Mechanical-electromagnetic energy composite energy supply device and energy supply method

Abstract

The invention discloses a mechanical-electromagnetic energy composite energy supply device, and the device comprises a wireless charging power conversion module which is used for receiving a direct current outputted by an external power supply, and carrying out the processing of the direct current to obtain a high-frequency alternating current; the electromagnetic resonance coupling module is connected with the wireless charging power conversion module and is used for wirelessly transmitting the high-frequency alternating current to obtain first alternating current; the mechanical energy conversion module is used for converting mechanical energy generated by wings of the unmanned aerial vehicle into electric energy; the energy collection module is connected with the mechanical energy conversion module and the electromagnetic resonance coupling module and used for integrating and collecting the first alternating current and the electric energy and transmitting the first alternating current and the electric energy to a load battery of the unmanned aerial vehicle for power supply. According to the invention, wing vibration and friction energy collection structures can be subjected to high-performance integration, an electromagnetic coupling mechanism is lightened, and the bottleneck of efficient mechanical-electromagnetic energy collection, conversion and interconnection power supply of the unmanned aerial vehicle is broken through.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wireless power transmission, and particularly relates to a mechanical-electromagnetic energy composite power supply device and a power supply method. BACKGROUND

[0002] The current power supply methods for unmanned aerial vehicles mainly include self-power generation and site power supply. The common self-power generation method for unmanned aerial vehicles is to carry solar or wind power generation equipment. However, the energy density of the solar or wind power system is small, it is greatly affected by weather factors, and a large area or volume of equipment needs to be installed, which affects the stability of the unmanned aerial vehicle. The site power supply method for unmanned aerial vehicles mainly includes replacing batteries or wired / contact charging. The battery replacement method requires complicated manual / mechanical operation. The wired / contact charging method requires high positioning accuracy for the landing of the unmanned aerial vehicle, and the contact electrode is exposed, which poses a safety risk.

[0003] In addition to the wired / contact charging method, there is also a charging method that converts mechanical energy. During the flight of the unmanned aerial vehicle, there is a lot of mechanical energy loss due to wing vibration, component friction, etc. By using piezoelectric and triboelectric effects to collect and convert the corresponding mechanical energy, the energy utilization efficiency of the unmanned aerial vehicle can be effectively improved, and the endurance of the unmanned aerial vehicle can be further improved without affecting the stability of the unmanned aerial vehicle.

[0004] Compared with the wired / contact charging method, research has found that the electromagnetic resonance coupling wireless power transmission technology has the advantages of flexible and convenient charging, safety and reliability, etc. Its application in unmanned aerial vehicles can avoid the problems of poor convenience, low safety, and weak popularization of traditional methods.

[0005] However, the existing piezoelectric and triboelectric energy collection technology needs to adapt to the mechanical energy dissipation characteristics of the unmanned aerial vehicle, meet the power supply interface conversion requirements, and unreasonable layout architecture and integration method will affect the normal operation of the unmanned aerial vehicle, and cannot efficiently collect the mechanical energy of the unmanned aerial vehicle. At the same time, random errors such as positioning errors, adjustment errors, and air flow effects in the autonomous control process of the unmanned aerial vehicle will cause greater deviation of the power supply and power receiving ends with a relative position that is not fixed based on electromagnetic resonance coupling, resulting in a large electromagnetic coupling fluctuation range, making it difficult to ensure the stability and efficiency of the charging, and the lightweight body of the unmanned aerial vehicle limits the volume and weight of the power receiving end. Therefore, how to adapt to the mechanical energy dissipation characteristics and interface conversion requirements of the unmanned aerial vehicle, improve the piezoelectric and triboelectric energy collection performance, and improve the freedom of efficient and stable wireless charging under the conditions of random coupling and lightweight power receiving to realize high-performance piezoelectric and triboelectric energy collection and electromagnetic resonance composite power supply is the key scientific and technological problem faced by the present research. SUMMARY

[0006] The mechanical-electromagnetic energy composite power supply device and the power supply method can realize high-performance integration of wing vibration and friction energy collection structures, and light-weight electromagnetic coupling mechanism, and break through the bottleneck of mechanical-electromagnetic energy efficient collection, conversion and interconnection power supply of the unmanned aerial vehicle.

[0007] To achieve the above object, the application adopts the following technical solutions: In a first aspect, the application provides a mechanical-electromagnetic energy composite power supply device, comprising: a wireless charging power conversion module, an electromagnetic resonance coupling module, a mechanical energy conversion module and an energy collection module. The wireless charging power conversion module is configured to receive direct current output by an external power supply and process the direct current to obtain high-frequency alternating current. The electromagnetic resonance coupling module is connected with the wireless charging power conversion module and is configured to wirelessly transmit the high-frequency alternating current to obtain first alternating current. The mechanical energy conversion module is configured to convert mechanical energy generated by the wing of the unmanned aerial vehicle into electrical energy, wherein the electrical energy includes piezoelectric energy and frictional electricity. The energy collection module is connected with the mechanical energy conversion module and the electromagnetic resonance coupling module and is configured to integrate and collect the first alternating current and the electrical energy and transmit the integrated and collected electrical energy to a load battery of the unmanned aerial vehicle for power supply.

