Charging power maximization control system and method for three-dimensional three-layer unmanned aerial vehicle wireless charging library

Abstract

The invention discloses a charging power maximization control system and method for a three-dimensional three-layer unmanned aerial vehicle wireless charging library, and the system comprises a three-layer unmanned aerial vehicle wireless charging platform. The resonance is configured according to the sizes and the frequencies of the transmitting coil and the receiving coil, and the compensation capacitance is determined; monitoring whether the charging platforms have loads or not, and determining five charging scenes according to the number of the loads on the three layers of charging platforms; in each charging scene, the charging electric quantity of each unmanned aerial vehicle is monitored, and according to the charging electric quantity and the compensation capacitance, the topology and frequency of the transmitting coil and the connection mode of the coil are determined, so that the charging power of the unmanned aerial vehicle of the whole system is maximized. According to the invention, a basic task of power maximization is realized for an unmanned aerial vehicle charging library application scene, the output power and application flexibility of the system are improved, the service life of charging equipment is prolonged, and the charging efficiency and stability are remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless charging, and in particular relates to a three-dimensional three-layer unmanned aerial vehicle wireless charging depot charging power maximization control system and method. Background Art

[0002] In recent years, drone inspection has become the most widely used inspection method for power grids. However, drones have the problem of high power consumption. Traditional wired charging methods can only guarantee one-time power supply, which makes it impossible for drones to work for a long time and perform inspection tasks efficiently, and the overall operation efficiency cannot be guaranteed. Since wireless power transmission technology is contactless power supply, inspection drones can be wirelessly charged by simply equipping wireless power transmitting and receiving devices. Wireless charging technology has many advantages in inspection drones, so it has received widespread attention. The structure of the magnetically coupled wireless power transmission system mainly includes an alternating power supply, a resonant topology circuit, a transmitting coil and a receiving coil, a rectifier, a filter and a load. Wireless power transmission is very challenging in terms of transmission distance. The coupling strength between the transmitting and receiving coils decreases rapidly with the increase of the transmission distance, so that the wireless power transmission efficiency will drop significantly with the increase of the transmission distance. In the existing research context, it is usually considered to increase the relay coil to enhance the coupling and expand the transmission distance of the wireless power transmission system. However, in the application scenario of the drone charging depot, there is no suitable installation position for the relay coil, which affects the charging power of the drone. Summary of the invention

[0003] Purpose of the invention: The purpose of the present invention is to provide a three-dimensional three-layer UAV wireless charging station charging power maximization control system and method to solve the problem of insufficient power caused by excessive transmission distance.

[0004] Technical solution: The three-dimensional three-layer UAV wireless charging depot charging power maximization control system described in the present invention includes: a power circuit and a control circuit. The power circuit includes a full-bridge inverter and a UAV wireless charging depot. The UAV wireless charging depot includes a three-layer charging platform. Each charging platform includes a transmitter located on the charging platform, a receiver located on the UAV, a rectifier circuit and a filter circuit. The full-bridge inverter outputs three high-frequency alternating currents to the transmitter of the three-layer charging platform respectively. The transmitter and the receiver are connected by magnetic coupling. The output signal of the receiver charges the UAV after passing through the rectifier circuit and the filter circuit in sequence; the control circuit includes an inverter dual-frequency output circuit and a monitoring circuit. The inverter dual-frequency output circuit is used to output high-frequency or low-frequency alternating current. The monitoring circuit includes three charging platform monitoring circuits. The three charging platform monitoring circuits are respectively used to monitor the power and quantity of the UAVs on the three-layer charging platform; the charging frequency, topology and coil connection method of each transmitter are determined according to the monitored power and the number of UAVs to maximize the UAV charging power of the entire system.

[0005] Optionally, the frequency of the low-frequency AC power output by the inverter dual-frequency output circuit is the basic charging frequency f1 of the transmitter, and the high-frequency AC power is the auxiliary charging frequency f2. The basic charging frequency f1 is used when the transmitter transmits energy to the receiving end on the current charging platform, and the auxiliary charging frequency f2 is used when the transmitter transmits energy to the receiving end of the adjacent charging platform.

[0006] Optionally, the transmitting end includes a transmitting coil and a resonant network thereof, and the receiving end includes a receiving coil and a resonant network thereof, The receiving coil topology circuit adopts S topology; When the drone's power is less than SOC1, both the transmitting coil and the receiving coil use the S topology, and the system uses the SS topology for charging; When the drone's power level is greater than SOC1, the transmitting coil switches from the S topology to the LCC topology, and the system uses the LCC-S topology for charging.

