Electrically-driven helicopter

Abstract

To provide an electrically-driven rotary wing aircraft having a transmission mechanism for which a mode is selectable from a plurality of modes and which is capable of controlling both rotation speed and rotor pitch in accordance with each mode.SOLUTION: An electrically-driven rotary wing aircraft includes: a first output shaft; a main rotor system arranged on the first output shaft and having a main rotor and a rotor blade rotatable with respect to the axis center of the first output shaft; a power shaft that transmits power to the first output shaft; an electrically-driven motor system that is arranged on the power shaft and drives the main rotor system; and a flight control device that is connected to the electrically-driven motor system, and controls the electrically-driven motor system so as to keep a rotation speed of the first output shaft at a rotation speed corresponding to each mode and to keep a rotor pitch of the rotor blade at a rotor pitch corresponding to each mode.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an electric rotorcraft. [Background technology]

[0002] In recent years, in parallel with the electrification of automobiles, the electrification of small aircraft has been attracting attention. For example, small, electrically powered aircraft capable of vertical take-off and landing can be powered by electric motors without using fossil fuels. Since electric, vertical take-off and landing small aircraft do not use fossil fuels, they emit less CO2 and require less energy refueling than aircraft with internal combustion engines. The system is easy to operate, the entire system can be made compact, and it is easy to operate and quiet. For example, a helicopter is one of the small aircraft that can take off and land vertically. An electric helicopter is called, for example, an electric helicopter or an electric rotorcraft.

[0003] For example, Patent Documents 1 to 4 disclose configuration and control methods for electric helicopters. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 8,931,732 [Patent Document 2] U.S. Patent No. 9,169,027 [Patent Document 3] International Publication No. 2016 / 009824 [Patent Document 4] International Publication No. 2015 / 146608 Summary of the Invention [Problem to be solved by the invention]

[0005] One of the objectives of the present invention is to provide an electric rotorcraft in which the part corresponding to the internal combustion engine of an aircraft that uses a conventional internal combustion engine is replaced with a transmission mechanism that can select from a number of modes and can control both the rotation speed and rotor pitch according to each mode. [Means for solving the problem]

[0006] 1. An electric rotorcraft comprising: a first output shaft; a main rotor system provided on the first output shaft and having a main rotor and rotor blades rotatable about an axial center of the first output shaft; a power shaft transmitting power to the first output shaft; an electric motor system provided on the power shaft and driving the main rotor system; and a flight control device connected to the electric motor system and capable of selecting a first mode, a second mode, a third mode, and a fourth mode for flying an electric rotorcraft, the flight control device controlling the electric motor system to maintain a rotation speed of the first output shaft at a rotation speed corresponding to each mode, and controlling a rotor pitch of the rotor blades to maintain a rotor pitch corresponding to each mode, wherein the first mode adjusts the rotation speed of the first output shaft to a first rotation speed corresponding to a flight speed when the electric rotorcraft is ascending or descending in accordance with a flight speed of the electric rotorcraft, and adjusts the rotor pitch of the rotor blades corresponding to the flight speed to a first rotor pitch corresponding to the flight speed when the electric rotorcraft is ascending or descending. a mode for flying the electric rotorcraft in a first flight state, and a second mode for adjusting a rotation speed of the first output shaft according to the flight speed to a second rotation speed such that an electric power for driving the electric rotorcraft according to the flight speed of the electric rotorcraft is a minimum electric power, and adjusting a rotor pitch of the rotor blades according to the flight speed to a second rotor pitch such that an electric power for driving the electric rotorcraft according to the flight speed of the electric rotorcraft is a minimum electric power. a mode for flying the electric rotorcraft in a second flight state, and the third mode includes adjusting a rotation speed of the first output shaft corresponding to the flight speed to a third rotation speed corresponding to a flight speed at which the electric rotorcraft is flown with a predetermined maximum surplus power, so that the flight speed of the electric rotorcraft becomes a flight speed at which the electric rotorcraft is flown with a predetermined maximum surplus power, and adjusting a rotor pitch of the rotor blades corresponding to the flight speed to a third rotor pitch corresponding to the flight speed at which the electric rotorcraft is flown with a predetermined maximum surplus power.a mode for flying the electric rotorcraft in a third flight state, and a fourth mode for flying the electric rotorcraft in a fourth flight state in which the rotation speed of the first output shaft according to the flight speed is adjusted to a fourth rotation speed that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170, and the rotor pitch of the rotor blades according to the flight speed is adjusted to a fourth rotor pitch that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170, thereby flying the electric rotorcraft in a fourth flight state in which noise generated by the rotation of the main rotor and the rotor blades is suppressed. Effect of the Invention

[0007] According to one embodiment of the present invention, it is possible to provide an electric rotorcraft in which the part corresponding to the internal combustion engine of an aircraft that uses a conventional internal combustion engine is replaced with a transmission mechanism that can select from a number of modes and can control both the rotation speed and rotor pitch according to each mode. [Brief description of the drawings]

[0008] [Figure 1] 1 is a plan view showing a configuration of an electric rotorcraft according to an embodiment of the present invention. FIG. [Diagram 2] 1 is a block diagram showing a configuration of an electric rotorcraft according to an embodiment of the present invention. FIG. [Diagram 3] 1 is a block diagram showing a configuration of an electric rotorcraft according to an embodiment of the present invention. FIG. [Figure 4] FIG. 2 is a state transition diagram showing flight modes of the electric rotorcraft according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention can be implemented in many different aspects, and should not be interpreted as being limited to the description of the embodiments exemplified below. In addition, in order to make the explanation clearer, the width, thickness, shape, configuration, etc. of each part may be shown diagrammatically compared to the actual aspect, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, in this specification and each figure, elements similar to those described above with respect to the previous figures may be given the same symbols (or symbols with a, b, A, B, etc. added after the numbers) and detailed explanations may be omitted as appropriate. Note that the letters "first" and "second" added to each element are convenient labels used to distinguish each element, and have no further meaning unless otherwise specified.

[0010] In the specification and claims of this application (hereinafter referred to as "this specification etc."), an electric rotorcraft according to an embodiment of the present invention is, for example, a high-speed hybrid rotorcraft, a contra-rotating rotorcraft, or a coaxial-rotating rotorcraft. Furthermore, the electric rotorcraft according to an embodiment of the present invention may be either a manned or unmanned configuration. In this specification etc., the electric rotorcraft will be described taking a manned electric helicopter as an example. <1. First embodiment> <1-1. Configuration of electric rotorcraft 10>

[0011] An electric rotorcraft 10 according to an embodiment of the present invention will be described with reference to Figs. 1 to 3. Fig. 1 is a plan view showing the configuration of electric rotorcraft 10 according to an embodiment of the present invention. Fig. 2 is a block diagram showing the configuration of electric rotorcraft 10 according to an embodiment of the present invention. Fig. 3 is a block diagram showing the configuration of electric rotorcraft 10 according to an embodiment of the present invention. The configuration of electric rotorcraft 10 shown in Figs. 1 to 3 is just one example, and the configuration of electric rotorcraft 10 is not limited to the configuration shown in Figs. 1 to 3.

[0012] 1, the electric rotorcraft 10 includes an electric rotorcraft body 20, a main rotor system 30, and a tail rotor system 40. The electric rotorcraft body 20 supports the main rotor system 30 and the tail rotor system 40. The electric rotorcraft 10 also has therein an electric motor system 100 having a first motor 100A, a second motor 100B, a first motor control device 102A, and a second motor control device 102B, a bulkhead 104, a power control system 110 having a first battery management system 110A, a second battery management system 110B, a first battery 120A, a second battery 120B, and a third battery 120C, a flight control device 130, a flight control device 140, a reduction gear 150, a drive shaft 152, a main rotor shaft 154, a tail rotor shaft 156, a main rotor 160, rotor blades 170, a main rotor control device, a tail rotor 180, and a tail rotor control device.

[0013] In this specification and the like, the drive shaft 152 may be referred to as a power shaft or a first power shaft, the main rotor shaft 154 may be referred to as an output shaft or a first output shaft, and the tail rotor shaft 156 may be referred to as an output shaft or a second output shaft. Also, in this specification and the like, the electric motor system 100 may be referred to as a transmission mechanism. Also, the transmission mechanism may include the drive shaft 152 and may include the power control system 110.