[0008] Optionally, the wireless charging power conversion module comprises an overvoltage and overcurrent protection unit, a high-frequency inverter unit, a driving unit, a control unit and an auxiliary power supply unit. The overvoltage and overcurrent protection unit is configured to receive direct current output by an external power supply and perform overvoltage and overcurrent protection to output initial direct current. The high-frequency inverter unit is connected with the overvoltage and overcurrent protection unit and is configured to convert the initial direct current output by the overvoltage and overcurrent protection unit into high-frequency alternating current and transmit the high-frequency alternating current to the electromagnetic resonance coupling module. The control unit adopts a phase-locked loop frequency tracking control strategy, outputs a pulse signal and tracks the maximum output efficiency point of the high-frequency alternating current to cope with frequency splitting and resonance mismatch phenomena generated in the working range. The input end of the driving unit is connected with the control unit, and the output end of the driving unit is connected with the high-frequency inverter unit, so as to generate a gate driving signal according to the pulse signal and control the on-off of the switch tube of the high-frequency inverter unit. The input end of the auxiliary power supply unit is connected with the overvoltage and overcurrent protection unit, and the output end of the auxiliary power supply unit is connected with the control unit and the driving unit, so as to step down the initial direct current output by the overvoltage and overcurrent protection unit and transmit the stepped-down direct current to the driving unit and the control unit for power supply.

[0009] Optionally, the electromagnetic resonance coupling module comprises: a first electromagnetic resonance compensation topology, a magnetic coupling mechanism, and a second electromagnetic resonance compensation topology connected in sequence; the magnetic coupling mechanism comprises a power supply coil and a power receiving coil; the first electromagnetic resonance compensation topology is connected with the power supply coil, and the second electromagnetic resonance compensation topology is connected with the power receiving coil; the first electromagnetic resonance compensation topology and the second electromagnetic resonance compensation topology are LCC compensation networks and S compensation networks respectively.

[0010] Optionally, the power supply coil in the magnetic coupling mechanism is composed of multiple types of windings, and a magnetic core is added in the power supply coil; the power receiving coil in the magnetic coupling mechanism adopts a printed circuit winding; the winding material of the power supply coil is a Litz wire, the magnetic core material of the power supply coil is a ferrite, and the winding material of the power receiving coil is a printed circuit board.

[0011] Optionally, the electromagnetic resonance coupling module further comprises: a first monitoring unit and a second monitoring unit; the first monitoring unit is connected to the first electromagnetic resonance compensation topology and the power supply coil, and is used for monitoring the voltage and temperature of the first electromagnetic resonance compensation topology and the power supply coil, and alarming when an abnormality occurs; the second monitoring unit is connected to the second electromagnetic resonance compensation topology and the power receiving coil, and is used for monitoring the voltage and temperature of the second electromagnetic resonance compensation topology and the power receiving coil, and alarming when an abnormality occurs; the first monitoring unit comprises a first monitoring subunit and a first alarm subunit connected in sequence; the second monitoring unit comprises a second monitoring subunit and a second alarm subunit connected in sequence.

[0012] Optionally, the mechanical energy conversion module comprises: a piezoelectric energy collection unit and a friction nanogenerator; the piezoelectric material and the friction nanogenerator are both arranged inside the wing of the unmanned aerial vehicle, and are respectively used for converting the deformation and friction of the wing into piezoelectric energy and triboelectric energy.

[0013] Optionally, the energy collection module comprises a low-frequency rectification unit, an energy equalization unit, a rectification unit, an impedance matching circuit, and a load battery. The low-frequency rectification unit is connected with the mechanical energy conversion module, and is used for converting the piezoelectric energy and the triboelectric energy into first direct current. The rectification unit is connected with the second electromagnetic resonance compensation topology, and is used for rectifying the first alternating current to convert it into second direct current. The energy equalization unit is connected with the rectification unit and the low-frequency rectification unit, and is used for equalizing the intermittent second direct current and the first direct current to obtain third direct current. The impedance matching circuit is connected with the output end of the energy equalization unit, and is used for adaptively adjusting the equivalent impedance of the circuit to make the charging efficiency optimal, and delivering the third direct current passing through the impedance matching circuit to the load battery of the unmanned aerial vehicle for charging.

[0014] Optionally, the energy balancing unit comprises a capacitor and a switch connected in series, a control circuit and a detection subunit; the capacitor is used for storing the second DC power and the first DC power; the detection subunit is used for acquiring the voltage and the current of the capacitor; the control circuit is connected with the detection subunit and the switch, and is used for outputting a control signal of the switch according to the voltage and the current of the capacitor and a judgment rule, and controlling the opening and closing of the switch; the judgment rule comprises: temporarily closing the switch when the voltage of the capacitor exceeds a set threshold voltage, and otherwise not closing the switch; after the switch is temporarily closed, disconnecting the switch when the power of the capacitor is less than a set threshold power, and otherwise keeping the switch closed.

