Electric field coupling unmanned aerial vehicle wireless charging system with low electromagnetic interference and control method

Abstract

The invention relates to the field of wireless charging, and discloses an electric field coupling unmanned aerial vehicle wireless charging system with low electromagnetic interference and a control method, and the system comprises a primary side energy transmission unit which comprises a DC power supply, a high-frequency inverter and a primary side compensation sub-circuit which are connected in sequence; the secondary side energy transmission unit comprises an energy storage device, a rectifier and a secondary side compensation sub-circuit which are connected in sequence; the intermediate unit is respectively connected with the primary side compensation sub-circuit and the secondary side compensation sub-circuit and comprises a coupling mechanism and a switch module connected with the coupling mechanism; the transmitting end of the coupling mechanism is based on a four-pole-plate coupling mechanism, transmitting pole plates and dielectric layers are arranged on the inner walls of the four side walls of the unmanned aerial vehicle centering device, and the receiving end of the coupling mechanism still adopts a cylindrical receiving pole plate nested on the outer side of a cylinder at the bottom of an undercarriage; and after the unmanned aerial vehicle is centered, the wireless power supply requirement can be met by controlling the on-off of the corresponding transmitting polar plates no matter the receiving polar plates are longitudinally distributed or transversely distributed.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicle wireless charging, and in particular to a low electromagnetic interference electric field coupling unmanned aerial vehicle wireless charging system and a control method. Background Art

[0002] Drones have been widely used in emergency search and rescue, circuit inspection, and commodity distribution due to their advantages of being light and flexible, safe and reliable, easy to use and maintain, and low cost. However, limited by the battery capacity of drones, the endurance of drones is severely restricted, so the intelligent energy replenishment of drones is an issue that needs to be solved urgently. However, traditional battery replacement and plug-in energy replenishment have some obvious disadvantages. The battery replacement method limits the endurance of drones and reduces work efficiency, while the plug-in energy replenishment method causes serious wear of the interface and poses a safety hazard. Therefore, a safe, efficient, and intelligent energy supply method is an urgent need for drones.

[0003] Wireless power transmission (WPT) technology is a new type of power transmission technology that uses electromagnetic waves or mechanical waves to transmit power from power source to load without electrical contact. Since there is no physical connection between the power source and the load during the transmission process of WPT technology, compared with the traditional contact transmission method, WPT technology can avoid various hidden dangers caused by hardware connection and greatly improve the flexibility of electrical equipment. Among them, electric field coupling-based power transmission (ECPT) technology has the following advantages: 1) The coupling mechanism uses lightweight metal as the transmitting and receiving electrodes, showing advantages such as lightness and good plasticity; 2) ECPT technology uses alternating electric fields to achieve energy transmission, and the system can achieve power transmission across metal barriers; 3) Compared with the magnetic coupling wireless power transmission system, the eddy current loss caused by the ECPT system on the surrounding metal foreign matter can be ignored. Therefore, ECPT technology is more suitable for application in the field of wireless charging of drones.

[0004] At present, there are still few studies on the electric field coupling mechanism suitable for the wireless charging system of unmanned aerial vehicles. The existing literature proposes a coupling mechanism of a pair of disc plates and a pair of annular plates, in which the disc receiving plate is installed on the belly of the drone fuselage, and the annular receiving plate is installed on the landing gear of the drone. Since the electric field coupling mechanism can effectively increase the effective coupling area, it can greatly improve the system transmission power. However, the belly of the drone fuselage is usually used to carry functional equipment such as visible light cameras, and the disc plates in the ECPT system will obviously hinder the installation of these functional equipment. In addition, the annular plates installed on the landing gear of the drone will change the appearance of the drone, which may cause the original fluid mechanics and aerodynamic models of the drone to change, thereby affecting the flight performance.

