Metamaterial-based four-coil electric energy direction-changing wireless enhanced transmission device and method

Abstract

The invention relates to a four-coil electric energy turning wireless enhanced transmission device and method based on metamaterials. The antenna comprises a high-frequency power supply, a transmitting coil connected with the high-frequency power supply, a receiving coil, a metamaterial coil array arranged between the transmitting coil and the receiving coil, an external capacitor connected with the metamaterial coil array, and a load connected with the receiving coil, the metamaterial coil array comprises three groups of first metamaterial coils, three groups of second metamaterial coils and three groups of third metamaterial coils, nine groups of metamaterial coils are arranged to form a square, and the transmitting coil and the receiving coil are vertically arranged. And the metamaterial coil array is arranged on an angular bisector of the transmitting coil and the receiving coil. According to the invention, the problem of low efficiency in radio transmission is solved, and the stability and efficiency in the radio power transmission process are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless power transmission, and in particular to a four-coil electric energy directional wireless enhanced transmission device and method based on metamaterials. Background Art

[0002] In coal mines, electrical equipment is usually powered by wired cables, batteries, or a combination of the two. Since coal mine tunnels are narrow, equipment must move with the working face, which makes wired cable power supply very cumbersome, and the dense cable network increases the difficulty of maintenance. At present, my country's coal production enterprises generally use traditional wired charging methods, which causes many inconveniences in actual operations and affects the safe production of mines.

[0003] Wireless power transmission is a contactless power supply technology. The existing wireless power transmission usually has the transmitting coil and the receiving coil set in parallel, which is inconvenient for power supply installation in coal mines. Electromagnetic metamaterials have the characteristics of negative refraction and negative magnetic permeability, which can change the direction of energy transmission. However, although the use of electromagnetic metamaterials can change the direction of energy transmission, it will reduce the transmission efficiency of radio.

[0004] Therefore, it is necessary to provide a new four-coil electric energy redirection wireless enhanced transmission device and method based on metamaterials. Summary of the invention

[0005] Based on the above problems existing in the prior art, the purpose of the embodiments of the present invention is to provide a four-coil electric energy redirection wireless enhanced transmission device and method based on metamaterials, which solves the problem of low efficiency in radio transmission and improves the stability and efficiency of the wireless power transmission process.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a four-coil electric energy redirection wireless enhanced transmission device based on metamaterials, comprising: a high-frequency power supply, a transmitting coil connected to the high-frequency power supply, a receiving coil, a metamaterial coil array arranged between the transmitting coil and the receiving coil, an external capacitor connected to the metamaterial coil array, and a load connected to the receiving coil, the metamaterial coil array comprising three groups of first metamaterial coils, three groups of second metamaterial coils and three groups of third metamaterial coils, a total of nine groups of metamaterial coils are arranged to form a square, and the spacing between two adjacent metamaterial coils is equal, the nine groups of metamaterial coils are all arranged on an FR4 substrate, the transmitting coil and the receiving coil are arranged vertically, and the metamaterial coil array is arranged on the angular bisector of the transmitting coil and the receiving coil.

[0007] Furthermore, the high-frequency power supply generates a high-frequency alternating current with a frequency of 6 MHz, the transmitting coil 2 and the receiving coil have the same structure, and the transmitting coil and the receiving coil both have a cross-sectional area of ​​0.491 mm 2 The excitation wire is wound to form a circular coil with a diameter of 34 cm and 6 turns.

[0008] Furthermore, a first resonant capacitor is provided at one end of the transmitting coil, and the high-frequency power supply is connected in series with the transmitting coil and the first resonant capacitor to generate wireless power with a resonant frequency.

[0009] Furthermore, a third resonant capacitor is provided at one end of the receiving coil, and the load is connected in series with the receiving coil and the third resonant capacitor for sensing magnetic field energy and converting the magnetic field energy into electrical energy to power the load.

[0010] Furthermore, a transmitting end excitation coil is provided on one side of the transmitting coil, the transmitting end excitation coil is provided on a side of the transmitting coil close to the metamaterial coil array, the transmitting end excitation coil is parallel to the transmitting coil, and a second resonant capacitor is provided at one end of the transmitting end excitation coil, and the second resonant capacitor is connected in series with the transmitting end excitation coil.

[0011] Furthermore, a receiving end excitation coil is provided on one side of the receiving coil, and the receiving end excitation coil is provided on a side of the transmitting coil close to the metamaterial coil array, and the receiving end excitation coil is parallel to the receiving coil. A fourth resonant capacitor is provided at one end of the receiving end excitation coil, and the fourth resonant capacitor is connected in series with the receiving end excitation coil.

[0012] Furthermore, the number of the external capacitors is equal to the number of groups of metamaterial coils, each group of metamaterial coils is respectively connected to the external capacitor C0, the FR4 substrate is a square, one side of the FR4 substrate is a copper wire wound with three spiral circles of a square as a group of metamaterial coils, and the joint of the copper wire of each group of metamaterial coils has two through holes, the through holes connect the front and back sides of the FR4 substrate, and the external capacitor is welded on the other side of the FR4 substrate through the two through holes, and the nine groups of metamaterial coils are connected in series head to tail through multiple external capacitors.