[0015] Optionally, the wireless charging power conversion module, the first electromagnetic resonance compensation topology, the power supply coil and the first monitoring unit are arranged on the ground; the power receiving coil, the second electromagnetic resonance compensation topology, the second monitoring unit, the mechanical energy conversion module and the energy collection module are arranged on the unmanned aerial vehicle.

[0016] In the second aspect, the application provides a power supply method applied to the mechanical-electromagnetic energy composite power supply device in the first aspect, comprising: Based on the wireless charging power conversion module, receiving the DC power output by the external power supply and processing the DC power to obtain high-frequency AC power; Using the electromagnetic resonance coupling module to wirelessly transmit the high-frequency AC power to obtain first AC power; Converting the mechanical energy generated by the wings of the unmanned aerial vehicle into electrical energy; wherein the electrical energy comprises piezoelectric energy and triboelectric energy; Based on the energy collection module, integrating and collecting the first AC power and the electrical energy, and transmitting the integrated and collected power to the load battery of the unmanned aerial vehicle for power supply.

[0017] Compared with the prior art, the application has the following beneficial effects: The application provides a mechanical-electromagnetic energy composite power supply device and a power supply method, wherein two power supply modes are provided for composite power supply, the first mode is to convert the direct current output by an external power supply into high-frequency alternating current through a wireless charging power conversion module and an electromagnetic resonance coupling module connected with the wireless charging power conversion module, and then to obtain first alternating current through wireless transmission, the second mode is to convert mechanical energy generated by a wing of an unmanned aerial vehicle into electric energy (piezoelectric energy and frictional electric energy) through a mechanical energy conversion module, and finally, the device is provided with an energy collection module to integrate and collect the first alternating current and the electric energy output by the two power supply modes, and to stably and composite power supply, the mechanical-electromagnetic energy composite power supply device can provide energy supply for the unmanned aerial vehicle in the whole working cycle through the combination of mechanical energy (piezoelectric and frictional energy) collection and wireless electric energy transmission technology, can greatly improve the energy utilization efficiency of the unmanned aerial vehicle, can provide efficient and flexible electric energy supply mode for the unmanned aerial vehicle, is favorable for solving the energy supply problem of the unmanned aerial vehicle, prolonging the autonomous operation time and distance of the unmanned aerial vehicle, and reducing the dependence of the unmanned aerial vehicle on energy storage batteries.

[0018] The application provides a mechanical-electromagnetic energy composite power supply device and a power supply method, wherein the electromagnetic resonance coupling module in the device comprises a first electromagnetic resonance compensation topology, a magnetic coupling mechanism (a power supply coil and a power receiving coil) and a second electromagnetic resonance compensation topology connected in sequence, the magnetic coupling mechanism adopts an asymmetric design, the power supply coil is composed of multiple types of windings, the influence of deviation on the magnetic coupling of the power supply end and the power receiving end can be reduced, and a magnetic core is added for magnetic shielding and magnetic aggregation, the power receiving coil adopts a lightweight design, and the amount of litz wire used in the hard brush circuit winding is reduced to reduce the airborne weight and prolong the endurance distance.

[0019] The application provides a mechanical-electromagnetic energy composite power supply device and a power supply method, wherein the mechanical energy conversion module in the device converts the deformation and friction of the wing into piezoelectric energy and frictional electric energy through a piezoelectric energy collection unit and a frictional nanometer generator, the piezoelectric energy collection unit in the mechanical energy conversion module is subjected to modal analysis and harmonic response analysis through finite element simulation, and the wing structure design suitable for the vibration characteristics of the unmanned aerial vehicle is realized.

[0020] The application provides a mechanical-electromagnetic energy composite power supply device and a power supply method, wherein the control unit in the wireless charging power conversion module in the device adopts a phase-locked loop frequency tracking control strategy to track the maximum output efficiency point of the electromagnetic resonance coupling module, so as to cope with the frequency splitting and resonance mismatch phenomena generated in the working process of the unmanned aerial vehicle. This invention provides a mechanical-electromagnetic energy composite power supply device and power supply method. The energy equalization module within the energy harvesting module of the device can monitor the capacitor voltage in real time, enabling the distribution of electrical energy collected through the two methods. An impedance matching circuit can adaptively adjust the circuit's equivalent impedance to achieve optimal control of the drone's charging efficiency.

