System

Abstract

A system is provided with: a plurality of switching units which are connected in parallel to a bus line to which a power generation unit and a load are connected, and which respectively switch the ON / OFF of the connection of a battery pack to the bus line; the plurality of battery packs are respectively connected with the plurality of switching parts; and a management unit that manages the plurality of switching units so as to alternately discharge the plurality of battery packs, such that the discharge rate of each of the plurality of battery packs is higher than when all of the plurality of battery packs are discharged, at least one of the plurality of switching units has a discharge FET and a charge FET, and the discharge rate of each of the plurality of battery packs is higher than when all of the plurality of battery packs are discharged. The discharge FET and the charge FET can be switched between a discharge state in which current flows from the connected battery pack to the bus line, a charge state in which current flows from the bus line to the battery pack, and a cut-off state in which current flows from the bus line to the battery pack. The cut-off state is a state in which current does not flow between the bus line and the battery pack.

Description

Technical Field

[0001] The present invention relates to a system. Background Art

[0002] There is known a device such as a HAPS (High Altitude Platform Station) that discharges the power of a battery at a relatively low discharge rate to execute various operations (for example, refer to Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-043494 Summary of the invention

[0006] According to one embodiment of the present invention, a system is provided. Alternatively, the system may include a plurality of switching units connected in parallel with a bus connected to a power generation unit and a load and switching on and off the connection of a battery pack to the bus. Alternatively, the system may include a plurality of battery packs connected to the plurality of switching units. Alternatively, the system may include a management unit that manages the plurality of switching units in a manner that the plurality of battery packs are alternately discharged, so that the discharge rate of each of the plurality of battery packs becomes higher than when all the plurality of battery packs are discharged. Alternatively, at least one of the plurality of switching units may include a discharge FET and a charge FET, and the discharge FET and the charge FET may be switched between a discharge state, a charge state, and a cut-off state, wherein the discharge state is a state in which current flows from the connected battery pack to the bus, the charge state is a state in which current flows from the bus to the battery pack, and the cut-off state is a state in which current does not flow between the bus and the battery pack.

[0007] In the system, a part of the plurality of switching parts may include the discharge FET and the charge FET, and another part of the plurality of switching parts may include: a contactor connected to the bus; and the discharge FET and the charge FET connected in series between the contactor and the battery pack. The management unit may maintain the contactor of the other part of the plurality of switching parts in an open state while a predetermined condition is satisfied. The management unit may maintain the contactor of the other part of the plurality of switching parts in an open state while the system is located in an area where lightning occurs. The management unit may maintain the contactor of the other part of the plurality of switching parts in an open state when at least one of the discharge FET and the charge FET of the other part of the plurality of switching parts has a malfunction. The contactor may be of a type that opens when a control current is applied, or the management unit may apply the control current to the contactor while the predetermined condition is satisfied.

[0008] In any of the above systems, a part of the plurality of switching parts may include the discharge FET and the charge FET, and another part of the plurality of switching parts may include a contactor, and the contactor may switch the connection and disconnection of the current between the connected battery pack and the bus. It is also possible that during charging, the management unit sets the part of the plurality of switching parts to the charging state and turns on the contactors of the other part of the plurality of switching parts, and during discharging, the management unit turns on the contactors of the other part of the plurality of switching parts and alternately sets the part of the plurality of switching parts to the discharge state. It is also possible that during discharging, the management unit alternately sets the part of the plurality of switching parts to the discharge state in a manner that does not cause all the switching parts to be in the discharge state at the same time.

[0009] In any of the above systems, all of the plurality of switching units may include the discharge FET and the charge FET.

[0010] In any of the systems, all of the plurality of switching units may include: a contactor connected to the bus; and the discharge FET and the charge FET connected in series between the contactor and the battery pack. The management unit may maintain the contactors of a part of the plurality of switching units in an open state during a period in which a predetermined condition is satisfied. The management unit may turn on only the contactors of a part of the plurality of switching units while the system is located in an area where lightning occurs, and maintain the contactors of the other switching units in an open state. The contactors of the plurality of switching units may be of a type that is opened when a control current is applied, or the management unit may apply the control current to the contactors of the other switching units in the plurality of switching units while the system is located in an area where lightning occurs.

[0011] In any of the systems, the management unit may control the multiple switching units in a manner that causes the multiple battery packs to discharge alternately so that the difference in voltage between the battery pack with the largest voltage and the battery pack with the smallest voltage among the multiple battery packs is not greater than a voltage threshold.

[0012] In any of the above systems, the management unit may control the plurality of switching units so that the plurality of battery packs are simultaneously charged with the electric power generated by the power generation unit.

[0013] In any of the systems, the system may be mounted on an aircraft, the plurality of battery packs may be arranged on the wings of the aircraft, the power generation unit may perform solar power generation, or the load may be a motor that rotates a propeller of the aircraft. The system may include the aircraft. The aircraft may include a communication control unit that uses the power discharged from the plurality of battery packs to provide wireless communication services to user terminals within a communication area formed by irradiating beams toward the ground.

[0014] In addition, the above summary of the invention does not list all the necessary features of the present invention. In addition, sub-combinations of these feature groups may also constitute inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 An example of system 10 is schematically shown.

[0016] Figure 2 An example of system 10 is shown schematically.

[0017] Figure 3 An example of the flow of current during charging in the system 10 is schematically shown.

[0018] Figure 4 An example of the flow of current during discharge in the system 10 is schematically shown.

[0019] Figure 5 An example of the functional structure of the management device 100 is schematically shown.

[0020] Figure 6 Another example of the flow of current during discharge in the system 10 is schematically shown.

[0021] Figure 7 An example of the configuration of the plurality of switching units 210 is schematically shown.

[0022] Figure 8 Another example of the configuration of the plurality of switching units 210 is schematically shown.

[0023] Fig. 9 Another example of the configuration of the plurality of switching units 210 is schematically shown.

[0024] Fig.10 An example of the structure of the switching unit 210 including the contactor 214, the discharge FET, and the charge FET is schematically shown.

[0025] Fig.11 An example of an aircraft 600 carrying the system 10 is schematically shown.

[0026] Fig.12 Another example of an aircraft 600 equipped with the system 10 is schematically shown.

[0027] Fig.13 Another example of an aircraft 600 equipped with the system 10 is schematically shown.

[0028] Fig.14 Another example of an aircraft 600 equipped with the system 10 is schematically shown.

[0029] Fig.15 An example of a HAPS 700 equipped with the system 10 is schematically shown.

[0030] Fig.16 An example of the hardware configuration of a computer 1200 functioning as the management device 100 is schematically shown. DETAILED DESCRIPTION

[0031] Batteries (especially batteries using lithium metal negative electrodes) have the characteristic of deteriorating quickly when the discharge rate is low. As one of the countermeasures to this problem, a technology has been proposed for alternating between multiple battery packs to increase the discharge rate of each battery pack. As a switching unit for switching the battery packs, any switching unit can be used as long as it can connect and disconnect the battery packs, but since the characteristics vary depending on the switching unit used, it is sometimes necessary to conduct research corresponding to the characteristics. In the system 10 involved in the present embodiment, switching control is implemented that takes such characteristics into consideration. In addition, in the system 10 involved in the present embodiment, battery charge and discharge management that takes the above-mentioned battery characteristics into consideration is implemented.

[0032] Hereinafter, the present invention will be described by way of the embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, the combination of features described in the embodiments is not necessarily all essential to the solution means of the invention.

[0033] Figure 1 An example of the system 10 is schematically shown. The system 10 includes a management device 100. The management device 100 manages a plurality of battery groups 200 connected in parallel to a bus 400 to which a plurality of power generation units 300 and a plurality of loads 500 are connected. Alternatively, the management device 100 manages charging and discharging of the plurality of battery groups 200.

[0034] The system 10 may include a plurality of battery packs 200. The system 10 may include a plurality of power generation units 300. The system 10 may include a plurality of loads 500.

[0035] The battery of the battery pack 200 may be any type. The battery pack 200 is, for example, a battery using lithium as a negative electrode. The battery pack 200 is, for example, a lithium ion battery. The battery pack 200 may include a lithium metal battery.

[0036] The battery pack 200 includes a plurality of cells 202. The cells 202 may be, for example, battery cells using metallic lithium as a negative electrode.

