CN114211991B

CN114211991B - Control unit for wireless charging unmanned aerial vehicle, unmanned aerial vehicle and control method

Info

Publication number: CN114211991B
Application number: CN202111561316.4A
Authority: CN
Inventors: 郑加明; 薛松柏; 徐大勇; 胥锋; 杨邑
Original assignee: Sichuan AOSSCI Technology Co Ltd
Current assignee: Sichuan AOSSCI Technology Co Ltd
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2023-08-04
Anticipated expiration: 2041-12-15
Also published as: CN114211991A

Abstract

The invention provides a control unit for a wireless charging unmanned aerial vehicle, the unmanned aerial vehicle and a control method, and belongs to the technical field of unmanned aerial vehicle control. The control unit includes: the power-on pre-charging control circuit comprises a power supply branch circuit arranged between the output end of a power supply and a distribution box and a pre-charging branch circuit connected in parallel with the power supply branch circuit, wherein the pre-charging branch circuit is provided with a first resistor and a first switching element which are connected in series, the first switching element is provided with a first control end so as to control the power supply to pre-charge the distribution box by controlling the first control end, and the power supply branch circuit is provided with a second switching element with a second control end; the self-locking unit is provided with at least one delay circuit connected with the second control end in series, each delay circuit is powered by the distribution box, and the self-locking unit is used for controlling the second switching element to be closed after the distribution box is electrified and the delay circuit delays for a preset time so as to conduct the power supply branch. The control unit can realize reliable self-locking of the power-on state.

Description

Control unit for wireless charging unmanned aerial vehicle, unmanned aerial vehicle and control method

Technical Field

The invention belongs to the technical field of unmanned aerial vehicle control, and particularly relates to a control unit for a wireless charging unmanned aerial vehicle, the unmanned aerial vehicle and a control method.

Background

Due to battery technology level limitations, endurance is the biggest technical challenge faced by current drones. And the development and popularization of the wireless charging technology can reduce the dependence of the unmanned aerial vehicle on a standby battery or a charging cable, prolong the endurance time and the maximum range of the unmanned aerial vehicle, and provide a guarantee for the unmanned aerial vehicle to smoothly finish tasks.

The wireless charging is characterized in that the wireless charging can be controlled remotely, the whole process of landing, charging and taking off of the unmanned aerial vehicle can be realized independently, no intervention and assistance are needed on site, and the traditional scheme of controlling the power on and off of the system through a hardware switch and a pluggable battery connector is not feasible. Therefore, a technical scheme capable of remotely realizing power-on and power-off control with high reliability is urgently provided.

Disclosure of Invention

An object of the first aspect of the present invention is to provide a control unit for a wireless charging drone, capable of achieving reliable self-locking of the powered-on state.

It is a further object of the invention to improve the service life of the component parts.

Another object of the invention is to ensure the reliability of the power-on self-locking function.

An object of the second aspect of the invention is to provide a drone comprising the control unit described above.

An object of the third aspect of the present invention is to provide a control method for the above-mentioned control unit.

In particular, the present invention provides a control unit for a wireless charging unmanned aerial vehicle, comprising:

the power-on pre-charging control circuit comprises a power supply branch circuit arranged between the output end of a power supply and a distribution box and a pre-charging branch circuit connected in parallel with the power supply branch circuit, wherein a first resistor and a first switching element which are connected in series are arranged on the pre-charging branch circuit, the first switching element is provided with a first control end so as to control the power supply to pre-charge the distribution box by controlling the first control end, and a second switching element with a second control end is arranged on the power supply branch circuit;

the self-locking unit is provided with at least one delay circuit connected with the second control end in series, each delay circuit is powered by the distribution box, and the self-locking unit is used for controlling the second switching element to be closed after the distribution box is electrified and the delay circuit delays for a preset time so as to conduct the power supply branch.

Optionally, the self-locking unit includes two parallel first delay circuits and second delay circuits with different types, and the first delay circuits and the second delay circuits can both delay the preset time.

Optionally, the control unit further comprises:

and the power-down control circuit comprises a power-down branch connected with the second control end, and a third switching element with a third control end is arranged on the power-down branch so as to control the disconnection of the power supply branch by controlling the third control end.

Optionally, the control unit further comprises:

the power-down locking control circuit comprises a fourth switching element which is arranged on the power-down branch and provided with a fourth control end, so that the power-down branch is controlled to be disconnected and the power supply branch is controlled to be always connected by controlling the fourth control end.

