Propulsion system, propulsion control device, and propulsion control program

Abstract

In the present invention, a motor device (60) has a motor (61) and a motor housing (70). The motor housing (70) has a motor opening part (72), a motor lid part (75), a motor lid holding part (76), and a motor holding drive part (77). An inverter device (80) has an inverter high-voltage part (86), an inverter low-voltage part (87), and an inverter housing (90). The inverter housing (90) has an inverter opening part (92), an inverter lid part (95), an inverter lid holding part (96), and an inverter holding drive part (97). If a high-temperature abnormality occurs in a drive heat generation part such as the motor (61), the inverter high-voltage part (86), or the inverter low-voltage part (87), a flight control device (40) drives the holding drive parts (77, 97) such that holding of the lid parts (75, 95) by the lid holding parts (76, 96) is released.

Description

Propulsion system, propulsion control device, and propulsion control program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2023-116161 filed in Japan on July 14, 2023, and the contents of the original application are incorporated by reference in their entirety.

[0002] The disclosure in this specification relates to a propulsion system, a propulsion control device, and a propulsion control program.

[0003] Patent Document 1 describes an electric vehicle. This electric vehicle is equipped with a motor, an inverter, a motor control device, and a cooler. The cooler is capable of cooling the inverter. If an abnormality occurs in the cooler, the motor control device lowers the upper limit of the inverter's output. Patent Document 1 states that this makes it possible to prevent the inverter and motor from stopping due to the inverter temperature becoming too high, even if an abnormality occurs in the cooler.

[0004] Japanese Patent Application Laid-Open No. 2020-137157

[0005] However, in the above-mentioned Patent Document 1, the upper limit of the inverter output is lowered to suppress the temperature rise of the inverter, which is thought to reduce the degree of freedom regarding the driving of the motor. Therefore, when a mobile object such as an electric vehicle is moving, there is a concern that if the degree of freedom regarding the driving of the motor is reduced, it will become difficult to move the mobile object to a safe state.

[0006] A main object of the present disclosure is to provide a propulsion system, a propulsion control device, and a propulsion control program that can ensure the safety of a moving body even if an abnormality occurs in the propulsion system.

[0007] The multiple aspects disclosed in this specification employ different technical means to achieve their respective objectives. Furthermore, the reference symbols in parentheses in the claims and this section are merely examples showing the correspondence between specific means described in the embodiments below as one aspect, and do not limit the technical scope.

[0008] In order to achieve the above object, the disclosed aspect is a propulsion system for propelling a moving body, comprising: a motor that drives the moving body to propel it; a drive heat-generating section that generates heat as the motor is driven; a drive housing that houses the drive heat-generating section; a housing lid section that is arranged to be able to open the housing opening of the drive housing; a lid holding section that holds the housing lid section in a closed state that covers the housing opening; and a lid release section that releases the hold of the housing lid section by the lid holding section when a high temperature abnormality occurs, including when the temperature of the drive heat-generating section reaches a predetermined temperature.

[0009] According to the above aspect, when an abnormally high temperature occurs in the drive heat-generating component, the lid holder releases the hold of the housing lid, thereby opening the housing lid. With this configuration, opening the housing lid allows the drive heat-generating component to be directly cooled by outside air flowing in through the housing opening. This prevents the motor from immediately stopping due to an abnormally high temperature in the drive heat-generating component, and prevents the degree of freedom in driving the motor from being reduced due to an abnormally high temperature in the drive heat-generating component. Therefore, even if an abnormally high temperature occurs in the drive heat-generating component, it is possible to continue driving the motor until the moving body is evacuated to a safe state. As described above, the safety of the moving body can be ensured even if an abnormality occurs in the propulsion system.

[0010] The disclosed aspect is a propulsion control device that controls a propulsion system having a motor that drives to propel a moving body, a drive heat-generating section that generates heat as the motor is driven, a drive housing that houses the drive heat-generating section, a housing lid section that is configured to be able to open the housing opening of the drive housing, a lid holding section that holds the housing lid section in a closed state that covers the housing opening, and a holding drive section that drives to displace the lid holding section, and is equipped with a high temperature determination section that determines whether a high temperature abnormality has occurred, including the temperature of the drive heat-generating section reaching a predetermined temperature, and a release execution section that, when a high temperature abnormality has occurred, drives the holding drive section to transition the lid holding section to a release state in which it releases its hold on the housing lid section.

[0011] According to the above propulsion control device, similar to the above propulsion system, the safety of the flying vehicle can be ensured even if an abnormality occurs in the propulsion system.

[0012] The disclosed aspect is a propulsion control program for controlling a propulsion system having a motor that drives to propel a moving body, a drive heat-generating part that generates heat as the motor is driven, a drive housing that houses the drive heat-generating part, a housing lid that is configured to be able to open the housing opening of the drive housing, a lid holding part that holds the housing lid in a closed state that covers the housing opening, and a holding drive part that drives to displace the lid holding part, wherein the propulsion control program causes at least one processing unit to determine whether a high temperature abnormality has occurred, including the temperature of the drive heat-generating part reaching a predetermined temperature, and when a high temperature abnormality has occurred, drives the holding drive part to transition the lid holding part to a release state in which it releases its hold on the housing lid part.

[0013] According to the above propulsion control program, similar to the above propulsion system, the safety of the flying vehicle can be ensured even if an abnormality occurs in the propulsion system.

[0014] 1 is a diagram showing the configuration of an eVTOL in a first embodiment. FIG. 2 is a block diagram showing the electrical configuration of a propulsion system. FIG. 3 is a schematic vertical cross-sectional view of an inverter housing when the inverter lid is in a closed state. FIG. 4 is a schematic vertical cross-sectional view of an inverter housing when the inverter lid is in an open state. FIG. 5 is a flowchart showing the procedure for flight control processing. FIG. 6 is a flowchart showing the procedure for flight control processing in a second embodiment. FIG. 7 is a block diagram showing the electrical configuration of a propulsion system in a third embodiment. FIG. 8 is a schematic vertical cross-sectional view of an inverter housing when the inverter lid is in a closed state. FIG. 9 is a schematic vertical cross-sectional view of an inverter housing when the inverter lid is in an open state. FIG. 10 is a flowchart showing the procedure for flight control processing. FIG.

[0015] Hereinafter, several embodiments for carrying out the present disclosure will be described with reference to the drawings. In each embodiment, parts corresponding to matters described in the preceding embodiment will be assigned the same reference numerals, and duplicate descriptions may be omitted. In each embodiment, when only a part of the configuration is described, other previously described embodiments may be applied to the other parts of the configuration. In addition to combinations of parts that are specifically specified as being combinable in each embodiment, it is also possible to partially combine embodiments even if not specified, as long as there is no particular problem with the combination.

[0016] First Embodiment The propulsion system 30 shown in FIG. 1 is mounted on an eVTOL 10. The eVTOL 10 is an electric vertical take-off and landing aircraft. An electric vertical take-off and landing aircraft is an electric vertical take-off and landing aircraft capable of vertical take-off and landing. eVTOL is an abbreviation for electric Vertical Take-Off and Landing aircraft. The eVTOL 10 is an electric air vehicle that flies in the atmosphere and is sometimes referred to as an electric air vehicle. The eVTOL 10 is also an electric aircraft and is sometimes referred to as an electric aircraft. The eVTOL 10 is a manned air vehicle that carries a crew member. The crew member of the eVTOL 10 includes a pilot who operates or drives the vehicle. The propulsion system 30 is a system that drives the eVTOL 10 to propel it. The propulsion system 30 is sometimes referred to as a flight system.

[0017] The eVTOL 10 has an airframe 11 and a propeller 20. The airframe 11 has an airframe main body 12 and wings 13. The airframe main body 12 is the fuselage of the airframe 11 and has a shape that extends, for example, from front to back. The airframe main body 12 has a crew cabin 14 for crew members to ride in. The wings 13 extend from the airframe main body 12 and multiple wings 13 are provided on the airframe main body 12. The wings 13 are fixed wings. The multiple wings 13 include main wings, a tail, and the like.

[0018] The eVTOL 10 has a cabin. The cabin is provided inside the eVTOL 10. For example, the cabin is the internal space of the aircraft body 12 and is formed by the aircraft body 12. The cabin can be a crew cabin 14 or a cargo bay. The crew cabin 14 can be a passenger cabin or a pilot cabin. The crew cabin 14 is provided with seats for crew members to sit in. The crew cabin 14 does not have to be occupied by crew members, and may instead house cargo.

[0019] A plurality of propellers 20 are provided on the airframe 11. The eVTOL 10 is a multicopter having at least three propellers 20. For example, at least six propellers 20 are provided on the airframe 11. The propellers 20 are provided on each of the airframe body 12 and the wings 13. The propellers 20 rotate around a propeller axis. The propeller axis is, for example, the center line of the propeller 20. The propellers 20 can generate thrust and lift for the eVTOL 10. The propellers 20 are sometimes referred to as rotors or rotating blades.

[0020] The eVTOL 10 has multiple propellers 20, which makes it easier to maintain aircraft balance. Even if the propeller output of one propeller 20 unintentionally decreases, the eVTOL 10 can continue flight using the remaining propellers 20. Propeller output includes the rotation speed and torque of the propellers 20.

[0021] The propeller 20 has blades, a boss, and a propeller shaft. A plurality of blades are arranged in the circumferential direction of the propeller axis. The boss connects the plurality of blades. The propeller shaft is the rotation axis of the propeller 20 and extends from the boss along the propeller axis.

[0022] Flight modes of the eVTOL 10 include vertical takeoff, vertical landing, cruise, hovering, etc. Flight modes are sometimes referred to as flight modes. In vertical takeoff, the eVTOL 10 can take off without running. In vertical takeoff, the eVTOL 10 may ascend vertically or may ascend diagonally upward. In vertical landing, the eVTOL 10 can land without running. In vertical landing, the eVTOL 10 may descend vertically or may descend diagonally downward.

[0023] Cruising is sometimes referred to as level flight. In cruising, the eVTOL 10 may fly horizontally without moving vertically, or may fly horizontally while moving vertically. Hovering is sometimes referred to as stationary flight. In hovering, the eVTOL 10 may fly as if stationary at a predetermined position in the air, or the eVTOL 10 may deviate vertically or horizontally from the predetermined position.

[0024] The flight modes of the eVTOL 10 also include lift. In lift, the eVTOL 10 moves up and down. As a lift, the eVTOL 10 may ascend diagonally upward or descend diagonally downward. The eVTOL 10 takes off vertically by lifting upward. The eVTOL 10 lands vertically by lifting downward.

[0025] The eVTOL 10 is a tilt rotor aircraft. The eVTOL 10 has an adjustable tilt angle for the propeller 20. The eVTOL 10 can have one propeller 20 function as both a lift propeller and a cruise propeller. For example, when the eVTOL 10 lifts, the tilt angle is adjusted so that the propeller 20 functions as a lift rotor. When the eVTOL 10 cruises, the tilt angle is adjusted so that the propeller 20 functions as a cruise rotor. Note that the eVTOL 10 does not have to be a tilt rotor aircraft. For example, the eVTOL 10 may have separate propellers 20 for lift and cruise.

[0026] The eVTOL 10 has a battery 31, a distributor 32, a communication unit 34, a flight control device 40, and an EPU 50. The battery 31, distributor 32, communication unit 34, flight control device 40, and EPU 50 are included in a propulsion system 30. Note that the propulsion system 30 only needs to include at least the flight control device 40 and the EPU 50. The flight control device 40 is sometimes referred to as a flight controller.

[0027] The battery 31 is electrically connected to the EPU 50. The battery 31 is a power supply unit that supplies power to the EPU 50 and corresponds to a power supply unit. The battery 31 is a DC voltage source that applies a DC voltage to the EPU 50. The battery 31 has a rechargeable secondary battery. Examples of such secondary batteries include a lithium ion battery and a nickel-metal hydride battery. The battery 31 is capable of storing power and corresponds to a power storage device. Note that a fuel cell, a generator, or the like may be used as the power supply unit in addition to or instead of the battery 31.

[0028] The distributor 32 is electrically connected to the battery 31 and the plurality of EPUs 50. The distributor 32 distributes power from the battery 31 to the plurality of EPUs 50. The battery 31 is electrically connected to the plurality of EPUs 50 via the distributor 32. The battery 31 supplies power to the EPUs 50 via the distributor 32.

[0029] The communication unit 34 is a communication device capable of wireless communication with an external device. The external device is a device located away from the eVTOL 10. Examples of external devices include communication devices installed in external facilities on the ground and communication devices installed in other flying vehicles. Examples of external facilities include a control center and a management center. The communication unit 34 is capable of communication with the flight control device 40. The communication unit 34 is connected to the flight control device 40 so that it can communicate via wired communication. Note that the communication unit 34 may also be capable of wireless communication with the flight control device 40.

[0030] 1 and 2 , the EPU 50 is a device that drives the propeller 20 to rotate, and corresponds to a drive device. EPU is an abbreviation for Electric Propulsion Unit. The EPU 50 is sometimes referred to as an electric drive device or an electric drive system. An EPU 50 is provided for each of the multiple propellers 20. The EPUs 50 are arranged on the propellers 20 along the propeller axis. All of the multiple EPUs 50 are fixed to the airframe 11. The EPUs 50 support the propellers 20 so that they can rotate. The EPUs 50 are connected to the propellers 20. The propellers 20 are fixed to the airframe 11 via the EPUs 50.

[0031] As shown in FIG. 2 , the eVTOL 10 has a propulsion device 100. The propulsion device 100 is formed to include a propeller 20 and an EPU 50. The propulsion device 100 is a device for propelling the eVTOL 10. The propulsion device 100 causes the eVTOL 10 to fly by rotating the propeller 20. The eVTOL 10 is also a moving body that moves using the propulsion device 100. A plurality of propulsion devices 100 are provided in the eVTOL 10. One propulsion device 100 includes one propeller 20 and one EPU 50 for driving the propeller 20. Note that only the EPU 50 of the propeller 20 and the EPU 50 may be referred to as the propulsion device 100.

[0032] The EPU 50 has a motor device 60 and an inverter device 80. The motor device 60 has a motor 61 and a motor housing 70. The motor housing 70 is a housing and houses the motor 61. The motor housing 70 has a motor space 70a. The motor space 70a is the internal space of the motor housing 70.

[0033] The motor 61 is a multi-phase AC motor. The motor 61 is a multi-phase AC rotating electric machine. The motor 61 is the flight drive source for the eVTOL 10 and functions as an electric motor. The motor 61 drives and rotates the propeller 20, enabling the eVTOL 10 to fly. The motor 61 is a flight motor for flying the eVTOL 10. The EPU 50 drives and rotates the propeller 20 by driving the motor 61. A brushless motor, for example, is used as the motor 61.