[0037] The power generation unit 300 performs solar power generation, for example. The power generation method of the power generation unit 300 may be other power generation methods. The battery pack 200 can be charged by the power generated by the power generation unit 300. A plurality of power generation units 300 may be connected in parallel to the bus 400.

[0038] The load 500 consumes the power of the battery pack 200 or consumes the power generated by the power generation unit 300. Alternatively, the load 500 may be any device that is operated by power. For example, when the system 10 is mounted on an aircraft, the load 500 may be a device related to the flight of the aircraft, such as a propeller or an elevator.

[0039] The management device 100 according to the present embodiment may manage the charging and discharging of the plurality of battery packs 200 so as to suppress the degradation of the plurality of battery packs 200 .

[0040] Figure 2 An example of system 10 is schematically shown. Figure 2 In the example shown, a plurality of battery packs 200 are connected to the bus 400 via a switching unit 210 that switches the connection of the battery packs 200 to the bus 400. A plurality of switching units 210 are connected in parallel to the bus 400, and each of the plurality of battery packs 200 is connected to the plurality of switching units 210. In addition, a plurality of solar cells 310 are connected to the bus 400 via an MPPT (Maximum Power Point Tracking) 320. The solar cell 310 may be an example of a power generation unit 300. In addition, a plurality of loads 500 are connected to the bus 400 via a controller 510. Here, a load 500 on the left side of the left side of the bus 400 and a load 500 on the right side of the right side of the bus 400 are illustrated.

[0041] When describing the battery packs 200 separately, they may be described as battery pack A, battery pack B, battery pack C, battery pack D, battery pack E, battery pack F, battery pack G, and battery pack H from left to right. When describing the switching units 210 separately, they may be described as switching unit A, switching unit B, switching unit C, switching unit D, switching unit E, switching unit F, switching unit G, and switching unit E from left to right.

[0042] Figure 3 An example of the flow of current during charging in the system 10 is schematically shown. Figure 3 As illustrated, the management device 100 may control the electrical connection of the plurality of battery groups 200 to the bus 400 so that the plurality of battery groups 200 are simultaneously charged with the power generated by the plurality of solar cells 310. For example, when the plurality of solar cells 310 start generating power, the management device 100 controls all the switching units 210 so that all the battery groups 200 are electrically connected to the bus 400.

[0043] Figure 4 This schematically shows an example of the flow of current during discharge in the system 10. The management device 100 may control the plurality of switching units 210 so that the plurality of battery packs 200 are alternately discharged, and the discharge rate of each of the plurality of battery packs 200 becomes higher than when all the plurality of battery packs 200 are discharged.

[0044] The management device 100 controls the plurality of switching units 210, for example, so that the plurality of battery groups 200 are discharged one by one in sequence. The management device 100 controls the plurality of switching units 210, for example, so that the battery group A, the battery group B, the battery group C, the battery group D, the battery group E, the battery group F, the battery group G, and the battery group H are discharged in a repeated order. In addition, the management device 100 controls the plurality of switching units 210, for example, so that the battery group 200 with a higher voltage among the plurality of battery groups 200 is discharged in sequence with priority. In this way, by alternately discharging the eight battery groups 200, the discharge rate of the battery groups 200 can be increased by eight times compared to the case where all eight battery groups 200 are discharged.

[0045] The management device 100 switches the charging and discharging of the multiple battery packs 200 according to the situation. For example, when all the battery packs 200 are set to be electrically connected to the bus 400 for charging, if the difference between the voltage of the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage among the multiple battery packs 200 is large, the current flows from the former to the latter, making the charging rate of the latter faster, which may accelerate the degradation of the latter.

[0046] Alternatively, the management device 100 controls the plurality of switching units 210 so that the plurality of battery groups 200 are alternately discharged, so that the difference between the voltage of the battery group 200 with the largest voltage and the battery group 200 with the smallest voltage among the plurality of battery groups 200 is not greater than a predetermined voltage threshold. In other words, the management device 100 controls the plurality of switching units 210 so that the plurality of battery groups 200 are alternately discharged, so that the difference between the remaining capacity of the battery group 200 with the largest remaining capacity and the battery group 200 with the smallest remaining capacity among the plurality of battery groups 200 is not greater than a predetermined remaining capacity threshold.

[0047] For example, the management device 100 first starts discharging the battery group 200 with the largest voltage among the plurality of battery groups 200 (sometimes described as the first battery group 200). The management device 100 starts discharging the second battery group 200 before the difference between the voltage of the first battery group 200 and the voltage of the battery group 200 with the largest voltage among the other plurality of battery groups 200 (sometimes described as the second battery group 200) exceeds the voltage threshold. The management device 100 stops discharging the first battery group 200 after a predetermined time has passed since the start of discharging of the second battery group 200. By repeating such control, the difference between the voltage of the battery group 200 with the largest voltage and the battery group 200 with the smallest voltage among the plurality of battery groups 200 can be made not to exceed the predetermined voltage threshold. In addition, the predetermined time may be, for example, about 0.01 to 1 second. By stopping the discharge of the first battery pack 200 after a predetermined time has passed since the start of the discharge of the second battery pack 200 , the discharge can be prevented from being interrupted.

[0048] Figure 5 The following schematically shows an example of the functional configuration of the management device 100. The management device 100 may include the management unit 110, the group-related information acquisition unit 112, the estimation unit 114, and the reception unit 116. The management device 100 does not necessarily have to include all of these.

[0049] The management unit 110 controls the plurality of switching units 210 so that the plurality of battery packs 200 are alternately discharged, and the discharge rate of each of the plurality of battery packs 200 becomes higher than when all the plurality of battery packs 200 are discharged.

[0050] Alternatively, the management unit 110 controls the multiple switching units 210 so that the multiple battery packs 200 are alternately discharged so that the voltage difference between the battery pack 200 with the highest voltage and the battery pack 200 with the lowest voltage among the multiple battery packs 200 is not greater than a predetermined voltage threshold.

[0051] For example, the management unit 110 first starts discharging the battery group 200 (sometimes referred to as the first battery group 200) with the largest voltage among the plurality of battery groups 200. Next, the management unit 110 starts discharging the second battery group 200 before the difference between the voltage of the first battery group 200 and the voltage of the battery group 200 (sometimes referred to as the second battery group 200) with the largest voltage among the other plurality of battery groups 200 becomes greater than a predetermined voltage threshold. Then, the management unit 110 stops discharging the first battery group 200 after a predetermined time has passed since the start of discharging the second battery group 200. The management unit 110 discharges the plurality of battery groups 200 in sequence by repeating such control.

[0052] Alternatively, the management unit 110 controls the electrical connection of the plurality of battery packs 200 to the bus 400 so that the plurality of battery packs 200 are simultaneously charged with the power generated by the plurality of solar cells 310. For example, the management unit 110 controls the plurality of switching units 210 so that the plurality of battery packs 200 are simultaneously charged with the power generated by the plurality of solar cells 310.

[0053] Alternatively, the management unit 110 manages in such a manner that, when charging the plurality of battery groups 200 with the power generated by the plurality of solar cells 310, the voltage of the bus line 400 from the solar cells 310 is between the voltage of the battery group 200 with the largest voltage and the voltage of the battery group 200 with the smallest voltage among the plurality of battery groups 200. Alternatively, the management unit 110 manages in such a manner that, by controlling the plurality of MPPTs 320, the voltage of the bus line 400 from the solar cells 310 is between the voltage of the battery group 200 with the largest voltage and the voltage of the battery group 200 with the smallest voltage among the plurality of battery groups 200.

[0054] The group-associated information acquisition unit 112 acquires group-associated information related to the battery packs 200 for each of the plurality of battery packs 200. For example, the group-associated information acquisition unit 112 acquires information detected by the sensors respectively arranged for the plurality of battery packs 200 as the group-associated information.

[0055] Alternatively, the group-related information may include the OCV (Open Circuit Voltage) of the battery pack 200. Alternatively, the group-related information may include the CCV (Closed Circuit Voltage) of the battery pack 200. Alternatively, the group-related information may include the DCIR (Direct Current Internal Resistance) of the battery pack 200. Alternatively, the group-related information may include the SOH (State Of Health) of the battery pack 200. Alternatively, the group-related information may include the SOC (State Of Charge) of the battery pack 200. Alternatively, the group-related information may include the current value of the battery pack 200. Alternatively, the group-related information may include the discharge time of the battery pack 200. Alternatively, the group-related information may include the cumulative capacity of the battery pack 200. Alternatively, the group-related information may include the temperature of the battery pack 200.