[0005] In response to the above problems, existing literature proposes a coupling structure in which a parallel rectangular plate is used as the emitter plate and the receiving plate is nested on the outside of the two cylindrical cross bars at the bottom of the landing gear. The coupling structure has a certain installation adaptability and reduces the volume and weight of the receiving end of the coupling mechanism. However, since the emitter plate of the coupling mechanism is larger than the receiving plate, it will result in a larger leakage electric field, which is more likely to cause electromagnetic interference to the drone. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above-mentioned problems existing in the existing wireless charging system for unmanned aerial vehicles, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to provide an electric field coupling UAV wireless charging system with low electromagnetic interference, which aims to solve the problems of large leakage electric field and low adaptability of the existing UAV wireless charging system based on electric field coupling.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: a low electromagnetic interference electric field coupling UAV wireless charging system, the charging system includes a primary energy transmission circuit, a secondary energy transmission circuit and a coupling mechanism; the coupling mechanism transmitting end includes a first emitting electrode plate P respectively arranged on the four side walls of the UAV centering device T1 , the second emitter plate P T2 , the third emitter plate P T3 , the fourth emitter plate P T4 ; The first emitter plate P T1 and the second emitter plate P T2 The third emitter plate P is arranged oppositely. T3 and the fourth emitter plate P T4 The coupling mechanism emitter is connected to the primary energy transmission circuit via a switch module, and the switch module is used to control the first emitter plate P T1 , the second emitter plate P T2 or the third emitter plate P T3 and the fourth emitter plate P T4 Connected to the output end of the primary energy transmission circuit.

[0010] As a preferred solution of the low electromagnetic interference electric field coupling UAV wireless charging system of the present invention, the switch module is used to control the first emitter plate P T1 , the second emitter plate PT2 or the third emitter plate P T3 and the fourth emitter plate P T4 connected to the output end of the primary energy transmission circuit, comprising a first switch S1, a second switch S2, a third switch S3 and a fourth switch S4;

[0011] The first switch S1 and the third switch S3 are respectively connected to the first emitter plate P T1 and the third emitter plate P T3 The other ends of the first switch S1 and the third switch S3 are connected to an output end of the primary energy transmission circuit;

[0012] One end of the second switch S2 and the fourth switch S4 are respectively connected to the second emitter plate P T2 and the fourth emitter P T4 The other ends of the second switch S2 and the fourth switch S4 are connected to another output end of the primary energy transmission circuit.

[0013] As a preferred solution of the low electromagnetic interference electric field coupling UAV wireless charging system of the present invention, wherein: the receiving end of the coupling mechanism includes a first receiving electrode plate P R1 and the second receiving plate P R2 The first receiving plate P R1 and the second receiving plate P R2 The first receiving plate P is respectively installed at both ends of the bottom of the UAV landing gear. R1 and the second receiving plate P R2 They are respectively connected to two input terminals of the secondary side energy transmission circuit.

[0014] As a preferred solution of the low electromagnetic interference electric field coupling UAV wireless charging system of the present invention, wherein: the first receiving plate P R1 and the second receiving plate P R2 It is a cylindrical receiving plate respectively embedded in the outer side of the cylinders at both ends of the bottom of the landing gear.

[0015] As a preferred solution of the low electromagnetic interference electric field coupling UAV wireless charging system of the present invention, the primary energy transmission circuit includes a DC power supply E connected in sequence. dc , a high-frequency inverter and a primary compensation sub-circuit; the output end of the primary compensation sub-circuit is the output end of the primary energy transmission circuit.

[0016] As a preferred solution of the low electromagnetic interference electric field coupled UAV wireless charging system described in the present invention, the secondary energy transmission circuit includes a secondary compensation subcircuit and a rectifier connected in sequence; the input end of the secondary compensation subcircuit is the input end of the secondary energy transmission circuit, and the output end of the rectifier is connected to the load RL of the UAV through a DC-DC converter.

[0017] As a preferred solution of the low electromagnetic interference electric field coupling drone wireless charging system described in the present invention, the primary side compensation subcircuit and the secondary side compensation subcircuit adopt a symmetrically arranged LC network topology structure.

[0018] As a preferred solution of the low electromagnetic interference electric field coupling unmanned aerial vehicle wireless charging system of the present invention, wherein: the first emitter plate P T1 , the second emitter plate P T2 , the third emitter plate P T3 and the fourth emitter plate P T4 A dielectric plate is installed on the end surface on one side away from the side wall of the UAV centering device.