[0007] Optionally, the coil connection between each transmitting end is: When all three drones are charging in the charging station, the coils of the three transmitters are connected in parallel; When the drones on the third-layer charging platform are fully charged and fly away from the charging station, the drones on the first-layer charging platform and the second-layer charging platform continue to charge; the transmitting coil of the third-layer charging platform charges the drones on the second-layer charging platform, and the first-layer transmitting coil is connected in parallel with the second-layer transmitting coil and then connected in series with the third-layer transmitting coil; When the drones on the second-level charging platform are fully charged and fly away from the charging station, the drones on the first-level and third-level charging platforms continue to charge; the transmitting coil of the second-level charging platform charges the drones on the first-level and third-level charging platforms, and the first-level transmitting coil is connected in parallel with the third-level transmitting coil and then connected in series with the second-level transmitting coil; When the drones on the second and third charging platforms are fully charged and fly away from the charging station, the drones on the first charging platform continue to charge; the second transmitting coil charges the drones on the first charging platform, and the second transmitting coil is connected in parallel with the third transmitting coil and then in series with the first transmitting coil; When the drones on the first and third charging platforms are fully charged and fly away from the charging station, the drones on the second charging platform continue to charge; the first and second transmitting coils both charge the drones on the second charging platform, and the first transmitting coil is connected in parallel with the third transmitting coil and then in series with the second transmitting coil.

[0008] Optionally, both the transmitting coil and the receiving coil adopt a planar spiral coil structure. The control method of the three-dimensional three-layer wireless charging bank for unmanned aerial vehicles according to the present invention for maximizing the charging power of the control system comprises the following steps: Build a three-dimensional three-layer drone wireless charging depot to maximize charging power control system; Configure resonance according to the size and frequency of the transmitting coil and the receiving coil, and determine the size of the compensation capacitor; Monitor whether there is load on the charging platform, and determine five charging scenarios based on the number of loads on the three-layer charging platform; in each charging scenario, monitor the charging power of each drone. When the power of the drone is less than SOC1, the transmitting coil and the receiving coil both adopt the S topology, and the system adopts the SS topology for charging; when the power of the drone is greater than SOC1, the transmitting coil switches from the S topology to the LCC topology, and the system adopts the LCC-S topology for charging; when the drone completes charging and leaves the charging platform, the operating frequency of the transmitting coil on this layer of the charging platform switches to high frequency, and the topology switches to the S topology, so that it can charge the drones on the adjacent charging platform and ultimately maximize the drone charging power of the entire system.

[0009] Furthermore, the resonance is configured according to the size and frequency of the transmitting coil and the receiving coil, and the size of the compensation capacitor is determined; specifically: When the system topology is SS topology, the compensation capacitor of the transmitting coil for: , Compensation capacitor for receiving coil for: , When the system topology is LCC-S, the compensation capacitor of the transmitting coil for: , Compensation capacitor for receiving coil for: , in, is the self-inductance of the transmitting coil, is the self-inductance of the receiving coil, is the angular frequency, To compensate for the inductance.

[0010] Furthermore, the five charging scenarios are as follows: The first charging scenario: All three drones are charged in the warehouse. In this case, the three drones are charged normally. When the power of the drone reaches SOC1, the power monitoring circuit sends a signal, and the system topology switches from SS topology to LCC-S topology, and then the three transmitting coils are connected in parallel. The second charging scenario: the drone on the third-layer charging platform is fully charged and flies away from the charging depot, while the drones on the first-layer charging platform and the second-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and the topology of the third-layer transmitting coil is switched from the LCC topology to the S topology to charge the drone on the second-layer charging platform. The first-layer transmitting coil is connected in parallel with the second-layer transmitting coil and then in series with the third-layer transmitting coil; The third charging scenario: the drones on the second-layer charging platform are fully charged and fly away from the charging depot, while the drones on the first-layer and third-layer charging platforms continue to charge; the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switches from the LCC topology to the S topology to charge the drones on the first-layer and third-layer charging platforms. The first-layer transmitting coil is connected in parallel with the third-layer transmitting coil and then connected in series with the second-layer transmitting coil; The fourth charging scenario: the drones on the second-layer charging platform and the third-layer charging platform are fully charged and fly away from the charging depot, while the drones on the first-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The second-layer transmitting coil charges the drones on the first-layer charging platform, and the second-layer transmitting coil and the third-layer transmitting coil are connected in parallel and then in series with the first-layer transmitting coil; The fifth charging scenario: the drones on the first-layer charging platform and the third-layer charging platform complete charging and fly away from the charging depot, while the drones on the second-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the first-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The first-layer and second-layer transmitting coils both charge the drones on the second-layer charging platform. The first-layer transmitting coil and the third-layer transmitting coil are connected in parallel and then in series with the second-layer transmitting coil.

