Electromagnetic metamaterial wave absorber based on continuous dielectric layer

Abstract

The invention discloses an electromagnetic metamaterial wave absorber based on a continuous dielectric layer, and relates to the technical field of electromagnetic wave propagation and reception, and the wave absorber comprises a continuous metal layer, a continuous dielectric layer and a resonant ring array which are sequentially arranged from bottom to top and are tightly attached. The continuous metal layer is made of a metal copper material; the resonant ring array comprises at least one resonant ring, and each resonant ring is provided with a correspondingly arranged metal opening; the continuous dielectric layer is made of a flexible polyimide material doped with nano particles in a specific proportion so as to adjust the dielectric constant of the continuous dielectric layer, and the electromagnetic metamaterial wave absorber is simple in structure and can generate an absorption peak with the absorption rate of 99.96% at the frequency of 0.192 THz. The invention further discloses a method for measuring the magnetic field intensity of the high-voltage direct-current power transmission line by adopting the wave absorber, the sensitive response to the magnetic field is realized by designing the wave absorber with a specific structure, and the high-precision measurement of the magnetic field in the high-voltage direct-current power transmission line is further realized.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic wave propagation and reception, and in particular to an electromagnetic metamaterial absorber based on a continuous dielectric layer. Background Art

[0002] When transmitting electric energy, high-voltage direct current transmission lines will also generate a certain magnetic field strength, which may affect the surrounding environment, human health and the normal operation of power equipment. Therefore, the measurement of the magnetic field strength of high-voltage direct current transmission lines is particularly important.

[0003] Electrical testing technology is a key means to confirm the energized status of high-voltage equipment and the safe working distance. The electrical tester is an indispensable tool for operation, maintenance and personnel safety in the power industry.

[0004] As a new type of artificial composite material, electromagnetic metamaterials have great potential in electromagnetic field regulation due to their unique electromagnetic properties, such as negative refractive index, abnormal transmission and reflection characteristics, etc. For example, in measuring the magnetic field strength of high-voltage direct current transmission lines, electromagnetic metamaterials can achieve sensitive response to magnetic fields by designing specific structures, thereby achieving high-precision magnetic field measurements.

[0005] However, existing electromagnetic metamaterials still have some shortcomings in magnetic field measurement, such as insufficient measurement accuracy, insufficient stability, and susceptibility to environmental interference. In addition, the preparation process and cost of electromagnetic metamaterials are also important factors restricting their widespread application. Summary of the invention

[0006] In view of this, the present invention provides an electromagnetic metamaterial absorber based on a continuous dielectric layer to overcome the technical problems of existing electromagnetic metamaterials in magnetic field measurement, such as high accuracy and poor stability.

[0007] To solve the above problems, the first object of the present invention is to provide an electromagnetic metamaterial absorber based on a continuous dielectric layer, comprising a continuous metal layer, a continuous dielectric layer and a resonant ring array arranged in sequence from bottom to top and in close contact;

[0008] The continuous metal layer is made of metal copper;

[0009] The resonant ring array comprises at least one resonant ring, and each of the resonant rings has a correspondingly arranged metal opening;

[0010] The continuous dielectric layer is made of a flexible polyimide material doped with nanoparticles in a specific proportion to adjust the dielectric constant of the continuous dielectric layer.

[0011] Furthermore, each of the resonant rings is in the shape of a rectangular parallelepiped structure, and the metal opening is opened at the center position of a long side of the rectangular parallelepiped structure.

[0012] Furthermore, the resonant ring has a length of 14.8-15.2 mm, a width of 11.8-12.2 mm, and a thickness of 0.028-0.032 mm.

[0013] Furthermore, the width of the metal opening is 4.8-5.2 mm.

[0014] Furthermore, the nanoparticles include any one of barium titanate, magnetic metal, magnetic oxide and semiconductor.

