A double U-shaped magnetic coupling mechanism for wireless charging of a drone

Abstract

The utility model provides a kind of double U type magnetic coupling mechanism for unmanned aerial vehicle wireless charging, including being arranged on wireless charging platform transmitting end and being arranged on unmanned aerial vehicle fuselage receiving end;The transmitting end includes two U type magnetic cores arranged side by side, and transmitting end coil is wound on U type magnetic core;The receiving end includes receiving end coil wound on unmanned aerial vehicle fuselage, and receiving end coil is coupled with the shot end coil above transmitting end.This application provides a kind of double U type magnetic coupling mechanism for unmanned aerial vehicle wireless charging, because its receiving end is the rectangular hollow solenoid coil perpendicular to transmitting end magnetic core, the area of receiving to magnetic field is larger relative to plane coil, more energy can be obtained;In addition, the shape of receiving end coil is adapted to unmanned aerial vehicle fuselage, which can greatly reduce the volume of unmanned aerial vehicle, the hollow design of receiving end reduces the amount of ferrite, thereby reducing the cost, effectively reducing the weight of unmanned aerial vehicle, greatly improving the flexibility and lightness of unmanned aerial vehicle.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of wireless charging, in particular to a double-U-shaped magnetic coupling mechanism for wireless charging of an unmanned aerial vehicle. BACKGROUND

[0002] Wireless charging technology, as a new type of electric energy transmission technology, has attracted extensive attention of scholars in various countries. It is related to electromagnetism, biology, power electronics, electronics and other disciplines and fields, and is known as one of the top ten scientific and technological technologies leading the future of the world. The magnetic coupling mechanism, as an important part of the wireless charging technology, plays an important role in the transmission performance of the whole system. The traditional magnetic coupling mechanism is obtained by combining a circular coil, a square coil and a flat magnetic core, and is suitable for most wireless charging fields, but problems such as poor anti-offset performance, large volume and weight of the receiving end have always existed.

[0003] With the rapid development of unmanned aerial vehicle technology, unmanned aerial vehicles are widely used in scientific research, civil and military fields. Because the flexibility and lightness of the unmanned aerial vehicle need to be ensured, a large-capacity battery cannot be carried, resulting in poor endurance and inability to run for a long time, thereby reducing work efficiency. The traditional contact charging method has the disadvantages of complex operation process, great influence of environmental factors and short service life. The wireless charging technology can realize long-distance charging, and has the advantages of high safety, high flexibility and fast charging speed, and can effectively solve the charging difficulty problem of the unmanned aerial vehicle. SUMMARY

[0004] The technical problem to be solved by the application is to provide a double-U-shaped magnetic coupling mechanism for wireless charging of an unmanned aerial vehicle, which can solve the problems of poor anti-offset performance, large volume and large weight in wireless charging of the unmanned aerial vehicle.

[0005] To solve the above technical problems, the technical solution adopted by the application is: a double-U-shaped magnetic coupling mechanism for wireless charging of an unmanned aerial vehicle, comprising a transmitting end arranged on a wireless charging platform and a receiving end arranged on a body of the unmanned aerial vehicle.

[0006] The transmitting end comprises two U-shaped magnetic cores arranged side by side, and a transmitting end coil is wound on the U-shaped magnetic cores.

[0007] The receiving end comprises a receiving end coil wound on the body of the unmanned aerial vehicle, and the receiving end coil is coupled with the transmitting end coil above the transmitting end.

[0008] Preferably, the transmitting end coil comprises four transmitting end small coils, and the four transmitting end small coils are wound on both ends of the two U-shaped magnetic cores, respectively.

[0009] Preferably, the transmitting end large coil is arranged at the middle part of the two U-shaped magnetic cores in a direction perpendicular to the U-shaped magnetic cores.

[0010] Preferably, the transmitting end coil is a flat solenoid coil.

[0011] Preferably, the U-shaped magnetic core is a ferrite magnetic core.

[0012] Preferably, the receiving end is not provided with a magnetic core, and the receiving end coil is a rectangular hollow solenoid coil.

