aircraft

Abstract

Provided is an aircraft. The aircraft (10) has a rotor (18) and a rotor (20) driven by an electric motor (48), a PCU (42) that converts AC power output from a generator (40) into DC power, an inverter (50) that converts DC power supplied from the PCU (42) into AC power and outputs it to the electric motor (48), a DC wiring that connects the PCU (42) and the inverter (50), and an AC wiring that connects the inverter (50) and the electric motor (48), the AC wiring being arranged in a direction orthogonal to a direction in which rotation axes of the generator (40) and a gas turbine (38) extend. Accordingly, thrust can be ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to an aircraft. BACKGROUND

[0002] A multi-rotor electric aircraft is disclosed in the specification of U.S. Patent Application Publication No. 2020 / 0115045. SUMMARY

[0003] The multi-rotor electric aircraft disclosed in the above-mentioned U.S. Patent Application Publication No. 2020 / 0115045 has a plurality of electric motors that respectively drive a plurality of rotors. Electric power is supplied from an electric energy source to the electric motors. The electric energy source has a motor, a generator, an electric storage device, and an energy management device.

[0004] In the case where fragments are scattered due to breakage of a rotor of the motor or the generator, the wiring that connects a part of the electric motors and the electric energy source can be damaged, short-circuited by the scattered fragments. In this case, there is a technical problem that electric power cannot be supplied to the other electric motors either, and thus thrust cannot be ensured.

[0005] An object of the present application is to solve the above-mentioned technical problem.

[0006] A mode of the present application is an aircraft having a generator, a motor, an electric motor, a rotor, a power control unit, an inverter, a direct current wiring, and an alternating current wiring, wherein the generator generates electric power; the motor drives the generator; the electric motor operates by alternating current electric power; the rotor is driven by the electric motor to generate thrust; the power control unit converts alternating current electric power output from the generator into direct current electric power; the inverter converts direct current electric power supplied from the power control unit into alternating current electric power, and outputs it to the electric motor; the direct current wiring connects the power control unit and the inverter; the alternating current wiring connects the inverter and the electric motor, and the alternating current wiring is disposed in a direction orthogonal to a direction in which a rotation axis of the generator extends, and the direct current wiring is not disposed, with respect to the generator, or the alternating current wiring is disposed in a direction orthogonal to a direction in which a rotation axis of the motor extends, and the direct current wiring is not disposed, with respect to the motor.

[0007] According to the present application, even in the case where fragments are scattered due to breakage of a rotor of the motor or the generator, thrust can be ensured.

[0008] The above objects, features and advantages will be easily understood from the following description of the embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a schematic view of an aircraft.

[0010] Figure 2 is a schematic view showing the structure of an electric power supply system.

[0011] Figure 3 is a view showing the wiring structure in an aircraft. DETAILED DESCRIPTION

[0012] [First Embodiment]

[0013] [Structure of Aircraft]

[0014] Figure 1 is a schematic view of an aircraft 10. The aircraft 10 of the present embodiment is an electric vertical takeoff and landing aircraft (eVTOL aircraft). The aircraft 10 drives a rotor by an electric motor. The aircraft 10 generates vertical direction thrust and horizontal direction thrust by the rotor. In addition, the aircraft 10 is a hybrid aircraft. The aircraft 10 has a generator and a battery as a power source of the electric motor. In the aircraft 10, electric power generated by the generator is supplied to the electric motor. In a case where the electric power generated by the generator is insufficient with respect to the required electric power, electric power stored in the battery is supplied to the electric motor.

[0015] The aircraft 10 has a fuselage 12. A cockpit, a cabin, and the like are provided in the fuselage 12. A pilot is seated in the cockpit, and the aircraft 10 is manipulated. A passenger or the like is seated in the cabin. The aircraft 10 can also be automatically manipulated.

[0016] The aircraft 10 has a front wing 14 and a rear wing 16. In a case where the aircraft 10 moves in a forward direction, the front wing 14 and the rear wing 16 each generate lift.