[0056] The estimating unit 114 estimates the state of the battery pack 200 based on the group-related information acquired by the group-related information acquiring unit 112. The estimating unit 114 can perform the estimation using an estimation method used in an existing BMS (Battery Management System).

[0057] For example, the estimation unit 114 stores the relationship between the SOC and DCIR of the battery pack 200 in advance, and estimates the OCV of the battery pack 200 based on the stored DCIR, SOH, current value, discharge time, CCV, and cumulative capacity.

[0058] In addition, for example, the estimation unit 114 first estimates the SOC and SOH before the start of discharge based on the OCV, current value, discharge time, CCV, cumulative capacity, and temperature before the start of discharge. Next, the estimation unit 114 uses the data to estimate the current DCIR based on a pre-stored database. Then, the estimation unit 114 estimates the current OCV based on the estimated current DCIR, CCV, and current value.

[0059] Alternatively, the management unit 110 controls the multiple switching units 210 in a manner that causes the multiple battery packs 200 to discharge alternately based on the OCV of each of the multiple battery packs 200 obtained by the group association information acquisition unit 112, so that the difference in voltage between the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage among the multiple battery packs 200 is not greater than a predetermined voltage threshold.

[0060] Alternatively, the management unit 110 may control the multiple switching units 210 in such a manner that the multiple battery packs 200 are alternately discharged based on the OCV of each of the multiple battery packs 200 estimated by the estimation unit 114, so that the difference in voltage between the battery pack 200 having the largest voltage and the battery pack 200 having the smallest voltage among the multiple battery packs 200 is not greater than a predetermined voltage threshold.

[0061] Alternatively, the management unit 110 may predetermine a voltage threshold value so that the charging rate from the battery pack 200 with the highest voltage to the battery pack 200 with the lowest voltage does not become faster than a predetermined charging rate threshold value. The charging rate threshold value may be, for example, 0.3C or less, and more preferably, 0.2C or less.

[0062] For example, when using a battery pack 200 of 5 kWh (15 Ah), a minimum DICR of 1.87 Ω, an average DICR of 1.99 Ω, and a voltage of 270 to 396 V, in order to make the DCIR 2 Ω, the charge is set to 0.2C at 3 A, the voltage difference between the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage is <(0.2 (C) × 15 (Ah) × 2 (Ω) = 6 V), and the voltage threshold is 6 V. In this case, after the management unit 110 starts discharging the battery pack 200 with the largest voltage (recorded as the first battery pack 200), before the voltage of the first battery pack 200 becomes lower than the voltage of the battery pack 200 with the second highest voltage (recorded as the second battery pack 200) by 6 V or more, the management unit 110 starts discharging the second battery pack 200, and stops discharging the first battery pack 200 after a predetermined time has passed.

[0063] In addition, in order to set 0.3C, the voltage difference between the battery group 200 with the largest voltage and the battery group 200 with the smallest voltage is <(0.3(C)×15(Ah)×2(Ω)=9V), and the voltage threshold is 9V. In this case, after the management unit 110 starts discharging the first battery group 200, before the voltage of the first battery group 200 becomes lower than the voltage of the second battery group 200 by 9V or more, the management unit 110 starts discharging the second battery group 200, and stops discharging the first battery group 200 after a predetermined time has passed.

[0064] Alternatively, the management unit 110 may manage in the following manner, for example, when the power generation of the solar cell 310 increases and there is surplus power generation, the power generated by the solar cell 310 is consumed so that the charging rate of the plurality of battery groups 200 is not faster than the charging rate threshold. For example, the management unit 110 controls the controller 510 in such a manner that the load 500 consumes the power generated by the solar cell 310 so that the charging rate of the plurality of battery groups 200 is not faster than the charging rate threshold.

[0065] Alternatively, the management unit 110 manages in such a manner that, when the discharge rate of a battery pack 200 being discharged among the plurality of battery packs 200 is slower than a predetermined discharge rate threshold for a predetermined period of time, the power consumption of the battery pack 200 being discharged is increased. For example, the management unit 110 controls the controller 510 in such a manner that the load 500 consumes the power of the battery pack 200. Alternatively, the predetermined time may be arbitrarily set in seconds or minutes. Thus, it is possible to prevent the battery pack 200 from being deteriorated prematurely due to a long-term continuation of a low discharge rate state. The discharge rate threshold may be 0.3C to 2.0C, and more preferably, may be 0.4C to 1.0C.

[0066] Table 1 below shows the experimental results of the degradation degree of the battery pack 200 having a battery cell using metal lithium as a negative electrode at each of various discharge rates and charge rates. The experiment was performed multiple times for each combination of discharge rate and charge rate, and the case where 80% of the initial capacity was maintained for an average of more than 250 cycles was set as "◎", the case where 80% of the initial capacity was maintained for an average of more than 200 cycles and less than 250 cycles was set as "○", and the case where the average was less than 180 cycles was set as "×". The experimental results show that, for example, for each of the plurality of battery packs 200, the result of repeatedly discharging at a discharge rate of 0.3C and charging at a charge rate of 0.1C is that the case where 80% of the initial capacity is maintained is an average of more than 200 cycles and less than 250 cycles. In addition, for example, for each of the plurality of battery packs 200, the result of repeatedly discharging at a discharge rate of 0.5C and charging at a charge rate of 0.2C shows that since 80% of the initial capacity is maintained, it is an average of more than 250 cycles.

[0067] [Table 1]

[0068]

[0069] As shown in Table 1, the discharge rate is preferably 0.3 C to 2.0 C, and more preferably 0.4 C to 1.0 C. The charge rate is preferably 0.3 C or less, and more preferably 0.2 C or less.

[0070] The receiving unit 116 receives various information from the outside. The receiving unit 116 receives, for example, a control instruction for the management unit 110. Alternatively, the management unit 110 controls the plurality of switching units 210 according to the control instruction received by the receiving unit 116. The receiving unit 116 receives, for example, weather information of the area where the system 10 is located. Alternatively, the management unit 110 controls the plurality of switching units 210 based on the weather information received by the receiving unit 116.

[0071] Figure 6 Another example of the flow of current during discharge in the system 10 is schematically shown. The management unit 110 may control the plurality of switching units 210 so that the plurality of battery packs 200 are discharged in sequence two or more at a time. For example, the management unit 110 controls the plurality of battery packs 200 so that two battery packs 200 are discharged in sequence at a time. Also, for example, the management unit 110 controls the plurality of battery packs 200 so that three battery packs are discharged in sequence at a time. Also, for example, the management unit 110 controls the plurality of battery packs 200 so that four battery packs are discharged in sequence at a time. These are examples, and the management unit 110 may control the plurality of battery packs 200 so that a larger number of battery packs 200 are discharged in sequence each time.

[0072] The management unit 110 may perform control on the plurality of left battery packs 200 and the plurality of right battery packs 200 so that the left and right voltage differences do not deviate significantly.

[0073] For example, the management unit 110 discharges the left and right sides alternately, such as one on the left, one on the right, one on the left, and one on the right, for a plurality of left battery packs 200 and a plurality of right battery packs 200. By discharging the left battery pack 200 and the right battery pack 200 alternately, the voltage difference between the left and right sides can be prevented from increasing.

[0074] At this time, the management unit 110 may discharge the left side and the right side alternately in consideration of the positional relationship between the plurality of left battery packs 200 and the plurality of right battery packs 200. For example, the management unit 110 discharges the left side and the right side alternately, such as the left battery pack 200, the right battery pack 200 corresponding to the left battery pack 200 in position, the next left battery pack 200, and the right battery pack 200 corresponding to the left battery pack 200 in position. The corresponding position may be, for example, a left-right symmetrical position. For example, after discharging the first battery pack 200, the management unit 110 discharges the eighth battery pack 200 at a left-right symmetrical position, after discharging the second battery pack 200, the management unit 110 discharges the seventh battery pack 200 at a left-right symmetrical position, after discharging the third battery pack 200, the management unit 110 discharges the sixth battery pack 200 at a left-right symmetrical position, and after discharging the fourth battery pack 200, the management unit 110 discharges the fifth battery pack 200 at a left-right symmetrical position.