[0011] Furthermore, the transmission power between the transmitting coil and the receiving coil when the frequency is the auxiliary charging frequency f2 is obtained by setting different high frequency values ​​according to the specific requirements of the user; specifically: make ,in, is the transmission power between the transmitting coil and the receiving coil when the transmitting coil frequency is the basic charging frequency f1, is the transmission power between the transmitting coil and the receiving coil when the frequency is the auxiliary charging frequency f2; When the transmitting coil of the adjacent charging platform participates in the power transmission, before the drone reaches SOC1: , in, is the angular frequency at the basic charging frequency f1, is the angular frequency of the auxiliary charging frequency f2, is the mutual inductance between the transmitting coil and the receiving coil, To compensate for the internal resistance of the coil, is the internal resistance of the transmitting coil, is the internal resistance of the receiving coil, is the load resistance; When the drone battery reaches SOC1: , in, To compensate for the inductance, is the compensation capacitance of the transmitting coil.

[0012] The present invention also provides an electronic device, comprising a memory and a processor, wherein: A memory for storing computer programs that can be run on the processor; A processor is used to execute the steps of the control method when running the computer program.

[0013] Beneficial effects: Compared with the prior art, the significant technical effects of the present invention are as follows: through the design of a three-dimensional three-layer UAV wireless charging warehouse, combined with the design of a power circuit and a control circuit, the charging power is maximized; a magnetically coupled resonant wireless power transmission circuit is adopted, and the switching of the basic frequency f1 and the auxiliary frequency f2 is realized through the inverter dual-frequency output circuit, ensuring efficient charging of the UAV in different charging scenarios; the monitoring circuit dynamically adjusts the charging topology (switching between SS topology and LCC-S topology) and the operating frequency of the transmitting coil through power monitoring and load monitoring, ensuring the stability and efficiency of the charging process; in addition, through the flexible switching of the parallel and series connection modes of the transmitting coil in different charging scenarios, the charging power of the system is further improved; the combination of these technical features not only solves the problem of insufficient power caused by excessive transmission distance, but also significantly improves the stability of the system and the life of the charging equipment, meeting the needs of long-term inspection of UAVs. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the control system circuit principle of the present invention; Figure 2 is a flow chart of the control method of the present invention; Figure 3 This is the block diagram of the power circuit structure of the wireless charging bank for drones; Figure 4 Schematic diagrams of five charging scenarios of the wireless charging library for drones, where (a) is a schematic diagram of the first charging scenario, (b) is a schematic diagram of the second charging scenario, (c) is a schematic diagram of the third charging scenario, (d) is a schematic diagram of the fourth charging scenario, and (e) is a schematic diagram of the fifth charging scenario; Figure 5 It is a schematic diagram of the transmitting coil topology circuit; Figure 6 This is a schematic diagram of the load monitoring control circuit. DETAILED DESCRIPTION

[0015] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be understood as limiting the present invention.

[0016] like Figure 1 As shown, the three-dimensional three-layer UAV wireless charging depot charging power maximization control system of the present invention includes a DC power supply Vin, a power circuit, a control circuit and a load. The DC power supply is used to provide power for the entire system, and the load is a UAV.

[0017] The power circuit includes a full-bridge inverter and a three-layer wireless charging library for unmanned aerial vehicles. The three-layer wireless charging library for unmanned aerial vehicles includes a first charging platform, a second charging platform and a third charging platform. Each charging platform includes a magnetic coupling resonant wireless power transmission circuit, a rectifier circuit and a filter circuit connected in sequence. The magnetic coupling resonant wireless power transmission circuit includes a transmitter arranged on the charging platform and a receiver arranged on the unmanned aerial vehicle. The transmitter includes a transmitter coil and a resonant network thereof, and the receiver includes a receiver coil and a resonant network thereof. The DC power source is converted by a full-bridge inverter to output high-frequency alternating current, which is respectively connected to the input ends of the three charging platforms, that is, the high-frequency alternating current converted and output by the full-bridge inverter is input to the input end of the magnetic coupling resonant wireless power transmission circuit. The output of the magnetic coupling resonant wireless power transmission circuit is sequentially connected to the rectifier circuit and the filter circuit to convert the alternating current into direct current. However, the rectified direct current is not completely smooth, but has a large pulsation component. The filter circuit can smooth these pulsations through the charging and discharging characteristics of the capacitor, and output a more stable direct current, so as to ensure that the unmanned aerial vehicle can obtain a stable power supply.

