AIRCRAFT ACTUATOR, AIRCRAFT ACTUATOR DRIVE METHOD, AND AIRCRAFT ACTUATOR SYSTEM

Abstract

To provide an actuator for an aircraft capable of reducing the divergence of harmonic noise.SOLUTION: An actuator 100 includes an inverter 30, a stator 20, a mover 10, a control unit 36, an injection unit 50, a current detection unit 28, and an estimation unit 40. The inverter 30 is driven on the basis of electric power generated by the axial force of an engine or electric power of a battery or the like. The stator 20 has an armature coil 22 driven by the inverter 30. The mover 10 imparts driving force to at least one of a control surface of a tail of an aircraft 1, a movable wing of a main wing, a landing gear supporting a sliding wheel, and a liquid pump. The control unit 36 controls the inverter 30 in response to a signal from a control system 4. The injection unit 50 injects a high-frequency signal having a predetermined waveform into a coil 22. The current detection unit 28 detects a coil current. The estimation unit 40 estimates the position of the mover 10 on the basis of the coil current.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an actuator for an aircraft, a driving method for an actuator for an aircraft, and an actuator system for an aircraft. [Background technology]

[0002] Motors driven by inverters are known. For example, Patent Document 1 describes a three-phase variable speed motor driven by an inverter. This motor includes a voltage-type three-phase inverter that applies a three-phase voltage to the three-phase motor, and a controller that controls the inverter. The inverter has a plurality of legs driven by the controller. Each leg includes an upper arm switch and a lower arm switch. The multiple legs of the inverter are PWM switched. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-166924 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors have come to the following realization regarding aircraft actuators. By replacing conventional hydraulic actuators with electric actuators such as motors, it is possible to improve the fuel efficiency of aircraft. By driving the motor sensorlessly, the number of parts related to rotor position detection can be reduced and reliability can be improved. In sensorless driving, the armature coil is driven based on the rotor phase detected from the back electromotive force. However, since no back electromotive force is generated when the aircraft is stopped, the rotor phase cannot be detected, and the coil is driven with a phase unrelated to the rotor phase to start the motor. If the motor is driven with a phase unrelated to the rotor phase, it may reverse when starting the motor.

[0005] Aircraft actuators use a control system in which they output driving force for a short period of time from a stopped state and then stop again. With this control, if the actuator rotates in the reverse direction, the driven body moves in the reverse direction, causing the control to be disrupted. For this reason, aircraft actuators need to output driving force in the normal direction without reversing when started.

[0006] In order to prevent the reversal of rotation at startup, it is conceivable to detect the rotor phase from the change in the coil current of each phase when a high-frequency rectangular wave signal is injected. However, when a high-frequency rectangular wave signal is injected, harmonic noise is emitted from the coil. Large harmonic noise can adversely affect aircraft controlled by advanced radio equipment.

[0007] From this, the inventors recognized that there is room for improvement in aircraft actuators in terms of reducing harmonic noise.

[0008] The present invention has been made in consideration of these problems, and one of its objects is to provide an actuator for aircraft that can reduce the emission of harmonic noise. [Means for solving the problem]

[0009] In order to solve the above problems, an aircraft actuator according to one embodiment of the present invention includes an inverter driven by the power of the aircraft, a stator having an armature coil driven by electricity supplied to the inverter, a mover that applies driving force to at least one of the control surfaces of the aircraft's tail, the movable wings of the main wings, the landing gear supporting the wheels for running, and a liquid pump through magnetic interaction with the stator, a control unit that controls the operation of the inverter in response to a command signal from a control system of the aircraft, an injection unit that injects into the coil a high-frequency signal having any one of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a stepped manner between three or more levels, a current detection unit that detects a coil current flowing in the coil, and an estimation unit that estimates the position of the mover based on a component related to the high-frequency signal of the coil current detected by the current detection unit.

[0010] In addition, any combination of the above, or mutual substitution of the components or expressions of the present invention among methods, devices, programs, temporary or non-temporary storage media recording programs, systems, etc., are also valid aspects of the present invention. Effect of the Invention

[0011] According to the present invention, it is possible to provide an actuator for an aircraft that can reduce the emission of harmonic noise. [Brief description of the drawings]

[0012] [Figure 1] 1 is an explanatory diagram of an aircraft equipped with an aircraft actuator according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing an example of a configuration of the aircraft actuator of FIG. 1. [Diagram 3] 2 is a block diagram showing an example of a peripheral configuration of a control unit of an aircraft actuator in FIG. 1. FIG. [Figure 4] 2 is a block diagram showing an example of an estimation unit for an aircraft actuator in FIG. 1. [Diagram 5] FIG. 1 is a block diagram illustrating a first example of a form of injection of a high-frequency signal according to the present invention. [Figure 6] FIG. 4 is a block diagram illustrating a second example of a form of injection of a high-frequency signal according to the present invention. [Figure 7] FIG. 4 is a block diagram illustrating a third example of a form of injection of a high-frequency signal according to the present invention. [Figure 8] 4 is a waveform diagram showing an example of a waveform of a high-frequency signal with reduced harmonics. FIG. [Figure 9] 6 is a flowchart showing a method for driving an aircraft actuator according to a second embodiment of the present invention. [Figure 10] FIG. 11 is a block diagram showing a driver for an aircraft actuator according to a third embodiment of the present invention. [Figure 11] FIG. 11 is a block diagram showing an aircraft actuator system according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described below based on preferred embodiments with reference to the drawings. In the embodiments and modified examples, the same or equivalent components and members are given the same reference numerals, and duplicated descriptions are omitted as appropriate. The dimensions of the members in each drawing are enlarged or reduced as appropriate for ease of understanding. Some of the members that are not important for explaining the embodiments are omitted in each drawing.

[0014] In addition, terms including ordinal numbers such as first, second, etc. are used to describe various components, but these terms are used only for the purpose of distinguishing one component from another component, and the components are not limited by these terms.

[0015] [First embodiment] The configuration of an aircraft actuator 100 according to a first embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a schematic diagram showing a state in which the aircraft actuator 100 is installed in an aircraft 1. Fig. 2 is a block diagram showing an example of the configuration of the actuator 100. The aircraft actuator 100 is provided in the aircraft 1, and is used as an actuator that applies driving force to at least one of the following driven bodies: a control surface of the tail of the aircraft 1, a movable surface of the main wing, a leg supporting a wheel for running, and a liquid pump.

[0016] The movable surfaces of the main wing include the ailerons 2a and flaps 2b of the main wing. The control surfaces of the tail include the rudder 2c and elevator 2d of the tail. The landing gear supporting the wheels for running include the main landing gear 2f provided on the main wing and the fuselage landing gear 2g provided on the fuselage. The liquid pump includes the fuel pump 2j that supplies fuel to the engine 5 and the oil pump 2k that supplies hydraulic oil to the hydraulic mechanism.