[0075] In addition, for example, the management unit 110 may discharge the left and right sides alternately without considering the positional relationship between the plurality of left battery packs 200 and the plurality of right battery packs 200. For example, the management unit 110 discharges any one of the fifth to eighth battery packs 200 after discharging the first battery pack 200, discharges any one of the remaining three of the fifth to eighth battery packs 200 after discharging the second battery pack, discharges any one of the remaining two of the fifth to eighth battery packs 200 after discharging the third battery pack 200, and discharges the remaining one of the fifth to eighth battery packs 200 after discharging the fourth battery pack 200.

[0076] In addition, for example, the management unit 110 may control the plurality of switching units 210 so that each of the plurality of left battery packs 200 and the plurality of right battery packs 200 is discharged one by one in sequence. In this case, the management unit 110 may control the plurality of switching units 210 so that each of the plurality of left battery packs 200 and the plurality of right battery packs 200 is discharged one by one in sequence in consideration of the positional relationship between the plurality of left battery packs 200 and the plurality of right battery packs 200. For example, the management unit 110 may control the plurality of switching units 210 so that each of the plurality of left battery packs 200 and the plurality of right battery packs 200 is discharged one by one in sequence in a bilaterally symmetrical manner.

[0077] The management unit 110 controls the plurality of switching units 210, for example, so that the first battery group 200 and the eighth battery group 200, the second battery group 200 and the seventh battery group 200, the third battery group 200 and the sixth battery group 200, and the fourth battery group 200 and the fifth battery group 200 are sequentially discharged. For example, when the first battery group 200 and the second battery group 200 are discharged, the power transmission path to the load 500 on the left side becomes shorter, but the power transmission path to the load 500 on the right side becomes longer, and the power transmission efficiency is poor. In contrast, by discharging symmetrically, the power transmission path to one of the load 500 on the left side and the load 500 on the right side can be prevented from becoming longer, and the reduction in power transmission efficiency can be suppressed. In addition, in this case, when the management unit 110 discharges the first battery group 200 and the eighth battery group 200, the first battery group 200 and the eighth battery group 200 can be discharged simultaneously, or can be discharged alternately, or can be discharged sequentially.

[0078] Alternatively, the management unit 110 controls the group of the first battery group 200 and the eighth battery group 200, the group of the second battery group 200 and the seventh battery group 200, the group of the third battery group 200 and the sixth battery group 200, and the group of the fourth battery group 200 and the fifth battery group 200 so that the group with a higher voltage is discharged first. For example, the management unit 110 determines the battery group 200 with a higher voltage for each of the plurality of groups, and causes the determined battery group 200 with a higher voltage to be discharged first. In addition, for example, the management unit 110 causes the group with a higher average voltage among the plurality of groups to be discharged first.

[0079] In addition, the management unit 110 may control the plurality of switching units 210 so that each of the plurality of left battery groups 200 and the plurality of right battery groups 200 is sequentially discharged one by one regardless of the positional relationship between the plurality of left battery groups 200 and the plurality of right battery groups 200. For example, the management unit 110 may manage the plurality of battery groups 200 so that each arbitrary combination of the plurality of left battery groups 200 and the plurality of right battery groups 200 is sequentially discharged. For example, the management unit 110 may manage the plurality of battery groups 200 so that each arbitrary combination of the plurality of left battery groups 200 and the plurality of right battery groups 200 is sequentially discharged. For example, the management unit 110 may manage the plurality of battery groups 200 so that each arbitrary combination of the plurality of left battery groups 200 and the plurality of right battery groups 200 is sequentially discharged by combining any one of the fifth battery group 200 to the eighth battery group 200 with the first battery group 200, combining any one of the remaining three of the fifth battery group 200 to the eighth battery group 200 with the second battery group 200, combining any one of the remaining two of the fifth battery group 200 to the eighth battery group 200 with the third battery group 200, and combining the remaining battery groups 200 of the fifth battery group 200 to the eighth battery group 200 with the fourth battery group 200, so that each combination is sequentially discharged.

[0080] For example, the management unit 110 determines the battery pack 200 with the higher voltage for each of the plurality of groups, and determines the order of the groups in descending order of voltage. Then, the management unit 110 discharges the battery packs 200 while switching the groups appropriately in the determined order, so that the voltage difference between the battery pack 200 with the highest voltage and the battery pack 200 with the lowest voltage among the plurality of battery packs 200 does not exceed the voltage threshold.

[0081] Figure 7 An example of the structure of the plurality of switching units 210 is schematically shown. In the system 10 according to the present embodiment, at least one of the plurality of switching units 210 includes a FET 211 (sometimes described as a discharge FET) and a FET 212 (sometimes described as a charge FET) that can be switched between a discharge state in which current flows from the connected battery pack 200 to the bus 400, a charge state in which current flows from the bus 400 to the battery pack 200, and a cut-off state in which current does not flow between the bus 400 and the battery pack 200.

[0082] Alternatively, both the discharge FET and the charge FET may be P-type FETs. Alternatively, both the discharge FET and the charge FET may be N-type FETs. The management unit 110 switches between the charge state, the discharge state, and the cut-off state by controlling the discharge FET and the charge FET. The discharge FET and the charge FET may be configured arbitrarily as long as they can switch between the charge state, the discharge state, and the cut-off state.

[0083] exist Figure 7In the example shown, all of the multiple switching units 210 have a discharge FET and a charge FET. The contactor mechanically controls the on and off, while the FET controls the on and off by electrical control. Therefore, compared with the case of using a contactor, by using a FET, the tolerance to the switching of on and off can be improved. In addition, compared with the structure in which a contactor is added to part or all of the multiple switching units 210, the overall weight can be reduced.

[0084] When discharging a plurality of battery packs 200 alternately, as described above, the management unit 110 may start discharging the next battery pack 200 while discharging one battery pack 200, and stop discharging the battery pack 200 after a predetermined time has passed. This allows uninterrupted discharging.

[0085] Compared with the contactor, the withstand voltage of the FET is lower, so, for example, when an overvoltage is applied due to a direct lightning strike on the system 10, a failure may occur. If the FET is damaged by lightning, there is a mode in which the current cannot be disconnected (not in a cut-off state) (sometimes recorded as mode A), a mode in which the current no longer flows (sometimes recorded as mode B), and a semi-damaged mode (sometimes recorded as mode C). In the case of mode A, the bus 400 and the battery pack 200 are always in an electrically connected state, and the deterioration of the battery pack 200 is accelerated, but there is no significant impact on the operation of the system 10. However, in the case of mode B, the power of the battery pack 200 cannot be used, which has a significant impact on the operation of the system 10. In addition, in the case of mode C, current flows in a state of high resistance, heat is generated, and it may even catch fire depending on the situation. By adopting various other mechanisms, the occurrence of such problems can be prevented or reduced, but it is preferably dealt with by the structure of multiple switching units 210.

[0086] Figure 8 Another example of the structure of the plurality of switching units 210 is schematically shown. Figure 8 As shown, the system 10 may be configured such that a portion of the plurality of switching units 210 includes a discharge FET and a charge FET, and another portion of the plurality of switching units 210 includes a contactor 214 for switching the current between the connected battery pack 200 and the bus 400 on and off.

[0087] In this way, since a part of the switching unit 210 is constituted by the contactor 214 , even if an overvoltage is applied to the system 10 , a part of the switching unit 210 can be prevented from being damaged, and at least a minimum function can be maintained.

[0088] Alternatively, during charging, the management unit 110 sets the switching unit 210 composed of the discharge FET and the charge FET to the charge state, and turns on the contactor 214 of the switching unit 210 composed of the contactor 214, thereby charging all of the plurality of battery packs 200. Alternatively, during discharging, the management unit 110 turns on the contactor 214 of the switching unit 210 composed of the contactor 214, and alternately sets the plurality of switching units 210 composed of the discharge FET and the charge FET to the discharge state. Alternatively, during the discharge, as described above, the management unit 110 sets one of the switching units 210 composed of the discharge FET and the charge FET to the discharge state, sets the next switching unit 210 to the discharge state, and sets one of the switching units 210 to the disconnection state after a predetermined time has elapsed.