[0013] A four-coil electric energy direction-changing wireless enhanced transmission method based on metamaterials is applied to the above-mentioned four-coil electric energy direction-changing wireless enhanced transmission device based on metamaterials, and the method comprises:

[0014] S1, determine the distances between the transmitting coil, the transmitting end excitation coil, the receiving coil and the receiving end excitation coil when the transmission efficiency is maximum according to experimental comparison;

[0015] S2, the shape of the metamaterial coil array when the quality factor is maximum calculated by the particle swarm optimization algorithm;

[0016] S3, since electromagnetic waves will be refracted when entering the metamaterial coil array, according to the relationship between the incident angle, the reflection angle and the equivalent magnetic permeability, the position relationship between the transmitting coil, the receiving coil and the metamaterial coil array when the equivalent magnetic permeability is maximum is determined;

[0017] S4, based on the relationship between the external capacitance and the equivalent magnetic permeability, the value of the external capacitance when the equivalent magnetic permeability is maximum is obtained through simulation software.

[0018] The embodiment of the present invention further provides a network side server, including:

[0019] At least one processor; and a memory in communication with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the above-mentioned four-coil electric energy redirection wireless enhanced transmission method based on metamaterials.

[0020] An embodiment of the present invention further provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the above-mentioned four-coil electric energy redirection wireless enhanced transmission method based on metamaterials.

[0021] The beneficial effects of the present invention are as follows: the four-coil electric energy directional wireless enhanced transmission method based on metamaterials of the present invention comprises a high-frequency power supply, a transmitting coil connected to the high-frequency power supply, a receiving coil, a metamaterial coil array arranged between the transmitting coil and the receiving coil, an external capacitor connected to the metamaterial coil array, and a load connected to the receiving coil, the metamaterial coil array comprises three groups of first metamaterial coils, three groups of second metamaterial coils, and three groups of third metamaterial coils, a total of nine groups of metamaterial coils are arranged to form a square, and the spacing between two adjacent metamaterial coils is equal, the nine groups of metamaterial coils are all arranged on an FR4 substrate, the transmitting coil and the receiving coil are arranged vertically, and the metamaterial coil array is arranged on the angular bisector of the transmitting coil and the receiving coil. The four-coil electric energy redirection wireless enhanced transmission device based on metamaterials of the present invention improves the receiving efficiency of the receiving coil by changing the external capacitance value of the metamaterial coil array when the positions of the transmitting coil, the receiving coil and the metamaterial coil array are fixed. The control method is simple and adaptable to different application scenarios. By placing the metamaterial coil array at a preset position, the direction of wireless power transmission can be changed. By changing the position of the excitation coil, the accuracy of the redirection transmission and the transmission power are improved. The distance between the transmitting end excitation coil and the transmitting coil can be adjusted to maximize the system transmission power. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0023] In the figure:

[0024] Figure 1 A schematic diagram of the structure of a four-coil electric energy redirection wireless enhanced transmission device based on metamaterials provided in Embodiment 1 of the present invention;

[0025] Figure 2 A schematic diagram of the structure of a metamaterial coil array provided in Embodiment 1 of the present invention;

[0026] Figure 3 A schematic diagram of the structure of a group of metamaterial coils provided in Embodiment 1 of the present invention;

[0027] Figure 4 A schematic diagram of the incident angle and refraction angle of an electromagnetic wave passing through a metamaterial provided in the first embodiment of the present invention;

[0028] Figure 5 A schematic diagram of the positions of a transmitting coil, a receiving coil, an excitation coil and a metamaterial coil array provided in the first embodiment of the present invention;

[0029] Figure 6 A curve diagram showing the change between the magnetic permeability and the external capacitance provided in the first embodiment of the present invention;

[0030] Figure 7 A line graph showing changes in the angle between the metamaterial coil array and the transmitting coil and the receiving coil and the amplitude of the receiving coil when the external capacitance remains unchanged, provided in the first embodiment of the present invention;

[0031] Figure 8 This is an energy simulation diagram provided by the first embodiment of the present invention when the metamaterial coil array is not introduced;

[0032] Fig. 9 An energy simulation diagram when a metamaterial coil array is introduced according to the first embodiment of the present invention;

[0033] Fig.10 A flow chart of a four-coil electric energy redirection wireless enhanced transmission method based on metamaterials provided in the second embodiment of the present invention;

[0034] Fig.11 It is a structural diagram of a network-side server provided according to a third embodiment of the present invention.

