Battery management method for oil-electric hybrid UAV and oil-electric hybrid UAV

Abstract

The present invention relates to the technical field of battery management for hybrid electric drones, and in particular to a battery management method for hybrid electric drones and a hybrid electric drone. The battery management method, after the hybrid electric drone completes a flight mission, performs the following steps: detecting the current voltage of each battery pack in a rechargeable battery pack; determining the current minimum voltage of each battery pack in the rechargeable battery pack; screening out battery packs to be discharged from the rechargeable battery pack whose first difference between the current voltage and the current minimum voltage exceeds a first set threshold; and discharging the battery packs to be discharged so that the voltage of the battery packs to be discharged and the first difference do not exceed the first set threshold. The present invention discharges unbalanced battery packs after each flight mission is completed, ensuring that the battery packs are balanced when the hybrid electric drone performs a flight mission next time, thereby improving the power supply safety performance of the hybrid electric drone.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management for a hybrid electric unmanned aerial vehicle, and in particular to a battery management method for a hybrid electric unmanned aerial vehicle and a hybrid electric unmanned aerial vehicle. Background Art

[0002] Drones are widely used in the

[0003] Aerial photography, plant protection, express delivery, disaster relief, surveying and mapping, news reporting, power inspection, film and television shooting and many other fields. According to the different power supply methods, drones can be divided into battery-powered drones, fuel-powered drones and hybrid-powered drones. Battery-powered drones have short flight time and small load capacity, while fuel-powered drones are complex to control and have poor stability, making it difficult to meet the needs of industrial drones. Hybrid-powered drones have the dual advantages of large oil-powered load capacity and long flight time, and easy electric control and strong stability. They have developed rapidly and are widely used. They have been highly favored by domestic and foreign drone manufacturers and have been widely used in industrial surveying and mapping, agricultural plant protection and other fields.

[0004] A general hybrid system is equipped with a large-capacity lithium battery to cooperate with the internal combustion engine to share power output. However, due to its charging and discharging characteristics, the lithium battery has the characteristics of short life, easy overcharging and over-discharging, and high cost. In addition, the fuel of the oil-electric hybrid drone is gasoline, which is flammable. Once the battery catches fire, it is very easy to cause the aircraft to catch fire, causing huge economic losses, and even worse, affecting the safety of related practitioners.

[0005] How to improve the safety of power supply for hybrid UAVs is a technical problem that needs to be solved urgently. Summary of the invention

[0006] The purpose of the present invention is to provide a battery management method for a hybrid electric drone and a hybrid electric drone, so as to solve the problem that the power supply safety of the hybrid electric drone is not high.

[0007] The embodiment of the present invention provides the following solution:

[0008] In a first aspect, an embodiment of the present invention provides a battery management method for a hybrid UAV. After the hybrid UAV completes a flight mission, the following steps are performed:

[0009] Detect the current voltage of each battery pack in the rechargeable battery pack;

[0010] Determining the current minimum voltage of each battery pack in the rechargeable battery pack;

[0011] Screening out a battery pack to be discharged from the rechargeable battery pack, the battery pack having a first difference between the current voltage and the current lowest voltage exceeding a first set threshold;

[0012] The battery pack to be discharged is discharged so as to make the difference between the voltage of the battery pack to be discharged and the first value not exceed a first set threshold value.

[0013] In a possible embodiment, after the hybrid UAV completes the flight mission, the following steps are further performed:

[0014] When the first difference between the current voltage of any battery pack in the rechargeable battery group and the current minimum voltage does not exceed the first set threshold, the power supply of the hybrid drone is turned off.

[0015] In a possible embodiment, before the hybrid UAV takes off, the following steps are performed:

[0016] Detect the current voltage of each battery pack in the rechargeable battery pack;

[0017] determining a second difference between the current voltages of the battery packs;

[0018] If the second difference exceeds a second set threshold, the hybrid UAV is prohibited from taking off.

[0019] In a possible embodiment, after detecting the current voltage of each battery pack in the rechargeable battery pack, the method further includes:

[0020] Detect the current voltage of each battery pack in the rechargeable battery pack;

[0021] If the current voltage of any battery pack in the rechargeable battery group is greater than the set maximum charging voltage, or less than the set minimum discharging voltage, the hybrid drone is controlled to return.