[0021] This invention provides a mechanical-electromagnetic energy composite power supply device and power supply method. In the device, the high-frequency inverter unit, energy equalization unit, and impedance matching circuit are controlled by controllable switching transistors, and a composite material made of carbon nanotubes and thermally conductive silicone grease is used to enhance the heat dissipation capacity of the controllable switching transistors. Attached Figure Description

[0022] Figure 1 The diagram shown is a modular frame diagram of a mechanical-electromagnetic energy composite power supply device in one embodiment of the present invention. Figure 2 The diagram shown is a schematic diagram of the phase-locked loop frequency tracking control strategy structure in one embodiment of the present invention; Figure 3 The diagram shown is a schematic representation of the location of the piezoelectric energy harvesting unit in one embodiment of the present invention. Figure 4 The diagram shown is a schematic representation of the structure of a piezoelectric energy harvesting unit in one embodiment of the present invention. Figure 5 The figure shown is a schematic diagram of an asymmetric coupled coil cross-section model in one embodiment of the present invention; Figure 6 The diagram shown is a structural schematic of an energy harvesting module in one embodiment of the present invention. Detailed Implementation

[0023] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0024] Example 1

[0025] like Figure 1 As shown in the figure, this embodiment of the invention introduces a mechanical-electromagnetic energy composite power supply device, including: a wireless charging power conversion module, an electromagnetic resonance coupling module, a mechanical energy conversion module, and an energy harvesting module; The wireless charging power conversion module is used to receive DC power output from an external power source and process it to obtain high-frequency AC power. The electromagnetic resonance coupling module is connected to the wireless charging power conversion module and is used to wirelessly transmit high-frequency AC power to obtain the first AC power. The mechanical energy conversion module is configured to convert mechanical energy generated by the wings of the unmanned aerial vehicle into electrical energy; wherein the electrical energy comprises piezoelectric energy and frictional energy. The energy collection module is connected with the mechanical energy conversion module and the electromagnetic resonance coupling module, and is configured to integrate and collect the first alternating current and the electrical energy, and transmit the integrated and collected electrical energy to a load battery of the unmanned aerial vehicle for power supply.

[0026] The mechanical-electromagnetic energy composite power supply device is constructed by the mechanical energy conversion module, the wireless charging power conversion module, the electromagnetic resonance coupling module and the energy collection module, and can greatly improve the energy utilization efficiency of the unmanned aerial vehicle, provide an efficient and flexible power supply mode for the unmanned aerial vehicle, and is beneficial to solving the energy supply problem of the unmanned aerial vehicle, prolonging the autonomous operation time and distance of the unmanned aerial vehicle, and reducing the dependence of the unmanned aerial vehicle on the energy storage battery.

[0027] In the embodiment, as shown in Figure 1 The wireless charging power conversion module comprises a over-voltage and over-current protection unit, a high-frequency inverter unit, a driving unit, a control unit and an auxiliary power supply unit. The over-voltage and over-current protection unit is configured to receive direct current output by an external power supply, and perform over-voltage and over-current protection to output initial direct current; in the embodiment, the over-voltage and over-current protection unit can be selected from a TVS diode, a voltage-dependent resistor (MOV), a voltage stabilizing resistor, a fuse, a current / voltage relay and the like, to detect whether the direct current (voltage and current) output by the external power supply is safe, and cut off when the voltage and current are too high, thereby providing protection for the entire device. The high-frequency inverter unit is connected with the over-voltage and over-current protection unit, and is configured to convert the initial direct current output by the over-voltage and over-current protection unit into high-frequency alternating current, and transmit the high-frequency alternating current to the electromagnetic resonance coupling module; wherein the high-frequency inverter unit is a full-bridge inverter circuit or a half-bridge inverter circuit. The control unit adopts a phase-locked loop frequency tracking control strategy, and outputs a pulse signal to track the maximum output efficiency point of the high-frequency alternating current, so as to cope with frequency splitting and resonance mismatch phenomena generated in the working range. The input end of the driving unit is connected with the control unit, and the output end of the driving unit is connected with the high-frequency inverter unit, and the driving unit is configured to generate a gate driving signal according to the pulse signal, and control the on-off of the switch tube of the high-frequency inverter unit. The input end of the auxiliary power supply unit is connected with the over-voltage and over-current protection unit, and the output end of the auxiliary power supply unit is connected with the control unit and the driving unit, and the auxiliary power supply unit is configured to step down the initial direct current output by the over-voltage and over-current protection unit, and transmit the stepped-down direct current to the driving unit and the control unit for power supply.