[0014] The main rotor system 30 includes a main rotor 160, a plurality of rotor blades 170 provided on the main rotor 160, and a main rotor control device 172. The tail rotor system 40 includes a tail rotor 180 and a tail rotor control device 182. The bulkhead 104 is provided, for example, between a bulkhead between the tail rotor system 40 and a main body portion (not shown) and the inside bottom of the electric rotorcraft body 20, and serves to support the electric motor system 100. In addition, for example, the area around the bulkhead 104 is an area where a part corresponding to an internal combustion engine in a conventional aircraft using an internal combustion engine was provided.

[0015] As shown in FIGS. 1 and 2, the main rotor 160 is connected to the main rotor shaft 154 and is rotatable about the rotation axis of the main rotor shaft 154.

[0016] The main rotor control device 172 is electrically connected to the flight control device 130, the main rotor 160, and the rotor blades 170. The main rotor control device 172 controls the rotor pitch of the rotor blades 170. For example, the main rotor control device 172 may change the rotor pitch of the rotor blades 170 according to the rotation speed of the main rotor 160, may change the rotor pitch of the rotor blades 170 according to each flight speed of the electric rotorcraft 10, or may change the angle of attack of the rotor blades 170 according to both the flight speed of the electric rotorcraft 10 and the rotation speed of the main rotor 160. The main rotor control device 172 may receive the rotor pitch corresponding to each flight speed of the electric rotorcraft 10 from the flight control device 130, and adjust the rotor pitch of the rotor blades 170 to the rotor pitch corresponding to each flight speed. Also, a rotor pitch corresponding to both the flight speed of the electric rotorcraft 10 and the rotation speed of the main rotor 160 may be received, and the rotor pitch of the multiple rotor blades 170 may be adjusted to a rotor pitch corresponding to each flight speed and rotation speed. Furthermore, a rotor pitch corresponding to the rotation speed of the main rotor 160 may be received, and the rotor pitch of the multiple rotor blades 170 may be adjusted to a rotor pitch corresponding to the rotation speed. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can maintain the rotor pitch of the multiple rotor blades 170 at a rotor pitch corresponding to each flight speed, and therefore can continue stable flight.

[0017] The main rotor control device 172 may have a storage device that stores the rotor pitch according to each flight speed, the rotor pitch according to the rotation speed, and the rotor pitch according to each flight speed and rotation speed received from the flight control device 130. Although details will be described later, in this specification, the rotation speed of the main rotor 160 is the same as the rotation speed of the main rotor shaft 154 and the rotation speed of the multiple rotor blades 170 provided on the main rotor 160, and may be called a desired rotation speed, a first rotation speed, a second rotation speed, a third rotation speed, or a fourth rotation speed. In this specification, the rotor pitch according to each flight speed, the rotor pitch according to the rotation speed, or the rotor pitch according to each flight speed and rotation speed received from the flight control device 130 may be called a desired rotor pitch, a first rotor pitch, a second rotor pitch, a third rotor pitch, or a fourth rotor pitch.

[0018] As shown in FIGS. 1 and 2, tail rotor 180 is connected to tail rotor shaft 156 and is rotatable about the axis of rotation of tail rotor shaft 156.

[0019] The tail rotor control device 182 is electrically connected to the flight control device 130 and the tail rotor 180. The tail rotor control device 182 controls, for example, the rotation speed of the tail rotor 180. The tail rotor control device 182 changes, for example, the rotation speed of the tail rotor 180 according to each flight speed of the electric rotorcraft 10. The tail rotor control device 182 receives, for example, from the flight control device 130, the rotation speed of the tail rotor 180 corresponding to each flight speed of the electric rotorcraft 10, and adjusts the rotation speed of the tail rotor 180 to the rotation speed of the tail rotor 180 corresponding to each flight speed. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can adjust the rotation speed of the tail rotor 180 to the rotation speed of the tail rotor 180 corresponding to each flight speed, and therefore can suppress the torque (reaction torque) generated by the rotation of the main rotor 160 causing the multiple rotor blades 170 to rotate according to each flight speed, and can continue stable flight. The tail rotor control device 182 may include a storage device that stores the number of rotations of the tail rotor 180 corresponding to each flight speed received from the flight control device 130.

[0020] As shown in FIG. 2, a first end of the drive shaft 152 is connected to the reducer 150 (FIG. 2) or the one-way clutch 105 (FIG. 2), and a second end of the drive shaft 152 is connected to the electric motor system 100. In FIG. 1 and FIG. 2, as an example, a first motor 100A and a second motor 100B included in the electric motor system 100 are connected to the drive shaft 152. That is, the first motor 100A and the second motor 100B are connected coaxially. The first motor 100A rotates the drive shaft 152 about the center of the rotation axis of the drive shaft 152, transmits power to the main rotor shaft 154 and the tail rotor shaft 156, and drives the main rotor system 30 and the tail rotor 180. The second motor 100B is provided in series with the first motor 100A with respect to the drive shaft 152, and like the first motor 100A, rotates the drive shaft 152 about the center of the rotation axis of the drive shaft 152 to transmit power to the main rotor shaft 154 and the tail rotor shaft 156, thereby driving the main rotor system 30 and the tail rotor 180. Note that the first motor 100A and the second motor 100B may be connected to different power shafts.

[0021] The first motor 100A and the second motor 100B have, for example, slip rings and are connected to the drive shaft 152 using the slip rings. As a result, the individual driving of the first motor 100A and the second motor 100B can be individually controlled. Also, the first motor 100A and the second motor 100B have, for example, slip rings and are connected to the drive shaft 152 using the slip rings.

[0022] A first end of the drive shaft 152, the main rotor shaft 154, and the tail rotor shaft 156 are connected to the reduction gear 150. The drive shaft 152 is rotatable about its rotation axis by the power generated by the electric motor system 100.

[0023] Here, for example, if the ground is a plane (D1D2 plane) or an approximate plane (approximately D1D2 plane) defined by the first axis (D1) and the second axis (D2), the third axis (D3) intersects with the plane or the approximate plane and is provided perpendicular or approximately perpendicular to the plane or the approximate plane. In a side view of the electric rotorcraft 10, the drive shaft 152 is provided parallel or approximately parallel to the third axis. In addition, in a side view of the electric rotorcraft 10, the angle formed by a line extending the drive shaft 152 to the third axis and a line extending the main rotor shaft 154 is an acute angle less than 90 degrees.

[0024] As the drive shaft 152 rotates, the power generated by the electric motor system 100 can be transmitted to the main rotor shaft 154 and the tail rotor shaft 156. That is, the power generated by the electric motor system 100 can be transmitted from one drive shaft 152 to a plurality of rotor shafts (here, the main rotor shaft 154 and the tail rotor shaft 156). As a result, the main rotor shaft 154 rotates about its rotation axis, and the main rotor 160 and the plurality of rotor blades 170 connected to the main rotor shaft 154 rotate, so that lift for lifting the electric rotorcraft 10 can be generated. In addition, the tail rotor shaft 156 rotates about its rotation axis, and the tail rotor 180 connected to the tail rotor shaft 156 rotates, so that the counter torque of the electric rotorcraft 10 can be suppressed. In addition, the tail rotor 180 can suppress torque (counter torque) that is generated when the plurality of rotor blades 170 rotate due to the rotation of the main rotor 160, for example.

[0025] The reduction gear 150 has a plurality of gears (not shown). The size, number of teeth, etc. of the plurality of gears may be different for some of the gears, or may be the same for some of the gears. The plurality of gears are provided at least between the drive shaft 152 and the main rotor shaft 154, and between the drive shaft 152 and the tail rotor shaft 156. Here, the rotation speed of the drive shaft 152 is extremely higher than the rotation speed of the main rotor shaft 154, the rotation speed of the main rotor 160 and the plurality of rotor blades 170 provided on the main rotor 160, the rotation speed of the tail rotor shaft 156, and the rotation speed of the tail rotor 180. The reduction gear 150 has gears with different sizes, numbers of teeth, etc., so that the rotation speed of the main rotor shaft 154 and the rotation speed of the tail rotor shaft 156 can be changed to a rotation speed lower than the rotation speed of the drive shaft 152. As a result, the reduction gear 150 can reduce the rotation speed of each rotor.

[0026] The main rotor shaft 154 is connected to the main rotor 160, and the tail rotor shaft 156 is electrically connected to the tail rotor 180. Therefore, the rotation speed of the main rotor shaft 154 is the same as the rotation speed of the main rotor 160 and the rotation speed of the multiple rotor blades 170 provided on the main rotor 160, and the rotation speed of the tail rotor shaft 156 is the same as the rotation speed of the tail rotor 180.

