Monitoring device, monitoring method, and program

Abstract

To provide a monitoring device capable of increasing flight safety.SOLUTION: A monitoring device 50 monitors a battery 14 mounted on an eVTOL. The monitoring device 50 includes an acquisition unit 51, and an output unit 53. The acquisition unit 51 acquires voltage information of battery 14 during flight and information on eVTOL transportation modes. When specified conditions regarding the abnormality of battery 14 are met, the output unit 53 outputs monitoring results by using voltage information, and thresholds set for each movement mode. Since the thresholds set for each travel mode are used, abnormalities in the battery 14 can be detected in an early stage thereby enhancing flight safety.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The disclosure in this specification relates to a monitoring device, a monitoring method, and a program. [Background technology]

[0002] Patent Document 1 discloses a method for controlling an electric flying object. The contents of the prior art documents are incorporated by reference as explanations of technical elements in this specification. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2021-172101 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the battery state is monitored, and measures to avoid an abnormality such as a short circuit are taken after the abnormality is detected. In the above-mentioned respects and in other respects not mentioned, further improvements are required in the monitoring device, the monitoring method, and the program.

[0005] One disclosed objective is to provide a monitoring device, a monitoring method, and a program that can improve flight safety. [Means for solving the problem]

[0006] One aspect of the disclosure is A monitoring device for monitoring a battery (14) mounted on an electric flying object (10), comprising: an acquisition unit (51) that acquires battery voltage information during flight and information related to a travel mode of the electric flying object; an output unit (53) that outputs a monitoring result when a predetermined condition related to a battery abnormality is satisfied using the voltage information and a threshold value set for each travel mode; Equipped with.

[0007] When an electric flying object moves vertically, the battery is required to discharge at a large current for a certain period of time. In other words, the battery discharge load fluctuates greatly during flight, and the battery voltage also fluctuates drastically. The disclosed monitoring device uses a threshold value set for each travel mode, so battery abnormalities can be detected early. This improves flight safety.

[0008] Another aspect of the disclosure is a method for manufacturing a semiconductor device comprising: A monitoring method executed by a processor for monitoring a battery on board an electric flying vehicle, the method comprising: Acquire battery voltage information during flight and information regarding the travel mode of the electric flying object; outputting a monitoring result when a predetermined condition regarding a battery abnormality is satisfied using the voltage information and a threshold value set for each travel mode; This includes:

[0009] When an electric flying object moves vertically, the battery is required to discharge at a large current for a certain period of time. In other words, the battery discharge load fluctuates greatly during flight, and the battery voltage also fluctuates drastically. According to the disclosed monitoring method, a threshold value set for each movement mode is used, so that battery abnormalities can be detected early. This improves flight safety.

[0010] Another aspect of the disclosure is a method for manufacturing a semiconductor device comprising: A program stored in a storage medium (203) for monitoring a battery (14) installed in an electric flying object (10), the program including instructions to be executed by a processor (201), Acquiring battery voltage information during flight and information regarding the travel mode of the electric flying object; outputting a monitoring result when a predetermined condition regarding a battery abnormality is satisfied using the voltage information and a threshold value set for each travel mode; The instruction to execute the command is included.

[0011] When an electric flying object moves vertically, the battery is required to discharge at a large current for a certain period of time. In other words, the battery discharge load fluctuates greatly during flight, and the battery voltage also fluctuates greatly. According to the disclosed program, a threshold value set for each movement mode is used, so battery abnormalities can be detected early. This improves flight safety.

[0012] The various aspects disclosed in this specification adopt different technical means to achieve their respective objectives. The claims and the parenthetical symbols described in this section are merely illustrative of the corresponding relationship with the embodiments described below, and are not intended to limit the technical scope. The objectives, features, and effects disclosed in this specification will become clearer with reference to the following detailed description and the accompanying drawings. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing the configuration of an eVTOL and a ground station. [Diagram 2] FIG. 2 is a diagram showing the functional layout of the traffic management system. [Diagram 3] FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] FIG. 2 is a diagram showing a battery cell. [Figure 6] FIG. 2 illustrates a power profile. [Figure 7] FIG. 13 is a diagram illustrating detection of anomalies when fixed values ​​are used. [Figure 8] FIG. 1 illustrates an example of a monitoring device. [Figure 9] FIG. 13 is a diagram illustrating another example of a monitoring device. [Figure 10] FIG. 13 is a diagram illustrating an example of threshold values ​​stored in a memory. [Figure 11] FIG. 11 is a diagram illustrating an example of a threshold value set by a setting unit. [Figure 12] FIG. 13 is a diagram illustrating another example of the threshold value set by the setting unit. [Figure 13] FIG. 4 is a diagram showing a battery pack voltage Vb and a cell voltage Vc. [Figure 14] FIG. 13 is a diagram illustrating an example of threshold setting when a voltage change rate is used. [Figure 15] FIG. 13 is a diagram showing an example of threshold setting in the case where the variation in cell voltage is used; [Figure 16] 10 is a flowchart illustrating an example of a control method. [Figure 17] 10 is a flowchart showing another example of a control method. [Figure 18] FIG. 13 is a diagram showing a delay in the fluctuation of the battery voltage due to a normal transient response of the battery voltage. [Figure 19] FIG. 13 is a diagram showing the divergence of the voltage change rate accompanying a normal rapid change in battery voltage. [Figure 20] 10 is a flowchart showing another example of a control method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, several embodiments will be described with reference to the drawings. In addition, by assigning the same reference numerals to corresponding components in each embodiment, duplicated explanations may be omitted. When only a part of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other parts of the configuration. In addition to the combination of configurations explicitly stated in the description of each embodiment, configurations of several embodiments can be partially combined together even if not explicitly stated, as long as there is no particular problem with the combination.

[0015] The monitoring device, monitoring method, and program described below are applied to an electric flying object. Note that the description of A and / or B means at least one of A and B. In other words, it may include only A, only B, or both A and B.

[0016] (First embodiment) An electric flying body has a motor (rotating electric machine) as a drive source for movement. An electric flying body is sometimes called an electric airplane, an electric aircraft, etc. An electric flying body is capable of moving in the vertical direction and the horizontal direction. An electric flying body is capable of moving in a direction having a vertical component and a horizontal component, that is, in a diagonal direction. Examples of electric flying bodies include electric vertical take-off and landing aircraft (eVTOL), electric short take-off and landing aircraft (eSTOL), and drones. eVTOL is an abbreviation for electronic Vertical Take-Off and Landing aircraft. eSTOL is an abbreviation for electronic Short distance Take-Off and Landing aircraft.

[0017] The electric air vehicle may be either a manned or unmanned aircraft. In the case of a manned aircraft, the electric air vehicle is operated by a pilot as a pilot. In the case of an unmanned aircraft, the electric air vehicle may be operated by a remote control by a pilot, or may be automatically controlled by a control system. As an example, the electric air vehicle of this embodiment is an eVTOL.

[0018] <evtol> 1 shows an eVTOL and a ground station. As shown in FIG. 1, the eVTOL 10 includes an airframe 11, a fixed wing 12, a rotor 13, a battery 14, an EPU 15, and a BMS 16.

[0019] The aircraft body 11 is the fuselage of the aircraft. The aircraft body 11 has a shape that extends in the front-rear direction. The aircraft body 11 has a passenger compartment for passengers to ride in and / or a luggage compartment for carrying luggage.

[0020] The fixed wing 12 is a wing portion of the aircraft, and is connected to the aircraft body 11. The fixed wing 12 provides gliding lift. The gliding lift is the lift generated by the fixed wing 12. The fixed wing 12 may have a main wing 121 and a tail 122. The main wing 121 extends left and right from near the center in the fore-and-aft direction of the aircraft body 11. The tail 122 extends left and right from the rear of the aircraft body 11. The shape of the fixed wing 12 is not particularly limited. For example, a swept back wing, a delta wing, a straight wing, etc. may be adopted.

[0021] A plurality of rotors 13 are provided on the aircraft body. At least some of the plurality of rotors 13 may be provided on the fixed wing 12. At least some of the plurality of rotors 13 may be provided on the aircraft body 11. The number of rotors 13 provided on the eVTOL 10 is not particularly limited. A plurality of rotors 13 may be provided on each of the aircraft body 11 and the main wing 121.