[0028] Specifically, refer to Figure 2The diagram includes a DC power supply (external DC power supply), an overvoltage and overcurrent protection unit, a drive unit, a high-frequency inverter unit, a control unit, and a first electromagnetic resonance compensation topology (including the power supply coil L). t series resistor R t and capacitor C t ) and power supply coil L t The high-frequency inverter unit uses a single-phase full-bridge inverter circuit. In the diagram, C1 represents a resistor, and S... 1、 S 2、 S 3、 S4 represents the four switching transistors of the high-frequency inverter unit; the control unit includes a current acquisition module, a zero-crossing detection module, a digital phase detector, a frequency measurement module, a fuzzy PI control module, and a microprocessor. The specific connection methods are not detailed here but can be found in [reference needed]. Figure 2 Or the following is the workflow of the control unit: The current acquisition module acquires the current signal of the high-frequency AC power output from the high-frequency inverter unit. i 1( θ ), and transmit it to the zero-crossing detection module; The zero-crossing detection module receives the current signal. i 1( θ It extracts the zero-crossing point (phase reference) of the current signal and outputs the current signal. i 1( θ Square wave synchronization signal with the same frequency and phase u i ( θ ); Square wave synchronization signal u i ( θ and system clock f s The input frequency measurement module (counter) counts, and the output represents the system clock. f s Synchronization signal with square wave u i ( θ ) Count values ​​of frequency relationship N 0; Square wave synchronization signal u i ( θ and reference frequency signal u o ( θ The input is compared with the digital phase detector, and the output is a phase error pulse signal Δθ; Based on phase error Δ θ System clock f s and count value N0, the fuzzy PI control module adjusts the PWM frequency according to the phase error, and controls the phase error Δ θ For zero, the resonance frequency point tracking is realized, and the reference frequency signal is output u o ( θ ); The reference frequency signal u o ( θ ) is input into the microprocessor for processing, to generate a PWM drive signal (pulse signal) with the same frequency as the reference frequency signal V GS , so as to realize the on-off control of the switching tube in the high-frequency inverter unit.

[0029] The drive unit generates a gate drive signal of the switching tube based on the PWM drive signal.

[0030] Specifically, the control unit adopts a phase-locked loop frequency tracking control strategy to track the maximum output efficiency point of the high-frequency alternating current of the electromagnetic resonance coupling module. The phase-locked loop can track the phase of the transmitting coil current, and then generate a pulse voltage consistent with the current frequency and phase through fuzzy PI control, to drive the switching tube to turn on and off, so that the power supply device works at the resonance frequency. This strategy can handle the frequency splitting and resonance mismatch phenomena occurring within the operating range, and complete the adaptive regulation of the high-frequency alternating current frequency.

[0031] In this embodiment, the reference Figure 1 , the electromagnetic resonance coupling module comprises: a first electromagnetic resonance compensation topology, a magnetic coupling mechanism and a second electromagnetic resonance compensation topology connected in sequence; the magnetic coupling mechanism comprises a power supply coil and a power receiving coil; the first electromagnetic resonance compensation topology is connected with the power supply coil, and the second electromagnetic resonance compensation topology is connected with the power receiving coil; the first electromagnetic resonance compensation topology and the second electromagnetic resonance compensation topology are LCC compensation networks and S compensation networks respectively.

[0032] Specifically, the LCC compensation network is composed of an inductor connected in series with the power supply coil, a capacitor connected in series with the power supply coil and a capacitor connected in parallel with the power supply coil, forming a T-shaped structure; the S compensation network is composed of a capacitor connected in series with the power supply coil; Specifically, the magnetic coupling mechanism adopts an asymmetric design; wherein, the power supply coil is composed of multiple types of windings, which reduces the influence of the power receiving coil deviating from the center of the power supply coil on the magnetic coupling of the power supply and receiving ends, and adds a magnetic core for magnetic shielding and magnetic aggregation; the power receiving coil adopts a lightweight design, does not use ferrite, and uses a printed circuit winding to reduce the amount of litz wire to reduce the airborne weight to extend the endurance mileage.

[0033] Specifically, the reference Figure 5, asymmetric coupling coil (power supply coil and receiver coil) cross-sectional model schematic diagram, in which, TX represents the power supply end, RX represents the power receiving end, r tr is the inner diameter of the power supply coil, r tw is the difference between the outer diameter and the inner diameter of the power supply coil, w i is the width of each winding of the power supply coil, t is the height of each winding, r ri is the inner diameter of the power receiving coil, r rw is the difference between the outer diameter and the inner diameter of the power receiving coil, h is the vertical distance between the power receiving coil and the power supply coil, and the winding layer of the power supply end represents several layers. In the coupling coil, the power supply coil adopts a winding combination structure (windings 1-7), and the power receiving coil (winding 11) adopts a lightweight structure, i.e. printed circuit winding, to meet the purpose of high-efficiency and stable power reception of the unmanned system in a larger coupling fluctuation range and the purpose of reducing the weight of the unmanned system to prolong the endurance distance.

[0034] Specifically, the first and second electromagnetic resonance compensation topologies are suitable for anti-coupling fluctuation parameter optimization strategies. By finite element simulation, the number of turns, outer diameter, inner diameter of the power receiving coil, and the structure of the transmitting coil can be changed to find the coupling mechanism parameters at which the coupling coefficient fluctuation is the smallest. This can improve the anti-coupling fluctuation performance of the coupling mechanism and expand the stable and efficient power reception range of the unmanned system.