[0027] In the electric rotorcraft 20 according to one embodiment of the present invention, a one-way clutch 105 may be provided between the reduction gear 150 and the electric motor system 100. For example, when the first motor 100A and the second motor 100B fail, the one-way clutch 105 suppresses rotation of the drive shaft 152 and suppresses transmission of power to the main rotor 160 and the tail rotor 180. Therefore, when the first motor 100A and the second motor 100B fail, the drive shaft 152 is capable of free rotation, and the electric rotorcraft 10 according to one embodiment of the present invention has a configuration capable of autorotation.

[0028] The first motor control device 102A is electrically connected to the first motor 100A and the first battery management system 110A, and controls the driving of the first motor 100A. The first motor control device 102A includes, for example, an inverter (not shown), a rotation speed detection device (not shown), a rotation speed comparison device (not shown), and a rotation speed feedback device (not shown).

[0029] The inverter includes, for example, an inverter circuit and a capacitor provided in the inverter circuit. For example, the inverter stores power (DC) supplied from the first battery 120A in a capacitor and converts it into power (AC) in the inverter circuit. The inverter supplies the converted power (AC) to the first motor 100A.

[0030] The rotation speed detection device includes, for example, a first lookup table in which the flight speeds of the electric rotorcraft 10 are associated with the rotation speeds of the main rotor 160 corresponding to each flight speed, the rotation speeds of the tail rotor 180 corresponding to each flight speed, and the rotation speeds of the first motor 100A corresponding to each flight speed. The device also includes a second lookup table in which the rotation speeds of the main rotor 160 corresponding to each flight speed, the rotation speeds of the tail rotor 180 corresponding to each flight speed, and the rotation speeds of the first motor 100A corresponding to each flight speed are associated with current values. The first lookup table and the second lookup table may be, for example, different storage devices, or may be stored in the same storage device. The rotation speed detection device measures the value of the current flowing through the first motor 100A, and detects the rotation speed of the first motor 100A corresponding to each flight speed, the rotation speed of the main rotor 160 corresponding to each flight speed, and the rotation speed of the tail rotor 180 corresponding to each flight speed from the measured current value based on the first and second lookup tables. The rotation speed comparison device may include a storage device that stores the set rotation speed of the main rotor 160, the set rotation speed of the tail rotor 180, and the set rotation speed of the first motor 100A. The rotation speed comparison device receives the detected rotation speed of the first motor 100A from the rotation speed detection device, and can compare the detected rotation speed of the first motor 100A with the set rotation speed of the first motor 100A. As a result, when the detected rotation speed of the first motor 100A is the same as the set rotation speed of the first motor 100A, the rotation speed comparison device transmits the detected rotation speed of the first motor 100A to the rotation speed feedback device, and when the detected rotation speed of the first motor 100A is different from the set rotation speed of the first motor 100A, the rotation speed comparison device corrects the detected rotation speed of the first motor 100A to the set rotation speed of the first motor 100A and transmits it to the rotation speed feedback device. The rotation speed feedback device includes the first lookup table and the second lookup table, similar to the rotation speed detection device. The rotation speed feedback device receives the detected rotation speed of the first motor 100A or the set rotation speed of the first motor from the rotation speed comparison device.The rotation speed feedback device can determine the current value of the first motor 100A from the received rotation speed of the first motor 100A based on the first and second lookup tables. The rotation speed feedback device can maintain the rotation speed of the first motor 100A at a rotation speed corresponding to each flight speed by supplying the determined current value of the first motor 100A to the first motor 100A. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can maintain the rotation speed of the main rotor 160 and the rotation speed of the tail rotor 180 at a rotation speed corresponding to each flight speed, and can therefore continue stable flight.

[0031] The second motor control device 102B is electrically connected to the second motor 100B and the second battery management system 110B, and controls the driving of the second motor 100B. The second motor control device 102B has a configuration similar to that of the first motor control device 102A, and includes, for example, an inverter, a rotation speed detection device, a rotation speed comparison device, and a rotation speed feedback device. The inverter supplies the converted power (AC) to the second motor 100B. Therefore, the second motor control device 102B can maintain the rotation speed of the second motor 100B at a rotation speed corresponding to each flight speed by passing the obtained current value of the second motor 100B through the second motor 100B. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can maintain the rotation speed of the main rotor 160 and the rotation speed of the tail rotor 180 at a rotation speed corresponding to each flight speed, and therefore can continue stable flight. In this specification, the set rotation speed of the first motor and the set rotation speed of the second motor may be referred to as the desired rotation speed, the first rotation speed, the second rotation speed, the third rotation speed, or the fourth rotation speed.

[0032] The first motor control device 102A and the second motor control device 102B may be connected to each other. For example, the second motor control device 102B may share data such as the rotation speed and current value of the first motor 100A with the first motor control device 102A, and the first motor control device 102A may share data such as the rotation speed and current value of the second motor 100B with the second motor control device 102B.

[0033] An electric rotorcraft 10 according to one embodiment of the invention may be configured such that if the first motor control device 102A becomes uncontrollable, the second motor control device 102B is connected to the first motor 100A, and if the second motor control device 102B becomes uncontrollable, the first motor control device 102A is connected to the second motor 100B.

[0034] The flight control device 130 is connected to the main rotor control device 172, the tail rotor control device 182, the first motor control device 102A, and the second motor control device 102B. The flight control device 130 has a CPU, a storage device, and the like. For example, the flight control device 130 reads instructions stored in the storage device based on a signal input to the input device 142, processes the instructions using the CPU, and transmits desired signals and desired data to the main rotor control device 172, the tail rotor control device 182, the first motor control device 102A, and the second motor control device 102B.

[0035] The control device 140 is connected to the flight control device 130. The control device 140 includes an input device 142, a display device 144, and the like. The input device 142 includes, for example, a starter switch, a thrust control lever, and the like. The display device 144 is configured to display data in chronological order, such as, for example, the rotor pitch corresponding to each flight speed, the rotation speed and current value of the first motor 100A corresponding to each flight speed, the rotation speed and current value of the second motor 100B corresponding to each flight speed, the rotation speed of the main rotor 160 corresponding to each flight speed, and the rotation speed of the tail rotor 180 corresponding to each flight speed.

[0036] The pilot of the electric rotorcraft 10 inputs a desired operation using the flight control device 140. For example, the pilot inputs data of a desired rotor pitch corresponding to each flight speed into the input device 142. The input device 142 transmits the data of the desired rotor pitch to the flight control device 130. The flight control device 130 transmits the data of the desired rotor pitch to the main rotor control device 172. The data of the desired rotor pitch is stored (memorized) in the main rotor control device 172. For example, when adjusting the rotor pitch of the multiple rotor blades 170 according to the flight speed, the pilot inputs an operation for adjusting the rotor pitch of the multiple rotor blades 170 into the input device 142, and the input device 142 transmits a first control signal corresponding to the operation for adjusting the rotor pitch of the multiple rotor blades 170 to the flight control device 130. The flight control device 130 receives the first control signal and transmits a second control signal to the main rotor control device 172 based on the first control signal to adjust the rotor pitch of the rotor blades 170 to maintain the desired rotor pitch. The main rotor control device 172 receives the second control signal and adjusts the rotor pitch of the rotor blades 170 to maintain the desired rotor pitch based on the second control signal. The first control signal may include a signal corresponding to an operation for adjusting the rotation speed of each power shaft, each output shaft, main rotor 160, or tail rotor 180 to the desired rotation speed of each power shaft, each output shaft, main rotor 160, or tail rotor 180. The second control signal may also include a signal for adjusting the rotation speed of each power shaft, each output shaft, main rotor 160, or tail rotor 180 to maintain the desired rotation speed of each power shaft, each output shaft, main rotor 160, or tail rotor 180.

[0037] As described above, the power control system 110 includes the first battery management system 110A, the second battery management system 110B, the first battery 120A, the second battery 120B, and the third battery 120C. The first battery management system 110A is connected to the flight control device 130, the first motor control device 102A, and the first battery 120A. The first battery management system 110A controls the remaining capacity of the first battery 120A, and supplies power from the first battery 120A to the first motor control device 102A. The second battery management system 110B is connected to the flight control device 130, the second motor control device 102B, and the second battery 120B. The second battery management system 110B, like the first battery management system 110A, controls the remaining charge of the second battery 120B and supplies power from the second battery 120B to the second motor control device 102B. The third battery 120C is connected to the flight control device 130 and the piloting device 140 and supplies power to the flight control device 130 and the piloting device 140. The flight control device 130 also has a role of controlling the remaining charge of the third battery 120C and the supply of power to the flight control device 130 and the piloting device 140. The power control system 110 may have a third battery management system that is connected to the flight control device 130 and the third battery 120C and controls the remaining charge of the third battery 120C and the supply of power to the flight control device 130 and the piloting device 140.