[0017] The aircraft 10 has a boom 17L and a boom 17R. The boom 17L and the boom 17R are fixed to the front wing 14 and the rear wing 16. The boom 17L and the boom 17R extend in a front-rear direction of the aircraft 10. The boom 17L is provided at a position on a left side of a center of gravity G of the fuselage 12, and the boom 17R is provided at a position on a right side of the center of gravity G of the fuselage 12.

[0018] The aircraft 10 has eight VTOL rotors 18. The eight VTOL rotors 18 are a rotor 18La, a rotor 18Lb, a rotor 18Lc, a rotor 18Ld, a rotor 18Ra, a rotor 18Rb, a rotor 18Rc, and a rotor 18Rd.

[0019] The rotor 18La, the rotor 18Lb, the rotor 18Lc, and the rotor 18Ld are mounted to the boom 17L. The rotor 18Ra, the rotor 18Rb, the rotor 18Rc, and the rotor 18Rd are mounted to the boom 17R.

[0020] The rotation axis of each VTOL rotor 18 extends in the up-and-down direction of the fuselage 12. Each VTOL rotor 18 controls the thrust by adjusting the rotation speed of the rotor and the pitch angle of the blade. Each VTOL rotor 18 is used at the time of vertical takeoff, at the time of transition from vertical takeoff to cruising, at the time of transition from cruising to vertical landing, at the time of vertical landing, at the time of hovering in the air, and the like. In addition, each VTOL rotor 18 is used at the time of attitude control.

[0021] The ascending thrust is generated by controlling the thrust of each VTOL rotor 18. The ascending thrust refers to the thrust in the vertical direction. The roll moment, the pitch moment, and the yaw moment are exerted on the fuselage 12 by controlling the thrust of each VTOL rotor 18.

[0022] The aircraft 10 has two cruising rotors 20. The two cruising rotors 20 are the rotor 20L and the rotor 20R. The rotor 20L and the rotor 20R are mounted to the rear portion of the fuselage 12.

[0023] The rotation axis of each cruising rotor 20 extends in the front-and-rear direction of the fuselage 12. Each cruising rotor 20 controls the thrust by adjusting the rotation speed of the rotor and the pitch angle of the blade. Each cruising rotor 20 is used at the time of transition from vertical takeoff to cruising, at the time of cruising, at the time of transition from cruising to vertical landing, and the like.

[0024] The cruising thrust is generated by controlling the thrust of each cruising rotor 20. The cruising thrust refers to the thrust in the horizontal direction.

[0025] [Structure of electric power supply system]

[0026] Figure 2 is a schematic view that shows the structure of the electric power supply system 22.

[0027] The electric power supply system 22 has an electric power supply circuit 24, two electric power generation units 26, and four batteries 28. The electric power supply system 22 supplies electric power to four drive modules 30. The two electric power generation units 26 refer to a first electric power generation unit 26a and a second electric power generation unit 26b. The four drive modules 30 refer to a first drive module 30a, a second drive module 30b, a third drive module 30c, and a fourth drive module 30d.

[0028] The electric power supply circuit 24 has a first power transmission path 32 and a second power transmission path 34. The first power transmission path 32 supplies electric power from the first power generation unit 26a to the first drive module 30a and the second drive module 30b, respectively. The second power transmission path 34 supplies electric power from the second power generation unit 26b to the third drive module 30c and the fourth drive module 30d, respectively. In the present embodiment, the first power transmission path 32 is not connected to the second power transmission path 34, but a circuit connecting the first power transmission path 32 and the second power transmission path 34 together can be provided. In this case, a contactor is provided on the circuit, and by the contactor, the state of the first power transmission path 32 being connected to the second power transmission path 34 and the state of the first power transmission path 32 and the second power transmission path 34 being cut off can be switched.

[0029] In addition to the electric power generated in each power generation unit 26, the electric power stored in each battery 28 is supplied to each drive module 30.

[0030] Each power generation unit 26 has a gas turbine 38, a generator 40, and a power control unit (hereinafter, referred to as PCU) 42. The gas turbine 38 drives the generator 40. By this, the generator 40 generates electric power. The PCU 42 converts the alternating-current electric power generated by the generator 40 into direct-current electric power and outputs it to the electric power supply circuit 24.

