starting direction, the magnetic north pole directions of the multiple transmitting coils (100) on any one side of the central axis position are all in a clockwise or counter - clockwise cycle, and the cycle directions on both sides are opposite; wherein, the winding radius of each turn of each transmitting coil (100) is equal, or increases or decreases in sequence; A transmitter (200), used to make the N transmitting coils (100) generate a magnetic field; A receiving unit (300), the receiving plane of the receiving unit (300) is orthogonal to the central axis of the transmitting coil group and is located on the side with weak magnetic force of the transmitting coil group, and the receiving unit (300) is used to collect the magnetic flux in the vertical direction; A receiver (400), electrically connected to the receiving unit (300).

2. The transient electromagnetic exploration device according to claim 1, characterized in that The length of each transmitting coil (100) is the same.

3. The transient electromagnetic exploration device according to claim 1, wherein The diameters and number of turns of every two transmitting coils (100) symmetrical about the central axis position are the same.

4. The transient electromagnetic exploration device according to any one of claims 1 to 3, characterized in that, The transmitting coil (100) is made of paramagnetic medium material or high - permeability magnetic medium material.

5. The transient electromagnetic exploration device according to claim 1, characterized in that, The N transmitting coils (100) are connected in parallel with the transmitter (200).

6. The transient electromagnetic exploration device according to claim 5, characterized in that, The N transmitting coils (100) are connected in series, and the series structure formed by the N transmitting coils (100) is connected to the transmitter (200).

7. The transient electromagnetic exploration device according to claim 1, characterized in that The number of the transmitting coil groups is multiple groups, and the multiple transmitting coil groups are distributed in a symmetrical structure, and all the multiple transmitting coil groups are connected to the transmitter (200).

8. The transient electromagnetic exploration device according to claim 1, characterized in that, The receiving unit (300) uses a receiving coil or a magnetoelectric sensor.

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