[0034] The motor 61 has a motor stator 62 and a motor rotor 63. The motor 61 has the motor stator 62. The motor stator 62 is a stator and is fixed to the motor housing 70. The motor rotor 63 rotates relative to the motor stator 62. The rotation of the motor rotor 63 is sometimes referred to as the rotation of the motor 61. The motor 61 is, for example, an axial gap motor. In the motor 61, the motor stator 62 and the motor rotor 63 are aligned in the axial direction AD. The motor 61 is, for example, a double-rotor motor. The motor 61 has two motor rotors 63. In the motor 61, the two motor rotors 63 are aligned in the axial direction AD via the motor stator 62. The motor 61 has a motor shaft that rotates together with the motor rotor 63. The motor shaft is rotatably supported by the motor housing 70 or the like.

[0035] The axial direction AD is the direction in which the motor axis Cm extends. The motor axis Cm is the rotation axis of the motor rotor 63. The motor rotor 63 rotates around the motor axis Cm. The motor axis Cm is the center line of the motor rotor 63. The motor axis Cm is sometimes referred to as the rotation axis. With respect to the motor axis Cm, the axial direction AD, the circumferential direction CD, and the radial direction RD are perpendicular to one another. The outside of the radial direction RD is sometimes referred to as the radial outside or outer circumferential side. The inside of the radial direction RD is sometimes referred to as the radial inside or inner circumferential side.

[0036] The motor 61 is driven by power being supplied to the motor stator 62. The motor stator 62 has a stator coil. The stator coil is a multi-phase coil. The stator coil forms an armature. When power is supplied to the motor stator 62, current flows through the stator coil, causing the motor rotor 63 to rotate. The motor rotor 63 has a rotor magnet such as a permanent magnet. The rotor magnet forms a magnetic field. Driving the motor 61 to rotate the motor rotor 63 is sometimes referred to as rotational driving of the motor 61. Rotational driving of the motor 61 is sometimes simply referred to as driving the motor 61.

[0037] The inverter device 80 drives the motor device 60 by supplying power to the motor device 60. The inverter device 80 is a drive unit for driving the motor 61 and corresponds to a motor drive unit. The inverter device 80 has an inverter circuit 85 and an inverter housing 90. The inverter circuit 85 converts the power supplied to the motor 61. The inverter circuit 85 may also be referred to as an inverter, a power conversion unit, or a control circuit. The inverter circuit 85 performs power conversion for each of the multiple phases. The motor 61 is driven in accordance with the voltage and current supplied from the inverter circuit 85.

[0038] The inverter housing 90 is a housing that houses the inverter circuit 85 and an inverter control unit 81 (described later). The inverter housing 90 has an inverter space 90a. The inverter space 90a is the internal space of the inverter housing 90.

[0039] The inverter device 80 has an inverter control unit 81. The inverter control unit 81 performs motor control via an inverter circuit 85. The motor control is control for driving the motor 61. The inverter control unit 81 also performs propulsion control. The propulsion control is control for driving the propulsion device 100. The propulsion control includes motor control. The propulsion control is also control for controlling the EPU 50, and is sometimes referred to as EPU control.

[0040] The inverter control unit 81 has, for example, an ECU. ECU is an abbreviation for Electronic Control Unit. The inverter control unit 81 has a processor 82, a memory 83, and a program 84. The inverter control unit 81 is mainly configured with a computer. This computer has the processor 82, memory 83, an input / output interface, a bus connecting these, etc. The memory 83 stores the program 84. The program 84 is a program for performing propulsion control. The program 84 corresponds to a propulsion control program.

[0041] The processor 82 is hardware for arithmetic processing coupled to the memory 83. The processor 82 executes various processes by accessing the memory 83. The memory 83 is a storage medium that stores a control program and the like. For example, the memory 83 is a non-transitory tangible storage medium that non-temporarily stores computer-readable programs and data. The non-transitory tangible storage medium is a non-transitory tangible storage medium, and is realized by a semiconductor memory, a magnetic disk, or the like. The program 84 includes computer-readable instructions that cause the processor 82 to execute various functions. The processor 82 is a processing unit that executes predetermined processes by executing the instructions included in the program 84.

[0042] The inverter control unit 81 controls the motor according to the required output. The required output is the motor output required of the inverter control unit 81. The required output includes, for example, the required torque required for the output torque. The required output is included in a command signal output by the flight control device 40 to the inverter control unit 81. The inverter control unit 81 adjusts the motor output according to the required output. The required output and required torque are sometimes referred to as target output and target torque. Note that torque, current, voltage, motor rotation speed, etc. may also be used as the motor output.

[0043] The inverter control unit 81 controls the motor using command signals from the flight control device 40 and detection signals from various sensors. The various sensors are communicatively connected to the inverter control unit 81. The various sensors include a motor sensor and an inverter sensor. The battery sensor is a sensor provided in the motor device 60. The inverter sensor is a sensor provided in the inverter device 80.

[0044] The flight control device 40 is communicatively connected to the inverter control unit 81. The flight control device 40 and the inverter control unit 81 may be capable of wireless communication. The flight control device 40 performs overall control to coordinate the drive of the multiple propulsion devices 100. The overall control coordinates the propulsion controls performed by each of the multiple inverter control units 81. The flight control device 40 performs flight control. Flight control is control for flying the eVTOL 10. As flight control, the flight control device 40 controls the propulsion system 30 and the EPU 50. Flight control is also control for propelling the eVTOL 10, and is sometimes referred to as propulsion control. The flight control device 40 corresponds to a propulsion control device.

[0045] The flight control device 40 has, for example, an ECU. The flight control device 40 has a processor 42, a memory 43, and a program 44. The flight control device 40 is mainly composed of a computer. This computer has the processor 42, the memory 43, an input / output interface, a bus connecting these, etc. The memory 43 stores the program 44. The program 44 is a program for performing flight control.

[0046] The processor 42 is hardware for arithmetic processing coupled to the memory 43. The processor 42 executes various processes by accessing the memory 43. The memory 43 is a storage medium that stores a control program and the like. For example, the memory 43 is a non-transient tangible storage medium that non-temporarily stores computer-readable programs and data. The program 44 includes computer-readable instructions that cause the processor 42 to execute various functions. The processor 42 is a processing unit that executes predetermined processes by executing the instructions included in the program 44.

[0047] The flight control device 40 outputs information necessary for propulsion control to the inverter control unit 81. The flight control device 40 performs motor control via the inverter control unit 81. The flight control device 40 is a host ECU for the inverter control unit 81. The flight control device 40 individually controls the multiple propulsion devices 100 according to the flight mode of the eVTOL 10, etc. The flight control device 40 can individually adjust the output of the propulsion devices 100 for each propulsion device 100. For example, the flight control device 40 outputs a required output to each of the multiple propulsion devices 100. The required output is the output required of the propulsion device 100. An example of the required output is the required torque required of the motor 61. Note that torque, current, voltage, motor rotation speed, etc. may also be used as the required output.

[0048] The flight control device 40 performs flight control in response to the flight state of the eVTOL 10 and detection signals from various sensors. The flight state of the eVTOL 10 includes the flight mode and the flight attitude of the eVTOL 10. Various sensors are communicatively connected to the flight control device 40. The various sensors include an EPU sensor and a battery sensor. The EPU sensor is a sensor provided in the EPU 50. The battery sensor is a sensor provided in the battery 31, such as a temperature sensor.

[0049] The EPU sensors include a temperature sensor 55 and a current sensor 56. The temperature sensor 55 and the current sensor 56 are provided in each of the multiple propulsion devices 100. The temperature sensor 55 is provided in the EPU 50. The temperature sensor 55 is provided in the motor device 60 and the inverter device 80. The temperature sensor 55 detects the temperature of the EPU 50. The temperature of the EPU 50 includes the temperature of the motor device 60 and the temperature of the inverter device 80. For example, the temperature sensor 55 detects the temperature of the motor stator 62 and the temperature of the motor rotor 63 as the temperature of the motor device 60. The temperature sensor 55 also detects the temperature of the part forming the inverter circuit 85 and the part forming the inverter control unit 81 as the temperature of the inverter device 80. At least one temperature sensor 55 is provided in the EPU 50.

[0050] The temperature sensor 55 is communicatively connected to the flight control device 40. The temperature sensor 55 outputs a detection signal corresponding to the temperature of the EPU 50 to the flight control device 40. The flight control device 40 calculates the EPU temperature Tepu using the detection signal from the temperature sensor 55. The EPU temperature Tepu is the temperature of the EPU 50.

[0051] The current sensor 56 is provided in the EPU 50. The current sensor 56 is provided in the motor device 60 and the inverter device 80. The current sensor 56 detects the motor current. The motor current is the current flowing through the motor 61. For example, the motor current is the current flowing through the motor coil. The current sensor 56 is communicatively connected to the flight control device 40. The current sensor 56 outputs a detection signal corresponding to the current flowing through the motor 61 to the flight control device 40. The flight control device 40 calculates the motor current using the detection signal from the current sensor 56.

[0052] The temperature sensor 55 and the current sensor 56 may be communicatively connected to the inverter control unit 81. In this configuration, the detection signals of the temperature sensor 55 and the current sensor 56 may be input to the flight control device 40 via the inverter control unit 81. In this configuration, the inverter control unit 81 may also calculate the EPU temperature Tepu and the motor current using the detection signals of the temperature sensor 55 and the current sensor 56, and output a signal including the EPU temperature Tepu and the motor current to the flight control device 40.

[0053] In this embodiment, the propulsion device 100 has a plurality of inverter devices 80. For example, the propulsion device 100 has a first inverter device 801 and a second inverter device 802 as the inverter devices 80.

[0054] In the propulsion device 100, both inverter devices 801 and 802 control the motor 61. In the inverter devices 801 and 802, each inverter circuit 85 supplies power to the motor stator 62. In the inverter devices 801 and 802, each inverter control unit 81 controls the motor. The motor 61 is a 2×n-phase motor, where n is a natural number. One of the inverter devices 801 and 802 drives the n-phase motor, and the other drives the remaining n-phase motor. For example, the motor 61 has 2×n-phase coils as motor coils. In the inverter devices 801 and 802, one inverter circuit 85 supplies power to the n-phase coil, and the other inverter circuit 85 supplies power to the remaining n-phase coils.

[0055] 2, the motor device 60 is shown as MOTU, the motor stator 62 as STA, and the motor rotor 63 as ROT. The inverter device 80 is shown as MCU, the inverter circuit 85 as INV, and the inverter control unit 81 as ICD. The processor 82 is shown as PRO, the memory 83 as MEM, and the program 84 as PG. The flight control device 40 is shown as FCD, the processor 42 as PRO, the memory 43 as MEM, and the program 44 as PG.

[0056] The inverter device 80 has an inverter high voltage section 86 and an inverter low voltage section 87. The inverter high voltage section 86 is a portion or component of the inverter device 80 to which a drive voltage is applied. The drive voltage is a voltage for driving the motor 61. For example, the drive voltage is applied as a high voltage to the inverter circuit 85. The drive voltage is a voltage higher than a control voltage, which will be described later. The drive voltage is a voltage applied to the inverter high voltage section 86 in conjunction with the supply of power from the battery 31 to the motor 61. The drive voltage is applied to the motor coil, etc., via the inverter circuit 85.

[0057] Inverter high voltage section 86 is a portion of inverter device 80 through which current flows in response to application of a drive voltage. Inverter high voltage section 86 includes high voltage wiring such as bus bars that form a current path to inverter circuit 85, terminal components to which the high voltage wiring is connected, semiconductor components that form inverter circuit 85, and capacitor components connected to inverter circuit 85.

[0058] The inverter low voltage section 87 is a portion or component of the inverter device 80 to which a control voltage is applied. The control voltage is a voltage for controlling the drive of the motor 61. For example, the control voltage is applied as a low voltage to the inverter control unit 81. The inverter low voltage section 87 includes electronic components such as a circuit board that forms the inverter control unit 81, low voltage wiring such as communication lines, terminal components to which the low voltage wiring is connected, and sensor components that form various sensors. The inverter low voltage section 87 is a portion of the inverter device 80 that controls the drive of the motor 61. The inverter low voltage section 87 corresponds to a control circuit section.

[0059] In the propulsion device 100, at least a portion of the inverter device 80 generates heat as the motor 61 is driven. At least a portion of the inverter device 80 corresponds to a drive heat-generating portion that generates heat as the motor 61 is driven. The drive heat-generating portion includes an inverter high voltage portion 86 and an inverter low voltage portion 87. In the inverter device 80, the inverter high voltage portion 86 and the inverter low voltage portion 87 generate heat as a current flows through them. In the inverter device 80, the inverter high voltage portion 86 is more likely to generate more heat as the motor current increases.

[0060] The driving heat generating parts include the parts that form the inverter circuit 85 and the parts that form the inverter control unit 81 in the inverter device 80. The driving heat generating parts include the parts in the inverter device 80 that are most likely to generate heat, the parts that are most likely to become hot, and the parts that are most susceptible to heat.

[0061] In inverter device 80, at least a part of inverter high voltage section 86 and at least a part of inverter low voltage section 87 may generate heat as motor 61 is driven. In this configuration, at least a part of inverter high voltage section 86 and at least a part of inverter low voltage section 87 correspond to drive heat generating sections.

[0062] The inverter housing 90 accommodates the inverter high-voltage section 86 and the inverter low-voltage section 87 as drive heat-generating sections. The inverter housing 90 corresponds to a drive housing. The inverter housing 90 has an inverter outer wall 91. The inverter outer wall 91 forms the outer surface and the inner surface of the inverter housing 90. The inverter outer wall 91 is made of a metal material or the like. The inverter outer wall 91 accommodates the inverter high-voltage section 86 and the inverter low-voltage section 87.

[0063] The inverter device 80 has an inverter vent 93 and an inverter vent filter 93a. The inverter vent 93 is provided on the outer surface of the inverter outer wall 91. The inverter vent 93 is formed by a vent hole in the inverter outer wall 91. The vent hole penetrates the inverter outer wall 91 in the radial direction RD and the axial direction AD. The inverter vent 93 opens the inverter space 90a to the outside of the inverter outer wall 91. In the inverter device 80, the inverter space 90a is ventilated through the inverter vent 93. The inverter vent 93 corresponds to a housing vent.