[0022] The rotor 13 may be referred to as a rotor, a propeller, a fan, or the like. The rotor 13 may have blades 131 and a shaft 132. The blades 131 are attached to the shaft 132. The blades 131 are vanes that rotate together with the shaft 132. A plurality of the blades 131 extend radially around the axis of the shaft 132. The shaft 132 is a rotation axis of the rotor 13, and is rotated by a motor of the EPU 15.

[0023] The rotor 13 generates a thrust force by rotation. The thrust force acts on the eVTOL 10 mainly as a rotational lift during takeoff and landing operations of the eVTOL 10. The rotor 13 mainly provides rotational lift during takeoff and landing operations. The rotational lift is a lift force generated by the rotation of the rotor 13. During takeoff and landing operations, the rotor 13 may provide only the rotational lift, or may provide a forward thrust force in addition to the rotational lift. The rotor 13 provides rotational lift during hovering of the eVTOL 10.

[0024] The propulsive force acts primarily as thrust on the eVTOL 10 during cruising operation of the eVTOL 10. The rotor 13 primarily provides thrust during cruising operation. During cruising operation, the rotor 13 may provide only thrust or may provide lift in addition to thrust.

[0025] The battery (BAT) 14 is a device for driving the rotor 13 to rotate. The battery 14 may be referred to as a battery pack. The battery 14 can store DC power and has a rechargeable battery cell. The battery 14 has at least one assembled battery including a plurality of battery cells. The battery cell is a secondary battery that generates an electromotive force by a chemical reaction. The battery cell may be, for example, a lithium ion secondary battery or a nickel-metal hydride secondary battery. The battery cell may be a secondary battery with a liquid electrolyte or a so-called all-solid-state battery with a solid electrolyte. The battery cell may be configured such that a battery reaction occurs when ions (electrolyte) that contribute to the battery reaction move between the positive and negative electrodes via an electrolytic solution and / or a solid electrolyte. The eVTOL 10 may include, in addition to the battery 14, a fuel cell, a generator, or the like as a power source that supplies power to the devices. The battery 14 supplies power to the EPU 15. The battery 14 may supply power to auxiliary equipment (not shown) such as an air conditioner, an ECU 20 (described later), a lift adjustment mechanism (not shown), and the like.

[0026] The battery 14 of the eVTOL 10 is required to have high capacity as well as high output performance. For this reason, a battery cell that can obtain both high capacity and high output is desirable. From the viewpoint of output, a battery cell with low resistance over a wide SOC range is desirable. In particular, a battery cell with low resistance even in the low SOC range and capable of obtaining high output is desirable. SOC is an abbreviation for State Of Charge.

[0027] The positive electrode material of the battery cell can be, for example, LCO, NMC, NCA, LFP, or LMFP. LCO is lithium cobalt oxide (LiCoO2). NMC is lithium nickel cobalt manganese oxide (Li(NiMnCo)O2). NCA is lithium nickel cobalt aluminate (Li(NiCoAl)O2). LFP is lithium iron phosphate (LiFePO4). LMFP is lithium manganese iron phosphate (LiFe x Mn y PO4). LCO, NMC, and NCA are layered compounds. In particular, LMFP positive electrodes, which have low resistance in the low SOC region, or positive electrodes made by blending LMFP and NMC are preferred.

[0028] The negative electrode material of the battery cell can be, for example, carbon-based such as hard carbon or soft carbon, silicon, lithium-based, or titanium-based such as LTO or NTO. LTO is a lithium titanate (Li4Ti5O 12 ) NTO is niobium titanium oxide (TiNb2O7). In particular, carbon-based and titanium-based anodes, which have low resistance in the low SOC region, are preferred.

[0029] The EPU 15 drives and rotates the rotor 13 that imparts a propulsive force to the eVTOL 10. The EPU 15 is a device for driving and rotating the rotor 13. EPU is an abbreviation for Electric Propulsion Unit. The EPU 15 corresponds to an electric propulsion device. The EPU 15 includes a motor. The EPU 15 may include an inverter and an ESC in addition to the motor. ESC is an abbreviation for Electronic Speed ​​Controller. The number of EPUs 15 may be the same as the number of rotors 13. For example, the eVTOL 10 may include six EPUs 15. The EPUs 15 and the rotors 13 are connected one-to-one. Alternatively, a configuration may be adopted in which two or more rotors 13 are connected to one EPU 15 via a gear box.

[0030] The BMS 16 monitors the status of the unit batteries that make up the battery 14. BMS is an abbreviation for Battery Management System. The BMS 16 can monitor the voltage, current, temperature, internal resistance, SOC, SOH, and other safety-related statuses of the battery 14, such as internal pressure and gas leakage. SOH is an abbreviation for State Of Health. The BMS 16 may be provided integrally with the battery 14. The BMS 16 may be provided separately from the battery 14. A part of the BMS 16 may be provided inside the battery 14, and another part may be provided outside the battery 14.

[0031] The BMS 16 may be provided individually for each assembled battery. One BMS 16 may be provided for multiple assembled batteries. One BMS 16 may be provided for all assembled batteries. When multiple BMSs 16 are provided, a function for controlling all the BMSs 16 may be provided separately from the BMS 16, or may be provided integrally with the BMS 16.

[0032] The eVTOL 10 further includes an ECU 20 and auxiliary equipment (not shown). ECU is an abbreviation for Electronic Control Unit. The eVTOL 10 may include a lift adjustment mechanism (not shown). The lift adjustment mechanism adjusts the gliding lift of the fixed wing 12. The lift adjustment mechanism increases or decreases the gliding lift generated by the fixed wing 12. The eVTOL 10 may include, for example, a tilt mechanism or a flap as the lift adjustment mechanism. The tilt mechanism is driven to adjust the tilt angle of the rotor 13. The flap is a movable wing piece and is provided on the fixed wing 12.

[0033] <Traffic Traffic Management System> The traffic management system is a system for formulating flight plans, monitoring flight status, collecting and managing information related to flight operations, and supporting flight operations. At least some of the functions of the traffic management system may be arranged in an on-board computer of the eVTOL 10. At least some of the functions of the traffic management system may be arranged in an external computer capable of wireless communication with the eVTOL 10. The external computer may be a server 31 of a ground station 30 as shown in FIG. 1. The ground station 30 is capable of wireless communication with the eVTOL 10. The ground stations 30 are capable of wireless communication with each other.

[0034] As an example, in this embodiment, some of the functions of the traffic management system are arranged in the ECU 20 of the eVTOL 10, and some of the functions of the traffic management system are arranged in the server 31 of the ground station 30. The functions of the traffic management system are shared between the ECU 20 and the server 31.

[0035] As shown in FIG. 1, the ECU 20 includes a processor (PC) 201, a memory (MM) 202, a storage (ST) 203, and a communication circuit (CC) 204 for wireless communication. The processor 201 executes various processes by accessing the memory 202. The memory 202 is a rewritable volatile storage medium. The memory 202 is, for example, a RAM. RAM is an abbreviation for Random Access Memory. The storage 203 is a rewritable non-volatile storage medium. The storage 203 stores a program (PG) 203P to be executed by the processor 201. The program 203P configures a plurality of functional units by causing the processor 201 to execute a plurality of instructions. The ECU 20 may include a plurality of processors 201.

[0036] Like the ECU 20, the server 31 is configured to include a processor (PC) 311, a memory (MM) 312, a storage (ST) 313, a communication circuit (CC) 314, and the like. The processor 311 executes various processes by accessing the memory 312. The memory 312 is a rewritable volatile storage medium, such as a RAM. The storage 313 is a rewritable non-volatile storage medium. The storage 313 stores a program (PG) 313P to be executed by the processor 311. The program 313P configures a plurality of functional units by causing the processor 311 to execute a plurality of instructions. The server 31 may include a plurality of processors 311.

[0037] FIG. 2 shows an example of the functional arrangement of the traffic management system. The traffic management system 40 shown in FIG. 2 has an external management unit 41 and an internal management unit 42. The external management unit 41 is functionally arranged in the server 31 of the ground station 30. The internal management unit 42 is functionally arranged in the ECU 20 of the eVTOL 10. In this way, some of the functions of the traffic management system 40 may be arranged in the server 31, and other parts of the functions may be arranged in the ECU 20. The external management unit 41 and the internal management unit 42 can wirelessly communicate with each other. The internal management unit 42 can communicate with various devices arranged in the eVTOL 10 via wired or wireless communication.