[0038] The first battery management system 110A and the second battery management system 110B may be connected to each other. For example, the second battery management system 110B may share data such as the remaining capacity of the first battery 120A with the first battery management system 110A, and the first battery management system 110A may share data such as the remaining capacity of the second battery 120B with the second battery management system 110B. For example, even if the first battery management system 110A becomes uncontrollable, the second battery management system 110B can control the first battery 120A, and even if the second battery management system 110B becomes uncontrollable, the first battery management system 110A can control the second battery 120B. Therefore, the electric rotorcraft 10 according to one embodiment of the present invention can supply the electric power required for flight to the motor control device, ensure power, and ensure safety even if the battery management system fails.

[0039] As described above, the flight control device 130 is electrically connected to the main rotor control device 172, the tail rotor control device 182, the first motor control device 102A, and the second motor control device 102B. In addition, the flight control device 130 transmits data of a desired rotor pitch corresponding to each flight speed of the electric rotorcraft 10 to the main rotor control device 172, transmits data of the tail rotor rotation speed corresponding to each flight speed of the electric rotorcraft 10 to the tail rotor control device 182, and transmits data of a desired rotation speed corresponding to each flight speed of the electric rotorcraft 10 to the first motor control device 102A and the second motor control device 102B. The main rotor control device 172 adjusts the rotor pitch of the rotor blades 170 to maintain a desired rotor pitch according to each flight speed of the electric rotorcraft 10, the tail rotor control device 122 adjusts the rotation speed of the tail rotor 180 to maintain a rotation speed according to each flight speed of the electric rotorcraft 10, the first motor control device 102A detects the rotation speed of the first motor 100A and adjusts the rotation speed of the first motor 100A to a desired rotation speed, and the second motor control device 102B adjusts the rotation speed of the second motor 100B to a desired rotation speed. By the above-mentioned operations, the electric rotorcraft 10 according to one embodiment of the present invention can be provided with a transmission mechanism that can control both the rotation speed and the rotor pitch according to the flight speed, compared to a conventional aircraft using an internal combustion engine.

[0040] 3, a motor for driving the main rotor 160 and a motor for driving the tail rotor 180 may be provided separately. For example, in the electric rotorcraft 10, the first motor 100A and the second motor 100B are motors for driving the main rotor 160, and the third motor 200A is a motor for driving the tail rotor 180. The configuration of the electric rotorcraft 10 shown in FIG. 3 is different from the configuration of the electric rotorcraft 10 shown in FIG. 2 in that it does not include the tail rotor shaft 156 and includes an electric motor system 200 including a third motor 200A and a third motor control device 202A. Descriptions of configurations that are the same as or similar to those in FIGS. 1 and 2 will be omitted.

[0041] The third motor control device 202A is electrically connected to the electric motor system 100, the power control system 110, the main rotor control device 172, the tail rotor control device 182, and the third motor 200A, and controls the driving of the third motor 200A. The third motor 200A is connected to the tail rotor 180, and the tail rotor 180 is configured as a direct drive type motor. The third motor control device 202A has a similar configuration to that of the first motor control device 102A, for example. The third motor control device 202A can control the rotation speed of the third motor 200A, the rotation speed of the tail rotor 180, and the rotor pitch of the tail rotor 180 according to each flight speed, and drive the third motor 200A and the tail rotor 180.

[0042] 3, the electric rotorcraft 10 according to one embodiment of the present invention can independently control the main rotor 160 and the tail rotor 180. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can be controlled more efficiently because it is possible to change, for example, the speed ratio between the main rotor 160 and the tail rotor 180.

[0043] As described above, a conventional rotorcraft using an internal combustion engine generates power by the internal combustion engine and transmits the generated power to the rotor shaft. When the internal combustion engine is used as the power source, for example, a power drop due to incomplete combustion of fuel in the internal combustion engine and an unstable power supply in the flight environment may occur. As a result, it has been difficult to finely control both the rotor rotation speed and the rotor pitch according to each flight speed. On the other hand, the electric rotorcraft 10 according to one embodiment of the present invention can replace the part corresponding to the internal combustion engine with a transmission mechanism compared to a conventional aircraft using an internal combustion engine, and generates power by an electric motor that can be electrically controlled, so that the power is not influenced by the performance of the internal combustion engine. Therefore, the electric rotorcraft 10 can stably supply power to be transmitted to the rotor shaft compared to a conventional rotorcraft using an internal combustion engine. As a result, the electric rotorcraft 10 according to one embodiment of the present invention can stably control both the rotor rotation speed and the rotor pitch according to each flight speed, or can finely control both the rotor rotation speed and the rotor pitch according to each flight speed.

[0044] Although an electric rotorcraft 10 according to an embodiment of the present invention has two electric motors, the number of electric motors is not limited to two. For example, the electric rotorcraft 10 may have three or more electric motors. As a result, even if at least two electric motors fail, the electric rotorcraft 10 can ensure the power required for flight and ensure safety. Furthermore, by having more electric motors, the electric rotorcraft 10 can stably transmit power to the main rotor 160 or the tail rotor 180 regardless of flight altitude, weather, temperature, and the like. As a result, the electric rotorcraft 10 can further stabilize both the rotor rotation speed and rotor pitch according to each flight speed. <1-2. Flight modes of electric rotorcraft 10>

[0045] The flight modes of the electric rotorcraft 10 according to one embodiment of the present invention will be described with reference to Fig. 4. Fig. 4 is a state transition diagram showing the flight modes of the electric rotorcraft 10 according to one embodiment of the present invention. The flight modes of the electric rotorcraft 10 shown in Fig. 4 are only an example, and the flight modes of the electric rotorcraft 10 are not limited to the states shown in Fig. 4. Descriptions of configurations that are the same as or similar to those in Figs. 1 and 2 may be omitted.

[0046] As will be described in more detail later, the flight control device 130 flies the electric rotorcraft 10 in at least a standby mode in which the electric rotorcraft 10 is in a standby state, and a first flight state in which, depending on the flight speed of the electric rotorcraft 10 when ascent or descent, the rotation speed of the main rotor shaft 154 is adjusted to a first rotation speed corresponding to the flight speed of the electric rotorcraft 10 when ascent or descent, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a first rotor pitch corresponding to the flight speed of the electric rotorcraft 10 when ascent or descent. a normal mode in which the electric rotorcraft 10 is rotated at a constant speed so as to rotate at a constant speed, and a second flight state in which the rotation speed of the main rotor shaft 154 corresponding to the flight speed of the electric rotorcraft 10 is adjusted to a second rotation speed so as to minimize the power to drive the electric rotorcraft 10 corresponding to the flight speed of the electric rotorcraft 10, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a second rotor pitch so as to minimize the power to drive the electric rotorcraft 10 corresponding to the flight speed of the electric rotorcraft 10. and a third flight state in which the rotation speed of the main rotor shaft 154 is adjusted to a third rotation speed corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum surplus power so that the flight speed of the electric rotorcraft 10 becomes a flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum surplus power, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a third rotor pitch corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum surplus power. a power mode in which the electric rotorcraft 10 is operated in a power mode, and the rotation speed of the main rotor shaft 154 corresponding to the flight speed is adjusted to a fourth rotation speed that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 so as to suppress noise generated by the rotation of the main rotor 160 and the rotor blades 170, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a fourth rotor pitch that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170,and a silent mode in which the electric rotorcraft 10 flies in a fourth flight state that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 provided on the main rotor 160. The flight control device 130 can also switch modes and select each mode based on an instruction for transition between each state.

[0047] The standby state of the electric rotorcraft 10 is a state in which the electric rotorcraft 10 is stopped on the ground, for example, a state in which the electric motor system 100 is not operating, or a state in which the electric motor system 100 is operating and the electric rotorcraft 10 is stopped on the ground. <1-2-1. Start process>

[0048] As shown in FIG. 4, the electric rotorcraft 10 transitions from the standby state to the first state by the start process. In this specification and the like, the first state is called the first flight state, and the normal mode is a mode in which the electric rotorcraft 10 flies in the first flight state, and is called the first mode. Note that the start process of the electric rotorcraft 10 according to an embodiment of the present application described here is merely an example of a process for transitioning the electric rotorcraft 10 from the standby state to the ascent state and the flight state. There is no limitation on the processing method of the start process of the electric rotorcraft 10 according to an embodiment of the present application, as long as it is a process that can fly the electric rotorcraft 10 in a first flight state in which the rotation speed of the main rotor shaft 154 corresponding to the flight speed during ascent is adjusted to a first rotation speed corresponding to the flight speed during ascent or descent of the electric rotorcraft 10, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a first rotor pitch corresponding to the flight speed during ascent or descent of the electric rotorcraft 10.