[0017] When the actuator 100 performs intermittent stopping and starting operations, a slight time lag may occur in the operation. This time lag may cause the operation of the driven body 2 to become awkward, which may affect the attitude of the aircraft 1. Therefore, in this embodiment, the actuator 100 that drives the movable wing of the main wing or the control surface of the tail fin operates continuously while the aircraft 1 is flying, such as in horizontal flight, and stops operating while the aircraft is parked and the power supply of the aircraft is not activated. The actuator 100 that drives the movable wing of the main wing or the control surface of the tail fin may operate while the aircraft is parked if the power supply of the aircraft is activated.

[0018] In this embodiment, the actuator 100 that drives the landing legs operates continuously from immediately after takeoff during ascending flight and from descending flight until just before landing, and stops operating while the aircraft is parked and during horizontal flight. In this case, malfunction of the actuator 100 while the aircraft is parked and during horizontal flight can be prevented. The actuator 100 that drives the landing legs may operate while the aircraft is parked.

[0019] In this embodiment, the actuator 100 that drives the liquid pump operates continuously while the engine 5 is operating, and stops operating when the engine 5 is stopped while the aircraft is parked. In this case, it is possible to prevent the actuator 100 from malfunctioning while the engine is stopped. A separate power source for operating the actuator 100 while the engine is stopped is not required. The actuator 100 that drives the liquid pump may operate while the aircraft is parked.

[0020] The actuator 100 is driven based on the electric power of the aircraft 1. The electric power of the aircraft 1 can be electric power from various power supply means. As an example, the electric power of the aircraft 1 can be electric power generated by the generator 6 based on the shaft force of the engine 5 of the aircraft 1, electric power from a battery, electric power from an internal auxiliary power supply, electric power from a ram air turbine system, and the like. In this embodiment, the electric power of the aircraft 1 is electric power generated by the generator 6. The electric power of the generator 6 is supplied to the actuators 100 in each part of the fuselage of the aircraft 1 and a number of electronic devices including the flight control system 4 of the aircraft 1 through a power line 6b. If high-frequency noise generated by the actuator 100 leaks to the power line 6b, the noise may affect a number of electronic devices.

[0021] The actuator 100 operates in response to a command signal from the flight control system 4 to output a driving force. The flight control system 4 is disposed in the cockpit 7 or near the cockpit 7, and transmits a command signal to the actuator 100 via a transmission path 8. The transmission path 8 is routed along the wall of the fuselage to the actuators 100 in various parts of the fuselage of the aircraft 1. The wiring of the transmission path 8 is long, and the transmission path 8 passes near many electronic devices. If high-frequency noise generated by the actuator 100 leaks into the transmission path 8, the noise may affect many electronic devices.

[0022] The actuator 100 drives the driven body 2 via the transmission device 3. As an example, the transmission device 3 includes a reducer (not shown) that reduces the rotation, and a motion conversion device (not shown) that converts the output rotation of the reducer into linear motion. The motion conversion device is, for example, a ball screw. It is not essential to provide the transmission device 3.

[0023] When the actuator 100 operates, the driven body 2 is driven via a reducer and a motion conversion device, and the position and posture of the driven body 2 are changed. As an example, the actuator 100 is controlled to perform a driving operation for driving the driven body 2 and a holding operation for holding the position or posture of the driven body 2 in order to change the position or posture of the driven body 2. Therefore, the rotation angle (rotation position), rotation speed, and rotation acceleration of the actuator 100 are controlled so that the actuator 100 rotates temporarily during the driving operation for changing the position or posture of the driven body 2 and does not rotate during the holding operation. If the actuator 100 rotates in the reverse direction, the driven body 2 moves in the reverse direction and the position and posture are disturbed, so it is desirable that the actuator 100 is driven so as not to rotate in the reverse direction at the time of startup.

[0024] The main configuration of the actuator 100 will be described with reference to Fig. 2 as well. Each functional block shown in the block diagram including Fig. 2 can be realized in hardware by electronic elements and mechanical parts such as a computer CPU, and in software by a computer program, but the functional blocks realized by the cooperation of these are depicted here. Therefore, it will be understood by those skilled in the art that these functional blocks can be realized in various ways by combining hardware and software.

[0025] The actuator 100 mainly includes a mover 10, a stator 20, an inverter 30, an injection unit 50, a current detection unit 28, an estimation unit 40, and a control unit 36. The stator 20 has an armature coil 22 and faces the mover 10 in the radial direction via a magnetic gap. The mover 10 has an embedded magnet 10m, and the stator 20 and the mover 10 constitute an interior permanent magnet motor (IPM motor). In this example, the mover 10 functions as a rotor that rotates relative to the stator 20. In this example, the coils 22 include three-phase star-connected coils 22u, 22v, and 22w. The actuator 100 may be called a three-phase brushless motor or a three-phase synchronous motor.

[0026] The mover 10, through magnetic interaction with the stator 20, applies driving force to at least one of the control surfaces of the tail of the aircraft 1, the movable surfaces of the main wings, the landing gear supporting the wheels for running, and the liquid pump.

[0027] The inverter 30 is driven based on the electric power of the aircraft 1. The generator 6 may be a DC generator, but is an AC generator in this example. The electric power generated by the generator 6 is supplied to a voltage conversion unit 37 corresponding to the actuator 100 of each part via a power line 6b. The voltage conversion unit 37 rectifies the electric power supplied from the generator 6, converts it to a predetermined DC voltage Vp, and supplies it to the voltage supply unit 38. The voltage conversion unit 37 in this example includes a switching regulator. The voltage supply unit 38 generates a supply voltage Vs based on the supplied voltage Vp and supplies it to the inverter 30. The voltage supply unit 38 in this example includes an on / off unit 56 and a switching unit 58. The on / off unit 56 switches the supply voltage Vs between ON and OFF in response to the control of the control unit 36. The switching unit 58 lowers the supply voltage Vs in response to the control of the control unit 36.

[0028] The supply voltage Vs is supplied to a positive power supply line 30p of the inverter 30. Negative terminals 37g, 38g of the voltage conversion unit 37 and the voltage supply unit 38 are connected to a negative power supply line 30m of the inverter 30. The negative power supply line 30m is connected to the frame ground of the actuator 100.

[0029] The inverter 30 drives the coil 22 to generate a rotating magnetic field in the magnetic gap. The inverter 30 PWM-drives the coil 22 with a carrier frequency fc.

[0030] The inverter 30 includes a U-phase leg, a V-phase leg, and a W-phase leg connected between a positive power supply line 30p and a negative power supply line 30m. Each leg includes high-side arms T1 to T3 and low-side arms T4 to T6. The high-side arms T1 to T3 are connected to the positive power supply line 30p, and the low-side arms T4 to T6 are connected to the negative power supply line 30m.