[0018] The control circuit includes an inverter dual-frequency output circuit and a monitoring circuit. The purpose of the inverter dual-frequency output circuit is to output high-frequency and low-frequency alternating current. The hardware design of the multi-level inverter is used in conjunction with the control strategy of the multi-level modulation technology to realize that one inverter generates two outputs of different frequencies at the same time, and the output waveform has high quality and low harmonic content; the monitoring circuit includes a first charging platform monitoring circuit, a second charging platform monitoring circuit and a third charging platform monitoring circuit. The first charging platform monitoring circuit, the second charging platform monitoring circuit and the third charging platform monitoring circuit are used to monitor the first charging platform, the second charging platform and the third charging platform respectively; each charging platform monitoring circuit includes a drone power monitoring circuit and a drone number monitoring circuit. The drone power monitoring circuit is used to monitor the power of the drone on the charging platform when charging. When the power of the drone is less than SOC1, a switch on-off signal is sent, and the transmitting coil and the receiving coil of this layer both adopt the S topology, and the entire system adopts the SS topology for charging; when the power of the drone is greater than SOC1, a switch on-off signal is sent, and the transmitting coil of this layer is switched from the S topology to the LCC topology, and the entire system topology is switched to the LCC-S for charging. The drone quantity monitoring circuit is used to monitor whether there are drones on the charging platform. When the drone is fully charged and flies away, a signal is sent, and the operating frequency of the transmitting coil on the charging platform is switched from f1 to f2, increasing the transmission distance of the transmitting coil on this layer, so that energy can be transmitted to the drones on the adjacent charging platform, that is, charging the drones on the adjacent charging platform. Since the SS topology transmission power is greater than the LCC-S topology transmission power, the LCC topology of the transmitting coil is switched to the S topology at the same time to increase the charging power. Based on the determination of the system topology and frequency, the series-parallel connection method between the transmitting coils is designed to maximize the system charging power. Depending on the charging scenario, the control strategy also changes accordingly.

[0019] The full-bridge inverter uses four MOS tubes (S1, S2, S3 and S4) as shown in Figure 1 The three-way AC power output is respectively input into the magnetic coupling resonant wireless power transmission circuit of the first charging platform, the second charging platform and the third charging platform.

[0020] The receiving coil topology will adopt the S topology. The drone will be charged with the SS topology in the early stage of charging. It can provide an output characteristic of approximately constant current near the resonant frequency, which is in line with the initial stage of battery charging (constant current charging stage), and can provide a stable current for the load to avoid damage to the battery due to current fluctuations; the drone will be charged with the LCC-S topology in the later stage of charging. It can provide an output characteristic of approximately constant voltage near the resonant frequency, which is in line with the later stage of battery charging (constant voltage charging stage), avoiding overcharging and protecting the battery.

[0021] When the transmitting coil transmits energy to the receiving coil on this platform, low-frequency transmission is adopted. At this time, the frequency is set to f1. f1 is part of the recommended operating frequency range in the Qi standard formulated by the Wireless Power Consortium. Selecting f1 can ensure compatibility with existing wireless charging devices. When the transmitting coil transmits energy to the receiving coil of the adjacent charging platform, f2 transmission is adopted. The specific setting depends on user needs.

[0022] Specifically, the mutual inductance between the transmitting coil and the receiving coil is the key to determining the performance of the magnetically coupled resonant wireless power transmission circuit. The shape and material properties of the coupling coil directly affect the transmission power and efficiency of the system.

[0023] In terms of the shape selection of the transmitting coil and the receiving coil, a planar spiral coil structure is adopted. When used, it is only necessary to ensure that the coupling coils are coaxial, and it has a relatively ideal quality factor and coupling coefficient.

[0024] In terms of the selection of transmitting coil and receiving coil materials, the main indicators are the self-inductance and high-frequency impedance of the wire. The high-frequency impedance of the planar spiral coil includes two parts: DC resistance and AC impedance. Among them, the DC resistance is determined by the material, winding length and cross-sectional area of ​​the wire, and is expressed as: (1), in, represents the DC resistance of the coil, is the resistivity of the wire, is the number of turns of the coil, is the winding length of the coil, For the wire diameter.

[0025] From formula (1), we can see that in order to reduce the DC resistance of the coil, a wire with a larger diameter and lower resistivity should be selected, and the winding length of the coil should be reduced as much as possible. On this basis, the high-frequency coil also needs to consider the AC impedance generated by the skin effect under high-frequency excitation.

[0026] The AC resistance of a planar spiral coil can be expressed as: (2), in, represents the AC resistance of the coil, is an irrational number, is the vacuum permeability, is the operating frequency, is the conductivity.

[0027] It can be seen from formula (2) that the wire diameter is the main influencing factor of the AC resistance of the planar spiral coil. The larger the wire diameter, the more obvious the skin effect and the larger the AC resistance.

[0028] In order to reduce high-frequency loss and suppress skin effect, Litz wire is used to wind the planar spiral coil. Litz wire is a high-frequency wire made by twisting multiple enameled wires. This process makes the eddy current passing through the wire evenly distributed, thereby achieving even distribution of the induced magnetic field.

