Power supply and demand system, battery control system, battery control method

Abstract

To extend the life of the entire battery system.SOLUTION: A battery control system includes a low-capacity battery setting unit 23 that sets a low-capacity battery to reduce the frequency of use on the basis of a deterioration evaluation value related to the full charge capacity of each storage battery at the start of a battery system, an initial power command setting unit 24 that sets an individual power command for a storage battery so as to reduce the frequency of use of the low-capacity battery compared to an operational battery which is a storage battery other than the low-capacity batteries, and a setting cancellation unit 25 that acquires a deterioration evaluation value of each storage battery after the low-capacity battery has been set and cancels the low-capacity battery setting when the acquired deterioration evaluation value of each storage battery satisfies a predetermined cancellation condition.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a power supply and demand system, a battery control system, a battery control method, and a battery control program. [Background technology]

[0002] There are known techniques for measuring the state of charge (SOC) and state of health (SOH) to grasp the state of a storage battery. For example, Patent Document 1 discloses a battery state of charge calculation method for determining a linear approximation of the current-voltage characteristics of a battery from the battery current and battery voltage, and estimating the state of charge and / or state of deterioration of the battery using the slope and intercept of the equation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-345135 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the invention of Patent Document 1, although the battery characteristics (battery performance level, SOH) are estimated and the life of the battery (storage battery) is judged, no consideration has been given to the operation of the battery system when there is variation in the battery characteristics of the multiple batteries. When there is variation in the battery characteristics of the multiple batteries included in the battery system, it is difficult to extend the life of the entire battery system.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a battery control system, a power supply and demand system, a battery control method, and a battery control program that can extend the life of the entire battery system. [Means for solving the problem]

[0006] One aspect of the present disclosure is a battery control system applicable to a battery system having a plurality of storage batteries, the battery control system comprising: a low-capacity battery setting unit that sets a low-capacity battery to reduce the frequency of use based on a deterioration evaluation value related to the full charge capacity of each of the storage batteries at the start of the battery system; an initial power command setting unit that sets individual power commands for the storage batteries so as to reduce the frequency of use of the low-capacity battery compared to operational batteries which are storage batteries other than the low-capacity batteries; and a setting cancellation unit that acquires a deterioration evaluation value of each of the storage batteries after the low-capacity batteries have been set, and cancels the setting of the low-capacity battery when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined cancellation condition.

[0007] One aspect of the present disclosure is an electric power supply and demand system including a battery system including a plurality of storage batteries and the battery control system.

[0008] One aspect of the present disclosure is a battery control method applied to a battery system including a plurality of storage batteries, the battery control method being executed by a computer to perform the following steps at the start-up of the battery system: setting a low-capacity battery to reduce the frequency of use based on a deterioration evaluation value related to the full charge capacity of each of the storage batteries; setting individual power commands for the storage batteries so as to reduce the frequency of use of the low-capacity battery compared to operational batteries which are storage batteries other than the low-capacity battery; acquiring a deterioration evaluation value of each of the storage batteries after the low-capacity battery has been set, and canceling the setting of the low-capacity battery when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined cancellation condition.

[0009] One aspect of the present disclosure is a program for causing a computer to function as the battery control system. Effect of the Invention

[0010] The life of the entire battery system can be extended. [Brief description of the drawings]

[0011] [Figure 1] 1 is a diagram showing a schematic configuration of an electricity supply and demand system according to a first embodiment of the present disclosure. [Diagram 2] 1 is a diagram illustrating an example of a hardware configuration of a battery control system according to a first embodiment of the present disclosure. [Diagram 3] 2 is a functional configuration diagram showing an example of functions of the battery control system according to the first embodiment of the present disclosure. FIG. [Figure 4] 2 is a functional configuration diagram showing an example of functions of an initial operation control unit according to the first embodiment of the present disclosure. FIG. [Diagram 5] 10 is a diagram showing a comparison of an example of the transition of a representative value of the full charge capacity of a low-capacity battery and a representative value of the full charge capacity of an operational battery when an initial operation control according to the first embodiment of the present disclosure is performed. FIG. [Figure 6] 2 is a functional configuration diagram showing an example of functions of a mid-term operation control unit according to the first embodiment of the present disclosure. FIG. [Figure 7] FIG. 13 is a diagram showing an example of a sharing adjustment rate of a storage battery. [Figure 8] FIG. 7 is a diagram showing examples of individual power commands when the sharing adjustment rate is set to 0.8 and 1.2 for comparison. [Figure 9] FIG. 7 is a diagram showing, for comparison, examples of charge and discharge currents when the sharing adjustment ratios are set to 0.8 and 1.2, respectively. [Figure 10] FIG. 7 shows examples of SOC when the sharing adjustment rate is set to 0.8 and 1.2 for comparison. [Figure 11] 1 is a functional configuration diagram showing an example of functions of a post-operation control unit according to the first embodiment of the present disclosure. FIG. [Figure 12] 1 is a diagram for explaining the occurrence of variation in the central value of the charging rate among storage batteries over time. FIG. [Figure 13] 4 is a flowchart showing an example of a procedure of an initial operation control method executed by the battery control system according to the first embodiment of the present disclosure. [Figure 14]4 is a flowchart showing an example of a procedure of a mid-term operation control method executed by the battery control system according to the first embodiment of the present disclosure. [Figure 15] 4 is a flowchart showing an example of the procedure of a post-operation control method executed by the battery control system according to the first embodiment of the present disclosure. [Figure 16] 11A to 11C are diagrams for explaining the effect of a post-operation control unit according to the first embodiment of the present disclosure. [Figure 17] FIG. 10 is a diagram for explaining the tendency for the center of SOC of the entire battery system to shift over time. [Figure 18] A functional configuration diagram showing an example of functions provided in a post-operation control unit according to the second embodiment of the present disclosure. [Figure 19] A functional configuration diagram showing a modified example of the functions of the post-operation control unit according to the second embodiment of the present disclosure. [Figure 20] FIG. 13 is a diagram showing a schematic configuration of an electricity supply and demand system according to a third embodiment of the present disclosure. [Figure 21] FIG. 11 is a functional configuration diagram showing an example of functions provided in a mid-term operation control unit of a battery control system according to a third embodiment of the present disclosure. [Figure 22] FIG. 13 is a diagram illustrating a relationship between an individual power command and a bus voltage of a DC link according to a third embodiment of the present disclosure. [Diagram 23] 11 is a diagram showing an example of the relationship between the slope of storage batteries with different SOH and individual power commands. FIG. [Figure 24] FIG. 11 is a functional configuration diagram showing an example of functions provided in a post-operation control unit of a battery control system according to a third embodiment of the present disclosure. [Diagram 25] 10 is a diagram for explaining individual offset power when a battery system is connected to a DC link. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] [First embodiment] Hereinafter, a power supply and demand system, a battery control system, a battery control method, and a battery control program according to a first embodiment of the present disclosure will be described with reference to the drawings. 1 is a diagram showing a schematic configuration of an electricity supply and demand system 100 according to a first embodiment of the present disclosure. As shown in FIG 1, the electricity supply and demand system 100 includes a battery system (ESS: Energy Storage System) 1 and a battery control system 10.

[0013] The battery system 1 is connected to a power grid 2 via a substation 3, and supplies and demands electric power to and from the power grid 2. The substation 3 and the battery system 1 are connected by an AC link 4. The battery system 1 includes a plurality of storage batteries 5 (5a to 5d). FIG. 1 illustrates an example in which four storage batteries 5 are included, but the number of storage batteries 5 is not limited. Hereinafter, when it is necessary to distinguish between the storage batteries 5a, 5b, etc., they will be referred to as storage batteries 5a, 5b, and when it is not necessary to distinguish between them, they will be simply referred to as storage batteries 5. Other configurations will be treated in the same manner.