[0049] First, the pilot of the electric rotorcraft 10 uses the control device 140 to, for example, turn on the starter switch (step S10). When the starter switch is turned on (ON), the input device 142 transmits a signal (motor drive signal) for driving the electric motor system 100 to the flight control device 130 (step S12). Upon receiving the motor drive signal, the flight control device 130 transmits the motor drive signal to the electric motor system 100 and the power control system 110 (step S14).

[0050] When the power control system 110 receives the motor drive signal, it supplies power to the electric motor system 100 (step S16). When the electric motor system 100 receives the motor drive signal and is supplied with power, it drives the first motor 100A and the second motor 100B. As a result, the first motor 100A and the second motor 100B start to rotate and supply power to the main rotor 160 and the tail rotor 180 via multiple rotating shafts (step S18). When power is supplied to the main rotor 160, it rotates about the axial center of the main rotor shaft 154, and when power is supplied to the tail rotor 180, it starts to rotate (step S20).

[0051] When the main rotor 160 and the tail rotor 180 start to rotate, for example, the main rotor control device 172 and the tail rotor control device 182 send a signal indicating that rotation has started to the flight control device 130. When the flight control device 130 receives the signal indicating that rotation has started, it can send the signal indicating that rotation has started to the input device 142, thereby notifying the pilot that the main rotor 160 and the tail rotor 180 have started to rotate.

[0052] Next, when the pilot is notified by the flight control device 130 to start rotation, he or she instructs the electric rotorcraft 10 to ascend using the flight control device 140, and inputs data on a first rotation speed of the main rotor shaft 154 that corresponds to the flight speed of the ascent, and data on a first rotor pitch of the multiple rotor blades 170 that corresponds to the flight speed of the ascent, into the input device 142 (step S22). At this time, the pilot may also input data on the rotation speed of the tail rotor 180 and other data necessary for flying the electric rotorcraft 10 into the input device 142.

[0053] Based on the command to ascend the electric rotorcraft 10, the input device 142 transmits to the flight control device 130 a signal instructing the electric rotorcraft 10 to ascend (ascent control signal) and a first control signal corresponding to an operation for adjusting the rotor pitch of the multiple rotor blades 170 and the rotation speeds of the main rotor 160 and the tail rotor 180 (step S24). Here, for example, the first control signal includes data on a first rotation speed corresponding to the flight speed of the ascent, data on a first rotor pitch corresponding to the flight speed of the ascent, data on the rotation speed of the tail rotor 180, and other data necessary for the flight of the electric rotorcraft 10.

[0054] When the flight control device 130 receives the ascent control signal and the first control signal, it transmits to the electric motor system 100, the tail rotor control device 182, and the main rotor control device 172 a second control signal for adjusting the rotational speed of the main rotor shaft 154 to be kept at a first rotational speed corresponding to the flight speed of ascent and for adjusting the rotor pitch of the rotor blades 170 to be kept at a first rotor pitch corresponding to the flight speed of ascent (step S26). When the electric motor system 100 receives the ascent control signal and the second control signal, it controls the first motor 100A and the second motor 100B to adjust the rotational speed of the main rotor shaft 154 to be kept at a first rotational speed corresponding to the flight speed of ascent (step S28). When the main rotor control device 172 receives the ascent control signal and the second control signal, it adjusts the rotor pitch of the rotor blades 170 to be kept at a first rotor pitch corresponding to the flight speed of ascent. When the tail rotor control device 182 receives the ascent control signal and the second control signal, it adjusts the rotation speed of the tail rotor 180 so as to maintain it at a desired rotation speed according to the ascent flight speed (step S30).

[0055] As described above, the start process transitions the electric rotorcraft 10 from the standby state to the first state. Note that the electric rotorcraft 10 may successively change the flight speed during ascent depending on environmental conditions such as altitude and temperature, and adjust the rotation speed of the main rotor shaft 154, the first rotor pitch, and the rotation speed of the tail rotor 180. <1-2-2. Landing Processing>

[0056] As shown in FIG. 4, the landing process causes the electric rotorcraft 10 to transition from the first state to a descending state and then to a standby state. In this specification and the like, a mode in which the electric rotorcraft 10 flies in a descending state is called a coasting mode. The coasting mode is, for example, a mode in which the electric rotorcraft 10 flies by inertia without powered acceleration or deceleration, for example, a mode in which the electric rotorcraft 10 flies in a state close to autorotation. The coasting mode is also called, for example, coasting or coasting. Explanation of steps that are the same as or similar to the start process may be omitted. Note that the landing process of the electric rotorcraft 10 according to an embodiment of the present application described here is merely an example of a process in which the electric rotorcraft 10 transitions from the first state to a descending state and then to a standby state. There are no limitations on the method of the landing process of the electric rotorcraft 10 according to an embodiment of the present application as long as the landing process can fly the electric rotorcraft in a state close to autorotation. In addition, the landing processing of the electric rotorcraft 10 according to one embodiment of the present application may be a processing capable of flying the electric rotorcraft in a descending state by adjusting the rotation speed of the main rotor shaft 154 corresponding to the flight speed during descent to a first rotation speed corresponding to the flight speed during descent, and adjusting the rotor pitch of the rotor blades 170 corresponding to the flight speed to a first rotor pitch corresponding to the flight speed during descent.

[0057] First, the pilot of the electric rotorcraft 10, for example, uses the flight control device 140 to instruct the electric rotorcraft 10 to change from a first state to a standby state and to instruct the electric rotorcraft 10 to descend, putting the drive shaft 152 into a state capable of free rotation, and putting the electric rotorcraft 10 according to one embodiment of the present invention into a state capable of autorotation (step S32). At this time, the pilot may input data of a first rotation speed of the main rotor shaft 154 corresponding to the flight speed of descent and data of a first rotor pitch of the plurality of rotor blades 170 corresponding to the flight speed of ascent into the input device 142, and the pilot may also input data of the rotation speed of the tail rotor 180 and other data necessary for flying the electric rotorcraft 10 into the input device 142.

[0058] Based on the descent command for the electric rotorcraft 10, the input device 142 transmits to the flight control device 130 a signal instructing the electric rotorcraft 10 to descend (descent control signal), a first control signal corresponding to an operation for putting the electric rotorcraft 10 into a state capable of autorotation, or a first control signal corresponding to an operation for adjusting the rotor pitch of the multiple rotor blades 170 and the rotation speeds of the main rotor 160 and the tail rotor 180 (step S54). Here, for example, the first control signal includes data on a first rotation speed corresponding to the flight speed of descent, data on a first rotor pitch corresponding to the flight speed of descent, data on the rotation speed of the tail rotor 180, and other data necessary for the flight of the electric rotorcraft 10.

[0059] Upon receiving the descent control signal and the first control signal, the flight control device 130 transmits to the electric motor system 100, the tail rotor control device 182, and the main rotor control device 172 a second control signal for putting the drive shaft 152 in a state capable of free rotation, or a second control signal for adjusting the rotation speed of the main rotor shaft 154 to be kept at a first rotation speed corresponding to the flight speed of descent and adjusting the rotor pitch of the rotor blades 170 to be kept at a first rotor pitch corresponding to the flight speed of descent (step S56). Upon receiving the descent control signal and the second control signal, the electric motor system 100 controls the first motor 100A and the second motor 100B to adjust the rotation speed of the main rotor shaft 154 to be kept at a first rotation speed corresponding to the flight speed of descent (step S58). Upon receiving the descent control signal and the second control signal, the main rotor control device 172 adjusts the rotor pitch of the rotor blades 170 to be kept at a first rotor pitch corresponding to the flight speed of descent. When the tail rotor control device 182 receives the descent control signal and the second control signal, it adjusts the rotation speed of the tail rotor 180 so as to maintain it at a desired rotation speed according to the flight speed during descent (step S60).