[0029] like Figure 2 As shown, the present invention provides a three-dimensional three-layer UAV wireless charging storage charging power maximization control method, comprising the following steps: S1. Build Figure 1 The three-dimensional three-layer UAV wireless charging bank charging power maximization control system shown; specifically: In this embodiment, the height of each charging platform is 50cm, that is, the distance between two adjacent charging platforms is 50cm, and a transmitting coil is laid on each charging platform. When the drone flies into the charging warehouse, energy can be transmitted through the coupling between the transmitting coil and the receiving coil. Both the transmitting coil and the receiving coil are planar spiral coils, where the radius of the transmitting coil is 130mm and the radius of the receiving coil is 80mm.

[0030] S2. Configure resonance according to the size and frequency of the transmitting coil and the receiving coil, and determine the size of the compensation capacitor; specifically: When the system topology is SS topology, the compensation capacitor of the transmitting coil for: (3), Compensation capacitor for receiving coil for: (4), When the system topology is LCC-S, the compensation capacitor of the transmitting coil for: (5), Compensation capacitor for receiving coil for: (6), in, is the self-inductance of the transmitting coil, is the self-inductance of the receiving coil, is the angular frequency, To compensate for the inductance.

[0031] S3. Monitor whether there is a load (drone) on the charging platform. According to the number of loads on the three-layer charging platform, determine the charging scenario and the operating frequency of each layer of transmitting coils and the connection method between the transmitting coils. In each charging scenario, monitor the charging power of each drone and determine the transmitting coil topology according to the power of the drone to maximize the drone charging power of the entire system.

[0032] like Figure 3 As shown, each UAV wireless charging platform includes a magnetically coupled resonant wireless power transmission circuit, a rectifier circuit and a filter circuit connected in sequence. The magnetically coupled resonant wireless power transmission circuit includes a transmitter arranged on the charging platform and a receiver arranged on the UAV. The transmitter includes a transmitting coil and a resonant network thereof, and its resonant network includes LCC resonance and S resonance. The receiving end includes a receiving coil and a resonant network thereof, and its resonant network is S resonance. The DC power supply is converted by a full-bridge inverter to output high-frequency AC power, which is respectively connected to the input ends of the three charging platforms, that is, the high-frequency AC power converted and output by the full-bridge inverter is input to the input end of the magnetically coupled resonant wireless power transmission circuit. The output of the magnetically coupled resonant wireless power transmission circuit is sequentially connected to the rectifier circuit and the filter circuit, wherein the rectifier circuit is composed of four diodes connected to convert AC power into DC power. However, the rectified DC power is not completely smooth, but has a large pulsation component. The filter circuit is composed of a filter capacitor, and the pulsation can be smoothed through the charging and discharging characteristics of the capacitor to output a more stable DC power.

[0033] Specifically, by Figure 4 From (a) to (e), it can be seen that the three-layer charging warehouse of the present invention has five charging scenarios, and the specific monitoring in each charging scenario is as follows: The first charging scenario: All three drones are charging in the warehouse. In this case, the three drones are charged normally until the power of the drone reaches SOC1. The power monitoring circuit sends a signal, and the system topology switches from SS topology to LCC-S topology. Then the three transmitting coils are connected in parallel to maximize the drone charging power of the entire system.

[0034] The second charging scenario: After the drone on the third floor is charged, it flies away from the charging station. The drones on the first and second floors continue to charge. At this time, since the charging platform on the third floor is vacant, the load monitoring circuit sends a signal to switch the frequency of the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and the topology of the third-layer transmitting coil is switched from the LCC topology to the S topology to charge the drone on the second floor. Because the frequencies of the second-layer transmitting coil and the third-layer transmitting coil are different at this time, no interference will occur.

[0035] The third layer of transmitting coil reflected impedance for: (7), in, is the angular frequency corresponding to the auxiliary charging frequency f2, is the mutual inductance between the third-layer transmitting coil and the second-layer receiving coil, is the external circuit impedance of the second layer receiving coil.

[0036] The reflected impedance of the first or second transmitting coil is: (8), in, is the reflected impedance of the first layer transmitting coil or the second layer transmitting coil, is the angular velocity frequency corresponding to the basic charging frequency f1, is the mutual inductance between the first layer transmitting coil or the second layer transmitting coil and the receiving coil of their respective corresponding layers, is the external circuit impedance of the first layer receiving coil or the second layer receiving coil.

[0037] Through simulation, we know that , so .

[0038] Since the three transmitting coils are in parallel at this time, and , so it will cause the input voltage of the third layer transmitting coil to decrease, and then pull down the input voltage of the other two transmitting coils, thereby reducing the charging power of the system. Therefore, it is necessary to change the connection relationship between the transmitting coils at this time, that is, the first layer transmitting coil and the second layer transmitting coil are still connected in parallel, and then connected in series with the third layer transmitting coil to increase the charging power.

