A truncated cone type UAV wireless charging device based on a bipolar transmitting coil

Abstract

The invention discloses a truncated cone type unmanned aerial vehicle wireless charging device based on a bipolar transmitting coil, which belongs to the technical field of magnetically coupled wireless power transmission, and aims to solve the problem that when a truncated cone type unmanned aerial vehicle is wirelessly charged, the coupling coefficient between a transmitting coil and a receiving coil is not high, which affects the wireless charging efficiency of the unmanned aerial vehicle. The invention comprises a ray coil comprising two trapezoidal coils of different sizes and opposite winding directions, the two trapezoidal coils are curled along the circumference so that the two oblique sides are close to each other and form a truncated cone shape, and are distributed in two close sections along the truncated cone inclined surface, the receiving coil is a spiral tube coil, and the tube core line of the receiving coil is parallel to the truncated cone inclined surface generatrix along which the transmitting coil is located, so that when the transmitting coil is coupled with the transmitting coil in this way, it is beneficial to provide a higher coupling coefficient, the lack of a magnetic field has a smaller effect on the mutual inductance, the mutual inductance fluctuation rate is reduced when the unmanned aerial vehicle rotates and deviates, and the wireless charging efficiency of the unmanned aerial vehicle is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetically coupled wireless power transmission, and more specifically, particularly relates to a truncated cone type unmanned aerial vehicle wireless charging device based on a bipolar transmitting coil. Background Art

[0002] Modern drones, represented by multi-rotor drones, have been widely used in civil and military fields, so the endurance of drones has become very critical. At present, there are three main solutions to solve the endurance problem of drones, namely, carrying solar cells, using base station manipulators to replace batteries, and contact charging platforms. All three solutions have problems to a certain extent, including that small and medium-sized drones cannot carry solar cells for endurance due to their small wings, and using base stations to replace batteries requires the modification of drones and precise control equipment. Contact charging is prone to aging and wear and short circuits due to exposed contacts. Therefore, in order to solve these problems and improve the endurance of drones, one or more wireless charging platforms are configured in the drone application route based on wireless power transmission technology. This method greatly compensates for the cruising distance problem caused by the insufficient endurance of drones, and also realizes unmanned and intelligent operation.

[0003] After a long period of development, the wireless charging technology for drones has good output characteristics. In most drone charging devices, the receiving coil is generally located on the bottom tripod to obtain better coupling characteristics; the transmitting coil is generally on a disc-shaped landing platform. However, due to the instability of drone landing, this type of drone wireless charging device requires extremely strong anti-lateral deviation capabilities. When the lateral deviation is large, it usually causes large mutual inductance fluctuations. Among them, drones with circular chassis, such as Figure 6 The truncated cone type wireless charging device shown can help it to complete automatic alignment, so that the lateral displacement of the UAV after landing is very small, so that it can obtain greater transmission power and transmission efficiency. However, this method has the problem that the coupling between the transmitting coil and the receiving coil is not strong, and the coupling coefficient needs to be further improved, which affects the efficiency of wireless charging of the UAV. Therefore, in order to improve the coupling coefficient between the transmitting coil and the receiving coil, the present invention provides a technical solution. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a truncated cone type UAV wireless charging device based on a bipolar transmitting coil to solve the technical problem in the prior art that, when the truncated cone type UAV is wirelessly charged, the coupling coefficient between the transmitting coil and the receiving coil is not high, which affects the wireless charging efficiency of the UAV.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a truncated cone type UAV wireless charging device based on a bipolar transmitting coil, comprising a transmitting coil arranged on a charging platform and a receiving coil arranged on a UAV, characterized in that: the transmitting coil comprises two trapezoidal coils of different sizes and opposite winding directions, each trapezoidal coil is curled along the circumference so that the two oblique sides are close to each other and form a truncated cone shape, and the two trapezoidal coils are distributed in two sections along the truncated cone inclined surface, the receiving coil is a spiral tube coil, and the tube core line of the receiving coil is parallel to the generatrix of the truncated cone inclined surface along which the transmitting coil is located.

[0006] As a preferred technical solution of the present invention, the drone includes a body and a bracket, and the receiving coil is installed on the bracket.

[0007] As a preferred technical solution of the present invention, a plurality of the brackets are provided, and one receiving coil is arranged on each bracket.

[0008] As a preferred technical solution of the present invention, the brackets are arranged obliquely below the body and are evenly distributed around the circumference.

[0009] As a preferred technical solution of the present invention, a base frame is provided at the lower end of the bracket, and the base frame is arc-shaped, and its opening direction faces the central axis direction of the UAV.

[0010] As a preferred technical solution of the present invention, the receiving coil is a rectangular solenoid coil.