[0089] In addition, during the discharge, the management unit 110 may alternately set the plurality of switch units 210 composed of the discharge FET and the charge FET to the discharge state so that they do not enter the discharge state at the same time. During the discharge, by maintaining the contactor 214 of the switch unit 210 composed of the contactor 214 turned on, the discharge can be prevented from being interrupted even if the switch unit 210 composed of the discharge FET and the charge FET is alternately turned on so that they do not enter the discharge state at the same time.

[0090] The ratio of the switch unit 210 having the discharge FET and the charge FET to the switch unit 210 having the contactor 214 may be any ratio. For example, by configuring one of the plurality of switch units 210 with the contactor 214, even when an overvoltage is applied to the system 10, the functions of at least one switch unit 210 and the battery pack 200 can be maintained. In addition, for example, by configuring two of the plurality of switch units 210 with the contactor 214, redundancy can be provided.

[0091] exist Figure 8In the example shown, six of the eight switching units 210 have a discharge FET and a charge FET, and two of the switching units 210 have a contactor 214. Alternatively, during charging, the management unit 110 sets the six switching units 210 to a charge state and turns on the contactors 214 of two of the switching units 210, thereby charging all of the plurality of battery packs 200. Alternatively, during discharging, the management unit 110 turns on the two contactors 214 and alternately sets the six switching units 210 to a discharge state. Alternatively, during the discharge, as described above, the management unit 110 sets one of the six switching units 210 to a discharge state, sets the next switching unit 210 to a discharge state, and sets one of the switching units 210 to a discharge state after a predetermined time has elapsed. In addition, the management unit 110 may alternately set the six switching units 210 to a discharge state so that they do not simultaneously become a discharge state.

[0092] Fig. 9 Another example of the structure of the plurality of switching units 210 is schematically shown. Fig. 9 As shown, the system 10 may also be configured such that a portion of the plurality of switching units 210 has a discharge FET and a charge FET, and another portion of the plurality of switching units 210 has: a contactor 214 connected to the bus 400; and a discharge FET and a charge FET connected in series between the contactor 214 and the battery pack 200.

[0093] Alternatively, the management unit 110 maintains the contactor 214 of another part of the plurality of switching units 210 in an open state while a predetermined condition is satisfied. The management unit 110 determines whether the predetermined condition is satisfied, for example, based on weather information of the area where the system 10 is located, which is received from the outside by the receiving unit 116. The weather information may indicate the current weather in various places. The weather information may indicate the forecast of the weather in various places. For example, while the system 10 is located in an area where lightning occurs, the management unit 110 maintains the contactor 214 in an open state. Alternatively, when the system 10 is not located in an area where lightning occurs, the management unit 110 sets the contactor 214 to an on state. Alternatively, when the contactor 214 is maintained in an OFF state, the management unit 110 may alternately set the plurality of switch units 210 having a portion of the discharge FET and the charge FET in the plurality of switch units 210 to the discharge state, or when the contactor 214 is set in an ON state, the management unit 110 may alternately set all of the plurality of switch units 210 to the discharge state. The lightning-generating area may be an area where lightning is currently occurring or an area where lightning is expected to occur.

[0094] exist Fig. 9In the example shown, the contactor 214 is disconnected in the area where lightning occurs. Therefore, even if lightning strikes, even if the FET of a part of the plurality of switching parts 210 fails and no current flows, the FET of another part of the plurality of switching parts 210 can be protected. Fig. 9 In the example shown, the contactor 214 is turned on in an area where lightning does not occur. Therefore, in general, in an area where lightning occurs, the discharge FET and the charging FET of the switching unit 210 composed of the contactor 214, the discharge FET and the charging FET can be protected. In areas other than the area where lightning occurs, switching is performed by the discharge FET and the charging FET instead of the contactor 214, which can improve the resistance to switching.

[0095] exist Fig. 9 In the example shown, six of the eight switching units 210 are composed of a discharge FET and a charge FET, and two of the switching units 210 are composed of a contactor 214, a discharge FET, and a charge FET. The management unit 110 may maintain the contactor 214 in the off state for the two switching units 210 while the system 10 is located in the area where lightning occurs, and may turn on the contactor 214 for the two switching units 210 when the system 10 is not located in the area where lightning occurs. Furthermore, the management unit 110 may alternately set all of the six switching units 210 to the discharge state when the system 10 is located in the area where lightning occurs, and may alternately set the eight switching units 210 to the discharge state when the system 10 is not located in the area where lightning occurs.

[0096] There are two types of contactors: one that is disconnected when a control current is applied and one that is connected when a control current is applied. Alternatively, the contactor 214 involved in this embodiment is of a type that is disconnected when a control current is applied. When the system 10 is located in an area where lightning occurs, the management unit 110 applies a control current to the contactors 214 of the two switching units 210 to disconnect them. Even if lightning strikes the system 10 and current no longer flows through the FETs 211 and 212 of the six switching units 210, the FETs 211 and 212 of the two switching units 210 can be protected. In addition, when the current system fails due to lightning and the supply of power stops, the control current to the contactor 214 stops, the contactor 214 is turned on, and the power from the two battery packs 200 connected to the two switching units 210 is supplied to the load 500, etc., so that at least the minimum function of the system 10 can be maintained.

[0097] The ratio of the switching unit 210 composed of the discharge FET and the charge FET to the switching unit 210 composed of the contactor 214, the discharge FET, and the charge FET may be any ratio. For example, one of the plurality of switching units 210 may be composed of the contactor 214, the discharge FET, and the charge FET, or two of the plurality of switching units 210 may be composed of the contactor 214, the discharge FET, and the charge FET.

[0098] In addition, all of the multiple switching units 210 may be composed of contactors 214, discharge FETs, and charge FETs. In this way, safety can be further improved. In this case, the management unit 110 may turn on only the contactors 214 of a portion of the multiple switching units 210 while the system 10 is located in an area where lightning occurs, and maintain the contactors 214 of the other switching units 210 in an open state. In order to maintain the function of the system 10 to a minimum, the management unit 110 may turn on only the necessary number of contactors 214 of the switching units 210, and maintain the contactors 214 of the other switching units 210 in an open state. Alternatively, all of the contactors 214 of the plurality of switching units 210 may be of a type that is disconnected when a control current is applied, or the management unit 110 may connect only the contactors 214 of a portion of the plurality of switching units 210 while the system 10 is located in an area where lightning occurs, and apply a control current to the contactors 214 of the other switching units 210 to maintain them in a disconnected state.

[0099] Fig.10 An example of the structure of the switching unit 210 composed of the contactor 214, the discharge FET, and the charge FET is schematically shown. Fig.10 As illustrated, the switch unit 210 may include: a contactor 214 connected to the bus 400; and a discharge FET and a charge FET connected in series between the contactor 214 and the battery pack 200. For example, the management unit 110 maintains the contactor 214 open while the system 10 is located in a lightning-generated area. Thus, even if lightning strikes the system 10, power can be prevented from flowing to the FET 211, the FET 212, and the battery pack 200, and the FET 211, the FET 212, and the battery pack 200 can be protected. The management unit 110 may also open the contactor 214 when a malfunction occurs in at least one of the FET 211 and the FET 212 for some reason. In the case where the FET 211 and the FET 212 are assumed to be in the mode C where the FET 211 and the FET 212 fail, if power flows through the FET 211 and the FET 212, heat is generated, and a fire may occur depending on the situation, but this can be prevented by opening the contactor 214.

[0100] In the above embodiment, the contactor 214 and the contactor 21 are described as being of a type that is opened when the control current is applied, but the present invention is not limited thereto. The contactor 214 may be of a type that is closed when the control current is applied.

[0101] Fig.11 An example of an aircraft 600 equipped with the system 10 is schematically shown. The aircraft 600 may be an example of an air vehicle. Fig.11 In FIG. 1 , battery packs 220 to 231 are illustrated as examples of the plurality of battery packs 200 . Fig.11 In the example shown, battery packs 220 to 224 are disposed in the left wing portion 622 of the wing portion 620 , battery packs 225 and 226 are disposed in the body 610 , and battery packs 227 to 231 are disposed in the right wing portion 624 of the wing portion 620 .