[0015] Furthermore, the thickness of the continuous metal layer is designed to be gradual, and the thickness of the continuous metal layer ranges from 1.8 to 2.2 mm.

[0016] Furthermore, the number of the resonant rings is four.

[0017] Furthermore, the resonant ring is made of metallic copper material.

[0018] Furthermore, the resonant rings are evenly distributed.

[0019] The second object of the present invention is to provide a method for measuring the magnetic field strength of a high voltage direct current transmission line, using the electromagnetic metamaterial absorber based on a continuous dielectric layer as described above, the method comprising:

[0020] Step S 100 :Identify the magnitude and direction of the magnetic field of the high-voltage DC transmission line through the absorber;

[0021] Step S 200 : Choose a flat terrain and install the absorber at a height of no more than 1.5m from the ground;

[0022] Step S 300 :Measure the magnetic field of high voltage DC transmission lines;

[0023] Step S 400 : Analyze the measured absorption rate and frequency.

[0024] Compared with the prior art, the present invention has significant advantages and beneficial effects, which are specifically embodied in the following aspects:

[0025] The electromagnetic metamaterial absorber based on the continuous dielectric layer in the present invention is composed of a continuous metal layer, a continuous dielectric layer and a resonant ring array. This structural design utilizes the conductivity of the metal layer and the dielectric properties of the dielectric layer, as well as the electromagnetic resonance characteristics of the resonant ring array to achieve effective absorption of electromagnetic waves. The continuous metal layer provides a good conductive path, which can reflect and absorb incident electromagnetic waves; the resonant ring array generates resonance through its metal openings to enhance the absorption of electromagnetic waves of a specific frequency; the continuous dielectric layer is made of a flexible polyimide material doped with nanoparticles, and the dielectric constant of this composite material can be adjusted by changing the type and proportion of nanoparticles, thereby affecting the resonant frequency and bandwidth of the electromagnetic metamaterial absorber. The dielectric properties of the continuous dielectric layer can adjust the dielectric constant of the dielectric layer by doping a specific proportion of nanoparticles, thereby optimizing the wave absorption performance. Each resonant ring in the resonant ring array has a metal opening, which resonates under the action of electromagnetic waves, thereby achieving efficient absorption of electromagnetic waves at a specific frequency. Therefore, the embodiment of the present invention achieves effective absorption of electromagnetic waves through a carefully designed multilayer structure and nanoparticle doping, and has wide-angle, wide-band and highly stable wave absorption performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of the three-dimensional structure of an electromagnetic metamaterial absorber based on a continuous dielectric layer in an embodiment of the present invention;

[0027] Figure 2 is a schematic diagram of the three-dimensional structure of the resonant ring in an embodiment of the present invention;

[0028] Figure 3 is a schematic diagram of a curve of the absorber measuring the magnetic field strength in a high-voltage direct current transmission line in an embodiment of the present invention;

[0029] Figure 4 It is a schematic flow chart of a method for measuring the magnetic field strength of a high-voltage direct current transmission line in an embodiment of the present invention.

[0030] Reference numerals:

[0031] 1- continuous metal layer;

[0032] 2-continuous dielectric layer;

[0033] 3-resonance ring array; 31-resonance ring; 311-metal opening. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0035] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should 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 a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In addition, the directional words such as front, back, top, and bottom involved in this article are defined by the positions of the components in the drawings and the positions of the components relative to each other, just for the sake of clarity and convenience in expressing the technical solution. It should be understood that the use of the directional words should not limit the scope of protection requested by this application.

[0037] See also Figure 1-3 As shown, an embodiment of the present invention provides an electromagnetic metamaterial absorber based on a continuous dielectric layer, wherein the electromagnetic metamaterial absorber comprises a continuous metal layer 1, a continuous dielectric layer 2 and a resonant ring array 3 which are sequentially arranged and closely attached from bottom to top, wherein:

[0038] The continuous metal layer 1 is made of metal copper; the resonant ring array 3 includes at least one resonant ring 31, and each resonant ring 31 has a correspondingly arranged metal opening 311; the continuous dielectric layer 2 is made of a flexible polyimide material doped with nanoparticles in a specific proportion to adjust the dielectric constant of the continuous dielectric layer 2.