[0014] Each storage battery 5 is chargeable and dischargeable, and is configured, for example, as a battery string in which a plurality of unit batteries (cells) are connected in series. Alternatively, a configuration in which a plurality of battery strings are connected in parallel may be used. Also, each storage battery 5 may include a measurement unit (not shown) that measures various data (battery information) such as voltage value, current value, and temperature, and a battery management unit (BMU: Battery Management Unit) (not shown) that monitors the state of the storage battery 5 based on the measurement data. The configuration of the storage battery 5 may be any known technology and is not particularly limited.

[0015] Each storage battery 5 is connected to the AC link 4 via a power converter 7 (7a to 7d). The power converter 7 is, for example, an AC / DC converter. The power converter 7 controls the charging and discharging of the storage battery 5 by, for example, being driven based on an individual power command given from the battery control system 10. Specifically, the power converter 7a controls the charging and discharging of the storage battery 5a, the power converter 7b controls the charging and discharging of the storage battery 5b, the power converter 7c controls the charging and discharging of the storage battery 5c, and the power converter 7d controls the charging and discharging of the storage battery 5d. During charging, the power converter 7 converts AC power from the power system into DC power and outputs it to the storage battery 5, and during discharging, the power converter 7 converts DC power from the storage battery 5 into AC power and supplies it to the power system 2.

[0016] The battery control system 10 is a control system that controls the battery system 1. The battery control system 10 is connected to the battery system 1 via, for example, a communication network, and is configured to be able to send and receive information. The battery control system 10 may be a cloud server, or may be a local system installed at the location where the battery system 1 is installed. The battery control system 10 is also connected to a grid monitoring system 6 via a communication network. The grid monitoring system 6 is, for example, a central power supply command center of a power company or a higher-level energy management system (EMS), and determines a system power request to be made to the battery system 1 and transmits this to the battery control system 10.

[0017] Next, the battery control system 10 according to this embodiment will be described. Fig. 2 is a diagram showing an example of a hardware configuration of the battery control system 10. As shown in Fig. 2, the battery control system 10 is a computer and includes, for example, a CPU (Central Processing Unit: processor) 11, a main memory 12, a secondary storage 13, a communication interface 14, etc. The battery control system 10 may also include an input device 15 that accepts input from a user, a display 16, etc.

[0018] The main memory device 12 is composed of writable memory such as a cache memory or a RAM (Random Access Memory), and is used as a working area for reading out the execution program of the CPU 11, writing processing data by the execution program, and the like. The secondary storage device 13 is a non-transitory computer readable storage medium. Examples of the secondary storage device 13 include a magnetic disk such as a hard disk drive (HDD), a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory such as a solid state drive (SSD), and the like.

[0019] 3 is a functional configuration diagram showing an example of functions of the battery control system 10 according to this embodiment. The battery control system 10 charges and discharges the battery system 1 by employing different control methods depending on the operation phase (e.g., early, middle, or late) of the battery system. Specifically, the battery control system 10 includes an early operation control unit 20, a mid-operation control unit 30, a late operation control unit 40, and a control switching unit 50, as illustrated in FIG. The early operation control unit 20 performs early operation control in the early operation of the battery system 1. The mid-operation control unit 30 performs mid-operation control in the mid-operation of the battery system 1. The late operation control unit 40 performs late operation control in the late operation of the battery system 1. The early operation control unit 20, the mid-operation control unit 30, and the late operation control unit 40 will be described in detail later. The control switching unit 50 has switching conditions (cancellation conditions) for switching from early operation control to mid-operation control, and switching conditions (late operation conditions) for switching from mid-operation control to late operation control, and switches control when these switching conditions are met.

[0020] A series of processes for realizing various functions described below is stored in the secondary storage device 13 (see FIG. 2) in the form of a program (e.g., a battery control program), for example, and the CPU 11 reads this program into the main storage device 12 and executes information processing and arithmetic processing to realize various functions. Note that the program may be pre-installed in the secondary storage device 13, provided in a state stored in another computer-readable storage medium, or distributed via wired or wireless communication means. Examples of computer-readable storage media include magnetic disks, magneto-optical disks, CD-ROMs, DVD-ROMs, and semiconductor memories.

[0021] [Operation Initial Control Unit 20] 4 is a functional configuration diagram showing an example of functions of the initial operation control unit 20 according to this embodiment. As shown in FIG. 4, the initial operation control unit 20 includes, for example, a degradation state evaluation unit 21, a storage unit 22, a low-capacity battery setting unit 23, an initial power command setting unit 24, and a setting cancellation unit 25. The degradation state evaluation unit 21 acquires a degradation evaluation value related to the full charge capacity of each of the storage batteries 5a to 5d. For example, the degradation state evaluation unit 21 performs degradation state evaluation to acquire a degradation evaluation value when a preset start condition is satisfied. Examples of the start condition include the first start of the battery system 1, when a predetermined period has passed since the previous degradation state evaluation, when the cumulative operating time since the previous degradation state evaluation reaches a predetermined time, when a command to start the degradation state evaluation is input by a user, etc. The start condition may be set as a combination of these. Also, the cycle of the degradation state evaluation may be set to be shorter as the degradation evaluation value decreases.

[0022] An example of the degradation evaluation value is the SOH. The SOH is the ratio of the latest (current) full charge capacity to the initial full charge capacity (capacity of a battery that is not degraded). In other words, the SOH is a value obtained by normalizing the latest (current) full charge capacity [Ah] by a common battery capacity [Ah] (for example, the maximum full charge capacity at the time of battery manufacture, etc.). The degradation state evaluation unit 21 calculates the latest full charge capacity (Ah) by integrating the current value when the storage battery 5 is changed from a fully charged state to a lower limit charge state, or from the lower limit charge state to a fully charged state. In addition, in the process of calculating the latest full charge capacity, correction may be performed based on differences in test conditions (rate, temperature, etc.). The degradation state evaluation unit 21 calculates degradation evaluation values ​​(e.g., SOH) for all the storage batteries 5a-5d using the acquired latest full charge capacity (Ah), and stores battery evaluation information in which the identification information and the degradation evaluation value of each storage battery 5 are associated with each other in the memory unit 22. The battery evaluation information may also include time information, battery information of each storage battery 5a-5d acquired from the battery system 1, and the like. The deterioration evaluation value is not limited to the SOH as long as it is an evaluation value related to the full charge capacity of each of the storage batteries 5a to 5d. For example, a known evaluation value for evaluating the deterioration state of the storage battery may be used, and as one example, the full charge capacity (Ah) of each storage battery 5 may be used.

[0023] The low-capacity battery setting unit 23 sets a low-capacity battery to be used less frequently based on the deterioration evaluation value (e.g., SOH) of each of the storage batteries 5a-5d acquired by the deterioration state evaluation unit 21 at the start of the battery system 1. For example, the low-capacity battery setting unit 23 acquires the deterioration evaluation value of each of the storage batteries 5a-5d from the storage unit 22 at the start of the battery system 1, identifies the maximum value and the minimum value from among the acquired deterioration evaluation values, and calculates the difference between them. If the difference is greater than a preset threshold value, the storage battery 5 having the minimum deterioration evaluation value is set as a low-capacity battery. The number of storage batteries to be set as low-capacity batteries is not limited. For example, if the battery system 1 has a surplus battery capacity, multiple storage batteries may be set as low-capacity batteries.

[0024] The initial power command setting unit 24 sets an individual power command for each storage battery 5 based on, for example, a control algorithm at the beginning of operation. Specifically, the initial power command setting unit 24 sets an individual power command for each storage battery 5 so as to reduce the frequency of use of the low-capacity battery compared to operational batteries that are storage batteries other than the low-capacity battery. For example, the initial power command setting unit 24 stops operation of a low-capacity battery (e.g., storage battery 5a) by setting the individual power command to zero, and for operational batteries other than the low-capacity battery (e.g., storage batteries 5b to 5d), sets the individual power command for each storage battery 5 by evenly distributing the system required power Pall obtained from the grid monitoring system 6. Note that the method of setting individual power commands for low-capacity batteries and operational batteries is not limited to the above.