Optionally, the first switch element is a pre-charging relay, one end of a coil of the pre-charging relay is connected in series with a second resistor, the other end of the coil of the pre-charging relay is connected with the wireless charging module, one end of the second resistor, which is far away from the coil of the pre-charging relay, is connected with the output end of the power supply, and the coil of the pre-charging relay is also connected with the first freewheeling diode in parallel.

Optionally, the second switch element is a power relay, the coil of the power relay is connected in parallel with the second freewheeling diode, the first delay circuit comprises a first diode, a resistance-capacitance delay circuit and a third resistor which are sequentially connected in series, the second delay circuit comprises a second diode, a digital delay circuit and a fourth resistor which are sequentially connected in series, the first delay circuit is provided with one end of the first diode and one end of the second delay circuit is connected with the distribution box, and the first delay circuit is provided with one end of the third resistor and one end of the fourth resistor is connected with the coil of the power relay.

Optionally, the third switching element is a power-down control relay, one end of a coil of the power-down control relay is connected with the output end of the power supply after being connected with the fifth resistor in series, the other end of the coil of the power-down control relay is connected with the wireless charging module, and the coil of the power-down control relay is also connected with the third freewheeling diode in parallel.

Optionally, the fourth switching element is a lower electric locking relay, one end of a coil of the lower electric locking relay is connected with the flight management unit, the other end of the coil of the lower electric locking relay is grounded, and the coil of the lower electric locking relay is also connected with the fourth freewheel diode in parallel.

Optionally, the power-down locking relay is a normally closed relay.

In particular, the invention also provides a unmanned aerial vehicle comprising the control unit according to any one of the above.

In particular, the present invention also provides a control method for the control unit of any one of the above, the control method comprising:

receiving a battery charging instruction and charging a battery of the wireless charging module according to the battery charging instruction;

after the battery of the wireless charging module is charged, controlling the pre-charging branch to be conducted according to a pre-charging control instruction;

after the pre-charging branch is conducted, the self-locking unit works so as to conduct the power supply branch after the distribution box is electrified for a preset time.

According to the embodiment of the invention, the first switching element with the control end is arranged, so that the remote control of the precharge can be realized, and the power-on self-locking can be realized through the design of the distribution box and the delay circuit, thereby ensuring the reliability of the power-on state. The service life of the parts can be prolonged by arranging the pre-charging loop.

Furthermore, when the self-locking unit comprises a plurality of delay circuits, a redundant design is provided for power-on self-locking, so that the reliability of the power-on self-locking can be further improved, namely the reliability of the system is realized.

According to one embodiment of the invention, the self-locking unit comprises two first delay circuits and second delay circuits which are connected in parallel and have different types, and the two delay circuits are different in failure reason, so that when one failure reason occurs to the circuits, the other delay circuit can still normally operate to ensure the power-on self-locking function.

According to one embodiment of the invention, the normally closed contact of the power-down locking relay and the normally open contact of the power-down locking relay form a power-down branch, a power-down locking signal is provided for the power-down locking relay through the flight management unit, so that the normally closed contact of the power-down locking relay is disconnected, a power-down locking state is formed at the moment, and even if the contact of the power-down locking relay is closed, the power cannot be turned off. The unmanned aerial vehicle is automatically allowed to be powered down only after falling under any condition, so that reliable power-down locking is realized.

The above, as well as additional objectives, advantages, and features of the present invention will become apparent to those skilled in the art from the following detailed description of a specific embodiment of the present invention when read in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the invention will be described in detail hereinafter by way of example and not by way of limitation with reference to the accompanying drawings. The same reference numbers will be used throughout the drawings to refer to the same or like parts or portions. It will be appreciated by those skilled in the art that the drawings are not necessarily drawn to scale. In the accompanying drawings:

fig. 1 is a connection block diagram of a control unit for a wireless charging drone according to one embodiment of the present invention;

fig. 2 is a schematic diagram of a control unit for a wireless charging drone according to one embodiment of the present invention;

FIG. 3 is a schematic diagram of a power interface for a control unit of a wireless charging drone according to one embodiment of the present invention;

FIG. 4 is a schematic diagram of a control interface for a control unit of a wireless charging drone according to one embodiment of the present invention;