[0019] As a preferred solution of the low electromagnetic interference electric field coupling drone wireless charging system described in the present invention, it also includes a system controller, and the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4 are all controlled to be turned on or off by the system controller.

[0020] The object of the present invention is to provide a control method for a low electromagnetic interference electric field coupling UAV wireless charging system, which is used to control the above-mentioned low electromagnetic interference electric field coupling UAV wireless charging system, and the specific steps are:

[0021] S1: After landing, the drone communicates with the drone nest and completes the centering through the centering device. At the initial moment, the system controller controls the first switch S1 and the second switch S2 to be turned on and the first switch S3 and the second switch S4 to be turned off by default;

[0022] S2: Perform a low-power test on the system, collect the input voltage and current and the output voltage and current of the system, and determine whether the drone rotates 90° after returning to the center. If not, go to step S4; if so, go to step S3;

[0023] S3: the system controller controls the first switch S1 and the second switch S2 to be disconnected and the first switch S3 and the second switch S4 to be turned on;

[0024] S4: Start charging, collect the output voltage and current, and determine whether the output voltage and current meet the charging requirements. If so, continue charging; if not, control the DC-DC converter until the charging requirements are met.

[0025] S5: Determine whether the power of the drone load RL is fully charged. If it is fully charged, the charging is terminated. If it is not fully charged, the charging is continued until it is fully charged.

[0026] Beneficial effects of the present invention:

[0027] 1. The transmitting end of the coupling mechanism of the present application is based on the quadrupole coupling mechanism, and the transmitting plate and the dielectric layer are placed on the inner walls of the four side walls of the UAV centering device. The receiving end of the coupling mechanism still uses a cylindrical receiving plate nested on the outside of the bottom cylinder of the landing gear, and the main working coupling area of ​​the coupling mechanism is optimized from the vertical direction to the horizontal direction, which effectively reduces the longitudinal leakage field distribution and thus reduces the electromagnetic interference to the UAV. After the UAV is centered, whether the receiving plate is distributed longitudinally or horizontally, the wireless power supply requirement can be achieved by controlling the corresponding transmitting plate on and off.

[0028] 2. The first receiving plate and the second receiving plate of the present application are both formed by copper foil or aluminum foil wound around the landing gear of the UAV, which can achieve lightweight without changing the original appearance of the UAV and have a small size, thereby reducing the impact of the receiving plate on the original aerodynamic model of the UAV. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0030] Figure 1 It is a schematic diagram of the structure of the electric field coupling UAV wireless charging system of the present invention.

[0031] Figure 2 It is a schematic diagram of the structure of the coupling mechanism when the receiving plates of the present invention are distributed laterally.

[0032] Figure 3 It is a schematic diagram of the structure of the coupling mechanism when the receiving plates of the present invention are distributed longitudinally.

[0033] Figure 4 This is an equivalent circuit diagram of the electric field coupled UAV wireless charging system of the present invention.

[0034] Figure 5 The present invention is a flow chart of the control method of the electric field coupling UAV wireless charging system.

[0035] Figure 6 This is a waveform diagram of the voltage between the plates during simulation of the system of the present invention.

[0036] Figure 7This is a strong coupling field distribution diagram of the coupling mechanism of the system of the present invention.

[0037] Figure 8 This is a vertical leakage electric field distribution diagram of the coupling mechanism of the system of the present invention.

[0038] Fig. 9 This is the horizontal leakage electric field distribution diagram of the coupling mechanism of the system of the present invention.

[0039] Fig.10 This is a horizontal leakage electric field distribution diagram of the traditional coupling mechanism in the comparative simulation of the present invention.

[0040] Fig.11 The vertical leakage electric field distribution diagram of the traditional coupling mechanism in the comparative simulation of the present invention. DETAILED DESCRIPTION

[0041] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0043] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0044] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0045] Example 1

[0046] Reference Figure 1 , which is the first embodiment of the present invention, provides a low electromagnetic interference electric field coupling UAV wireless charging system, the UAV wireless charging system includes a primary energy transmission circuit, a secondary energy transmission circuit and a coupling mechanism, the coupling mechanism transmitting end includes a first emitting electrode plate P respectively arranged on the four side walls of the UAV centering device T1 , the second emitter plate P T2 , the third emitter plate PT3 , the fourth emitter plate P T4 .