[0022] In a possible embodiment, after the hybrid UAV takes off, the following steps are performed:

[0023] Detect the current temperature of the rechargeable battery pack;

[0024] If the current temperature of the rechargeable battery pack is greater than the set maximum temperature, the hybrid drone is controlled to return.

[0025] In a second aspect, an embodiment of the present invention provides a hybrid UAV, which applies the steps of the battery management method as described in any one of the first aspects above, including a power supply device, wherein the power supply device includes:

[0026] Internal combustion engine, generator, rectifier circuit, rechargeable battery pack and voltage equalization module;

[0027] The internal combustion engine is transmission-connected to the generator to drive the generator to operate;

[0028] The generator is connected to the rectifier circuit to output three-phase alternating current to the rectifier circuit;

[0029] The rectifier circuit is connected to the rechargeable battery pack to convert the three-phase alternating current into direct current and charge the rechargeable battery pack;

[0030] The voltage balancing module includes a control submodule and a plurality of controllable switches; the control submodule is connected to the control terminals of the plurality of controllable switches respectively to control the on and off of each controllable switch;

[0031] The rechargeable battery pack comprises a plurality of battery packs connected in series; wherein each battery pack is connected in series with an equalizing circuit; and the equalizing circuit comprises a discharge resistor connected in series with at least one controllable switch among the plurality of controllable switches.

[0032] In a possible embodiment, the balancing circuit is composed of a discharge resistor, a diode, and at least one controllable switch among the plurality of controllable switches connected in series.

[0033] In a possible embodiment, the voltage balancing module is an LTC6802-2 chip, and the SPI interface of the LTC6802-2 chip is used to communicate with the drone main controller.

[0034] In a possible embodiment, the voltage balancing module includes at least two LTC6802-2 chips; wherein the SPI interfaces of the LTC6802-2 chips are connected in parallel through a digital isolator to construct an SPI bus; and the SPI bus is used to communicate with the drone main controller.

[0035] In a possible embodiment, the control submodule is further connected to two ends of the battery pack to collect and monitor the voltage of the battery pack;

[0036] The control submodule is also connected to a platinum resistor, and the platinum resistor is fixed outside the rechargeable battery pack.

[0037] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0038] The present invention checks the voltage of each battery pack in the rechargeable battery group after each flight mission is completed, and discharges the battery pack whose voltage difference with the current lowest voltage exceeds a first set threshold, thereby ensuring that the voltage difference between each battery pack does not exceed the first set threshold when the hybrid UAV performs a flight mission next time, thereby improving the power supply safety performance of the hybrid UAV.

[0039] Furthermore, the present invention also provides a hybrid electric drone, in which a battery pack discharge circuit is constructed by connecting a controllable switch in a voltage balancing module in series with a discharge resistor and a battery pack, and the control submodule in the voltage balancing module controls the on and off of the controllable switch to achieve discharge of the battery pack, thereby ensuring the voltage balance of the battery pack in the rechargeable battery pack, avoiding trickle current and burning risks caused by voltage imbalance between battery packs in the rechargeable battery pack, and ultimately improving the power supply safety of the hybrid electric drone.

[0040] Furthermore, the present invention fixes the flow direction of the current through the diode, so that the battery pack can discharge normally, but cannot receive reverse current from other high-voltage battery packs, thereby protecting the battery pack and further improving the safety of the power supply of the hybrid drone.

[0041] Furthermore, the present invention adopts the LTC6802-2 chip as a voltage balancing module, which facilitates real-time monitoring of the voltage of each battery pack and timely discharges some battery packs with higher voltages to quickly and accurately achieve voltage balance in the rechargeable battery pack, further improving the safety of power supply for the hybrid drone.

[0042] Furthermore, the present invention uses multiple LTC6802-2 chips as voltage balancing modules, so that the maximum number of battery packs connected in series in the rechargeable battery pack is no longer limited by the number of 12 battery packs that can be connected to a single LTC6802-2 chip, thereby improving the applicability of power supply for hybrid drones. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 is a flow chart of a possible battery management method embodiment for a hybrid electric drone provided by an embodiment of the present invention;

[0045] Figure 2 is a structural schematic diagram of a power supply device in a possible oil-electric hybrid UAV embodiment provided by an embodiment of the present invention;

[0046] Figure 3 is a schematic structural diagram of a possible power supply device for a hybrid UAV provided in an embodiment of the present invention;

[0047] Figure 4It is a connection diagram of the peripheral circuit of an LTC6802-2 chip provided by an embodiment of the present invention.