[0035] Among them, the reference numerals in the figure are:

[0036] High frequency power supply 1;

[0037] Transmitting coil 2, first resonant capacitor 21, transmitting end excitation coil 22, second resonant capacitor 23;

[0038] Receiving coil 3, third resonant capacitor 31, receiving end excitation coil 32, fourth resonant capacitor 33;

[0039] Metamaterial coil array 4, first metamaterial coil 41, second metamaterial coil 42, third metamaterial coil 43;

[0040] Load 5. DETAILED DESCRIPTION

[0041] It should be mentioned before discussing the exemplary embodiments in more detail that some exemplary embodiments are described as processes or methods depicted as flow charts. Although the flow charts describe the operations as sequential processes, many of the operations therein can be implemented in parallel, concurrently or simultaneously. In addition, the order of the operations can be rearranged. The process can be terminated when its operation is completed, but can also have additional steps not included in the accompanying drawings. The process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0042] It should be understood that, although the terms "first", "second", etc. may be used herein to describe various units, these units should not be limited by these terms. These terms are used only to distinguish one unit from another unit. For example, without departing from the scope of the exemplary embodiments, the first unit may be referred to as the second unit, and similarly the second unit may be referred to as the first unit. The term "and / or" used herein includes any and all combinations of one or more of the listed associated items.

[0043] The present invention will now be described in detail with reference to the accompanying drawings. This figure is a simplified schematic diagram, which only illustrates the basic structure of the present invention in a schematic manner, and therefore only shows the components related to the present invention.

[0044] First embodiment:

[0045] like Figure 1 As shown, a schematic diagram of a four-coil electric energy redirection wireless enhanced transmission device 100 based on metamaterials of the present invention.

[0046] As an example, the four-coil electric energy redirection wireless enhanced transmission device 100 based on metamaterial includes: a high-frequency power supply 1, a transmitting coil 2 connected to the high-frequency power supply 1, a receiving coil 3, a metamaterial coil array 4 arranged between the transmitting coil 2 and the receiving coil 3, an external capacitor connected to the metamaterial coil array 4, and a load 5 connected to the receiving coil 3.

[0047] Specifically, the high-frequency power supply 1 generates a high-frequency alternating current with a frequency of 6 MHz. The transmitting coil 2 and the receiving coil 3 have the same structure, and both the transmitting coil 2 and the receiving coil 3 have a cross-sectional area of ​​0.491 m 2 The excitation wire is wound to form a circular coil with a diameter of 34 cm and 6 turns. A first resonant capacitor 21 is also provided at one end of the transmitting coil 2, and the high-frequency power supply 1 is connected in series with the transmitting coil 2 and the first resonant capacitor 21 to generate wireless power with a resonant frequency. A third resonant capacitor 31 is also provided at one end of the receiving coil 3, and the load 5 is connected in series with the receiving coil 3 and the third resonant capacitor 31 to sense magnetic field energy and convert the magnetic field energy into electrical energy to power the load 5.

[0048] As an example, a transmitting end excitation coil 22 is also provided on one side of the transmitting coil 2. The transmitting end excitation coil 22 is provided on the side of the transmitting coil 2 close to the metamaterial coil array 4, the transmitting end excitation coil 22 is parallel to the transmitting coil 2, a second resonant capacitor 23 is provided at one end of the transmitting end excitation coil 22, and the second resonant capacitor 23 is connected in series with the transmitting end excitation coil 22. A receiving end excitation coil 32 is also provided on one side of the receiving coil 3. The receiving end excitation coil 32 is provided on the side of the transmitting coil 2 close to the metamaterial coil array 4, the receiving end excitation coil 32 is parallel to the receiving coil 3, a fourth resonant capacitor 33 is provided at one end of the receiving end excitation coil 32, and the receiving fourth resonant capacitor 33 is connected in series with the receiving end excitation coil 32.

[0049] If the excitation coil is not added, the power is low. After the excitation coil is added, the power is significantly improved, as shown in Table 1. d1 is the distance between the transmitting coil 2 and the receiving coil 3. The distance between the transmitting coil 2 and the transmitting end excitation coil 22 is 6 cm, and the distance between the receiving coil 3 and the receiving end excitation coil 32 is 6 cm.

[0050] Table 1 Comparison of amplitudes of double coils and four coils

[0051]

[0052] When the metamaterial coil array 4 is not added, the distance between the fixed receiving coil 3 and the receiving end excitation coil 32 is 6 cm, as shown in Table 2, so that the distance between the transmitting coil 2 and the transmitting end excitation coil is equal, and the amplitude of the receiving coil is compared in the two cases of fixed transmitting coil 2 and moving the transmitting end excitation coil 22 and fixed transmitting end excitation coil 22 and moving the transmitting coil 2. In Table 2, d is the distance between the transmitting coil 2 and the transmitting end excitation coil 22, f1 is the amplitude of the receiving coil 3 when the transmitting coil 2 is fixed, and f2 is the amplitude of the receiving coil 3 when the transmitting end excitation coil 22 is fixed.

[0053] Table 2 Comparison of transmission efficiency of two mobile modes

[0054]

[0055] It can be seen from Table 2 that when the transmitting coil 2 is fixed and the transmitting end exciting coil 22 is moved, the amplitude of the receiving end is larger and the effect is better.