[0060] Next, once the main rotor 160 and the tail rotor 180 have been adjusted to maintain a desired rotation speed according to the flight speed of descent, for example, the main rotor control device 172 and the tail rotor control device 182 send a signal indicating the start of descent to the flight control device 130 (step S62). Upon receiving the signal indicating the start of descent, the flight control device 130 sends a signal indicating the start of descent to the input device 142, and is able to notify the pilot that the descent of the electric rotorcraft 10 has started (step S64). Note that the electric rotorcraft 10 may successively change the flight speed of descent depending on environmental conditions such as altitude and temperature, and adjust the rotation speed of the main rotor shaft 154, the first rotor pitch, and the rotation speed of the tail rotor 180.

[0061] Next, when the electric rotorcraft 10 lands, for example, the electric rotorcraft 10 detects that it has landed. The electric rotorcraft 10 is equipped with a detector such as an acceleration sensor or a gyro sensor, and is able to detect that it has landed. When the detector detects the landing of the electric rotorcraft 10, it transmits a signal corresponding to the landing (landing signal) to the flight control device 130. When the flight control device 130 receives the landing signal, it transmits the landing signal to the input device 142, and is able to notify the pilot that the electric rotorcraft 10 has landed.

[0062] When the pilot is notified of the landing, he or she turns the starter switch to the OFF state, for example (step S66). Based on the starter switch being turned to the OFF state, the input device 142 transmits a signal to stop the electric motor system 100 (motor stop signal) to the flight control device 130 (step S68). When the flight control device 130 receives the motor stop signal, it transmits the motor stop signal to the electric motor system 100 and the power control system 110 (step S70).

[0063] When the power control system 110 receives the motor stop signal, it stops the supply of power to the electric motor system 100, for example (step S72). When the electric motor system 100 receives the motor stop signal and the supply of power is stopped, it stops the first motor 100A and the second motor 100B. As a result, the first motor 100A and the second motor 100B stop rotating, and the supply of power to the multiple rotating shafts is stopped (step S74). As a result, the power is stopped from the main rotor 160 and the tail rotor 180, and they stop rotating (step S76).

[0064] As described above, the landing process causes the electric rotorcraft 10 to transition from the first state to the descending state, and then to the waiting state. <1-2-3. First process>

[0065] As shown in FIG. 4, the first process transitions the electric rotorcraft 10 from a first state to a second state. In this specification and the like, the second state is referred to as a second flight state, and the eco mode is a mode in which the electric rotorcraft 10 flies in the second flight state and is referred to as the second mode. Descriptions of steps that are the same as or similar to the start process and standby process may be omitted. Note that the first process of the electric rotorcraft 10 according to an embodiment of the present application described here is merely an example of a process for transitioning the electric rotorcraft 10 from the first state to the second state. The first processing of the electric rotorcraft 10 according to one embodiment of the present application is not limited to a processing method as long as it is processing that can fly the electric rotorcraft in a second flight state in which the rotation speed of the main rotor shaft 154 corresponding to the flight speed of the electric rotorcraft 10 is adjusted to a second rotation speed such that the power driving the electric rotorcraft 10 corresponding to the flight speed of the electric rotorcraft 10 is minimized depending on the flight speed of the electric rotorcraft 10, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a second rotor pitch such that the power driving the electric rotorcraft 10 corresponding to the flight speed of the electric rotorcraft 10 is minimized.

[0066] First, the pilot of the electric rotorcraft 10 uses, for example, the flight control device 140 to instruct the electric rotorcraft 10 to transition from the first state to the second state, and inputs, into the input device 142, data on the second rotation speed of the main rotor shaft 154 corresponding to the flight speed at which the electric power driving the electric rotorcraft 10 is minimized, and data on the second rotor pitch of the multiple rotor blades 170 corresponding to the flight speed at which the electric power driving the electric rotorcraft 10 is minimized (step S82). At this time, the pilot may also input data on the rotation speed of the tail rotor 180 and other data necessary for the flight of the electric rotorcraft 10 into the input device 142. In the following description, the flight speed at which the electric power driving the electric rotorcraft 10 is minimized will be referred to as the minimum power flight speed.

[0067] Based on the instruction to transition the electric rotorcraft 10 to the second state, the input device 142 transmits to the flight control device 130 a signal (second state control signal) instructing the transition of the electric rotorcraft 10 to the second state, and a first control signal corresponding to an operation for adjusting the first rotor pitch of the multiple rotor blades 170 and the first rotation speeds of the main rotor 160 and the tail rotor 180 (step S84). Here, for example, the first control signal includes data of the second rotation speed according to the minimum power flight speed, data of the second rotor pitch according to the minimum power flight speed, data of the rotation speed of the tail rotor 180, and other data necessary for flight of the electric rotorcraft 10.

[0068] When the flight control device 130 receives the second state control signal and the first control signal, the flight control device 130 transmits a second control signal to the electric motor system 100, the tail rotor control device 182, and the main rotor control device 172 to adjust the first rotation speed of the main rotor shaft 154 to be kept at the second rotation speed corresponding to the power minimum flight speed and to adjust the first rotor pitch of the rotor blades 170 to be kept at the second rotor pitch corresponding to the power minimum flight speed (step S86). When the electric motor system 100 receives the second state control signal and the second control signal, the electric motor system 100 controls the first motor 100A and the second motor 100B to adjust the first rotation speed of the main rotor shaft 154 to be kept at the second rotation speed corresponding to the power minimum flight speed (step S88). When the main rotor control device 172 receives the second state control signal and the second control signal, the main rotor control device 172 adjusts the first rotor pitch of the rotor blades 170 to be kept at the second rotor pitch corresponding to the power minimum flight speed. When the tail rotor control device 182 receives the second state control signal and the second control signal, it adjusts the rotation speed of the tail rotor 180 so as to maintain the rotation speed at a desired rotation speed corresponding to the power minimum flight speed (step S90).

[0069] As described above, the electric rotorcraft 10 transitions from the first state to the second state by the first process. The electric rotorcraft 10 may successively change the minimum electric flight speed and adjust the second rotation speed, the second rotor pitch, and the rotation speed of the tail rotor 180 depending on the environmental conditions such as the altitude and the temperature. In this specification and the like, the process in which the electric rotorcraft 10 transitions from the second state to the first state is also referred to as the first process. The first process in which the electric rotorcraft 10 transitions from the second state to the first state can be performed in the same manner as the process in which the electric rotorcraft 10 transitions from the first state to the second state by replacing the first state with the second state, the second state with the first state, the first rotation speed with the second rotation speed, and the second rotation speed with the first rotation speed, in each step of the process in which the electric rotorcraft 10 transitions from the first state to the second state. <1-2-4. Second Processing>

[0070] As shown in FIG. 4, the second process transitions the electric rotorcraft 10 from the second state to a third state. In this specification and the like, the third state is referred to as a third flight state, and the power mode is a mode in which the electric rotorcraft 10 flies in the third flight state and is referred to as the third mode. Descriptions of steps that are the same as or similar to the start process, standby process, and first process may be omitted. Note that the second process of the electric rotorcraft 10 according to an embodiment of the present application described here is merely an example of a process for transitioning the electric rotorcraft 10 from the second state to the third state. The second processing of the electric rotorcraft 10 according to one embodiment of the present application is a processing method that is not limited as long as it is a processing that can fly the electric rotorcraft in a third flight state in which the rotation speed of the main rotor shaft 154 corresponding to the flight speed is adjusted to a third rotation speed corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum excess power, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a third rotor pitch corresponding to the flight speed at which the electric rotorcraft is flown with a predetermined maximum excess power, so that the flight speed of the electric rotorcraft becomes the flight speed at which it is flown with a predetermined maximum excess power.

[0071] First, the pilot of the electric rotorcraft 10, for example, uses the control device 140 to instruct the electric rotorcraft 10 to transition from the second state to the third state, and inputs, into the input device 142, data on a third rotation speed of the main rotor shaft 154 corresponding to a flight speed at a predetermined maximum excess power so that the flight speed of the electric rotorcraft becomes a flight speed at a predetermined maximum excess power, and data on a third rotor pitch of the rotor blades 170 corresponding to a flight speed at a predetermined maximum excess power so that the flight speed of the electric rotorcraft becomes a flight speed at a predetermined maximum excess power (step S92). At this time, the pilot may also input data on the rotation speed of the tail rotor 180 and other data necessary for flight of the electric rotorcraft 10 into the input device 142.