[0025] That is, since the low-capacity battery only needs to be used less frequently than the operational battery, the system required power Pall may be equally allocated to the low-capacity battery in the same manner as the operational battery, for example, at a predetermined frequency (e.g., 20% of the operational battery's usage rate of 100%). Also, the allocation rate of the system required power to the low-capacity battery may be set lower than that of the operational battery. Furthermore, for the operational batteries, the system required power Pall may be allocated to each operational battery at a ratio according to the full charge capacity, for example. In addition, when the battery capacity of the battery system 1 is not sufficient for the power required from the power grid, it is difficult to reduce the frequency of use of the low-capacity battery, so in this case, it is necessary to set an individual power command for the low-capacity battery similar to that for other operating batteries. In this way, for the low-capacity battery, an appropriate individual power command can be set based on the relationship between the system required power from the power grid and the battery capacity of the battery system 1.

[0026] When the initial power command setting unit 24 sets the individual power commands for each storage battery 5, it transmits the individual power commands to the power conversion devices 7 corresponding to each storage battery 5. As a result, in each storage battery, charge and discharge control according to the individual power commands is performed.

[0027] In this way, by reducing the frequency of use of a low-capacity battery (e.g., storage battery 5a) compared to an operational battery (e.g., storage batteries 5b to 5d), it is possible to gradually bring the full charge capacity of the operational battery, which shows a high full charge capacity at the beginning of operation, closer to the full charge capacity of the low-capacity battery, as illustrated in FIG. 5, for example.

[0028] The setting cancellation unit 25 acquires a deterioration evaluation value of each of the storage batteries 5a-5d after the storage batteries 5a-5d have been set as a low-capacity battery (for example, the storage battery 5a). For example, the setting cancellation unit 25 acquires the deterioration evaluation value of each of the storage batteries 5a-5d stored in the memory unit 22 every time the deterioration evaluation value of each of the storage batteries 5a-5d is updated. Then, when the acquired deterioration evaluation value of each of the storage batteries 5a-5d satisfies a predetermined cancellation condition, the setting cancellation unit 25 cancels the setting of the low-capacity battery (for example, the storage battery 5a).

[0029] Examples of the release conditions include (i) when the differences between the deterioration evaluation values ​​of each operational battery (e.g., storage batteries 5b to 5d) and the deterioration evaluation value of the low-capacity battery are all below the release threshold, and (ii) when the difference between a representative value (e.g., minimum value, maximum value, average value, average value-N times standard deviation, etc.) of the deterioration evaluation values ​​of each operational battery and the deterioration evaluation value of the low-capacity battery is below the release threshold. In this manner, when the setting cancellation unit 25 cancels the low-capacity battery setting, the control switching unit 50 (see FIG. 3) switches to control by the mid-term operation control unit 30.

[0030] [Mid-term operation control unit 30] Fig. 6 is a functional configuration diagram showing an example of functions included in the medium-term operation control unit 30 according to this embodiment. As shown in Fig. 6, the medium-term operation control unit 30 includes, for example, a degradation state evaluation unit 31, a storage unit 32, a sharing adjustment rate setting unit 33, and a medium-term power command setting unit 34.

[0031] The degradation state evaluation unit 31 has the same function as the degradation state evaluation unit 21 included in the operation initial control unit 20, and acquires the degradation evaluation value of each of the storage batteries 5a to 5d. For example, the degradation state evaluation unit 31 performs degradation state evaluation to acquire the degradation evaluation value when a preset start condition is satisfied. Examples of the start condition include when a predetermined period has passed since the previous degradation state evaluation, when the cumulative operation time since the previous degradation state evaluation reaches a predetermined time, when a command to start the degradation state evaluation is input by a user, and the like. The start condition may be set as a combination of these. Also, the cycle of the degradation state evaluation may be set to be shorter as the degradation evaluation value decreases. The degradation evaluation value is as described above, and therefore a detailed description thereof will be omitted here.

[0032] The sharing adjustment rate setting unit 33 sets a sharing adjustment rate for each of the storage batteries 5a-5d based on a deterioration evaluation value (e.g., SOH) of each of the storage batteries 5a-5d stored in the memory unit 32. For example, the sharing adjustment rate setting unit 33 calculates a target deterioration evaluation value using the deterioration evaluation values ​​(e.g., SOH) of the storage batteries 5a-5d constituting the battery system 1, and sets a sharing adjustment rate for each storage battery 5 that brings the deterioration evaluation value of each of the storage batteries 5a-5d closer to the target deterioration evaluation value. The target deterioration evaluation value is, for example, an average value of the deterioration evaluation values ​​of the storage batteries 5a-5d.

[0033] As a result, a larger sharing adjustment rate is set for a storage battery with a high degradation evaluation value (e.g., a high SOH) than for a storage battery with a low degradation evaluation value. A storage battery 5 with a high sharing adjustment rate is assigned a larger portion of the required power relative to the system required power than a storage battery 5 with a low sharing adjustment rate. That is, when charging, a storage battery with a high sharing adjustment rate charges more power than a storage battery with a low sharing adjustment rate, and when discharging, a storage battery with a high sharing adjustment rate discharges more power than a storage battery with a low sharing adjustment rate.

[0034] For example, the sharing adjustment rate setting unit 33 calculates the sharing adjustment rate α(i) using a target deterioration evaluation value SOHave, which is the average value of the SOH of the storage batteries 5a to 5d, and each deviation ΔSOH(i) between the target deterioration evaluation value SOHave and the SOH(i) of each storage battery 5. As an example, the sharing adjustment rate α(i) is calculated by the following formula (1).

[0035] Sharing adjustment rate α(i)={1+K(ΔSOH(i) / SOHave)} (1)

[0036] In the above formula (1), i indicates identification information of the storage batteries 5a to 5d (for example, i=1 to 4), and for example, the sharing adjustment rate α(1) of the storage battery 5a is expressed by the following formula.

[0037] Sharing adjustment rate α(1)={1+K(ΔSOH(1) / SOHave)}

[0038] In the above formula (1), K is an adjustment gain, and the larger this adjustment gain K is, the shorter the time it takes for the variation in the degradation evaluation value to fall within a predetermined range. The adjustment gain K is a value equal to or greater than zero, and its upper limit is set within a range in which the sum of the individual power commands assigned to the operational batteries does not exceed the system required power. In the middle of the operation, the adjustment gain K is set to a value equal to or greater than 1, specifically, a value greater than 1.

[0039] The sharing adjustment rate setting unit 33 calculates the sharing adjustment rate α(i) using the latest deterioration evaluation value, for example, when the battery evaluation information stored in the memory unit 32 is updated, and updates each sharing adjustment rate α(i) in the memory unit 32.

[0040] After calculating the sharing adjustment rate α(i) for each of the storage batteries 5a to 5d, the sharing adjustment rate setting unit 33 stores sharing adjustment rate information that associates the identification information of each storage battery with the sharing adjustment rate α(i) in the storage unit 32. Time information and the like may be added to the sharing adjustment rate information.

[0041] The medium-term power command setting unit 34 calculates an individual power command Pdiv(i) for each operating battery, for example, by using the sharing adjustment rate α(i) corresponding to each of the storage batteries 5a to 5d and the system required power Pall acquired from the grid monitoring system 6. Here, the operating battery is an operable storage battery, in other words, a storage battery (for example, the storage batteries 5a to 5d) capable of performing charge / discharge control in response to the system required power Pall.

[0042] The medium-term power command setting unit 34 acquires the sharing adjustment rate α(i) of each operating battery stored in the memory unit 32, and calculates the individual power command Pdiv(i) of each operating battery by using the acquired sharing adjustment rate α(i) and the system required power Pall in the following equation (2).