[0056] When the transmitting coil 2 and the receiving coil 3 are facing each other, the distance d between the transmitting coil 2 and the receiving coil 3 is fixed to 20 cm. After adding the transmitting end excitation coil 22 and the receiving end excitation coil 32, the distance d between the transmitting end excitation coil 22 and the transmitting coil 2 is changed. 12 It is found that when the distance between the transmitting coil 2 and the transmitting end excitation coil 22 is 6 cm, the receiving coil amplitude is the largest, that is, the optimal distance is 6 cm.

[0057] Table 3 Relationship between the distance and amplitude between the transmitting coil 2 and the transmitting end excitation coil 22

[0058]

[0059] Therefore, in this embodiment, the distance between the transmitting coil 2 and the transmitting end excitation coil 22 is 6 cm, and the distance between the receiving coil 3 and the receiving end excitation coil 32 is 6 cm. The structures of the transmitting end excitation coil 22 and the receiving end excitation coil 32 are the same, and both the transmitting end excitation coil 22 and the receiving end excitation coil 32 have a cross-sectional area of ​​0.491 mm 2 The excitation wire is wound to form a circular coil with a diameter of 34 cm and 6 turns.

[0060] The particle swarm optimization algorithm is used to determine the shape by the size of the quality factor when the metamaterial is square, circular, hexagonal, and octagonal. It is found that when the metamaterial plate is square, the quality factor Q is the largest, and the square is selected among different metamaterial shapes. Using the particle swarm algorithm (SO), the quality factor Q of the metamaterial plate is used as the objective function to find the outer diameter, inner diameter, line width, turn spacing, and number of turns of the metamaterial plate when the Q value is maximum. As a preferred embodiment of the present invention, the metamaterial coil array 4 includes a plurality of metamaterial coils of the same shape arranged at equal distances between each other to form a square array. By adjusting the number of metamaterial coils, different transmission requirements can be met.

[0061] like Figure 2 , Figure 3 As shown, as an example, the metamaterial coil array 4 includes three groups of first metamaterial coils 41, three groups of second metamaterial coils 42 and three groups of third metamaterial coils 43, a total of nine groups of metamaterial coils are arranged to form a square, and the spacing between two adjacent metamaterial coils is equal, the distance between the outer diameters of two adjacent metamaterial coils is 5 mm, and the nine groups of metamaterial coils are all arranged on the FR4 substrate.

[0062] As an example, Figure 4As shown, when electromagnetic waves enter negative magnetic permeability metamaterials from traditional dielectric materials, negative refraction occurs, that is, the incident direction and the reflection direction are on the same side of the normal. The relationship between the incident angle, reflection angle and magnetic permeability is:

[0063]

[0064] Among them, θ1 is the incident angle, θ2 is the refraction angle (θ2<0), and μ1 and μ2 are the equivalent magnetic permeabilities of different materials on both sides of the interface.

[0065] like Figure 5 As shown, since the energy transmission direction is changed after adding the metamaterial coil array 4 in this embodiment, the energy will be transmitted to the receiving coil along the dotted line in the figure. When the energy transmission direction is perpendicular to the receiving coil 4, that is, according to the relationship between the incident angle, the reflection angle and the equivalent magnetic permeability, when the refraction angle θ a '=θ b '=θ c When '=-45°, the receiving efficiency of the receiving coil 4 is the highest; wherein the relative magnetic permeability of the air is 1. According to the relationship formula between the incident angle, the reflection angle and the equivalent magnetic permeability, at this time, the relationship formula between the incident angle, the reflection angle and the equivalent magnetic permeability is:

[0066] θ1=arctan(tanθ2 / μ2)

[0067] Where μ2 is the equivalent magnetic permeability of the metamaterial coil array, θ1 is the incident angle, and θ2 is the refraction angle.

[0068] Since the average energy transmission direction of the transmitting coil 3 is incident at angles θ to the first metamaterial coil 7, the second metamaterial coil 8 and the third metamaterial coil 9 respectively a ,θ b and θ c , considering the symmetry and divergence of the magnetic field generated by the transmitting coil, the angle relationship should conform to the following formula:

[0069] |θ c -θ b |>|θ b -θ a |

[0070] It can be seen that the central magnetic field of the transmitting coil 3 is perpendicular to the plane of the transmitting coil 3 and directly points to the second metamaterial coil 42, so θ b The ideal value of ' should be 45°.

[0071] As an example, the transmitting coil 2 is vertically arranged with the receiving coil 3, and the distance from the intersection of the extended lines of the transmitting coil 2 and the receiving coil 3 to the edge of the transmitting coil 2 near the intersection is 8 cm, and the distance from the intersection of the extended lines of the transmitting coil 2 and the receiving coil 3 to the edge of the receiving coil 3 near the intersection is 8 cm. The metamaterial coil array 4 is arranged on the angular bisector of the transmitting coil 2 and the receiving coil 3, and the line between the center of the metamaterial coil array 4 and the center of the transmitting coil 2 is perpendicular to the transmitting coil 2; the line between the center of the metamaterial coil array 4 and the center of the receiving coil 3 is perpendicular to the receiving coil 3.