[0039] The third charging scenario: The drones on the second floor finish charging and fly away from the charging depot, while the drones on the first and third floors continue to charge. At this time, since the charging platform on the second floor is vacant, the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology to charge the drones on the first and third floors. Since the reflected impedance is very different, the connection method of the transmitting coil is switched to the first-layer transmitting coil and the third-layer transmitting coil in parallel, and then in series with the second-layer transmitting coil to increase the charging power.

[0040] The fourth charging scenario: After the second and third-layer drones are charged, they fly away from the charging station, while the first-layer drones continue to charge. At this time, since the second and third-layer charging platforms are idle, the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The second-layer transmitting coil charges the first-layer drone. At this time, the third-layer transmitting coil may not be able to transmit energy due to the long distance. Since the reflection impedance of the second-layer transmitting coil and the third-layer transmitting coil is very small, the connection method of the coil is switched to the second-layer transmitting coil and the third-layer transmitting coil in parallel, and then in series with the first-layer transmitting coil to increase the charging power.

[0041] The fifth charging scenario: The first and third-layer drones are fully charged and fly away from the charging station, while the second-layer drones continue to charge. At this time, since the first and third-layer charging platforms are idle, the load monitoring circuit sends a signal to switch the frequency of the first-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The first-layer transmitting coil and the third-layer transmitting coil both charge the second-layer drone. Since the reflection impedance of the first-layer transmitting coil and the third-layer transmitting coil is very small, the connection method of the coil is switched to the first-layer transmitting coil and the third-layer transmitting coil in parallel, and then in series with the second-layer transmitting coil to increase the charging power.

[0042] Further: In order to extend the service life of the drone battery and meet the charging curve of the lithium battery, the transmitter sets the control circuit switching topology, as follows: Figure 5 As shown, the transmitting coil topology circuit includes a first switch a, a second switch b, a first capacitor C 1. Second capacitor C 2. The third capacitor C 3. Compensation inductance and the self-inductance of the transmitting coil , the first switch a controls the S topology, the second switch b controls the LCC topology, the first switch a is closed and the second switch b is open, the first capacitor C 1 and the transmitting coil form a closed path with the power supply. When the first switch a is opened and the second switch b is closed, the second capacitor C 2 and the self-inductance of the transmitting coil After connecting in series with the third capacitor C 3 in parallel, and then with the compensation inductor After connecting in series with the power supply U S A closed path is formed; switch a controls the S topology, and switch b controls the LCC topology. When the drone power reaches SOC1, the drone power monitoring circuit sends a signal, opens switch a, closes switch b, and switches the SS topology to the LCC-S topology; when the drone is fully charged, a new low-power drone flies into the drone hangar for charging, and the drone power monitoring circuit sends a signal, opens switch b, closes switch a, and switches the LCC-S topology to the SS topology. The S topology is a compensation capacitor connected in series with the coil, while the LCC topology consists of an inductor and two capacitors. When the drone enters the hangar for charging, the entire system switches from the SS constant current topology to the LCC-S constant voltage topology, which conforms to the charging curve of the drone lithium battery and can extend the life of the drone battery.

[0043] Further: like Figure 6As shown in the figure, a signal is sent by monitoring whether a drone is docked on the charging platform. When a drone is docked on the charging platform, the corresponding transmitting coil frequency is transmitted using the basic charging frequency, i.e., f1. When there is no drone docked on the monitoring charging platform, the monitoring circuit sends a signal, and the transmitting coil frequency is switched from the basic charging frequency f1 to the auxiliary charging frequency f2, transmitting energy to the drone docked on the adjacent charging platform, as shown in the figure. Figure 5 As shown, the charging topology is switched from LCC-S to SS to increase the charging power.

[0044] Specifically, the charging power of each drone is: in is the transmission power between the transmitting coil and the receiving coil when the transmitting coil frequency is the basic charging frequency f1, is the transmission power between the transmitting coil and the receiving coil when the frequency is the auxiliary charging frequency f2. Different high frequency values ​​can be set according to the specific requirements of users.

[0045] The transmission power expression of the coil at the auxiliary charging frequency f2 is: (9), in, is the angular frequency of the auxiliary charging frequency f2, is the mutual inductance between the transmitting coil and the receiving coil, For AC power supply, is the load resistance, is the equivalent internal resistance of the AC power supply, is the internal resistance of the transmitting coil, is the internal resistance of the receiving coil.

[0046] Furthermore, when the frequency is the basic charging frequency f1, before the drone power reaches SOC1, the charging topology is the SS topology. At this time, the transmission power expression between the transmitting coil and the receiving coil is: (10), in, is the angular frequency at the basic charging frequency f1, To compensate for the internal resistance of the coil.

[0047] When the drone reaches SOC1, the charging topology switches to LCC-S topology. At this time, the transmission power expression between the transmitting coil and the receiving coil is: (11), in, To compensate the inductance value, is the compensation capacitance of the transmitting coil.