[0039] Specifically in this embodiment, the electromagnetic metamaterial absorber is composed of a continuous metal layer 1, a continuous dielectric layer 2 and a resonant ring array 3. This structural design utilizes the conductivity of the metal layer and the dielectric properties of the dielectric layer, as well as the electromagnetic resonance characteristics of the resonant ring array to achieve effective absorption of electromagnetic waves. The continuous metal layer 1 provides a good conductive path, which can reflect and absorb incident electromagnetic waves; the resonant ring array 3 generates resonance through its metal opening 311 to enhance the absorption of electromagnetic waves of a specific frequency; the dielectric properties of the continuous dielectric layer 2 can adjust the dielectric constant of the dielectric layer by doping a specific proportion of nanoparticles, thereby optimizing the wave absorption performance.

[0040] Preferably, the continuous dielectric layer 2 is made of a flexible polyimide material (mass fraction 1%) doped with nanoparticles (mass fraction 5%). The dielectric constant of this composite material can be adjusted by changing the type and proportion of the nanoparticles, thereby affecting the resonant frequency and bandwidth of the absorber.

[0041] Each resonant ring 31 in the resonant ring array 3 has a metal opening 311 , which generates resonance under the action of electromagnetic waves, thereby achieving efficient absorption of electromagnetic waves at a specific frequency.

[0042] Therefore, the embodiment of the present invention achieves effective absorption of electromagnetic waves through a carefully designed multilayer structure and nanoparticle doping, and has wide-angle, wide-band and highly stable wave absorbing performance.

[0043] For further information, see Figure 1 , 2 As shown, each resonant ring 31 is in the shape of a rectangular parallelepiped structure, and the metal opening 311 is opened at the center position of a long side of the rectangular parallelepiped structure.

[0044] Specifically, the resonant ring 31 of the rectangular parallelepiped structure achieves resonance through its metal opening 311. The position and size of the metal opening 311 have an important influence on the resonant frequency. The opening located at the center of the long side can optimize the resonant condition of the electromagnetic wave and enhance the absorption of electromagnetic waves of a specific frequency. When the electromagnetic wave is incident on the absorber, the resonant ring 31 of the rectangular parallelepiped can resonate with the incident wave due to its geometric characteristics and the metal opening 311, thereby achieving effective conversion and absorption of electromagnetic energy. This resonance effect enables the absorber to have a high absorption rate within a specific frequency range.

[0045] It should be noted that in order to achieve perfect wave absorption, the unit structure of the metamaterial needs to be designed so that its equivalent electromagnetic parameters (dielectric constant and magnetic permeability) are equal and meet the impedance matching relationship. Matching allows the incident wave to enter the wave absorbing structure without reflection, and the energy loss is contributed by the imaginary part of the complex equivalent electromagnetic parameter. Therefore, by designing the imaginary part, the energy can be dissipated to the maximum extent, thereby reducing transmission and achieving perfect wave absorption.

[0046] For further information, see Figure 2 As shown, the length L1 of the resonant ring 31 is 14.8-15.2 mm, the width L2 is 11.8-12.2 mm, and the thickness H5 is 0.028-0.032 mm.

[0047] It should be noted that the size of the resonant ring 31 directly affects its resonant frequency. According to electromagnetic wave theory, the resonant frequency of the resonant ring 31 is inversely proportional to its physical size. Therefore, the length, width and thickness of the resonant ring 31 jointly determine its resonant frequency. Within a given size range, the resonant ring 31 will resonate with electromagnetic waves of a specific frequency.