[0048] Figure 5 The invention provides a connection diagram of a voltage balancing module including three LTC6802-2 chips. DETAILED DESCRIPTION

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the embodiments of the present invention.

[0050] See also Figure 1 , Figure 1 A flow chart of a battery management method for a hybrid electric drone provided in an embodiment of the present invention.

[0051] In an embodiment of the present invention, the hybrid UAV uses a voltage balancing module to obtain the voltage of each battery pack in the battery group; the voltage balancing module is communicatively connected to the main controller of the hybrid UAV, and can send the measured voltage of each battery pack to the main controller; the main controller of the hybrid UAV is also controlled and connected to the flight control system, and can control the hybrid UAV to take off, return, etc.

[0052] After the hybrid drone completes its flight mission, that is, completes the return operation and stops on the ground, perform the following steps:

[0053] Step 101, detecting the current voltage of each battery pack in the rechargeable battery pack.

[0054] Specifically, the voltages at the positive and negative poles of each battery pack in the rechargeable battery pack can be collected, and then through analog-to-digital conversion, the numerical values ​​representing the current voltage of each battery pack can be obtained based on the numerical values ​​representing the voltages at the positive and negative poles of each battery pack. The main controller of the hybrid drone stores these numerical values ​​representing the current voltage of each battery pack in a register, thereby realizing the detection of the current voltage of each battery pack.

[0055] Step 102, determining the current lowest voltage of each battery pack in the rechargeable battery pack.

[0056] Specifically, after the main controller obtains the current voltage of each battery pack in the rechargeable battery pack, it can determine the current lowest voltage of each battery pack in the rechargeable battery pack by sorting the current voltages of each battery pack stored in the register. The main controller stores the value representing the current lowest voltage in a register for easy retrieval and comparison later.

[0057] Step 103 , selecting from the rechargeable battery packs a battery pack to be discharged whose first difference between the current voltage and the current lowest voltage exceeds a first set threshold.

[0058] Specifically, by comparing the current voltage of each battery pack stored in the register with the current minimum voltage one by one, the difference between the current voltage of each battery pack and the current minimum voltage is obtained, and the battery packs with a difference exceeding 0.1V are found. These battery packs will undergo subsequent discharge operations.

[0059] Step 104 , discharging the battery pack to be discharged so that the difference between the voltage of the battery pack to be discharged and the first value does not exceed a first set threshold.

[0060] Specifically, after the battery packs that need to be discharged are screened out, these battery packs are discharged through discharge resistors or other energy-consuming elements so that the difference between the voltage of these battery packs after discharge and the current minimum voltage is within 0.1V.

[0061] The embodiment of the present invention checks the voltage of each battery pack in the rechargeable battery group after each flight mission is completed, and discharges the battery pack whose voltage difference with the current lowest voltage exceeds the first set threshold, thereby ensuring that the voltage difference between each battery pack does not exceed the first set threshold when the hybrid UAV performs a flight mission next time, thereby improving the power supply safety performance of the hybrid UAV.

[0062] In a possible embodiment, after the hybrid UAV completes the flight mission, the following steps are further performed:

[0063] When the first difference between the current voltage of any battery pack in the rechargeable battery group and the current minimum voltage does not exceed the first set threshold, the power supply of the hybrid drone is turned off.

[0064] Specifically, after the hybrid UAV completes its flight mission, the voltage of each battery pack is collected and measured. If the difference between the voltage of each battery pack and the current minimum voltage does not exceed 0.1V, the main controller issues a command to shut down the power of the hybrid UAV.

[0065] In a possible embodiment, before the hybrid UAV takes off, the following steps are performed:

[0066] Step 105, detecting the current voltage of each battery pack in the rechargeable battery pack.