FIG. 5 is a schematic diagram of a power-on pre-charge control circuit for a control unit of a wireless charging drone, according to one embodiment of the present invention;

fig. 6 is a schematic diagram of a power down control circuit and a power down lock control circuit for a control unit of a wireless charging drone according to one embodiment of the present invention;

FIG. 7 is a schematic diagram of a resistance-capacitance delay circuit for a control unit of a wireless charging drone, according to one embodiment of the present invention;

FIG. 8 is a schematic diagram of a digital delay circuit for a control unit of a wireless charging drone according to one embodiment of the present invention;

fig. 9 is a schematic diagram of an internal buck regulator circuit for a control unit of a wireless charging drone according to one embodiment of the present invention;

fig. 10 is a flowchart of a control method according to an embodiment of the present invention.

Reference numerals:

100-power supply, 200-distribution box, 11-first resistor, 20-first switching element, 201-first control terminal, 30-second switching element, 301-second control terminal, 40-delay circuit, 21-precharge relay, 12-second resistor, 71-first freewheeling diode, 31-power relay, 72-second freewheeling diode, 81-first diode, 41-resistor Rong Yanshi circuit, 13-third resistor, 82-second diode, 42-digital delay circuit, 14-fourth resistor, 51-power-down control relay, 15-fifth resistor, 73-third freewheeling diode, 61-power-down lockout relay, 74-fourth freewheeling diode

Detailed Description

Fig. 1 is a connection block diagram of a control unit for a wireless charging drone according to one embodiment of the present invention. Fig. 2 is a schematic diagram of a control unit for a wireless charging drone according to one embodiment of the present invention. LOCK in fig. 2 is a control signal for power-down locking, ON is a power-up control signal, and OFF is a power-down control signal. As shown in fig. 1, in one embodiment, the control unit for a wireless charging unmanned aerial vehicle of the present invention includes a power-on precharge control circuit and a self-locking unit. The power-on pre-charge control circuit comprises a power supply branch circuit arranged between the output end of the power supply 100 and the distribution box 200, and a pre-charge branch circuit connected in parallel with the power supply branch circuit, wherein a first resistor 11 and a first switching element 20 are arranged on the pre-charge branch circuit, the first switching element 20 is provided with a first control end 201, and the power supply 100 is controlled to pre-charge the distribution box 200 by controlling the first control end 201. That is, after controlling the first switching element 20 to be closed, the precharge branch is communicated, and the power supply 100 precharges the distribution box 200. Optionally, the first resistor 11 is a high-energy resistor, and is used for raising the voltage of the circuit at the subsequent stage to a preset voltage within a specified time, that is, after the pre-charging branch is connected, the power distribution box 200 at the subsequent stage of the first resistor 11 can be raised to the preset voltage within the specified time, and the preset voltage can be 90% -99% of the power supply voltage, where the power supply 100 is a battery. As shown in fig. 2, in one embodiment, the first switching element 20 is a pre-charging relay 21, one end of a coil of the pre-charging relay 21 is connected in series with the second resistor 12, the other end is connected to the wireless charging module, one end of the second resistor 12 away from the coil of the pre-charging relay 21 is connected to the output end of the power supply 100, and the coil of the pre-charging relay 21 is further connected in parallel with the first freewheeling diode 71. The second resistor 12 is divided by the coil resistor of the precharge relay 21 so that the coil resistor operates in the rated voltage range. The ground-on signal is provided by the wireless charging module, the contact of the pre-charging relay 21 is controlled to be closed, the pre-charging is performed by the second resistor 12, the distribution box 200 is electrified, and a secondary power supply is provided for the following self-locking unit.