[0048] As a preferred embodiment of the present invention, the length L1 of the resonant ring 31 is selected as 15 mm, the width L2 is selected as 12 mm, and the thickness H5 is selected as 0.03 mm. By precisely controlling the size of the resonant ring 31, impedance matching with the surrounding medium can be achieved, thereby reducing reflection and increasing absorption.

[0049] The size of the resonant ring 31 determines the strength of its interaction with the electromagnetic wave. Near the resonant frequency, the resonant ring will show the maximum absorption efficiency, because the size of the resonant ring 31 matches its resonant frequency, causing the electromagnetic wave energy to be concentrated on the ring and absorbed.

[0050] Therefore, the size parameters of the resonant ring 31 have an important influence on its electromagnetic characteristics such as resonant frequency, absorption efficiency and impedance matching. By precisely controlling these parameters, an absorber with excellent performance can be designed to meet specific application requirements.

[0051] For further information, see Figure 1 , 2 As shown, the width of the metal opening 311 is 4.8-5.2 mm. In this embodiment, the lengths L3 and L4 on both sides of the metal opening 311 are both set to 5 mm, that is, the width of the metal opening 311 is preferably set to 5 mm.

[0052] Specifically, the width of the metal opening 311 directly affects the resonant frequency of the resonant ring 31. According to the equivalent circuit model, the resonant frequency f0 can be calculated by the following formula:

[0053]

[0054] Among them, L 总 is the total inductance, and C0 is the series capacitance between the double loops on the left and right sides of the opening gap. A change in the opening width changes the capacitance value, thus affecting the resonant frequency.

[0055] Thus, the change of the opening width can affect the broadband absorption characteristics of the absorber. By adjusting the opening width, the resonance bandwidth can be increased or decreased while maintaining the center resonance frequency to meet different application requirements.

[0056] Furthermore, the nanoparticles include any one of barium titanate, magnetic metal, magnetic oxide and semiconductor.

[0057] Specifically, barium titanate (BaTiO3) is a ferroelectric material with a perovskite structure that is widely used in capacitors and sensors. Its nanoparticle form exhibits higher dielectric constant and piezoelectric properties due to its size effect. In the field of gas sensing, barium titanate is regarded as a promising material due to its long-term stability and perovskite structure.

[0058] Magnetic metal nanoparticles such as iron, cobalt, nickel, etc., due to their unique magnetic properties, provide the necessary conditions to act as catalysts and can greatly improve reaction efficiency.

[0059] Magnetic oxides such as iron oxide (Fe3O4) and nickel oxide (NiO) not only perform well in the field of catalysis, but also play a role in environmental governance such as pollutant decomposition.

[0060] Semiconductor nanoparticles such as silicon and gallium arsenide have important applications in optoelectronic devices and energy and environmental protection due to their quantum size effect and surface effect. The electrons and holes generated by these nanoparticles under light irradiation have strong reduction and oxidation capabilities and can be used for solar catalytic decomposition of inorganic and organic substances.

[0061] For further information, see Figure 1 , 2 As shown, the thickness of the continuous metal layer 1 is designed to be gradual, and the thickness of the continuous metal layer 1 ranges from 1.8 to 2.2 mm.

[0062] Therefore, the thickness gradient design of the continuous metal layer 1 helps to achieve impedance matching, which is one of the key factors to improve the absorption efficiency. Through the gradient design, the impedance of the electromagnetic metamaterial absorber can be gradually changed, so as to better match the wave impedance of the free space, reduce the reflection of electromagnetic waves, and improve the absorption efficiency.

[0063] For further information, see Figure 1 , 2 As shown, the number of the resonant rings 31 is four.

[0064] The four resonant rings 31 can be designed to have different resonant frequencies, thereby covering a wider frequency range. This design can enable the absorber to achieve efficient absorption at multiple frequencies and increase the width of its operating frequency band.