[0031] In a case where the gas turbine 38 is started, the PCU 42 converts the direct-current electric power supplied from the electric power supply circuit 24 into alternating-current and outputs it to the generator 40. By the electric power input from the PCU 42, the generator 40 operates, and thus the generator 40 drives the gas turbine 38.

[0032] The first drive module 30a and the third drive module 30c each have two drive units 44 and one converter 46. The second drive module 30b and the fourth drive module 30d each have three drive units 44. Each VTOL rotor 18 or each cruise rotor 20 is driven by each drive unit 44.

[0033] Each drive unit 44 has an electric motor 48 and an inverter 50. The electric motor 48 is a three-phase motor. Each VTOL rotor 18 is connected to an output shaft of each electric motor 48. Each cruise rotor 20 is connected to an output shaft of each electric motor 48. The inverter 50 has a semiconductor switching element such as an IGBT (Insulated Gate Bipolar Transistor). The inverter 50 converts the direct-current electric power supplied from the electric power supply circuit 24 into three-phase alternating-current electric power and outputs it to the electric motor 48.

[0034] The control of the semiconductor switching elements in the inverter 50 is performed by a controller (not shown). The controller is supplied with electric power from a low-voltage battery (not shown).

[0035] The converter 46 steps down the voltage of the direct-current electric power supplied from the electric power supply circuit 24 and outputs it to a device that operates by direct-current electric power. The device that operates by direct-current electric power is, for example, a cooling device that cools the PCU 42, the inverter 50, and the like. The electric power that has been stepped down in voltage by the converter 46 can also be supplied to the controller.

[0036] The battery 28 is connected to each drive module 30. The battery 28 is a high-voltage battery that is provided separately from the low-voltage battery. A cutoff device 52 is provided between each battery 28 and each drive module 30. Each cutoff device 52 has a contactor 52a, a contactor 52b, and a pre-charge circuit 52c. The contactor 52a is provided on a positive line that connects each battery 28 and each drive module 30 together. The contactor 52b is provided on a negative line that connects each battery 28 and each drive module 30 together. The pre-charge circuit 52c is provided in parallel with the contactor 52b. The pre-charge circuit 52c has a contactor 52d and a resistor 52e. A current sensor 54 is provided on the negative line that connects each battery 28 and each drive module 30 together.

[0037] Each cutoff device 52 switches between an on state and an off state between each battery 28 and each drive module 30. The on state is a state in which the flow of current is not cut off by the cutoff device 52 and current flows. The off state is a state in which the flow of current is cut off by the cutoff device 52.

[0038] Each cutoff device 52 can also have only the contactor 52b and the pre-charge circuit 52c. The pre-charge circuit 52c can also be provided in parallel with the contactor 52a. In this case, each cutoff device 52 can also have only the contactor 52a and the pre-charge circuit 52c. Furthermore, the electric power supply system 22 can also not have the battery 28 and the cutoff device 52.

[0039] The electric power supply circuit 24 has a cutoff device 56. The cutoff device 56 is provided between the power generation unit 26 and the first power transmission path 32. The cutoff device 56 has a contactor 56a and a contactor 56b. The contactor 56a is provided on a positive line that connects the power generation unit 26 and the first power transmission path 32 together. The contactor 56b is provided on a negative line that connects the power generation unit 26 and the first power transmission path 32 together. A current sensor 58 is provided between the contactor 56a and the first power transmission path 32. The cutoff device 56 can also have only one of the contactor 56a and the contactor 56b.

[0040] The switching device 56 switches between the on state and the off state between each power generating unit 26 and the first power transmission path 32.

[0041] The electric power supply circuit 24 has two switching devices 60. Each switching device 60 is provided between each drive module 30 and the first power transmission path 32. Each switching device 60 has a contactor 60a and a contactor 60b. Each contactor 60a is provided on a positive electrode wiring that connects each drive module 30 and the first power transmission path 32 together. Each contactor 60b is provided on a negative electrode wiring that connects each drive module 30 and the first power transmission path 32 together. A current sensor 62 is provided between each contactor 60a and the first power transmission path 32.

[0042] Each switching device 60 can have only one of the contactor 60a and the contactor 60b. In the case where the switching device 56 has only the contactor 56a, it is preferable that each switching device 60 has only the contactor 60b. In the case where the switching device 56 has only the contactor 56b, it is preferable that each switching device 60 has only the contactor 60a.