[0072] As an example, the number of external capacitors is equal to the number of metamaterial coils. Each group of metamaterial coils is also connected in series with an external capacitor C0 (not shown in the figure). The FR4 substrate is a square, and one side of the FR4 substrate is a copper wire wound in three spiral circles as a group of metamaterial coils. There are two through holes at the joint of the copper wire of each group of metamaterial coils, and the through holes connect the front and back of the substrate. The external capacitor is welded on the other side of the FR4 substrate through the two through holes, and the nine groups of metamaterial coils are connected in series end to end through multiple external capacitors.

[0073] The side length d of the FR4 substrate FR4 The square metamaterial coil is set on the FR4 substrate through the etching process, and the copper wire thickness is t co 0.035mm; the outer diameter of the outermost copper wire d out The inner diameter of the innermost copper wire is d in It is 55mm, the spacing s between two coil turns is 2mm, the copper wire width w is 2mm, the number of turns is 8, the vertical distance between the copper wire joints is l=4mm, and the distance between the two copper wire joints and the inner diameter of the outermost copper wire is l1=l2.

[0074] When the size of the external capacitor C0 changes, the magnetic permeability of the metamaterial coil will change accordingly, and the magnetic permeability of the array composed of metamaterial coils will also change synchronously. The metamaterial coil array model is established in the HFSS software, and the reflection coefficient S corresponding to the model can be obtained through simulation. 11 and the transmission coefficient S 21 ; Then the calculation formula of the refractive index n and wave impedance z of the metamaterial coil array is:

[0075]

[0076] Where z is the wave impedance, S 11 is the reflection coefficient, S 21 is the transmission coefficient, n is the refractive index, k is the wave vector, k = f / c, f is the system operating frequency, c is the speed of light; t co is the thickness of the copper wire, t co=0.035mm.

[0077] The equivalent magnetic permeability formula is:

[0078] μ2=n*z

[0079] Among them, μ2 is the equivalent magnetic permeability, n is the refractive index, and z is the wave impedance.

[0080] Therefore, by changing the size of the external capacitor C0, the magnetic permeability of the equivalent metamaterial coil array under different capacitances can be simulated, that is, Figure 5 .

[0081] like Figure 6 As shown, a curve diagram of the change of magnetic permeability with respect to the external capacitor C0 and the equivalent magnetic permeability μ2 is obtained; since there is a corresponding relationship between the incident angle and the magnetic permeability, a curve of the change of the incident angle with respect to the external capacitor C0 can be obtained.

[0082] like Figure 1 As shown, θ b The value closest to 45° should be selected, and 182 pF is selected as the size C0 of the external capacitance of the second metamaterial coil 42; considering the incident angle θ a ,θ b and θ c , 178 pF and 188 pF are selected as the external capacitance of the first metamaterial coil 41 and the third metamaterial coil 43 respectively. The relationship between the external capacitance and its corresponding angle is shown in Table 4.

[0083] Table 4 External capacitor size and its corresponding angle relationship

[0084]

[0085] By adjusting the angle θ between the metamaterial coil array 4 and the transmitting coil 2 and the receiving coil 3, when C0 remains unchanged, it is found through experimental comparison that Figure 5 As shown, when θ=45°, the transmission efficiency is maximum.

[0086] Metamaterial coils with different magnetic permeabilities have different deflection angles for the magnetic field. The above method is used to accurately configure parameters and deflect magnetic fields in different directions to the direction of the receiving coil.

[0087] The present invention can improve the transmission power when the transmitting coil 2 and the receiving coil 3 are perpendicular to each other in the coal mine. Compared with the case where the directional metamaterial coil array 4 is not placed, the receiving power of the load is significantly improved, and has good practical value.

[0088] When θ=45°, the wireless energy flows vertically to the receiving coil 4, and the receiving power of the receiving coil 4 is the maximum. Figure 7As shown, when the external capacitor C0 is constant, the horizontal axis is the change value of the angle θ, and the vertical axis is the received power value. It can be concluded that the power is maximum when θ=45°.

[0089] like Fig.10 and Fig.11 The figures are comparison diagrams of magnetic field simulation effects with and without the metamaterial coil array. It can be seen that the magnetic field energy of the receiving coil 4 after adding the metamaterial coil array is significantly better than that without the metamaterial coil array.

