KR102529824B1 - Unmanned aerial vehicle using hybrid power system and its control method - Google Patents

Abstract

The present invention relates to an unmanned aerial vehicle using a hybrid power system and a control method thereof. An unmanned aerial vehicle using a hybrid power system according to the present invention stores power generated from a plurality of motors that provide power to a propeller, a generator that generates power, an engine that drives the generator using fuel, and a plurality of motors. A battery that supplies power to a plurality of inverters for driving a corresponding motor among a plurality of motors according to a motor control PWM signal, and a motor control PWM signal transmitted to the plurality of inverters and a motor control PWM signal transmitted to the plurality of inverters. It includes a flight control computer that calculates the value obtained by summing the PWM values of . The engine drives the generator according to the engine control PWM signal generated based on the PWM sum value.

Description

Unmanned aerial vehicle using hybrid power system and its control method

The present invention relates to an unmanned aerial vehicle using a hybrid power system and a control method thereof.

Conventional multicopter-type small drones (unmanned aerial vehicles) use batteries as their main power source, so their flight time is as short as 30 minutes at most, so mission performance is very limited.

Drones powered by batteries do not require a separate power control device, and based on the discharged energy of the battery, the motor-propeller output is controlled appropriately for the drone's flight mission.

As a way to overcome the short flight time of the battery, a hybrid power system combining an engine, generator, and battery is being applied to drones, and when using a hybrid power system, the drone's flight time can be increased by at least twice.

In order to apply the hybrid power system to drones, power control that considers engine-generator performance and battery characteristics is required. In general, a method of adjusting engine-generator output based on the system voltage maintained through the battery is used.

1 is a diagram for explaining a control method of a conventional hybrid power system.

Referring to FIG. 1, in a drone, the motor-propeller output can be adjusted by an ESC (inverter) based on a PWM signal through an FCC (flight control computer), and at this time, the system voltage of the battery varies according to the power energy used by the motor. do.

Hybrid drones generally use a method in which a flight control computer (FCC) of the drone controls motor-propeller output, and a controller (PMU) of the hybrid system separately controls the throttle of the engine accordingly.

When the system voltage fluctuates, the power management unit (PMU) of the hybrid system adjusts the throttle of the engine according to the voltage fluctuation range, thereby controlling the system voltage to return to the originally set system voltage.

In the case of existing hybrid drones, since the engine-generator output is adjusted based on the system voltage, it is difficult to respond to instantaneous output fluctuations. Since the generator output is adjusted, a time delay inevitably occurs until the actual engine-generator system generates the regulated output. may cause damage.

In the case of using this conventional method, a situation in which the charging current limit of the battery is exceeded may occur when the power system suddenly and rapidly increases, and the battery may be cut off, or the system voltage abnormally rises due to the momentary and sudden decrease in the power system. can act as

A technical problem to be solved by the present invention is to provide an unmanned aerial vehicle using a hybrid power system and a control method thereof.

A hybrid unmanned aerial vehicle according to the present invention for solving the above technical problem is a plurality of motors for providing power to a propeller, a generator for generating power, an engine for driving the generator using fuel, and power generated by the generator. and a battery for supplying power to the plurality of motors, a plurality of inverters for driving a corresponding motor among the plurality of motors according to a motor control PWM signal, and a motor control PWM signal transmitted to the plurality of inverters, and a flight control computer for obtaining a sum of PWM values of motor control PWM signals transmitted to a plurality of inverters (hereinafter referred to as 'PWM sum value').

The engine drives the generator according to an engine control PWM signal generated based on the PWM sum value.

The flight control computer may generate an engine control PWM signal.

The flight control computer may increase or decrease the PWM value of the engine control PWM signal when the output of the battery (P=VI) is out of a predetermined setting range. where V is the output voltage of the battery and I is the output current of the battery.

The hybrid unmanned aerial vehicle may further include a power controller generating the engine control PWM signal.

The power controller may increase or decrease the PWM value of the engine control PWM signal when the output of the battery is out of a predetermined setting range.

A method for controlling a hybrid unmanned aerial vehicle according to the present invention for solving the above technical problems includes transmitting a motor control PWM signal to a plurality of inverters, based on the sum of the PWM values of the motor control PWM signals transmitted to the plurality of inverters. generating and transmitting an engine control PWM signal to an engine, and increasing or decreasing a PWM value of the engine control PWM signal when an output of a battery driven by the engine is out of a predetermined setting range.