[0043] Pdiv(i)=Pall×(1 / N)×α(i) (2)

[0044] In the above formula (2), N represents the number of operating batteries. As can be seen from formula (2), a larger individual power command is set for an operating battery with a high degradation evaluation value (high health) than for an operating battery with a low degradation evaluation value. After the medium-term power command setting unit 34 assigns an individual power command Pdiv(i) to each operating battery, it transmits the individual power command Pdiv(i) to the power conversion device 7 corresponding to each operating battery. As a result, charging and discharging control according to the individual power command Pdiv is performed in each operating battery.

[0045] For example, if the SOH(2) of the storage battery 5b is higher than the SOH(1) of the storage battery 5a, that is, SOH(1) < SOH(2), as shown in FIG. 7, when the sharing adjustment rate α(1) of the storage battery 5a is set to 0.8 and the sharing adjustment rate α(2) of the storage battery 5b is set to 1.2, an example of the individual power command, charge / discharge current, and SOC is compared and shown in FIGS. 8 to 10 respectively. In FIGS. 8 to 10, the solid line indicates the storage battery 5a, and the broken line indicates the storage battery 5b. As shown in FIGS. 8 to 10, since the individual power command of the storage battery 5b is larger than that of the storage battery 5a, the charge / discharge current of the storage battery 5b becomes larger than that of the storage battery 5a, and the amplitude of the SOC also becomes a larger value than that of the storage battery 5a.

[0046] Then, when the control of the storage battery 5 based on the sharing adjustment rate α according to the deterioration evaluation value is repeatedly performed by the operation middle - term control unit 30, and the state of the storage battery 5 satisfies the operation late - term condition, the control switching unit 50 (see FIG. 3) switches to the control by the operation late - term control unit 40. The operation late - term conditions are, for example, (i) when a parameter indicating the battery state of the operating storage battery (for example, voltage, SOC, temperature, etc.) becomes equal to or lower than a late - term determination reference value set based on the allowable lower limit value in operation, (ii) when the representative value (for example, average value, minimum value, or maximum value, etc.) of the SOH of the storage batteries of the battery system 1 becomes equal to or lower than a late - term threshold value, (iii) when the cumulative operation time of the battery system 1 becomes equal to or longer than a predetermined time, and the like.

[0047] 〔Operation late - term control unit 40〕 FIG. 11 is a functional configuration diagram showing an example of the functions provided in the operation late - term control unit 40 according to the present embodiment. As shown in FIG. 11, the operation late - term control unit 40 includes, for example, a deterioration state evaluation unit 41, a storage unit 42, a sharing adjustment rate setting unit 43, an individual offset power setting unit 44, and a late - term power command setting unit 45. Regarding the deterioration state evaluation unit 41 and the sharing adjustment rate setting unit 43, since they have the same functions as the deterioration state evaluation unit 31 and the sharing adjustment rate setting unit 33 provided in the operation middle - term control unit 30, detailed descriptions here are omitted, and the storage unit 42, the individual offset power setting unit 44, and the late - term power command setting unit 45 will be mainly described.

[0048] For example, when the mid-term operation control unit 30 described above performs control to change the power sharing in accordance with the deterioration evaluation value of the storage battery 5, the central value of the state of charge (SOC) may vary over time among the storage batteries, as shown in Fig. 12. Fig. 12 is a diagram comparing the time progression (solid line) of the SOC of a storage battery (e.g., storage battery 5a) having a relatively small sharing adjustment rate, in other words, a relatively low deterioration evaluation value (e.g., SOH), with the time progression (dotted line) of a storage battery (e.g., storage battery 5b) having a relatively large sharing adjustment rate, in other words, a relatively high deterioration evaluation value (e.g., SOH).

[0049] For example, the discharge current tends to be large and the charge current tends to be small for the storage battery 5b (e.g., a storage battery with a sharing adjustment rate of 1 or more), and the discharge current tends to be small and the charge current tends to be large for the storage battery 5a (e.g., a storage battery with a sharing adjustment rate of less than 1). Even if power sharing based on a deterioration evaluation value (e.g., SOH) is not performed as in the mid-term operation control unit 30, the degree of variation in the central value of the charging rate among such storage batteries varies to a certain extent due to individual differences between the storage batteries.

[0050] Furthermore, as illustrated in Figure 12, when there is variation in the median SOC value between storage batteries, the upper or lower limit value of the charging rate is more likely to reach the allowable upper or lower limit value of the battery system 1 than when there is no variation, which may shorten the life of the battery system 1. Therefore, the post-operation control unit 40 includes an individual offset power setting unit 44 as a function for reducing the variation in the central SOC value between the storage batteries over time.

[0051] The individual offset power setting unit 44 includes an individual average calculation unit 61 , a total average calculation unit 62 , and an offset calculation unit 63 . The individual average calculation unit 61 calculates an individual average charging rate for each storage battery, for example, by using charging rate data for each storage battery 5 for a predetermined period. For example, battery information (current data, voltage data, temperature data, anomaly detection data, etc.) for each storage battery 5a-5d is repeatedly transmitted from the battery system 1 to the post-operation control unit 40 at predetermined time intervals. The individual average calculation unit 61 calculates an individual average charging rate by performing a smoothing process on the charging rate data (SOC data) for each storage battery for the predetermined period. An example of the smoothing process is a moving average.

[0052] For example, the individual average calculation unit 61 performs a smoothing process such as a moving average, and further calculates the average value thereof to calculate an individual average charging rate for each storage battery 5. In this embodiment, the case where the individual average charging rate is calculated by the moving average process is described as an example, but the present invention is not limited to this example. For example, the individual average calculation unit 61 may specify the maximum charging rate and the minimum charging rate in a predetermined period for each storage battery, and calculate the average value of the specified maximum charging rate and minimum charging rate as the individual average charging rate. In addition, the present invention is not limited to the above method, and it is possible to use a statistical method for calculating an approximate central value of the charging rate in a predetermined period as appropriate.

[0053] The overall average calculation unit 62 uses the charging rate data of the multiple storage batteries 5a to 5d for a predetermined period to calculate an overall average charging rate that serves as a reference for the entire battery system 1. For example, the overall average calculation unit 62 may calculate an average value of the individual average charging rates of the storage batteries calculated by the individual average calculation unit 61 as the overall average charging rate. Alternatively, the maximum charging rate and the minimum charging rate for the entire battery system 1 for the predetermined period may be identified, and the average value of these values ​​may be calculated as the overall average charging rate. As for the overall average charging rate, the charging rate data of the individual storage batteries for the predetermined period may be statistically processed to calculate a median value of the charging rates, and a known technique may be appropriately adopted as a specific method.

[0054] The above-mentioned predetermined period can be set appropriately depending on the operation of the battery system 1. For example, a simulation can be performed in advance, and a period during which the central value of the charging rate varies across the entire battery system can be set as the predetermined period.

[0055] The offset calculation unit 63 calculates an individual offset power for each storage battery 5 to bring the individual average charging rate of each storage battery 5 closer to the overall average charging rate. For example, in the case of the storage battery 5a, the deviation between the individual average charging rate of the storage battery 5a and the overall average charging rate is calculated, and an individual offset power is calculated to make the deviation zero by performing proportional-integral control on the deviation. Similarly, an individual offset power is calculated for each of the storage batteries 5b to 5d. After calculating the individual offset power for each of the storage batteries 5a to 5d, the offset calculation unit 63 stores individual offset information that associates the identification information of each storage battery with the individual offset power in the storage unit 42. As a result, the individual offset information is stored in the storage unit 42, and the individual offset information is updated at predetermined intervals.

[0056] The later-stage power command setting unit 45 acquires the individual offset power Ps(i) and the sharing adjustment rate α(i) stored in the storage unit 42, and sets the individual power command Pdiv'(i) of the operating battery using the acquired individual offset power Ps(i) and sharing adjustment rate α(i) for each storage battery. For example, the individual power command Pdiv'(i) is given by the following formula (3).