[0064] A plurality of inverter vents 93 are provided in the inverter device 80. For example, two inverter vents 93 are arranged side by side in the circumferential direction CD or the axial direction AD through at least one of the inverter high-voltage section 86 and the inverter low-voltage section 87. In this configuration, when outside air flows into the inverter space 90a through at least one inverter vent 93 and flows out of the inverter housing 90 through another inverter vent 93, heat from the inverter high-voltage section 86 and the inverter low-voltage section 87 is easily transferred to the outside air. The outside air is a gas such as air. The gas in the inverter space 90a flows out of the inverter vent 93 together with heat to the outside, thereby dissipating heat from the inverter high-voltage section 86 and the inverter low-voltage section 87.

[0065] The inverter air filter 93a prevents foreign matter such as water and dust from entering the inverter space 90a through the inverter air vents 93. The inverter air filter 93a corresponds to a foreign matter regulating unit. The inverter air filter 93a is formed in a sheet shape and is fixed to the inverter outer wall 91 while covering the inverter air vents 93. The inverter air filter 93a is fixed to the outer surface and inner surface of the inverter outer wall 91. An inverter air filter 93a is provided for each of the multiple inverter air vents 93.

[0066] An inverter opening 92 is provided in the inverter outer wall 91. The inverter opening 92 is an opening formed in the inverter outer wall 91. The inverter opening 92 is provided at a position facing at least a portion of the inverter high-voltage section 86 and at least a portion of the inverter low-voltage section 87. That is, the inverter opening 92 is provided at a position that allows at least a portion of the inverter high-voltage section 86 and at least a portion of the inverter low-voltage section 87 to be exposed to the outside of the inverter housing 90. For example, the inverter opening 92 is provided at a position aligned with at least a portion of the inverter high-voltage section 86 and at least a portion of the inverter low-voltage section 87 in the radial direction RD. Note that the inverter opening 92 may be provided at a position offset in the axial direction AD from the inverter high-voltage section 86 and the inverter low-voltage section 87. The inverter opening 92 communicates with the inverter space 90a. The opening area of ​​the inverter opening 92 is larger than the opening area of ​​the inverter vent 93. The inverter opening 92 corresponds to a housing opening.

[0067] The inverter opening 92 is aligned with the inverter air vent 93 and the inverter air filter 93a along the outer surface of the inverter outer wall 91. The inverter opening 92 is provided at a position away from the inverter air vent 93 and the inverter air filter 93a in the direction in which the outer surface of the inverter outer wall 91 extends. The inverter air filter 93a does not cover the inverter opening 92.

[0068] A plurality of inverter openings 92 are provided in the inverter outer wall 91. The plurality of inverter openings 92 include a first inverter opening 921 and a second inverter opening 922. The first inverter opening 921 and the second inverter opening 922 are aligned in the radial direction RD across at least one of the inverter high voltage section 86 and the inverter low voltage section 87. For example, the first inverter opening 921 and the second inverter opening 922 are aligned in the radial direction RD across the motor axis Cm. The first inverter opening 921 corresponds to the first opening, and the second inverter opening 922 corresponds to the second opening.

[0069] 2 and 3 , the inverter device 80 has an inverter lid portion 95, an inverter lid holding portion 96, an inverter holding and driving portion 97, and an inverter lid housing portion 98. The inverter lid portion 95, the inverter lid holding portion 96, the inverter holding and driving portion 97, and the inverter lid housing portion 98 are provided for the inverter opening 92. For example, the inverter lid portion 95, the inverter lid holding portion 96, the inverter holding and driving portion 97, and the inverter lid housing portion 98 are provided for the first inverter opening 921 and the second inverter opening 922, respectively.

[0070] The inverter lid 95 is a lid that covers the inverter opening 92. The inverter lid 95 is formed of a metal material or the like. The inverter lid 95 can open the inverter opening 92. The inverter lid 95 can be shifted between an open state in which the inverter opening 92 is open and a closed state in which the inverter opening 92 is closed. The inverter lid 95 corresponds to a housing lid.

[0071] The inverter lid holding portion 96 holds the inverter lid portion 95 in a closed state. The inverter lid holding portion 96 is formed of a metal material or the like. As shown in FIGS. 3 and 4 , the inverter lid holding portion 96 is displaceable between a holding position P1 and a release position P2. When the inverter lid holding portion 96 is in the holding position P1, it holds the inverter lid portion 95 in a closed state (see FIG. 3 ). When the inverter lid holding portion 96 is displaced to the release position P2, it transitions the inverter lid portion 95 to an open state (see FIG. 4 ). The release position P2 is a position where the inverter lid holding portion 96 releases its hold on the inverter lid portion 95.

[0072] The inverter lid holding portion 96 is in a holding state when it is in the holding position P1. The inverter lid holding portion 96 is in a released state when it is in the released position P2. The inverter lid holding portion 96 is capable of transitioning between a holding state and a released state. The released state is a state in which the inverter lid holding portion 96 releases the holding of the inverter lid portion 95. The inverter lid holding portion 96 corresponds to a lid holding portion.

[0073] The inverter lid holding portion 96 detachably fixes the inverter lid portion 95 to the inverter outer wall 91. When the inverter lid holding portion 96 is in the holding position P1, the inverter lid portion 95 is fixed to the inverter outer wall 91 by the inverter lid holding portion 96 and is in a closed state. When the inverter lid holding portion 96 is in the release position P2, the inverter lid portion 95 is released from the inverter outer wall 91 and is in an open state. The inverter lid holding portion 96 corresponds to a lid holding portion.

[0074] When the inverter lid 95 is in the open position, at least a portion of the inverter high-voltage section 86 and at least a portion of the inverter low-voltage section 87 are exposed to the outside of the inverter housing 90 through the inverter opening 92. In this case, the inverter opening 92 ventilates the inverter space 90a, making it easier for heat from the inverter high-voltage section 86 and the inverter low-voltage section 87 to be released to the outside through the inverter opening 92. The heat dissipation effect of the inverter opening 92 is greater than that of the inverter air vent 93. This is because the inverter opening 92 is configured such that the amount of airflow through it is likely to be greater than the amount of airflow through the inverter air vent 93. This configuration includes the fact that the opening area of ​​the inverter opening 92 is larger than the opening area of ​​the inverter air vent 93 and that no inverter air filter 93a is provided in the inverter opening 92.

[0075] When the inverter lid 95 is open at both the first inverter opening 921 and the second inverter opening 922, ventilation of the inverter space 90a is easier than when only one of the inverter lids 95 is open. For example, outside air is more likely to flow in through one of the inverter openings 921, 922 and then flow out the other through the inverter space 90a. In other words, a path for outside air is more likely to be created inside the inverter housing 90.

[0076] The inverter holding drive unit 97 is a drive unit for opening the inverter lid unit 95. The inverter holding drive unit 97 includes an actuator such as an electric motor. The inverter holding drive unit 97 is fixed to the inverter housing 90. The inverter holding drive unit 97 drives the inverter lid holding unit 96 to displace it. The inverter holding drive unit 97 moves the inverter lid unit 95 from the closed state to the open state by displacing the inverter lid holding unit 96 from the holding position P1 to the release position P2. The inverter holding drive unit 97 corresponds to the holding drive unit.

[0077] The inverter hold drive unit 97 is communicatively connected to the flight control device 40. The inverter hold drive unit 97 drives in response to signals from the flight control device 40. The inverter hold drive unit 97 may also be communicatively connected to the inverter control unit 81. In this configuration, signals from the flight control device 40 may be input to the flight control device 40 via the inverter control unit 81.

[0078] The inverter lid accommodating portion 98 is provided on the outside of the inverter outer wall 91. The inverter lid accommodating portion 98 is capable of accommodating the inverter lid 95 that has been detached from the inverter outer wall 91. The inverter lid accommodating portion 98 has a lid accommodating opening 98a. The lid accommodating opening 98a is an opening that exposes the internal space of the inverter lid accommodating portion 98. When the inverter lid 95 shifts to the open state, it detaches from the inverter outer wall 91 and enters the lid accommodating opening 98a to be accommodated in the inverter lid accommodating portion 98.

[0079] In the propulsion device 100, a propeller wind F1 is generated as the propeller 20 rotates. The propeller wind F1 is a flow of gas, such as outside air, flowing in the axial direction AD. The inverter lid housing 98 is provided on the downwind side of the propeller wind F1 with respect to the inverter lid 95 in the closed state. The inverter lid housing 98 is aligned with the inverter lid 95 in the axial direction AD. The lid housing opening 98a is open toward the upwind side of the propeller wind F1. In other words, the lid housing opening 98a is open toward the inverter lid 95. When the inverter lid 95 is opened in a situation in which a propeller wind F1 is generated as the eVTOL 10 is flying, for example, the inverter lid 95 is pushed toward the downwind side by the propeller wind F1 and is housed in the inverter lid housing 98 through the lid housing opening 98a.

[0080] As shown in Figure 4, when the inverter lid 95 is open, outside air tends to flow into the inverter space 90a as cooling air F2 from the inverter opening 92. In the inverter space 90a, heat from the inverter high-voltage section 86 and the inverter low-voltage section 87 tends to be imparted to the cooling air F2. Then, the cooling air F2 to which heat has been imparted flows out from the inverter opening 92 to the outside, thereby dissipating the heat from the inverter high-voltage section 86 and the inverter low-voltage section 87 to the outside.

[0081] In Figure 2, in the propulsion device 100, at least a portion of the motor device 60 generates heat as the motor 61 is driven. At least a portion of the motor device 60 corresponds to a drive heat-generating portion that generates heat as the motor 61 is driven. The drive heat-generating portion includes the motor 61. For example, the drive heat-generating portion includes the motor stator 62 and the motor rotor 63. In the motor 61, the motor stator 62 and the motor rotor 63 generate heat as a motor current flows through the motor coil, etc. In the motor device 60, the motor 61 is likely to generate more heat as the motor current increases. The drive heat-generating portion includes the parts of the motor device 60 that are most likely to generate heat, the parts that are most likely to become hot, and the parts that are most susceptible to heat.

[0082] In the motor device 60, at least a portion of the motor 61 may generate heat as the motor 61 is driven. In this configuration, at least a portion of the motor 61 corresponds to a drive-generating heat portion. In the motor 61, at least a portion of the motor stator 62 or at least a portion of the motor rotor 63 may generate heat as the motor 61 is driven. In this configuration, at least a portion of the motor stator 62 or at least a portion of the motor rotor 63 corresponds to a drive-generating heat portion.

[0083] The motor housing 70 accommodates the motor 61 as a drive heat generating part. The motor housing 70 corresponds to a drive housing. The motor housing 70 has a motor outer wall 71. The motor outer wall 71 forms the outer and inner surfaces of the motor housing 70. The motor outer wall 71 is made of a metal material or the like. The motor outer wall 71 accommodates the motor 61.

[0084] The motor device 60 has a motor vent 73 and a motor vent filter 73a. The motor vent 73 is provided on the outer surface of the motor outer wall 71. The motor vent 73 is formed by a vent hole in the motor outer wall 71. The vent hole penetrates the motor outer wall 71 in the radial direction RD and the axial direction AD. The motor vent 73 opens the motor space 70a to the outside of the motor outer wall 71. In the motor device 60, the motor space 70a is ventilated through the motor vent 73. The motor vent 73 corresponds to a housing vent.

[0085] A plurality of motor vents 73 are provided in the motor device 60. For example, two motor vents 73 are arranged side by side in the circumferential direction CD or the axial direction AD across the motor 61. In this configuration, when outside air flows into the motor space 70a through at least one motor vent 73 and flows out of the motor housing 70 through other motor vents 73, the outside air is likely to transfer heat from the motor 61. The outside air is a gas such as air. The gas in the motor space 70a, together with the heat, flows out of the motor vents 73 to the outside, thereby dissipating heat from the motor 61.

[0086] The motor ventilation filter 73a prevents foreign matter from entering the motor space 70a through the motor ventilation openings 73. The motor ventilation filter 73a corresponds to a foreign matter regulating portion. The motor ventilation filter 73a is formed in a sheet shape and is fixed to the motor outer wall 71 while covering the motor ventilation openings 73. The motor ventilation filter 73a is fixed to the outer surface and inner surface of the motor outer wall 71. A motor ventilation filter 73a is provided for each of the multiple motor ventilation openings 73.

[0087] A motor opening 72 is provided in the motor outer wall 71. The motor opening 72 is an opening formed in the motor outer wall 71. The motor opening 72 is provided at a position facing at least a portion of the motor 61. In other words, the motor opening 72 is provided at a position that allows at least a portion of the motor 61 to be exposed to the outside of the motor housing 70. For example, the motor opening 72 is provided at a position aligned with at least a portion of the motor 61 in the radial direction RD. Note that the motor opening 72 may also be provided at a position offset in the axial direction AD from the motor 61. The motor opening 72 communicates with the motor space 70a. The opening area of ​​the motor opening 72 is larger than the opening area of ​​the motor vent 73. The motor opening 72 corresponds to a housing opening.

[0088] The motor opening 72 is aligned with the motor vent 73 and the motor vent filter 73a along the outer surface of the motor outer wall 71. The motor opening 72 is provided at a position away from the motor vent 73 and the motor vent filter 73a in the direction in which the outer surface of the motor outer wall 71 extends. The motor vent filter 73a does not cover the motor opening 72.

[0089] A plurality of motor openings 72 are provided in the motor outer wall 71. The plurality of motor openings 72 include a first motor opening 721 and a second motor opening 722. The first motor opening 721 and the second motor opening 722 are aligned in the radial direction RD across the motor 61. For example, the first motor opening 721 and the second motor opening 722 are aligned in the radial direction RD across the motor axis Cm. The first motor opening 721 corresponds to the first opening, and the second motor opening 722 corresponds to the second opening.

[0090] The motor device 60 has a motor lid portion 75, a motor lid holder 76, a motor holding / driving portion 77, and a motor lid housing portion 78. The motor lid portion 75, the motor lid holder 76, the motor holding / driving portion 77, and the motor lid housing portion 78 are provided for the motor opening 72. For example, the motor lid portion 75, the motor lid holder 76, the motor holding / driving portion 77, and the motor lid housing portion 78 are provided for the first motor opening 721 and the second motor opening 722, respectively. The configuration of the motor lid portion 75 is similar to the configuration of the inverter lid portion 95 shown in FIGS. 3 and 4 . The configuration of the motor lid portion 75 is not shown in the drawings.

[0091] The motor lid 75 is a lid that covers the motor opening 72. The motor lid 75 is formed from a metal material or the like. The motor lid 75 can open the motor opening 72. The motor lid 75 can be shifted between an open state in which the motor opening 72 is open and a closed state in which the motor opening 72 is closed. The motor lid 75 corresponds to a housing lid.