[0011] As a preferred technical solution of the present invention, a ferrite core is installed in the transmitting coil.

[0012] As a preferred technical solution of the present invention, the receiving coil has a size of 50*20*380 mm.

[0013] As a preferred technical solution of the present invention, the charging platform is in the shape of a truncated cone, and the transmitting coil is attached to the inclined surface wall of the charging platform.

[0014] As a preferred technical solution of the present invention, the area where the lower edge of the upper trapezoidal coil of the transmitting coil and the upper edge of the lower trapezoidal coil are located is an energy concentrated transmission area. When the drone is docked on the charging platform, the side of the receiving coil faces the energy concentrated transmission area.

[0015] The present invention provides a truncated cone type UAV wireless charging device based on a bipolar transmitting coil, which has the following beneficial effects:

[0016] 1. The transmitting coil can generate a target magnetic field upward along the truncated cone-shaped inclined surface. The core line of the receiving coil is parallel to the busbar of the truncated cone-shaped inclined surface along which the transmitting coil is connected. In this way, when the transmitting coil is coupled with the transmitting coil, it is beneficial to provide a higher coupling coefficient, and the lack of magnetic field has less effect on the mutual inductance, which reduces the mutual inductance fluctuation rate when the drone rotates and deviates, and improves the wireless charging efficiency of the drone.

[0017] 2. By setting up the arc-shaped chassis, the arc-shaped chassis can be limited when the drone is landing for charging, the landing accuracy requirements are reduced, and there will be no large lateral deviation during landing, which is convenient for guiding alignment and charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A three-dimensional diagram of a truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil according to the present invention;

[0019] Figure 2 A schematic diagram of magnetic field distribution in a truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to the present invention;

[0020] Figure 3 It is a schematic diagram of the unfolding of a receiving coil in a truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil according to the present invention;

[0021] Figure 4 It is a schematic diagram of the coordination of a transmitting coil and a receiving coil in a truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil according to the present invention;

[0022] Figure 5 A schematic diagram of the installation structure of a ferrite core in a truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil according to the present invention;

[0023] Figure 6 A schematic diagram of the structure of a wireless charging device in the prior art;

[0024] Figure 7 Experimental data of mutual inductance variation under rotational offset;

[0025] Figure 8 Experimental data on the change of mutual inductance under rotational offset;

[0026] Fig. 9 The experimental data of mutual inductance change when the receiving coil is 40*20*380 mm;

[0027] Fig.10 The experimental data of mutual inductance change when the receiving coil is 50*20*380 mm.

[0028] In the figure: 1, transmitting coil; 101, hypotenuse; 2, receiving coil; 3, drone; 301, body; 302, bracket; 303, chassis; 4, ferrite core; 5, magnetic lines of force. DETAILED DESCRIPTION

[0029] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0030] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" 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 an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] See also Figure 1 The present invention provides a technical solution, a truncated cone type UAV wireless charging device based on a bipolar transmitting coil: comprising a transmitting coil 1 arranged on a charging platform and a receiving coil 2 arranged on a UAV 3, characterized in that: the transmitting coil 1 comprises two coils of different sizes and opposite winding directions such as Figure 3 The trapezoidal coils shown in the figure are each curled along the circumference so that the two oblique sides 101 are close to each other and are like Figure 2 and Figure 4 The truncated cone is shown in the figure, and the two trapezoidal coils are distributed close to each other in two sections along the truncated cone slope, and the two transmitting coils 1 are connected in series, and the receiving coil 2 is a spiral tube coil, as shown in FIG. Figure 2 and Figure 4 The tube center line of the receiving coil 2 is shown to be parallel to the truncated cone-shaped inclined generatrix along which the transmitting coil 1 is arranged.

[0033] Among them, Figure 1 The drone 3 shown includes a body 301 and a bracket 302 , and the receiving coil 2 is mounted on the bracket 302 .

[0034] Among them, Figure 1 The bracket 302 shown is provided with a plurality of brackets, and a receiving coil 2 is provided on each bracket 302. When there are two receiving coils 2, relevant experimental data are obtained through experiments, where M1 and M2 represent the mutual inductance values ​​of the two receiving coils 2, respectively, as shown in FIG. Figure 7 As shown, under the influence of rotational offset, the total mutual inductance value of the entire coupling mechanism is about 5.04uH, and the mutual inductance fluctuation rate is 10.39%. It can be seen that under the current structure, the mutual inductance fluctuation caused by rotational offset is relatively high, and the total mutual inductance of the coupling mechanism itself is relatively small.

[0035] Among them, Figure 1 The brackets 302 are tilted and evenly distributed on the circumference below the body 301 .