[0035] For example, in combination with the coupling coil interface shown in Figure 5 , first, a finite element simulation model is established to separately simulate and analyze the coupling characteristics of windings 1-7 and winding 11 of the power supply end; then the coupling characteristics of windings 1-7 and winding 11 are superimposed, i.e. the coupling characteristics of the power supply coil as a whole and the power receiving coil are obtained; then set the ratio of the one-way offset tolerance to the radius of the power supply coil, i.e. the offset tolerance, as the optimization goal, wherein the one-way offset tolerance refers to the offset distance when the power receiving coil is offset in a specified direction and the mutual inductance with the power supply coil decreases to 70% of the peak value; by adjusting the parameters in Figure 5 , the offset tolerance under different structural parameters is obtained; finally, the Pareto optimization method is used to obtain a non-inferior solution set of the power supply coil structural parameters, and the winding combination power supply coil structure and parameters are determined from the set to maximize the offset tolerance.

[0036] Specifically, the power supply coil and the power receiving coil and the first and second electromagnetic resonance compensation topologies are configured with parameters, and under the high-frequency alternating current frequency output by the high-frequency inverter unit of the wireless charging power variation module, strong coupling phenomenon occurs, realizing efficient transmission of wireless electric energy.

[0037] In the embodiment, the electromagnetic resonance coupling module further comprises a first monitoring unit and a second monitoring unit; the first monitoring unit is connected to the first electromagnetic resonance compensation topology and the power supply coil, and is used for monitoring the voltage and temperature of the first electromagnetic resonance compensation topology and the power supply coil, and alarming when an abnormality occurs; the second monitoring unit is connected to the second electromagnetic resonance compensation topology and the power receiving coil, and is used for monitoring the voltage and temperature of the second electromagnetic resonance compensation topology and the power receiving coil, and alarming when an abnormality occurs; the first monitoring unit comprises a first monitoring subunit and a first alarm subunit connected in sequence; and the second monitoring unit comprises a second monitoring subunit and a second alarm subunit connected in sequence.

[0038] Specifically, the first monitoring subunit and the second monitoring subunit each comprise a voltage sensor and a temperature sensor, and the first alarm subunit and the second alarm subunit each comprise an LED lamp and a buzzer.

[0039] In the embodiment, the first monitoring subunit and the second monitoring subunit each comprise a voltage sensor and a temperature sensor, and the first alarm subunit and the second alarm subunit each comprise an LED lamp and a buzzer. Figure 1 The mechanical energy conversion module comprises a friction nanogenerator and a piezoelectric energy collection unit, and the piezoelectric material and the friction nanogenerator are arranged inside the wing of the unmanned aerial vehicle, and are respectively used for converting the deformation and friction of the wing into piezoelectric energy and triboelectric energy. Specifically, the piezoelectric energy collection unit uses a composite piezoelectric material, and a dual filler is embedded in an organic polymer base material, so as to effectively improve the piezoelectric output performance of the composite material.

[0040] Specifically, the piezoelectric energy collection unit performs modal analysis and harmonic response analysis by using a numerical analysis software Wolfram Mathematica and a finite element analysis software Ansys, and obtains a structure and parameters suitable for the wing vibration characteristics. Reference Figure 3 and Figure 4 In the embodiment, the piezoelectric energy collection unit is installed inside the wing, and can capture a large amount of mechanical energy dissipated by the wing vibration of the unmanned aerial vehicle, and convert the mechanical energy into electrical energy. The piezoelectric energy collection unit is composed of a piezoelectric ceramic layer for realizing mechanical energy-electrical energy conversion, a thin film battery layer for storing electrical energy, and a central metal gasket layer for providing structural support force, and the sequence is piezoelectric ceramic layer-thin film battery layer-metal gasket layer-thin film battery layer-piezoelectric ceramic layer. When the wing of the unmanned system vibrates, the piezoelectric ceramic layer generates electrical energy, and the collected energy is stored in the battery layer.

[0041] Specifically, the friction nanogenerator selects a friction material with stronger triboelectric effect suitable for the working condition of the wing, and the surface morphology of the friction material is designed by etching, template printing, nano-imprinting and other methods, so as to increase the surface roughness, effective contact area and surface charge density of the friction material, and the doping and thin film technology in the MEMS process is used to improve the anti-interference ability of the electrode.

[0042] In the present embodiment, reference is made to Figure 1 , the energy collection module includes a low-frequency rectification unit, an energy balancing unit, a rectification unit, an impedance matching circuit and a load battery; The low-frequency rectification unit is connected with the mechanical energy conversion module, for converting piezoelectric energy and triboelectric energy into first direct current; The rectification unit is connected with the second electromagnetic resonance compensation topology, for rectifying the first alternating current and converting it into second direct current; The energy balancing unit is connected with the rectification unit and the low-frequency rectification unit, for balancing the intermittent second direct current and the first direct current to obtain third direct current; The impedance matching circuit is connected with the output end of the energy balancing unit, for adaptively adjusting the equivalent impedance of the circuit to make the charging efficiency optimal, and delivering the third direct current passing through the impedance matching circuit to the load battery of the unmanned aerial vehicle for charging.