[0067] Specifically, the voltages at the positive and negative poles of each battery pack in the rechargeable battery pack can be collected, and then through analog-to-digital conversion, the numerical values ​​representing the current voltage of each battery pack can be obtained based on the numerical values ​​representing the voltages at the positive and negative poles of each battery pack. The main controller of the hybrid drone stores these numerical values ​​representing the current voltage of each battery pack in a register, thereby realizing the detection of the current voltage of each battery pack.

[0068] Step 106 , determining a second difference between the current voltages of the battery packs.

[0069] Specifically, the main controller may perform a pairwise difference between the numerical values ​​representing the current voltages of the battery packs stored in the registers to obtain a second difference between the current voltages of the battery packs.

[0070] Step 107: If the second difference exceeds a second set threshold, the hybrid UAV is prohibited from taking off.

[0071] Specifically, if the second difference value obtained in step 106 exceeds 0.1V, it means that the voltage difference between two battery packs in the current battery pack is too large, the voltage is unbalanced, and there is a power supply risk. At this time, the main controller issues a command to prohibit the hybrid drone from taking off and sends an alarm to the user.

[0072] In a possible embodiment, after detecting the current voltage of each battery pack in the rechargeable battery pack, the method further includes:

[0073] Step 108, detecting the current voltage of each battery pack in the rechargeable battery pack.

[0074] Specifically, the voltages at the positive and negative poles of each battery pack in the rechargeable battery pack can be collected, and then through analog-to-digital conversion, the numerical values ​​representing the current voltage of each battery pack can be obtained based on the numerical values ​​representing the voltages at the positive and negative poles of each battery pack. The main controller of the hybrid drone stores these numerical values ​​representing the current voltage of each battery pack in a register, thereby realizing the detection of the current voltage of each battery pack.

[0075] Step 109: If the current voltage of any battery pack in the rechargeable battery group is greater than the set maximum charging voltage, or less than the set minimum discharging voltage, the hybrid drone is controlled to return.

[0076] Specifically, since the hybrid UAV continues to charge the rechargeable battery pack by burning oil when performing flight missions, during this process, the rechargeable battery pack may be overcharged. At the same time, the rechargeable battery pack continues to discharge and may be over-discharged. Therefore, the embodiment of the present invention monitors the current voltage of the battery pack in real time. When the current voltage of any battery pack is greater than the set maximum charging voltage, it is determined that the rechargeable battery pack is overcharged. At this time, the main controller issues a command to control the UAV to return. When the current voltage of any battery pack is less than the set minimum discharge voltage, it is determined that the rechargeable battery pack is over-discharged. At this time, the main controller issues a command to control the UAV to return. In this way, the occurrence of battery combustion, crash, etc. in the UAV is avoided, and the power supply safety performance of the UAV is improved.

[0077] In a possible embodiment, after the hybrid UAV takes off, the following steps are performed:

[0078] Step 110, detecting the current temperature of the rechargeable battery pack.

[0079] Specifically, the voltages at the positive and negative poles of each battery pack in the rechargeable battery pack can be collected, and then through analog-to-digital conversion, a value representing the current voltage of each battery pack can be obtained based on the value representing the voltage at the positive and negative poles of each battery pack. The main controller of the hybrid drone stores these values ​​representing the current voltage of each battery pack in a register, thereby realizing the detection of the current voltage of each battery pack.

[0080] Step 111: If the current temperature of the rechargeable battery pack is greater than the set maximum temperature, the hybrid drone is controlled to return.

[0081] Specifically, a thermistor such as a platinum resistor can be set outside the rechargeable battery pack. The resistance of the thermistor changes with the temperature of the rechargeable battery pack. By detecting the resistance of the thermistor in real time, the current temperature of the rechargeable battery pack can be obtained. In the embodiment of the present invention, when the current temperature of the rechargeable battery pack is greater than the set maximum temperature, the safety performance of the battery pack is determined to be low. At this time, the main controller issues a command to control the drone to return.

[0082] See also Figure 2 , Figure 2 A schematic diagram of the structure of a power supply device in a possible hybrid UAV embodiment provided by an embodiment of the present invention. The power supply device is used to supply power to various components on the UAV, and specifically includes: an internal combustion engine 21, a generator 22, a rectifier circuit 23, a rechargeable battery pack 24 and a voltage equalization module 5.

[0083] The internal combustion engine 21 is transmission-connected to the generator 22 to drive the generator 22 to operate.