[0013] The present application provides a double U-shaped magnetic coupling mechanism for wireless charging of a UAV. The receiving end is a rectangular hollow solenoid coil perpendicular to the magnetic core of the transmitting end, so that the receiving end can receive a larger magnetic field area than a planar coil, and more energy can be obtained. In addition, the shape of the receiving end coil is adapted to the UAV body, which can greatly reduce the volume of the UAV. The hollow design of the receiving end reduces the amount of ferrite used, thereby reducing the cost and effectively reducing the weight of the UAV, greatly improving the flexibility and lightness of the UAV. The magnetic field direction of the transmitting end coil is the same and single, which improves the anti-offset performance of the transmitting end and receiving end coils, and effectively reduces the problem of charging efficiency reduction caused by offset due to environmental factors during charging of the UAV. BRIEF DESCRIPTION OF DRAWINGS

[0014] The present application will be further described below in conjunction with the drawings and examples:

[0015] Figure 1 A schematic diagram of the double U-shaped magnetic coupling mechanism for wireless charging of a UAV of the present application;

[0016] Figure 2 A magnetic field distribution diagram of the double U-shaped magnetic coupling mechanism for wireless charging of a UAV of the present application in the x-z plane;

[0017] Figure 3 A variation of the coupling coefficient when the double U-shaped magnetic coupling mechanism for wireless charging of a UAV of the present application is offset in the x, y, and z directions;

[0018] Figure 4 A wireless charging system simulation circuit of the present application;

[0019] Figure 5 A relationship between the output current and the charging equivalent resistance when the double U-shaped magnetic coupling mechanism for wireless charging of a UAV of the present application is offset in the x direction;

[0020] Figure 6 A relationship between the output current and the charging equivalent resistance when the double U-shaped magnetic coupling mechanism for wireless charging of a UAV of the present application is offset in the y direction;

[0021] Figure 7 The relationship between the output current and the charging equivalent resistance when the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application is offset along the z direction;

[0022] Figure 8 The power change when the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application is offset along x, y, and z directions;

[0023] Figure 9 The efficiency change when the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application is offset along x, y, and z directions. DETAILED DESCRIPTION

[0024] As shown in Figure 1 A double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging, comprising a transmitting end arranged on a wireless charging platform and a receiving end arranged on an unmanned aerial vehicle body;

[0025] The transmitting end comprises two U-shaped magnetic cores 3 arranged side by side, and a transmitting end coil is wound on the U-shaped magnetic cores 3.

[0026] The receiving end comprises a receiving end coil 4 wound on the unmanned aerial vehicle body, which is coupled with the transmitting end coil above the transmitting end. The receiving end coil 4 is adapted to the unmanned aerial vehicle body and does not affect the appearance of the unmanned aerial vehicle, but occupies more space in the unmanned aerial vehicle cabin, reducing the volume of the unmanned aerial vehicle and improving its flexibility.

[0027] Preferably, the transmitting end coil comprises four transmitting end small coils 1, and the four transmitting end small coils 1 are wound on the two ends of the two U-shaped magnetic cores 3, respectively.

[0028] Preferably, it further comprises a transmitting end large coil 2, which is wound on the middle part of the two U-shaped magnetic cores 3 in a direction perpendicular to the U-shaped magnetic cores 3.

[0029] Preferably, the transmitting end coil adopts a flat solenoid coil.

[0030] Preferably, the U-shaped magnetic core 3 is a ferrite core.

[0031] Preferably, the receiving end does not have a magnetic core, and the receiving end coil 4 adopts a rectangular hollow solenoid coil.

[0032] Figure 2 The x-z plane magnetic field distribution diagram of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application. The magnetic field direction shown in the figure is single-direction transmission and left-right symmetrical distribution. When the receiving end is offset along the y direction, the magnetic field will be sequentially enhanced from positive to negative direction, indicating that the magnetic field is gathered in the negative direction at this time, slowing down the increase of magnetic resistance.

[0033] Figure 3 For the variation of the coupling coefficient μ of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application when the mechanism is offset along x, y, z, the finite element software is used for analysis, and it can be concluded that when the coupling mechanism is offset by 110 mm, 160 mm, and 30 mm along x, y, and z, the coupling coefficient only decreases by 0.2379, 0.245, and 0.236 of the alignment time, and is greater than 0.1. In order to better illustrate the anti-offset performance of the application, specific case processes will be given below.

[0034] The specific process of this embodiment is as follows: in the wireless charging system, an S-S type compensation network is used to verify the application, and the circuit schematic diagram is given in Figure 4 , and the specific parameters are shown in the following table. In the system, a direct current power with an amplitude of 30 V is used as an output signal, which is converted into a high-frequency alternating current power with a frequency of 85 kHz through a full-bridge inverter circuit, the transmitting end inductance and compensation capacitance are 658.11 μH and 5.33 nF respectively, the receiving end inductance and compensation capacitance are 36.48 μH and 96.20 nF respectively, and the load is 20 Ω.