[0065] The mutual coupling between the resonant rings 31 can further adjust the wave absorption performance. By accurately designing the size and relative position of each resonant ring 31, the resonant frequency can be fine-tuned to optimize the wave absorption effect.

[0066] For further information, see Figure 2 As shown, the resonant ring 31 is made of metal copper material.

[0067] The resonant ring 31 in this embodiment is made of metal copper material, which is specifically reflected in the following aspects:

[0068] First, copper has a very high electrical conductivity (5.8×10 7 S / m), which enables the resonant ring 31 to generate a strong surface current response under the action of electromagnetic waves. This high conductivity helps to improve the electromagnetic coupling efficiency of the resonant ring, thereby enhancing the wave absorption effect.

[0069] Secondly, under the action of external electromagnetic radiation, a current loop will form on the surface of the metal copper resonant ring, and the current will flow around the metal ring. The distribution of this surface current is crucial to the magnetic resonance characteristics of the resonant ring, which helps to achieve efficient electromagnetic wave absorption at a specific frequency.

[0070] Furthermore, the high conductivity and low loss characteristics of metal copper enable the resonant ring 31 to resonate at a specific frequency, thereby achieving selective absorption of electromagnetic waves of a specific frequency. By adjusting the size and shape of the resonant ring 31, the resonant frequency can be further adjusted to achieve absorption of electromagnetic waves of different frequencies.

[0071] Finally, the metal copper resonant ring can generate magnetic resonance and electric resonance at the same time under the action of electromagnetic waves. The magnetic resonance is mainly related to the current distribution in the metal ring, while the electric resonance is related to the accumulation of charge on the metal ring. The interaction of these two resonances can improve the overall absorption performance of the absorber.

[0072] Therefore, the high conductivity, surface current distribution characteristics, resonant frequency control capability, magnetoelectric resonance effect, thermal and mechanical stability, and tunability of the metal copper resonant ring work together to improve the performance of the absorber and achieve efficient and stable electromagnetic wave absorption.

[0073] For further information, see Figure 1 As shown, the resonant rings 31 are evenly distributed. The evenly distributed design of the resonant rings 31 helps to improve the uniform response, broadband absorption capacity, polarization and angle insensitivity of the absorber, and provides more space for structural optimization, thereby improving the overall performance of the absorber.

[0074] In some other embodiments, the resonant ring 31 also adopts a non-uniform arrangement or a variable size design, which can achieve efficient electromagnetic wave absorption in a wider frequency range.

[0075] See also Figure 4 As shown, an embodiment of the present invention further provides a method for measuring the magnetic field strength of a high-voltage direct current transmission line, using the electromagnetic metamaterial absorber based on a continuous dielectric layer as described above, the method comprising:

[0076] Step S 100 :Identifying the magnitude and direction of the magnetic field of a high-voltage DC transmission line through electromagnetic metamaterial absorbers;

[0077] Step S 200 : Choose a flat terrain and install the absorber at a height of no more than 1.5m from the ground;

[0078] Step S 300 :Measure the magnetic field of high voltage DC transmission lines;

[0079] Step S 400 : Analyze the measured absorption rate and frequency.

[0080] Specifically in this embodiment, the method for measuring the magnetic field strength of a high-voltage direct current transmission line using an electromagnetic metamaterial absorber based on a continuous dielectric layer has the following specific process:

[0081] Step 1: Magnetic Field Identification

[0082] The electromagnetic metamaterial absorber can identify the magnitude and direction of the magnetic field generated by the high-voltage direct current transmission line through its metal layer, continuous dielectric layer and resonant ring array structure. Due to its high conductivity, the metal layer will generate an induced current under the action of the electromagnetic field, thereby identifying the existence and characteristics of the magnetic field.

[0083] Step 2: Terrain selection and height setting

[0084] The absorber is installed on a flat terrain no more than 1.5m above the ground to ensure the consistency and accuracy of the measurement. The flat terrain helps to reduce the interference of the terrain on the magnetic field measurement, and the height of 1.5m is based on the fact that the magnetic field strength decreases with the increase of the height from the ground, and it is also convenient for practical operation.