[0090] The four-coil electric energy redirection wireless enhanced transmission device based on metamaterials of the present invention comprises: a high-frequency power supply 1, a transmitting coil 2 connected to the high-frequency power supply 1, a receiving coil 3, a metamaterial coil array 4 arranged between the transmitting coil 2 and the receiving coil 3, an external capacitor connected to the metamaterial coil array 4, and a load 5 connected to the receiving coil 3. When the positions of the transmitting coil 2, the receiving coil 3 and the metamaterial coil array 4 are fixed, the equivalent magnetic permeability value of the refraction direction of the metamaterial coil array 4 is changed by changing the external capacitor value of the metamaterial coil array 4, so that the receiving efficiency of the receiving coil 3 is improved. The control method is simple and adaptable to different application scenarios. By placing the metamaterial coil array at a preset position, the direction of wireless power transmission can be changed. By changing the position of the excitation coil, the accuracy of the redirection transmission and the transmission power are improved. When the angle between the receiving coil 3 and the transmitting coil 2 changes, the metamaterial coil array 4 can be redesigned according to the embodiment of the present invention to deflect the energy to other directions. It is possible to adjust the distance between the transmitting end excitation coil 22 and the transmitting coil 2, and the system transmission power is maximized by determining the optimal distance.

[0091] Second implementation method:

[0092] like Fig.10 As shown, a flow chart of a four-coil electric energy redirection wireless enhanced transmission method based on metamaterials proposed by the present invention.

[0093] As an example, the four-coil electric energy redirection wireless enhanced transmission method based on metamaterials includes:

[0094] Step S1, determining the distances between the transmitting coil, the transmitting end excitation coil, the receiving coil and the receiving end excitation coil when the transmission efficiency is maximum according to experimental comparison.

[0095] In this embodiment, when the metamaterial coil array is not added, the preset distance between the fixed receiving coil 3 and the receiving end excitation coil 32 is 6 cm, as shown in Table 2, so that the distance between the transmitting coil and the transmitting end excitation coil is equal, and the amplitude of the receiving coil is compared in the two cases of the fixed transmitting coil moving the transmitting end excitation coil and the fixed transmitting end excitation coil moving the transmitting coil. It can be seen from Table 2 that the amplitude of the receiving end is larger and the effect is better when the fixed transmitting coil moves the transmitting end excitation coil. When the transmitting coil and the receiving coil are facing each other, the distance d between the fixed transmitting coil 2 and the receiving coil 3 is 20 cm. After adding the transmitting end excitation coil and the receiving end excitation coil, the distance d between the transmitting end excitation coil and the transmitting coil 2 is changed. 12 ,It can be seen from Table 3 that when the distance between the transmitting coil and the transmitting end excitation coil is 6cm, the amplitude of the receiving coil is the largest, that is, the optimal distance is 6cm.

[0096] Therefore, when the preset distance between the receiving coil and the receiving end excitation coil is 6 cm, and the distance between the transmitting coil and the transmitting end excitation coil is 6 cm, the transmission efficiency is maximum.

[0097] Step S2, calculating the shape of the metamaterial coil array when the quality factor is maximum according to the particle swarm optimization algorithm.

[0098] Specifically, the particle swarm optimization algorithm is used to determine the shape by finding the size of the quality factor when the metamaterial is square, circular, hexagonal, or octagonal. It is found that when the metamaterial plate is square, the quality factor Q is the largest, and a square is selected among different metamaterial shapes. Using a particle swarm algorithm (SO), the quality factor Q of the metamaterial plate is used as the objective function to find the outer diameter, inner diameter, line width, turn spacing, and number of turns of the metamaterial plate when the Q value is maximum. As a preferred embodiment of the present invention, the metamaterial coil array 4 includes a plurality of metamaterial coils of the same shape arranged at equal distances between each other to form a square array. By adjusting the number of metamaterial coils, different transmission requirements can be met.

[0099] In this embodiment, the metamaterial coil array includes three groups of first metamaterial coils 41, three groups of second metamaterial coils and three groups of third metamaterial coils. A total of nine groups of metamaterial coils are arranged to form a square, and the spacing between two adjacent metamaterial coils is equal. The distance between the outer diameters of two adjacent metamaterial coils is 5 mm. The nine groups of metamaterial coils are all arranged on a FR4 substrate.

[0100] Step S3, since electromagnetic waves will be refracted when entering the metamaterial coil array, the position relationship of the transmitting coil, the receiving coil and the metamaterial coil array when the equivalent magnetic permeability is maximum is determined according to the relationship between the incident angle, the reflection angle and the equivalent magnetic permeability.

[0101] Specifically, when electromagnetic waves enter negative permeability metamaterials from traditional dielectric materials, negative refraction occurs, that is, the incident direction and the reflection direction are on the same side of the normal. The relationship between the incident angle, reflection angle and magnetic permeability is:

[0102]

[0103] Among them, θ1 is the incident angle, θ2 is the refraction angle (θ2<0), and μ1 and μ2 are the equivalent magnetic permeabilities of different materials on both sides of the interface.

[0104] In this embodiment, since the energy transmission direction is changed after adding the metamaterial coil array, the energy will be transmitted to the receiving coil along the dotted line in the figure. When the energy transmission direction is perpendicular to the receiving coil, that is, according to the relationship between the incident angle, the reflection angle and the equivalent magnetic permeability, when the refraction angle θ a '=θ b '=θ c When '=-45°, the receiving efficiency of the receiving coil is the highest; the relative magnetic permeability of the air is 1. According to the relationship formula between the incident angle, reflection angle and equivalent magnetic permeability, at this time, the relationship formula between the incident angle, reflection angle and equivalent magnetic permeability is:

[0105] θ1=arctan(tanθ2 / μ2)

[0106] Where μ2 is the equivalent magnetic permeability of the metamaterial coil array, θ1 is the incident angle, and θ2 is the refraction angle.