[0031] In the inverter 30, when any of the high-side arms T1 to T3 is turned on, a drive current supplied from the positive power supply line 30p flows to the coil 22, and when any of the low-side arms T4 to T6 is turned on, the drive current flows from the coil 22 to the negative power supply line 30m.

[0032] These arms T1 to T6 are power transistors such as MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) or IGBTs (Insulated Gate Bipolar Transistors). These transistors may be made of Si (silicon), SiC (silicon carbide), GaN (gallium nitride), Ga2O3 (gallium oxide), etc.

[0033] The injection unit 50 injects a high-frequency signal Sh into the coil 22 in order to detect the rotation angle of the mover 10. In Fig. 2, the injection unit 50 is connected to the control unit 36 ​​for convenience, but there is no limitation on the injection point of the high-frequency signal Sh.

[0034] The high frequency signal Sh will now be described. From the viewpoint of reducing the emission of harmonic noise, the high frequency signal Sh has a harmonic reduced waveform in which harmonic components are reduced more than in a square wave. The harmonics are frequency components of higher order than the fundamental wave of the high frequency signal Sh. In other words, the harmonic reduced waveform is a waveform in which the harmonic content is lower than that of a square wave.

[0035] The harmonic reduction waveform of the high frequency signal Sh may be a sine wave, a triangular wave, a trapezoidal wave, or a step wave that changes in a step-like manner between three or more levels. In other words, the high frequency signal Sh has any of the waveforms of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a step-like manner between three or more levels. In this specification, the sine wave, triangular wave, and trapezoidal wave are not limited to strict triangular waves, trapezoidal waves, and sine waves, and include those that can be visually determined to be triangular waves, trapezoidal waves, and sine waves.

[0036] FIG. 8 shows waveform examples (a) to (d) of harmonic reduction waveforms. Waveform example (a) shows a sine wave waveform, waveform example (b) shows a triangular wave waveform, waveform example (c) shows a trapezoidal wave waveform, and waveform example (d) shows an example of a staircase waveform that changes in a step-like manner between three values. The harmonic reduction waveforms shown in waveform examples (a) to (d) can reduce harmonic noise in the high frequency signal Sh. In this embodiment, the high frequency signal Sh of the injection unit 50 has a staircase waveform that changes in a step-like manner between three values. For reference, a rectangular wave waveform that is not a harmonic reduction waveform is shown in waveform example (e).

[0037] The inventor's study has revealed that when a high-frequency signal Sh having a large time differential value (hereinafter simply referred to as "differential value") of the voltage or current is applied to the coil 22, the harmonic noise emitted from the coil 22 increases. In other words, it can be said that the harmonic noise can be reduced by reducing the differential value of the high-frequency signal Sh. In a waveform whose edges change in steps, such as a square wave or a staircase wave, if the time width of the edge is constant, the differential value decreases as the amplitude of each step decreases, so that the harmonic noise decreases. Therefore, it can be said that a staircase wave that changes in steps between N values ​​(an integer of N≧3) has smaller harmonic components than a square wave that changes in steps between two values. From these, the injection unit 50 of this embodiment injects a staircase wave that changes in steps between N values ​​(an integer of N≧3) as the high-frequency signal Sh. In this case, since the amplitude of each step is smaller than that of a square wave, the differential value can be reduced to reduce the emission of harmonic noise.

[0038] The staircase waveform shown in the waveform example (d) of FIG. 8 will be further explained. This staircase waveform changes in a stepwise manner among three levels, a first level L1, a second level L2, and a third level L3. In this waveform, the period at the first level L1 and the period at the third level L3 may be the same. Also, the period at the second level L2 may be the same as the period at the first level L1, or may be shorter or longer. For example, the period at the second level L2 may be in the range of 1 / 2 to 2 times the period at the first level L1. Simulations have suggested that the harmonic content is low within this range.

[0039] In this embodiment, the high-frequency signal Sh is a staircase wave that changes in steps among three levels: a first level L1, a second level L2 lower than the first level L1, and a third level L3 lower than the second level L2. When one period of the high-frequency signal Sh is taken as 100%, the period of the first level L1 and the period of the third level L3 are set to be greater than or equal to 10% and less than or equal to 40%.

[0040] The frequency fs of the high frequency signal Sh will be described. If the frequency fs is excessively low, the estimation accuracy of the rotation angle of the mover 10 decreases. For this reason, in this embodiment, the frequency fs of the high frequency signal Sh is set higher than the carrier frequency fc of the inverter 30. For example, when the carrier frequency fc of the inverter 30 is 6 kHz to 8 kHz, the frequency fs of the high frequency signal Sh may be 10 kHz or higher. If the frequency fs is excessively high, it is considered that the operation of the estimation unit 40 described later cannot keep up and malfunctions may occur. In the study by the present inventors, almost no malfunctions were observed when the frequency fs was in the range of 100 kHz or less.

[0041] The frequency fs of the high frequency signal Sh is preferably set to 10 kHz or more, more preferably 30 kHz or more, and further preferably 50 kHz or more. The frequency fs of the high frequency signal Sh is preferably set to 100 kHz or less. In a simulation, the desired estimation accuracy was obtained within this range, and the frequency of malfunctions was at a practical level.

[0042] If the mover 10 moves due to the injected high frequency signal Sh, the estimation accuracy of the rotation angle of the mover 10 decreases. For this reason, in this embodiment, the inverter 30 is controlled so that the mover 10 does not move when the high frequency signal Sh is injected. For example, by reducing the amplitude of the high frequency signal Sh, the movement of the mover 10 due to the high frequency signal Sh can be suppressed. Furthermore, by increasing the frequency fs of the high frequency signal Sh, the movement of the mover 10 due to the high frequency signal Sh can be suppressed. For these reasons, the amplitude and frequency fs of the high frequency signal Sh may be set within a range in which the mover 10 does not move due to the injection of the high frequency signal Sh. The range in which the mover 10 does not move may be a range in which it can be visually determined that the mover 10 does not move.

[0043] The current detection unit 28 will be described. As shown in FIG. 2, the current detection unit 28 includes current detection circuits 28u, 28v, and 28w that detect the phase currents of each phase flowing through the coils 22 of each phase. The current detection circuits 28u, 28v, and 28w output the phase currents Iu, Iv, and Iw as the detection results. The phase currents Iu, Iv, and Iw are collectively referred to as the detection current 28s. In other words, the current detection unit 28 outputs the detection current 28s as the detection result. As the current detection circuits 28u, 28v, and 28w, various current sensors such as DCCT (direct current transformer) and current sense resistors can be adopted. The current detection circuits 28u, 28v, and 28w of this embodiment are Hall element type current sensors that convert the magnetic field generated around the measured current into a voltage by utilizing the Hall effect. In this case, it is advantageous in that an output proportional to the current can be obtained from DC to high frequency.