[0102] exist Fig.11 In the figure, the management device 100, the plurality of switching units 210, the plurality of power generation units 300, and the wiring of the battery packs 220 to 231 to the bus 400 are omitted. In addition, the description is mainly based on the case where all the plurality of switching units 210 are composed of discharge FETs and charge FETs.

[0103] The management device 100 is disposed, for example, in a body 610 of an aircraft 600. The power generation unit 300 is disposed, for example, on an upper surface of a wing 620. The battery packs 220 to 231 are connected in parallel with respect to the bus 400. The propeller 630 is an example of the load 500.

[0104] Here, the order in which the management unit 110 discharges the plurality of battery packs 200 two at a time is described. Alternatively, the management unit 110 repeats the following order: selects one from each of the groups 901 and 905 that are arranged symmetrically on the left and right and discharges it, selects one from each of the groups 902 and 904 and discharges it, and selects two from the group 903 and discharges it. The order of selecting one from each of the two groups that are arranged symmetrically on the left and right may be selected in a manner that is consistent in the front-to-back direction, or may be selected in a manner that is inconsistent in the front-to-back direction. For example, in the former case, the management unit 110 sequentially discharges the battery packs 220 and 229, the battery packs 221 and 230, the battery packs 222 and 231, sequentially discharges the battery packs 223 and 227, the battery packs 224 and 228, and discharges the battery packs 225 and 226.

[0105] When a part of the switching units 210 among the plurality of switching units 210 is constituted by the contactor 214 , for example, the switching unit 210 connected to the battery pack 225 and the battery pack 226 may be constituted by the contactor 214 .

[0106] Fig.12 Another example of an aircraft 600 equipped with the system 10 is schematically shown. Fig.11 Different points are explained. Fig.12 In the example shown, the battery packs 220 to 225 are arranged on the left wing portion 622 of the wing portion 620 , and the battery packs 226 to 231 are arranged on the right wing portion 624 of the wing portion 620 .

[0107] Alternatively, the management unit 110 repeats the following sequence: selects one from each of the groups 901 and 904 that are symmetrically arranged on the left and right and discharges it, and selects one from each of the groups 902 and 903 and discharges it. The sequence of selecting one from each of the two groups that are symmetrically arranged on the left and right may be selected in a manner that is consistent in the front-to-back direction, or may be selected in a manner that is inconsistent in the front-to-back direction. For example, in the former case, the management unit 110 sequentially discharges the battery packs 220 and 229, the battery packs 221 and 230, and the battery packs 222 and 231, and sequentially discharges the battery packs 223 and 226, the battery packs 224 and 227, and the battery packs 225 and 228.

[0108] Fig.13 Another example of an aircraft 600 equipped with the system 10 is schematically shown. Fig.11 Different points are explained. Fig.13 In the illustrated example, battery packs 220 to 226 are arranged on the left side of aircraft 600 , battery packs 227 to 240 are arranged in the center of aircraft 600 , and battery packs 231 to 237 are arranged on the right side of aircraft 600 .

[0109] Alternatively, the management unit 110 repeats the following sequence: selects one from each of the groups 901 and 905 that are symmetrically arranged on the left and right and discharges it, selects one from each of the groups 902 and 904 and discharges it, and selects two from the group 903 and discharges it. The sequence of selecting one from each of the two groups that are symmetrically arranged on the left and right may be selected in a manner that is consistent in the front-to-back direction, or may be selected in a manner that is inconsistent in the front-to-back direction. For example, in the former case, the management unit 110 sequentially discharges the battery pack 220 and the battery pack 236, the battery pack 221 and the battery pack 237, sequentially discharges the battery pack 222 and the battery pack 231, the battery pack 223 and the battery pack 232, the battery pack 224 and the battery pack 233, the battery pack 225 and the battery pack 234, the battery pack 226 and the battery pack 235, and sequentially discharges the battery pack 227 and the battery pack 228, the battery pack 229 and the battery pack 230.

[0110] Fig.14 Another example of an aircraft 600 equipped with the system 10 is schematically shown. Fig.11 Different points are explained. Fig.14 In the example shown, battery packs 220 to 223 , battery packs 228 , and battery pack 229 are arranged in the left wing portion 622 of the wing 620 , battery packs 224 to 227 are arranged in the center portion of the aircraft 600 , and battery packs 230 to 235 are arranged in the right wing portion 624 of the wing 620 .

[0111] Alternatively, the management unit 110 repeats the following sequence: selects one from each of the groups 901 and 905 that are symmetrically arranged on the left and right and discharges it, selects one from each of the groups 902 and 904 and discharges it, and selects two from the group 903 and discharges it. The sequence of selecting one from each of the two groups that are symmetrically arranged on the left and right may be selected in a manner that is consistent in the front-to-back direction, or may be selected in a manner that is inconsistent in the front-to-back direction. For example, in the former case, the management unit 110 sequentially discharges the battery pack 220 and the battery pack 234, the battery pack 221 and the battery pack 235, sequentially discharges the battery pack 222 and the battery pack 232, the battery pack 223 and the battery pack 233, and sequentially discharges the battery pack 229 and the battery pack 231, the battery pack 228 and the battery pack 230, the battery pack 226 and the battery pack 227, and the battery pack 224 and the battery pack 225.

[0112] Fig.15 An example of a HAPS 700 equipped with the system 10 is schematically shown. The HAPS 700 is an air vehicle that provides wireless communication services to user terminals 30 within a communication area 704 formed by irradiating a beam 702 onto the ground.

[0113] HAPS 700 includes a body 710 , a center section 720 , a propeller 730 , a pod 740 , and a solar panel 750 . Body 710 includes a wing section 712 . Wing section 712 includes a left wing section 714 and a right wing section 716 .

[0114] Inside the wing 712, a plurality of battery packs 200 connected in parallel are arranged. Alternatively, the plurality of battery packs 200 on the left side of the plurality of battery packs 200 may be arranged on the left wing 714, and the plurality of battery packs 200 on the right side may be arranged on the right wing 716. Alternatively, the plurality of battery packs 200 may be connected to the bus 400 via a plurality of switching units 210. Alternatively, the solar panel 750 may be connected to the bus 400 via the MPPT 320. The power discharged by the plurality of battery packs 200 is utilized by the various structures possessed by the HAPS 700. For example, the power discharged by the plurality of battery packs 200 is utilized by the motor of the propeller 730. The motor of the propeller 730 may be an example of the load 500.

[0115] The flight control unit 722 and the communication control unit 724 and the management device 100 (not shown) are arranged in the center unit 720. The flight control unit 722 controls the flight of the HAPS 700 using the power discharged from the plurality of battery packs 200. The communication control unit 724 controls the communication of the HAPS 700 using the power discharged from the plurality of battery packs 200.

[0116] The flight control unit 722 controls the flight of the HAPS 700 by, for example, controlling the rotation of the propeller 730. Alternatively, the flight control unit 722 may control the flight of the HAPS 700 by changing the angles of flaps and elevators (not shown). Alternatively, the flight control unit 722 may include various sensors such as a positioning sensor such as a GPS sensor, a gyro sensor, and an acceleration sensor to manage the position, movement direction, and movement speed of the HAPS 700.

[0117] The communication control unit 724 forms a communication area 704 on the ground using an SL (Service Link) antenna. The communication control unit 724 forms a service link with the user terminal 30 on the ground using the SL antenna. The SL antenna may be a multi-beam antenna. The communication area 704 may be a multi-cell.

[0118] The communication control unit 724 may use an FL (Feeder Link) antenna to form a feeder link with the gateway 40 on the ground. The communication control unit 724 may access the network 20 via the gateway 40 .

[0119] The communication control unit 724 may communicate with the communication satellite 50 using a satellite communication antenna. The communication control unit 724 may access the network 20 via the communication satellite 50 and the satellite communication station 60.

[0120] The user terminal 30 can be any communication terminal as long as it can communicate with the HAPS 700. For example, the user terminal 30 is a mobile phone such as a smartphone. The user terminal 30 can be a tablet terminal and a PC (Personal Computer). The user terminal 30 can be a so-called IoT (Internet of Thing) device. The user terminal 30 can include any device that complies with the so-called IoE (Internet of Everything).