[0047] The first emitter plate P T1 and the second emitter plate P T2 The third emitter plate P is arranged oppositely. T3 and the fourth emitter plate P T4 The coupling mechanism emitter is connected to the primary energy transmission circuit via a switch module, which is used to control the first emitter plate P T1 , the second emitter plate P T2 or the third emitter plate P T3 and the fourth emitter plate P T4 Connected to the output end of the primary energy transmission circuit.

[0048] In this embodiment, the first emitter plate P T1 and the second emitter plate P T2 The third emitter plate P T3 and the fourth emitter plate P T4 Disconnect, or the third emitter plate P T3 and the fourth emitter plate P T4 The first emitter plate P T1 and the second emitter plate P T2 Disconnected, the coupling capacitance of the two receiving plate distribution conditions is basically the same. In order to increase the coupling capacitance of the coupling mechanism to achieve high-power and efficient power transmission, the first emitter plate P T1 , the second emitter plate P T2 , the third emitter plate P T3 and the fourth emitter plate P T4 A dielectric plate P is installed on the end surface of the side away from the side wall of the UAV return device. d In this embodiment, the dielectric plate P d Choose tempered glass.

[0049] As an embodiment of the present invention, Figure 1 As shown, the switch module includes a first switch S1, a second switch S2, a third switch S3 and a fourth switch S4;

[0050] The first switch S1 and the third switch S3 are respectively connected to the first emitter plate P T1 and the third emitter plate P T3 The other ends of the first switch S1 and the third switch S3 are connected to an output end of the primary energy transmission circuit;

[0051] One end of the second switch S2 and the fourth switch S4 are respectively connected to the second emitter plate P T2 and the fourth emitter P T4The other ends of the second switch S2 and the fourth switch S4 are connected to another output end of the primary energy transmission circuit.

[0052] In this embodiment, since the UAV system has a weak anti-electromagnetic interference capability, it is necessary to focus on the leakage electric field distribution of the electric field coupling mechanism. The electric field coupling mechanism emitter plate and dielectric proposed in this application are located on both sides of the UAV landing gear after centering instead of under the UAV landing gear, so its main working coupling surface is the horizontal direction of the landing gear instead of the vertical direction of the landing gear, which can greatly reduce the leakage electric field distribution in the vertical direction, and minimize the electromagnetic interference to the UAV fuselage while still ensuring the coupling capacitance that meets the system power transmission and efficiency index requirements. At the same time, although the current application of UAV centering devices is relatively mature, for the application of electric field coupling UAV wireless charging, the 90° rotation offset that may occur after the UAV is centered will have a great impact on the coupling capacitance of the traditional electric field coupling mechanism, and the electric field coupling UAV wireless charging system proposed in this invention controls the excitation switch of the four emitter plates, so that regardless of whether the UAV is rotated 90° after centering, it can ensure a higher coupling capacitance to achieve efficient power transmission that meets the requirements.

[0053] As an embodiment of the present invention, Figure 1 As shown, the receiving end of the coupling mechanism includes a first receiving plate P R1 and the second receiving plate P R2 ;

[0054] The first receiving plate P R1 and the second receiving plate P R2 Installed at both ends of the bottom of the UAV landing gear, the first receiving plate P R1 and the second receiving plate P R2 The first receiving plate P is connected to the two input terminals of the secondary energy transmission circuit respectively. R1 and the second receiving plate P R2 It is a cylindrical receiving plate respectively embedded in the outer side of the cylinders at both ends of the bottom of the landing gear.

[0055] In this embodiment, the first receiving plate P R1 and the second receiving plate P R2 They are all made of copper foil or aluminum foil wrapped around the drone landing gear, which can achieve lightweight without changing the original appearance of the drone.