[0084] Specifically, the internal combustion engine 21 converts the chemical energy of the fuel into mechanical energy to drive the generator 22. The specific internal combustion engine 21 can be a small diesel engine, and use aviation diesel as fuel. This solution has high energy conversion efficiency and little pollution to the environment.

[0085] Specifically, the internal combustion engine 21 can be connected to the rotor of the generator 2 through a crank, and the other end of the crank is connected to the piston in the combustion chamber of the internal combustion engine 21. In this way, when the internal combustion engine 21 drives the piston to move up and down through the combustion of fuel, the crank drives the rotor of the generator 22 to rotate, thereby realizing the transmission connection between the internal combustion engine 21 and the generator 22.

[0086] The generator 22 is connected to the rectifier circuit 23 to output three-phase alternating current to the rectifier circuit 23 .

[0087] Specifically, the generator 22 drives the generator rotor to rotate with the mechanical energy generated by the internal combustion engine 21 to generate three-phase alternating current through changes in the magnetic field inside the generator, and then outputs the three-phase alternating current through the U, V, and W three-phase output terminals on the stator side. Specifically, the generator 22 can be a magnetic AC generator.

[0088] The rectifier circuit 23 is connected to the rechargeable battery pack 24 to convert the three-phase AC power into DC power and charge the rechargeable battery pack 24 .

[0089] Specifically, the rectifier circuit 23 can convert the input AC power into DC power for use by the rechargeable battery pack 4. Specifically, a three-phase full-bridge rectifier circuit can be used as the rectifier circuit 3, or thyristors, IGBTs and other controllable switching components can be used in conjunction with PWM signal control to achieve conversion from AC power to DC power.

[0090] The voltage balancing module 25 includes a control submodule and a plurality of controllable switches; the control submodule is connected to the control terminals of the plurality of controllable switches respectively to control the on and off of each controllable switch.

[0091] Specifically, the control submodule and the control ends of the controllable switches are in a one-to-many connection relationship. The control submodule is provided with a plurality of output terminals. The control end of each controllable switch is connected to an output terminal, and the control submodule controls the on and off of each controllable switch through the output terminal.

[0092] The rechargeable battery pack 24 includes a plurality of battery packs connected in series, wherein each battery pack is connected in series with a balancing circuit; and the balancing circuit is composed of a discharge resistor connected in series with at least one controllable switch among the plurality of controllable switches.

[0093] Specifically, in the embodiment of the present invention, each battery pack is configured with a balancing circuit, and each battery pack is connected in series with its corresponding balancing circuit; each balancing circuit includes at least one controllable switch in the voltage balancing module 25, and this controllable switch (or these controllable switches) is connected in series with the discharge resistor to form the balancing circuit. Of course, the controllable switches included in the balancing circuit corresponding to each battery pack are different.

[0094] Specifically, the control submodule in the voltage balancing module 25 can control the on and off of the controllable switch. When the controllable switch is turned on, the discharge resistor is connected in series with the battery pack to release the excess electrical energy of the battery pack.

[0095] Specifically, the embodiment of the present invention can release all the electric energy of all batteries before each charging to achieve voltage balancing management of all battery packs in the rechargeable battery pack.

[0096] Specifically, the controllable switch can use controllable switch components such as thyristors and IGBTs, and the control submodule can use ST's M32 series microcontroller to control the controllable switch.

[0097] The embodiment of the present invention constructs a battery pack discharge circuit by connecting the controllable switch in the voltage balancing module in series with the discharge resistor and the battery pack, and controls the on and off of the controllable switch through the control submodule in the voltage balancing module to achieve the discharge of the battery pack, thereby ensuring the voltage balance of the battery pack in the rechargeable battery pack, avoiding the trickle current and burning risk caused by the voltage imbalance between the battery packs in the rechargeable battery pack, and finally improving the power supply safety of the hybrid UAV.

[0098] In a possible embodiment, the balancing circuit is composed of a discharge resistor, a diode, and at least one controllable switch among the plurality of controllable switches connected in series.

[0099] Specifically, the connection of the diode must ensure that the current flow direction of the diode is from the positive electrode of the battery pack to the negative electrode of the battery pack.