[0057] Pdiv'(i)={Pall×(1 / N)×α(i)}+Ps(i) (3) Here, α(i)={1+K(ΔSOH(i) / SOHave)}

[0058] Here, in the later stages of operation, it is preferable to set the adjustment gain K to approximately 1. For example, when the adjustment gain K=1, the sharing adjustment rate α(i) of each of the storage batteries 5a to 5d is given by the following formula (1.1) from the above formula (1).

[0059] Sharing adjustment rate α(i)={1+(ΔSOH(i) / SOHave)} (1.1)

[0060] For example, if SOHave = 50% and SOH(1) for i = 1 is the same at 50%, then ΔSOH(1) = 0%, so the sharing adjustment rate α(1) is as follows.

[0061] Sharing adjustment rate α(1)={1+(ΔSOH(1) / SOHave)}=1

[0062] Also, if SOHave = 50% and SOH(2) for i = 2 = 100% (twice the SOH of the battery for i = 1), then ΔSOH(2) = 50%, so the sharing adjustment rate α(2) is as follows.

[0063] Sharing adjustment rate α(2)={1+(ΔSOH(2) / SOHave)}=2

[0064] In other words, for a battery with twice the SOH, the sharing adjustment rate is also doubled, and twice the charging and discharging is performed. This type of control makes it possible to operate each battery so that its SOC behavior is roughly the same.

[0065] When the adjustment gain K is set to zero in the later operation stage, the sharing adjustment rate of each of the storage batteries 5a to 5d is all 1, and in this case, there is no increase or decrease in the power sharing according to the SOH(i). That is, the system required power is allocated equally to each storage battery, and an individual power command Pdiv'(i) is given in which the individual offset power Ps(i) is added to the allocated portion. Note that when the adjustment gain K is set to zero in the later operation stage, there is no need to calculate the sharing adjustment rate, and therefore the sharing adjustment rate setting unit 43 can be omitted.

[0066] When the later-stage power command setting unit 45 sets the individual power command Pdiv'(i) for each operational battery, it transmits the individual power command Pdiv'(i) to the power conversion device 7 corresponding to each operational battery. As a result, in each operational battery, charge / discharge control according to the individual power command Pdiv'(i) is performed.

[0067] Next, the operation of the battery control system 10 according to this embodiment will be described. First, the initial operation control according to this embodiment will be described with reference to FIG. 13. FIG. 13 is a flowchart showing an example of a processing procedure of the initial operation control according to this embodiment. In the following description, a case where SOH is used as a deterioration evaluation value will be described as an example.

[0068] First, during the initial operation of the battery system 1, the battery control system 10 acquires the full charge capacity (Ah) of each of the storage batteries 5a-5d constituting the battery system 1, and calculates the SOH using the acquired full charge capacity (SA1). Next, the battery control system 10 calculates the difference between the maximum and minimum values ​​of the SOH (SA2), and determines whether the difference is greater than a set threshold (SA3). As a result, if the difference is equal to or less than the set threshold (SA3: NO), the system switches to mid-term operation control (SA9), and ends this process.

[0069] On the other hand, in step SA3, if the difference is greater than the set threshold (SA3: YES), the storage battery 5 with the minimum SOH is set as a low-capacity battery (SA4). Next, charge / discharge control of the storage battery 5 is performed based on the control algorithm at the beginning of operation (SA5). For example, the individual power command for the low-capacity battery is set to zero to stop operation, and the system required power Pall is evenly distributed for the operating batteries other than the low-capacity battery to set the individual power command for each storage battery. Then, the set individual power command is given to each power conversion device 7 of the battery system 1 to perform charge / discharge control of the storage battery 5 based on the individual power command.

[0070] Next, it is determined whether the SOH in the storage unit 22 (see FIG. 4) has been updated (SA6), and if it has not been updated (SA6: NO), the process returns to step SA5, and charging and discharging control of the storage battery 5 is performed based on the control algorithm at the beginning of operation. On the other hand, if it has been updated (SA6: YES), it is determined whether the cancellation condition is satisfied (SA7). As a result, if the cancellation condition is not satisfied (SA7: NO), the process returns to step SA5, and the above-mentioned process is repeated. On the other hand, if the cancellation condition is satisfied (SA7: YES), the low-capacity battery setting is cancelled (SA8), and the process is switched to mid-operation control (SA9), and this process is terminated.

[0071] Next, the mid-term operation control according to this embodiment will be described with reference to Fig. 14. Fig. 14 is a flowchart showing an example of a processing procedure of the mid-term operation control according to this embodiment. First, the sharing adjustment rate is calculated based on the latest SOH of each storage battery and stored in the storage unit 32 (see FIG. 6) (SB1). Next, the charge / discharge control of the storage battery 5 based on the control algorithm for the mid-operation period is performed (SB2). Specifically, the sharing adjustment rate α(i) of each storage battery 5a-5d is acquired from the storage unit 32, and an individual power command is set for each operating battery using the acquired sharing adjustment rate α(i), and each individual power command is transmitted to each operating battery. As a result, the charge / discharge control reflecting the deterioration evaluation value (for example, SOH(i)) of each operating battery is performed. Next, it is determined whether or not the SOH stored in the storage unit 32 has been updated (SB3). As a result, if the SOH has not been updated (SB3: NO), the process returns to step SB2, and the charge / discharge control of the storage battery 5 based on the control algorithm for the mid-operation period is performed. On the other hand, if the SOH has been updated (SB3: YES), it is determined whether or not the deterioration state of the storage battery 5 satisfies the late operation condition (SB4). Specifically, it is determined whether or not the representative value of the SOH of the storage battery 5 is equal to or less than the late operation threshold value. As a result, if the later stage operation conditions are not satisfied (SB4: NO), the process returns to step SB1, the sharing adjustment rate is calculated using the latest SOH, the sharing adjustment rate is stored in the memory unit 32, and subsequent processing is performed. On the other hand, if the later stage operation conditions are satisfied in step SB4 (SB4: YES), the process switches to later stage operation control (SB5), and ends this process.

[0072] Next, the later stage operation control according to this embodiment will be described with reference to Fig. 15. Fig. 15 is a flowchart showing an example of a processing procedure of the later stage operation control according to this embodiment. First, an individual offset power is calculated based on battery information acquired from each battery system 1 and stored in the memory unit (SC1). Next, charge / discharge control of the storage battery 5 is performed based on a control algorithm for the later stage of operation (SC2). Specifically, the sharing adjustment rate α(i) and individual offset power Ps(i) of each storage battery 5a-5d are acquired from the memory unit 42 (see FIG. 11), and individual power commands are set for each operational battery using the sharing adjustment rate α(i) and the individual offset power Ps(i), and each individual power command is transmitted to each operational battery.

[0073] Next, it is determined whether the SOH stored in the memory unit 42 has been updated (SC3). As a result, if the SOH has been updated (SA3: YES), the sharing adjustment rate is calculated using the new SOH and stored in the memory unit 42 (SC4), and the process proceeds to step SC5.

[0074] On the other hand, if the SOH has not been updated (SC3: NO), it is determined whether or not the update condition of the individual offset power is satisfied (SC5). As a result, if the update condition is satisfied (SC5: YES), for example, if a predetermined period has passed since the previous calculation of the individual offset power, the process returns to step SC1 and performs the subsequent process. On the other hand, if the update condition is not satisfied in step SC5 (SC5: NO), it is determined whether or not the battery system 1 has satisfied the operation stop condition (SC6). Specifically, it is determined whether or not the upper limit value of the charging rate of each of the storage batteries 5a to 5d has reached the allowable upper limit value, or whether or not the lower limit value of the charging rate of each of the storage batteries 5a to 5d has reached the allowable lower limit value. As a result, if the operation stop condition is not satisfied (SC6: NO), the process returns to step SC2 and performs charge / discharge control of the storage battery 5 based on the control algorithm in the later stage of operation. On the other hand, if the battery system 1 satisfies the operation stop condition (SC6: YES), it is considered that the life of the battery system 1 has arrived, and a notice of operation stop is issued (SC7), and the process ends.