[0048] From the above analysis, it can be seen that the charging power required by the user can be obtained by simply changing the operating frequency of the transmitting coil.

[0049] Specifically, , Therefore, when the transmitting coils of the adjacent platforms participate in the transmission power, before the UAV power reaches SOC1, (12), When the drone battery reaches SOC1, (13), The present invention realizes the basic task of maximizing power for the application scenario of the UAV charging depot, and uses topology switching and a simple control circuit to improve the output power and application flexibility of the system, effectively improves the stability of the system, and prolongs the service life of the charging equipment.

[0050] The present invention also provides an electronic device, comprising a memory and a processor, wherein: A memory for storing computer programs that can be run on the processor; A processor is used to execute the steps of the control method when running the computer program.

[0051] Although the specific implementation modes of the present invention are described above, those skilled in the art who are familiar with the technical field of the present invention understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A three-dimensional three-layer UAV wireless charging warehouse charging power maximization control system, characterized in that: include: The power circuit and control circuit include a full-bridge inverter and a wireless charging station for unmanned aerial vehicles. The wireless charging station for unmanned aerial vehicles includes a three-layer charging platform. Each charging platform includes a transmitter located on the charging platform, a receiver located on the unmanned aerial vehicle, a rectifier circuit and a filter circuit. The full-bridge inverter outputs three high-frequency alternating currents to the transmitters of the three-layer charging platforms respectively. The transmitter and the receiver are connected by magnetic coupling. The output signal of the receiver passes through the rectifier circuit and the filter circuit in turn to charge the unmanned aerial vehicle. The control circuit includes an inverter dual-frequency output circuit and a monitoring circuit. The inverter dual-frequency output circuit is used to output high-frequency or low-frequency alternating current. The monitoring circuit includes three charging platform monitoring circuits. The three charging platform monitoring circuits are used to monitor the power and quantity of the unmanned aerial vehicles on the three-layer charging platform respectively. The charging frequency, topology and coil connection method of each transmitter are determined according to the monitored power and the number of unmanned aerial vehicles to maximize the unmanned aerial vehicle charging power of the entire system.

2. The three-dimensional three-layer UAV wireless charging station charging power maximization control system according to claim 1 is characterized in that: The frequency of the low-frequency AC power output by the inverter dual-frequency output circuit is the basic charging frequency f1 of the transmitter, and the frequency of the high-frequency AC power is the auxiliary charging frequency f2. The basic charging frequency f1 is used when the transmitter transmits energy to the receiving end on the current charging platform, and the auxiliary charging frequency f2 is used when the transmitter transmits energy to the receiving end of the adjacent charging platform.

3. The three-dimensional three-layer UAV wireless charging station charging power maximization control system according to claim 1 is characterized in that: The transmitting end includes a transmitting coil and a resonant network thereof, and the receiving end includes a receiving coil and a resonant network thereof; The receiving coil topology circuit adopts S topology; When the drone's power is less than SOC1, both the transmitting coil and the receiving coil use the S topology, and the system uses the SS topology for charging; When the drone's power level is greater than SOC1, the transmitting coil switches from the S topology to the LCC topology, and the system uses the LCC-S topology for charging.

4. The three-dimensional three-layer UAV wireless charging station charging power maximization control system according to claim 3 is characterized in that: The coil connection between each transmitting end is as follows: When all three drones are charging in the charging station, the coils of the three transmitters are connected in parallel; When the drones on the third-layer charging platform are fully charged and fly away from the charging station, the drones on the first-layer charging platform and the second-layer charging platform continue to charge; the transmitting coil of the third-layer charging platform charges the drones on the second-layer charging platform, and the first-layer transmitting coil is connected in parallel with the second-layer transmitting coil and then connected in series with the third-layer transmitting coil; When the drones on the second-level charging platform are fully charged and fly away from the charging station, the drones on the first-level and third-level charging platforms continue to charge; the transmitting coil of the second-level charging platform charges the drones on the first-level and third-level charging platforms, and the first-level transmitting coil is connected in parallel with the third-level transmitting coil and then connected in series with the second-level transmitting coil; When the drones on the second and third charging platforms are fully charged and fly away from the charging station, the drones on the first charging platform continue to charge; the second transmitting coil charges the drones on the first charging platform, and the second transmitting coil is connected in parallel with the third transmitting coil and then in series with the first transmitting coil; When the drones on the first and third charging platforms are fully charged and fly away from the charging station, the drones on the second charging platform continue to charge; the first and second transmitting coils both charge the drones on the second charging platform, and the first transmitting coil is connected in parallel with the third transmitting coil and then in series with the second transmitting coil.

5. The three-dimensional three-layer UAV wireless charging station charging power maximization control system according to claim 3 is characterized in that: Both the transmitting coil and the receiving coil adopt a planar spiral coil structure.