[0044] The estimation unit 40 extracts information related to the high frequency signal Sh from the detection current 28s (phase currents Iu, Iv, Iw) of the current detection unit 28, estimates the rotation angle of the mover 10, etc. based on the extraction result, and outputs the estimation result 40e. Since the inductance of each phase of the coil 22 changes depending on the magnetic flux density received from the magnet 10m of the mover 10, the inductance can be obtained from the current of each phase and the rotation phase of the magnet 10m can be estimated based on the comparison result. The rotation angle of the mover 10 can be estimated based on the rotation phase of the magnet 10m. The angular acceleration and angular velocity of the mover 10 can be estimated by differentiating the rotation angle. The estimation unit 40 in this example outputs the angular acceleration, angular velocity, and rotation angle of the mover 10 as the estimation result. The angular acceleration, angular velocity, and rotation angle are collectively referred to as the estimation result 40e. The estimation unit 40 will be described later.

[0045] The control unit 36 ​​generates a drive waveform 36n for each phase based on the estimation result 40e (rotation angle of the mover 10) of the estimation unit 40 while monitoring the phase currents Iu, Iv, and Iw. The PWM modulation unit 32 generates an appropriate gate drive signal 32s for each phase at each time based on the drive waveform 36n, and switches the arms T1 to T6 (power transistors) of the inverter 30. The control method of the control unit 36 ​​is not particularly limited, and can be applied to square wave drive, sine wave drive, vector control, and the like. Of these, vector control is a method in which the current of the coil 22 of the actuator 100 is decomposed into orthogonal d-axis and q-axis components and each is individually controlled, and can be said to be a type of sine wave drive. Vector control has the advantage of high control efficiency, and is often used for high power applications.

[0046] Furthermore, the control unit 36 ​​controls the actuator 100 by feeding back the estimation result 40e based on a command signal 36s from the flight control system 4 of the aircraft 1. The control unit 36 ​​in this example executes sensorless vector control on the actuator 100. The command signal 36s may be any one of an angular acceleration, an angular velocity, and a rotation angle. Below, an example will be shown in which the command signal 36s is an angular velocity ωs.

[0047] FIG. 3 is a block diagram showing an example of the configuration of the periphery of the control unit 36. In this diagram, elements that are not important for the explanation of the control unit 36 ​​are omitted. Also, the connection lines in this diagram do not represent physical connections, but represent direct or indirect cooperation between functional blocks. Symbol M indicates the stator 20, the mover 10, the PWM modulation unit 32, the inverter 30, and the current detection unit 28 as a whole, and outputs the detection current 28s (phase currents Iu, Iv, Iw) of the current detection unit 28. The 3-2 phase converter 36g generates a d-axis current Id and a q-axis current Iq from the three phase currents Iu, Iv, Iw.

[0048] The estimation unit 40 estimates the angular acceleration Ae, angular velocity ωe, and rotation angle θe of the mover 10 from the d-axis current Id, the q-axis current Iq, the d-axis voltage Vd, and the q-axis voltage Vq. The speed controller 36c determines the drive current based on a comparison result between the angular velocity ωs of the command signal 36s and the estimated angular velocity ωe.

[0049] The current controller 36d determines the drive voltage based on the result of comparison between the speed controller 36c and the d-axis current Id and the q-axis current Iq. The separator 36e determines the d-axis voltage Vd and the q-axis voltage Vq based on the result of comparison between the speed controller 36c and the d-axis current Id, the q-axis current Iq, and the estimated rotation angle θe. The 2-3 phase converter 36f generates a three-phase drive waveform 36n based on the d-axis voltage Vd and the q-axis voltage Vq and outputs it to the PWM modulation unit 32.

[0050] In Fig. 3, for convenience, the injection unit 50 is connected to the input side of the current controller 36d, but there is no limitation on the injection point of the high frequency signal Sh. In the example of Fig. 3, the injection unit 50 inputs the high frequency signal Sh to the current controller 36d as a d-axis high frequency current Idh and a q-axis high frequency current Iqh. In this way, the high frequency signal Sh is injected into the coil 22 by inputting the high frequency current.

[0051] The estimation unit 40 will be described. FIG. 4 is a block diagram showing an example of the configuration of the estimation unit 40. In this diagram, elements that are not important for the description of the estimation unit 40 are omitted. Also, the connection lines in this diagram do not represent physical connections, but represent direct or indirect cooperation between functional blocks. Here, a method of estimating the rotation angle of the mover 10 by utilizing phase information of instantaneous reactive power due to injection of high-frequency current will be described.

[0052] In the example of Fig. 4, the estimation unit 40 estimates the angular acceleration Ae, the angular velocity ωe, and the rotation angle θe based on the d-axis current Id and the q-axis current Iq, which are the detected currents, and the d-axis voltage Vd and the q-axis voltage Vq, which are the voltage command values. The estimation unit 40 includes a bandpass filter 40b that extracts frequency components centered on the high-frequency signal Sh, an EXOR calculator 40f, a sample-and-hold unit 40h, integrators 40j and 40k, and an up-down counter 40m. The bandpass filter 40b passes mainly components related to the high-frequency signal Sh, and removes DC components (offset) and noise components.

[0053] As shown in Fig. 4, in the estimation unit 40, the d-axis current Id, the q-axis current Iq, the d-axis voltage Vd, and the q-axis voltage Vq, from which the DC component and the noise component have been removed by the band-pass filter 40b, are synthesized through a multiplier and an adder, and the offset is further removed to obtain a high-frequency reactive power 40d and a reference phase signal 40c. In addition, an exclusive OR 40g of the high-frequency reactive power 40d and the reference phase signal 40c is sampled and held, and processed by an integrator 40j to generate an estimated angular acceleration Ae. In addition, the estimated angular acceleration Ae is further processed by an integrator 40k to generate an estimated angular velocity ωe. In addition, the estimated angular velocity ωe is processed by an up-down counter 40m to generate an estimated rotation angle θe.

[0054] Next, the injection form of the high frequency signal Sh will be described. Fig. 5 is a block diagram illustrating a first example of the injection form of the high frequency signal Sh. In the first example, the high frequency signal Sh is injected into the positive side power supply line 30p of the inverter 30.

[0055] The mixer 52 mixes the high frequency signal Sh from the injection unit 50 with the supply voltage Vs. The mixer 52 may have any configuration capable of mixing the high frequency signal Sh, and may employ various known configurations. In this example, the mixer 52 mixes the high frequency signal Sh with the supply voltage Vs using a diode (not shown). The mixer 52 is provided between the voltage supply unit 38 and the positive power supply line 30p, and supplies the supply voltage Vs on which the high frequency signal Sh is superimposed to the positive power supply line 30p.