[0038] <Battery> FIG. 3 shows an example of a battery 14. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 3. FIG. 4 shows a simplified configuration of a battery cell. FIG. 5 is a diagram showing the arrangement of electrode terminals. In the following, the height direction of each battery cell is referred to as the Z direction, a direction perpendicular to the Z direction is referred to as the Y direction, and a direction perpendicular to both the Z direction and the Y direction is referred to as the X direction. For convenience, the entire battery cell is shown in FIG. 4 with metallic hatching.

[0039] As shown in Figures 3 and 4, the battery 14 includes at least one assembled battery 141. The assembled battery 141 includes a plurality of battery cells 142. The plurality of battery cells 142 may have a common structure, or some of the battery cells 142 may have a different structure from the others. The number and arrangement of the plurality of battery cells 142 are not particularly limited. The plurality of battery cells 142 may be connected in series, or may be connected in parallel and in series.

[0040] The battery cell 142 has a power generating element and a battery case that houses the power generating element. The battery case provides the outer shell of the battery cell 142. The battery case may be formed, for example, using a metal material or a laminate film. The shape of the battery cell 142, i.e., the battery case, is not particularly limited. It may be a rectangular shape, a laminate type, or a cylindrical shape.

[0041] Each battery cell 142 has electrode terminals 142P, 142N. As shown in FIG. 5, the electrode terminals 142P, 142N may be provided on a common surface or on different surfaces. For example, they may be provided on one surface and the surface opposite to the one surface. The electrode terminals 142P, 142N may protrude from the corresponding surface. The electrode terminal 142P is electrically connected to the positive electrode of the battery cell 142. The electrode terminal 142P may be referred to as a positive electrode terminal, a P terminal, or the like. The electrode terminal 142N is electrically connected to the negative electrode of the battery cell 142. The electrode terminal 142N may be referred to as a negative electrode terminal, an N terminal, or the like. The electrode terminals may be referred to as a battery cell terminal, a current collecting tab, or the like.

[0042] The battery cell 142 shown in Figures 3 and 4 has a rectangular shape, specifically a flat shape that is thin in the Y direction. The multiple battery cells 142 are arranged side by side in the Y direction. The electrode terminals 142P, 142N are provided on one of the end faces in the Z direction, i.e., on a common surface. The multiple battery cells 142 are arranged such that the electrode terminals 142P and the electrode terminals 142N are positioned alternately in the Y direction. In adjacent battery cells 142, the electrode terminals 142P and the electrode terminals 142N are electrically connected by a bus bar (not shown).

[0043] The battery pack 141 may include a plurality of battery cells 142 arranged in the Y direction. The arrangement of the battery cells 142 is not limited to the above arrangement. For example, in the case of cylindrical battery cells 142, they may be arranged in a staggered pattern when viewed from the Z direction.

[0044] <Power Profile> FIG. 6 shows the power profile of the eVTOL10 from takeoff to landing. The power profile of electric flying objects other than the eVTOL10 is the same as that of the eVTOL10. The period P1 is referred to as takeoff, takeoff flight, takeoff operation, etc. The period P2 is referred to as cruising, cruising flight, cruising operation, etc. The period P3 is referred to as landing, landing flight, landing operation, etc. The periods P1 and P3 are referred to as takeoff and landing, takeoff and landing flight, takeoff and landing operation, etc. For convenience, the required power, that is, the output, is constant throughout almost the entire range of each of the periods P1 and P3 in FIG. 6.

[0045] The eVTOL 10 ascends from the takeoff point to the cruise start point in period P1. The eVTOL 10 cruises at a predetermined altitude in period P2. The eVTOL 10 descends from the end point of period P2 to the landing point in period P3. The movement of the eVTOL 10 includes mainly horizontal components in period P2 and mainly vertical components in periods P1 and P3. In periods P1 and P3 during vertical movement, high output is required continuously for a predetermined period of time to drive the rotor 13.

[0046] Thus, a high output load is applied to the battery 14 during vertical movement. The largest output is required during takeoff and landing. The output of the battery 14 varies greatly between vertical movement and horizontal movement. The output of the battery 14 varies greatly between takeoff and landing and cruising.

[0047] <Battery voltage> Fig. 7 is a diagram showing anomaly detection when a fixed threshold is used, in which the change in battery voltage during flight is shown by a solid line.

[0048] As described above, during vertical movement, particularly during takeoff and landing, the battery 14 that drives the EPU 15 is required to discharge at a large current for a certain period of time. For example, during takeoff and landing, the battery 14 continuously discharges at a maximum discharge rate of about 3C to about 15C for about 30 seconds to about 90 seconds.

[0049] The discharge rate indicates the relative ratio of the current during discharge to the battery capacity, and is expressed in units of C. A discharge rate of 1C indicates the current value at which a cell with a nominal capacity is discharged at a constant current and the discharge is completed in one hour. The maximum discharge rate during cruising of an electric aircraft or an electric vehicle (BEV) is about 1C to 2C. In the case of a BEV, this is a level at which the maximum discharge rate continues for about 5 to 10 seconds. BEV is an abbreviation for Battery Electric Vehicle. As such, there is a large variation in the discharge characteristics between takeoff and landing and cruising.

[0050] Monitoring the battery voltage, which is sensitive to internal short circuits and rapid deterioration that can cause thermal runaway in the battery 14, is used as a means of early detection of abnormalities. However, during flight, the discharge load of the battery 14 fluctuates greatly, and the battery voltage also fluctuates greatly, as shown by the solid line in Figure 7. For this reason, it is difficult to detect abnormalities early using management that uses a fixed value (constant value) as the threshold value.

[0051] For example, if an abnormality occurs at time t1 during cruising and the voltage drops as shown by the dashed arrow, the abnormality can be detected at time t2 by using a relatively high fixed value 1. Although the abnormality can be detected early in this way, erroneous determinations will occur at takeoff and landing because the value of fixed value 1 is high. On the other hand, erroneous determinations at takeoff and landing can be avoided by using fixed value 2 that is lower than fixed value 1 and higher than the lower limit of tolerance of battery 14. However, the abnormality will be detected at time t3, which is later than time t2. In other words, the abnormality cannot be detected early.

[0052] <Monitoring device> Fig. 8 shows an example of a monitoring device. Fig. 9 shows another example of a monitoring device. As shown in Fig. 8, the monitoring device 50 may include an acquisition unit 51, a determination unit 52, and an output unit 53. As shown in Fig. 9, the monitoring device 50 may further include a setting unit 54.

[0053] The monitoring device 50 monitors the battery 14. The functional arrangement of the monitoring device 50 is not particularly limited. At least a part of the functions of the monitoring device 50 may be arranged on-board or off-board. The functions of the monitoring device 50 may be distributed across multiple devices on-board. The functions of the monitoring device 50 may be distributed across multiple devices off-board. Some of the functions of the monitoring device 50 may be arranged on-board and another part of the functions may be arranged off-board.

[0054] For example, at least a part of the functions of the monitoring device 50 may be arranged in the BMS 16. At least a part of the functions of the monitoring device 50 may be arranged in the ECU 20. At least a part of the functions of the monitoring device 50 may be arranged in the server 31 of the ground station 30. At least a part of the functions of the monitoring device 50 may be arranged in the traffic management system 40. At least a part of the functions of the monitoring device 50 may be arranged in the on-board management unit 42. At least a part of the functions of the monitoring device 50 may be arranged in the off-board management unit 41.

[0055] The acquisition unit 51 acquires information related to the voltage of the battery 14 during flight and information related to the travel mode of the eVTOL 10. Information related to the voltage of the battery 14 during flight may be referred to as battery voltage information or voltage information. Information related to the travel mode may be referred to as travel mode information.

[0056] The acquisition unit 51 may acquire information such as voltage information and travel mode information from the BMS 16, the traffic management system 40, the EPU 15, etc. The acquisition unit 51 may acquire actual measured values, intermediate calculated values, or calculated values ​​such as feature quantities as information. The information may be acquired by performing calculations within the monitoring device 50 based on the actual measured values ​​and intermediate calculated values ​​acquired from the BMS 16, etc. The acquisition unit 51 acquires information through wireless communication and / or wired communication.