[0100] The embodiment of the present invention fixes the flow direction of the current through the diode, so that the battery pack can discharge normally, but cannot receive reverse current from other high-voltage battery packs, thereby protecting the battery pack and further improving the safety of the power supply of the hybrid drone.

[0101] In a possible embodiment, the control submodule is further connected to two ends of the battery pack to collect and monitor the voltage of the battery pack.

[0102] Specifically, the two ends of the battery pack are connected to the control submodule, and the voltage signals at both ends of the battery pack can be digitized through an analog-to-digital converter, so that the control submodule can know the voltage at both ends of the battery pack, so as to control the on and off of the control switch more flexibly and accurately.

[0103] In a possible embodiment, the control submodule is further connected to a platinum resistor, and the platinum resistor is fixed on the outside of the battery pack.

[0104] Specifically, the platinum resistor is a thermistor, and the curve of its resistance and temperature change is linear within a certain temperature range. In the embodiment of the present invention, the platinum resistor is placed close to the outside of the battery pack to detect the temperature of the battery pack in real time to prevent the battery pack from exploding due to overheating.

[0105] In a possible embodiment, the rectifier circuit is a three-phase full-bridge rectifier circuit.

[0106] Specifically, in order to better illustrate the embodiment of the present invention, the embodiment of the present invention further provides a power supply device for a hybrid UAV.

[0107] See also Figure 3 , Figure 3 FIG. 1 is a schematic diagram of a power supply device for a hybrid UAV provided by an embodiment of the present invention.

[0108] Specifically, a diesel internal combustion engine is used as the internal combustion engine 21, and a magneto alternator is used as the generator 22. The internal combustion engine 21 is connected to the rotor of the generator 22 via a crank, and the other end of the crank is connected to the piston in the combustion chamber of the internal combustion engine 1, so that when the internal combustion engine 21 drives the piston to move up and down through the combustion of fuel, the crank drives the rotor of the generator 22 to rotate, thereby realizing the transmission connection between the internal combustion engine 21 and the generator 22.

[0109] Specifically, a three-phase full-bridge rectifier circuit is used as the rectifier circuit 23, one end of the rectifier circuit 23 is connected to the U, V, and W three-phase output terminals on the stator side of the generator 22, and the other end is connected to the rechargeable battery pack 24, for converting three-phase alternating current into direct current for charging the rechargeable battery pack 24.

[0110] Specifically, the rechargeable battery group 24 is composed of three battery packs (E1, E2, E3) connected in series.

[0111] Specifically, the voltage balancing module 25 includes six IO interfaces (J1, J2, J3, J4, J5, and J6); in the voltage balancing module 25, a controllable switch S1 is connected between the interface J1 and the interface J2, a controllable switch S2 is connected between the interface J3 and the interface J4, and a controllable switch S3 is connected between the interface J5 and the interface J6. The controllable switches S1, S2, and S3 all use JFET junction field effect transistors; the voltage balancing module 5 is also provided with an MCU, which is connected to the gate control terminals of the controllable switches S1, S2, and S3 respectively to control The on and off of controllable switches S1, S2, and S3; the voltage balancing module 5 is connected to the positive electrode of the battery pack E1 through the interface J1, and is connected to the negative electrode of the battery pack E1 through the interface J2, the diode D1, and the discharge resistor R1; the voltage balancing module 5 is connected to the positive electrode of the battery pack E2 through the interface J3, and is connected to the negative electrode of the battery pack E2 through the interface J4, the diode D2, and the discharge resistor R2; the voltage balancing module 25 is connected to the positive electrode of the battery pack E3 through the interface J5, and is connected to the negative electrode of the battery pack E3 through the interface J6, the diode D3, and the discharge resistor R3.

[0112] In a possible embodiment, the voltage balancing module is an LTC6802-2 chip, and the SPI interface of the LTC6802-2 chip is used to communicate with the drone main controller.