[0107] Since the average energy transmission direction of the transmitting coil 3 is incident at angles θ to the first metamaterial coil 7, the second metamaterial coil 8 and the third metamaterial coil 9 respectively a ,θ b and θ c , considering the symmetry and divergence of the magnetic field generated by the transmitting coil, the angle relationship should conform to the following formula:

[0108] |θ c -θ b |>|θ b -θ a |

[0109] It can be seen that the magnetic field at the center of the transmitting coil is perpendicular to the plane of the transmitting coil and directly points to the second metamaterial coil, so θ b The ideal value of ' should be 45°.

[0110] Therefore, the transmitting coil and the receiving coil are arranged vertically, and the distance from the intersection of the extended lines of the transmitting coil and the receiving coil to the edge of the transmitting coil near the intersection is 8 cm, and the distance from the intersection of the extended lines of the transmitting coil and the receiving coil 3 to the edge of the receiving coil 3 near the intersection is 8 cm. The metamaterial coil array is arranged on the angular bisector of the transmitting coil and the receiving coil, and the line between the center of the metamaterial coil array and the center of the transmitting coil is perpendicular to the transmitting coil; the line between the center of the metamaterial coil array and the center of the receiving coil is perpendicular to the receiving coil.

[0111] Step S4, according to the relationship between the external capacitance and the equivalent magnetic permeability, the value of the external capacitance when the equivalent magnetic permeability is maximum is obtained through simulation software.

[0112] Specifically, when the size of the external capacitor C0 changes, the magnetic permeability of the metamaterial coil will change accordingly, and the magnetic permeability of the array composed of metamaterial coils will also change synchronously. The metamaterial coil array model is established in the HFSS software, and the reflection coefficient S corresponding to the model can be obtained through simulation. 11 and the transmission coefficient S 21 ; Then the calculation formula of the refractive index n and wave impedance z of the metamaterial coil array is:

[0113]

[0114] Where z is the wave impedance, S 11 is the reflection coefficient, S 21 is the transmission coefficient, n is the refractive index, k is the wave vector, k = f / c, f is the system operating frequency, c is the speed of light; t co is the thickness of the copper wire, t co =0.035mm.

[0115] The equivalent magnetic permeability formula is:

[0116] μ2=n*z

[0117] Among them, μ2 is the equivalent magnetic permeability, n is the refractive index, and z is the wave impedance.

[0118] Therefore, by changing the size of the external capacitor C0, the magnetic permeability of the equivalent metamaterial coil array under different capacitances can be simulated, that is, Figure 5 .

[0119] like Figure 6 As shown, a curve diagram of the change of magnetic permeability with respect to the external capacitor C0 and the equivalent magnetic permeability μ2 is obtained; since there is a corresponding relationship between the incident angle and the magnetic permeability, a curve of the change of the incident angle with respect to the external capacitor C0 can be obtained.

[0120] like Figure 7 As shown, θb The value closest to 45° should be selected, and 182 pF is selected as the size C0 of the external capacitance of the second metamaterial coil 42; considering the incident angle θ a ,θ b and θ c , 178pF and 188pF are selected as the external capacitance of the first metamaterial coil and the third metamaterial coil respectively. The external capacitance and its corresponding angle relationship are shown in Table 4. When the angle θ between the metamaterial coil array and the transmitting coil and the receiving coil is adjusted and C0 remains unchanged, it is obtained through experimental comparison that Figure 7 As shown, when θ=45°, the transmission efficiency is maximum.

[0121] Metamaterial coils with different magnetic permeabilities have different deflection angles for the magnetic field. The above method is used to accurately configure parameters and deflect magnetic fields in different directions to the direction of the receiving coil.

[0122] When θ = 45°, the wireless energy flows vertically to the receiving coil, and the receiving power of the receiving coil is the maximum. Fig. 9 As shown, when the external capacitor C0 is constant, the horizontal axis is the change value of the angle θ, and the vertical axis is the received power value. It can be concluded that the power is maximum when θ=45°.

[0123] Third embodiment:

[0124] A third embodiment of the present invention provides a network side server, such as Fig.11 As shown, it includes at least one processor 301; and a memory 302 that is communicatively connected to the at least one processor 301; wherein the memory 302 stores commands that can be executed by at least one processor 301, and the instructions are executed by at least one processor 301, so that at least one processor 301 can execute the above-mentioned data processing method.

[0125] The memory 302 and the processor 301 are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors 301 and the memory 302 together. The bus can also connect various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor 301 is transmitted on a wireless medium through an antenna, and further, the antenna also receives data and transmits the data to the processor 301.

[0126] The processor 301 is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management and other control functions. The memory 302 can be used to store data used by the processor 301 when performing operations.