[0057] For example, the resistance of the battery 14 changes depending on the environmental temperature. The battery voltage is affected by the fluctuation in the battery resistance. In other words, the battery voltage is affected by the environmental temperature, etc. Therefore, the acquisition unit 51 may acquire environmental information in addition to the voltage information and the travel mode information. As the environmental information, for example, the temperature, wind speed, wind direction, etc. may be acquired. Taking into account the fluctuation in the environmental parameters, the accuracy of the abnormality determination can be improved.

[0058] The eVTOL10 may take multiple movement modes during flight. The movement modes may include a mode of moving mainly in a vertical direction and a mode of moving mainly in a horizontal direction. In addition to the mode of moving vertically and the mode of moving horizontally, a mode of moving in a diagonal direction may be included. The eVTOL10 moves mainly in a vertical direction during takeoff and landing, and mainly in a horizontal direction during cruising. Thus, the movement modes may include a takeoff and landing mode and a cruising mode. The movement modes may include a takeoff mode, a cruising mode, and a landing mode. The cruising mode may be subdivided in consideration of a case where the vehicle temporarily moves vertically during cruising.

[0059] The acquisition unit 51 may acquire information indicating the travel mode itself as the travel mode information, or may acquire information for determining the travel mode. The acquisition unit 51 may acquire discharge characteristic information and / or flight information as the travel mode information. The acquisition unit 51 may have a function of determining the travel mode based on the acquired discharge characteristic information and / or flight information. The monitoring device 50 may include a functional unit that determines the travel mode based on the information acquired by the acquisition unit 51, separate from the acquisition unit 51. The discharge characteristic information is information related to the discharge current. For example, if the discharge current is equal to or greater than a predetermined threshold, it may be determined to be a vertical travel mode, and if it is less than the threshold, it may be determined to be a horizontal travel mode.

[0060] The flight information may be a signal indicating a travel mode obtained from the traffic management system 40 or the like. The flight information may be altitude change information such as the ascent speed and descent speed of the eVTOL 10. For example, if the ascent speed is equal to or greater than a predetermined threshold, it may be determined to be a vertical travel mode, and if it is less than the threshold, it may be determined to be a horizontal travel mode. The flight information may be information indicating the orientation of the rotor 13. In the case of a configuration in which the orientation of the rotor 13 can be changed according to the travel mode by a tilt mechanism or the like, the travel mode can be determined by information on the orientation of the rotor 13. The flight information may be time information in the flight. If the operation is accurately time-managed, the travel mode may be determined by time. In the case of repeated movement between spots, the operation is accurately time-managed. In particular, in the case of automatic operation, the operation is more accurately time-managed.

[0061] The acquisition unit 51 may acquire information on the battery state together with the discharge characteristic information as the travel mode information. The battery state information is an open circuit voltage (OCV) and / or a resistance. OCV is an abbreviation for Open Circuit Voltage. Instead of OCV, SOC may be acquired. SOC is an abbreviation for State Of Charge.

[0062] The determination unit 52 has a function of comparing the voltage information acquired by the acquisition unit 51 with a threshold value set for each travel mode to determine the presence or absence of a battery abnormality. The threshold value may be set to a different value for each travel mode. The determination unit 52 functions as a detection unit that detects a battery abnormality. The determination unit 52 may have a function of determining whether or not the detection of an abnormality is performed normally based on the voltage information. The determination unit 52 may function as a diagnosis unit that diagnoses (determines) whether or not the abnormality detection function is normal. The monitoring device 50 may include a diagnosis unit separate from the determination unit 52. The monitoring device 50 may include a diagnosis unit separate from the detection unit. The determination unit 52 may have a function of limiting the abnormality detection and the threshold value for a predetermined period. The determination unit 52 may function as a limiting unit that limits the abnormality detection and the threshold value. The monitoring device 50 may include a limiting unit separate from the determination unit 52 (detection unit).

[0063] The output unit 53 outputs the abnormality determination result to the outside of the monitoring device 50. The output unit 53 outputs the monitoring result when a predetermined condition regarding an abnormality in the battery 14 is satisfied. The output unit 53 may output the determination result, for example, to issue an alarm to the crew or the ground station 30. The output unit 53 may output the determination result to trigger a transition to an avoidance operation. The output unit 53 may output the determination result to the traffic management system 40 that displays the operational status of the aircraft and controls the operation. The monitoring device 50 itself may display the result. The output unit 53 may output a control request for an avoidance operation to a control device that controls flight. The control device may be provided integrally as one function of the traffic management system 40, or may be provided separately.

[0064] The output unit 53 may output in multiple stages, such as an alarm in the first stage and an avoidance operation in the second stage and thereafter. As the avoidance operation, for example, a redundant operation of the battery 14 may be adopted, or an emergency landing operation may be adopted. The redundant operation of the battery 14 may be, for example, stopping the output of the system with an abnormality and continuing the flight with the remaining system. As the avoidance operation, a plurality of operations may be executed simultaneously. The avoidance operation may be capable of being performed in stages. The output unit 53 may estimate the time until an abnormality occurs based on the time series transition of the target information, and output it as urgency information.

[0065] The setting unit 54 sets a threshold value for comparison with the voltage information based on the travel mode information acquired by the acquisition unit 51. The setting unit 54 sets a threshold value for each travel mode. The setting unit 54 may set the threshold value to a different value for each travel mode. The setting unit 54 may set the threshold value based on the discharge characteristic information and battery state information, which are the travel mode information.

[0066] <Threshold> The threshold is set individually for each travel mode. The threshold is set according to the travel mode. The threshold may be associated with the relationship with the travel mode and stored in advance in the memory. The determination unit 52 reads out the threshold corresponding to the travel mode from the memory and uses it for determination. FIG. 10 shows an example of the threshold stored in the memory. The travel mode includes two types, a takeoff / landing mode and a cruising mode. The memory stores a threshold Th1 corresponding to the takeoff / landing mode and a threshold Th2 corresponding to the cruising mode. The determination unit 52 makes a determination using the threshold Th1 in the takeoff / landing mode, and makes a determination using the threshold Th2 in the cruising mode. The threshold Th1 is set to a value lower than the threshold Th2 and higher than the allowable lower limit.

[0067] The threshold value may be set by deriving normal voltage behavior during flight using, for example, prior experiments or battery simulations, and allowing a certain margin for the voltage behavior. The margin is, for example, a margin for variations in battery discharge characteristics, fluctuations in OCV or battery resistance, errors in the detection system, etc. Threshold values ​​may be prepared for each flight plan, such as for differences in flight routes.

[0068] The threshold may be set by the setting unit 54 according to the travel mode. The setting unit 54 may set the threshold based on the discharge characteristic information and the battery state information acquired by the acquisition unit 51. FIG. 11 shows an example of the threshold set by the setting unit 54. FIG. 12 shows another example of the threshold set by the setting unit 54. In FIG. 11 and FIG. 12, the travel mode includes three types of a takeoff mode, a cruising mode, and a landing mode. The setting unit 54 sets a threshold Th11 corresponding to the takeoff mode, a threshold Th12 corresponding to the cruising mode, and a threshold Th13 corresponding to the landing mode.

[0069] The relationship between the battery voltage during discharge, the discharge characteristics (discharge current), and the battery state (OCV, battery resistance) is as shown in Equation 1. Therefore, if the discharge characteristics information and the battery state are reflected in the threshold setting, it becomes possible to detect abnormalities earlier and with higher accuracy. Battery voltage during discharge = OCV - discharge current × battery resistance (Equation 1) The OCV decreases with a decrease in the SOC. It is advisable to create an SOC-OCV map in advance and calculate the OCV from the SOC value. The SOC decreases during landing compared to takeoff. For this reason, as shown in FIG. 11, it is advisable to set the threshold value Th13 set during landing lower than the threshold value Th11 set during takeoff.

[0070] The resistance of the battery 14 also changes with the SOC. The behavior of the resistance may be obtained in advance by an experiment or the like, and may be calculated using a map model or a regression model. Many of the battery cells 142 tend to have increased resistance in the low SOC region. The setting unit 54 may reflect the resistance in the threshold setting, particularly in flights using the low SOC region.