[0072] Based on the instruction to transition the electric rotorcraft 10 to the third state, the input device 142 transmits to the flight control device 130 a signal (third state control signal) instructing the transition of the electric rotorcraft 10 to the third state, and a first control signal corresponding to an operation for adjusting the first rotor pitch of the multiple rotor blades 170 and the third rotation speed of the main rotor 160 and the tail rotor 180 (step S94). Here, for example, the first control signal includes data of the third rotation speed corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum excess power, data of the third rotor pitch corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum excess power, data of the rotation speed of the tail rotor 180 corresponding to the flight speed at which the electric rotorcraft 10 is flown with a predetermined maximum excess power, and other data necessary for the flight of the electric rotorcraft 10.

[0073] When the flight control device 130 receives the third state control signal and the first control signal, the flight control device 130 adjusts the second rotation speed of the main rotor shaft 154 to be kept at a third rotation speed corresponding to the flight speed for flying the electric rotorcraft 10 with a predetermined maximum excess power, and transmits a second control signal to the electric motor system 100, the tail rotor control device 182, and the main rotor control device 172 for adjusting the second rotor pitch of the rotor blades 170 to be kept at a third rotor pitch corresponding to the flight speed for flying the electric rotorcraft 10 with a predetermined maximum excess power (step S96). When the electric motor system 100 receives the third state control signal and the second control signal, the electric motor system 100 controls the first motor 100A and the second motor 100B to adjust the second rotation speed of the main rotor shaft 154 to be kept at a third rotation speed corresponding to the flight speed for flying the electric rotorcraft 10 with a predetermined maximum excess power (step S98). When the main rotor control device 172 receives the third state control signal and the second control signal, it adjusts the first rotor pitch of the multiple rotor blades 170 to maintain the first rotor pitch at a third rotor pitch corresponding to the flight speed to fly the electric rotorcraft 10 with a predetermined maximum excess power. When the tail rotor control device 182 receives the third state control signal and the second control signal, it adjusts the rotation speed of the tail rotor 180 to maintain the desired rotation speed corresponding to the flight speed to fly the electric rotorcraft 10 with a predetermined maximum excess power (step S100).

[0074] As described above, the electric rotorcraft 10 transitions from the second state to the third state by the second process. The electric rotorcraft 10 according to an embodiment of the present application is provided with a power mode, and thus is capable of flying with a predetermined maximum surplus power. As a result, the electric rotorcraft 10 can fly using the surplus power, and is capable of agile flight. The electric rotorcraft 10 may adjust the third rotation speed, the third rotor pitch, and the rotation speed of the tail rotor 180 depending on environmental conditions such as altitude and temperature so that the electric rotorcraft 10 flies with a predetermined maximum surplus power. In this specification and the like, the process in which the electric rotorcraft 10 transitions from the third state to the second state is also referred to as the second process. The second processing when electric rotorcraft 10 transitions from the third state to the second state can be processed in the same manner as the processing when electric rotorcraft 10 transitions from the second state to the third state, by replacing the second state with the third state, the third state with the second state, the second rotation speed with the third rotation speed, and the third rotation speed with the second rotation speed, in each step of the processing when electric rotorcraft 10 transitions from the second state to the third state. <1-2-5. Third Processing>

[0075] As shown in FIG. 4, the third process causes the electric rotorcraft 10 to transition from the third state to a fourth state. In this specification and the like, the fourth state is referred to as a fourth flight state, and the silent mode is a mode in which the electric rotorcraft 10 flies in the fourth flight state and is referred to as a fourth mode. Descriptions of steps that are the same as or similar to the start process, standby process, first process, and second process may be omitted. Note that the third process of the electric rotorcraft 10 according to an embodiment of the present application described here is merely an example of a process for transitioning the electric rotorcraft 10 from the third state to the fourth state. The third processing of the electric rotorcraft 10 according to one embodiment of the present application is a processing method that is not limited as long as it is a processing that can fly the electric rotorcraft in a fourth flight state in which the rotation speed of the main rotor shaft 154 corresponding to the flight speed of the electric rotorcraft is adjusted to a fourth rotation speed that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 so as to suppress noise generated by the rotation of the main rotor 160 and the rotor blades 170, and the rotor pitch of the rotor blades 170 corresponding to the flight speed is adjusted to a fourth rotor pitch that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170.

[0076] First, the pilot of the electric rotorcraft 10, for example, uses the control device 140 to instruct the electric rotorcraft 10 to transition from the third state to the fourth state, and inputs data on the fourth rotation speed of the main rotor shaft 154 that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 according to the flight speed, and data on the fourth rotor pitch of the multiple rotor blades 170 that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 according to the flight speed, into the input device 142 (step S102). At this time, the pilot may also input data on the rotation speed of the tail rotor 180 and other data necessary for the flight of the electric rotorcraft 10 into the input device 142. In the following description, the flight speed that suppresses noise generated by the rotation of the main rotor 160 and the rotor blades 170 according to the flight speed is called a noise suppression flight speed.

[0077] Based on the instruction to transition the electric rotorcraft 10 to the fourth state, the input device 142 transmits to the flight control device 130 a signal (fourth state control signal) instructing the transition of the electric rotorcraft 10 to the fourth state, and a first control signal corresponding to an operation for adjusting the first rotor pitch of the multiple rotor blades 170 and the fourth rotation speeds of the main rotor 160 and the tail rotor 180 (step S104). Here, for example, the first control signal includes data of the fourth rotation speed according to the noise suppression flight speed, data of the fourth rotor pitch according to the noise suppression flight speed, data of the rotation speed of the tail rotor 180, and other data necessary for flight of the electric rotorcraft 10.

[0078] When the flight control device 130 receives the fourth state control signal and the first control signal, the flight control device 130 transmits a second control signal to the electric motor system 100, the tail rotor control device 182, and the main rotor control device 172 to adjust the third rotation speed of the main rotor shaft 154 to be kept at a fourth rotation speed corresponding to the noise suppression flight speed and to adjust the third rotor pitch of the rotor blades 170 to be kept at a fourth rotor pitch corresponding to the noise suppression flight speed (step S106). When the electric motor system 100 receives the fourth state control signal and the second control signal, the electric motor system 100 controls the first motor 100A and the second motor 100B to adjust the third rotation speed of the main rotor shaft 154 to be kept at a fourth rotation speed corresponding to the noise suppression flight speed (step S108). When the main rotor control device 172 receives the third state control signal and the second control signal, the main rotor control device 172 adjusts the first rotor pitch of the rotor blades 170 to be kept at a fourth rotor pitch corresponding to the noise suppression flight speed. When the tail rotor control device 182 receives the fourth state control signal and the second control signal, it adjusts the rotation speed of the tail rotor 180 so as to maintain it at a desired rotation speed according to the noise suppression flight speed (step S110).

[0079] As described above, the electric rotorcraft 10 transitions from the third state to the fourth state by the third process. The third process can suppress noise according to the flight speed. For example, a phenomenon in which a wingtip vortex released from a leading rotor blade 170 among a plurality of rotor blades 170 interferes with a trailing rotor blade 170, such as BVI noise (Blade Vortex Interaction Noise), may be detected using a detector such as an acceleration sensor or a microphone, and the rotation speed of the main rotor shaft 154 according to the flight speed may be adjusted to a fourth rotation speed at which the detected BVI noise is minimized, and the rotor pitch of the rotor blades 170 according to the flight speed may be adjusted to the fourth rotor pitch at which the detected BVI noise is minimized.

[0080] In the silent mode of the present embodiment, not only can noise be suppressed according to flight speed, but also, for example, both noise outside the aircraft and noise inside the aircraft can be suppressed. For example, in the electric rotorcraft 10, the detector can be provided on the outside of the aircraft (for example, on a skid (not shown)) to suppress noise outside the aircraft. Also, in the electric rotorcraft 10, the detector can be provided on the inside of the aircraft (for example, near the passenger heads in the cabin (not shown)) to suppress noise inside the aircraft. Noise increases and decreases depending on flight speed, for example, aerodynamic resonance, structural resonance, or resonance. The silent mode of the present embodiment is a mode that is effective for both noise outside the aircraft and noise inside the aircraft because it controls the rotor rotation speed and rotor pitch based on noise detected using a detector.