[0127] Fourth embodiment:

[0128] The fourth embodiment of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the four-coil power redirection wireless enhanced transmission method based on metamaterials in the first embodiment.

[0129] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including several instructions to enable a device (which can be a single-chip microcomputer, chip, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0130] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

[0131] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A four-coil electric energy redirection wireless enhanced transmission device based on metamaterials, characterized in that: include: A high-frequency power supply, a transmitting coil connected to the high-frequency power supply, a receiving coil, a metamaterial coil array arranged between the transmitting coil and the receiving coil, an external capacitor connected to the metamaterial coil array, and a load connected to the receiving coil, the metamaterial coil array includes three groups of first metamaterial coils, three groups of second metamaterial coils, and three groups of third metamaterial coils, a total of nine groups of metamaterial coils are arranged to form a square, and the spacing between two adjacent metamaterial coils is equal, the nine groups of metamaterial coils are all arranged on an FR4 substrate, the transmitting coil is arranged perpendicular to the receiving coil, and the metamaterial coil array is arranged on the angular bisector of the transmitting coil and the receiving coil.

2. The four-coil electric energy redirection wireless enhanced transmission device based on metamaterials according to claim 1 is characterized in that: The high-frequency power supply generates a high-frequency alternating current with a frequency of 6 MHz. The transmitting coil 2 and the receiving coil have the same structure. The transmitting coil and the receiving coil both have a cross-sectional area of ​​0.491 mm 2 The excitation wire is wound to form a circular coil with a diameter of 34 cm and 6 turns.

3. The four-coil electric energy redirection wireless enhanced transmission device based on metamaterials according to claim 1 is characterized in that: A first resonant capacitor is disposed at one end of the transmitting coil, and the high-frequency power supply is connected in series with the transmitting coil and the first resonant capacitor to generate wireless power with a resonant frequency.

4. The four-coil power energy redirection wireless enhanced transmission device based on metamaterials according to claim 1 is characterized in that: A third resonant capacitor is also provided at one end of the receiving coil, and the load is connected in series with the receiving coil and the third resonant capacitor for sensing magnetic field energy and converting the magnetic field energy into electrical energy to supply power to the load.

5. The four-coil power energy redirection wireless enhanced transmission device based on metamaterials according to claim 1 is characterized in that: A transmitting end excitation coil is arranged on one side of the transmitting coil, the transmitting end excitation coil is arranged on a side of the transmitting coil close to the metamaterial coil array, the transmitting end excitation coil is parallel to the transmitting coil, a second resonant capacitor is arranged at one end of the transmitting end excitation coil, and the second resonant capacitor is connected in series with the transmitting end excitation coil.

6. The four-coil electric energy redirection wireless enhanced transmission method based on metamaterials according to claim 1 is characterized in that: A receiving end excitation coil is arranged on one side of the receiving coil, and the receiving end excitation coil is arranged on a side of the transmitting coil close to the metamaterial coil array. The receiving end excitation coil is parallel to the receiving coil, and a fourth resonant capacitor is arranged at one end of the receiving end excitation coil, and the fourth resonant capacitor is connected in series with the receiving end excitation coil.

7. The four-coil power energy redirection wireless enhanced transmission device based on metamaterials according to claim 1 is characterized in that: The number of the external capacitors is equal to the number of groups of metamaterial coils, each group of metamaterial coils is respectively connected to the external capacitor C0, the FR4 substrate is a square, one side of the FR4 substrate is a copper wire wound with three spiral circles of a square as a group of metamaterial coils, and there are two through holes at the joints of the copper wires of each group of metamaterial coils, the through holes connect the front and back sides of the FR4 substrate, and the external capacitors are welded to the other side of the FR4 substrate through the two through holes, and the nine groups of metamaterial coils are connected in series end to end through multiple external capacitors.

8. A four-coil electric energy redirection wireless enhanced transmission method based on metamaterials, characterized in that: The method applied to the metamaterial-based four-coil electric energy redirection wireless enhanced transmission device in claim 1 comprises: S1, determine the distances between the transmitting coil, the transmitting end excitation coil, the receiving coil and the receiving end excitation coil when the transmission efficiency is maximum according to experimental comparison; S2, the shape of the metamaterial coil array when the quality factor is maximum calculated by the particle swarm optimization algorithm; S3, since electromagnetic waves will be refracted when entering the metamaterial coil array, according to the relationship between the incident angle, the reflection angle and the equivalent magnetic permeability, the position relationship between the transmitting coil, the receiving coil and the metamaterial coil array when the equivalent magnetic permeability is maximum is determined; S4, based on the relationship between the external capacitance and the equivalent magnetic permeability, the value of the external capacitance when the equivalent magnetic permeability is maximum is obtained through simulation software.

9. A network side server, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the four-coil power directional wireless enhanced transmission method based on metamaterials as claimed in any one of claim 8.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the four-coil electric energy redirection wireless enhanced transmission method based on metamaterials as claimed in any one of claim 8 is implemented.

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