[0071] The setting unit 54 may set the threshold value using information updated before flight by a battery status diagnosis performed when the aircraft is parked between flights. The battery status diagnosis may include an AC impedance diagnosis. Parameters of a battery equivalent circuit model and a battery reaction model, such as DC resistance, battery reaction resistance, and diffusion resistance, may be obtained. This allows the voltage fluctuation during discharge (during flight) to be simulated immediately before flight, resulting in higher accuracy.

[0072] The setting unit 54 may sequentially change the set threshold value based on a change in the battery state during flight. As shown in FIG. 12, the setting unit 54 may sequentially change the threshold value in accordance with a change in the battery voltage. This enables earlier and more accurate detection of anomalies. The setting unit 54 may set the threshold value based on a flight plan at the time of flight planning. The setting unit 54 may set the threshold value according to the performance during flight. The threshold value based on the plan may be updated according to the performance.

[0073] The setting unit 54 may use, as the battery state information, information on an increase in resistance caused by a concentration bias of ions that contribute to the battery reaction. When the battery 14 is discharged, a temporary bias occurs in the concentration distribution of ions that contribute to the battery reaction. The concentration bias occurs in the electrolyte or electrodes. When the concentration bias occurs, the internal resistance of the battery 14 increases temporarily (reversibly). Therefore, even if the SOC of the battery 14 is sufficient, the output performance of the battery 14 decreases. In this way, temporary (reversible) deterioration occurs in the battery 14. The temporary deterioration is sometimes called high-rate deterioration.

[0074] The greater the concentration bias, the greater the degree of temporary deterioration. Electric flying objects, particularly the eVTOL 10, require high output during takeoff and landing. In addition, continuous output is required during flight. Therefore, the degree of temporary deterioration is likely to increase. The setting unit 54 predicts the degree of temporary deterioration and reflects it in the threshold value, thereby enabling earlier and more accurate abnormality detection. The setting unit 54 may predict primary deterioration in advance and reflect it in the threshold value.

[0075] The setting unit 54 may acquire information on the degree of temporary deterioration of the battery 14, or may calculate the degree of temporary deterioration based on the acquired information. The degree of temporary deterioration is a difference from a reference value of the internal resistance. The reference value may be, for example, the initial internal resistance value before takeoff in the current flight. The reference value may be the value of the internal resistance after a process for eliminating temporary deterioration, or the value of the internal resistance after charging on the ground. The reference value is preferably the value of the internal resistance after temporary deterioration has been sufficiently eliminated. The calculation of the degree of temporary deterioration may be an actual measurement calculation based on an actual measurement value, or a predictive calculation based on a predictive value. The calculated value may be the degree of temporary deterioration at the time of monitoring, or the degree of temporary deterioration at the time of takeoff or landing.

[0076] The setting unit 54 may predict the degree of primary deterioration in advance and reflect it in the threshold value. The setting unit 54 may predict the degree of primary deterioration in advance by calculating a fluctuation profile of primary deterioration based on a discharge profile planned for the flight. The setting unit 54 may predict the degree of primary deterioration based on, for example, a prediction map or a prediction model such as multiple regression. The degree of primary deterioration may be predicted based on a prediction model generated using machine learning.

[0077] The setting unit 54 may predict the degree of temporary deterioration in advance by calculating a fluctuation profile of temporary deterioration using past history data. The history data may be information on the degree of past temporary deterioration in which the takeoff point and / or landing point and the model match the target flight. The flight plan of the eVTOL10 is finite and is repeated frequently, so history information can be used. Furthermore, since history information on the takeoff point and landing point, which are prone to prediction errors, is used, the prediction accuracy of the degree of temporary deterioration can be improved. The ease of operation, output characteristics, etc. differ depending on the model (type) of the eVTOL10. This can further improve the prediction accuracy of the degree of temporary deterioration.

[0078] The setting unit 54 may set the threshold value according to the degree of increase (performance) of temporary deterioration during flight. The setting unit 54 may update the prediction-based threshold value according to performance. The setting unit 54 may calculate the degree of temporary deterioration based on the output history of the battery. The setting unit 54 may calculate the integrated value of the discharge current during flight as the degree of temporary deterioration. When charging is performed, the integrated value of the charge / discharge current may be used as the degree of temporary deterioration. Output stop during standby on the ground and temporary output stop during flight also act to eliminate the concentration bias caused by discharge to some extent. Therefore, the current integrated value may be corrected in the direction of eliminating the concentration bias.

[0079] In addition, the larger the current (higher output) or the longer the duration of the output, the more likely the concentration bias is to occur. Therefore, when using the integrated current value, the current value and / or duration may be weighted during integration. The weighting coefficient may be calculated using a map or regression model created in advance from experimental data, etc.

[0080] The setting unit 54 may calculate the degree of temporary deterioration using a battery physics model. The battery physics model is a model that models electrochemical reactions and material transport and is capable of analyzing concentration distribution. By inputting a current history into this battery physics model and performing calculations, it is possible to estimate the concentration bias of ions in the electrolyte and electrodes that contribute to the battery reaction.

[0081] The setting unit 54 may calculate the degree of temporary degradation based on the battery resistance. The setting unit 54 may calculate the amount of increase (amount of change) in the internal resistance, that is, the degree of temporary degradation itself. The amount of change becomes an amount of decrease when the temporary degradation is eliminated. The amount of increase in resistance of the battery 14 can be calculated using the time series values ​​of the internal resistance calculated from the voltage, current, etc. of the battery 14.

[0082] The setting unit 54 may calculate the degree of temporary deterioration using an estimated resistance based on a battery model. The battery model is, for example, a battery equivalent circuit model. The estimated resistance is calculated from an estimated current estimated from a battery model that assumes a uniform concentration distribution, and an actually measured voltage. The degree of temporary deterioration can be calculated from the difference between the estimated resistance and a measured resistance calculated from the actually measured current and voltage.

[0083] The setting unit 54 may calculate the degree of temporary deterioration based on the resistance component of the AC impedance. The increase (change) in the resistance component of the AC impedance of the battery 14 can be used as the degree of temporary deterioration. In particular, the increase in the resistance component in the high frequency range of the AC impedance can be used as the degree of temporary deterioration. The degree of concentration bias in the electrolyte, which is the main cause of bias, can be calculated more accurately.

[0084] The setting unit 54 may calculate the degree of temporary deterioration based on history information of past flights. As the history information, information on the degree of past temporary deterioration in which the takeoff point and / or landing point and the model match the target flight may be used. The flight plan of the eVTOL10 is finite and is repeated frequently, so that the history information can be utilized. Furthermore, since the history information of the takeoff point and landing point, which are prone to prediction errors, is utilized, the prediction accuracy of the degree of temporary deterioration can be improved. The ease of operation, output characteristics, etc. differ depending on the model (type) of the eVTOL10. This can further improve the prediction accuracy of the degree of temporary deterioration.

[0085] <Voltage information> Fig. 13 shows the battery pack voltage Vb and the cell voltage Vc. Fig. 14 shows an example of threshold setting when the voltage change rate is used. Fig. 15 shows an example of threshold setting when the cell voltage variation is used. In Fig. 14, the threshold for the takeoff and landing mode is set to Th21, and the threshold for the cruising mode is set to Th22. In Fig. 15, the threshold for the takeoff and landing mode is set to Th31, and the threshold for the cruising mode is set to Th32.

[0086] 7, when the voltage drops due to an abnormality in the battery 14, the absolute value decreases, the voltage change rate increases, and the variation between cells increases. The voltage change rate is sometimes called the voltage change speed.

[0087] The acquisition unit 51 may acquire, as the battery information, an absolute value of the assembled battery voltage Vb shown in Fig. 13. The acquisition unit 51 may acquire an absolute value of each cell voltage Vc. The acquisition unit 51 may acquire, as the battery information, a voltage change rate as shown in Fig. 14. The voltage change rate may be the change rate of the assembled battery voltage Vb or the change rate of the cell voltage Vc. The acquisition unit 51 may acquire, as the battery information, a variation in the cell voltage Vc as shown in Fig. 15.