[0092] The motor lid holding portion 76 holds the motor lid portion 75 in a closed state. The motor lid holding portion 76 is formed from a metal material or the like. The motor lid holding portion 76 is displaceable between a holding position and a release position. When in the holding position, the motor lid holding portion 76 holds the motor lid portion 75 in a closed state. When the motor lid holding portion 76 is displaced to the release position, the motor lid holding portion 76 transitions the motor lid portion 75 to an open state. The release position is a position where the motor lid holding portion 76 releases the motor lid portion 75 from its hold.

[0093] The motor cover holder 76 is in a holding state when in the holding position. The motor cover holder 76 is in a released state when in the released position. The motor cover holder 76 can be moved between a holding state and a released state. The released state is a state in which the motor cover holder 76 releases the motor cover 75 from its hold. The motor cover holder 76 corresponds to the cover holder.

[0094] The motor cover holder 76 detachably fixes the motor cover 75 to the motor outer wall 71. When the motor cover holder 76 is in the holding position, the motor cover 75 is fixed to the motor outer wall 71 by the motor cover holder 76 and is in a closed state. When the motor cover holder 76 is in the release position, the motor cover 75 is released from the motor outer wall 71 and is in an open state. The motor cover holder 76 corresponds to a cover holder.

[0095] When the motor cover 75 is in the open position, at least a portion of the motor 61 is exposed to the outside of the motor housing 70 through the motor opening 72. In this case, the motor opening 72 ventilates the motor space 70a, making it easier for heat from the motor 61 to be released to the outside through the motor opening 72. The heat dissipation effect of the motor opening 72 is greater than that of the motor vent 73. This is because the motor opening 72 is configured such that the amount of airflow through it is likely to be greater than the amount of airflow through the motor vent 73. This configuration includes the fact that the opening area of ​​the motor opening 72 is larger than the opening area of ​​the motor vent 73 and that the motor opening 72 is not provided with a motor airflow filter 73a.

[0096] When the motor cover 75 is open at both the first motor opening 721 and the second motor opening 722, ventilation of the motor space 70a is easier than when only one of the motor cover 75s is open. For example, outside air is more likely to flow in through one of the motor openings 721, 722 and then flow out the other through the motor space 70a. In other words, a path for outside air is more likely to be created inside the motor housing 70.

[0097] The motor holding drive unit 77 is a drive unit for opening and closing the motor cover unit 75. The motor holding drive unit 77 includes an actuator such as an electric motor. The motor holding drive unit 77 is fixed to the motor housing 70. The motor holding drive unit 77 drives the motor cover holder 76 to displace it. The motor holding drive unit 77 displaces the motor cover holder 76 from the holding position to the release position, thereby transitioning the motor cover unit 75 from a closed state to an open state. The motor holding drive unit 77 corresponds to the hold drive unit.

[0098] The motor holding and driving unit 77 is communicatively connected to the flight control device 40. The motor holding and driving unit 77 drives in response to signals from the flight control device 40. The motor holding and driving unit 77 may also be communicatively connected to the inverter control unit 81. In this configuration, signals from the flight control device 40 may be input to the flight control device 40 via the inverter control unit 81.

[0099] The motor lid housing 78 is provided on the outside of the motor outer wall 71. The motor lid housing 78 is capable of housing the motor lid 75 that has been detached from the motor outer wall 71. The motor lid housing 78 has a lid housing opening (not shown). The lid housing opening is an opening that exposes the internal space of the motor lid housing 78. When the motor lid 75 shifts to the open state, it detaches from the motor outer wall 71 and enters the lid housing opening, where it is housed in the motor lid housing 78.

[0100] The motor lid housing 78 is provided on the downwind side of the propeller wind F1 relative to the closed motor lid 75. The motor lid housing 78 is aligned with the motor lid 75 in the axial direction AD. The lid housing opening is open toward the upwind side of the propeller wind F1. In other words, the lid housing opening is open toward the motor lid 75. When the motor lid 75 is opened in a situation where the propeller wind F1 is being generated due to the flight of the eVTOL 10, the motor lid 75 is pushed toward the downwind side by the propeller wind F1 and is housed in the motor lid housing 78 from the lid housing opening.

[0101] When the motor cover 75 is open, outside air tends to flow into the motor space 70a as cooling air from the motor opening 72. In the motor space 70a, heat from the motor 61 tends to be transferred to the cooling air. Then, the cooling air with the heat transferred thereto flows out through the motor opening 72 to the outside, dissipating the heat from the motor 61 to the outside.

[0102] The flight control device 40 performs flight control processing. The flight control processing will be described with reference to the flowchart in Figure 5. The flight control device 40 repeatedly executes the flight control processing at a predetermined control period. The flight control device 40 performs the flight control processing for each of the multiple propulsion devices 100.

[0103] The flight control device 40 acquires eVTOL information in step S101 shown in Figure 5. The eVTOL information is information indicating the status of the eVTOL 10. Examples of eVTOL information include information indicating the flight status of the eVTOL 10 and information indicating the status of the propulsion device 100. Information indicating the status of the propulsion device 100 includes information indicating the drive status of the motor 61 and information indicating the drive status of the holding drive units 77, 97. Examples of eVTOL information include information input to the flight control device 40 from an external device via the communication unit 34.

[0104] In step S102, the flight control device 40 determines whether the EPU temperature Tepu has reached the first temperature threshold T1. The flight control device 40 acquires the EPU temperature Tepu using the detection signal of the temperature sensor 55. The EPU temperature Tepu is the temperature of the driving heat-generating parts, such as the motor 61, the inverter high-voltage section 86, and the inverter low-voltage section 87. The temperature sensor 55 is provided in a position where it can detect the temperatures of the motor 61, the inverter high-voltage section 86, and the inverter low-voltage section 87. For example, a temperature sensor 55 is provided for each of the motor 61, the inverter high-voltage section 86, and the inverter low-voltage section 87. The flight control device 40 then acquires the highest temperature among the temperatures of the motor 61, the inverter high-voltage section 86, and the inverter low-voltage section 87 as the EPU temperature Tepu.

[0105] The flight control device 40 may acquire the EPU temperature Tepu in any manner. For example, the flight control device 40 may calculate the average temperature of the motor 61, the inverter high-voltage section 86, and the inverter low-voltage section 87 as the EPU temperature Tepu. The flight control device 40 may also acquire the temperature of the part of the driving heat-generating part that is most likely to generate heat, the temperature of the part that is most likely to become hot, or the temperature of the part that is most susceptible to heat as the EPU temperature Tepu.

[0106] If the EPU temperature Tepu reaches the first temperature threshold T1, the flight control device 40 determines that a high-temperature abnormality has occurred in a driving heat-generating component, such as the motor 61, the inverter high-voltage unit 86, or the inverter low-voltage unit 87. A high-temperature abnormality is an abnormality in which the temperature of a driving heat-generating component becomes too high. A high-temperature abnormality is also an abnormality indicating that a driving heat-generating component has overheated, and is sometimes referred to as an overheating abnormality. A high-temperature abnormality is an abnormality that occurs when the EPU temperature Tepu reaches the first temperature threshold T1. In other words, a high-temperature abnormality is an abnormality that includes a driving heat-generating component reaching the first temperature threshold T1. Note that a high-temperature abnormality may also include other events or abnormalities that occur when a driving heat-generating component reaches the first temperature threshold T1. Examples of other events or abnormalities include an excessively large motor current, such as reaching a predetermined current, or a driving heat-generating component reaching the second temperature threshold T2, which will be described later.

[0107] The first temperature threshold T1 is a threshold for determining whether the temperature of the driving heat generating portion has become high enough to be considered abnormal. The first temperature threshold T1 is a value determined in advance through testing or the like, and is stored in memory 43 or the like. The first temperature threshold T1 corresponds to a predetermined temperature. The first temperature threshold T1 is also a threshold for determining whether to perform an emergency landing of the eVTOL 10. The first temperature threshold T1 is also a threshold for determining whether to transition the motor cover holding portion 76 and the inverter cover holding portion 96 to a released state. The first temperature threshold T1 corresponds to a release temperature. The function of executing the processing of step S102 in the flight control device 40 corresponds to the high temperature determination portion.

[0108] If the EPU temperature Tepu reaches the first temperature threshold T1, the flight control device 40 proceeds to step S103. In step S103, the flight control device 40 performs high-temperature abnormality processing. The high-temperature abnormality processing includes processing to notify the occurrence of a high-temperature abnormality in the motor 61, the inverter high-voltage section 86, or the inverter low-voltage section 87, and processing to record the occurrence of a high-temperature abnormality in the memory 43, etc.

[0109] The flight control device 40 performs emergency landing processing in step S104. In the emergency landing processing, processing is performed to make an emergency landing of the eVTOL 10. For example, the flight control device 40 performs processing to change the flight route to the destination, or processing to land the eVTOL 10 at an emergency landing point different from the destination. The flight control device 40 also performs processing to continue flying the eVTOL 10 to the destination or emergency landing point. In the emergency landing processing, processing is performed to safely evacuate the eVTOL 10 to the destination or emergency landing point. In other words, in the emergency landing processing, processing is performed to evacuate the eVTOL 10 to a safe state.

[0110] In step S105, the flight control device 40 performs a cover opening process. In the cover opening process, a process is performed to open the motor cover 75 and the inverter cover 95. The flight control device 40 drives the motor holding drive unit 77 so that the motor cover 75 is opened. For example, the flight control device 40 opens the motor cover 75 for both the first motor opening 721 and the second motor opening 722. The flight control device 40 also drives the inverter holding drive unit 97 so that the inverter cover 95 is opened. For example, the flight control device 40 opens the inverter cover 95 for both the first inverter opening 921 and the second inverter opening 922 for each of the first inverter device 801 and the second inverter device 802. In addition, in the cover opening process, an open flag indicating that the motor cover 75 or the inverter cover 95 has been opened is set in the memory 43, etc.

[0111] The flight control device 40 drives the motor holding drive unit 77 so that the motor cover holder 76 transitions to the released state, thereby releasing the fixation of the motor cover unit 75 by the motor cover holder 76. Furthermore, the flight control device 40 drives the inverter holding drive unit 97 so that the inverter cover holder 96 transitions to the released state, thereby releasing the fixation of the inverter cover unit 95 by the inverter cover holder 96. The function of executing the processing of step S105 in the flight control device 40 and the inverter holding drive unit 97 correspond to a cover release unit. Furthermore, the function of executing the processing of step S105 in the flight control device 40 corresponds to a release execution unit.

[0112] When the motor lid 75 is opened by the lid opening process, the motor 61 is directly cooled by the cooling airflow F2 flowing in through the motor opening 72. In this case, the airflow rate in the motor space 70a increases rapidly due to the opening of the motor opening 72, making it easier for the temperature of the motor 61 to decrease. That is, the opening of the motor lid 75 makes it easier for the EPU temperature Tepu to decrease. When the inverter lid 95 is opened by the lid opening process, the inverter high-voltage section 86 and the inverter low-voltage section 87 are directly cooled by the cooling airflow F2 flowing in through the inverter opening 92. In this case, the airflow rate in the inverter space 90a increases rapidly due to the opening of the inverter opening 92, making it easier for the temperatures of the inverter high-voltage section 86 and the inverter low-voltage section 87 to decrease. That is, the opening of the inverter lid 95 makes it easier for the EPU temperature Tepu to decrease.

[0113] In step S106, the flight control device 40 determines whether heat dissipation from the propulsion unit 100 due to the cover opening process has continued. For example, the flight control device 40 measures the time elapsed since performing the high-temperature abnormality process and determines whether the elapsed time has reached a threshold time. The threshold time is a time determined in advance through testing or the like and is stored in the memory 43 or the like. The threshold time is set to the time required for the EPU temperature Tepu to decrease after the motor cover 75 or the inverter cover 95 is opened.

[0114] If heat dissipation from the propulsion unit 100 due to the lid opening process continues, the flight control device 40 proceeds to step S107. In step S107, the flight control device 40 determines whether the EPU temperature Tepu has fallen below the first temperature threshold T1. The EPU temperature Tepu may fall below the first temperature threshold T1 if the motor lid unit 75 or the inverter lid unit 95 is opened normally, or if the heat generated by the drive heat-generating unit is not too great.

[0115] On the other hand, EPU temperature Tepu does not become lower than first temperature threshold T1 when motor lid portion 75 or inverter lid portion 95 is not opened properly, when the heat generated in the drive heat-generating portion is too great, etc. When motor lid portion 75 or inverter lid portion 95 is not opened properly, when motor holding drive portion 77 is not driven properly, when a foreign object is caught on motor lid holding portion 76, etc., and the motor lid holding portion 76 does not move to release position P2.

[0116] If the EPU temperature Tepu becomes lower than the first temperature threshold T1, the flight control device 40 proceeds to step S108. The flight control device 40 performs EPU permission processing in step S108. The EPU permission processing is a process for permitting operation of the EPU 50 until the emergency landing of the eVTOL 10 is completed. The flight control device 40 performs an emergency landing of the eVTOL 10 by driving both the propulsion unit 100 in which a high temperature abnormality has not occurred and the propulsion unit 100 in which a high temperature abnormality has occurred.

[0117] The flight control device 40 performs a re-flight prohibition process in step S109. The re-flight prohibition process is a process for prohibiting the eVTOL 10 from re-flighting. A re-flight occurs when the eVTOL 10 makes an emergency landing and completes its current flight, and then takes off and starts flying again. For example, the flight control device 40 sets a prohibition flag in the memory 43 or the like to prohibit the eVTOL 10 from re-flighting. By setting the prohibition flag, the flight control device 40 restricts the eVTOL 10 from re-flighting. Examples of the re-flight prohibition process include a process for restricting operations to re-fly the eVTOL 10 and a process for restricting the propulsion device 100 from operating after the eVTOL 10 makes an emergency landing. The flight control device 40 restricts the takeoff of the eVTOL 10 by restricting the eVTOL 10 from re-flighting. The function of the flight control device 40 that executes the process of step S109 corresponds to a takeoff restriction unit.

[0118] In step S107, if the EPU temperature Tepu does not fall below the first temperature threshold T1, the flight control device 40 proceeds to step S110. In step S110, the flight control device 40 performs EPU restriction processing. The EPU restriction processing is processing for restricting the operation of the EPU 50. For example, the flight control device 40 prohibits the operation of the EPU 50. The flight control device 40 performs an emergency landing of the eVTOL 10 by stopping the operation of the propulsion device 100 in which a high temperature abnormality has occurred and operating the propulsion device 100 in which a high temperature abnormality has not occurred. The flight control device 40 performs processing such as adjusting the output of the propulsion device 100 in which a high temperature abnormality has not occurred to compensate for the output of the propulsion device 100 in which a high temperature abnormality has occurred. The function of the flight control device 40 that executes the processing of step S110 corresponds to a drive stopping unit.