[0113] For details, please refer to Figure 3 , Figure 3 The figure shows the connection diagram of the peripheral circuit of the LTC6802-2 chip. The charging battery pack includes 12 battery packs connected in series, the negative electrode of the first battery pack is connected to the 26th pin GND of the LTC6802-2 chip, and its positive electrode is connected to the 24th pin V1, the negative electrode of the second battery pack is connected to the 24th pin V1 of the LTC6802-2 chip, and its positive electrode is connected to the 22nd pin V2 of the LTC6802-2 chip, the negative electrode of the third battery pack is connected to the 22nd pin V2 of the LTC6802-2 chip, and its positive electrode is connected to the 20th pin V3 of the LTC6802-2 chip, and so on, the negative electrode of the 12th battery pack is connected to the 4th pin V11 of the LTC6802-2 chip, and its positive electrode is connected to the 2nd pin V12 of the LTC6802-2 chip, so that each battery pack is connected to the battery input pin of the LTC6802-2 chip in turn. A discharge resistor R1X is connected between the 2nd and 3rd pins of the LTC6802-2 chip, a discharge resistor R2X is connected between the 4th and 5th pins of the LTC6802-2 chip, and so on. A discharge resistor R12X is connected between the 24th and 25th pins of the LTC6802-2 chip.

[0114] Inside the LTC6802-2 chip, a controllable switch is provided between its 3rd and 4th pins to discharge the 12th battery pack through the discharge resistor R1X, and a controllable switch is provided between its 5th and 6th pins to discharge the 11th battery pack through the discharge resistor R2X. And so on, a controllable switch is provided between its 25th and 26th pins to discharge the 1st battery pack through the discharge resistor R12X.

[0115] There are two temperature acquisition channels on the LTC6802-2 chip, namely pin 28 and pin 29, which can be connected to thermistors to collect battery temperature.

[0116] The LTC6802-2 chip communicates with the drone main controller through its SPI interface. The drone main controller can use this to send a write configuration register command to configure the LTC6802-2 chip, then turn on the battery pack voltage AD conversion register, and finally send a read battery pack voltage register command to read the voltage of each battery pack.

[0117] The embodiment of the present invention adopts the LTC6802-2 chip as a voltage balancing module, which is convenient for real-time monitoring of the voltage of each battery pack and timely discharging of some battery packs with higher voltages, so as to quickly and accurately achieve voltage balance in the rechargeable battery pack, further improving the power supply safety of the hybrid drone.

[0118] In a possible embodiment, the voltage balancing module includes at least two LTC6802-2 chips; wherein the SPI interfaces of the LTC6802-2 chips are connected in parallel through a digital isolator to construct an SPI bus; and the SPI bus is used to communicate with the drone main controller.

[0119] For details, please refer to Figure 4 , Figure 4 The figure shows the connection diagram of the voltage balancing module including three LTC6802-2 chips. The SPI interfaces of each LTC6802-2 chip are connected in parallel through a digital isolator to build an SPI bus; the SPI bus is used to communicate with the drone main controller to enable the drone main controller to collect voltage data of 36 battery packs.

[0120] The embodiment of the present invention adopts multiple LTC6802-2 chips as voltage balancing modules, so that the maximum number of battery packs connected in series of the rechargeable battery pack is no longer limited by the number of 12 battery packs that can be connected to a single LTC6802-2 chip, thereby improving the applicability of power supply for hybrid drones.

[0121] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0122] The embodiment of the present invention checks the voltage of each battery pack in the rechargeable battery group after each flight mission is completed, and discharges the battery pack whose voltage difference with the current lowest voltage exceeds the first set threshold, thereby ensuring that the voltage difference between each battery pack does not exceed the first set threshold when the hybrid UAV performs a flight mission next time, thereby improving the power supply safety performance of the hybrid UAV.

[0123] Furthermore, an embodiment of the present invention also provides a hybrid UAV, in which a battery pack discharge circuit is constructed by connecting a controllable switch in a voltage balancing module in series with a discharge resistor and a battery pack, and the control submodule in the voltage balancing module controls the on and off of the controllable switch to discharge the battery pack, thereby ensuring the voltage balance of the battery packs in the rechargeable battery pack, avoiding the risk of trickle current and burning caused by voltage imbalance between the battery packs in the rechargeable battery pack, and finally Improved The safety of power supply for hybrid drones.

[0124] Furthermore, the embodiment of the present invention fixes the flow direction of the current through the diode, so that the battery pack can discharge normally, but cannot receive reverse current from other high-voltage battery packs, thereby protecting the battery pack and further improving the safety of the power supply of the hybrid drone.