[0088] The acquiring unit 51 may acquire at least one of the following battery information: absolute value of the assembled battery voltage Vb, absolute value of each cell voltage Vc, rate of change of the assembled battery voltage Vb, rate of change of the cell voltage Vc, and variation of the cell voltage Vc. By monitoring multiple parameters such as absolute value, rate of change, and variation, it becomes possible to detect an abnormality in the battery 14 with higher accuracy.

[0089] <Monitoring method> As described above, the monitoring device 50 may be disposed in the ECU 20 of the eVTOL 10. In this case, the execution of processing of each functional block of the monitoring device 50 by the processor 201 corresponds to the execution of the monitoring method. The monitoring device may be disposed in the server 31 of the ground station 30. In this case, the execution of processing of each functional block of the monitoring device 50 by the processor 311 corresponds to the execution of the monitoring method.

[0090] As a monitoring method, for example, the method shown in FIG. 16 may be used. The monitoring device 50 (for example, the processor 201) repeatedly executes the process shown in FIG. 16 at a predetermined cycle. First, the monitoring device 50 acquires information (step S10). The monitoring device 50 acquires travel mode information and voltage information of the battery 14. The monitoring device 50 may acquire the above-mentioned flight information as the travel mode information. The monitoring device 50 may acquire discharge characteristic information of the battery 14 as the travel mode information. The monitoring device 50 may acquire flight information and discharge characteristic information as the travel mode information. The monitoring device 50 may acquire discharge characteristic information and battery status information as the travel mode information. The monitoring device 50 may acquire flight information, discharge characteristic information, and battery status information as the travel mode information.

[0091] Next, the monitoring device 50 sets a threshold value for each travel mode individually (step S20). The monitoring device 50 may read a threshold value corresponding to the travel mode from a memory and set the threshold value. The monitoring device 50 may set the threshold value by calculation or the like based on the travel mode information. The monitoring device 50 may set the threshold value based on the discharge characteristic information and the battery state information.

[0092] Next, the monitoring device 50 compares the acquired voltage information with a threshold value and determines whether the voltage information is outside the allowable threshold range (step S30). For example, the monitoring device 50 may determine that the voltage information is outside the allowable threshold range when the absolute value of the assembled battery voltage Vb is less than the threshold value, and may determine that the voltage information is within the allowable threshold range when the absolute value of the assembled battery voltage Vb is equal to or greater than the threshold value. The monitoring device 50 may determine that the voltage information is outside the allowable threshold range when the absolute value of the assembled battery voltage Vc is less than the threshold value, and may determine that the voltage information is within the allowable threshold range when the absolute value of the assembled battery voltage Vc is equal to or greater than the threshold value. The monitoring device 50 may determine that the voltage information is outside the allowable threshold range when the rate of change of the assembled battery voltage Vb is greater than the threshold value, and may determine that the voltage information is within the allowable threshold range when the rate of change of the cell voltage Vc is greater than the threshold value, and may determine that the voltage information is within the allowable threshold range when the rate of change of the cell voltage Vc is less than the threshold value. The monitoring device 50 may determine that the voltage information is outside ... variation of the cell voltage Vc is greater than the threshold value, and may determine that the voltage information is within the allowable threshold range when the variation of the cell voltage Vc is less than the threshold value.

[0093] If the voltage information is outside the allowable threshold range, the monitoring device 50 determines that there is an abnormality in the battery 14, executes an output indicating that there is an abnormality (step S40), and ends the series of processes. If the voltage information is within the allowable threshold range, the monitoring device 50 does not execute the process of step S40 and ends the series of processes.

[0094] As a monitoring method, the method shown in Fig. 17 may be used. First, the monitoring device 50 executes the process of step S10, similar to the method shown in Fig. 16. Next, the monitoring device 50 determines whether or not it is outside of a predetermined period during transition (step S15). The monitoring device 50 determines whether or not it is outside of a predetermined period during transition between vertical movement and horizontal movement.

[0095] The equivalent circuit of the battery 14 includes a capacitor component connected in parallel to a resistor. Therefore, as shown in FIG. 18, the fluctuation in the battery voltage generates a transient response according to the capacitor component. For example, a transient response occurs when switching from takeoff to cruising. The battery voltage also fluctuates suddenly when transitioning (switching) between vertical movement and horizontal movement. Therefore, as shown in FIG. 19, divergence of the voltage change rate occurs during the transition. Furthermore, delays in signal propagation in the circuit may cause delays in switching the threshold.

[0096] In this way, when the movement is switched between the vertical direction and the horizontal direction, a normal sudden change in the voltage information, a delay in the change in the battery voltage due to a normal transient response, and a delay in switching the threshold value may occur, which may lead to erroneous determination.

[0097] In the example shown in FIG. 17, in order to prevent the above-mentioned erroneous judgment, it is judged whether or not the timing corresponds to a timing where the above-mentioned sudden fluctuation in voltage, delay in voltage fluctuation, and delay in threshold switching may occur, that is, a predetermined period during transition. The predetermined period is at least a part of the period during transition. The predetermined period may be set based on the derived periods, for example, by deriving the period of normal sudden fluctuation in voltage information during transition, the delay period of fluctuation in battery voltage due to normal transient response, and the delay period of threshold switching using a prior experiment or battery simulation. The predetermined period may also be set with a predetermined margin for the derived periods.

[0098] If it is determined in step S15 that the period is outside the predetermined period, the monitoring device 50 executes the processes from step S20 onwards, similar to the method shown in Fig. 16. On the other hand, if it is determined that the period is not outside the predetermined period, that is, that the period is within the predetermined period, the monitoring device 50, for example, restricts monitoring (step S21). The monitoring device 50 excludes the predetermined period from detecting anomalies. The monitoring device 50 does not detect anomalies based on voltage information for the predetermined period. The monitoring restriction can be applied to any of the above-mentioned sudden voltage fluctuations, delays in voltage fluctuations, and delays in threshold switching.

[0099] In step S21, the monitoring device 50 may execute a process of applying a threshold value before the transition instead of limiting the monitoring. For example, the threshold value set during vertical movement is maintained for a predetermined period during the transition from vertical movement to horizontal movement. The application of the threshold value before the transition can be applied to the above-mentioned voltage fluctuation delay and threshold switching delay. The monitoring device 50 may execute a process of applying an upper limit voltage or lower limit voltage allowed for the battery 14 as a threshold value instead of limiting the monitoring. The application of the allowed upper limit voltage or lower limit voltage can be applied to the above-mentioned voltage fluctuation delay and threshold switching delay. In this way, the threshold value may be limited to a predetermined value.

[0100] After executing the process of step S21, the monitoring device 50 executes the processes of step S30 and thereafter, similarly to the method shown in FIG.

[0101] As a monitoring method, the method shown in FIG. 20 may be used. First, the monitoring device 50 executes the processes of steps S10 and S20 in the same manner as the method shown in FIG. 16. Next, the monitoring device 50 judges whether or not the difference between the assembled battery voltage Vb and the sum of all the cell voltages Vc is equal to or less than a predetermined value (step S25). The monitoring device 50 diagnoses that the detection of anomalies is performed normally. The sum of all the cell voltages Vc is a value obtained by adding up the voltages (cell voltages Vc) of all the battery cells 142 in the assembled battery 141 that generate the assembled battery voltage Vb. The predetermined value may be set based on the difference between the normal assembled battery voltage Vb during flight and the sum of all the cell voltages Vc, for example, by using a prior experiment or a battery simulation. The predetermined value may be set with a predetermined margin for the derived difference.

[0102] If it is determined in step S25 that the difference is within the predetermined value, the monitoring device 50 executes the process from step S30 onwards, similar to the method shown in Fig. 16. On the other hand, if it is determined that the difference is not equal to or less than the predetermined value, that is, the difference is greater than the predetermined value, the monitoring device 50 executes an output indicating that there is a suspicion of a monitoring abnormality (step S41) and ends the series of processes. If the difference is not equal to or less than the predetermined value, the monitoring device 50 does not execute the processes of steps S30 and S40, that is, does not detect an abnormality, and ends the series of processes.

[0103] In the method shown in Fig. 16, if the battery information is within the allowable threshold range, the monitoring device 50 may output that there is no abnormality, and then end the series of processes. The same applies to the method shown in Fig. 17 and the method shown in Fig. 20.