[0056] If the voltage of the high frequency signal Sh is lower than the supply voltage Vs, it is difficult to inject the high frequency signal Sh. Therefore, in this embodiment, the voltage of the high frequency signal Sh is set to be higher than the supply voltage Vs.

[0057] If the supply voltage Vs is higher than the high frequency signal Sh, it is difficult to inject the high frequency signal Sh. Therefore, the voltage supply unit 38 of this embodiment has a switching unit 58 that lowers the supply voltage Vs to the inverter 30 when injecting the high frequency signal Sh. For example, the switching unit 58 supplies the voltage Vp of the voltage conversion unit 37 as the supply voltage Vs as is when the high frequency signal Sh is not injected, and lowers the supply voltage Vs to a voltage lower than the voltage Vp when the high frequency signal Sh is injected. For example, the switching unit 58 may make the supply voltage Vs lower than the high frequency signal Sh when the high frequency signal Sh is injected.

[0058] The switching unit 58 may have various known configurations as long as it is capable of lowering the supply voltage Vs of the voltage supply unit 38. The switching unit 58 in this example has a configuration that lowers the supply voltage Vs by combining a semiconductor switch and a voltage divider circuit (both not shown).

[0059] From the viewpoint of facilitating the injection of the high frequency signal Sh, the supply voltage Vs may be turned off when the high frequency signal Sh is injected. For this reason, this embodiment has an on / off unit 56 that turns off the supply voltage Vs of the voltage supply unit 38 of the inverter 30 when the high frequency signal Sh is injected. The on / off unit 56 may have any configuration that can switch the supply voltage Vs on and off, and various known configurations can be adopted. The on / off unit 56 in this example switches the supply voltage Vs on and off by a semiconductor switch (not shown).

[0060] For the first example, an operation for estimating the rotation angle of the mover 10 in a stopped state will be described. (1) In a stopped state, the supply voltage Vs is turned off by the on / off unit 56, and the high frequency signal Sh is injected from the injection unit 50 via the mixer 52 into the positive power supply line 30p of the inverter 30.

[0061] (2) In this state, one or two of the high-side arms T1 to T3 of the inverter 30 are turned on, and one or two of the low-side arms T4 to T6 are turned on. At this time, control is performed so that the high-side arm and the low-side arm are not turned on simultaneously in one phase leg. Here, a case where the high-side arms T1, T2 and the low-side arm T6 are turned on will be described.

[0062] (3) The high-frequency signal Sh is supplied from the turned-on high-side arms T1, T2 to the coils 22u, 22v, passes through the coil 22w, and flows from the low-side arm T6 to the negative power supply line 30m.

[0063] (4) At this time, the current detection unit 28 detects the current in the coil 22 and outputs the detected current 28s to the estimation unit 40. (5) The estimator 40 estimates the rotation angle of the mover 10 in accordance with the detected current 28s and the on state of the inverter 30, and outputs the estimated rotation angle θe to the controller .

[0064] (6) The control unit 36 ​​determines a drive waveform 36n based on the estimated rotation angle θe. The drive waveform 36n includes information on the arms of the inverter 30 to be turned on and the arms to be turned off. (7) The control unit 36 ​​turns on the supply voltage Vs to operate the inverter 30, supplies a drive current to the coil 22, and rotates the mover 10.

[0065] (8) When the mover 10 rotates, the inverter 30 may be controlled based on the back electromotive force of the coil 22. In this embodiment, however, a high-frequency signal Sh is injected at a predetermined timing to control the inverter 30 based on the estimated rotation angle θe of the estimator 40.

[0066] Next, a second example of the injection form of the high frequency signal Sh will be described. Fig. 6 is a block diagram illustrating the second example of the injection form of the high frequency signal Sh. In the second example, the high frequency signal Sh is injected between the inverter 30 and the coil 22. The second example differs from the first example in the configuration of the mixer 52, but the configurations of the switching unit 58 and the on / off unit 56 are the same. Therefore, the differences in the mixer 52 and operation will be described.

[0067] 6, the first to third mixing sections 52u, 52v, 52w are interposed between the outputs of the U-phase leg, the V-phase leg, and the W-phase leg of the inverter 30 and the coils 22u, 22v, 22w of each phase, and directly inject the high-frequency signal Sh into the coil 22.

[0068] When the high frequency signal Sh is injected between the inverter 30 and the coil 22, it is considered that the high frequency signal Sh of the injection unit 50 may interfere with the operation of the inverter 30. For this reason, in this embodiment, when the high frequency signal Sh is injected between the inverter 30 and the coil 22, a part or all of the inverter 30 is turned off. For example, at this time, one or both of the high side arms T1 to T3 and the low side arms T4 to T6 of the inverter 30 may be turned off. Note that in order to secure a current path to the negative side power supply line 30m of the injected high frequency signal Sh, a part of the low side arms may be turned on at a predetermined timing.

[0069] A third example of the injection form of the high frequency signal Sh will be described. Fig. 7 is a block diagram illustrating a third example of the injection form of the high frequency signal Sh. In the third example, the high frequency signal Sh is injected into the output of the inverter 30. In the third example, the configurations and operations of the switching unit 58 and the on / off unit 56 are similar to those in the second example.

[0070] 7, the injection unit 50 has transistors T11, T12, T13, T14, T15, and T16 that are separate from the transistors of the inverter 30, and a signal generating unit 50g. The transistors T11 to T16 in this example are power transistors. In this example, when the high-frequency signal Sh is injected, some of the high-side arms T1 to T3 and low-side arms T4 to T6 of the inverter 30 are turned off, and the high-frequency signal Sh is injected from the transistors T11 to T16 to the coil 22.

[0071] The injection unit 50 includes three legs corresponding to each phase. Each leg includes high-side transistors T11 to T13 connected to a positive line 50p and low-side transistors T14 to T16 connected to a negative line 50m. Leg output units Q1 to Q3 are provided at the connection points between the emitters of the high-side transistors T11 to T13 and the collectors of the low-side transistors T14 to T16. The leg output units Q1 to Q3 of each phase are connected to the coils 22u, 22v, and 22w of each phase. The bases of the transistors T11 to T16 are connected to a signal generating unit 50g.

[0072] The signal generating section 50g generates an original signal for outputting a high-frequency signal Sh having a predetermined waveform from the leg output sections Q1 to Q3. Each leg functions as an amplifier for amplifying the original signal generated by the signal generating section 50g.

[0073] The positive line 50p is connected to the voltage conversion unit 37 and is supplied with a voltage Vp. The negative line 50m is connected to a negative terminal 37g of the voltage conversion unit 37. When the bases of the transistors T11 to T16 are driven by the signal generating unit 50g, a high-frequency signal Sh having a staircase waveform that changes in a stepped manner among three levels, a first level L1, a second level L2, and a third level L3, is output to the leg output units Q1 to Q3. This high-frequency signal Sh is injected into the coils 22u, 22v, and 22w.