[0043] Each switching device 60 switches between the on state and the off state between each drive module 30 and the first power transmission path 32.

[0044] The electric power supply circuit 24 has a switching device 64. The switching device 64 is provided between the power generating unit 26 and the second power transmission path 34. The switching device 64 has a contactor 64a and a contactor 64b. The contactor 64a is provided on a positive electrode wiring that connects the power generating unit 26 and the second power transmission path 34 together. The contactor 64b is provided on a negative electrode wiring that connects the power generating unit 26 and the second power transmission path 34 together. A current sensor 66 is provided between the contactor 64a and the second power transmission path 34. The switching device 64 can have only one of the contactor 64a and the contactor 64b.

[0045] The switching device 64 switches between the on state and the off state between each power generating unit 26 and the second power transmission path 34.

[0046] The electric power supply circuit 24 has two switching devices 68. Each switching device 68 is provided between each drive module 30 and the second power transmission path 34. Each switching device 68 has a contactor 68a and a contactor 68b. Each contactor 68a is provided on a positive electrode wiring that connects the power generating unit 26 and the second power transmission path 34 together. Each contactor 68b is provided on a negative electrode wiring that connects the power generating unit 26 and the second power transmission path 34 together. A current sensor 70 is provided between each contactor 68a and the second power transmission path 34.

[0047] Each of the cut-off devices 68 can have only one of the contactors 68a and 68b. In the case where the cut-off device 64 has only the contactor 64a, it is preferable that each of the cut-off devices 68 has only the contactor 68b. In the case where the cut-off device 64 has only the contactor 64b, it is preferable that each of the cut-off devices 68 has only the contactor 68a.

[0048] Each of the cut-off devices 68 switches between the on state and the off state between each of the drive modules 30 and the second power transmission path 34.

[0049] A diode 71 is provided between the contactor 60a of each of the cut-off devices 60 and the battery 28. The anode of each of the diodes 71 is connected to the contactor 60a side, and the cathode is connected to each of the battery 28 sides. With each of the diodes 71, the supply of electric power from the first power transmission path 32 to each of the batteries 28 is permitted. With each of the diodes 71, the supply of electric power from each of the batteries 28 to the first power transmission path 32 is prevented. Each of the batteries 28 is charged by the electric power supplied from the first power generation unit 26a. In addition, in the case where the first power transmission path 32 is short-circuited, the electric power of each of the batteries 28 is prevented from flowing to the first power transmission path 32. As a result, even in the case where the first power transmission path 32 is short-circuited, electric power can be supplied from each of the batteries 28 to the drive units 44 and the inverters 46 in each of the drive modules 30.

[0050] A transistor 72 is provided in parallel with each of the diodes 71. In the case where the transistor 72 is on, electric power is supplied from each of the batteries 28 to the first power transmission path 32, bypassing the diode 71. With the electric power supplied from each of the batteries 28, the electric generator 40 can be operated to start the operation of the gas turbine 38.

[0051] In addition, a diode 74 is provided between the contactor 68a of each of the cut-off devices 68 and the battery 28. The anode of each of the diodes 74 is connected to the contactor 68a, and the cathode is connected to each of the battery 28. With each of the diodes 74, the supply of electric power from the second power transmission path 34 to each of the batteries 28 is permitted. With each of the diodes 74, the supply of electric power from each of the batteries 28 to the second power transmission path 34 is prevented. Each of the batteries 28 is charged by the electric power supplied from the second power generation unit 26b. In addition, in the case where the second power transmission path 34 is short-circuited, the electric power of each of the batteries 28 is prevented from flowing to the second power transmission path 34. As a result, even in the case where the second power transmission path 34 is short-circuited, electric power can be supplied from each of the batteries 28 to the drive units 44 and the inverters 46 in each of the drive modules 30.

[0052] A transistor 76 is provided in parallel with each of the diodes 74. In the case where the transistor 76 is on, electric power is supplied from each of the batteries 28 to the second power transmission path 34, bypassing the diode 74. With the electric power supplied from each of the batteries 28, the electric generator 40 can be operated to start the operation of the gas turbine 38.