A second switching element 30 having a second control terminal 301 is provided on the power supply branch. The self-locking unit is provided with at least one delay circuit 40 connected in series with the second control end 301, each delay circuit 40 is powered by the distribution box 200, and the self-locking unit is used for controlling the second switching element 30 to be closed after the distribution box 200 is powered and delayed by a preset time through the delay circuit 40, so as to conduct the power supply branch, namely, form a powered state. The power-on voltage is derived from the distribution box 200, the distribution box 200 is an uncontrolled power supply at the initial stage of pre-charging, and the self-locking unit can be powered by detecting the pre-charging voltage of the distribution box 200, and controlling the distribution box 200 after the pre-charging is judged to be completed through the pre-charging voltage. As shown in fig. 2, in one embodiment, the second switching element 30 is a power relay 31, the coil of the power relay 31 is connected in parallel with the second freewheeling diode 72, the first delay circuit includes a first diode 81, a resistive-capacitive delay circuit 41 and a third resistor 13 that are sequentially connected in series, the second delay circuit includes a second diode 82, a digital delay circuit 42 and a fourth resistor 14 that are sequentially connected in series, one end of the first delay circuit provided with the first diode 81 and one end of the second delay circuit provided with the second diode 82 are connected with the distribution box 200, and one end of the first delay circuit provided with the third resistor 13 and one end of the second delay circuit provided with the fourth resistor 14 are connected with the coil of the power relay 31. The third resistor 13 and the fourth resistor 14 are lower current limiting resistors, and the values of the two resistors should be satisfied that the coils of the power relay 31 can work in the rated voltage range when the two resistors are simultaneously connected or any one resistor fails.

In this embodiment, by providing the first switching element 20 with a control end, remote control of precharge can be achieved, and power-on self-locking can be achieved through design of the distribution box 200 and the delay circuit, so that reliability of a power-on state is ensured. The service life of the parts can be prolonged by arranging the pre-charging loop.

In another embodiment, the self-locking unit includes two parallel first delay circuits and second delay circuits of different types, each of which is capable of delaying for a preset time. For example, the first delay circuit is a resistor Rong Yanshi circuit 41, the second delay circuit is a digital delay circuit 42, and the design of the different delay circuits (namely, two paths of dissimilar dual-redundancy delay circuits) can further improve the reliability of power-on self-locking due to different delay principles of the two delay circuits. For example, the reason for failure of the rc delay circuit 41 is often different from the reason for failure of the digital delay circuit 42, so that when one failure reason occurs in the circuit, the other delay circuit can still operate normally, so as to ensure the power-on self-locking function. The delay time should be greater than the precharge time, and the delay time is dependent on the precharge voltage, thereby designing the delay circuit.

In this embodiment, the delay is performed by using a hardware delay circuit, and in other embodiments, a software delay circuit may also be used.

In another embodiment, the control unit further comprises a power-down control circuit, which comprises a power-down branch connected to the second control terminal 301, and a third switching element with a third control terminal is arranged on the power-down branch, so as to control the power-down control by controlling the third control terminal to turn off the power branch.

As shown in fig. 2, in one embodiment, the third switching element is a power-down control relay 51, one end of a coil of the power-down control relay 51 is connected in series with the fifth resistor 15 and then connected to the output end of the power supply 100, and the other end of the coil of the power-down control relay 51 is connected to the wireless charging module, and the coil of the power-down control relay 51 is further connected in parallel with the third freewheeling diode 73. The fifth resistor 15 and the coil resistor of the power-down control relay 51 are divided such that the coil resistor of the power-down control relay 51 operates in the rated voltage range.

In this embodiment, when the wireless charging module provides the power-down ground-on signal, the contacts of the power-down control relay 51 are closed, so that the coil of the power relay 31 is short-circuited, and the contacts are opened, thereby realizing power-down of the whole machine.

In other embodiments, power down may also be achieved by controlling the power supply 100 output to be turned off.

In a further embodiment, the control unit further comprises a power down locking control circuit comprising a fourth switching element arranged on the power down branch and having a fourth control terminal, so as to control the power down branch to be disconnected and the power supply branch to be always connected by controlling the fourth control terminal.

As shown in fig. 2, in one embodiment, the fourth switching element is a down-locking relay 61, one end of the coil of the down-locking relay 61 is connected to the flight management unit, the other end is grounded, and the coil of the down-locking relay 61 is further connected in parallel with a fourth freewheeling diode 74. In one embodiment, the lower electrically-latched relay 61 is selected to be a normally-closed relay.

In this embodiment, the normally closed contact of the power-down locking relay 61 and the normally open contact of the power-down control relay 51 form a power-down branch, and a power-down locking signal is provided to the power-down locking relay 61 through the flight management unit, so that the normally closed contact of the power-down locking relay 61 is opened, and a power-down locking state is formed at this time, and even if the contact of the power-down control relay 51 is closed, power cannot be turned off. The unmanned aerial vehicle is automatically allowed to be powered down only after falling under any condition, so that reliable power-down locking is realized.

