Flat capacitive electrical sensor and exploration system

Abstract

The present invention relates to the technical field of geophysical exploration, and discloses a flat capacitive electrical sensor and an exploration system. The flat capacitive electrical sensor includes a receiving plate, a thin film layer, a coupling plate, an inner shielding layer, a first external wire, and a second external wire. The receiving plate, the thin film layer, and the coupling plate are sequentially stacked and connected, and the receiving plate, the thin film layer, and the coupling plate are all accommodated in the inner shielding layer. The first external wire is connected to the coupling plate, and the second external wire is connected to the inner shielding layer. The inner shielding layer is used for wrapping to shield the interference of high-frequency electromagnetic waves. An outer shielding layer can also be sleeved outside the inner shielding layer to further effectively shield the interference of the geomagnetic part of non-natural electromagnetic waves. It has strong anti-interference ability and is convenient for field operation.

Description

Technical Field

[0001] The present invention relates to the technical field of geophysical exploration, and particularly to a flat capacitive electrical sensor and an exploration system. Background Art

[0002] Geophysical exploration methods mainly include seismic method, direct current method, magnetic method, gravity method, electromagnetic method and other exploration methods. In the electrical method and electromagnetic method, the main electrodes used are metal electrodes and non-polarizable electrodes; in recent years, with the development of advanced sensing technologies, optoelectronic sensors have gradually been applied in various fields.

[0003] Metal electrodes are generally made of hard metals (such as copper, lead, etc.). The advantages are durability, low cost and easy maintenance. However, due to the large and unstable electrode polarization potential difference, it is very easy to change with the dielectric environment, and it cannot be used in some electrical method explorations (such as induced polarization method, natural electric field and magnetotelluric method, etc.).

[0004] Currently, non-polarizable electrodes include various electrodes such as copper sulfate, lead chloride, cadmium chloride, mercury chloride and silver chloride. Its characteristic is that the electrode polarization potential is not easily affected by the surrounding environment and can measure low-frequency and ultra-low-frequency signals. Therefore, it is widely used in magnetotelluric method. However, its dielectric solution needs to be soaked before use, needs to be dug deep into the ground when in use, and needs to pour brine to promote grounding when necessary, and it is relatively easy to be damaged, and both the construction difficulty and construction cost are relatively high.

[0005] The emerging optoelectronic sensors are widely used in various fields due to their advantages such as portability, less interference to the electric field, and fast dynamic response speed. However, the optoelectronic sensors have poor temperature stability, and when measuring direct current electric field and ultra-low frequency electric field, the sensing crystal will be charged under the action of the electric field to generate an additional electric field, resulting in the fact that the induced electric field inside the crystal is actually the superposition of the measured electric field and the additional electric field, and finally the measurement result of the sensor will have a large error. Summary of the Invention

[0006] Aiming at the above deficiencies, the main purpose of the present invention is to provide a flat capacitive electrical sensor and an exploration system, aiming to solve the technical problems that the existing electrodes or sensors are easily affected by external interference and are not convenient for field operations when detecting natural electromagnetic waves.

[0007] To achieve the above purpose, the present invention provides a flat capacitive electrical sensor. The flat capacitive electrical sensor includes a receiving plate, a thin film layer, a coupling plate, an inner shielding layer, a first external wire and a second external wire. The receiving plate, the thin film layer and the coupling plate are sequentially stacked and connected, and the receiving plate, the thin film layer and the coupling plate are all accommodated in the inner shielding layer. The first external wire is connected to the coupling plate, and the second external wire is connected to the inner shielding layer.

[0008] Optionally, in one embodiment, the receiving plate and the coupling plate form a first capacitor, the receiving plate and the inner shielding layer form a second capacitor, and the first capacitor is greater than the second capacitor.

[0009] Optionally, in one embodiment, the first external wire is connected to one side edge of the inner shielding layer, the second external wire is connected to one side edge of the coupling plate, and the first external wire and the second external wire are both located on the same side.

[0010] Optionally, in one embodiment, the total thickness of the receiving plate, the thin film layer and the coupling plate is 2 mm - 4 mm, the thickness of the thin film layer is 3 μm - 20 μm, and the distance between the receiving plate and the inner shielding layer is 1 mm - 10 mm.