[0081] The electric rotorcraft 10 may sequentially change the noise suppression flight speed and adjust the fourth rotation speed, the fourth rotor pitch, and the rotation speed of the tail rotor 180 depending on environmental conditions such as altitude and temperature. In this specification and the like, the processing when the electric rotorcraft 10 transitions from the fourth state to the third state is also referred to as the third processing. The third processing when the electric rotorcraft 10 transitions from the fourth state to the third state can be performed in the same manner as the processing when the electric rotorcraft 10 transitions from the third state to the fourth state, by replacing the third state with the fourth state, the fourth state with the third state, the third rotation speed with the fourth rotation speed, and the fourth rotation speed with the third rotation speed, in each step of the processing when the electric rotorcraft 10 transitions from the third state to the fourth state.

[0082] In this specification, each piece of data input by the pilot to the input device 142 may be configured to be data that is pre-stored (stored) in the pilot device and can be selected according to each flight mode. For example, the display device 144 may have a touch panel function, and the pilot may select a flight mode displayed on the display device 144, and further select a flight speed, rotation speed, and rotor pitch according to the selected flight mode.

[0083] Conventionally, a pilot operates a control device 140 (e.g., a collecting lever, etc.) to finely adjust, for example, the rotor rotation speed and rotor pitch according to each flight speed. On the other hand, in the electric rotorcraft 10 according to one embodiment of the present invention, a plurality of modes such as a normal mode, an eco mode, a power mode, and a silent mode can be selected, and both the rotor rotation speed and rotor pitch can be stably controlled according to each mode based on each process, or both the rotor rotation speed and rotor pitch can be finely controlled according to each mode. As a result, the electric rotorcraft 10 according to one embodiment of the present invention is an electric rotorcraft that enables flight suitable for each mode, and the electric rotorcraft 10 according to one embodiment of the present invention is an electric rotorcraft that can reduce the pilot's piloting load. <1-2-6. Other processing>

[0084] 4, based on the first process, the second process, or the third process, a fourth process may cause the electric rotorcraft 10 to transition from the second state to a fourth state, a fifth process may cause the electric rotorcraft 10 to transition from the first state to the fourth state, and a sixth process may cause the electric rotorcraft 10 to transition from the first state to the third state. The electric rotorcraft 10 can be equipped with and execute various processes as appropriate depending on the application, specifications, etc. of the electric rotorcraft 10.

[0085] The flight control device 130 has a process for putting either the first motor 100A or the second motor 100B into an over-rotation state in which the rotation speed of the main rotor shaft 154 is greater than the rotation speed corresponding to the flight speed. If an unexpected event occurs to the electric rotorcraft 10, such as one of the electric motors being damaged and becoming uncontrollable or one of the electric motors being impaired in function, the lift of the electric rotorcraft 10 can be maintained or increased by the process for putting the electric rotorcraft 10 into an over-rotation state, thereby keeping the electric rotorcraft 10 in a safe state.

[0086] The flight control device 130 may also include a process for controlling the rotation speed of the first motor 100A, the second motor 100B, or each rotor shaft and the rotor pitch of the multiple rotor blades 170 according to the flight altitude of the electric rotorcraft 10 so as to reduce the rotation speed and increase the lift of the electric rotorcraft 10. The electric rotorcraft 10 according to one embodiment of the present invention has an electric motor with a large torque compared to rotorcraft using a conventional internal combustion engine, and therefore can reduce the rotation speed and change the rotor pitch. As a result, the lift of the electric rotorcraft 10 can be increased and noise associated with the rotation of the motor can be suppressed.

[0087] The embodiments, parts of the embodiments, processes, or parts of each process described above as the embodiments of the present invention can be implemented in any suitable combination as long as they are not mutually inconsistent.

[0088] Even if the effects and advantages brought about by the aspects of the above-described embodiment are different from those brought about by the above-described embodiment, if they are clear from the description in this specification or can be easily predicted by a person skilled in the art, they are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0089] 10: electric rotorcraft, 20: electric rotorcraft body, 30: main rotor system, 40: tail rotor system, 100: electric motor system, 100A: first motor, 100B: second motor, 102A: first motor control device, 102B: second motor control device, 104: bulkhead (support member), 105: one-way clutch, 110: power control system, 110A: first battery management system, 110B: second battery management system, 120A: first battery, 120B: second battery, 120C: third battery battery, 122: tail rotor control device, 130: flight control device, 140: flight control device, 142: input device, 144: display device, 150: reduction gear, 152: drive shaft (first power shaft), 154: main rotor shaft (first output shaft), 156: tail rotor shaft (second output shaft), 160: main rotor, 170: rotor blade (propeller), 172: main rotor control device, 180: tail rotor, 182: tail rotor control device, 200: electric motor system, 200A: third motor, 202A: third motor control device

Claims

1. A first output shaft; a main rotor system provided on the first output shaft and having a main rotor and rotor blades rotatable about an axis of the first output shaft; a power shaft that transmits power to the first output shaft; an electric motor system provided on the power shaft and configured to drive the main rotor system; a flight control device connected to the electric motor system, capable of selecting a first mode, a second mode, a third mode, and a fourth mode for flying an electric helicopter, controlling the electric motor system to maintain the rotation speed of the first output shaft at a rotation speed corresponding to each mode, and controlling the rotor pitch of the rotor blades to maintain a rotor pitch corresponding to each mode; An electric helicopter having: the first mode is a mode in which the electric helicopter is flown in a first flight state in which the rotation speed of the first output shaft is adjusted to a first rotation speed corresponding to the flight speed of the electric helicopter when ascending or descending in accordance with the flight speed of the electric helicopter, and a rotor pitch of the rotor blades corresponding to the flight speed is adjusted to a first rotor pitch corresponding to the flight speed of the electric helicopter when ascending or descending, the second mode is a mode in which the electric helicopter is flown in a second flight state in which the rotation speed of the first output shaft corresponding to the flight speed is adjusted to a second rotation speed such that the electric power for driving the electric helicopter corresponding to the flight speed of the electric helicopter is minimized, and the rotor pitch of the rotor blades corresponding to the flight speed is adjusted to a second rotor pitch such that the electric power for driving the electric helicopter corresponding to the flight speed of the electric helicopter is minimized, the third mode is a mode in which the electric helicopter is flown in a third flight state in which the rotation speed of the first output shaft corresponding to the flight speed is adjusted to a third rotation speed corresponding to the flight speed at which the electric helicopter is flown with a predetermined maximum surplus power, and the rotor pitch of the rotor blades corresponding to the flight speed is adjusted to a third rotor pitch corresponding to the flight speed at which the electric helicopter is flown with a predetermined maximum surplus power, so that the flight speed of the electric helicopter becomes the flight speed at a predetermined maximum surplus power; the fourth mode is a mode in which the rotation speed of the first output shaft according to the flight speed is adjusted to a fourth rotation speed that suppresses noise generated by the rotation of the main rotor and the rotor blades, the rotor pitch of the rotor blades according to the flight speed is adjusted to a fourth rotor pitch that suppresses noise generated by the rotation of the main rotor and the rotor blades, and the electric helicopter is flown in a fourth flight state in which noise generated by the rotation of the main rotor and the rotor blades is suppressed; the main rotor system includes a main rotor control device that receives a rotor pitch corresponding to the flight speed from the flight control device and adjusts a rotor pitch of the rotor blades to the rotor pitch corresponding to the flight speed; The flight control device transmits data on the number of rotations corresponding to the flight speed to the electric motor system, The electric motor system measures the rotation speed of the first output shaft and adjusts the rotation speed of the first output shaft to a rotation speed corresponding to the flight speed; the flight control device is capable of switching between the first mode and the second mode, between the first mode and the third mode, between the first mode and the fourth mode, between the second mode and the third mode, between the second mode and the fourth mode, and between the third mode and the fourth mode; Electric helicopter.

2. The electric motor system comprises: a first motor and a second motor provided on the power shaft to drive the main rotor system; A first motor control device connected to the first motor and configured to control the first motor so as to maintain a rotation speed of the first motor at a rotation speed corresponding to the flight speed; A second motor control device connected to the second motor and configured to control the second motor so as to maintain a rotation speed of the second motor at a rotation speed corresponding to the flight speed; 2. The electric helicopter according to claim 1, further comprising:

3. Equipped with a power supply device, The power supply device includes: a first battery electrically connected to the first motor controller and configured to provide power to the first motor and the first motor controller; a second battery electrically connected to the second motor controller and configured to power the second motor and the second motor controller; a third battery electrically connected to the flight control device and configured to provide power to the flight control device; 3. The electric helicopter according to claim 2, further comprising:

4. The flight control device causes either the first motor or the second motor to be in an over-rotation state in which the rotation speed of the first output shaft is greater than the rotation speed corresponding to the flight speed, The electric helicopter according to claim 3.

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