The control unit provided in the above embodiment, which is cross-linked with the distribution box 200, the wireless charging module and the flight management unit, can realize the functions of remote control precharge, power-on and power-off, power-on locking and power-off locking of the whole unmanned aerial vehicle, so that the unmanned aerial vehicle is unattended in the whole process of landing, charging and taking off.

In other embodiments, each of the above-mentioned switching elements may also be a relay, an optocoupler, a morse tube, an integrated circuit, or the like. The control signals provided by the wireless charging module or the flight management unit may also be provided by the battery management system or the distribution box controller. The above ground open signal, i.e. low active, may also be changed to high active. Parameters of each component are calculated according to actual requirements, and the model selection is selected according to actual weight and volume requirements.

Fig. 3 is a schematic diagram of a power interface for a control unit of a wireless charging drone according to one embodiment of the present invention. Fig. 4 is a schematic diagram of a control interface for a control unit of a wireless charging drone according to one embodiment of the present invention. Fig. 5 is a schematic diagram of a power-on pre-charge control circuit for a control unit of a wireless charging drone, according to one embodiment of the present invention. Fig. 6 is a schematic diagram of a power down control circuit and a power down lock control circuit for a control unit of a wireless charging drone according to one embodiment of the present invention.

Fig. 7 is a schematic diagram of the resistor Rong Yanshi circuit 41 for the control unit of the wireless charging drone according to one embodiment of the present invention. Fig. 8 is a schematic diagram of a digital delay circuit 42 for a control unit of a wireless charging drone according to one embodiment of the present invention. Fig. 9 is a schematic diagram of an internal buck regulator circuit for a control unit of a wireless charging drone according to one embodiment of the present invention. In another embodiment, the present application further specifically designs a PCB board integrated with the above functions, as shown in fig. 3 to fig. 9, where the pins with the same symbols are correspondingly connected. In fig. 3, the TP2 pin of the power interface is connected to the output end of the battery, the TP1 pin is used for outputting to the load, in fig. 4, the TP4 pin and the TP5 pin of the control interface are both connected to the distribution box 200, TP6 provides power (k+) for the control end of the power relay 31, and the TP7 pin is the ground (K-) of the power relay 31. The diodes D1 and D2 are used for stabilizing the voltage output from the distribution box 200, and the diode D4 is used for absorbing the reverse electromotive force at the two ends of the coil of the voltage relay, which corresponds to the function of the second freewheeling diode 72. In FIG. 5, a U1 chip (model G3VM-101AR 1) is used, and the output of the battery is controlled to be communicated with a load through an ON signal, so that power-ON control is completed, wherein a ceramic resistor of 30R/6W/0.5s can be externally connected between RA1 and RA 2. In fig. 6, the diodes D16 and D17 may be configured to conduct the output voltage of the distribution box 200 in a unidirectional manner, and then output the voltage to the power-down locking control circuit, where the power-down control circuit and the relays in the power-down locking control circuit in fig. 6 are implemented by using relay chips, that is, U2A and U2B chips may be selected from the chips with the types HFKA/012-2ZPT, and the diodes D6 and D9 in fig. 6 are equivalent to the fourth freewheeling diode 74 and the third freewheeling diode 73, and are grounded through the input control k+ terminal of the OFF signal, and turned OFF through the input control k+ terminal of the LOCK signal, so as to form the power-down locking state. FIGS. 7 and 8 correspond to the resistor Rong Yanshi circuit 41 and the digital delay circuit 42, respectively, which are specifically connected between RB1 and RB2 as shown in the drawing, and 10R/15W/0.5s and 1.5W long-time ceramic resistors are respectively connected between RC1 and RC 2. Since the above circuits need to use 5V voltage, the circuit also needs to convert the 12V voltage output by the distribution box 200 into 5V, so the internal voltage-reducing and stabilizing circuit of fig. 9, which is 12V to 5V, is designed, and a U4 chip with model number ADP7118AUJZ-5.0 can be selected for implementation.

It should be noted that, after the selection, the power relay 31 and the fifth resistor 15 are not mounted on the PCB board because of their large volume, so the circuit diagram does not include the power relay 31 and the fifth resistor 15, and only the soldering interface is reserved.

The invention also provides a unmanned aerial vehicle comprising the control unit in any one of the embodiments or the combination of the embodiments.

Fig. 10 is a flowchart of a control method according to an embodiment of the present invention. The present invention also provides a control method for the control unit, as shown in fig. 10, and in one embodiment, the method includes:

step S100, a battery charging instruction is received and a battery of the wireless charging module is charged according to the battery charging instruction. This battery charging command may be issued by the ground station.