[0085] Step 3: Magnetic Field Measurement Method

[0086] When measuring the magnetic field of a high-voltage DC transmission line, dedicated electromagnetic metamaterial absorbers should be used. These instruments can identify the magnitude and direction of the DC magnetic field. When using a one-dimensional probe, it is necessary to measure the three orthogonal components of the DC magnetic field and calculate the resultant to obtain comprehensive information about the magnetic field.

[0087] Step 4: Absorption and frequency analysis

[0088] The purpose of analyzing the measured wave absorption rate and frequency is to evaluate the performance of the electromagnetic metamaterial absorber and determine its operating frequency range. By analyzing the relationship between the wave absorption rate and the frequency, we can understand the wave absorption effect of the electromagnetic metamaterial absorber at different frequencies, and then optimize the design and improve the wave absorption efficiency.

[0089] Therefore, by using a continuous dielectric layer-based absorber to measure the magnetic field, we can use its sensitivity to electromagnetic waves and its wave absorption characteristics to accurately measure the magnetic field of the high-voltage DC transmission line. This method can provide detailed characteristics of the magnetic field, including size, direction and frequency distribution, which is of great significance for evaluating the impact of transmission lines on the surrounding environment and ensuring power transmission safety.

[0090] This measurement method utilizes the electromagnetic properties of electromagnetic metamaterial absorbers. Through precise measurement steps and analysis, it can efficiently measure the magnetic field strength of high-voltage direct current transmission lines, providing a scientific basis for the safe operation of power systems and environmental impact assessment.

[0091] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. An electromagnetic metamaterial absorber based on a continuous dielectric layer, characterized in that: It comprises a continuous metal layer (1), a continuous dielectric layer (2) and a resonant ring array (3) which are arranged in sequence from bottom to top and closely fit together; The continuous metal layer (1) is made of metal copper; The resonant ring array (3) comprises at least one resonant ring (31), and each of the resonant rings (31) has a correspondingly arranged metal opening (311); The continuous dielectric layer (2) is made of a flexible polyimide material doped with nanoparticles in a specific proportion, so as to adjust the dielectric constant of the continuous dielectric layer (2).

2. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: Each of the resonant rings (31) is in the shape of a rectangular parallelepiped structure, and the metal opening (311) is opened at the center position of a long side of the rectangular parallelepiped structure.

3. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 2, characterized in that: The resonant ring (31) has a length of 14.8-15.2 mm, a width of 11.8-12.2 mm, and a thickness of 0.028-0.032 mm.

4. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 2, characterized in that: The width of the metal opening (311) is 4.8-5.2 mm.

5. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: The nanoparticles include any one of barium titanate, magnetic metal, magnetic oxide and semiconductor.

6. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: The thickness of the continuous metal layer (1) is designed to be gradually changed, and the thickness of the continuous metal layer (1) is in the range of 1.8-2.2 mm.

7. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: The number of the resonant rings (31) is four.

8. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: The resonant ring (31) is made of metallic copper material.

9. The electromagnetic metamaterial absorber based on a continuous dielectric layer according to claim 1, characterized in that: The resonant rings (31) are evenly distributed.

10. A method for measuring the magnetic field strength of a high voltage direct current transmission line, using the electromagnetic metamaterial absorber based on a continuous dielectric layer according to any one of claims 1 to 9, characterized in that: The method comprises: Step S 100 :Identify the magnitude and direction of the magnetic field of the high-voltage DC transmission line through the absorber; Step S 200 : Choose a flat terrain and install the absorber at a height of no more than 1.5m from the ground; Step S 300 : Measure the magnetic field of high voltage DC transmission lines; Step S 400 : Analyze the measured absorption rate and frequency.

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