[0075] As described above, the battery control system 10 according to this embodiment includes an initial operation control unit 20 that performs initial operation control during initial operation including the start of the battery system 1. Specifically, the initial operation control unit 20 includes a low-capacity battery setting unit 23 that sets a low-capacity battery to be used less frequently based on a deterioration evaluation value (e.g., full charge capacity) related to the full charge capacity of each of the storage batteries 5a to 5d, an initial power command setting unit 24 that sets an individual power command for the storage battery 5 so as to reduce the frequency of use of the low-capacity battery compared to the operating batteries that are storage batteries other than the low-capacity battery, and a setting cancellation unit 25 that acquires a deterioration evaluation value of each of the storage batteries 5a to 5d after the low-capacity battery has been set and cancels the low-capacity battery setting when the acquired deterioration evaluation value of each of the storage batteries 5a to 5d satisfies a predetermined condition.

[0076] In this way, when the battery system 1 is started, if there is variation in the degradation evaluation values, for example, the full charge capacity, the storage battery with the low full charge capacity is set as a low-capacity battery and is stopped or used less frequently to slow down the progression of battery degradation, while the operational batteries other than the low-capacity battery are actively used to speed up the progression of battery degradation. Then, when the full charge capacities of the low-capacity battery and the operational battery become close to each other and meet certain cancellation requirements, the low-capacity battery setting is cancelled and the battery can be operated in the same way as the other storage batteries. This makes it possible to quickly reduce the variation in full charge capacity at the time of system start-up.

[0077] The battery control system 10 according to the present embodiment also includes a medium-term operation control unit 30 that controls charging and discharging of the storage batteries 5a-5d in the medium-term operation after the low-capacity battery setting is released. The medium-term operation control unit 30 includes, for example, a sharing adjustment rate setting unit 33 that calculates a sharing adjustment rate based on a deterioration evaluation value (e.g., SOH) of each storage battery, and a medium-term power command setting unit 34 that sets individual power commands for each storage battery 5a-5d using the sharing adjustment rate. This makes it possible to suppress variations in deterioration evaluation values ​​(e.g., SOH) between the storage batteries in the medium-term operation of the battery system 1, and to extend the life of the battery system as a whole.

[0078] Furthermore, the battery control system 10 according to this embodiment includes a later-stage operation control unit 40 that controls charging and discharging of the storage batteries 5a to 5d in a later-stage operation after the battery system 1 satisfies preset later-stage operation conditions. The later-stage operation control unit 40 includes an individual offset power setting unit 44 that calculates an individual offset power Ps(i) for each storage battery 5 using charging rate data of each storage battery 5, and a later-stage power command setting unit 45 that sets an individual power command for each storage battery 5 using the individual offset power Ps(i) for each storage battery 5.

[0079] In this way, since the individual power command for each operational battery is set using the individual offset power Ps, it is possible to suppress the variation in the median SOC value between the storage batteries over time, for example, as shown in Fig. 16. This makes it possible to lengthen the time until the maximum and minimum charging rates of each operational battery reach the allowable upper and lower limits, and to extend the life of the entire battery system.

[0080] In this embodiment, in the later stage of operation, the individual power command is set using the individual offset power Ps(i), but this is not limited to this. For example, the individual power command for each storage battery 5 may be set without using the individual offset power Ps(i). That is, the individual power command in this case is given by the following formula.

[0081] Pdiv'(i) = {Pall × (1 / N) × α(i)} Here, α(i) = 1 + (ΔSOH(i) / SOHave)

[0082] Second Embodiment Next, a power supply and demand system, a battery control system, a battery control method, and a battery control program according to a second embodiment of the present disclosure will be described with reference to the drawings. In the above-described first embodiment, the post-operation control unit 40 includes an individual offset power setting unit 44, which performs control to reduce the variation in the central value of the state of charge (SOC) between the storage batteries. In contrast, in this embodiment, the state of charge of the entire battery system 1 is adjusted to extend the life of the entire battery system 1.

[0083] For example, each storage battery 5 constituting the battery system 1 includes a power conversion device 7, a cell monitoring unit (CMU) that monitors the deterioration state of the battery cells, and the like, and these devices cause power loss. Since the amount of this power loss changes over time, the central value of the charge / discharge range of the battery system 1 as a whole gradually changes. For example, as shown in FIG. 17, in the early stages of operation, charging and discharging are performed around a state of charge (SOC) of 50%, whereas in the later stages of operation, charging and discharging may be performed around an SOC of 50% or less. In this way, when the central value of the charge / discharge range of the battery system 1 as a whole decreases, the minimum SOC (SOCmin in FIG. 17) is more likely to reach the lower allowable limit of the storage battery, and the battery life may be shortened.

[0084] Therefore, the post-operation control unit 40a of the battery control system according to this embodiment has a function for suppressing such a change in the central value of the SOC of the entire battery system over time. In the following, the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted, and the different components are mainly described.

[0085] Fig. 18 is a functional configuration diagram showing an example of functions provided in the later operation control unit 40a of the battery control system according to this embodiment. As shown in Fig. 18, the later operation control unit 40a of this embodiment includes an overall offset power setting unit 46, a system required power correction unit 47, and a later power command setting unit 45a.

[0086] The overall offset power setting unit 46 includes an overall average calculation unit 71 and an offset calculation unit 72. The overall average calculation unit 71 calculates the overall average charging rate of the battery system 1, for example, by using charging rate data of the battery system 1 during a predetermined period. For example, the overall average calculation unit 71 can calculate the overall average charging rate by a method similar to that of the overall average calculation unit 62 of the first embodiment described above. For example, the overall average calculation unit 71 may calculate the average of the moving average values ​​calculated for each storage battery as the overall average charging rate. In addition, the maximum charging rate and the minimum charging rate during a predetermined period may be specified for the entire battery system 1, and the average value of these values ​​may be calculated as the overall average charging rate. The overall average charging rate may be calculated by statistically processing the charging rate data of each storage battery during a predetermined period and calculating the center value of the charging rate, and a specific method for this may be appropriately adopted from a known technology.

[0087] Note that the specific period and the like can be set appropriately depending on the operation of the battery system 1. For example, a simulation can be performed in advance, and the predetermined period can be set as a period during which the difference between the central value of the charging rate and the central value at the beginning of operation becomes equal to or greater than a predetermined value for the entire battery system.

[0088] The offset calculation unit 72 calculates an overall offset power for bringing the overall average charging rate of the battery system 1 closer to a target charging rate (e.g., 50%). For example, the offset calculation unit 72 calculates a deviation between the overall average charging rate and the target charging rate, and calculates an overall offset power Pg that makes the deviation zero by performing proportional-integral control on the deviation. After calculating the overall offset power Pg, the offset calculation unit 72 stores the overall offset power Pg in the storage unit 42. Furthermore, the offset calculation unit 72 updates the overall offset power Pg in the storage unit 42 every time it calculates the overall offset power Pg.

[0089] The system required power correction unit 47 corrects the system required power received from the grid monitoring system 6 by using the latest total offset power Pg. For example, the system required power correction unit 47 reads out the latest total offset power Pg stored in the storage unit 42, and adds the total offset power Pg to the system required power Pall to calculate the corrected system required power Pall' (=Pall+Pg). This process is performed, for example, every time the system required power is received from the grid monitoring system 6.

[0090] The system required power correction unit 47 outputs the corrected system required power Pall' to the later power command setting unit 45a. The later power command setting unit 45a acquires the sharing adjustment rate α(i) stored in the memory unit 42, and sets an individual power command Pdiv'(i) for the operating battery using the acquired sharing adjustment rate α(i) for each storage battery and the corrected system required power Pall'. For example, the individual power command Pdiv'(i) is given by the following equation (4).