[0121] HAPS 700 relays the communication between the network 20 and the user terminal 30 via, for example, a feeder link or a communication satellite 50 and a service link. Alternatively, HAPS 700 may provide wireless communication services to the user terminal 30 by relaying the communication between the user terminal 30 and the network 20.

[0122] The network 20 includes a mobile communication network. The mobile communication network may comply with any of the communication methods after the 3G (3rd Generation), LTE (Long Term Evolution), 5G (5th Generation), and 6G (6th Generation). The network 20 may include the Internet.

[0123] HAPS 700 transmits data received from user terminal 30 in communication area 704 to network 20 . When HAPS 700 receives data destined for user terminal 30 in communication area 704 via network 20 , it transmits the data to user terminal 30 .

[0124] HAPS 700 maintains a communication area 704 in a specific area on the ground while patrolling a predetermined flight path in the stratosphere, for example. HAPS 700 stores the power generated by solar panels 750 in multiple battery packs 200 during the day, and uses the power of multiple battery packs 200 to maintain flight in the stratosphere at night. HAPS 700 charges multiple battery packs 200 during the day, ascends to accumulate potential energy, and slowly descends at night, and appropriately uses the power of the battery packs 200 to operate the propellers 730, etc., to maintain flight in the stratosphere.

[0125] The management device 800 manages a plurality of HAPSs 700. The management device 800 may communicate with the HAPSs 700 via the network 20 and the gateway 40. The management device 800 may communicate with the HAPSs 700 via the network 20, the satellite communication station 60, and the communication satellite 50.

[0126] The management device 800 controls the HAPS 700 by sending instructions. Alternatively, the management device 800 may cause the HAPS 700 to orbit over the target area in order to cover the target area on the ground through the communication area 704. For example, the HAPS 700 flies in a circular orbit over the target area, and maintains the feeder link with the gateway 40 by adjusting the pointing direction of the FL antenna, and maintains the coverage of the target area by the communication area 704 by adjusting the pointing direction of the SL antenna.

[0127] As described above, the management unit 110 of the management device 100 manages the plurality of battery packs 200 in such a manner that the plurality of battery packs 200 are alternately discharged so that the difference between the voltage of the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage among the plurality of battery packs 200 is not greater than the voltage threshold. Thus, as described above, the degradation of the plurality of battery packs 200 can be reduced, and the period during which the HAPS 700 can maintain the flight in the stratosphere can be extended.

[0128] Alternatively, the management unit 110 manages the HAPS 700 to ascend using the power generated by the solar panel 750 so that the charging rate of the plurality of battery packs 200 charged using the power generated by the solar panel 750 does not exceed the charging rate threshold. For example, the management unit 110 controls the propeller 730, flaps, and elevators to be supplied with the power generated by the solar panel 750, and the flight control unit 722 controls the propeller 730, flaps, and elevators to ascend. By converting the surplus power into potential energy, the surplus power can be used without waste.

[0129] Alternatively, the management unit 110 manages in such a manner that, when the discharge rate of a battery pack 200 being discharged among the plurality of battery packs 200 is slower than the discharge rate threshold value for a predetermined period of time, the load 500 is raised by the power of the battery pack 200 being discharged. For example, the management unit 110 controls so that the power of the battery pack 200 being discharged is supplied to the propeller 730, flaps, and elevator, and the flight control unit 722 controls the propeller 730, flaps, and elevator so that the HAPS 700 rises. By setting the discharge rate of the battery pack 200 being discharged to a preferred discharge rate and converting the power into energy, the power can be used without waste.

[0130] Alternatively, the management unit 110 manages the plurality of battery packs 200 in such a manner that, in a time period determined as daytime, the plurality of battery packs 200 are alternately discharged so that the voltage difference between the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage is not greater than a first voltage threshold, and in a time period determined as nighttime, the plurality of battery packs 200 are alternately discharged so that the voltage difference between the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage is not greater than a second voltage threshold that is greater than the first voltage threshold. Since the solar panel 750 does not charge the plurality of battery packs 200 at night, even if the voltage difference between the battery pack 200 with the largest voltage and the battery pack 200 with the smallest voltage is greater than during the daytime, there is less of a problem. By setting the voltage threshold used at night to the second voltage threshold that is greater than the first voltage threshold used during the daytime, the number of switching times of the battery pack 200 to be discharged can be reduced.

[0131] Fig.16 An example of the hardware structure of a computer 1200 that functions as the management device 100 is schematically shown. The program installed in the computer 1200 can make the computer 1200 function as one or more "parts" of the device involved in the above-mentioned embodiment, or can make the computer 1200 perform operations associated with the device involved in the above-mentioned embodiment or the one or more "parts", and / or can make the computer 1200 perform the process involved in the above-mentioned embodiment or the stage of the process. Such a program can be executed by the CPU 1212 to make the computer 1200 perform specific operations associated with part or all of the blocks in the flowcharts and block diagrams described in this specification.

[0132] The computer 1200 of this embodiment includes a CPU 1212, a RAM 1214, and a graphics controller 1216, which are connected to each other through a host controller 1210. The computer 1200 also includes a communication interface 1222, a storage device 1224, and input / output units such as a DVD drive and an IC card drive, which are connected to the host controller 1210 via an input / output controller 1220. The storage device 1224 may be a hard disk drive, a solid state drive, etc. The computer 1200 also includes a ROM 1230 and a conventional input / output unit such as a keyboard, which are connected to the input / output controller 1220 via an input / output chip 1240.

[0133] The CPU 1212 controls each unit by operating according to the program stored in the ROM 1230 and the RAM 1214. The graphic controller 1216 acquires the image data generated by the CPU 1212 from a frame buffer or the like provided in the RAM 1214 or from itself, and displays the image data on the display device 1218.

[0134] The communication interface 1222 communicates with other electronic devices via a network. The storage device 1224 stores programs and data used by the CPU 1212 in the computer 1200. The IC card driver reads programs and data from an IC card and / or writes programs and data to an IC card.

[0135] The ROM 1230 holds therein a boot program or the like executed by the computer 1200 upon activation and / or a program depending on the hardware of the computer 1200. The input-output chip 1240 can also connect various input-output units to the input-output controller 1220 via a USB port, a parallel port, a serial port, a keyboard port, a mouse port, and the like.

[0136] The program is provided by a computer-readable storage medium such as a DVD-ROM or an IC card. The program is read from the computer-readable storage medium, installed in the storage device 1224, RAM 1214, or ROM 1230, which is also an example of a computer-readable storage medium, and executed by the CPU 1212. The information processing described in these programs is read by the computer 1200, and the cooperation between the program and the various types of hardware resources described above occurs. The device or method can be configured by implementing the operation or processing of information according to the use of the computer 1200.

[0137] For example, when the computer 1200 communicates with an external device, the CPU 1212 executes a communication program loaded into the RAM 1214, and instructs the communication interface 1222 to perform a communication process based on the process described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads the transmission data stored in the transmission buffer area provided in the RAM 1214, the storage device 1224, a DVD-ROM, or an IC card, and transmits the read transmission data to the network, or writes the reception data received from the network to the reception buffer area provided on the recording medium.

[0138] Alternatively, the CPU 1212 may read all or a necessary portion of a file or database stored in an external recording medium such as the storage device 1224, a DVD drive (DVD-ROM), an IC card, etc., into the RAM 1214, and perform various types of processing on the data in the RAM 1214. The CPU 1212 may then write the processed data back to the external recording medium.

[0139] Various types of information such as various types of programs, data, tables, and databases can be stored in the recording medium and subjected to information processing. Alternatively, the CPU 1212 performs various types of processing including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information retrieval and replacement, etc., which are recorded in various places of the present disclosure and specified by the instruction sequence of the program, on the data read from the RAM 1214, and writes the result back to the RAM 1214. In addition, the CPU 1212 may retrieve information from files, databases, etc. in the recording medium. For example, in the case where a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, the CPU 1212 may retrieve an entry consistent with the condition specifying the attribute value of the first attribute from the plurality of entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0140] The program or software module described above may be stored in a computer-readable storage medium on or near the computer 1200. In addition, a recording medium such as a hard disk or RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, thereby providing the program to the computer 1200 via the network.