[0119] In step S102, if the EPU temperature Tepu has not reached the first temperature threshold T1, the flight control device 40 proceeds to step S111. In step S111, the flight control device 40 determines whether the motor cover unit 75 or the inverter cover unit 95 is open. For example, the flight control device 40 determines whether an open flag is set. If the open flag is set, the flight control device 40 determines that the motor cover unit 75 or the inverter cover unit 95 is open. Note that the flight control device 40 may also determine the open state of the motor cover unit 75 or the inverter cover unit 95 by obtaining the operation history of the motor holding / driving unit 77 or the inverter holding / driving unit 97, detecting the position of the motor cover holding unit 76 or the inverter cover holding unit 96, or the like.

[0120] An example of a case in which the motor lid 75 or the inverter lid 95 is open is when, after a high temperature abnormality occurs in a drive heat generating part, the EPU temperature Tepu falls below the first temperature threshold T1 due to the opening of the motor lid 75 or the inverter lid 95. If the motor lid 75 or the inverter lid 95 is open, the flight control device 40 proceeds to steps S106 to S108, and performs EPU permission processing in step S108.

[0121] According to the present embodiment described so far, when a drive-heat-generating component, such as the motor 61, inverter high-voltage component 86, or inverter low-voltage component 87, experiences an abnormally high temperature, the lids 75, 95 are released from the lid holders 76, 96, thereby opening the lids 75, 95. With this configuration, if the drive-heat-generating component becomes so hot that it interferes with the operation of the motor 61, the lids 75, 95 are opened, allowing outside air, such as cooling air F2, to flow in through the openings 72, 92. This allows the outside air flowing in through the openings 72, 92 to directly cool the drive-heat-generating component. This prevents the drive-heat-generating component from becoming too hot, causing the motor 61 to immediately stop operating, or prevents the drive-heat-generating component from becoming too hot, reducing the degree of freedom of the motor 61 as the temperature of the drive-heat-generating component rises. Therefore, even if a drive-heat-generating component experiences an abnormally high temperature, the motor 61 can continue to operate until the eVTOL 10 is evacuated to a safe state. As described above, the safety of the eVTOL 10 can be ensured even if an abnormality occurs in the propulsion system 30.

[0122] Note that an increase in the temperature of the driving heat-generating portion can reduce the degree of freedom of the motor 61, such as when the motor output is limited. It is conceivable that the higher the temperature of the driving heat-generating portion of the motor 61, the more difficult it becomes for the motor current to flow, resulting in a decrease in motor output. Such a decrease in motor output raises concerns that the motor output may be insufficient for the flight of the eVTOL 10. In contrast, in this embodiment, the improved cooling effect associated with opening the lids 75 and 95 reduces the temperature of the driving heat-generating portion, making it easier for the motor current to flow, and thus reducing the likelihood of a decrease in motor output. In this way, the degree of freedom of the motor 61 can be prevented from decreasing, thereby preventing the motor output from becoming insufficient for the flight of the eVTOL 10.

[0123] According to this embodiment, when an abnormally high temperature occurs in the drive heat generating portion, the flight control device 40 drives the holding drive unit 77, 97 so that the cover holding unit 76, 96 transitions to the released state. This configuration allows the flight control device 40 to accurately manage the timing of opening the cover units 75, 95. Therefore, the cooling effect of opening the cover units 75, 95 can be effectively improved in response to an abnormally high temperature in the drive heat generating portion.

[0124] According to this embodiment, when the EPU temperature Tepu reaches the first temperature threshold T1, the flight control device 40 determines that a high temperature abnormality has occurred in the drive heat-generating portion, and drives the holding drive unit 77, 97 to transition the lid holding unit 76, 96 to the released state. This configuration prevents the lid unit 75, 95 from being opened even when the EPU temperature Tepu has not reached the first temperature threshold T1. In other words, it prevents the lid unit 75, 95 from being opened even when a high temperature abnormality has not occurred in the drive heat-generating portion. This prevents the lid unit 75, 95 from being opened and foreign matter from entering the housing 70, 90 through the opening 72, 92 when a high temperature abnormality has not occurred in the drive heat-generating portion.

[0125] Furthermore, with this configuration, the lids 75, 95 can be opened only when a predetermined condition is met, that is, when the EPU temperature Tepu reaches the first temperature threshold T1. Therefore, the drive heat generating components can be cooled by outside air as intended by the designer or pilot.

[0126] According to this embodiment, the second motor opening 722 is located at a position that allows the motor 61 and other driving heat-generating components to be exposed to the outside of the motor housing 70 and is aligned with the first motor opening 721 in the radial direction RD. With this configuration, opening both the first motor opening 721 and the second motor opening 722 makes it easier for outside air, such as cooling air, to reach the driving heat-generating components, thereby improving the cooling effect of the driving heat-generating components by the outside air. Furthermore, the second inverter opening 922 is located at a position that allows the inverter high-voltage section 86 and the inverter low-voltage section 87 and other driving heat-generating components to be exposed to the outside of the inverter housing 90 and is aligned with the first inverter opening 921 in the radial direction RD. With this configuration, opening both the first inverter opening 921 and the second inverter opening 922 makes it easier for outside air, such as cooling air, to reach the driving heat-generating components, thereby improving the cooling effect of the driving heat-generating components by the outside air.

[0127] According to this embodiment, the motor 61 is exposed to the outside through the motor opening 72 when the motor cover 75 is released. In this configuration, the outside air flowing in through the motor opening 72 is likely to hit the motor 61. This makes it possible to realize a configuration that is likely to improve the cooling effect of the outside air on the motor 61.

[0128] According to this embodiment, the inverter low-voltage section 87 is exposed to the outside through the inverter opening 92 when the inverter lid 95 is released. In this configuration, the outside air flowing in through the inverter opening 92 is likely to hit the inverter low-voltage section 87. This makes it possible to realize a configuration that is likely to improve the cooling effect of the outside air on the inverter low-voltage section 87. Similarly, the inverter high-voltage section 86 is exposed to the outside through the inverter opening 92 when the inverter lid 95 is released. In this configuration, the outside air flowing in through the inverter opening 92 is likely to hit the inverter high-voltage section 86. This makes it possible to realize a configuration that is likely to improve the cooling effect of the outside air on the inverter high-voltage section 86.

[0129] When a high temperature abnormality occurs in the drive heat generating portion, if the high temperature abnormality in the drive heat generating portion is not resolved even though the cooling effect of the drive heat generating portion by outside air is improved by opening the lid portions 75, 95, there is a concern that a secondary abnormality due to the high temperature abnormality may occur in the propulsion device 100. Possible reasons why the high temperature abnormality in the drive heat generating portion is not resolved even when the lid portions 75, 95 are opened include insufficient cooling of the drive heat generating portion by outside air even when the lid portions 75, 95 are opened, or the heat generated in the drive heat generating portion is too great.

[0130] In contrast, according to this embodiment, the flight control device 40 stops driving the motor 61 if the high temperature abnormality in the drive heat-generating portion continues even when the cover portions 75, 95 are open. This prevents a secondary abnormality from occurring due to the continued high temperature abnormality in the propulsion device 100. This prevents a reduction in the safety of the eVTOL 10 due to the occurrence of a secondary abnormality caused by the high temperature abnormality.

[0131] If a high temperature abnormality occurs in the drive heat generating portion, maintenance of the propulsion device 100 must be performed to prevent the high temperature abnormality from recurring. In contrast, according to this embodiment, the flight control device 40 restricts the takeoff of the eVTOL 10 when the lids 75, 95 are opened. This prevents the eVTOL 10 from taking off again without performing maintenance on the propulsion device 100, despite the possibility that a high temperature abnormality in the drive heat generating portion will recur. This prevents the safety of the eVTOL 10 from being reduced during the next flight due to the occurrence of a high temperature abnormality in the drive heat generating portion.

[0132] In propulsion device 100, high temperature abnormalities that require opening lids 75, 95 for the drive heat-generating components should not occur if EPU 50 is normal. Furthermore, even if the temperature of the drive heat-generating components drops quickly by opening lids 75, 95, continued use of EPU 50 as is carries risks because parts of EPU 50 that should be sealed, such as the drive heat-generating components, are exposed to the atmosphere. For this reason, EPU 50 continues to operate until the eVTOL 10 completes its emergency landing, but it is preferable to prohibit eVTOL 10 from flying again so that the EPU 50 can be inspected or replaced before the next flight.

[0133] For example, in a vehicle such as an electric automobile that moves on the ground as a moving body, if an abnormally high temperature occurs in a heat-generating part that drives the motor, the vehicle can be stopped, even if the vehicle's propulsive force becomes insufficient, thereby ensuring the safety of the vehicle and its occupants. In contrast, in a manned aircraft such as the eVTOL 10 that flies away from the ground, if an abnormally high temperature occurs in a heat-generating part that drives the motor, it is necessary to avoid a situation in which the manned aircraft's propulsive force becomes insufficient until landing is completed, in order to protect the safety of the occupants.

[0134] For this reason, as in the present embodiment, in the case of eVTOL 10, when an abnormally high temperature occurs in the driving heat-generating portion, it is preferable to continue driving motor 61 to prioritize ensuring the safety of the occupants, rather than stopping the driving of motor 61 to minimize the abnormality in motor 61. Continuing to drive motor 61 despite the occurrence of an abnormally high temperature in the driving heat-generating portion is a last resort for motor 61. In eVTOL 10, opening lids 75, 95 allows the motor 61 to effectively utilize this last resort.

[0135] The propulsion device 100 mounted on the eVTOL 10 is required to have high output and be lightweight in order to extend the cruising range of the eVTOL 10. For example, high output requires an output of several tens to several hundred kW for each propulsion device 100. The propulsion device 100 of the eVTOL 10 is likely to have strict thermal design due to factors such as increased heat generation from the drive heat-generating components due to higher output and reduced heat dissipation effectiveness due to reduced weight. Furthermore, there is concern that a propulsion device 100 with strict thermal design is more likely to experience abnormally high temperatures in the drive heat-generating components. Therefore, as in the present embodiment, the lids 75, 95 are openable as a countermeasure against abnormally high temperatures in the drive heat-generating components, thereby improving the safety of the eVTOL 10 even when the thermal design of the propulsion device 100 mounted on the eVTOL 10 is strict.

[0136] According to this embodiment, the housings 70, 90 are provided with vents 73, 93 and ventilation filters 73a, 93a in addition to the openings 72, 92. With this configuration, even if the temperature of the drive heat-generating portion rises, as long as the temperature does not reach an abnormally high temperature, the drive heat-generating portion can be cooled by ventilation through the vents 73, 93. Therefore, when the drive heat-generating portion is not abnormally high in temperature, there is no need to open the openings 72, 92. Furthermore, the ventilation filters 73a, 93a prevent foreign matter from entering the housings 70, 90 and causing an abnormality in the propulsion device 100.

[0137] On the other hand, if an abnormally high temperature occurs in the drive heat generating portion, it is possible to release a large amount of heat from the drive heat generating portion to the outside through the openings 72, 92 in addition to the ventilation holes 73, 93. In this case, by prioritizing a rapid increase in the cooling effect of the drive heat generating portion by the outside air over preventing foreign matter from entering through the openings 72, 92, it is possible to avoid a situation in which the drive of the motor 61 or the drive heat generating portion immediately stops due to an abnormally high temperature in the drive heat generating portion.

[0138] Second Embodiment In a second embodiment, the motor current can be limited when no abnormally high temperature occurs in the driving heat generating portion. The configuration, operation, and effects not specifically described in the second embodiment are the same as those in the first embodiment. The second embodiment will be described focusing on the differences from the first embodiment.

[0139] The flight control device 40 performs flight control processing in the same manner as in the first embodiment. In this embodiment, the flight control processing will be described with reference to the flowchart in Figure 6. The flight control device 40 performs the processing of steps S101 to S111 in the same manner as in the first embodiment.

[0140] If the motor cover 75 or the inverter cover 95 is open in step S111, the flight control device 40 proceeds to step S201. In step S201, the flight control device 40 determines whether the EPU temperature Tepu has reached the second temperature threshold T2. The second temperature threshold T2 is a value determined in advance through testing or the like and stored in the memory 43 or the like. The second temperature threshold T2 is set to a value indicating a temperature lower than the first temperature threshold T1. In other words, the first temperature threshold T1 is a value indicating a temperature higher than the second temperature threshold T2. The second temperature threshold T2 is a threshold used to determine whether to limit the motor current to reduce the rate of increase in the EPU temperature Tepu when the EPU temperature Tepu becomes higher than normal. The second temperature threshold T2 corresponds to the limit temperature.

[0141] If the EPU temperature Tepu reaches the second temperature threshold T2, the flight control device 40 proceeds to step S202. In step S202, the flight control device 40 performs current limiting processing. In current limiting processing, processing is performed to limit the motor current. For example, the flight control device 40 sets the required output for the motor 61 to a value that reduces the motor current. However, the flight control device 40 performs current limiting processing so that the motor current does not become zero. When current limiting processing is performed, the rate of increase in the EPU temperature Tepu is more likely to be reduced. This makes it less likely that high temperatures will occur in the driving heat-generating parts. The processing of step S202 in the flight control device 40 corresponds to the current limiting section.

[0142] In this embodiment, a normal region, a current limit region, and a high temperature abnormal region are set for the EPU temperature Tepu. When the EPU temperature Tepu is in the normal region, the flight control device 40 does not execute either the EPU limit process or the current limit process. When the EPU temperature Tepu is in the current limit region, the flight control device 40 executes the current limit process. When the EPU temperature Tepu is in the high temperature abnormal region, the flight control device 40 executes the EPU limit process. The normal region is a region where the EPU temperature Tepu is lower than the second temperature threshold T2. The current limit region is a region where the EPU temperature Tepu is equal to or higher than the second temperature threshold T2 and lower than the first temperature threshold T1. The high temperature abnormal region is a region where the EPU temperature Tepu is equal to or higher than the first temperature threshold T1.

[0143] According to this embodiment, the flight control device 40 limits the motor current when the EPU temperature Tepu reaches the second temperature threshold T2. In this configuration, limiting the motor current reduces the rate of increase in the EPU temperature Tepu, making it less likely that the EPU temperature Tepu will reach the first temperature threshold T1 after exceeding the second temperature threshold T2. This makes it possible to prevent the drive heat-generating portion from becoming abnormally high in temperature.

[0144] <Third Embodiment> In the first embodiment described above, the flight control device 40 needs to drive the holding drive units 77, 97 to open the lid units 75, 95. In contrast, in the third embodiment, the flight control device 40 does not need to drive the holding drive units 77, 97 to open the lid units 75, 95. Configurations, actions, and effects not specifically described in the third embodiment are the same as those in the first embodiment described above. The third embodiment will be described mainly focusing on differences from the first embodiment described above.