[0036] Among them, Figure 1 As shown, a base frame 303 is provided at the lower end of the bracket 302 . The base frame 303 is arc-shaped, and its opening direction faces the central axis direction of the drone 3 .

[0037] Among them, Figure 4 Figure 5 The receiving coil 2 shown is a rectangular solenoid coil.

[0038] Among them, Figure 5 A ferrite core 4 is installed in the transmitting coil 1, and a better coupling effect and a rotation offset fluctuation mutual inductance suppression effect are obtained through the ferrite core 4. Through experiments, when the receiving coil is 60*10*380 mm, the number of turns is 30 turns, the truncated cone type transmitting coil 1 has a bottom radius of 6 cm, a top radius of 3 cm, a truncated cone thickness of 3.5 mm, the magnetic core is tightly attached to the transmitting coil 1, and the thickness is 5 mm, the following is obtained through experiments. Figure 8 From the experimental data shown, it can be found that the total mutual inductance fluctuation rate is about 8.09% under 360° rotation offset, and the mutual inductance value is about 11.6uH on average, which is much better than the effect when the ferrite core 4 is not added.

[0039] The size of the receiving coil 2 is 50*20*380 mm. Because the mutual inductance value and mutual inductance fluctuation rate will change accordingly when the receiving coil 2 has different sizes, the following results are obtained through experiments: Fig. 9 and Fig.10 The experimental results shown in FIG. 1 show that when the receiving coil 2 has a size of 40*20*380 mm, its mutual inductance value is about 13.89 uH on average, and the mutual inductance fluctuation rate is 10.12%. Fig. 9 As shown in the figure; when the size of the receiving coil 2 is 50*20*380 mm, its mutual inductance value is about 16.69uH on average, and the mutual inductance fluctuation rate is 9.05%, as shown in the figure Fig.10As shown in the figure, when the length of the receiving coil is less than 40 mm, the mutual inductance fluctuation rate is large and does not meet the wireless charging requirements of the drone 3. Therefore, after comprehensive consideration, a rectangular coil with a size of 50*20*380 mm is selected for the receiving coil 2.

[0040] The charging platform is in the shape of a truncated cone, and the transmitting coil 1 is attached to the inclined surface wall of the charging platform.

[0041] Among them, Figure 1 The area where the lower edge of the upper trapezoidal coil of the transmitting coil 1 and the upper edge of the lower trapezoidal coil are located is the energy concentrated transmission area. When the drone 3 is docked on the charging platform, the side of the receiving coil 2 faces the energy concentrated transmission area.

[0042] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil, comprising a transmitting coil (1) arranged on a charging platform and a receiving coil (2) arranged on an unmanned aerial vehicle (3), characterized in that: The transmitting coil (1) comprises two trapezoidal coils of different sizes and opposite winding directions, each of the trapezoidal coils is curled along the circumference so that the two oblique sides (101) are close to each other and form a truncated cone shape, and the two trapezoidal coils are distributed close to each other in two upper and lower sections along the truncated cone shaped inclined surface, the receiving coil (2) is a spiral tube coil, and the core line of the receiving coil (2) is parallel to the generatrix of the truncated cone shaped inclined surface along which the transmitting coil (1) is wound.

2. According to claim 1, the truncated cone type UAV wireless charging device based on the bipolar transmitting coil is characterized in that: The drone (3) comprises a body (301) and a bracket (302), and the receiving coil (2) is mounted on the bracket (302).

3. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 2 is characterized in that: A plurality of the supports (302) are provided, and a receiving coil (2) is arranged on each support (302).

4. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 3 is characterized in that: The brackets (302) are arranged obliquely below the machine body (301) and are evenly distributed around the circumference.

5. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 4 is characterized in that: A base frame (303) is arranged at the lower end of the bracket (302); the base frame (303) is arc-shaped, and its opening direction faces the central axis direction of the drone (3).

6. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to any one of claims 1 to 5, characterized in that: The receiving coil (2) is a rectangular solenoid coil.

7. The truncated cone type wireless charging device for unmanned aerial vehicles based on a bipolar transmitting coil according to any one of claims 1 to 5, characterized in that: A ferrite core (4) is installed in the transmitting coil (1).

8. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 6 is characterized in that: The receiving coil (2) has a size of 50*20*380 mm.

9. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 1, characterized in that: The charging platform is in the shape of a truncated cone, and the transmitting coil (1) is attached to the inclined surface wall of the charging platform.

10. The truncated cone type UAV wireless charging device based on a bipolar transmitting coil according to claim 1, characterized in that: The area where the lower edge of the upper trapezoidal coil of the transmitting coil (1) and the upper edge of the lower trapezoidal coil are located is an energy concentrated transmission area, and when the drone (3) is docked on the charging platform, the side of the receiving coil (2) faces the energy concentrated transmission area.

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