Generating an engine control PWM signal based on the PWM sum value of the motor control PWM signals transmitted to the plurality of inverters and transmitting the generated PWM signal to the engine includes transmitting the PWM sum value to the power controller by the flight control computer, and and generating, by a power controller, the engine control PWM signal based on the PWM sum value and transmitting the generated engine control PWM signal to the engine.

It may include a computer-readable recording medium on which a program for executing the method is recorded on a computer.

According to the present invention, the output of the engine-generator can be simultaneously controlled in real time in response to the total required power driven through each motor-inverter. In addition, as a method of controlling actual power without following the conventional system voltage, more stable and efficient hybrid unmanned air vehicle operation is possible.

1 is a diagram for explaining a control method of a conventional hybrid power system.
2 is a block diagram showing the configuration of a hybrid unmanned aerial vehicle according to a first embodiment of the present invention.
3 is a flowchart for explaining the operation of the hybrid unmanned aerial vehicle according to the first embodiment of the present invention.
4 is a block diagram showing the configuration of a hybrid unmanned aerial vehicle according to a second embodiment of the present invention.
5 is a flowchart for explaining the operation of a hybrid unmanned aerial vehicle according to a second embodiment of the present invention.

Then, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily practice the present invention.

2 is a block diagram showing the configuration of a hybrid unmanned aerial vehicle according to a first embodiment of the present invention.

Referring to FIG. 2 , the hybrid unmanned aerial vehicle according to an embodiment of the present invention includes propellers 10a, 10b, ..., 10n, a plurality of motors 20a, 20b, ..., 20n, a plurality of inverters 30a, 30b, ..., 30n), a flight control computer (FCC) 40, a generator 50, an engine 60, and a battery 70.

The propellers 10a, 10b, ..., 10n may rotate by receiving power from the motors (20a, 20b, ..., 20n).

The motors 20a, 20b, ..., 20n receive power from the battery 70 and provide power to the propellers 10a, 10b, ..., 10n.

The inverters 30a, 30b, ..., 30n receive the motor control PWM signal from the flight control computer 40 and drive the corresponding motors 20a, 20b, ..., 20n to generate motor thrust according to the input.

Generator 50 may generate power to supply power to motors 20a, 20b, ..., 20n and may also charge battery 70.

The engine 60 may drive the generator 50 using fuel.

The fuel may be gasoline and may be stored in a fuel storage unit (not shown) of the hybrid unmanned aerial vehicle. Of course, other types of fuel other than gasoline may also be used.

The battery 70 may store power generated by the generator 50 and supply power to the motors 20a, 20b, ..., 20n.

The flight control computer 40 performs a function of controlling the flight operation of the hybrid unmanned aerial vehicle. The flight control computer 40 may control the autonomous flight of the hybrid unmanned aerial vehicle according to a predetermined program or may control the flight operation of the hybrid unmanned aerial vehicle according to a flight control command transmitted from an external control device (not shown).

The flight control computer 40 may transmit a motor control PWM signal to the inverters 30a, 30b, ..., 30n. The flight control computer 40 may obtain a value obtained by summing the PWM values of the motor control PWM signals transmitted to the inverters 30a, 30b, ..., 30n (hereinafter, referred to as 'PWM sum value').

The flight control computer 40 may generate an engine control PWM signal based on the PWM sum value. And the flight control computer 40 may transfer the generated engine control PWM signal to the engine 60 in real time.

The engine 60 may drive the generator 70 according to an engine control PWM signal generated based on the PWM sum value.

Meanwhile, the flight control computer 40 may increase or decrease the PWM value of the engine control PWM signal when the output (P=VI) of the battery 70 is out of a predetermined setting range. where V is the output voltage of the battery and I is the output current of the battery.

For example, when the output of the battery 70 is higher than a preset range, the flight control computer 40 may decrease the PWM value of the engine control PWM signal. Conversely, when the output of the battery 70 is lower than a preset range, the flight control computer 40 may increase the PWM value of the engine control PWM signal. Here, the battery output may be obtained based on the battery output voltage and output current.

Accordingly, in the flight control computer 40 of the hybrid unmanned aerial vehicle, the output of the engine-generator can be simultaneously controlled in real time in response to the total required power driven through each motor-inverter. As a method of controlling actual power without following the conventional system voltage, more stable and efficient hybrid unmanned aerial vehicle operation is possible.

3 is a flowchart for explaining the operation of the hybrid unmanned aerial vehicle according to the first embodiment of the present invention.

2 and 3, the flight control computer 40 may transmit a motor control PWM signal to the inverters 30a, 30b, ..., 30n (S310). The inverters 30a, 30b, ..., 30n receive the motor control PWM signal and drive the corresponding motors 20a, 20b, ..., 20n, respectively.

Meanwhile, the flight control computer 40 sums the motor control PWM signals transmitted to the inverters 30a, 30b, ..., 30n in real time, generates an engine control PWM signal based on the PWM sum value, and transmits it to the engine 60. It can (S320).

Steps S310 and S320 may be performed almost simultaneously in real time.

And the flight control computer 40 may check whether the output of the battery 80 is out of a predetermined setting range (S330). In step S330, the battery output by the operation of the generator 50 and the engine 60 is monitored, and if the battery output is out of a predetermined setting range, feedback control for adjusting the engine control PWM signal may be performed.

If the battery output is out of a predetermined setting range (S330-N), the flight control computer 40 may increase or decrease the engine control PWM signal (S340).

Meanwhile, if the battery output is within a predetermined setting range (S330-Y), the flight control computer 40 may maintain the engine control PWM signal.

4 is a block diagram showing the configuration of a hybrid unmanned aerial vehicle according to a second embodiment of the present invention.

Referring to FIG. 4 , the hybrid unmanned aerial vehicle according to the second embodiment of the present invention includes propellers 10a, 10b, ..., 10n, a plurality of motors 20a, 20b, ..., 20n, and a plurality of inverters 30a, 30b. , ..., 30n), a flight control computer (FCC) 40, a generator 50, an engine 60, and a battery 70.

Among the components of the second embodiment of the present invention, descriptions of components that operate identically to those of the first embodiment will be omitted, and only differences will be described.

Unlike the first embodiment, the hybrid unmanned aerial vehicle according to the second embodiment of the present invention may further include a power management unit (PMU) 80.

The power controller 80 may perform a function of controlling a hybrid power system including the generator 50, the engine 60, and the battery 70.

The flight control computer 40 transmits the PWM sum value to the power controller 80 .

The power controller 80 may generate an engine control PWM signal based on the PWM sum value transmitted from the flight control computer 40 . Also, the power controller 80 may transmit the generated engine control PWM signal to the engine 60 in real time.

The power controller 80 may increase or decrease the PWM value of the engine control PWM signal when the output of the battery 70 is out of a predetermined setting range. For example, when the output of the battery 70 is higher than a preset range, the power controller 80 may decrease the PWM value of the engine control PWM signal. Conversely, when the output of the battery 70 is lower than a preset range, the power controller 80 may increase the PWM value of the engine control PWM signal. Here, the battery output may be obtained based on the battery output voltage and output current.

As a result, the power controller 80 of the hybrid unmanned aerial vehicle can simultaneously control the output of the engine-generator in real time in response to the total required power driven through each motor-inverter. As a method of controlling actual power without following the conventional system voltage, more stable and efficient hybrid unmanned aerial vehicle operation is possible.

5 is a flowchart for explaining the operation of a hybrid unmanned aerial vehicle according to a second embodiment of the present invention.

4 and 5, the flight control computer 40 may transmit a motor control PWM signal to the inverters 30a, 30b, ..., 30n (S510). The inverters 30a, 30b, ..., 30n receive the motor control PWM signal and drive the corresponding motors 20a, 20b, ..., 20n, respectively.

Meanwhile, the flight control computer 40 transmits the sum of the motor control PWM signals transmitted to the inverters 30a, 30b, ..., 30n to the power controller 80 in real time (S515).

Then, the power controller 80 may generate an engine control PWM signal based on the PWM sum value and transmit the generated engine control PWM signal to the engine 60 (S520).

Steps S510, S515, and S520 may be performed almost simultaneously in real time.

Further, the power controller 80 may check whether the output of the battery 80 is out of a predetermined setting range (S530). In step S530, the battery output by the operation of the generator 50 and the engine 60 is monitored, and if the battery output is out of a predetermined setting range, feedback control for adjusting the engine control PWM signal may be performed.

When the battery output is out of a predetermined setting range (S530-N), the power controller 80 may increase or decrease the engine control PWM signal (S540).

Meanwhile, if the battery output is within a predetermined setting range (S530-Y), the power controller 80 may maintain the engine control PWM signal.

The embodiments described above may be implemented as hardware components, software components, and/or a combination of hardware components and software components. For example, the devices, methods and components described in the embodiments may include, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate (FPGA). array), programmable logic units (PLUs), microprocessors, or any other device capable of executing and responding to instructions. A processing device may run an operating system (OS) and one or more software applications running on the operating system. A processing device may also access, store, manipulate, process, and generate data in response to execution of software. For convenience of understanding, there are cases in which one processing device is used, but those skilled in the art will understand that the processing device includes a plurality of processing elements and/or a plurality of types of processing elements. It can be seen that it can include. For example, a processing device may include a plurality of processors or a processor and a controller. Other processing configurations are also possible, such as parallel processors.

Software may include a computer program, code, instructions, or a combination of one or more of the foregoing, which configures a processing device to operate as desired or processes independently or collectively. The device can be commanded. Software and/or data may be any tangible machine, component, physical device, virtual equipment, computer storage medium or device, intended to be interpreted by or provide instructions or data to a processing device. may be permanently or temporarily embodied in Software may be distributed on networked computer systems and stored or executed in a distributed manner. Software and data may be stored on one or more computer readable media.

The method according to the embodiment may be implemented in the form of program instructions that can be executed through various computer means and recorded on a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. Program commands recorded on the medium may be specially designed and configured for the embodiment or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. - includes hardware devices specially configured to store and execute program instructions, such as magneto-optical media, and ROM, RAM, flash memory, and the like. Examples of program instructions include high-level language codes that can be executed by a computer using an interpreter, as well as machine language codes such as those produced by a compiler. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

As described above, although the embodiments have been described with limited drawings, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

10a, 10b, ... , 10n: propeller
20a, 20b, . . . , 20n: motor
30a, 30b, . . . , 30n: Inverter
40: Flight Control Computer (FCC)
50: generator
60: engine
70: battery
80: power controller (PMU)

Claims (8)

A plurality of motors that provide power to the propellers;
generators that generate electricity,
An engine that drives the generator using fuel,
A battery for storing power generated by the generator and supplying power to the plurality of motors;
A plurality of inverters for driving a corresponding motor among the plurality of motors according to a motor control PWM signal, and
A flight control computer that transmits each of the motor control PWM signals to the plurality of inverters and obtains in real time a value obtained by summing the PWM values of the motor control PWM signals transmitted to the plurality of inverters (hereinafter referred to as 'PWM sum value')
including,
The engine drives the generator according to an engine control PWM signal generated in real time based on the PWM sum value. In claim 1,
An unmanned aerial vehicle using a hybrid power system in which the flight control computer generates an engine control PWM signal. In paragraph 2,
The flight control computer increases or decreases the PWM value of the engine control PWM signal when the output of the battery is out of a predetermined setting range. In claim 1,
An unmanned aerial vehicle using a hybrid power system further comprising a power controller for generating the engine control PWM signal. In paragraph 4,
The power controller increases or decreases the PWM value of the engine control PWM signal when the output of the battery is out of a predetermined setting range. Transmitting motor control PWM signals to a plurality of inverters, respectively;
Generating an engine control PWM signal based on the PWM sum of the motor control PWM signals transmitted to each of the plurality of inverters and transmitting the PWM signal to the engine in real time; and
increasing or decreasing the PWM value of the engine control PWM signal when the output of the battery driven by the engine is out of a predetermined setting range;
Control method of an unmanned aerial vehicle using a hybrid power system comprising a. In paragraph 6,
Generating an engine control PWM signal based on the PWM sum of the motor control PWM signals transmitted to the plurality of inverters and transmitting the generated engine control PWM signal to the engine,
The flight control computer transmitting the PWM sum value to the power controller, and
Generating, by the power controller, the engine control PWM signal based on the PWM sum value and transmitting it to the engine
Control method of an unmanned aerial vehicle using a hybrid power system comprising a. A computer-readable recording medium recording a program for executing the method according to claim 6 or 7.

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