[0104] The determination unit 52 (detection unit) of the monitoring device 50 may execute the process of step S15 and the process of step S21 shown in Fig. 17. A functional unit other than the determination unit 52 may execute at least one of the process of step S15 and the process of step S21.

[0105] <Summary of the First Embodiment> As described above, when the eVTOL 10 (electric flying vehicle) moves vertically, the battery 14 is required to discharge a large current for a certain period of time. Monitoring the battery voltage, which reacts sensitively to internal short circuits and rapid deterioration that can cause thermal runaway in the battery 14, is used as a means of early detection of anomalies. However, during flight, the discharge load of the battery 14 fluctuates greatly, and the battery voltage also fluctuates wildly. For this reason, it is difficult to detect anomalies early using management that uses a fixed value (constant value) as a threshold value.

[0106] According to the monitoring device 50 of this embodiment, information on the travel mode is obtained along with voltage information on the battery 14, and the voltage information is monitored using a threshold value set for each travel mode. This makes it possible to detect an abnormality in the battery 14 at an early stage, thereby improving flight safety.

[0107] The monitoring device 50 may be applied to a configuration in which the maximum discharge rate of the battery 14 during vertical movement of the eVTOL 10 is 1.5 times or more the maximum discharge rate during horizontal movement. The monitoring device 50 may be applied to a configuration in which the discharge rate during vertical movement is 3C or more.

[0108] As described above, electric flying objects such as the eVTOL 10 have a large variation in discharge characteristics. The greater the variation in discharge characteristics, the greater the effect of early detection by the monitoring device 50. For example, when the ratio of the maximum discharge rate during vertical movement to the maximum discharge rate during horizontal movement is 1.5 times or more, the effect of early detection is increased. When the ratio is even higher, for example, 2 times or more, 3 times or more, or 5 times or more, a greater effect can be achieved. The higher the discharge rate during vertical movement, the greater the effect of early detection by the monitoring device 50. When the discharge rate is 3C or more, the effect of early detection is increased. When the discharge rate is even higher, for example, 5C or more, 7C or more, or 10C or more, a greater effect can be achieved.

[0109] The monitoring device 50 may acquire battery discharge characteristic information and / or flight information as information related to the travel mode. By using this information, the threshold value can be switched at an appropriate timing according to the travel mode.

[0110] The monitoring device 50 sets a threshold value for each travel mode based on the discharge characteristic information and battery state information, which are information related to the travel mode. As shown in Equation 1, a predetermined relationship is established among the battery voltage, OCV, discharge current, and battery resistance during discharge. By reflecting the discharge characteristic information (discharge current) and battery state information (OCV, battery resistance), which affect the battery voltage, in the setting of the threshold value, it becomes possible to detect abnormalities earlier and with higher accuracy.

[0111] The monitoring device 50 may use information on the increase in resistance caused by the concentration bias of ions that contribute to the battery reaction to set the threshold value. This makes it possible to suppress false detection due to the increase in resistance caused by temporary deterioration and to increase the reliability of abnormality detection.

[0112] The monitoring device 50 may use battery status information updated before flight by a battery status diagnosis performed when the aircraft is parked. The battery status information is updated for each flight. Using battery status information updated for each flight can further improve the accuracy of detecting anomalies.

[0113] The monitoring device 50 may change the set threshold value successively based on changes in the battery state during flight. By successively changing the threshold value according to fluctuations in the battery voltage, it becomes possible to detect abnormalities more quickly and with higher accuracy.

[0114] The monitoring device 50 may obtain at least one of the following voltage information: absolute value of the assembled battery voltage Vb, absolute value of the cell voltage Vc, rate of change of the assembled battery voltage Vb, rate of change of the cell voltage Vc, and variation of the cell voltage Vc. By using the above parameters that respond sensitively to internal short circuits and rapid deterioration, abnormalities can be detected with high accuracy. In particular, by monitoring using multiple parameters, it is possible to further increase the accuracy of abnormalities.

[0115] The monitoring device 50 may obtain, as the voltage information, information on the assembled battery voltage Vb and information on the cell voltage Vc from different sources. For example, the monitoring device 50 may obtain the assembled battery voltage information from the EPU 15 and the cell voltage information from the BMS 16. Reliability can be improved by monitoring using data obtained by different independent measurements, that is, by multiplexing the diagnosis.

[0116] The monitoring device 50 may diagnose whether the abnormality detection is being performed normally by using the battery pack voltage Vb and the total voltage obtained by adding up all the cell voltages Vc in the battery pack 141. This can prevent erroneous determination of the abnormality detection.

[0117] During a predetermined period of transition between vertical and horizontal movement, the monitoring device 50 may limit the detection of anomalies, apply the threshold value before the transition, or apply the upper or lower limit voltage allowed for the battery 14 as the threshold value. This makes it possible to suppress erroneous determinations due to normal sudden fluctuations in battery voltage information, delays in fluctuations in battery voltage due to normal transient responses, and delays in threshold switching. This makes it possible to increase the reliability of anomaly detection.

[0118] The monitoring method of this embodiment is executed by a processor to monitor the battery 14. The monitoring method includes acquiring voltage information and travel mode information of the battery 14 during flight, and outputting a monitoring result if a predetermined condition related to an abnormality of the battery 14 is satisfied using the voltage information and a threshold value set for each travel mode. In this way, since a threshold value set for each travel mode is used, an abnormality in the battery 14 can be detected early. Therefore, flight safety can be improved.

[0119] The program of this embodiment is stored in a storage medium to monitor the battery 14 and includes instructions to be executed by a processor. The program includes instructions to acquire voltage information and travel mode information of the battery 14 during flight, and output a monitoring result when a predetermined condition related to an abnormality of the battery 14 is satisfied using the voltage information and a threshold value set for each travel mode. In this way, since a threshold value set for each travel mode is used, an abnormality of the battery 14 can be detected early. Therefore, flight safety can be improved.

[0120] (Other embodiments) The disclosure in this specification and drawings, etc. is not limited to the exemplified embodiments. The disclosure includes the exemplified embodiments and modifications by those skilled in the art based thereon. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented by various combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes the omission of parts and / or elements of the embodiments. The disclosure includes the substitution or combination of parts and / or elements between one embodiment and another embodiment. The disclosed technical scope is not limited to the description of the embodiments. Some disclosed technical scopes are indicated by the description of the claims, and should be interpreted as including all modifications within the meaning and scope equivalent to the description of the claims.

[0121] The disclosure in the specification and drawings is not limited by the claims. The disclosure in the specification and drawings includes the technical ideas described in the claims, and extends to more diverse and broader technical ideas than the technical ideas described in the claims. Therefore, various technical ideas can be extracted from the disclosure in the specification and drawings without being bound by the claims.

[0122] When an element or layer is referred to as being "on," "coupled," "connected," or "bonded," it may be directly coupled, connected, or bonded to another element or layer, and intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly coupled," "directly connected," or "directly bonded" to another element or layer, there are no intervening elements or layers. Other words used to describe relationships between elements should be construed in a similar manner (e.g., "between" vs. "directly between," "adjacent" vs. "directly adjacent," etc.). As used in this specification, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0123] The various flowcharts shown in this disclosure are all examples, and the number of steps constituting the flowcharts and the order of execution of the processes can be changed as appropriate. In addition, the apparatus, system, and method thereof described in this disclosure may be realized by a dedicated computer comprising a processor programmed to execute one or more functions embodied in a computer program. The apparatus and method described in this disclosure may be realized using a dedicated hardware logic circuit. Furthermore, the apparatus and method described in this disclosure may be realized by one or more dedicated computers configured by a combination of a processor executing a computer program and one or more hardware logic circuits.

[0124] For example, some or all of the functions of processor 311 may be realized as hardware. A form in which a certain function is realized as hardware includes a form in which it is realized using one or a plurality of ICs. As the processor (computation core), a CPU, MPU, GPU, DFP, etc. can be adopted. CPU is an abbreviation for Central Processing Unit. MPU is an abbreviation for Micro-Processing Unit. GPU is an abbreviation for Graphics Processing Unit. DFP is an abbreviation for Data Flow Processor.