[0145] As shown in Figure 7, the motor device 60 has a motor lid holding portion 176 and a motor lid housing portion 178 instead of the motor lid holding portion 76 and the motor lid housing portion 78 of the first embodiment. Unlike the first embodiment, the motor device 60 does not have the motor holding / driving portion 77. The motor lid holding portion 176 and the motor lid housing portion 178 are provided in the first motor opening 721 and the second motor opening 722, respectively. The motor lid holding portion 176 corresponds to the lid holding portion.

[0146] The inverter device 80 has an inverter lid holding portion 196 and an inverter lid accommodating portion 198 instead of the inverter lid holding portion 96 and the inverter lid accommodating portion 98 of the first embodiment. Unlike the first embodiment, the inverter device 80 does not have the inverter holding and driving portion 97. The inverter lid holding portion 196 and the inverter lid accommodating portion 198 are provided in the first inverter opening 921 and the second inverter opening 922, respectively. The inverter lid holding portion 196 corresponds to the lid holding portion.

[0147] As shown in Figures 7 and 8, the inverter lid holding portion 196 holds the inverter lid portion 95 in a closed state. Like the inverter lid holding portion 96 of the first embodiment, the inverter lid holding portion 196 is capable of transitioning between a held state and a released state. When in the held state, the inverter lid holding portion 196 holds the inverter lid portion 95 in a closed state. When the inverter lid holding portion 196 transitions to the released state, it transitions the inverter lid portion 95 to an open state. The inverter lid holding portion 196 corresponds to a lid holding portion.

[0148] As shown in FIGS. 8 and 9 , the inverter lid holding portion 196 transitions from the holding state to the release state when at least a portion of the inverter lid holding portion 196 is deformed. The inverter lid holding portion 196 is in the holding state by assuming a holding shape. The holding shape is a shape that allows the inverter lid holding portion 196 to hold the inverter lid portion 95 in the closed state. When in the holding shape, the inverter lid holding portion 196 holds the inverter lid portion 95 in the closed state (see FIG. 8 ). The inverter lid holding portion 196 transitions from the holding state to the release state by transforming from the holding shape to the release shape. The release shape is a shape that allows the inverter lid holding portion 196 to transition the inverter lid portion 95 from the closed state to the open state. In other words, the release shape is a shape that releases the inverter lid holding portion 196 from its hold on the inverter lid 95. When the inverter lid holding portion 196 is transformed into the release shape, the inverter lid holding portion 196 transitions the inverter lid 95 to the open state (see FIG. 9 ). The inverter lid holding portion 196 corresponds to a lid release portion.

[0149] The inverter lid holding portion 196 has an inverter deformation portion 196a. The inverter deformation portion 196a forms at least a part of the inverter lid holding portion 196. For example, the inverter deformation portion 196a forms the entire inverter lid holding portion 196. The inverter lid holding portion 196 is deformed from the holding shape to the release shape by deformation of at least a part of the inverter deformation portion 196a. The inverter deformation portion 196a corresponds to the release deformation portion. The inverter lid holding portion 196 is sometimes referred to as a fusible plug.

[0150] The inverter deformable portion 196a is made of a metal material or the like. The thermal deformation temperature of the inverter deformable portion 196a is lower than the thermal deformation temperatures of the inverter outer wall 91, the inverter lid portion 95, and the inverter lid accommodating portion 198. The inverter deformable portion 196a is deformed by melting or the like when exposed to heat. Note that in a configuration in which the inverter deformable portion 196a forms part of the inverter lid holding portion 196, the thermal deformation temperature of the inverter deformable portion 196a is lower than the thermal deformation temperatures of other portions of the inverter lid holding portion 196.

[0151] In the inverter device 80, heat from the driving heat generating portion is applied to the inverter lid holding portion 196. In the inverter device 80, when the temperature of the driving heat generating portion becomes high enough to be considered abnormally high, the heat applied from the driving heat generating portion to the inverter lid holding portion 196 causes the inverter lid holding portion 196 to deform from the holding shape to the release shape. In this case, the heat from the driving heat generating portion is applied to the inverter deforming portion 196a, deforming at least a portion of the inverter deforming portion 196a and causing the inverter lid holding portion 196 to deform from the holding shape to the release shape. For example, when the EPU temperature Tepu reaches a first temperature threshold T1, the heat from the driving heat generating portion deforms the inverter deforming portion 196a, causing the inverter lid holding portion 196 to deform from the holding shape to the release shape. The first temperature threshold T1 corresponds to the release shape temperature.

[0152] Similar to the inverter lid holding portion 96 of the first embodiment, the inverter lid holding portion 196 detachably fixes the inverter lid portion 95 to the inverter outer wall 91. When the inverter lid holding portion 196 is in the holding shape, the inverter lid portion 95 is in a closed state by being fixed to the inverter outer wall 91 by the inverter lid holding portion 196. When the inverter lid holding portion 196 is in the released shape, the inverter lid portion 95 is released from the inverter outer wall 91 and is in an open state.

[0153] The inverter lid accommodating portion 198 is provided on the outside of the inverter outer wall 91, similar to the inverter lid accommodating portion 98 in the first embodiment. The inverter lid accommodating portion 198 is capable of accommodating the inverter lid portion 95 that has come off the inverter outer wall 91. The inverter lid accommodating portions 198 are arranged in pairs in the axial direction AD with the inverter opening portion 92 interposed therebetween. The inverter lid accommodating portion 198 is provided so that the end of the inverter lid portion 95 that has come off the inverter outer wall 91 can be caught thereon.

[0154] The inverter lid housing 198 has a housing vent 198a. The housing vent 198a penetrates the inverter lid housing 198 in the axial direction AD. The housing vent 198a is provided to facilitate the passage of the propeller airflow F1 and the cooling airflow F2 in the axial direction AD. When the inverter lid 95 is opened, the cooling airflow F2 is likely to pass through the housing vent 198a and flow into the inverter opening 92 in the inverter lid housing 198 that is provided on the upwind side of the propeller airflow F1 out of the pair of inverter lid housings 198.

[0155] As shown in FIG. 7 , the motor cover holder 176 holds the motor cover 75 in a closed state. Like the motor cover holder 76 of the first embodiment, the motor cover holder 176 is capable of transitioning between a held state and a released state. When in the held state, the motor cover holder 176 holds the motor cover 75 in a closed state. When the motor cover holder 176 transitions to the released state, it transitions the motor cover 75 to an open state. A motor cover holder 176 is provided for each of the first motor opening 721 and the second motor opening 722. The motor cover holder 176 corresponds to a cover holder.

[0156] The motor cover holding portion 176 transitions from the holding state to the release state when at least a portion of the motor cover holding portion 176 is deformed. The motor cover holding portion 176 is in the holding state when it is in a holding shape. The holding shape is a shape that allows the motor cover holding portion 176 to hold the motor cover 75 in the closed state. When the motor cover holding portion 176 is in the holding shape, it holds the motor cover 75 in the closed state. The motor cover holding portion 176 transitions from the holding state to the release state by transforming from the holding shape to the release shape. The release shape is a shape that allows the motor cover holding portion 176 to transition the motor cover 75 from the closed state to the open state. In other words, the release shape is a shape that releases the motor cover holding portion 176 from its hold on the motor cover 75. When the motor cover holding portion 176 is transformed into the release shape, it transitions the motor cover 75 to the open state. The motor cover holding portion 176 corresponds to a lid release portion.

[0157] The configuration of the motor lid holder 176 is similar to the configuration of the inverter lid holder 196 shown in Figures 8 and 9. The configuration of the motor lid holder 176 is not shown in the figures.

[0158] The motor cover holder 176 has a motor deformation portion 176a. The motor deformation portion 176a forms at least a portion of the motor cover holder 176. For example, the motor deformation portion 176a forms the entire motor cover holder 176. The motor cover holder 176 is transformed from a holding shape to a release shape by deformation of at least a portion of the motor deformation portion 176a. The motor deformation portion 176a corresponds to a release deformation portion. The motor cover holder 176 is sometimes referred to as a fusible plug.

[0159] The motor deformation portion 176a is made of a metal material or the like. The thermal deformation temperature of the motor deformation portion 176a is lower than the thermal deformation temperatures of the motor outer wall 71, the motor lid portion 75, and the motor lid housing portion 178. The motor deformation portion 176a is deformed by melting or the like when exposed to heat. Note that in a configuration in which the motor deformation portion 176a forms part of the motor lid holding portion 176, the thermal deformation temperature of the motor deformation portion 176a is lower than the thermal deformation temperatures of other portions of the motor lid holding portion 176.

[0160] In the motor device 60, heat from the drive heat generating portion is applied to the motor lid holding portion 176. In the motor device 60, if the temperature of the drive heat generating portion becomes high enough to constitute an abnormally high temperature, the heat applied from the drive heat generating portion to the motor lid holding portion 176 causes the motor lid holding portion 176 to deform from the holding shape to the released shape. In this case, the heat from the drive heat generating portion is applied to the motor deformation portion 176a, causing at least a portion of the motor deformation portion 176a to deform, thereby causing the motor lid holding portion 176 to deform from the holding shape to the released shape. For example, if the EPU temperature Tepu reaches the first temperature threshold T1, the heat from the drive heat generating portion deforms the motor deformation portion 176a, causing the motor lid holding portion 176 to deform from the holding shape to the released shape.

[0161] Similar to the motor cover holder 76 of the first embodiment, the motor cover holder 176 removably secures the motor cover 75 to the motor outer wall 71. When the motor cover holder 176 is in the retaining shape, the motor cover 75 is in a closed state by being secured to the motor outer wall 71 by the motor cover holder 176. When the motor cover holder 176 is in the released shape, the motor cover 75 is released from the motor outer wall 71 and is in an open state.

[0162] The motor lid housing 178 is provided on the outside of the motor outer wall 71, similar to the motor lid housing 78 of the first embodiment. The motor lid housing 178 is capable of housing the motor lid 75 that has come off the motor outer wall 71. The motor lid housings 178 are arranged in pairs, with the motor opening 72 sandwiched between them. The motor lid housing 178 is provided so that the end of the motor lid 75 that has come off the motor outer wall 71 can be caught thereon.

[0163] The motor lid housing 178 has a housing vent (not shown). The housing vent penetrates the motor lid housing 178 in the axial direction AD. The housing vent is provided to facilitate the passage of the propeller air F1 and the cooling air F2 in the axial direction AD. When the motor lid 75 is opened, the cooling air F2 is likely to pass through the housing vent and flow into the motor opening 72 in the motor lid housing 178 that is provided on the upwind side of the propeller air F1 out of the pair of motor lid housings 178.

[0164] In this embodiment, the flight control process will be described with reference to the flowchart in Figure 10. The flight control device 40 performs the processes of steps S101 to S104 and S106 to S110, similar to the first embodiment. In addition, the flight control device 40 performs the processes of steps S201 and S202, similar to the second embodiment.

[0165] After step S101, the flight control device 40 proceeds to step S301. In step S301, the flight control device 40 determines whether the motor cover 75 or the inverter cover 95 is in the open state. For example, the flight control device 40 determines whether the motor cover 75 or the inverter cover 95 is in the open state using a detection signal from a cover sensor. The cover sensor is a sensor that detects the state of the motor cover 75, the inverter cover 95, the motor cover holder 176, and the inverter cover holder 196. For example, the cover sensor detects that the motor cover holder 176 or the inverter cover holder 196 has been deformed into the released shape.

[0166] The motor lid 75 or the inverter lid 95 may be in the open state if an abnormally high temperature occurs in the drive heat-generating portion. For example, if an abnormally high temperature occurs in the motor 61, the heat from the motor 61 causes the motor deformation portion 176a to melt or deform, and the motor lid holder 176 deforms into the released shape. In this case, the fixation of the motor lid 75 by the motor lid holder 176 is released, and the motor lid 75 is opened. Furthermore, if an abnormally high temperature occurs in the inverter high-voltage portion 86 or the inverter low-voltage portion 87, the heat from the inverter high-voltage portion 86 or the inverter low-voltage portion 87 causes the inverter deformation portion 196a to melt or deform, and the inverter lid holder 196 deforms into the released shape. In this case, the fixation of the inverter lid 95 by the inverter lid holder 196 is released, and the inverter lid 95 is opened.

[0167] When the motor cover 75 or the inverter cover 95 is in the open state, the flight control device 40 performs a notification process. This notification process includes a process for notifying the user that the motor cover 75 or the inverter cover 95 is in the open state, and a process for recording in the memory 43 or the like that the motor cover 75 or the inverter cover 95 has entered the open state.

[0168] If the motor cover 75 or the inverter cover 95 is open, the flight control device 40 proceeds to step S102 and determines whether the EPU temperature Tepu has reached the first temperature threshold T1. When the cover 75, 95 is open, the EPU temperature Tepu may not have reached the first temperature threshold T1 if the cover holder 176, 196 is unintentionally deformed into the released shape or if the EPU temperature Tepu has dropped due to cooling caused by opening the cover 75, 95.

[0169] If the EPU temperature Tepu is equal to or greater than the first temperature threshold T1 in step S102, the flight control device 40 proceeds to step S302 after steps S103 and S104. In step S302, the flight control device 40 performs current limiting processing, similar to step S202 in the second embodiment. In addition to cooling the drive heat-generating components by opening the lids 75, 95, the flight control device 40 reduces the heat generated by the drive heat-generating components by current limiting processing, thereby creating an environment in which the temperature of the drive heat-generating components can easily decrease.

[0170] In the current limiting process of step S302, the motor current is limited more strictly than in the current limiting process of step S202. For example, in step S302, the current limiting process is performed so that the amount of reduction in the motor current is greater than the amount of reduction in step S202. In this way, when EPU temperature Tepu is equal to or greater than first temperature threshold T1, EPU temperature Tepu is more likely to decrease due to the limit on the motor current than when EPU temperature Tepu is lower than first temperature threshold T1.

[0171] After step S302, if EPU temperature Tepu becomes lower than first temperature threshold T1 in step S107, the flight control device 40 proceeds to step S303. In step S303, the flight control device 40 performs current limit relaxation processing. This current limit relaxation processing is performed to relax the motor current restriction imposed by the current limit processing. The flight control device 40 performs processing such as increasing the required output set in the current limit processing to increase the motor current compared to the current limit processing. For example, the flight control device 40 performs current limit relaxation processing such that the motor current increases as the difference between EPU temperature Tepu and first temperature threshold T1 increases.