[0056] As an embodiment of the present invention, Figure 1 and Figure 4 As shown, the primary energy transmission circuit includes a DC power supply E connected in sequence dc , high frequency inverter and primary side compensation sub-circuit;

[0057] The output end of the primary side compensation sub-circuit is the output end of the primary side energy transmission circuit.

[0058] In this embodiment, the DC power supply E dc The provided DC input voltage is converted into high-frequency AC power through a high-frequency inverter to supply the subsequent circuit. The primary side compensation subcircuit realizes functions such as filtering, reactive power compensation, and pumping voltage to obtain a high-frequency excitation voltage.

[0059] As an embodiment of the present invention, Figure 1 and Figure 4 As shown, the secondary side energy transmission circuit includes a secondary side compensation subcircuit and a rectifier connected in sequence;

[0060] The input end of the secondary side compensation subcircuit is the input end of the secondary side energy transmission circuit, and the output end of the rectifier is connected to the load R of the drone through a DC-DC converter. L connect.

[0061] In this embodiment, the two pairs of corresponding plates generate "displacement current" under high-frequency and high-voltage excitation, thereby realizing the transmission of electric energy. The secondary compensation subcircuit realizes impedance matching, and the rectifier converts the obtained high-frequency AC power into DC power. Considering the mismatch between the converted DC voltage and current and the drone battery, a DC-DC converter is connected after the rectifier output to meet the drone battery charging requirements. In this embodiment, the load R L Provide power supply for drones.

[0062] As an embodiment of the present invention, Figure 1 and Figure 4 As shown, the primary side compensation sub-circuit and the secondary side compensation sub-circuit adopt a symmetrically arranged LC network topology structure.

[0063] In this embodiment, the high-frequency inverter is a voltage-type full-bridge inverter, which is composed of four power MOSFETs S1 to S4, and the rectifier is composed of four Schottky diodes D1 to D4 and a filter capacitor C f The primary compensation subcircuit includes the primary compensation capacitor C ex1 and the primary compensation inductor L1, the secondary compensation subcircuit includes the secondary compensation capacitor C ex2 And the secondary side compensation inductor L2.

[0064] As an embodiment of the present invention, Figure 1 As shown, a system controller is also included, and the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4 are all controlled to be turned on or off by the system controller.

[0065] In this embodiment, the system controller controls the first switch S1 and the second switch S2 to be turned on and the first switch S3 and the second switch S4 to be turned off by default, so that the emitter plate P T1 and P T2 Provide high-frequency excitation voltage. The system controller feeds back the rectifier output voltage and current to the system controller through the communication module, and compares the inverter output voltage and current feedback to determine the distribution of the drone receiving plates (determine whether the drone rotates 90° after returning to the center), and controls the corresponding switch to open (if an offset occurs, the system controller controls the first switch S1 and the second switch S2 to open and the first switch S3 and the second switch S4 to turn on).

[0066] Example 2

[0067] Reference Figure 1 , which is the second embodiment of the present invention. This embodiment is different from the first embodiment in that it provides a control method for an electric field coupling UAV wireless charging system with low electromagnetic interference, such as Figure 5 As shown in , it is used to control the low electromagnetic interference electric field coupling drone wireless charging system of Example 1, and the specific steps are:

[0068] S1: After landing, the drone communicates with the drone nest and completes the centering through the centering device. At the initial moment, the system controller controls the first switch S1 and the second switch S2 to be turned on and the first switch S3 and the second switch S4 to be turned off by default;

[0069] S2: Perform a low-power test on the system, collect the input voltage and current and the output voltage and current of the system, and determine whether the drone rotates 90° after returning to the center. If not, go to step S4; if so, go to step S3;

[0070] S3: the system controller controls the first switch S1 and the second switch S2 to be disconnected and the first switch S3 and the second switch S4 to be turned on;

[0071] S4: Start charging, collect the output voltage and current, and determine whether the output voltage and current meet the charging requirements. If so, continue charging; if not, control the DC-DC converter until the charging requirements are met.

[0072] S5: Determine the drone load R L Check whether the battery is fully charged. If it is fully charged, stop charging. If not, continue charging until it is fully charged.