[0011] Optionally, in one embodiment, the total thickness of the receiving plate, the thin film layer and the coupling plate is 2 mm, and the thickness of the thin film layer is 4 μm.

[0012] Optionally, in one embodiment, the thin film layer is a polyester film, and the materials of the receiving plate, the coupling plate and the inner shielding layer are copper foils.

[0013] Optionally, in one embodiment, the planar capacitive electric sensor further includes an outer shielding layer, the outer shielding layer is sleeved on the inner shielding layer, and the outer shielding layer is detachably connected to the inner shielding layer.

[0014] Optionally, in one embodiment, an avoidance position is provided on the bottom surface of the outer shielding layer, and the position of the avoidance position is close to one side of the coupling plate.

[0015] Optionally, in one embodiment, the outer shielding layer includes a sleeve body and a lid, the sleeve body and the lid are detachably connected, and the lid covers the opening of the sleeve body.

[0016] Optionally, in one embodiment, fixing blocks extend outward from both side edges of the opening of the sleeve body, connecting blocks extend outward from both side edges of the lid, and the fixing blocks are adapted to the connecting blocks.

[0017] Optionally, in one embodiment, the material of the outer shielding layer is permalloy.

[0018] The present invention also provides a prospecting system, and the prospecting system includes any one of the above-mentioned planar capacitive electric sensors.

[0019] In the technical solution provided by the present invention, the inner shielding layer is used to wrap the first capacitor to shield the interference of high-frequency electromagnetic waves, and an outer shielding layer can also be sleeved outside the inner shielding layer to further effectively shield the interference of the geomagnetic part of non-natural electromagnetic waves. It has strong anti-interference ability and is convenient for field operation. Brief Description of the Drawings

[0020] One or more embodiments are exemplarily illustrated by corresponding drawings. These exemplary illustrations do not limit the embodiments. Elements with the same reference numerals in the drawings represent similar elements, unless otherwise stated. The drawings in the figures do not constitute a scale limitation.

[0021] Figure 1 A cross-sectional view of an embodiment of the flat capacitive electric sensor provided by the present invention;

[0022] Figure 2 A schematic structural diagram of an embodiment of the outer shielding layer provided by the present invention.

[0023] In the figures: 100 - flat capacitive electric sensor; 1 - receiving plate; 2 - thin film layer; 3 - coupling plate; 4 - inner shielding layer; 5 - first external connection wire; 6 - second external connection wire, 7 - outer shielding layer; 71 - avoidance position; 72 - sleeve body; 73 - lid; 74 - fixing block; 75 - connecting block. Detailed Description of the Embodiments

[0024] For the convenience of understanding the present invention, the present invention will be described in more detail below with reference to the drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more intermediate elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more intermediate elements therebetween. The terms "vertical", "horizontal", "left", "right", "inner", "outer" and similar expressions used in this specification are only for the purpose of illustration. In the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating relative importance or implicitly indicating the quantity of the indicated technical features. Thus, unless otherwise stated, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features; the meaning of "a plurality" is two or more. The term "comprising" and any variation thereof means non-exclusive inclusion, and there may be one or more other features, integers, steps, operations, units, components and / or combinations thereof.

[0025] In addition, unless otherwise clearly defined and limited, the terms "install", "connect", and "couple" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or the internal communication of two components. All technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0026] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] Please refer to Figure 1 , the present invention provides a planar capacitive electrical sensor 100. The planar capacitive electrical sensor 100 includes a receiving plate 1, a thin film layer 2, a coupling plate 3, an inner shielding layer 4, a first external wire 5, and a second external wire 6. The receiving plate 1, the thin film layer 2, and the coupling plate 3 are sequentially stacked and connected. The inner shielding layer 4 has a hollow rectangular cavity structure. The receiving plate 1, the thin film layer 2, and the coupling plate 3 are all accommodated in the inner shielding layer. The inner shielding layer 4 is in a fully enclosed form, and the shape of the hollow rectangular cavity of the inner shielding layer 4 is adapted to the shape after the receiving plate 1, the thin film layer 2, and the coupling plate 3 are stacked and connected. The first external wire 5 is connected to the coupling plate 3, and the second external wire 6 is connected to the inner shielding layer 4. The receiving plate 1 and the coupling plate 3 form a first capacitor, denoted as C1. The receiving plate 1 and the inner shielding layer 4 form a second capacitor, denoted as C2. The first capacitor C1 is greater than the second capacitor C2. Since the distance between the receiving plate 1 and the coupling plate 3 is relatively close, the capacitance is relatively large. The distance between the receiving plate 1 and the inner shielding layer 4 is relatively large, so its capacitance is relatively small and can be approximated as zero. A potential difference is formed between the first capacitor C1 and the second capacitor C2, and this potential difference is the signal received by the planar capacitive electrical sensor 100.