[0172] If the situation in which the EPU temperature Tepu is lower than the first temperature threshold T1 is maintained, the flight control device 40 may set the required output to a value greater than when no high-temperature abnormality is occurring. Furthermore, if the above situation is maintained, the flight control device 40 may set the required output to a value greater than that for the propulsion device 100 in which no high-temperature abnormality is occurring. This facilitates reducing the load on the propulsion device 100 in which no high-temperature abnormality is occurring. The propulsion device 100 in which a high-temperature abnormality is occurring is likely to be repaired or replaced after the eVTOL 10 completes its emergency landing. Therefore, from the perspective of preventing abnormalities in the propulsion device 100 in which no high-temperature abnormality is occurring, it is preferable to prioritize reducing the load on the propulsion device 100 in which no high-temperature abnormality is occurring over reducing the load on the propulsion device 100 in which a high-temperature abnormality is occurring.

[0173] If EPU temperature Tepu has not reached first temperature threshold T1 in step S102, the flight control device 40 performs steps S106 to S110 and S303. In this way, even if EPU temperature Tepu has not reached first temperature threshold T1, the flight control device 40 can perform EPU permission processing or EPU restriction processing as long as the motor cover 75 or inverter cover 95 is open.

[0174] If the motor cover 75 or the inverter cover 95 is not in the open state in step S301, the flight control device 40 proceeds to step S201 and determines whether the EPU temperature Tepu has reached the second temperature threshold T2. The motor cover holder 176 or the inverter cover holder 196 is designed not to deform to the released shape when the EPU temperature Tepu reaches the second temperature threshold T2. When the EPU temperature Tepu reaches the second temperature threshold T2, the flight control device 40 performs the current limiting process in step S202, thereby creating an environment in which the motor cover holder 176 or the inverter cover holder 196 is less likely to deform to the released shape.

[0175] According to this embodiment, the deformation portions 176a, 196a are deformed by heat generated by the drive heat-generating portion due to an abnormally high temperature in the drive heat-generating portion, thereby deforming the lid holders 176, 196 into the released shape. With this configuration, the lid portions 75, 95 are opened using the heat generated in the drive heat-generating portion, eliminating the need for the flight control device 40 to manage the opening of the lid portions 75, 95. Therefore, even if an abnormality in the flight control device 40 occurs in addition to an abnormally high temperature in the drive heat-generating portion, the lid portions 75, 95 can be opened without relying on the control of the flight control device 40, thereby improving the cooling effect of the drive heat-generating portion by the outside air.

[0176] According to this embodiment, the deformable portions 176a, 196a are formed to deform the lid holders 176, 196 into the release shape when the EPU temperature Tepu reaches the first temperature threshold T1. This configuration makes it less likely that the lids 75, 95 will be opened due to deformation of the deformable portions 176a, 196a even when the EPU temperature Tepu has not yet reached the first temperature threshold T1. In other words, it is less likely that the lids 75, 95 will be opened due to deformation of the deformable portions 176a, 196a even when there is no abnormally high temperature in the driving heat-generating portion. Therefore, the deformable portions 176a, 196a can prevent foreign matter from entering the housings 70, 90 through the openings 72, 92 when there is no abnormally high temperature in the driving heat-generating portion.

[0177] According to this embodiment, the flight control device 40 limits the motor current when the EPU temperature Tepu reaches the second temperature threshold T2 while the cover holders 176, 196 have not yet deformed to the released shape. With this configuration, limiting the motor current reduces the rate of increase in the EPU temperature Tepu, making it less likely that the EPU temperature Tepu will rise to the point where the cover holders 176, 196 deform to the released shape after the EPU temperature Tepu exceeds the second temperature threshold T2. This prevents the cover holders 176, 196 from deforming to the released shape, thereby preventing the cover 75, 95 from being opened.

[0178] <Fourth embodiment> In a fourth embodiment, the first opening and the second opening are provided at positions offset in the axial direction AD. The configuration, operation, and effects of the fourth embodiment that are not specifically described are the same as those of the third embodiment. The fourth embodiment will be described mainly focusing on the differences from the third embodiment.

[0179] 11 , in the motor device 60, the first motor opening 721 and the second motor opening 722 are positioned offset in the axial direction AD. For example, the first motor opening 721 and the second motor opening 722 are aligned in the radial direction RD or the circumferential direction CD. That is, at least a portion of the first motor opening 721 and at least a portion of the second motor opening 722 are aligned in the radial direction RD across the motor 61.

[0180] The first motor opening 721 is positioned offset toward the propeller 20 from the second motor opening 722. The first motor opening 721 extends further toward the propeller 20 than the second motor opening 722. The second motor opening 722 extends further toward the opposite side from the propeller 20 than the first motor opening 721.

[0181] The first motor opening 721 is positioned upwind of the propeller wind F1 from the second motor opening 722. When both the first motor opening 721 and the second motor opening 722 are open, the propeller wind F1 is more likely to flow into the first motor opening 721 than into the second motor opening 722. The propeller wind F1 that flows into the motor space 70a from the first motor opening 721 is more likely to flow out of the motor housing 70 from the second motor opening 722.

[0182] The motor device 60 has two motor rotors 63, a first rotor and a second rotor. The first rotor and the second rotor are aligned in the axial direction AD via the motor stator 62. A first motor opening 721 is provided near the first rotor, and a second motor opening 722 is provided near the second rotor. The first motor opening 721 is provided in a position that allows at least a portion of the first rotor to be exposed to the outside of the motor housing 70. The first motor opening 721 is provided in a position that is aligned with the first rotor in the radial direction RD. The second motor opening 722 is provided in a position that allows at least a portion of the second rotor to be exposed to the outside of the motor housing 70. The second motor opening 722 is provided in a position that is aligned with the second rotor in the radial direction RD.

[0183] Note that the first motor opening 721 and the second motor opening 722 do not have to be aligned in the radial direction RD as long as they are offset in the axial direction AD. For example, the first motor opening 721 and the second motor opening 722 may be located adjacent to each other in the circumferential direction CD. In this configuration, the motor 61 does not become trapped between the first motor opening 721 and the second motor opening 722. Furthermore, the offset in the axial direction AD between the first motor opening 721 and the second motor opening 722 includes an offset in the axial direction AD between the first motor opening 721 and the second motor opening 722. In this configuration, the first motor opening 721 and the second motor opening 722 may be offset in the circumferential direction CD.

[0184] In this embodiment, the first motor opening 721 and the second motor opening 722 are offset in the axial direction AD, so that the motor lid portion 75 covering the first motor opening 721 and the motor lid portion 75 covering the second motor opening 722 are offset in the axial direction AD. The configuration in which the first motor opening 721 and the second motor opening 722 are offset in the axial direction AD may be applied to the first embodiment. Also, the motor housing 70 does not need to be provided with the motor lid receiving portion 78, 178.

[0185] In the inverter device 80, the first inverter opening 921 and the second inverter opening 922 are positioned offset in the axial direction AD. For example, at least a portion of the first inverter opening 921 and at least a portion of the second inverter opening 922 are aligned in the radial direction RD or the circumferential direction CD. For example, at least a portion of the first inverter opening 921 and at least a portion of the second inverter opening 922 are aligned in the radial direction RD across the motor 61.

[0186] The first inverter opening 921 is positioned offset toward the propeller 20 from the second inverter opening 922. The first inverter opening 921 extends toward the propeller 20 further than the second inverter opening 922. The second inverter opening 922 extends toward the opposite side from the propeller 20 further than the first inverter opening 921.

[0187] The first inverter opening 921 is located at a position shifted toward the upwind side of the propeller wind F1 from the second inverter opening 922. When both the first inverter opening 921 and the second inverter opening 922 are open, the propeller wind F1 is more likely to flow into the first inverter opening 921 than into the second inverter opening 922. The propeller wind F1 that flows into the inverter space 90a from the first inverter opening 921 is more likely to flow out of the inverter housing 90 from the second inverter opening 922.

[0188] Note that the first inverter opening 921 and the second inverter opening 922 do not have to be aligned in the radial direction RD as long as they are offset in the axial direction AD. For example, the first inverter opening 921 and the second inverter opening 922 may be positioned adjacent to each other in the circumferential direction CD. In this configuration, the motor 61 does not get caught between the first inverter opening 921 and the second inverter opening 922. Furthermore, the configuration in which the first inverter opening 921 and the second inverter opening 922 are offset in the axial direction AD includes a configuration in which the first inverter opening 921 and the second inverter opening 922 are aligned in the axial direction AD. In this configuration, the first inverter opening 921 and the second inverter opening 922 may be offset in the circumferential direction CD.

[0189] In this embodiment, the first inverter opening 921 and the second inverter opening 922 are positioned offset in the axial direction AD, so that the inverter lid portion 95 of the first inverter opening 921 and the inverter lid portion 95 of the second inverter opening 922 are positioned offset in the axial direction AD. The configuration in which the first inverter opening 921 and the second inverter opening 922 are positioned offset in the axial direction AD may be applied to the first embodiment. Furthermore, the inverter housing 90 does not necessarily have to be provided with the inverter lid accommodating portion 98, 198.

[0190] According to this embodiment, the first motor opening 721 and the second motor opening 722 are positioned offset in the axial direction AD. With this configuration, both motor openings 721, 722 are open, which allows outside air, such as propeller wind F1, flowing in the axial direction AD to easily flow in from one of the motor openings 721, 722, pass through the motor space 70a, and flow out the other. Passing through the motor space 70a, the outside air can easily cool heat-generating components, such as the motor 61. By allowing outside air to easily pass through the interior of the motor housing 70 in this way, the cooling effect of the heat-generating components can be improved.

[0191] Furthermore, the first inverter opening 921 and the second inverter opening 922 are positioned offset in the axial direction AD. With this configuration, both inverter openings 921, 922 are open, allowing outside air, such as propeller wind F1 flowing in the axial direction AD, to flow in through one of the inverter openings 921, 922, pass through the inverter space 90a, and easily flow out the other. Passing through the inverter space 90a, the outside air can easily cool drive-generating heat-generating components, such as the inverter high-voltage section 86 and the inverter low-voltage section 87. By allowing outside air to easily pass through the interior of the inverter housing 90 in this way, the cooling effect of the drive-generating heat-generating components can be improved.

[0192] <Other Embodiments> The disclosure of this specification is not limited to the exemplified embodiments. The disclosure encompasses the exemplified embodiments and modifications thereto by those skilled in the art. For example, the disclosure is not limited to the combinations of parts and elements shown in the embodiments, and can be implemented in various modifications. The disclosure can be implemented in various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure encompasses the omission of parts and elements from the embodiments. The disclosure encompasses the substitution or combination of parts and elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. The disclosed technical scope is defined by the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the claims.

[0193] In each of the above embodiments, a housing lid such as the motor lid 75 or the inverter lid 95 may be provided on at least one of the motor housing 70 and the inverter housing 90. In this case, at least one of the motor housing 70 and the inverter housing 90 corresponds to the drive housing.

[0194] In each of the above embodiments, the housing lid does not have to be detached from the drive housing when the housing opening is opened. That is, the housing lid does not have to be detachable from the drive housing. For example, in the first embodiment, a pivotal support that pivotally supports the motor lid 75 may be provided on the motor housing 70. In this configuration, when the motor lid holder 76 releases the motor lid 75 from its hold, the motor lid 75 rotates and transitions to the open state.

[0195] In each of the above embodiments, the housing lid may be configured to be able to transition from the closed state to the open state and then return from the open state to the closed state again.

[0196] In each of the above embodiments, a labyrinth portion forming a labyrinth passage may be provided as a foreign matter regulating portion such as the motor ventilation filter 73a. The labyrinth passage is a bent passage. The labyrinth portion is provided so that the labyrinth passage leads to the motor ventilation opening 73. For example, the labyrinth portion is provided outside the motor ventilation opening 73. In this configuration, even if foreign matter enters the labyrinth passage along with the outside air, the labyrinth passage prevents the foreign matter from reaching the motor ventilation opening 73.

[0197] In each of the above embodiments, the housing lid may be opened in any manner. For example, in the above first embodiment, the lid opening process may open the motor lid 75 for at least one of the first motor opening 721 and the second motor opening 722. Furthermore, the lid opening process may open the inverter lid 95 for at least one of the first inverter opening 921 and the second inverter opening 922. Furthermore, the lid opening process may open the inverter lid 95 for at least one of the first inverter device 801 and the second inverter device 802. Additionally, the lid opening process may open at least one of the motor lid 75 and the inverter lid 95.

[0198] In each of the above embodiments, the housing opening may be provided in any manner in the drive housing. For example, it is sufficient that the drive housing is provided with at least one of the motor opening 72 and the inverter opening 92. In other words, of the motor opening 72 and the inverter opening 92, the drive housing may be provided with only the motor opening 72 or only the inverter opening 92.

[0199] In each of the above embodiments, the flight control device 40 may acquire the fact that the housing lid has been opened in any manner. For example, in the above third embodiment, the flight control device 40 may use any sensor detection signal as long as it can determine that the motor lid 75 or the inverter lid 95 is in the open state, or it may not use a sensor detection signal. For example, an airflow sensor that detects the airflow through the motor opening 72 or the inverter opening 92 may be provided in the motor device 60 or the inverter device 80. The flight control device 40 determines that the motor lid 75 or the inverter lid 95 has transitioned to the open state if the airflow rate increases suddenly. Furthermore, the flight control device 40 does not have to acquire the fact that the housing lid has been opened.

[0200] In each of the above embodiments, the release temperature for determining whether to transition a lid holding portion such as the motor lid holding portion 76 to the released state and the permission temperature for determining whether to perform the EPU permission process may be set to different temperatures. Also, the release shape temperature for causing a release deformation portion such as the motor deformation portion 176a to deform a lid holding portion to the released state may be set to different temperatures from the first temperature threshold T1 for determining whether a high temperature abnormality has occurred in the driving heat generating portion.

[0201] In each of the above embodiments, the housing vents, such as the motor vent 73, may be provided in any manner in the drive housing. For example, the housing vents may be provided in the housing lid. In this configuration, it is preferable that the foreign object control unit, such as the motor vent filter 73a, is provided so as not to cover the housing opening when the housing lid is open. Furthermore, the housing vents do not have to be provided in the drive housing.

[0202] In each of the above embodiments, the propulsion device 100 may have both a cover holder that can be controlled by the flight control device 40 and a cover holder that cannot be controlled by the flight control device 40. For example, the propulsion device 100 may have both the motor cover holder 76 or the inverter cover holder 96 of the first embodiment and the motor cover holder 176 or the inverter cover holder 196 of the third embodiment.

[0203] In each of the above embodiments, at least a part of the programs stored in the memories 43 and 83 may be rewritten via wireless communication such as OTA. OTA is an abbreviation for Over the Air.