[0053] [Wire arrangement in an aircraft]

[0054] Figure 3 is a view showing a wire arrangement in the aircraft 10. Figure 3 The thick single-dot chain line indicates a direct-current wire, and the thick solid line indicates an alternating-current wire.

[0055] The alternating-current electric power generated by each generator 40 is converted into direct-current electric power by each PCU 42. The converted direct-current electric power is delivered to the electric power supply circuit 24 through a direct-current wire.

[0056] An inverter 50 that controls an electric motor 48 that drives each VTOL rotor 18 is provided in the boom 17L or the boom 17R. The direct-current electric power delivered to the electric power supply circuit 24 is delivered to each inverter 50 through a direct-current wire. This direct-current wire passes through the inside of the fore wing 14, the boom 17L, and the boom 17R. The alternating-current electric power output from each inverter 50 is delivered to each electric motor 48 through an alternating-current wire. This alternating-current wire passes through the inside of the boom 17L and the boom 17R.

[0057] An inverter 50 that controls an electric motor 48 that drives each cruise rotor 20 is provided in the fuselage 12. The direct-current electric power delivered to the electric power supply circuit 24 is delivered to each inverter 50 through a direct-current wire. This direct-current wire passes through the inside of the fuselage 12. The alternating-current electric power output from each inverter 50 is delivered to each electric motor 48 through an alternating-current wire. This alternating-current wire passes through the inside of the fuselage 12.

[0058] As shown in Figure 3 Each generator unit 26 is arranged in the fuselage 12. Each generator unit 26 is arranged at a position that is rearward of the center of gravity G of the fuselage 12 in the fore-aft direction. The gas turbine 38, the generator 40, and the PCU 42 are arranged in this order from rearward to forward in the fore-aft direction of the fuselage 12 in each generator unit 26.

[0059] The rotor of each gas turbine 38 rotates about a rotation axis that extends in parallel to the fore-aft direction of the fuselage 12. The rotor of each generator 40 rotates about a rotation axis that extends in parallel to the fore-aft direction of the fuselage 12.

[0060] Figure 3The region A indicated by a thin dotted line in the middle indicates a region orthogonal to the rotational axis of each gas turbine 38 and orthogonal to the rotational axis of the generator 40. The rotor 18Ld and the rotor 18Rd in the VTOL rotor 18 are disposed behind the region A. The rotor 20L and the rotor 20R that are the cruising rotors 20 are disposed behind the region A. The electric motors 48 that drive the rotor 18Ld, the rotor 18Rd, the rotor 20L, and the rotor 20R, respectively, are also disposed behind the region A. In other words, on the opposite side of each gas turbine 38 on which the PCU 42 is disposed, the electric motors 48 that drive the rotor 18Ld, the rotor 18Rd, the rotor 20L, and the rotor 20R, respectively, are disposed. In addition, it can also be said that on the opposite side of each generator 40 on which the PCU 42 is disposed, the electric motors 48 that drive the rotor 18Ld, the rotor 18Rd, the rotor 20L, and the rotor 20R, respectively, are disposed. On the other hand, the inverters 50 that drive these electric motors 48 are disposed in front of the region A.

[0061] Accordingly, in the region A, the alternating-current wiring is disposed, but the direct-current wiring is not disposed. It is assumed that in the case where the rotor of the gas turbine 38 or the generator 40 is broken, the fragments are likely to be scattered in the range of the region A. In this case, the scattered fragments can cut the alternating-current wiring disposed in the region A, and cause the alternating-current wiring to be damaged or short-circuited.

[0062] The electric power supply system 22 has a not-shown short-circuit detection device that detects that the alternating-current wiring connecting each inverter 50 and each electric motor 48 is short-circuited. In the case where the alternating-current wiring is short-circuited, the inverter 50 cuts off the short-circuited alternating-current wiring from the electric power supply circuit 24.

[0063] [Effects]

[0064] In the aircraft 10, it is required that even in the case where the rotors of a part of the VTOL rotors 18 and the cruising rotors 20 lose thrust, the remaining rotors can ensure the thrust. Therefore, it is required that even in the case where a part of the wiring that supplies the electric power from each electric power unit 26 to each electric motor 48 is short-circuited due to the rotor breakage of the gas turbine 38 or the generator 40, the supply of the electric power to the electric motor 48 can be maintained as much as possible.