[0028] In this embodiment, the first external wire 5 is connected to one side edge of the coupling plate 3, and the second external wire 6 is connected to one side edge of the inner shielding layer 4. Moreover, both the first external wire 5 and the second external wire 6 are located on the same side. After being led out, the first external wire 5 and the second external wire 6 can be connected to the input end of an external instrument through an aviation socket. If the external wire is led out through a perforation in the middle of the inner shielding layer 4 and / or the coupling plate 3, it will inevitably affect the effects of the first capacitor C1 and the second capacitor C2. If the center point welding method is adopted, it will also affect the second capacitor C2. Therefore, the edge connection method, that is, the method of leading out from the side edge, can avoid affecting the first capacitor C1 and the second capacitor C2. Additionally, in practical applications, in order to avoid magnetic field interference between the first external wire 5 and the second external wire 6, the wire distance between the first external wire 5 and the second external wire 6 should be relatively far apart.

[0029] In a certain embodiment, the total thickness of the receiving plate 1, the thin film layer 2, and the coupling plate 3 is in the range of 2 mm to 4 mm, and the thickness of the thin film layer 2 is controlled in the range of 3 μm to 4 μm. The distance between the receiving plate 1 and the inner shielding layer 4 is 1 mm to 10 mm. If the receiving plate 1, the thin film layer 2, and the coupling plate 3 are directly contact-clamped, it will cause air gaps in the thin film layer 2, affecting the magnitude of the dielectric constant. Therefore, the thin film layer 2 can be made by the method of uniform coating, and the distance between the receiving plate 1 and the coupling plate 3 is strictly controlled.

[0030] In this embodiment, it is preferred that the total thickness of the receiving plate 1, the thin film layer 2, and the coupling plate 3 is 2 mm, and the thickness of the thin film layer 2 is 4 μm. According to the capacitance formula and the characteristics of series capacitor voltage division, it is estimated that the voltage division of the two capacitors differs by approximately 500 to 1000 times. The voltage division of the first capacitor C1 is almost zero, and the received signal magnitude is approximately equal to the voltage of the second capacitor C2.

[0031] In this embodiment, the thin film layer 2 is a polyester film, and the materials of the receiving plate 1, the coupling plate 3, and the inner shielding layer 5 are copper foils. The polyester film has characteristics such as high tensile strength, high dielectric constant, low loss factor, good thickness uniformity, high resistivity, and good electrical properties, and can be used in capacitor dielectrics and insulating barriers. The copper foil is a metal foil conductive material with an electromagnetic shielding effect and can shield electromagnetic signals. The aluminum foil is also a metal foil conductive material. In some scenarios, the copper foil can also be replaced by the aluminum foil.

[0032] Please refer to Figure 1-2, in this embodiment, in order to further shield the interference of the magnetic field of the electro - geological part of non - natural electromagnetic waves, the flat - plate capacitive electrical sensor 100 further includes an outer shielding layer 7. The outer shielding layer 7 is sleeved on the inner shielding layer 4 in a semi - wrapping manner. An avoidance position 71 is provided on the bottom surface of the outer shielding layer 7, which is wrapped around the inner shielding layer 4 in a structure similar to a concave - shaped structure, and the position of the avoidance position 71 is close to one side of the coupling plate 3, which is beneficial to the coupling surface of the coupling plate 3 to be coupled with the detected target. The outer shielding layer 7 is detachably connected to the inner shielding layer 4.