[0035] Parameter Symbol Parameter Value Uin 30V Lp 658.11 μH Ls 36.48 μH C1 5.33 nF C2 96.20 nF CF 470 μF RB 20 Ω

[0036] Considering that in actual application, the unmanned aerial vehicle will be offset during charging, and the equivalent resistance of the charging battery will increase continuously during the charging process, maintaining the stable current output of the wireless charging system can effectively improve the charging efficiency. Therefore, the relationship between the output current and the charging equivalent resistance of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application when the mechanism is offset along the x direction is given in Figure 5 . It can be seen from Figure 5 that when the charging equivalent resistance changes, the maximum fluctuation of the charging current is not more than 3%. The maximum current fluctuation of the mechanism within the 60 mm offset range along the x direction is not more than 17%. Similarly Figure 6 , the relationship between the output current and the charging equivalent resistance of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application when the mechanism is offset along the y direction is given. It can be seen from Figure 6 that the maximum current fluctuation of the mechanism within the 120 mm offset range along the y direction is not more than 17%. Figure 7 The relationship between the output current and the charging equivalent resistance of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application when the mechanism is offset along the z direction is given, and it can be seen that the maximum current fluctuation of the mechanism within the 20 mm offset range along the z direction is not more than 17%. Figure 8 For the variation of the coupling coefficient μ of the double U-shaped magnetic coupling mechanism for unmanned aerial vehicle wireless charging of the application when the mechanism is offset along x, y, z, the finite element software is used for analysis, and it can be concluded that when the coupling mechanism is offset by 110 mm, 160 mm, and 30 mm along x, y, and z, the coupling coefficient only decreases by 0.2379, 0.245, and 0.236 of the alignment time, and is greater than 0.1. In order to better illustrate the anti-offset performance of the application, specific case processes will be given below. Figure 9The change of the transmission efficiency of the double U-shaped magnetic coupling mechanism for wireless charging of the unmanned aerial vehicle according to the present application when the double U-shaped magnetic coupling mechanism is offset along x, y and z is shown in the table. It can be seen that in the present example, the transmission efficiency of the double U-shaped magnetic coupling mechanism can be within 80% when the double U-shaped magnetic coupling mechanism is offset by 110mm, 160mm and 30mm along x, y and z respectively.

[0037] In summary, the present example provides a double U-shaped magnetic coupling mechanism for wireless charging of the unmanned aerial vehicle. The magnetic coupling mechanism according to the present application has the following advantages compared with the prior art: the receiving coil does not need a magnetic core, which greatly reduces the weight of the unmanned aerial vehicle and ensures the practicability of the unmanned aerial vehicle; the receiving coil is in the shape of a rectangular hollow solenoid coil, which can be directly embedded in the unmanned aerial vehicle body without changing the size and shape of the unmanned aerial vehicle body, greatly reducing the space occupied by the coil in the unmanned aerial vehicle cabin and ensuring the flexibility of the unmanned aerial vehicle. The present application also has good anti-offset performance, can maintain stable charging current output within a certain offset range, and the transmission efficiency can be maintained above 80%.

[0038] The above examples are only preferred technical solutions of the present application, and should not be regarded as a limitation of the present application. The protection scope of the present application should be based on the technical solutions recited in the claims, including equivalent replacement solutions of the technical features recited in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present application.

Claims

1. A double U-shaped magnetic coupling mechanism for wireless charging of a drone, characterized in that: The application relates to a wireless charging system for unmanned aerial vehicles. The transmitting end comprises two U-shaped magnetic cores (3) arranged side by side, and transmitting end coils are arranged on the U-shaped magnetic cores (3); The receiving end comprises receiving end coils (4) arranged on the unmanned aerial vehicle body, and the receiving end coils (4) are coupled with the transmitting end coils above the transmitting end; The transmitting end further comprises a large transmitting end coil (2) arranged at the middle part of the two U-shaped magnetic cores (3) in a direction perpendicular to the U-shaped magnetic cores (3).

2. The dual U-shaped magnetic coupling mechanism for wireless charging of drones of claim 1, wherein: The transmitting end coils comprise four small transmitting end coils (1) arranged at the two ends of the two U-shaped magnetic cores (3) respectively.

3. The dual U-shaped magnetic coupling mechanism for wireless charging of drones of claim 1, wherein: The transmitting end coils adopt flat solenoid-shaped coils.

4. The dual U-shaped magnetic coupling mechanism for wireless charging of drones of claim 1, wherein: The U-shaped magnetic cores (3) are ferrite magnetic cores.

5. The dual U-shaped magnetic coupling mechanism for wireless charging of drones of claim 1, wherein: The receiving end does not have a magnetic core, and the receiving end coils (4) adopt rectangular hollow solenoid-shaped coils.

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