[0204] In each of the above embodiments, at least one of the inverter control unit 81 and the flight control device 40 may perform flight control processing. In this configuration, at least one of the inverter control unit 81 and the flight control device 40 corresponds to the propulsion control device. For example, in a configuration in which the inverter control unit 81 controls the motor holding and driving unit 77 and the inverter holding and driving unit 97, at least the inverter control unit 81 corresponds to the propulsion control device. In this configuration, when a re-flight prohibition process is performed, it is preferable that information indicating that the eVTOL 10 is prohibited from re-flighting is input from the inverter control unit 81 to the flight control device 40.

[0205] The propulsion control program may be included in at least one of the programs 44 and 84. Furthermore, at least one processing unit that executes the propulsion control program may include at least one of the processors 42 and 82.

[0206] In each of the above embodiments, the vertical take-off and landing aircraft on which the flight control device 40 is mounted may be an electrically operated vertical take-off and landing aircraft in which at least one EPU 50 drives at least one propeller 20. For example, a configuration in which one propeller 20 is driven by multiple EPUs 50, or a configuration in which one EPU 50 drives multiple propellers 20, may be used.

[0207] In each of the above embodiments, the air vehicle on which EPU 50 is mounted does not have to be a vertical take-off and landing aircraft as long as it is electrically powered. For example, the air vehicle may be an electric aircraft capable of take-off and landing with a taxiing motion. Furthermore, the air vehicle may be a rotary-wing aircraft or a fixed-wing aircraft. The air vehicle may also be an unmanned air vehicle without a crew member on board. An unmanned air vehicle may or may not have a crew member cabin 14. A pilot may also remotely operate the air vehicle. eVTOL 10 may be referred to as a manned air vehicle as long as it is capable of carrying a person.

[0208] In each of the above embodiments, the moving body on which the EPU 50 is mounted does not have to be an aircraft as long as it can move by rotation of a rotating body. For example, the moving body may be a vehicle, a ship, a construction machine, or an agricultural machine. For example, if the moving body is a vehicle or a construction machine, the rotating body may be a wheel for movement, and the output shaft may be an axle. If the moving body is a ship, the rotating body may be a screw propeller for propulsion, and the output shaft may be a propeller shaft.

[0209] In each of the above embodiments, the flight control device 40 and the inverter control unit 81 are provided by a control system including at least one computer. The control system includes at least one processor that is hardware. If this processor is referred to as a hardware processor, the hardware processor can be provided by the following (i), (ii), or (iii):

[0210] (i) A hardware processor may be a hardware logic circuit. In this case, the computer is provided by a digital circuit including a large number of programmed logic units (gate circuits). The digital circuit may include a memory that stores at least one of a program and data. The computer may be provided by an analog circuit. The computer may be provided by a combination of a digital circuit and an analog circuit.

[0211] (ii) The hardware processor may be at least one processor core that executes a program stored in at least one memory. In this case, a computer is provided by at least one memory and at least one processor core. The processor core is referred to as a CPU, for example. The memory is also referred to as a storage medium. The memory is a non-transitory, tangible storage medium that non-temporarily stores "at least one of a program and data" that can be read by the processor.

[0212] (iii) The hardware processor may be a combination of (i) above and (ii) above, where (i) and (ii) are located on different chips or on a common chip.

[0213] That is, at least one of the means and functions provided by the flight control device 40 and the inverter control unit 81 can be provided by hardware only, software only, or a combination thereof.

[0214] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0215] (Technical Idea 1) A propulsion system (30) for propelling a moving body (10), comprising: a motor (61) that drives to propel the moving body; a drive heat generating portion (61, 86, 87) that generates heat as the motor is driven; a drive housing (70, 90) that houses the drive heat generating portion; a housing lid portion (75, 95) that is provided so as to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing; a lid holding portion (76, 96, 176, 196) that holds the housing lid in a closed state that covers the housing opening; and a lid release portion (77, 97, 176, 196, S105) that releases the hold of the housing lid by the lid holding portion when a high temperature abnormality occurs, including when the temperature of the drive heat generating portion reaches a predetermined temperature (T1).

[0216] (Technical Idea 2) The lid release unit is a propulsion system described in Technical Idea 1, which has: a holding drive unit (77, 97) that drives to displace the lid holding unit; and a release execution unit (S105) that drives the holding drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases its hold on the housing lid unit when the high temperature abnormality occurs.

[0217] (Technical Idea 3) In the propulsion system described in Technical Idea 2, when the temperature of the drive heat generating part reaches a predetermined release temperature (T1), the release execution part determines that the high temperature abnormality has occurred and drives the holding drive part so that the lid holding part enters the released state.

[0218] (Technical Idea 4) A propulsion system according to Technical Idea 3, further comprising a current limiting unit (S202) that limits the motor current of the motor when the temperature of the driving heat generating unit reaches a predetermined limit temperature (T2), and the release temperature is a temperature higher than the limit temperature.

[0219] (Technical Idea 5) A propulsion system described in any one of Technical Ideas 1 to 4, wherein the lid release portion has a release deformation portion (176a, 196a) that is included in at least a part of the lid holding portion and that deforms due to the heat of the driving heat generating portion caused by the occurrence of the high temperature abnormality, thereby deforming the lid holding portion into a release shape that releases the holding of the housing lid portion.

[0220] (Technical Idea 6) A propulsion system according to Technical Idea 5, wherein the release deformation portion is formed to deform the lid holding portion into the release shape when the temperature of the driving heat generating portion reaches a predetermined release shape temperature (T1).

[0221] (Technical Idea 7) A propulsion system according to Technical Idea 6, further comprising a current limiting unit (S202) that limits the motor current of the motor when the temperature of the driving heat generating unit reaches a predetermined limit temperature (T2), and the release shape temperature is a temperature higher than the limit temperature.

[0222] (Technical Idea 8) A propulsion system described in any one of Technical Ideas 1 to 7, comprising the housing openings: a first opening (721, 921) provided in a position where at least a portion of the drive heat generating portion can be exposed to the outside of the drive housing; and a second opening (722, 922) provided in a position where at least a portion of the drive heat generating portion can be exposed to the outside of the drive housing and shifted in the axial direction (AD) of the motor relative to the first opening; and the housing lid portion, lid holding portion, and lid release portion are provided in the first opening and the second opening, respectively.

[0223] (Technical Idea 9) A propulsion system according to any one of Technical Ideas 1 to 8, wherein the motor is included in the drive heat-generating portion and is exposed to the outside through the housing opening when the lid release portion releases the retention of the housing lid portion.

[0224] (Technical Idea 10) A propulsion system described in any one of Technical Ideas 1 to 9, wherein the driving heat generating portion is arranged so as to be exposed to the outside from the housing opening when the lid release portion releases the retention of the housing lid portion, and has a control circuit portion (87) for controlling the driving of the motor.

[0225] (Technical Idea 11) A propulsion system according to any one of Technical Ideas 1 to 10, further comprising a drive stop unit (S110) that stops driving the motor if the high temperature abnormality continues even after the lid release unit releases the hold of the housing lid unit.

[0226] (Technical Idea 12) The moving body is an aircraft (10) that flies by being driven by the motor, and the propulsion system is described in any one of Technical Ideas 1 to 11, and is equipped with a takeoff restriction unit (S109) that restricts the takeoff of the aircraft when the lid release unit releases the hold of the housing lid unit.

[0227] (Technical Idea 13) A propulsion system according to any one of Technical Ideas 1 to 12, comprising: a housing vent (73, 93) for passing gas into the internal space (70a, 90a) of the drive housing; and a foreign object control section (73a, 93a) that does not control foreign objects from entering the internal space through the housing opening, but controls foreign objects from entering the internal space through the housing vent.

[0228] (Technical Idea 14) A propulsion control device (40) for controlling a propulsion system (30) having: a motor (61) that drives to propel a moving body (10); a drive heat generating part (61, 86, 87) that generates heat as the motor is driven; a drive housing (70, 90) that houses the drive heat generating part; a housing lid part (75, 95) that is provided so as to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing; a lid holding part (76, 96, 176, 196) that holds the housing lid part in a closed state that covers the housing opening; and a holding drive part (77, 97) that drives to displace the lid holding part, the propulsion control device (40) comprising: a high temperature determination part (S102) that determines whether or not a high temperature abnormality has occurred, including the temperature of the drive heat generating part reaching a predetermined temperature (T1); a release execution unit (S105) that drives the hold drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases its hold on the housing lid unit when the high temperature abnormality occurs.

[0229] (Technical Idea 15) A propulsion control program (44) for controlling a propulsion system (30) having: a motor (61) that drives to propel a moving body (10); a drive heat generating part (61, 86, 87) that generates heat as the motor is driven; a drive housing (70, 90) that houses the drive heat generating part; a housing lid part (75, 95) that is provided so as to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing; a lid holding part (76, 96, 176, 196) that holds the housing lid part in a closed state that covers the housing opening; and a holding drive part (77, 97) that drives to displace the lid holding part, the program comprising: causing at least one processing part (42) to determine whether or not a high temperature abnormality has occurred, including the temperature of the drive heat generating part reaching a predetermined temperature (T1) (S102); When the high temperature abnormality occurs, the propulsion control program drives the holding drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases its hold on the housing lid unit (S105).

Claims

1. A propulsion system (30) for propelling a moving body (10), comprising: a motor (61) that drives to propel the moving body; a drive heat generating section (61, 86, 87) that generates heat as the motor is driven; a drive housing (70, 90) that houses the drive heat generating section; a housing lid section (75, 95) that is provided to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing; a lid holding section (76, 96, 176, 196) that holds the housing lid in a closed state covering the housing opening; and a lid release section (77, 97, 176, 196, S105) that releases the hold of the housing lid by the lid holding section when a high temperature abnormality occurs, including the temperature of the drive heat generating section reaching a predetermined temperature (T1).

2. The propulsion system of claim 1, wherein the lid release unit has a hold drive unit (77, 97) that drives to displace the lid holding unit, and a release execution unit (S105) that drives the hold drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases its hold on the housing lid unit when the high temperature abnormality occurs.

3. A propulsion system as described in claim 2, wherein when the temperature of the driving heat generating portion reaches a predetermined release temperature (T1), the release execution portion determines that a high temperature abnormality has occurred and drives the holding driving portion so that the lid holding portion is in the released state.

4. A propulsion system as described in claim 3, further comprising a current limiting unit (S202) that limits a motor current of the motor when the temperature of the driving heat generating unit reaches a predetermined limit temperature (T2), and the release temperature is a temperature higher than the limit temperature.

5. A propulsion system as described in any one of claims 1 to 4, wherein the lid release portion has a release deformation portion (176a, 196a) that is included in at least a part of the lid holding portion and that deforms due to heat from the driving heat generating portion accompanying the occurrence of the high temperature abnormality, thereby deforming the lid holding portion into a release shape that releases the hold of the housing lid portion.

6. A propulsion system as described in claim 5, wherein the release deformation portion is formed to deform the lid holding portion into the release shape when the temperature of the driving heat generating portion reaches a predetermined release shape temperature (T1).

7. A propulsion system as described in claim 6, further comprising a current limiting unit (S202) that limits a motor current of the motor when the temperature of the driving heat generating unit reaches a predetermined limit temperature (T2), and the release shape temperature is a temperature higher than the limit temperature.

8. A propulsion system as described in claim 1 or 2, comprising: a first opening (721, 921) provided at a position where at least a portion of the driving heat generating portion can be exposed to the outside of the driving housing; and a second opening (722, 922) provided at a position where at least a portion of the driving heat generating portion can be exposed to the outside of the driving housing and offset in the axial direction (AD) of the motor from the first opening; and wherein the housing lid portion, the lid holding portion and the lid release portion are provided in the first opening and the second opening, respectively.

9. A propulsion system as described in claim 1 or 2, wherein the motor is included in the driving heat generating portion and is arranged so as to be exposed to the outside through the housing opening when the lid release portion releases the retention of the housing lid portion.

10. A propulsion system as described in claim 1 or 2, wherein the driving heat generating section is arranged so as to be exposed to the outside from the housing opening when the lid release section releases the retention of the housing lid section, and has a control circuit section (87) for controlling the driving of the motor.

11. A propulsion system as described in claim 1 or 2, further comprising a drive stop unit (S110) that stops the drive of the motor if the high temperature abnormality continues even after the lid release unit releases the hold of the housing lid unit.

12. The propulsion system of claim 1 or 2, wherein the moving body is an aircraft (10) that flies by being driven by the motor, and the propulsion system is provided with a takeoff restriction section (S109) that restricts the takeoff of the aircraft when the lid release section releases the retention of the housing lid section.

13. A propulsion system as described in claim 1 or 2, comprising: a housing vent (73, 93) for passing gas into the internal space (70a, 90a) of the drive housing; and a foreign object control section (73a, 93a) that does not control foreign objects from entering the internal space through the housing opening, but controls foreign objects from entering the internal space through the housing vent.

14. A propulsion control device (40) for controlling a propulsion system (30) having a motor (61) that drives to propel a moving body (10), a driving heat generating part (61, 86, 87) that generates heat as the motor is driven, a drive housing (70, 90) that houses the driving heat generating part, a housing lid part (75, 95) that is provided so as to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing, a lid holding part (76, 96, 176, 196) that holds the housing lid part in a closed state covering the housing opening, and a holding drive part (77, 97) that drives to displace the lid holding part, the propulsion control device (40) comprising: a high temperature determination part (S102) that determines whether or not a high temperature abnormality has occurred, including the temperature of the driving heat generating part reaching a predetermined temperature (T1); a release execution unit (S105) that drives the hold drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases its hold on the housing lid unit when the high temperature abnormality occurs.

15. A propulsion control program (44) for controlling a propulsion system (30) having a motor (61) that drives to propel a moving body (10), a driving heat generating part (61, 86, 87) that generates heat as the motor is driven, a drive housing (70, 90) that houses the driving heat generating part, a housing lid part (75, 95) that is provided so as to be able to open a housing opening (72, 721, 722, 92, 921, 922) of the drive housing, a lid holding part (76, 96, 176, 196) that holds the housing lid part in a closed state that covers the housing opening, and a holding drive part (77, 97) that drives to displace the lid holding part, the program comprising: causing at least one processing part (42) to determine whether or not a high temperature abnormality has occurred, including the temperature of the driving heat generating part reaching a predetermined temperature (T1) (S102); a propulsion control program for driving the holding drive unit to transition the lid holding unit to a release state (P2) in which the lid holding unit releases the hold of the housing lid unit when the high temperature abnormality occurs (S105);

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