[0074] The transistors T11 to T16 are power transistors such as MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) or IGBTs (Insulated Gate Bipolar Transistors). These transistors may be made of Si (silicon), SiC (silicon carbide), GaN (gallium nitride), Ga2O3 (gallium oxide), etc. The transistors T11 to T16 may be the same transistors as the arms T1 to T6.

[0075] When the high frequency signal Sh is injected into the output of the inverter 30, it is considered that the high frequency signal Sh of the injection unit 50 may interfere with the operation of the inverter 30. For this reason, in this embodiment, when the high frequency signal Sh is injected into the output of the inverter 30, a part or all of the inverter 30 is turned off. For example, at this time, one or both of the high side arms T1 to T3 and the low side arms T4 to T6 of the inverter 30 may be turned off. Note that in order to secure a current path to the negative side power supply line 30m of the injected high frequency signal Sh, some of the low side arms may be turned on at a predetermined timing.

[0076] The fluctuation detection unit 44 and the correction unit 46 will be described with reference to Fig. 2. There is a possibility that an error is included in the estimation result 40e of the estimation unit 40 due to slight fluctuations or noise in the power supply. This error may affect the attitude of the aircraft 1 through the operation of the driven body 2. Therefore, the actuator 100 of this embodiment includes a fluctuation detection unit 44 that monitors the estimation result 40e of the estimation unit 40 and detects an abnormality in the estimation result 40e, and a correction unit 46 that corrects the estimation result 40e based on the detection result 44e of the fluctuation detection unit 44.

[0077] The fluctuation detection unit 44 monitors the estimation result 40e and detects a sudden fluctuation of the estimation result 40e that exceeds a predetermined range. For example, the fluctuation detection unit 44 generates a model by machine learning the fluctuation pattern of the estimation result 40e under normal conditions, calculates the deviation rate of the estimation result 40e from the fluctuation pattern under normal conditions using the model, and determines that an abnormality has occurred if the deviation rate exceeds a threshold value.

[0078] When the fluctuation detection unit 44 detects an abnormality in the estimation result 40e, the correction unit 46 generates a correction value 46e for correcting the estimation result 40e. The correction unit 46 superimposes the correction value 46e on the estimation result 40e so as to mitigate the abnormal fluctuation in the estimation result 40e. As a result, the influence on the attitude of the aircraft 1 caused by the abnormality in the estimation result 40e can be reduced.

[0079] The diagnosis unit 47 will be described with reference to FIG. 2. The actuator 100 includes the diagnosis unit 47 for self-diagnosis. As an example, the diagnosis unit 47 transmits to the control system 4 a result of diagnosing the state of the actuator 100 based on the coil currents Iu, Iv, and Iw detected by the current detection unit 28. The diagnosis unit 47 monitors the change patterns of the coil currents Iu, Iv, and Iw, and diagnoses whether or not the change patterns of the currents are within a steady range. For example, the diagnosis unit 47 generates a model by machine learning the change patterns of the currents in a normal state, and uses the model to obtain a deviation rate of the change patterns of the currents from the normal fluctuation patterns, and determines that an abnormality exists if the deviation rate exceeds a threshold value. The diagnosis unit 47 transmits at least one of the deviation rate and the determination result to the control system 4 as a diagnosis result 47e. The control system 4 can perform a predetermined operation according to the diagnosis result 47e. For example, the control system 4 supplies a switching command signal 48c to the switching unit 48 according to the diagnosis result 47e.

[0080] The switching unit 48 will be described with reference to Fig. 2. From the viewpoint of reducing the failure rate of the actuator 100, it is desirable to duplicate each component of the actuator 100. In the actuator 100, each component is duplicated into a master and a slave, and these are configured to be switchable. In particular, in the actuator 100, at least one of the inverter 30, the armature coil 22, the mover 10, the control unit 36, the injection unit 50, the current detection unit 28, and the estimation unit 40 is duplicated into a master and a slave.

[0081] 2, the master 48m is at least one of the inverter 30, the armature coil 22, the mover 10, the control unit 36, the injection unit 50, the current detection unit 28, and the estimation unit 40 (hereinafter referred to as the "master component"). The slave 48s is a switching component (hereinafter referred to as the "slave component") corresponding to the master component of the master 48m. In other words, the slave component is a component for backing up the master component.

[0082] The switching unit 48 switches between the master component and the slave component in response to the diagnosis result 47e of the diagnosing unit 47 or a switching command signal 48c from the flight control system 4. When the diagnosis result 47e of the diagnosing unit 47 indicates a normal state, the switching unit 48 selects the master component, and the actuator 100 operates using the master component. When the diagnosis result 47e of the diagnosing unit 47 indicates an abnormal state, the switching unit 48 switches to the slave component, and the actuator 100 operates using the slave component. In other words, the actuator 100 can back up each component when an abnormal state occurs.

[0083] Next, features of an aircraft actuator 100 according to a first embodiment of the present invention will be described. The actuator 100 includes an inverter 30 driven based on the power of the aircraft 1, a stator 20 having an armature coil 22 driven by energization of the inverter 30, a mover 10 that applies driving force to at least one of the control surfaces of the tail of the aircraft 1, the movable wings of the main wings, the landing gear supporting the wheels for running, and a liquid pump by magnetic interaction with the stator 20, a control unit 36 ​​that controls the operation of the inverter 30 in response to a command signal 36s from a flight control system 4 of the aircraft 1, an injection unit 50 that injects into the coil 22 a high-frequency signal Sh having any one of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a stepped manner between three or more levels, a current detection unit 28 that detects coil currents Iu, Iv, Iw flowing through the coil 22, and an estimation unit 40 that estimates the position of the mover 10 based on the components of the coil currents Iu, Iv, Iw detected by the current detection unit 28 that are related to the high-frequency signal Sh.

[0084] According to this configuration, since the high frequency signal Sh having a harmonic reduced waveform is used, the emission of harmonic noise that adversely affects electronic devices of the aircraft 1 can be suppressed, and adverse effects on the aircraft 1 can be suppressed.

[0085] The actuator 100 is configured to operate continuously after activation. In this case, since the actuator 100 operates continuously, there is no time lag due to restarting, and the driven body 2 operates smoothly.

[0086] The actuator 100 is configured to stop operating while the aircraft 1 is parked. In this case, deterioration of the actuator 100 can be suppressed, and the failure rate can be reduced.

[0087] The actuator 100 includes a diagnosis unit 47 that diagnoses the state of the actuator based on the coil currents Iu, Iv, and Iw detected by the current detection unit 28 and transmits the result of the diagnosis to the control system 4. In this case, the actuator 100 can self-diagnose the deterioration state of each part. The control system 4 can notify the diagnosis result.