[0141] The boxes in the flowcharts and block diagrams in this embodiment may represent the stages of the process of performing an operation or the "parts" of the device that undertakes the task of performing an operation. Specific stages and "parts" may be implemented by dedicated circuits, programmable circuits supplied together with computer-readable instructions stored on a computer-readable storage medium, and / or processors supplied together with computer-readable instructions stored on a computer-readable storage medium. Dedicated circuits may include digital and / or analog hardware circuits, and may also include integrated circuits (ICs) and / or discrete circuits. Programmable circuits may include, for example, field programmable gate arrays (FPGAs) and programmable logic arrays (PLAs), which include logical AND, logical OR, logical XOR, logical ANDN, logical ORN, and other logical operations, triggers, registers, and memory elements that are reconfigurable hardware circuits.

[0142] A computer-readable storage medium may include any tangible device capable of storing instructions to be executed by an appropriate device, with the result that a computer-readable storage medium having instructions stored therein has a product containing instructions executable to produce a unit for performing the operations specified in a flowchart or block diagram. Examples of computer-readable storage media include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, etc. More specific examples of computer-readable storage media include floppy (registered trademark) disks, magnetic disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), electrically erasable programmable read-only memories (EEPROM), static random access memories (SRAM), compact disk read-only memories (CD-ROM), digital versatile disks (DVD), Blu-ray (registered trademark) disks, memory sticks, integrated circuit cards, etc.

[0143] Computer readable instructions may include any of assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state setting data, or source code or object code described in any combination of one or more programming languages ​​including object-oriented programming languages ​​such as Smalltalk (registered trademark), JAVA (registered trademark), C++, and existing procedural programming languages ​​such as the "C" programming language or similar programming languages.

[0144] The computer-readable instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, or a programmable circuit locally or via a wide area network (WAN) such as a local area network (LAN), the Internet, etc., so that the processor of the general-purpose computer, the special-purpose computer, or other programmable data processing device or the programmable circuit executes the computer-readable instructions to generate a unit for applying the operations specified in the flowchart or block diagram. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, etc.

[0145] The present invention has been described above using the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various changes or improvements can be made to the above embodiments. According to the description of the claims, the method to which such changes or improvements are made can also be included in the technical scope of the present invention.

[0146] It should be noted that the execution order of each process such as actions, sequences, steps and stages in the apparatus, system, program and method shown in the claims, specifications and drawings can be implemented in any order unless it is specifically stated that "before", "prior to", etc., and the output of the previous process is not used in the subsequent process. Even if the action flow in the claims, specifications and drawings is described using "first", "next", etc. for convenience, it does not mean that it must be implemented in this order.

[0147] By using the present invention, it is possible to suppress the degradation caused by the increase in the discharge rate of the battery and increase the life of the battery, thereby contributing to Goal 7 of the Sustainable Development Goals (SDGs) "saving energy and making it clean" or Goal 13 "taking concrete measures to combat climate change".

[0148] Description of Reference Numerals

[0149] 10…system; 20…network; 30…user terminal; 40…gateway; 50…communication satellite; 60…satellite communication station; 100…management device; 110…management unit; 112…group association information acquisition unit; 114…estimation unit; 116…receiving unit; 200…battery pack; 202…single battery; 210…switching unit; 211…FET; 212…FET; 214…contactor; 220 , 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233, 234, 235, 236, 237…battery pack; 300…power generation unit; 310…solar cell; 320…MPPT; 400…bus; 500…load; 510…controller; 600…aircraft; 610…aircraft body; 620 ...wing; 622...left wing; 624...right wing; 630...propeller; 700...HAPS; 702...beam; 704...communication area; 710...fuselage; 712...wing; 714...left wing; 716...right wing; 720...central part; 722...flight control unit; 724...communication control unit; 730...propeller; 740...pod; 750...solar panel; 800...management device; 901, 902, 903, 904, 905...group; 1200...computer; 1210...host controller; 1212...CPU; 1214...RAM; 1216...graphics controller; 1218...display device; 1220...input and output controller; 1222...communication interface; 1224...storage device; 1230...ROM; 1240...input and output chip.

Claims

1. A system, characterized in that: have: A plurality of switching units are connected in parallel with respect to a bus connected with the power generation unit and the load, and respectively switch on and off the connection of the battery group with respect to the bus; The plurality of battery packs are connected to the plurality of switching parts respectively; as well as a management unit that manages the plurality of switching units in such a manner that the plurality of battery packs are alternately discharged so that the discharge rate of each of the plurality of battery packs becomes higher than when all of the plurality of battery packs are discharged, At least one of the plurality of switching units has a discharge FET and a charge FET, and the discharge FET and the charge FET can be switched between a discharge state, a charge state, and a cut-off state. The discharge state is a state in which current flows from the connected battery pack to the bus, the charge state is a state in which current flows from the bus to the battery pack, and the cut-off state is a state in which current does not flow between the bus and the battery pack.

2. The system according to claim 1, characterized in that A part of the plurality of switching parts includes the discharge FET and the charge FET, and another part of the plurality of switching parts includes: a contactor connected to the bus; and the discharge FET and the charge FET connected in series between the contactor and the battery pack.

3. The system according to claim 2, characterized in that The management unit maintains the contactors of the other part of the plurality of switching units in an open state while a predetermined condition is satisfied.

4. The system according to claim 3, characterized in that The management unit maintains the contactors of the other part of the plurality of switching units in an open state while the system is located in an area where lightning occurs.

5. The system according to claim 3 or 4, characterized in that: When a malfunction occurs in at least one of the discharge FET and the charge FET of the other part of the plurality of switch parts, the management part maintains the contactor of the other part in an open state.

6. The system according to any one of claims 3 to 5, characterized in that The contactor is of the type that opens when a control current is applied, The management unit applies the control current to the contactor while the predetermined condition is satisfied.

7. The system according to claim 1, characterized in that Some of the plurality of switching units include the discharge FET and the charge FET, and another portion of the plurality of switching units includes a contactor that switches on and off current between the connected battery pack and the bus line.

8. The system according to claim 7, characterized in that During charging, the management unit sets the part of the multiple switching parts to the charging state and turns on the contactors of the other part of the multiple switching parts. During discharging, the management unit turns on the contactors of the other part of the multiple switching parts and alternately sets the part of the multiple switching parts to the discharging state.

9. The system according to claim 8, characterized in that During the discharge, the management unit alternately sets the part of the plurality of switch units to the discharge state so that all of the switch units are not simultaneously set to the discharge state.

10. The system according to claim 1, characterized in that All of the plurality of switching units include the discharge FET and the charge FET.

11. The system according to claim 1, characterized in that Each of the plurality of switching units includes a contactor connected to the bus line, and the discharge FET and the charge FET connected in series between the contactor and the battery pack.

12. The system according to claim 11, characterized in that The management unit maintains the contactor of a part of the plurality of switching units in an open state while a predetermined condition is satisfied.

13. The system according to claim 12, characterized in that The management unit turns on only the contactors of the part of the switching units among the plurality of switching units and maintains the contactors of the other switching units among the plurality of switching units in an off state while the system is located in an area where lightning occurs.

14. The system according to claim 13, characterized in that The contactors of the plurality of switching units are of a type that opens when a control current is applied, The management unit applies the control current to the contactor of the other switching unit among the plurality of switching units while the system is located in an area where lightning occurs.

15. The system according to any one of claims 1 to 14, characterized in that The management unit controls the plurality of switching units so that the plurality of battery groups are alternately discharged so that a voltage difference between a battery group having a maximum voltage and a battery group having a minimum voltage among the plurality of battery groups is not greater than a voltage threshold.

16. The system according to any one of claims 1 to 15, characterized in that The management unit controls the plurality of switching units so that the plurality of battery packs are simultaneously charged with the electric power generated by the power generation unit.

17. The system according to any one of claims 1 to 16, characterized in that The system is mounted on a flying object. The plurality of battery packs are arranged on the wings of the flying object. The power generation unit performs solar power generation, The load is a motor that rotates a propeller of the flying object.

18. The system according to claim 17, characterized in that The system includes the flying object.

19. The system according to claim 18, characterized in that The flying object has a communication control unit. The communication control unit provides a wireless communication service to user terminals within a communication area formed by irradiating a beam toward the ground, using electric power discharged from the plurality of battery packs.

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