[0073] S6: System Simulation:

[0074] S6.1 Performance simulation: In order to verify that the new coupling mechanism can reduce the leakage field area and thus reduce the electromagnetic interference to the drone, a simulation model based on the Maxwell finite element simulation platform is built. Figure 2The coupling mechanism model shown in Figure 1 is shown in Figure 1. Since the excitation voltages of the emitter plate and the receiving plate in the static field simulation are fixed, it is necessary to build the following on the Matlab / Simulink simulation platform: Figure 4 The circuit model of the entire wireless charging system is simulated to obtain the voltage between the plates at a certain moment. The system can achieve 144W power transmission, and the system parameters are shown in Table 1.

[0075] Table 1 System parameters

[0076]

[0077] The voltage waveform between each board is as follows Figure 6 As shown. When the emitter plate P T1 or P T3 With receiving plate P R1 When the voltage between the boards is the maximum, the instantaneous values ​​of the voltage between the boards are shown in Table 2.

[0078] Table 2 Instantaneous voltage value between each plate

[0079]

[0080] Assume that the second emitter plate P T2 or the fourth emitter plate P T4 If the excitation voltage is 0V, set P according to the data in Table 2. T1 or P T3 , P R1 and P R2 The excitation voltage is , and the strong coupling field distribution and leakage field distribution of the coupling mechanism are obtained by simulation, as shown in Figure 7 , Figure 8 and Fig. 9 As shown. Figure 7 It can be found that the emitter plate and the receiver plate can form an effective coupling, and the strong coupling area is concentrated between the receiver plate and the emitter plate. Figure 8 and Fig. 9 It can be seen that the main working coupling area of ​​the coupling mechanism is the horizontal direction rather than the vertical direction. Therefore, the leakage field distribution of the coupling mechanism in the vertical direction is small, and the leakage field strength at 90mm above the coupling mechanism is less than 333V / m, which causes very limited electromagnetic interference to the drone. The coupling mechanism also has a small leakage field distribution in the horizontal direction. The leakage field strength at 80mm outside the coupling mechanism is less than 333V / m, which is lower than the leakage field strength of 412V / m at 2MHz, and is in a safe area.

[0081] S6.2 Comparative simulation: A traditional coupling mechanism is built, and the transmitting plate is located vertically below the receiving plate. According to the Maxwell finite element simulation platform and the cross-coupling capacitance calculation formula, the coupling capacitance and coupling coefficient of the two types of coupling mechanisms are obtained, as shown in Table 3. It can be seen that the coupling mechanism proposed in the present invention can achieve basically the same coupling mutual capacitance as the traditional one while effectively reducing the volume of the transmitting end, and its coupling coefficient is higher than the traditional one due to the less cross-coupling capacitance of the plates.

[0082] Table 3 Coupling capacitance and coupling coefficient of two types of coupling mechanisms

[0083]

[0084] When both coupling mechanisms are under the same voltage excitation, the leakage field distribution of the traditional coupling mechanism is as follows: Fig.10 and Fig.11 As shown, it can be seen that the main working coupling surface of the traditional coupling mechanism is distributed longitudinally, and there is still an area with an electric field strength higher than 1333V / m 400mm above the receiving plate. The new coupling mechanism proposed in this scheme can achieve an electric field strength lower than 333V / m at 90mm above the receiving plate. The new coupling mechanism proposed in this application has a smaller leakage field area, and the electromagnetic interference caused to the drone is significantly reduced. In addition, the leakage field distribution of the new coupling mechanism proposed in this scheme on the horizontal plane is also better than that of the traditional coupling mechanism, thanks to its design of a smaller transmitting plate that matches the receiving plate.