[0091] Pdiv'(i)={Pall'×(1 / N)×α(i)} (4)

[0092] As a result, each operating battery is given an individual power command that is based on a deterioration evaluation value (e.g., SOH) and suppresses changes in the central value of the SOC of the entire battery system over time, and charging and discharging control of the power conversion device 7 is performed based on this individual power command.

[0093] As described above, the operation later control unit 40a of the battery control system according to this embodiment includes an overall offset power setting unit 46 that calculates an overall offset power Pg for correcting the system required power, and a system required power correction unit 47 that corrects the system required power Pall using the overall offset power Pg. Then, the later power command setting unit 45a sets individual power commands for each operational battery using the sharing adjustment rate α(i) and the corrected system required power Pall'.

[0094] This makes it possible to suppress the change in the median value of the SOC of the entire battery system over time, which in turn makes it possible to lengthen the time it takes for the maximum and minimum charging rates of the storage battery to reach the allowable upper and lower limits, thereby extending the life of the entire battery system.

[0095] [Variation 1] In this embodiment, the total offset power is calculated using the total average charging rate of the battery system 1, but this is not limited to this. Fig. 19 shows a functional configuration diagram of a post-operation control unit 40b according to Modification 1. As shown in Fig. 19, the total offset power setting unit 46a includes a representative charging rate determination unit 73 and an offset calculation unit 74.

[0096] The representative charging rate determination unit 73 determines an upper limit representative charging rate and a lower limit representative charging rate of the battery system 1 using charging rate data of the battery system 1 for a predetermined period. An example of the upper limit representative charging rate is the maximum charging rate of the battery system 1, and an example of the lower limit representative charging rate is the minimum charging rate of the battery system 1. The upper limit representative charging rate and the lower limit representative charging rate are not limited to these. For example, the average of the maximum charging rates of the batteries 5a-5d may be set as the upper limit representative charging rate, and the average of the minimum charging rates of the batteries 5a-5d may be set as the lower limit representative charging rate. Furthermore, the upper limit representative charging rate and the lower limit representative charging rate may be determined using statistical processing such as moving average.

[0097] The offset calculation unit 74 calculates the difference between the upper limit representative charging rate and the allowable upper limit of the charging rate (upper limit difference) and the difference between the lower limit representative charging rate and the allowable lower limit of the charging rate (lower limit difference), and calculates the total offset power for bringing the deviation between the upper limit difference and the lower limit difference closer to zero. For example, the total offset power is calculated by performing proportional-integral control on the deviation.

[0098] According to the entire offset power setting unit 46a of the first modification, it is possible to control the operational fluctuation range of the charging rate of the entire battery system to be about the center between the allowable upper limit value and the allowable lower limit value. This makes it possible to suppress a gradual shift in the center of the operational fluctuation range of the charging rate of the entire battery system, thereby making it possible to extend the life of the battery system.

[0099] The post-operation control unit may include the above-mentioned overall offset power setting unit and individual offset power setting unit. In this way, by using the individual offset power and the overall offset power, it is possible to suppress the deviation over time of the central value of the SOC of the entire battery system and the deviation of the central value of the SOC between the storage batteries constituting the battery system 1. This can be expected to further extend the life of the battery system 1.

[0100] Third Embodiment Next, a power supply and demand system, a battery control system, a battery control method, and a battery control program according to a third embodiment of the present disclosure will be described with reference to the drawings. In the power supply and demand system 100 according to the first embodiment described above, the power conversion device 7 is an AC / DC converter, and a case has been described in which the battery system 1 is connected to the AC link 4 via the power conversion device 7. In contrast, in a power supply and demand system 100a according to this embodiment, as shown in FIG. 20, the battery system 1a is connected to a DC link 8 via a power conversion device 7' (7a' to 7d') which is a DC / DC converter. In addition, the DC link 8 and the substation 3 are connected via an AC / DC converter 9.

[0101] Hereinafter, configurations common to the battery control system according to the first embodiment will be denoted by the same reference numerals, and description thereof will be omitted, and different configurations will be mainly described. Fig. 21 is a functional configuration diagram showing an example of functions of the medium-term operation control unit 30a of the battery control system according to this embodiment. As shown in Fig. 21, in this embodiment, the functions of the sharing adjustment rate setting unit 33a and the medium-term power command setting unit 34a are different from those in the first embodiment described above.

[0102] When the battery system 1a is connected to the DC link 8, it is necessary to control the charging and discharging of the battery system 1 so that the bus voltage of the DC link 8 falls within a voltage range required by the power grid. For example, when the voltage of the DC link 8 rises due to the supply of power from the power grid 2, the battery system 1a is charged with power corresponding to the voltage rise, thereby suppressing the voltage rise of the DC link 8. Conversely, when the voltage of the DC link 8 drops due to the supply of power to the power grid 2, the battery system 1a is discharged with power corresponding to the voltage drop, thereby suppressing the voltage drop of the DC link 8.

[0103] Fig. 22 is a diagram showing the relationship between the individual power commands according to this embodiment and the bus voltage of the DC link 8. In Fig. 22, the horizontal axis represents power, and the vertical axis represents the differential voltage between the target voltage of the DC link 8 and the operating voltage of the DC link 8, and the relationship between the differential voltage and the individual power commands is indicated by a solid line. In FIG. 22, +Vm_max is, for example, the maximum allowable voltage for the target voltage of the DC link 8, and -Vm_max is, for example, the minimum allowable voltage for the target voltage of the DC link 8. In other words, Vm_max and -Vm_max respectively indicate the upper limit and lower limit of the allowable voltage range for the target voltage of the DC link 8. Here, the maximum allowable voltage and the minimum allowable voltage are merely examples and are not limited thereto. That is, they may be set appropriately depending on the operation of the battery system 1 and the like. Also, in FIG. 22, -Pmax indicates the upper limit charge power of the power conversion device 7' and +Pmax indicates the upper limit discharge power of the power conversion device 7' as examples, but are not limited thereto. That is, they may be set appropriately depending on the operation of the battery system 1 and the like. From FIG. 22, the relationship between the individual power command Pdiv and the differential voltage Vp is expressed by the following equation (5).

[0104] Vp = -a × Pdiv (5) where a=Vmax / Pmax

[0105] When the above equation (5) is converted into a derivation equation for Pdiv, the following equation (6) is obtained. Pdiv=-Vp / a (6)

[0106] As shown in Fig. 22, when the current differential voltage Vp = +ΔV1, the individual power command Pdiv is P1 (charging), and when the current differential voltage Vp = -ΔV2, the individual power command Pdiv is P2 (discharging). From Fig. 22, it can be seen that the individual power command Pdiv is set to a larger value as the operating voltage of the DC link 8 deviates from the target voltage. It can also be seen that when the slope a is increased, the individual power command decreases, and when the slope a is decreased, the individual power command increases. Therefore, in this embodiment, the slope a is changed according to the deterioration evaluation value, more specifically, the sharing adjustment rate α(i) calculated in the first embodiment, thereby performing charge / discharge control of each storage value according to the deterioration evaluation value.

[0107] In this embodiment, the sharing adjustment rate setting unit 33a calculates the slope a(i) by using the sharing adjustment rate α(i) of each storage battery in the following equation (7).

[0108] a(i)=a×{1 / α(i)} (7)

[0109] In equation (7), a(i) is the slope of the storage battery with identification information i, a is the default slope (a=Vmax / Pmax), and α(i) is the sharing adjustment rate of the storage battery with identification information i, and is calculated using equation (1) described in the first embodiment. As can be seen from equation (7), a smaller slope is set for an operating battery with a high degradation evaluation value (high health) than for an operating battery with a low degradation evaluation value.

[0110] After calculating the slope a(i) for each storage battery, the sharing adjustment rate setting unit 33a stores slope information that associates the identification information of each storage battery with the slope in the storage unit 32. Time information and the like may be added to the slope information.