[0065] The aircraft 10 of the present embodiment is such that the alternating-current wiring that connects the inverter 50 and the electric motor 48 together is disposed in the region A in which the fragments are likely to be scattered in the case where the rotor of the gas turbine 38 or the generator 40 is broken.

[0066] For example, as Figure 3As shown, in the case where the AC wiring connecting the inverter 50 and the electric motor 48 driving the rotor 18Rd is short-circuited, the inverter 50 cuts off the short-circuited AC wiring from the electric power supply circuit 24. The cut-off between the short-circuited AC wiring and the electric power supply circuit 24 is performed by a semiconductor switching element in the inverter 50. The semiconductor switching element can operate at a higher speed than a contactor or the like. Therefore, in the case where the AC wiring is cut off, the cut-off between the AC wiring and the electric power supply circuit 24 can be performed by the semiconductor switching element in a very short time. Accordingly, the electric power supply system 22 can maintain the supply of electric power to the other electric motors 48 and the converter 46.

[0067] It is considered that the short-circuited wiring is cut off from the electric power supply circuit 24 by a fuse, a contactor, or the like. However, since the inverter 50 is configured by a switching element, the inverter 50 can operate at a higher speed than a fuse, a contactor, or the like. Therefore, the time from the detection of the short-circuit of the wiring to the cut-off between the short-circuited wiring and the electric power supply circuit 24 can be shortened.

[0068] Further, the present application is not limited to the above-described embodiments, and various structures can be employed within the scope of the gist of the present application.

[0069] 〔Invention that can be achieved according to the embodiments〕

[0070] The invention that can be achieved according to the above-described embodiments is described below.

[0071] An aircraft (10) having a generator (40), an engine (38), an electric motor (48), a rotor (18, 20), a power supply control unit (42), an inverter (50), a DC wiring, and an AC wiring, wherein the generator generates electric power; the engine drives the generator; the electric motor operates by AC electric power; the rotor is driven by the electric motor and generates thrust; the power supply control unit converts AC electric power output from the generator into DC electric power; the inverter converts DC electric power supplied from the power supply control unit into AC electric power and outputs the same to the electric motor; the DC wiring connects the power supply control unit and the inverter together; and the AC wiring connects the inverter and the electric motor together, and the AC wiring is disposed in a direction orthogonal to a direction in which a rotation axis of the generator extends, and the DC wiring is not disposed, with respect to the generator, or the AC wiring is disposed in a direction orthogonal to a direction in which a rotation axis of the engine extends, and the DC wiring is not disposed, with respect to the engine. Accordingly, even in the case where rotor breakage occurs in the engine or the generator, thrust can be ensured.

[0072] In the above-described aircraft, the electric motor can be disposed on the side opposite to the side of the electric generator or the engine on which the power supply control unit is disposed, in the direction in which the rotating shaft of the electric generator extends or in the direction in which the rotating shaft of the engine extends. According to this, it is possible to ensure the thrust even in the case where the engine or the electric generator has a rotor breakage.

Claims

1. An aircraft (10) comprising a generator (40), an engine (38), an electric motor (48), rotors (18, 20), a power control unit (42), an inverter (50), DC wiring and AC wiring, wherein, The generator produces electrical power; The engine drives the generator; The electric motor operates using alternating current power. The rotor is driven by the electric motor to generate thrust; The power control unit converts the AC power output from the generator into DC power. The inverter converts the DC power supplied by the power control unit into AC power and outputs it to the electric motor. The DC wiring connects the power control unit and the inverter; The AC wiring connects the inverter and the electric motor. Its features are, The AC wiring is configured in a region orthogonal to the rotation axis of the generator, but the DC wiring is not configured therein; or, the AC wiring is configured in a region orthogonal to the rotation axis of the engine, but the DC wiring is not configured therein.

2. The aircraft according to claim 1, characterized in that, The electric motor is positioned on the side opposite to the side of the generator or the engine where the power control unit is located, in the direction in which the generator's rotating shaft extends or the engine's rotating shaft extends.

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