Step S200, after the battery of the wireless charging module is charged, the pre-charging branch is controlled to be conducted according to the pre-charging control instruction. That is, the battery is precharged to the distribution box 200, where a precharge control command may be generated by the wireless charging module after the battery of the wireless charging module is charged, and sent to the first control terminal of the first switching element.

Step S300, judging whether the precharge is completed, if yes, proceeding to step S400, otherwise proceeding to step S500.

Step S400, after the pre-charging branch is turned on, the self-locking unit works to turn on the power branch after the power box 200 is powered on for a preset time. At this time, the power supply branch can be automatically turned on in a delayed manner after the self-locking unit is powered on because the distribution box 200 can power the self-locking unit. Of course in other embodiments the operation of the self-locking unit may also be controlled by the flight management unit.

After the power-on is completed, the flight management unit can also send a power-off locking control instruction to the power-off locking control circuit so as to control the power-off locking control circuit to disconnect the power-off branch circuit, so that the power supply branch circuit is kept always connected.

And S500, performing fault reporting, namely generating a fault signal, and feeding back to the ground station.

In a further embodiment, step S400 further comprises:

step S600, power-on self-test is performed, if the self-test is successful, step S700 is performed, otherwise step S800 is performed.

Step S700, feeding back a signal that the power-on self-test is successful to the ground station.

Step S800, the power-down control circuit is controlled to work according to the power-down control instruction so as to control the power supply branch to be disconnected, and power-down is completed. Here, the power-down control command may be issued by the wireless charging module, and step S800 may be entered after step S500.

By now it should be appreciated by those skilled in the art that while a number of exemplary embodiments of the invention have been shown and described herein in detail, many other variations or modifications of the invention consistent with the principles of the invention may be directly ascertained or inferred from the present disclosure without departing from the spirit and scope of the invention. Accordingly, the scope of the present invention should be understood and deemed to cover all such other variations or modifications.

Claims

1. A control unit for a wireless charging unmanned aerial vehicle, comprising:

the self-locking unit is provided with at least one delay circuit connected with the second control end in series, each delay circuit is powered by the distribution box, and the self-locking unit is used for controlling the second switching element to be closed after the distribution box is electrified and the delay circuit delays for a preset time so as to conduct the power supply branch;

the self-locking unit comprises two parallel first delay circuits and second delay circuits which are different in type, and the first delay circuits and the second delay circuits can both delay the preset time;

the second switch element is a power relay, a coil of the power relay is connected with a second follow current diode in parallel, the first delay circuit comprises a first diode, a resistance-capacitance delay circuit and a third resistor which are sequentially connected in series, the second delay circuit comprises a second diode, a digital delay circuit and a fourth resistor which are sequentially connected in series, one end of the first diode and one end of the second delay circuit are connected with the distribution box, one end of the third resistor and one end of the fourth resistor are connected with the coil of the power relay.

2. The control unit of claim 1, further comprising:

3. The control unit of claim 2, further comprising:

4. A control unit according to claim 3, wherein,

the first switch element is a pre-charging relay, one end of a coil of the pre-charging relay is connected in series with a second resistor, the other end of the coil of the pre-charging relay is connected with the wireless charging module, one end of the second resistor, which is far away from the coil of the pre-charging relay, is connected with the output end of the power supply, and the coil of the pre-charging relay is also connected with the first freewheeling diode in parallel.

5. The control unit of claim 4, wherein the control unit is configured to control the control unit,

the third switching element is a power-down control relay, one end of a coil of the power-down control relay is connected with the output end of the power supply after being connected with the fifth resistor in series, the other end of the coil of the power-down control relay is connected with the wireless charging module, and the coil of the power-down control relay is also connected with the third freewheeling diode in parallel.

6. The control unit of claim 5, wherein the control unit is configured to control the control unit,

the fourth switching element is a lower electric locking relay, one end of a coil of the lower electric locking relay is connected with the flight management unit, the other end of the coil of the lower electric locking relay is grounded, and the coil of the lower electric locking relay is also connected with the fourth freewheel diode in parallel.

7. A drone comprising a control unit according to any one of claims 1 to 6.

8. A control method for the control unit according to any one of claims 1 to 6, characterized in that the control method comprises: