Powertrain control system for vertical take-off and landing aircraft

Abstract

To provide a powertrain control system and a method for a vertical take-off and landing flight vehicle, which can always maintain a battery SOC (State of Charge) at a certain level or more.SOLUTION: A power train control system for a vertical take-off and landing flight vehicle of the present invention is configured to include: rotor drive motors coupled to rotors of the vertical take-off and landing flight vehicle in a power transmittable manner; a battery coupled to the rotor drive motors in an electric power suppliable manner; a power generator connected to the battery in a chargeable and dischargeable manner; an engine connected to the power generator in a power transmittable manner; and a control unit for controlling driving of the engine and the power generator to charge the battery and for determining propriety of standby of the vertical take-off and landing flight vehicle for takeoff and landing.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a powertrain control system and method for a vertical take-off and landing vehicle, and more particularly to a powertrain control system and method for a vertical take-off and landing vehicle that can always manage a battery SOC above a certain level during each flight phase of the vertical take-off and landing vehicle, i.e., can maintain a remaining battery charge above a certain level. [Background technology]

[0002] In recent years, vertical take-off and landing (VTOL) aircraft using rotors or propellers have been attracting attention as urban air mobility (UAM) for future transportation and shipping systems. As shown in FIG. 1, a vertical take-off and landing (VTOL) aircraft 100 is an aircraft capable of vertical take-off, landing, and flight using rotors or propellers. It basically comprises a body 110 for passengers, wing sections 120 formed on both sides of the body 110, and a propeller-type rotor 130 rotatably attached to the outer end of the wing section 120 to generate substantial lift. The powertrain for driving the VTOL aircraft can be an internal combustion engine type in which the output shaft of an engine 20 is directly connected to the rotor 130, as shown in FIG. 2, or an electric type in which the output shaft of a rotor drive motor 10 is directly connected to the rotor 130 and a battery 40 is connected to the motor 10 to supply power, as shown in FIG. 3.

[0003] As shown in Figure 1, the entire flight process of such a vertical take-off and landing aircraft is carried out in the following order: (1) prepare for take-off; (2) vertical take-off, in which the aircraft ascends vertically to a certain height; (3) hovering, in which the aircraft pauses for horizontal flight preparation; (4) transition, in which the aircraft moves to a higher altitude for horizontal flight; (5) acceleration, in which the aircraft accelerates to a speed for horizontal flight; (6) cruising, in which the aircraft cruises at a certain speed to the destination; (7) deceleration, in which the aircraft slows down for landing near the destination; (8) transition, in which the aircraft moves to a higher altitude for vertical landing; (9) hovering, in which the aircraft pauses for vertical landing preparation; (10) vertical landing, in which the aircraft descends vertically to the destination; and (11) completing vertical landing at the destination.

[0004] Generally, the most power required for an engine or motor to drive flight is required during the vertical takeoff, vertical landing, hovering, and transition stages of an aircraft's entire flight. In particular, in the case of a vertical takeoff and landing (VTOL) aircraft equipped with an electric powertrain, the motor's output power, which uses battery power, is high during the takeoff stage when the battery's State of Charge (SOC) is sufficient. However, during the landing stage after the cruising stage, where the battery is continuously discharged, the battery's SOC may be insufficient, resulting in insufficient motor power and adversely affecting the aircraft's flight control. Therefore, to maintain the battery SOC above a certain level throughout the aircraft's entire flight, the number of batteries installed in the aircraft may be increased, but this can result in problems such as increased aircraft weight and costs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2015-064767 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made to solve these problems, and an object of the present invention is to provide a powertrain control system and method for a vertical take-off and landing aircraft that employs a hybrid type powertrain in which the rotor drive motor output shaft is directly connected to the rotor, a battery is connected to the rotor drive motor so as to be able to supply power, and an engine and generator are connected to the battery so as to be able to charge and discharge, and that controls the operation of the engine and generator according to the motor power required and battery SOC at each flight stage of the vertical take-off and landing aircraft, thereby maintaining the battery SOC at a constant level or above. [Means for solving the problem]

[0007] A powertrain control system for a vertical take-off and landing aircraft according to the present invention includes a rotor drive motor connected to a rotor of the vertical take-off and landing aircraft so as to be capable of transmitting power, a battery connected to the rotor drive motor so as to be able to supply power, a generator connected to the battery so as to be able to charge and discharge, an engine connected to the generator so as to be able to transmit power, and a control device that controls operation of the engine and the generator to charge the battery and determines whether the vertical take-off and landing aircraft is ready for take-off and landing.

[0008] The control device includes a flight controller that provides motor power requirement and current flight phase information of the VTOL vehicle; a battery controller that provides battery SOC information, battery discharge limit value information, and battery charge limit value information; an engine controller that provides a catalyst heating request signal, an oxygen sensor diagnosis request signal, and current engine RPM information; a generator controller that provides generator torque limit value and generator RPM information; and a main controller that controls the operation of the engine and generator based on the information provided by the flight controller, battery controller, engine controller, and generator controller, and determines whether to grant takeoff permission or hold for takeoff or whether to grant landing permission or hold for landing of the VTOL vehicle.

[0009] The main controller includes an engine driving mode determination unit that determines the engine driving mode to be one of engine stop, engine passive run, engine idle, engine partial load, and engine full load; an engine driving amount calculation unit that calculates an engine target torque and an engine target RPM for battery charging; an engine required torque determination unit that determines engine fuel injection permission, an engine torque command, catalyst heating permission, and engine self-diagnosis permission; a generator required torque determination unit that determines a generator torque command; and a takeoff and landing hold request unit that determines takeoff and landing hold for the vertical takeoff and landing aircraft.

[0010] The engine driving mode determining unit determines the engine driving mode to be an engine partial load or an engine full load so that the battery charging can be assisted by the engine output when the motor required power is above a certain level.

[0011] The engine driving mode determination unit determines the engine driving mode to be an engine partial load or an engine full load so that the battery can be charged by driving a generator driven by the engine when it is determined that the battery SOC is equal to or lower than a reference value or the battery discharge limit value is equal to or lower than a reference value.

[0012] The engine driving mode determining unit determines the engine driving mode to be engine idle when a catalyst heating request signal is received, so as to heat the catalyst to a predetermined temperature or higher before takeoff.

[0013] The engine driving mode determining unit determines the engine driving mode to be engine passive run when an oxygen sensor diagnosis request signal for engine self-diagnosis is received.

[0014] The engine required torque determination unit is configured to transmit to the engine controller, if the engine driving mode is determined to be engine partial load or engine full load, a signal for determining permission for fuel injection to the engine in conjunction with the current engine RPM, and an engine torque command for adjusting the engine torque and RPM to be less than the generator torque limit value while reaching the engine target torque and RPM.

[0015] The engine required torque determination unit is configured to transmit a signal determining permission for fuel injection to the engine and a catalyst heating permission signal to the engine controller in conjunction with a current engine RPM if the engine driving mode is determined to be engine idle.

[0016] The engine required torque determination unit is configured to transmit an engine self-diagnosis enable signal to the engine controller in conjunction with a current engine RPM if the engine driving mode is determined to be engine passive run.

[0017] The takeoff and landing standby request unit is configured to transmit a takeoff standby signal to a flight controller if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if catalyst heating is being performed in an engine idle state.

[0018] The takeoff and landing hold request unit is configured to transmit a landing hold signal to the flight controller if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if the engine RPM is below a reference value but there is no fuel injection.

[0019] A powertrain control method for a vertical take-off and landing aircraft according to the present invention includes: determining a current flight stage of the vertical take-off and landing aircraft; driving an engine by sequentially performing an engine driving mode determination step, an engine driving amount calculation step, an engine required torque determination step, and a generator required torque determination step according to the determined flight stage; and driving a generator by driving the engine and charging a battery with power generated by the generator.

[0020] If the engine drive mode is determined to be partial engine load or full engine load according to the determined flight phase, the target engine torque and target engine RPM are calculated, and if fuel injection permission and engine torque command for the engine are determined, the generator is driven by driving the engine, and the battery is charged with the power generated by the generator.

[0021] If the current flight stage is determined to be a takeoff preparation stage, the engine driving mode determination step, the engine driving amount calculation step, the engine required torque determination step, and the generator required torque determination step are sequentially performed, and then a step of determining whether to wait for takeoff is performed.

[0022] If a catalyst heating request signal is received in the engine driving mode determining step, the engine driving mode is determined to be engine idle, and the catalyst is heated to a predetermined temperature or higher before takeoff.

[0023] In the step of determining whether to hold for takeoff, if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if catalyst heating is continuously performed, the main controller transmits a takeoff hold request signal to the flight controller to maintain the VTOL aircraft in a takeoff hold state.

[0024] When the current flight stage is determined to be a cruising stage or a takeoff waiting stage and there is an oxygen sensor diagnosis request signal for engine self-diagnosis, the engine driving mode is determined to be engine passive run, and engine self-diagnosis is performed by analyzing the detection signal of the oxygen sensor.

[0025] If the current flight stage is determined to be a cruising stage approaching the destination, the engine driving mode determining step, the engine driving amount calculating step, the engine required torque determining step, and the generator required torque determining step are sequentially performed, and then a step of determining whether to wait for landing is performed.

[0026] In the step of determining whether to perform landing standby, if it is determined that the battery SOC is below a reference value, the battery discharge limit value is below a reference value, the engine RPM is below a reference value, or fuel is not being injected, the main controller transmits a landing standby request signal to the flight controller to maintain the VTOL aircraft in a landing standby state. [Effects of the Invention]

[0027] The present invention has the following effects. First, the battery SOC can be maintained above a certain level at each flight stage of a VTOL vehicle, thereby preventing battery SOC deficiency and motor output deficiency, enabling the VTOL vehicle to fly stably. Second, emissions can be reduced by catalytic heating before takeoff. Thirdly, there is an advantage that engine self-diagnosis is possible by requesting oxygen sensor diagnosis. Fourth, the battery can be charged by driving the engine and the generator, which reduces the battery capacity and eliminates the need for a separate external charger connection part, thereby reducing costs. [Brief explanation of the drawings]

[0028] [Figure 1]1 is a schematic diagram showing a vertical take-off and landing air vehicle for urban air mobility and its flight stages. [Figure 2] FIG. 1 is a schematic diagram illustrating an internal combustion engine type powertrain applied to a vertical take-off and landing vehicle. [Figure 3] FIG. 1 is a schematic diagram showing an electric type powertrain applied to a vertical take-off and landing aircraft. [Figure 4] 1 is a schematic diagram showing a hybrid type powertrain applied to a vertical take-off and landing aircraft according to the present invention. [Figure 5] 1 is a block diagram showing a control device for a powertrain control system for a vertical take-off and landing aircraft according to the present invention. [Figure 6] 3 is a flowchart illustrating a powertrain control method for a vertical take-off and landing aircraft according to the present invention. [Figure 7] 3 is a flowchart illustrating a powertrain control method for a vertical take-off and landing aircraft according to the present invention. [Figure 8] 3 is a flowchart illustrating a powertrain control method for a vertical take-off and landing aircraft according to the present invention. [Figure 9] 3 is a flowchart illustrating a powertrain control method for a vertical take-off and landing aircraft according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 4 is a schematic diagram showing a hybrid-type powertrain applied to a vertical take-off and landing (VTOL) vehicle according to the present invention. As shown in FIG. 4, the powertrain of the VTOL vehicle according to the present invention is a hybrid-type powertrain in which the output shaft of a rotor drive motor 10 is directly connected to a rotor 130 to transmit power, a battery 40 is connected to the rotor drive motor 10 to supply power, and an engine 20 and a generator 30, which are connected in series, are connected to the battery 40 to charge and discharge the battery 40. More specifically, the generator 30 is connected to the battery 40 to charge and discharge the battery 40, and the engine 20 is connected to the generator 30 to transmit power. Therefore, when the rotor drive motor 10 is driven by receiving power from the battery 40, the rotor 130, which is connected to the output shaft of the rotor drive motor 10, is rotated, thereby completing the entire flight process of the VTOL vehicle, and the battery 40 is charged by driving the engine 20 and the generator 30.

[0030] Here, the entire flight process of a vertical take-off and landing aircraft using a hybrid-type powertrain can be performed in the following order, as described above with reference to FIG. 1: (1) prepare for take-off; (2) vertical take-off, in which the aircraft ascends vertically to a certain height; (3) hovering, in which the aircraft pauses for horizontal flight preparation; (4) transition, in which the aircraft moves to a higher altitude for horizontal flight; (5) acceleration, in which the aircraft accelerates to a speed for horizontal flight; (6) cruising, in which the aircraft cruises at a certain speed to the destination; (7) deceleration, in which the aircraft slows down for landing near the destination; (8) transition, in which the aircraft moves to a higher altitude for vertical landing; (9) hovering, in which the aircraft pauses for vertical landing preparation; (10) vertical landing, in which the aircraft descends vertically to the destination; and (11) completing vertical landing at the destination.

[0031] Another key feature of the present invention is that, throughout the entire flight of such a VTOL aircraft, the battery SOC can be maintained above a certain level by charging the battery 40 with the power generated by the generator 30 driven by the engine 20 according to the motor power demand, battery SOC, etc. To this end, the powertrain control system of the present invention includes a control device 200 for controlling the operation of the engine and generator according to the motor power demand, battery SOC, etc.

[0032] 5 is a block diagram of a control device for a powertrain control system of a vertical take-off and landing (VTOL) aircraft according to the present invention. As shown in FIG. 5, the control device 200 includes a main controller 210, which is a top-level controller, a flight controller 220, a battery controller 230, an engine controller 240, and a generator controller 250. Alternatively, a single integrated controller may be used. The flight controller 220 controls the rotor drive motor 10 and flight process, and provides the main controller 210 with required motor power (required power of the rotor drive motor) and current flight stage information, which is one of stages (1) to (11) that indicate the entire flight process of the VTOL aircraft. The control device 200 is configured to receive a take-off or landing hold command from the main controller 210.

[0033] The battery controller 230 is configured to provide battery SOC information, as well as battery discharge limit (DchLmt) and battery charge limit (ChgLmt) information to the main controller 210. When the temperature of a catalyst for purifying engine exhaust gas is below a reference value, the engine controller 240 provides a catalyst heating (CH) request signal, an oxygen sensor diagnosis request signal for engine self-diagnosis, current engine RPM information, etc. to the main controller 210, and is configured to receive an engine fuel injection enable signal, an engine torque command, a catalyst heating enable signal for purifying engine exhaust gas, an engine self-diagnosis enable signal, etc. from the main controller 210.

[0034] The generator controller 250 is configured to provide the main controller 210 with information on the generator torque limit (Lmt) and generator RPM, and to receive a generator torque command from the main controller 210. The main controller 210 is configured to control the operation of the engine and generator and determine takeoff permission or takeoff hold, or determine landing permission or landing hold, based on information provided from the flight controller 220, the battery controller 230, the engine controller 240, and the generator controller 250. To this end, the main controller 210 may include an engine drive mode determination unit 211, an engine drive amount calculation unit 212, an engine required torque determination unit 213, a generator required torque determination unit 214, a takeoff / landing hold request unit 215, etc.

[0035] The engine drive mode determination unit 211 is configured to determine the engine drive mode as one of engine stop, engine passive run in which the engine is rotated by the generator, engine idle, engine part load, and engine full load based on the motor required power and current flight stage information provided from the flight controller 220, battery SOC and battery discharge limit (DchLmt) information provided from the battery controller 230, a catalyst heating (CH) request signal and an oxygen sensor diagnosis request signal provided from the engine controller 240, etc.

[0036] For example, when the engine drive mode determination unit 211 determines the engine drive mode, if it determines that the motor required power is above a certain level during the current flight stage, the engine drive mode can be determined to be an engine partial load in which the maximum engine torque is output when the engine is driven with engine lambda (stoichiometric air-fuel ratio) < 1, or an engine full load in which the maximum torque that the engine can generate is output, so that the engine output can assist battery charging in consideration of the increase in battery discharge amount.

[0037] Alternatively, when the engine driving mode determination unit 211 determines that the battery SOC is below a reference value or that the battery discharge limit value is below a reference value, the engine driving mode may be determined to be one of engine partial load and engine full load so that the battery can be charged by driving a generator driven by the engine. Alternatively, when the engine driving mode determination unit 211 determines that the engine driving mode is based on a catalyst heating (CH) request signal, the engine driving mode may be determined to be engine idle so that the catalyst is heated to a certain temperature or higher before takeoff. Alternatively, when the engine driving mode determination unit 211 determines that the engine driving mode is based on an oxygen sensor diagnosis request signal for engine self-diagnosis, the engine driving mode may be determined to be engine passive run, and an engine self-diagnosis enable signal may be transmitted to the engine controller 240 in conjunction with the current engine RPM.

[0038] The engine driving amount calculation unit 212 calculates the engine driving amount for battery charging, and is configured to calculate the target engine torque and target engine RPM for battery charging based on the engine driving mode determined by the engine driving mode determination unit 211, motor required power information provided by the flight controller 220, battery charge limit value (ChgLmt) and battery discharge limit value (DchLmt) information including battery SOC provided by the battery controller 230, generator torque limit value (Lmt) information provided by the generator controller 250, etc.

[0039] For example, if the motor required power is above a certain level that increases the battery discharge amount, or the battery SOC is below a reference value, or the battery discharge limit value is below a reference value, and the engine driving mode is determined to be one of engine idle, engine partial load, and engine full load, the engine driving amount calculation unit 212 calculates a target torque and a target RPM of the engine for driving the generator so that the battery can be charged by driving the generator.

[0040] The engine required torque determination unit 213 is configured to determine fuel injection permission for the engine, engine torque command, catalyst heating (CH) permission, engine self-diagnosis permission, etc. based on the engine driving mode determined by the engine driving mode determination unit 211, the engine target torque and RPM information calculated by the engine driving amount calculation unit 212, current engine RPM information provided by the engine controller 240, generator torque limit value (Lmt) information provided by the generator controller 250, etc.

[0041] For example, if the engine driving mode is determined to be engine partial load or engine full load, the engine required torque determination unit 213 transmits a signal determining permission for fuel injection to the engine in conjunction with the current engine RPM (e.g., 50 to 900 RPM) to the engine controller 240, and also transmits an engine torque command to the engine controller 240 so that the engine torque and RPM reach the target torque and RPM of the engine and are adjusted to be less than the generator torque limit value. Alternatively, if the engine drive mode is determined to be engine idle, the engine required torque determination unit 213 transmits a signal to the engine controller 240 to determine whether fuel injection is permitted for the engine in conjunction with the current engine RPM (e.g., 50 to 900 RPM), and also transmits a catalyst heating (CH) permission signal to the engine controller 240.

[0042] Alternatively, if the engine driving mode is determined to be engine passive run, the engine required torque determination unit 213 transmits an engine self-diagnosis permission signal to the engine controller 240 in conjunction with the current engine RPM (e.g., 50 to 900 RPM). The generator required torque determination unit 214 is configured to determine a generator torque command based on the engine torque command information determined by the engine required torque determination unit 213, the engine target torque and RPM information calculated by the engine driving amount calculation unit 212, the generator RPM information provided by the generator controller 250, etc., and transmits the determined generator torque command to the generator controller 250.

[0043] The takeoff and landing hold request unit 215 is configured to transmit a takeoff hold signal to the flight controller 220 if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if the catalyst is heated during engine idle, and to transmit a landing hold signal to the flight controller 220 if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if the engine RPM is below a reference value and there is no fuel injection.

[0044] Hereinafter, a powertrain control method for a vertical take-off and landing (VTOL) vehicle having the above-described configuration will be described. The control method of the present invention may include determining a current flight stage of the VTOL vehicle, determining an engine drive mode, calculating an engine drive amount, determining an engine required torque, and determining a generator required torque in sequence according to the determined flight stage, thereby driving the engine, and driving the generator by driving the engine and charging the generated power of the generator to a battery.

[0045] 6 is a flowchart showing a powertrain control method for a vertical take-off and landing aircraft in a take-off standby state according to the present invention. First, the current flight stage of the vertical take-off and landing aircraft is determined, and the current flight stage can be determined to be a take-off preparation state. For example, if the flight controller 220 provides the main controller 210 with current flight stage information, which is one of stages (1) to (11) representing the entire flight process of the vertical take-off and landing aircraft, the main controller 210 can determine the current flight stage to be the aforementioned stage (1), which is prepare for take-off.

[0046] If the current flight stage is determined to be a takeoff preparation stage (S101), the main controller 210 sequentially performs an engine driving mode determination step (S102), an engine driving amount calculation step (S103), an engine required torque determination step (S104), and a generator required torque determination step (S105). In addition, to determine whether takeoff standby is possible, the main controller 210 sequentially performs a step of comparing the battery SOC with a reference value (A) (S106), a step of comparing the battery discharge limit value (DchLmt) with a reference value (B) (S107), and a step of determining whether catalyst heating (CH) is complete (S108). Therefore, if the comparison result in step S106 shows that the battery SOC is below the reference value, if the comparison result in step S107 shows that the battery discharge limit value is below the reference value, or if the determination result in step S108 shows that catalyst heating is being performed continuously, a takeoff standby request signal is transmitted from the takeoff and landing standby request unit 215 of the main controller 210 to the flight controller 220 (S109), and the VTOL aircraft is maintained in a takeoff standby state until the battery SOC is fully charged and catalyst heating is completed.

[0047] Here, if the catalyst temperature is below a reference value, it is determined that catalyst heating is being performed continuously while the engine is idling, and if the catalyst temperature is above the reference value, it is determined that catalyst heating has been completed. Meanwhile, in the engine driving mode determination step (S102), the engine driving mode is determined to be a partial engine load or a full engine load that can assist battery charging, and in the engine driving amount calculation step (S103), the engine target torque and the engine target RPM for battery charging are calculated, and in the engine required torque determination step (S104), fuel injection permission for the engine and an engine torque command are determined, so that the engine can be driven continuously for battery charging.

[0048] Therefore, by driving the generator through engine driving and charging the battery with the power generated by the generator, the battery SOC can be charged to its maximum value. Furthermore, if a catalyst heating (CH) request signal is received when determining the engine driving mode in engine driving mode determination step S102, the engine driving mode is determined to be engine idle so that the catalyst is heated to a certain temperature or higher before takeoff. If the catalyst temperature exceeds a reference value, it can be determined that catalyst heating is complete. Therefore, if the battery SOC exceeds the reference value, the battery discharge limit value exceeds the reference value, and it is determined that catalyst heating is complete, the main controller 210 transmits a takeoff permission signal to the flight controller 220 (S110), and the VTOL aircraft proceeds to the takeoff phase.

[0049] 7 is a flowchart showing a powertrain control method from the vertical takeoff phase to the acceleration phase of a vertical takeoff and landing (VTOL) vehicle according to the present invention. During the entire flight process of a VTOL vehicle, from (2) the vertical takeoff phase (climbing vertically to a certain height), to (3) the hovering phase (pausing temporarily to prepare for horizontal flight), (4) the transition phase (moving to a higher altitude for horizontal flight), and (5) the acceleration phase (accelerating to a speed for horizontal flight), the rotor drive motor, which uses battery power, requires the greatest output. Therefore, the engine output is used to continuously assist in charging the battery.

[0050] To this end, if the current flight stage is determined to be one of stages (2) to (5) (S201), the main controller 210 again performs the engine driving mode determination step (S202), the engine driving amount calculation step (S203), the engine required torque determination step (S204), and the generator required torque determination step (S205). Thus, the engine driving mode determination step (S202) determines the engine driving mode to be a partial engine load or a full engine load that can assist battery charging, the engine driving amount calculation step (S203) calculates the engine target torque and the engine target RPM for battery charging, and the engine required torque determination step (S204) determines fuel injection permission and an engine torque command for the engine. As a result, the engine driving drives the generator, and the battery is charged with the generated power of the generator, thereby maintaining the battery SOC above a reference value.

[0051] Meanwhile, during the entire flight process of a vertical take-off and landing (VTOL) vehicle, (6) during the cruising phase, in which the aircraft cruises to the destination at a constant speed, the motor power requirement is not large due to the lift of the fixed wing, so engine self-diagnosis can be performed. Engine self-diagnosis can also be performed during the take-off waiting phase. To this end, when an oxygen sensor diagnosis request signal for engine self-diagnosis is provided from engine controller 240 to main controller 210, engine drive mode determiner 211 of main controller 210 determines the engine drive mode to be engine passive run, in which the engine is rotated by the drive of the generator. Therefore, when battery power is supplied to the generator to drive it, the engine rotates without ignition due to the drive of the generator, and only fresh air can be provided to the engine combustion chamber.

[0052] Therefore, when the amount of fresh air flowing into the engine is detected by an oxygen sensor installed at a predetermined position in the engine and transmitted to the main controller 210, the main controller 210 analyzes the detection signal of the oxygen sensor to determine whether the engine is lean or rich, and if the detection signal is rich, it can turn on a warning light indicating that the engine needs to be inspected.

[0053] 8 is a flowchart showing a powertrain control method for a VTOL vehicle during a cruising flight phase according to the present invention. During the entire flight process of the VTOL vehicle, even if the motor power requirement is not large due to the lift of the fixed wing during the cruising phase (6), in which the VTOL vehicle flies at a constant speed to the destination, the engine output is used to charge the battery to maintain the battery SOC above a reference value when the VTOL vehicle approaches the destination during the cruising phase.

[0054] To this end, if the current flight stage is determined to be the cruising stage (6) (S301), that is, if the current flight stage is determined to be a cruising stage approaching the destination, the main controller 210 again performs the engine driving mode determination step (S302), the engine driving amount calculation step (S303), the engine required torque determination step (S304), and the generator required torque determination step (S305). In addition, to determine whether to perform landing standby, the main controller 210 sequentially performs a step of comparing the battery SOC with a reference value (C) (S306), a step of comparing the battery discharge limit value (DchLmt) with a reference value (D) (S307), and a step of comparing the engine RPM with a reference value (E) and determining whether to perform fuel injection (S308).

[0055] Therefore, if the comparison result in step S306 indicates that the battery SOC is below the reference value, the comparison result in step S307 indicates that the battery discharge limit value is below the reference value, or the comparison and determination result in step S308 indicates that the engine RPM is below the reference value (E) or that fuel is not being injected, a landing standby request signal is transmitted from the takeoff and landing standby request unit 215 of the main controller 210 to the flight controller 220 (S309), and the vertical takeoff and landing aircraft remains in a landing standby state.

[0056] Here, the engine can be continuously driven to charge the battery through the following processes: determining the engine driving mode (S302) to be either a partial engine load or a full engine load, which can assist battery charging; calculating the engine driving amount (S303) to calculate the engine target torque and target RPM for battery charging; and determining the engine required torque (S304) to permit fuel injection and determine the engine torque command. Thus, the generator is driven by the engine, and the battery's generated power is charged, thereby charging the battery SOC to its maximum value. Therefore, if the battery SOC exceeds a reference value, the battery discharge limit value exceeds a reference value, the engine RPM for battery charging exceeds a reference value (E), and it is determined that fuel is being injected, the main controller 210 transmits a landing permission signal to the flight controller 220 (S310), and the VTOL aircraft can proceed to the landing phase.

[0057] 9 is a flowchart showing a powertrain control method for a vertical take-off and landing (VTOL) vehicle from the deceleration stage to the vertical landing completion stage according to the present invention. During the entire flight process of a VTOL vehicle, from (7) the deceleration stage where the vehicle approaches the destination and decelerates for landing, to (8) the transition stage where the vehicle moves to a higher altitude for vertical landing, (9) the hovering stage where the vehicle temporarily stops for vertical landing preparation, (10) the vertical landing stage where the vehicle descends vertically to the destination, and (11) the completion of vertical landing at the destination, the rotor drive motor output, which uses battery power, requires the greatest amount of power. Therefore, the engine output is used to continuously supplement battery charging.

[0058] To this end, if the current flight stage is determined to be one of stages (7) to (11) (S401), the main controller 210 again performs the engine driving mode determination step (S402), the engine driving amount calculation step (S403), the engine required torque determination step (S404), and the generator required torque determination step (S405). Therefore, in the engine driving mode determination step (S402), the engine driving mode is determined to be a partial engine load or a full engine load that can assist battery charging. In the engine driving amount calculation step (S403), the target engine torque and target engine RPM for battery charging are calculated. In the engine demand torque determination step (S404), fuel injection permission for the engine and an engine torque command are determined. Through these processes, the engine can be driven continuously to charge the battery. As a result, the generator is driven by the engine driving, and the battery is charged with the generated power of the generator, thereby maintaining the battery SOC above a reference value.

[0059] As described above, according to the present invention, the battery SOC can be maintained above a certain level at each flight stage of a vertical take-off and landing (VTOL) aircraft for urban air mobility, allowing the VTOL aircraft to fly stably, reducing exhaust gas emissions by catalyst heating before take-off, and enabling engine self-diagnosis upon request for oxygen sensor diagnosis. [Explanation of symbols]

[0060] 10 motors 20 Engine 30 Generator 40 Battery 100 flying objects 110 Aircraft Section 120 Wings 130 rotor 200 control device 210 Main Controller 211 Engine drive mode determination unit 212 Engine driving amount calculation unit 213 Engine required torque determination unit 214 Generator required torque determination unit 215 Takeoff and Landing Standby Request Department 220 Flight Controller 230 Battery Controller 240 Engine Controller 250 Generator Controller

Claims

1. a rotor drive motor coupled to the rotor of the vertical take-off and landing aircraft so as to be capable of transmitting power; a battery connected to the rotor driving motor so as to be able to supply power; a generator connected to the battery so as to be chargeable and dischargeable; an engine connected to the generator so as to be capable of transmitting power; a control device that controls the operation of the engine and the generator for charging the battery and determines whether or not the vertical take-off and landing aircraft is ready for take-off and landing, The control device a main controller that controls the operation of the engine and the generator based on information provided by the flight controller, the battery controller, the engine controller, and the generator controller, and determines whether to allow takeoff or hold for takeoff or whether to allow landing or hold for landing of the vertical takeoff and landing aircraft; The main controller an engine drive mode determination unit that determines an engine drive mode to be one of an engine stop, an engine passive run, an engine idle, an engine partial load, and an engine full load; an engine driving amount calculation unit that calculates a target torque and a target RPM of the engine for charging the battery; an engine required torque determination unit that determines fuel injection permission for the engine, an engine torque command, catalyst heating permission, and engine self-diagnosis permission; a generator required torque determination unit that determines a generator torque command; a takeoff and landing holding request unit that determines takeoff and landing holding of the vertical takeoff and landing aircraft; A powertrain control system for a vertical take-off and landing aircraft, comprising:

2. The control device further a flight controller that provides motor power requirements and current flight phase information for the VTOL vehicle; a battery controller for providing battery SOC information, battery discharge limit value information, and battery charge limit value information; an engine controller that provides a catalyst heating request signal, an oxygen sensor diagnosis request signal, and current engine RPM information; a generator controller providing generator torque limit and generator RPM information; 2. The powertrain control system of claim 1, further comprising:

3. The engine drive mode determination unit 2. The powertrain control system of claim 1, wherein the engine drive mode is determined to be a partial engine load or a full engine load so that the engine output can assist battery charging if the motor required power is above a certain level.

4. The engine drive mode determination unit 2. The powertrain control system of claim 1, wherein the engine drive mode is determined to be an engine partial load or an engine full load so that the battery can be charged by driving a generator driven by the engine if it is determined that the battery SOC is equal to or lower than a reference value or a battery discharge limit value is equal to or lower than a reference value.

5. The engine drive mode determination unit 2. The powertrain control system of claim 1, wherein the engine drive mode is determined to be engine idle so that the catalyst is heated to a predetermined temperature or higher before takeoff when a catalyst heating request signal is received.

6. The engine drive mode determination unit 2. The powertrain control system of claim 1, wherein the engine drive mode is determined to be engine passive run when an oxygen sensor diagnosis request signal for engine self-diagnosis is received.

7. The engine required torque determination unit 2. The powertrain control system of claim 1, wherein if the engine drive mode is determined to be engine partial load or engine full load, the powertrain control system is configured to transmit to the engine controller a signal for determining permission to inject fuel into the engine in conjunction with a current engine RPM, and an engine torque command for adjusting the engine torque and RPM to be less than a generator torque limit value while the engine torque and RPM reach target engine torque and RPM.

8. The engine required torque determination unit 2. The powertrain control system of claim 1, wherein if the engine drive mode is determined to be engine idle, a signal determining permission to inject fuel into the engine and a catalyst heating permission signal are transmitted to the engine controller in conjunction with a current engine RPM.

9. The engine required torque determination unit 2. The powertrain control system of claim 1, wherein if the engine drive mode is determined to be the engine passive run, the powertrain control system is configured to transmit an engine self-diagnosis enable signal to the engine controller in conjunction with a current engine RPM.

10. The takeoff and landing waiting request unit 2. The powertrain control system of claim 1, wherein the powertrain control system is configured to transmit a takeoff standby signal to the flight controller if the battery SOC is below a reference value, if the battery discharge limit value is below a reference value, or if catalyst heating is being performed while the engine is idle.

11. The takeoff and landing waiting request unit 2. The powertrain control system of claim 1, wherein the powertrain control system is configured to transmit a landing hold signal to the flight controller when the battery SOC is below a reference value, when the battery discharge limit value is below a reference value, or when the engine RPM is below a reference value but there is no fuel injection.

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