[0088] In the actuator 100, at least one of the inverter 30, the armature coil 22, the mover 10, the control unit 36, the injection unit 50, the current detection unit 28, and the estimation unit 40 is duplicated into a master 48m and a slave 48s, and a switching unit 48 is provided for switching between the master 48m and the slave 48s according to the diagnosis result 47e of the diagnosis unit 47. In this case, since each component of the actuator 100 is duplicated, the failure rate can be reduced. The actuator 100 can also automatically switch from the master 48m to the slave 48s according to the diagnosis result 47e. In addition, when the master 48m and the slave 48s are operating in synchronization, if a problem occurs in either one, the switching unit 48 can also stop the master 48m or the slave 48s according to the diagnosis result 47e of the diagnosis unit 47. Note that the master 48m and the slave 48s are not included as components of the actuator, and the system of the actuator itself may be stopped using a judgment unit having a judgment function for stopping the system of the actuator itself, without going through the switching unit, according to the diagnosis result 47e of the diagnosis unit 47.

[0089] The actuator 100 includes a fluctuation detection unit 44 that monitors the estimation result 40e of the estimation unit 40 and detects an abnormality in the estimation result 40e, and a correction unit 46 that corrects the estimation result 40e based on the detection result 44e of the fluctuation detection unit 44. In this case, when the estimation result 40e is abnormal, the estimation result 40e is corrected, and the effect on the attitude of the aircraft 1 can be reduced.

[0090] In the actuator 100, the injection unit 50 has other transistors T11-T16 connected to the output of the inverter 30 in addition to the inverter 30, and injects the high frequency signal Sh from the other transistors T11-T16 to the coil 22. In this case, the high frequency signal Sh can be directly injected to the coil 22. Since it is injected from a separate transistor, the high frequency signal Sh of a desired level can be easily injected. Since the wiring distance to the coil 22 can be shortened, the leakage of harmonic noise can be reduced.

[0091] In the actuator 100, the amplitude and frequency of the high frequency signal Sh are set within a range that does not move the mover 10. In this case, it is possible to prevent malfunction of the actuator 100 due to injection of the high frequency signal Sh.

[0092] In the actuator 100, the frequency of the high frequency signal Sh is set to be higher than the carrier frequency of the inverter 30. In this case, the accuracy of estimating the position of the mover 10 is increased, making it possible to prevent malfunction of the actuator.

[0093] In the actuator 100, the high frequency signal Sh is a step wave that changes stepwise among three levels: a first level L1, a second level L2 lower than the first level L1, and a third level L3 lower than the second level L2, and when one period of the high frequency signal Sh is taken as 100%, the period of the first level L1 and the period of the third level L3 are set to be 20% or more and 40% or less. In this case, the harmonic noise contained in the high frequency signal Sh can be reduced.

[0094] The above is a description of the first embodiment.

[0095] [Second embodiment] Next, a method S100 for driving an aircraft actuator 100 according to a second embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is a flowchart showing a method S100 for driving an aircraft actuator 100. In the description and drawings of the second embodiment, components and members that are the same as or equivalent to those in the first embodiment are given the same reference numerals. Descriptions that overlap with the first embodiment will be omitted as appropriate, and the following description will focus on configurations that differ from the first embodiment.

[0096] A driving method S100 of this embodiment includes a step S102 of injecting, into the armature coil 22 of the actuator 100, a high-frequency signal Sh having any one of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a stepped manner between three or more levels, a detection step S104 of detecting coil currents Iu, Iv, Iw flowing through the coil 22, and an estimation step S106 of estimating the position of the mover 10 based on components of the coil currents Iu, Iv, Iw detected in the detection step S104 that are related to the high-frequency signal Sh.

[0097] The driving method S100 further includes step S108 of generating a driving waveform 36n, step S110 of generating a gate driving signal 32s, and step S112 of switching the arms T1 to T6 of the inverter 30. In step S108, the control unit 36 ​​generates a driving waveform 36n for each phase based on the rotation angle θe of the mover 10 estimated in step S106 while monitoring the phase currents Iu, Iv, and Iw. In step S110, the PWM modulation unit 32 generates an appropriate gate driving signal 32s for each phase at each time based on the driving waveform 36n. In step S112, the PWM modulation unit 32 switches the arms T1 to T6 of the inverter 30 by the gate driving signal 32s.

[0098] By switching the arms T1 to T6, a drive current flows through the coil 22, driving the aircraft actuator 100. This flow is merely an example, and other steps may be added, some steps may be changed or deleted, or the order of the steps may be changed.

[0099] According to the second embodiment, it is possible to obtain the same functions and effects as the first embodiment.

[0100] [Third embodiment] Next, a driver 60 for an aircraft actuator according to a third embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 is a block diagram showing the driver 60. In the description and drawings of the third embodiment, components and members that are the same as or equivalent to those in the first embodiment are given the same reference numerals. Descriptions that overlap with the first embodiment will be omitted as appropriate, and the following description will focus on configurations that differ from the first embodiment.

[0101] The driver 60 is a circuit unit including an inverter 30, an injection unit 50, a current detection unit 28, an estimation unit 40, and a control unit 36. The driver 60 can be configured as a one-chip or multi-chip driver IC. The driver 60 may further include a fluctuation detection unit 44 and a correction unit 46. The driver 60 may further include a diagnosis unit 47 and a switching unit 48.

[0102] According to the third embodiment, it is possible to obtain the same functions and effects as the first embodiment.

[0103] [Fourth embodiment] Next, an aircraft actuator system 200 according to a fourth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is a block diagram showing the aircraft actuator system 200. In the description and drawings of the fourth embodiment, components and members that are the same as or equivalent to those of the first embodiment are given the same reference numerals. Descriptions that overlap with the first embodiment will be omitted as appropriate, and the description will focus on configurations that differ from the first embodiment. In the description of the fourth embodiment, a number of components will be distinguished from one another by adding "-A" or "-B" to the end of the reference numerals.

[0104] The aircraft actuator system 200 includes a first actuator 100-A and a second actuator 100-B, which are the aircraft actuators 100 of the first embodiment that drive a common driven body, a first voltage supply unit 38-A that drives the first actuator 100-A, and a second voltage supply unit 38-B that is separate from the first voltage supply unit 38-A and drives the second actuator 100-B. The first voltage supply unit 38-A and the second voltage supply unit 38-B may supply voltages based on electric power generated by axial forces of different engines, or may supply voltages based on electric power generated by axial forces of a common engine. In addition, the first voltage supply unit 38-A and the second voltage supply unit 38-B may supply voltages based on electric power from different batteries, or may supply voltages based on electric power from a common battery.

[0105] The first actuator 100-A and the second actuator 100-B may be controlled based on a common command signal 36s from the flight control system 4 of the aircraft 1, or may be controlled based on separate command signals. The first actuator 100-A and the second actuator 100-B are configured to drive a common driven body via a common transmission device.