[0125] Furthermore, the embodiment of the present invention adopts the LTC6802-2 chip as a voltage balancing module, which facilitates real-time monitoring of the voltage of each battery pack and timely discharges some battery packs with higher voltages to quickly and accurately achieve voltage balance in the rechargeable battery pack, further improving the safety of power supply for the hybrid drone.

[0126] Furthermore, the embodiment of the present invention uses multiple LTC6802-2 chips as voltage balancing modules, so that the maximum number of battery packs connected in series in the rechargeable battery pack is no longer limited by the number of 12 battery packs that can be connected to a single LTC6802-2 chip, thereby improving the applicability of power supply for hybrid drones.

[0127] The specific embodiments of the present invention described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0128] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

Claims

1. A battery management method for a hybrid UAV, characterized in that: After the hybrid drone completes its flight mission, perform the following steps: Detect the current voltage of each battery pack in the rechargeable battery pack; Determining the current minimum voltage of each battery pack in the rechargeable battery pack; Screening out a battery pack to be discharged from the rechargeable battery pack, the battery pack having a first difference between the current voltage and the current lowest voltage exceeding a first set threshold; Discharging the battery pack to be discharged so that a first difference between the voltage of the battery pack to be discharged and the current lowest voltage does not exceed a first set threshold; Before the hybrid drone takes off, perform the following steps: Detect the current voltage of each battery pack in the rechargeable battery pack; determining a second difference between the current voltages of the battery packs; If the second difference exceeds a second set threshold, the hybrid UAV is prohibited from taking off.

2. The battery management method according to claim 1, characterized in that: After the hybrid drone completes its flight mission, the following steps are performed: When the first difference between the current voltage of any battery pack in the rechargeable battery group and the current minimum voltage does not exceed the first set threshold, the power supply of the hybrid drone is turned off.

3. The battery management method according to claim 1, characterized in that: After detecting the current voltage of each battery pack in the rechargeable battery pack, the method further includes: Detect the current voltage of each battery pack in the rechargeable battery pack; If the current voltage of any battery pack in the rechargeable battery group is greater than the set maximum charging voltage, or less than the set minimum discharging voltage, the hybrid drone is controlled to return.

4. The battery management method according to claim 1, characterized in that: After the hybrid drone takes off, perform the following steps: Detect the current temperature of the rechargeable battery pack; If the current temperature of the rechargeable battery pack is greater than the set maximum temperature, the hybrid drone is controlled to return.

5. A hybrid UAV using the battery management method according to any one of claims 1 to 4, comprising a power supply device, characterized in that: The power supply device comprises: Internal combustion engine, generator, rectifier circuit, rechargeable battery pack and voltage equalization module; The internal combustion engine is transmission-connected to the generator to drive the generator to operate; The generator is connected to the rectifier circuit to output three-phase alternating current to the rectifier circuit; The rectifier circuit is connected to the rechargeable battery pack to convert the three-phase alternating current into direct current and charge the rechargeable battery pack; The voltage balancing module includes a control submodule and a plurality of controllable switches; the control submodule is connected to the control terminals of the plurality of controllable switches respectively to control the on and off of each controllable switch; The rechargeable battery pack comprises a plurality of battery packs connected in series; wherein each battery pack is connected in series with an equalizing circuit; and the equalizing circuit comprises a discharge resistor connected in series with at least one controllable switch among the plurality of controllable switches.

6. The hybrid UAV according to claim 5, characterized in that: The balancing circuit is composed of a discharge resistor, a diode and at least one controllable switch among the plurality of controllable switches connected in series.

7. The hybrid UAV according to claim 5, characterized in that: The voltage balancing module is an LTC6802-2 chip, and the SPI interface of the LTC6802-2 chip is used for communication connection with the main controller of the hybrid UAV.

8. The hybrid UAV according to claim 7, characterized in that: The voltage balancing module includes at least two LTC6802-2 chips; wherein the SPI interfaces of the LTC6802-2 chips are connected in parallel through a digital isolator to construct an SPI bus; and the SPI bus is used to communicate with the main controller of the hybrid UAV.

9. The hybrid UAV according to claim 5, characterized in that: The control submodule is also connected to both ends of the battery pack to collect and monitor the voltage of the battery pack; The control submodule is also connected to a platinum resistor, and the platinum resistor is fixed outside the rechargeable battery pack.

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