[0085] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. Low electromagnetic interference electric field coupling drone wireless charging system, characterized by: include, A primary side energy transmission circuit, a secondary side energy transmission circuit and a coupling mechanism; The coupling mechanism transmitting end comprises first transmitting plates P respectively arranged on four side walls of the UAV centering device T1 , the second emitter plate P T2 , the third emitter plate P T3 , the fourth emitter plate P T4 ; The first emitter plate P T1 and the second emitter plate P T2 The third emitter plate P is arranged oppositely. T3 and the fourth emitter plate P T4 The coupling mechanism emitter is connected to the primary energy transmission circuit via a switch module, and the switch module is used to control the first emitter plate P T1 , the second emitter plate P T2 or the third emitter plate P T3 and the fourth emitter plate P T4 Connected to the output end of the primary energy transmission circuit.

2. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 1 is characterized by: The switch module is used to control the first emitter plate P T1 , the second emitter plate P T2 or the third emitter plate P T3 and the fourth emitter plate P T4 connected to the output end of the primary energy transmission circuit, comprising a first switch S1, a second switch S2, a third switch S3 and a fourth switch S4; The first switch S1 and the third switch S3 are respectively connected to the first emitter plate P T1 and the third emitter plate P T3 The other ends of the first switch S1 and the third switch S3 are connected to an output end of the primary energy transmission circuit; One end of the second switch S2 and the fourth switch S4 are respectively connected to the second emitter plate P T2 and the fourth emitter P T4 The other ends of the second switch S2 and the fourth switch S4 are connected to another output end of the primary energy transmission circuit.

3. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 2 is characterized by: The coupling mechanism receiving end includes a first receiving plate P R1 and the second receiving plate P R2 ; The first receiving plate P R1 and the second receiving plate P R2 The first receiving plate P is respectively installed at both ends of the bottom of the UAV landing gear. R1 and the second receiving plate P R2 They are respectively connected to two input terminals of the secondary side energy transmission circuit.

4. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 3 is characterized by: The first receiving plate P R1 and the second receiving plate P R2 It is a cylindrical receiving plate respectively embedded in the outer side of the cylinders at both ends of the bottom of the landing gear.

5. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 4 is characterized in that: The primary energy transmission circuit comprises a DC power supply, a high frequency inverter and a primary compensation subcircuit which are connected in sequence; The output end of the primary compensation sub-circuit is the output end of the primary energy transmission circuit.

6. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 5, characterized in that: The secondary side energy transmission circuit comprises a secondary side compensation subcircuit and a rectifier connected in sequence; The input end of the secondary side compensation subcircuit is the input end of the secondary side energy transmission circuit, and the output end of the rectifier is connected to the load of the drone through a DC-DC converter.

7. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 6, characterized in that: The primary side compensation subcircuit and the secondary side compensation subcircuit adopt a symmetrically arranged LC network topology structure.

8. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 7, characterized in that: The first emitter plate P T1 , the second emitter plate P T2 , the third emitter plate P T3 and the fourth emitter plate P T4 A dielectric plate is installed on the end surface on one side away from the side wall of the UAV centering device.

9. The low electromagnetic interference electric field coupling UAV wireless charging system according to claim 8, characterized in that: Also includes, The system controller, the first switch S1, the second switch S2, the third switch S3 and the fourth switch S4 are all controlled to be turned on or off by the system controller.

10. A control method for an electric field coupled drone wireless charging system with low electromagnetic interference, characterized in that: Used to control the low electromagnetic interference electric field coupling drone wireless charging system according to any one of claims 1 to 9, the specific steps are: S1: After landing, the drone communicates with the drone nest and completes the centering through the centering device. At the initial moment, the system controller controls the first switch S1 and the second switch S2 to be turned on and the first switch S3 and the second switch S4 to be turned off by default; S2: Perform a low-power test on the system, collect the input voltage and current and the output voltage and current of the system, and determine whether the drone rotates 90° after returning to the center. If not, go to step S4; if so, go to step S3; S3: the system controller controls the first switch S1 and the second switch S2 to be disconnected and the first switch S3 and the second switch S4 to be turned on; S4: Start charging, collect the output voltage and current, and determine whether the output voltage and current meet the charging requirements. If so, continue charging; if not, control the DC-DC converter until the charging requirements are met. S5: Determine whether the power of the drone load RL is fully charged. If it is fully charged, the charging is terminated. If it is not fully charged, the charging is continued until it is fully charged.

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