[0106] According to the fourth embodiment, it is possible to obtain the same functions and effects as those of the first embodiment. In addition, in the fourth embodiment, the voltage supply unit 38 and the actuator 100 are duplicated, so that even if one of the voltage supply units or actuators fails, the other voltage supply unit and actuator will operate and perform the specified function, thereby reducing the failure rate of the system.

[0107] Above, examples of the embodiments of the present invention have been described in detail. The above-mentioned embodiments merely show specific examples of implementing the present invention. The contents of the embodiments do not limit the technical scope of the present invention, and many design changes such as changing, adding, and deleting components are possible within the scope of the invention as defined in the claims. In the above-mentioned embodiments, the contents for which such design changes are possible are described with the notation "of the embodiment" or "in the embodiment", but this does not mean that design changes are not permitted for contents without such notation.

[0108] [Variations] The following describes the modified examples. In the description and drawings of the modified examples, the same or equivalent components and members as those in the embodiment are denoted by the same reference numerals. Explanations that overlap with the embodiment will be omitted as appropriate, and the description will focus on the configurations that differ from the first embodiment.

[0109] In the description of the first embodiment, an example was shown in which the frequency of the high frequency signal Sh is constant and does not change on the time axis, but the present invention is not limited to this. For example, the frequency of the high frequency signal Sh may change periodically on the time axis. By periodically changing the frequency of the high frequency signal Sh, the frequency of harmonic noise is dispersed, and the noise peak generated in a specific frequency range can be suppressed on the time axis.

[0110] In the explanation of the first embodiment, an example in which the mover 10 rotates has been shown, but the present invention is not limited to this. For example, the mover may move linearly.

[0111] In the description of the first embodiment, an example has been shown in which the armature coil 22 is three-phase, but the present invention is not limited to this. The armature coil may be two-phase or four or more phases.

[0112] In the description of the first embodiment, an example was given in which the actuator 100 is an embedded magnet motor, but the present invention is not limited to this. For example, the actuator may be a surface magnet motor or other types of motors.

[0113] In the description of the first embodiment, an example has been given in which the actuator 100 operates continuously during flight, such as horizontal flight, of the aircraft 1, but the present invention is not limited to this. The actuator may operate intermittently during flight, such as horizontal flight. In this case, deterioration of the actuator can be suppressed.

[0114] In the description of the first embodiment, an example has been given in which the actuator 100 stops operating while the aircraft 1 is parked, but the present invention is not limited to this. The actuator may operate even while the aircraft is parked. In this case, the influence of a time lag due to restart is eliminated.

[0115] Each of the above-mentioned modified examples can obtain the same functions and effects as the first embodiment.

[0116] Any combination of the above-described embodiments and modifications is also useful as an embodiment of the present invention. A new embodiment resulting from the combination has the combined effects of the respective embodiments and modifications. [Explanation of symbols]

[0117] 1...aircraft, 10...mover, 20...stator, 22...coil, 28...current detection unit, 28s...detected current, 30...inverter, 36...control unit, 38...voltage supply unit, 40...estimation unit, 50...injection unit, 52...mixing unit, 56...on / off unit, 58...switching unit, 60...driver, 100...aircraft actuator, S100...driving method, 200...aircraft actuator system.

Claims

1. Inverter based on aircraft power; a stator having an armature coil that is energized and driven by the inverter; a movable member that applies a driving force to at least one of a control surface of a tail of the aircraft, a movable surface of a main wing, a landing gear supporting a wheel for running, and a liquid pump by magnetic interaction with the stator; a control unit that controls an operation of the inverter in response to a command signal from a flight control system of the aircraft; an injection unit that injects into the coil a high-frequency signal having any one of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a stepped manner between three or more levels; A current detection unit that detects a coil current flowing through the coil; an estimation unit that estimates a position of the mover based on a component of the coil current detected by the current detection unit that is related to the high frequency signal; a diagnosis unit that diagnoses a state of the actuator based on the coil current detected by the current detection unit and transmits the result to the flight control system; Equipped with An aircraft actuator configured to operate continuously after activation.

2. 2. The actuator for an aircraft according to claim 1, wherein a result of diagnosing the state of the actuator is information indicating normality or information indicating abnormality.

3. 3. The aircraft actuator according to claim 1, wherein at least one of the inverter, the coil, the mover, the control unit, the injection unit, the current detection unit and the estimation unit is duplicated into a master and a slave, and the actuator further comprises a switching unit that switches between the master and the slave in response to a diagnosis result of the diagnosing unit.

4. a fluctuation detection unit that monitors an estimation result of the estimation unit and detects an abnormality in the estimation result; a correction unit that corrects the estimation result based on a detection result of the fluctuation detection unit. The actuator for an aircraft according to any one of claims 1 to 3.

5. The injection unit has another transistor connected to an output of the inverter separately from the inverter, and injects the high frequency signal from the other transistor into the coil. The actuator for an aircraft according to any one of claims 1 to 4.

6. The amplitude and frequency of the high frequency signal are set within a range in which the movable element does not move. The actuator for an aircraft according to any one of claims 1 to 5.

7. The frequency of the high frequency signal is set higher than the carrier frequency of the inverter.

7. An actuator for an aircraft according to claim 6.

8. the high-frequency signal is a step wave that changes in a stepwise manner among three levels: a first level, a second level lower than the first level, and a third level lower than the second level, When one period of the high frequency signal is taken as 100%, the period of the first level and the period of the third level are set to 10% or more and 40% or less. An actuator for an aircraft according to any one of claims 1 to 7.

9. a coil of an aircraft actuator configured to operate continuously after being started, the coil including an inverter driven based on the electric power of the aircraft, a stator having an armature coil driven by energization of the inverter, a mover that applies a driving force to at least one of a control surface of a tail of the aircraft, a movable surface of a main wing, a landing gear supporting a wheel for running, and a liquid pump by magnetic interaction with the stator, and a control unit that controls the operation of the inverter in response to a command signal from a flight control system of the aircraft, A step of injecting a high-frequency signal having any one of a sine wave, a trapezoidal wave, a triangular wave, and a step wave that changes in a stepped manner between three or more levels; a control step of controlling an operation of the inverter in response to a command signal from a flight control system of the aircraft; a detection step of detecting a coil current flowing through the coil; an estimation step of estimating a position of the mover based on a component of the coil current related to the high frequency signal detected in the detection step; a diagnosis step of diagnosing a state of the actuator based on the coil current detected in the detection step and transmitting the result to the flight control system; A method for driving an actuator for an aircraft, comprising:

10. a first actuator and a second actuator which are the aircraft actuators according to claim 1 and drive a common driven body; a first voltage supply unit that drives the first actuator; a second voltage supply unit that is separate from the first voltage supply unit and drives the second actuator; An actuator system for an aircraft comprising:

Images