[0043] Specifically, the energy balancing unit includes a capacitor and a switch connected in series, a control circuit for controlling the switch and a detection subunit; the capacitor is used for storing the second direct current and the first direct current; the detection subunit is used for acquiring the voltage and current of the capacitor; the control circuit is connected with the detection subunit and the switch, and is used for outputting a control signal of the switch according to the voltage and current of the capacitor and a judgment rule to control the opening and closing of the switch; the judgment rule includes temporarily closing the switch when the voltage of the capacitor exceeds a set threshold voltage, and otherwise not closing the switch; after the switch is temporarily closed, the switch is disconnected if the power of the capacitor is less than a set threshold power, and otherwise the switch is kept closed.

[0044] Specifically, reference is made to Figure 6 The piezoelectric energy collection unit and the friction nanogenerator in the mechanical energy conversion module can realize the conversion of mechanical energy into electrical energy dissipated by the wing vibration of the unmanned aerial vehicle, but the output does not meet the power supply requirements of the unmanned system, which is intermittent and unstable. The energy balancing unit can distribute the electrical energy collected in two ways. First, the piezoelectric and friction energy and the electrical energy collected by wireless charging are converted into direct current by the rectification unit, and then flow into the capacitor in the energy balancing unit for energy storage. The control circuit in the energy balancing unit controls the switch signal according to the capacitor voltage monitored by the detection subunit (not shown in Figure 6 ), specifically: temporarily close the switch when the set threshold voltage is exceeded, and if the input power is less than the set threshold power, disconnect the switch, otherwise keep the switch closed; the electrical energy then flows into the impedance matching circuit, which can adaptively adjust the equivalent impedance of the circuit to make the charging efficiency optimal, and finally charges the load battery.

[0045] In the embodiment, the wireless charging power conversion module, the first electromagnetic resonance compensation topology, the power supply coil and the first monitoring unit are arranged on the ground; the power receiving coil, the second electromagnetic resonance compensation topology, the first monitoring unit, the mechanical energy conversion module and the energy collection module are arranged on the unmanned aerial vehicle.

[0046] Embodiment 2

[0047] The embodiment provides an energy supply method applied to the mechanical-electromagnetic energy composite energy supply device in embodiment 1, and the method comprises the following steps of: S1: receiving direct current output by an external power supply based on the wireless charging power conversion module and processing the direct current to obtain high-frequency alternating current; S2: wirelessly transmitting the high-frequency alternating current by using the electromagnetic resonance coupling module to obtain first alternating current; S3: converting mechanical energy generated by the unmanned aerial vehicle wing into electrical energy; wherein the electrical energy comprises piezoelectric energy and triboelectric energy; S4: integrating and collecting the first alternating current and the electrical energy based on the energy collection module and transmitting the first alternating current and the electrical energy to a load battery of the unmanned aerial vehicle to supply power.

[0048] The embodiments of the present application are described above with reference to the drawings, but the present application is not limited to the specific embodiments described above, and the specific embodiments described above are only illustrative but not restrictive, and those skilled in the art can make many forms under the inspiration of the present application without departing from the purpose of the present application and the scope protected by the claims, and these all belong to the protection of the present application.

Claims

1. A mechanical-electromagnetic energy composite power supply device, characterized in that, include: Wireless charging power conversion module, electromagnetic resonance coupling module, mechanical energy conversion module and energy harvesting module; The wireless charging power conversion module is used to receive DC power output from an external power source and process it to obtain high-frequency AC power. The electromagnetic resonance coupling module is connected to the wireless charging power conversion module and is used to wirelessly transmit high-frequency AC power to obtain the first AC power. The mechanical energy conversion module is used to convert the mechanical energy generated by the drone's wings into electrical energy; Electrical energy includes piezoelectric energy and triboelectric energy; The energy harvesting module is connected to the mechanical energy conversion module and the electromagnetic resonance coupling module, and is used to integrate and collect the first AC power and electrical energy, and transmit them to the drone's load battery for power supply.

2. The mechanical-electromagnetic energy composite power supply device according to claim 1, characterized in that, The wireless charging power conversion module includes: an overvoltage and overcurrent protection unit, a high-frequency inverter unit, a drive unit, a control unit, and an auxiliary power supply unit; The overvoltage and overcurrent protection unit is used to receive DC power output from an external power source, perform overvoltage and overcurrent protection, and output initial DC power. The high-frequency inverter unit is connected to the overvoltage and overcurrent protection unit and is used to convert the initial DC power passing through the overvoltage and overcurrent protection unit into high-frequency AC power and supply it to the electromagnetic resonance coupling module. The control unit adopts a phase-locked loop frequency tracking control strategy, and outputs pulse signals to track the maximum output efficiency point of the high-frequency AC power in order to cope with frequency splitting and resonance mismatch phenomena that occur within the working range. The input terminal of the drive unit is connected to the control unit, and the output terminal is connected to the high-frequency inverter unit. It is used to generate a gate drive signal according to the pulse signal to control the switching transistors of the high-frequency inverter unit. The input terminal of the auxiliary power supply unit is connected to the overvoltage and overcurrent protection unit, and the output terminal is connected to the control unit and the drive unit. It is used to step down the initial DC power that has passed through the overvoltage and overcurrent protection unit and supply it to the drive unit and the control unit for power supply.