[0033] In this embodiment, the outer shielding layer 7 includes a sleeve body 72 and a lid 73, and the lid 73 covers the opening of the sleeve body 73. Fixing blocks 74 extend outward from both sides of the opening of the sleeve body 72, connecting blocks 75 extend outward from both sides of the lid 73, and the fixing blocks 74 and the connecting blocks 75 are adapted to each other. The sleeve body 72 and the lid 73 are detachably connected through the fixing blocks 74 and the connecting blocks 75. The outer shielding layer 7 is connected in a combined manner of the sleeve body 72 and the lid 73, and joint positions extend out on both sides of the connection part, and no holes are punched on the upper surface of the outer shielding layer 7. In order to reduce the influence of the seams, all seams are covered, and the dimensions are required to fit as closely as possible.

[0034] In this embodiment, the material of the outer shielding layer 7 is permalloy, that is, iron - nickel alloy, which can effectively shield the interference of the magnetic field of the electro - geological part of non - natural electromagnetic waves.

[0035] The present invention also provides a prospecting system (not shown in the figure), and the prospecting system includes any one of the above - mentioned flat - plate capacitive electrical sensors.

[0036] The advantages of the present invention are as follows: a first capacitor is formed by using a receiving plate, a thin - film layer, and a coupling plate, and a second capacitor is formed by the receiving plate and the inner shielding layer. The potential difference formed between the first capacitor and the second capacitor is the signal received by the flat - plate capacitive electrical sensor, which has the advantages of strong anti - interference ability and convenient field operation; compared with traditional metal electrodes and photoelectric sensors, it is not easily affected by the surrounding environment and can measure low - frequency and ultra - low - frequency signals; compared with traditional non - polarized electrodes, there is no need to dig pits for deep burial, pour salt water to promote grounding, or use long wires during the measurement process, and the construction is simple and the operation is convenient.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A flat capacitive electrical sensor, characterized in that, The flat capacitive electrical sensor includes a receiving plate, a thin film layer, a coupling plate, an inner shielding layer, a first external wiring and a second external wiring. The receiving plate, the thin film layer and the coupling plate are sequentially stacked and connected, and the receiving plate, the thin film layer and the coupling plate are all accommodated in the inner shielding layer. The first external wiring is connected to the coupling plate, and the second external wiring is connected to the inner shielding layer. The receiving plate and the coupling plate form a first capacitor, and the receiving plate and the inner shielding layer form a second capacitor, and the first capacitor is greater than the second capacitor. The first external wiring is connected to one side of the inner shielding layer, and the second external wiring is connected to one side of the coupling plate, and the first external wiring and the second external wiring are both located on the same side. A potential difference is formed between the first capacitor and the second capacitor, and the potential difference is a signal received by the flat capacitive electrical sensor.

2. The flat capacitive electrical sensor according to claim 1, characterized in that, The total thickness of the receiving plate, the film layer and the coupling plate is 2 mm-4 mm, the thickness of the film layer is 3 μm-20 μm, and the spacing between the receiving plate and the inner shielding layer is 1 mm-10 mm.

3. The planar capacitive electrical sensor according to claim 2, characterized in that, The total thickness of the receiving plate, the film layer and the coupling plate is 2 mm, and the thickness of the film layer is 4 μm.

4. The flat capacitive electrical sensor according to claim 1, wherein The film layer is a polyester film, and the receiving plate, the coupling plate and the inner shielding layer are made of copper foil.

5. The planar capacitive electrical sensor according to any one of claims 1-4, characterized in that, The flat capacitive electric sensor further comprises an outer shielding layer, which is sleeved on the inner shielding layer, and the outer shielding layer is detachably connected to the inner shielding layer.

6. The flat capacitive electrical sensor according to claim 5, characterized in that, The bottom surface of the outer shielding layer is provided with an avoidance position, and the avoidance position is located close to one side of the coupling plate.

7. The flat capacitive electrical sensor according to claim 6, characterized in that, The outer shielding layer comprises a sleeve body and a cover, wherein the sleeve body and the cover are detachably connected, and the cover covers the opening of the sleeve body.

8. The flat capacitive electric sensor according to claim 7, wherein Both sides of the opening of the sleeve body extend outwardly to form fixing blocks, and both sides of the cover extend outwardly to form connecting blocks, and the fixing blocks are matched with the connecting blocks.

9. The flat capacitive electrical sensor according to claim 5, characterized in that, The material of the outer shielding layer is Permalloy.

10. An exploration system, characterized in that, The exploration system comprises the flat-plate capacitive electric sensor according to any one of claims 1-9.

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