6. A control method using the three-dimensional three-layer UAV wireless charging depot charging power maximization control system according to any one of claims 1 to 5, characterized in that: The following steps are involved: Build a three-dimensional three-layer drone wireless charging depot to maximize charging power control system; Configure resonance according to the size and frequency of the transmitting coil and the receiving coil, and determine the size of the compensation capacitor; Monitor whether there is load on the charging platform, and determine five charging scenarios based on the number of loads on the three-layer charging platform; in each charging scenario, monitor the charging power of each drone. When the power of the drone is less than SOC1, the transmitting coil and the receiving coil both adopt the S topology, and the system adopts the SS topology for charging; when the power of the drone is greater than SOC1, the transmitting coil switches from the S topology to the LCC topology, and the system adopts the LCC-S topology for charging; when the drone completes charging and leaves the charging platform, the operating frequency of the transmitting coil on this layer of the charging platform switches to high frequency, and the topology switches to the S topology, so that it can charge the drones on the adjacent charging platform and ultimately maximize the drone charging power of the entire system.

7. The control method according to claim 6, characterized in that: According to the size and frequency of the transmitting coil and the receiving coil, the resonance is configured and the size of the compensation capacitor is determined; specifically: When the system topology is SS topology, the compensation capacitor of the transmitting coil for: ， Compensation capacitor for receiving coil for: ， When the system topology is LCC-S, the compensation capacitor of the transmitting coil for: ， Compensation capacitor for receiving coil for: ， in, is the self-inductance of the transmitting coil, is the self-inductance of the receiving coil, is the angular frequency, To compensate for the inductance.

8. The control method according to claim 6, characterized in that: The five charging scenarios are as follows: The first charging scenario: All three drones are charged in the warehouse. In this case, the three drones are charged normally. When the power of the drone reaches SOC1, the power monitoring circuit sends a signal, and the system topology switches from SS topology to LCC-S topology, and then the three transmitting coils are connected in parallel. The second charging scenario: the drone on the third-layer charging platform is fully charged and flies away from the charging depot, while the drones on the first-layer charging platform and the second-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and the topology of the third-layer transmitting coil is switched from the LCC topology to the S topology to charge the drone on the second-layer charging platform. The first-layer transmitting coil is connected in parallel with the second-layer transmitting coil and then in series with the third-layer transmitting coil; The third charging scenario: the drones on the second-layer charging platform are fully charged and fly away from the charging depot, while the drones on the first-layer and third-layer charging platforms continue to charge; the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switches from the LCC topology to the S topology to charge the drones on the first-layer and third-layer charging platforms. The first-layer transmitting coil is connected in parallel with the third-layer transmitting coil and then connected in series with the second-layer transmitting coil; The fourth charging scenario: the drones on the second-layer charging platform and the third-layer charging platform are fully charged and fly away from the charging depot, while the drones on the first-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the second-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The second-layer transmitting coil charges the drones on the first-layer charging platform, and the second-layer transmitting coil and the third-layer transmitting coil are connected in parallel and then in series with the first-layer transmitting coil; The fifth charging scenario: the drones on the first-layer charging platform and the third-layer charging platform complete charging and fly away from the charging depot, while the drones on the second-layer charging platform continue to charge; the load monitoring circuit sends a signal to switch the frequency of the first-layer transmitting coil and the third-layer transmitting coil from the basic charging frequency f1 to the auxiliary charging frequency f2, and switch from the LCC topology to the S topology. The first-layer and second-layer transmitting coils both charge the drones on the second-layer charging platform. The first-layer transmitting coil and the third-layer transmitting coil are connected in parallel and then in series with the second-layer transmitting coil.

9. The control method according to claim 8, characterized in that: The transmission power between the transmitting coil and the receiving coil when the frequency is the auxiliary charging frequency f2 is obtained by setting different high frequency values ​​according to the specific requirements of the user; specifically: make ,in, is the transmission power between the transmitting coil and the receiving coil when the transmitting coil frequency is the basic charging frequency f1, is the transmission power between the transmitting coil and the receiving coil when the frequency is the auxiliary charging frequency f2; When the transmitting coil of the adjacent charging platform participates in the power transmission, before the drone reaches SOC1: ， in, is the angular frequency at the basic charging frequency f1, is the angular frequency of the auxiliary charging frequency f2, is the mutual inductance between the transmitting coil and the receiving coil, To compensate for the internal resistance of the coil, is the internal resistance of the transmitting coil, is the internal resistance of the receiving coil, is the load resistance; When the drone battery reaches SOC1: ， in, To compensate for the inductance, is the compensation capacitance of the transmitting coil.

10. An electronic device, characterized in that comprising a memory and a processor, wherein: A memory for storing computer programs that can be run on the processor; A processor, configured to execute the steps of the control method as claimed in any one of claims 6 to 9 when running the computer program.

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