3. The mechanical-electromagnetic energy composite power supply device according to claim 2, characterized in that, The electromagnetic resonance coupling module includes: a first electromagnetic resonance compensation topology, a magnetic coupling mechanism, and a second electromagnetic resonance compensation topology connected in sequence; the magnetic coupling mechanism includes a power supply coil and a power receiving coil; the first electromagnetic resonance compensation topology is connected to the power supply coil, and the second electromagnetic resonance compensation topology is connected to the power receiving coil; the first electromagnetic resonance compensation topology and the second electromagnetic resonance compensation topology are respectively LCC compensation network and S compensation network.

4. The mechanical-electromagnetic energy composite power supply device according to claim 3, characterized in that, The power supply coil in the magnetic coupling mechanism is composed of multiple types of windings, and a magnetic core is added to the power supply coil; the receiving coil in the magnetic coupling mechanism adopts printed circuit windings; the winding material of the power supply coil is Litz wire, the magnetic core material of the power supply coil is ferrite, and the winding material of the receiving coil is printed circuit board.

5. The mechanical-electromagnetic energy composite power supply device according to claim 3, characterized in that, The electromagnetic resonance coupling module further includes: a first monitoring unit and a second monitoring unit; the first monitoring unit is connected to a first electromagnetic resonance compensation topology and a power supply coil, used to monitor the voltage and temperature of the first electromagnetic resonance compensation topology and the power supply coil, and to issue an alarm when an abnormality occurs; the second monitoring unit is connected to a second electromagnetic resonance compensation topology and a power receiving coil, used to monitor the voltage and temperature of the second electromagnetic resonance compensation topology and the power receiving coil, and to issue an alarm when an abnormality occurs; the first monitoring unit includes a first monitoring subunit and a first alarm subunit connected in sequence; the second monitoring unit includes a second monitoring subunit and a second alarm subunit connected in sequence.

6. The mechanical-electromagnetic energy composite power supply device according to claim 5, characterized in that, The mechanical energy conversion module includes a piezoelectric energy harvesting unit and a triboelectric nanogenerator; the piezoelectric material and the triboelectric nanogenerator are both installed inside the wing of the UAV, and are used to convert the deformation and friction of the wing into piezoelectric energy and triboelectric energy, respectively.

7. The mechanical-electromagnetic energy composite power supply device according to claim 6, characterized in that, The energy harvesting module includes a low-frequency rectification unit, an energy equalization unit, a rectification unit, an impedance matching circuit, and a load battery; The low-frequency rectifier unit is connected to the mechanical energy conversion module and is used to convert piezoelectric energy and triboelectric energy into a first direct current. The rectifier unit is connected to the second electromagnetic resonance compensation topology and is used to rectify the first AC power and convert it into the second DC power. The energy balancing unit is connected to the rectifier unit and the low-frequency rectifier unit to balance the intermittent second DC power and the first DC power to obtain the third DC power. The impedance matching circuit is connected to the output of the energy balancing unit and is used to adaptively adjust the equivalent impedance of the circuit to optimize the charging efficiency and deliver the third DC power through the impedance matching circuit to the drone's load battery for charging.

8. The mechanical-electromagnetic energy composite power supply device according to claim 7, characterized in that, The energy equalization unit includes a capacitor and a switch connected in series, as well as a control circuit and a detection subunit for controlling the switch; the capacitor is used to store a second DC current and a first DC current; the detection subunit is used to acquire the voltage and current of the capacitor; the control circuit is connected to the detection subunit and the switch, and is used to output a control switch signal based on the voltage and current of the capacitor and a judgment rule to control the opening and closing of the switch. The judgment rules include: when the capacitor voltage exceeds the set threshold voltage, the switch is temporarily closed; otherwise, the switch is not closed. After the switch is temporarily closed, if the power of the capacitor is less than the set threshold power, the switch will be opened; otherwise, the switch will remain closed.

9. The mechanical-electromagnetic energy composite power supply device according to claim 8, characterized in that, The wireless charging power conversion module, the first electromagnetic resonance compensation topology, the power supply coil, and the first monitoring unit are all located on the ground; the power receiving coil, the second electromagnetic resonance compensation topology, the second monitoring unit, the mechanical energy conversion module, and the energy harvesting module are all located on the UAV.

10. A method for supplying energy to a mechanical-electromagnetic energy composite power supply device as described in any one of claims 1-9, characterized in that, include: The wireless charging power conversion module receives DC power from an external power source and processes it to obtain high-frequency AC power. The first AC current is obtained by wirelessly transmitting high-frequency AC current using an electromagnetic resonance coupling module; Convert the mechanical energy generated by the drone's wings into electrical energy; Electrical energy includes piezoelectric energy and triboelectric energy; The energy harvesting module integrates and collects the first AC current and electrical energy, and transmits it to the drone's on-load battery to power it.

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