[0125] Some or all of the functions of the processor 201 may be realized by combining a plurality of types of arithmetic processing devices. Some or all of the functions of the processor 201 may be realized by using an SoC, an ASIC, an FPGA, or the like. SoC is an abbreviation for System on Chip. ASIC is an abbreviation for Application Specific Integrated Circuit. FPGA is an abbreviation for Field-Programmable Gate Array. The same applies to the processor 311.

[0126] The computer program may be stored in a computer-readable non-transitory tangible storage medium as instructions executed by a computer. A HDD, SSD, flash memory, etc. may be used as a storage medium for the program. HDD is an abbreviation for Hard-disk Drive. SSD is an abbreviation for Solid State Drive. The scope of the present disclosure also includes forms such as a program for causing a computer to function as a control device or control system, and a non-transitory tangible storage medium such as a semiconductor memory on which the program is recorded.

[0127] (Disclosure of technical ideas) This specification discloses multiple technical ideas described in the following multiple dependent claims. Some of the claims may be described in a multiple dependent form, where the subsequent claim alternatively refers to the preceding claim. Furthermore, some of the claims may be described in a multiple dependent form, where the subsequent claim alternatively refers to the preceding claim. The claims described in these multiple dependent forms define multiple technical ideas.

[0128] <Technical philosophy 1> A monitoring device for monitoring a battery (14) mounted on an electric flying object (10), comprising: an acquisition unit (51) that acquires voltage information of the battery during flight and information related to a travel mode of the electric flying object; an output unit (53) that outputs a monitoring result when a predetermined condition related to an abnormality in the battery is satisfied using the voltage information and a threshold value set for each of the travel modes; A monitoring device comprising:

[0129] <Technical philosophy 2> The monitoring device according to Technical Idea 1, wherein the maximum discharge rate of the battery during vertical movement of the electric flying object is 1.5 times or more than the maximum discharge rate during horizontal movement.

[0130] <Technical philosophy 3> The monitoring device according to Technical Idea 2, wherein the discharge rate during the vertical movement is 3C or more.

[0131] <Technical philosophy 4> The monitoring device according to any one of Technical Ideas 1 to 3, wherein the acquisition unit acquires discharge characteristic information of the battery and / or flight information as information relating to the travel mode.

[0132] <Technical philosophy 5> The acquisition unit acquires the discharge characteristic information and the battery state information as information related to the travel mode, The monitoring device according to Technical Concept 4 further comprises a setting unit (54) that sets the threshold for each of the travel modes based on the discharge characteristic information and the battery state information.

[0133] <Technical philosophy 6> The monitoring device described in Technical Idea 5, wherein the battery status information includes information on an increase in resistance caused by a concentration bias of ions that contribute to the battery reaction.

[0134] <Technical philosophy 7> The monitoring device described in Technical Idea 5 or Technical Idea 6, wherein the setting unit uses the battery status information that is updated before flight by a battery status diagnosis performed when the aircraft is parked.

[0135] <Technical philosophy 8> The monitoring device according to any one of Technical Ideas 5 to 7, wherein the setting unit successively changes the set threshold value based on a change in battery state during flight.

[0136] <Technical philosophy 9> The battery includes a battery pack (141) including a plurality of battery cells (142), The monitoring device described in any one of Technical Ideas 1 to 8, wherein the acquisition unit acquires at least one of the absolute value of the assembled battery voltage, the absolute value of the cell voltage, the rate of change of the assembled battery voltage, the rate of change of the cell voltage, and the variation of the cell voltage as the voltage information.

[0137] <Technical Thought 10> The monitoring device according to Technical Idea 9, wherein the acquisition unit acquires, as the voltage information, information relating to the battery pack voltage and information relating to the cell voltage from different acquisition targets.

[0138] <Technical Thought 11> The monitoring device described in Technical Idea 10 includes a diagnostic unit (52) that diagnoses whether abnormality detection is being performed normally using the assembled battery voltage and a total voltage obtained by adding up all of the cell voltages in the assembled battery.

[0139] <Technical Thought 12> A monitoring device as described in any one of Technical Ideas 1 to 11, comprising a limiting unit (52) that performs one of the following during a predetermined period during the transition between vertical movement and horizontal movement: limiting the detection of abnormalities, applying the threshold value before the transition, and applying an upper limit voltage or a lower limit voltage allowable for the battery as the threshold value. [Explanation of symbols]

[0140] 10... eVTOL, 11... aircraft body, 12... fixed wing, 121... main wing, 122... tail, 13... rotor, 131... blade, 132... shaft, 14... battery, 141... battery pack, 142... battery cell, 142N, 142P... electrode terminal, 15... EPU, 16... BMS, 20... ECU, 201... processor, 202... memory, 203... storage, 203P... program, 204... communication circuit, 30... ground station, 31... server, 311... processor, 312... memory, 313... storage, 313P... program, 314... communication circuit, 40... flight control system, 41... external management unit, 42... internal management unit, 50... monitoring device, 51... acquisition unit, 52... determination unit, 53... output unit, 54... setting unit< / evtol>

Claims

1. A monitoring device for monitoring a battery (14) mounted on an electric flying object (10), comprising: An acquisition unit (51) that acquires voltage information of the battery during flight and information regarding a travel mode of the electric flying object; an output unit (53) that outputs a monitoring result when a predetermined condition related to an abnormality of the battery is satisfied using the voltage information and a threshold value set for each of the travel modes; A monitoring device comprising:

2. 2. The monitoring device according to claim 1, wherein a maximum discharge rate of the battery during vertical movement of the electric flying object is 1.5 times or more than a maximum discharge rate during horizontal movement.

3. The monitoring device according to claim 2 , wherein the discharge rate during the vertical movement is 3C or more.

4. The monitoring device according to claim 1 , wherein the acquisition unit acquires, as the information relating to the travel mode, discharge characteristic information of the battery and / or flight information.

5. The acquisition unit acquires the discharge characteristic information and the battery state information as information related to the travel mode, The monitoring device according to claim 4 , further comprising a setting unit (54) that sets the threshold for each of the travel modes based on the discharge characteristic information and the battery state information.

6. The monitoring device according to claim 5 , wherein the battery state information includes information on an increase in resistance caused by a concentration bias of ions that contribute to a battery reaction.

7. The monitoring device according to claim 5 , wherein the setting unit uses the battery status information that is updated before flight by a battery status diagnosis performed when the aircraft is parked.

8. The monitoring device according to any one of claims 5 to 7, wherein the setting unit sequentially changes the set threshold value based on a change in battery state during flight.

9. The battery includes a battery pack (141) including a plurality of battery cells (142), The monitoring device according to claim 1 , wherein the acquisition unit acquires, as the voltage information, at least one of an absolute value of an assembled battery voltage, an absolute value of a cell voltage, a rate of change of the assembled battery voltage, a rate of change of the cell voltage, and a variation of the cell voltage.

10. The monitoring device according to claim 9 , wherein the acquisition unit acquires, as the voltage information, information relating to the battery pack voltage and information relating to the cell voltage from different acquisition targets.

11. 11. The monitoring device according to claim 10, further comprising a diagnosis unit (52) that diagnoses whether abnormality detection is being performed normally, using the assembled battery voltage and a total voltage obtained by adding up all of the cell voltages in the assembled battery.

12. 2. The monitoring device of claim 1, further comprising a limiting unit (52) that performs one of the following during a predetermined period during a transition between vertical movement and horizontal movement: limiting detection of anomalies, applying the threshold value before the transition, and applying an upper limit voltage or a lower limit voltage allowable for the battery as the threshold value.

13. A monitoring method executed by a processor (201) for monitoring a battery (14) on board an electric flying vehicle (10), comprising: Acquire voltage information of the battery during flight and information regarding a travel mode of the electric flying object; outputting a monitoring result when a predetermined condition regarding an abnormality of the battery is satisfied using the voltage information and a threshold value set for each of the travel modes; A monitoring method comprising:

14. A program stored in a storage medium (203) for monitoring a battery (14) installed in an electric flying object (10), the program including instructions to be executed by a processor (201), Acquiring voltage information of the battery during flight and information regarding a travel mode of the electric flying object; outputting a monitoring result when a predetermined condition regarding an abnormality of the battery is satisfied using the voltage information and a threshold value set for each of the travel modes; A program comprising the instructions for causing a program to execute the above.

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