[0111] The medium-term power command setting unit 34a calculates an individual power command Pdiv(i) for each operating battery using the gradient a(i) corresponding to each storage battery and the operating voltage (actually measured voltage) of the DC link 8. For the operating voltage of the DC link 8, for example, information notified from the battery system 1, more specifically, from the power conversion device 7′, can be used. Specifically, the medium-term power command setting unit 34a acquires the slope a(i) of each storage battery stored in the memory unit 32, and calculates the individual power command Pdiv(i) of each storage battery by using the acquired slope a(i) and the differential voltage Vp between the operating voltage of the DC link 8 and the target voltage in the following equation (8).

[0112] Pdiv(i)=-Vp / a(i) (8)

[0113] When the medium-term power command setting unit 34a sets the individual power command Pdiv(i) for each operational battery, it transmits the individual power command Pdiv(i) to the power conversion device 7' corresponding to each operational battery. As a result, in each operational battery, charge / discharge control according to the individual power command Pdiv(i) is performed.

[0114] For example, an example of the slope and individual power commands when the SOH(2) of battery 5b is higher than the SOH(1) of battery 5a is shown in comparison in Fig. 23. As shown in Fig. 23, the individual power commands Pc(2), Pd(2) of battery 5b are larger than those of battery 5a, so the charge / discharge current of battery 5b is larger than that of battery 5a, and the amplitude of the SOC is also larger than that of battery 5a.

[0115] In this way, when the battery system 1a is connected to the DC link 8, it is possible to set an individual power command for each storage battery based on the SOH using the slope information.

[0116] 24 is a functional configuration diagram showing an example of functions of the later operation control unit 40c according to this embodiment. As shown in FIG. 24, the later operation control unit 40c is different from the first embodiment in that it includes a sharing adjustment rate setting unit 43a and a later power command setting unit 45c. Here, similar to the sharing adjustment rate setting unit 33a described above, when the sharing adjustment rate setting unit 43a calculates the slope a(i) for each storage battery, the sharing adjustment rate setting unit 43a stores slope information that associates the identification information of each storage battery with the slope in the storage unit 42. Here, time information or the like may be added to the slope information.

[0117] The later-stage power command setting unit 45c sets the individual power command Pdiv'(i) using the individual offset power Ps(i) calculated by the individual offset power setting unit 44. At this time, the individual power command Pdiv'(i) is given by the following equation (9).

[0118] Pdiv'(i) = Pdiv(i) + Ps(i) =-Vp / a(i)+Ps(i) (9)

[0119] Moreover, correcting the individual power command Pdiv(i) with the individual offset power Ps(i) corresponds to translating the power command characteristic along the X-axis as shown in Fig. 25. For this reason, for example, instead of the individual offset power Ps(i), the individual offset power setting unit 44 may store information on the intercept b(i) of the power command characteristic corresponding to the individual offset power Ps(i) in the storage unit 42. This makes it possible to calculate the individual power command Pdiv'(i) based on the information on the slope a(i) and the intercept b(i) when the battery system 1 is connected to the DC link 8.

[0120] It is also possible to apply the total offset power setting units 46, 46a of the second embodiment described above to the post-operation control unit 40c of this embodiment. In this case, the system required power correction unit 47 is omitted, and the total offset power calculated by the total offset power setting units 46, 46a is provided to the AC / DC converter 9 (see FIG. 20), and the AC / DC converter 9 performs power control based on the total offset power.

[0121] Although the present disclosure has been described above using the embodiments, the technical scope of the present disclosure is not limited to the scope described in the above embodiments. Various modifications or improvements can be made to the above embodiments without departing from the gist of the disclosure, and the forms in which such modifications or improvements are made are also included in the technical scope of the present disclosure. In addition, the above embodiments may be appropriately combined. Furthermore, the processing flow described in the above embodiment is also one example, and unnecessary steps may be deleted, new steps may be added, or the processing order may be rearranged, without departing from the spirit of the present disclosure.

[0122] For example, in each of the above-mentioned embodiments and modified examples, the battery control system 10 is described as including the storage units 22, 32, 42, but there are no particular limitations on the locations where the storage units 22, 32, 42 are installed. For example, the storage units 22, 32, 42 may be configured to be accessible by the battery control system 10, and as one example, may be configured to enable reading and writing of data from and to the storage units via a network.

[0123] In addition, in each of the above-mentioned embodiments and modifications, the battery control system 10 is provided with the degradation state evaluation units 21, 31, 41 that evaluate the degradation state of the battery system 1, 1a, but the present invention is not limited to this. For example, if the battery system 1 has the functions of the degradation state evaluation units 21, 31, 41, the degradation evaluation values ​​evaluated by the degradation state evaluation units 21, 31, 41 may be acquired. In addition, if the degradation evaluation values ​​evaluated by the degradation state evaluation units 21, 31, 41 are stored in a storage unit connected via a network, the degradation evaluation values ​​may be acquired from the storage unit at any time. The above-mentioned method for evaluating the degraded state of the storage battery 5 is also one example, and any known technique for evaluating the degraded state (degraded state) of a storage battery can be appropriately adopted.

[0124] The power supply and demand system, the battery control system, the battery control method, and the program described in the above-described embodiments can be understood, for example, as follows.

[0125] A battery control system (10) according to a first aspect of the present disclosure is a battery control system applied to a battery system (1) having a plurality of storage batteries (5), and includes a low-capacity battery setting unit (23) that sets a low-capacity battery to be used less frequently based on a deterioration evaluation value related to the full charge capacity of each of the storage batteries at the start of the battery system, an initial power command setting unit (24) that sets individual power commands for the storage batteries so as to reduce the frequency of use of the low-capacity battery compared to operational batteries which are storage batteries other than the low-capacity battery, and a setting cancellation unit (25) that acquires a deterioration evaluation value of each of the storage batteries after the low-capacity battery has been set, and cancels the setting of the low-capacity battery when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined cancellation condition.

[0126] According to the above aspect, when the battery system is started, a storage battery with a low deterioration evaluation value (e.g., full charge capacity) is set as a low-capacity battery, and the frequency of use of this low-capacity battery is reduced to slow the progression of battery deterioration, while the operational batteries other than the low-capacity battery are actively used to speed up the progression of battery deterioration. Then, when the full charge capacities of the low-capacity battery and the operational battery approach each other and satisfy a predetermined release requirement, the low-capacity battery is released from the setting, and the battery can be operated in the same way as the other storage batteries. This makes it possible to quickly reduce the variation in full charge capacity when the system is started.

[0127] In the battery control system (10) according to the second aspect of the present disclosure, in the first aspect described above, the setting cancellation unit (25) cancels the setting of the low-capacity battery when the difference between the deterioration evaluation value of each operational battery and the deterioration evaluation value of the low-capacity battery falls within a predetermined range.

[0128] According to the above aspect, when the deterioration evaluation value of the low-capacity battery and the deterioration evaluation value of the operational battery approach each other and the difference between them falls within a specified range, the low-capacity battery setting can be cancelled and the battery can be operated in the same way as other storage batteries.

[0129] A battery control system according to a third aspect of the present disclosure, in the first or second aspect described above, includes a sharing adjustment rate setting unit (33, 33a) that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries, and a medium-term power command setting unit (34, 34a) that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the settings of all of the low-capacity batteries have been released by the setting release unit (25).

[0130] According to the above aspect, in the intermediate operation period after all the low-capacity batteries have been released, individual power commands for each battery are set based on the sharing adjustment rate set using the deterioration evaluation value of each battery. This makes it possible to suppress the variation in the deterioration evaluation value between the batteries and extend the life of the battery system as a whole.

[0131] In the battery control system according to a fourth aspect of the present disclosure, in the above-mentioned third aspect, the sharing adjustment rate setting unit (33, 33a) calculates a target deterioration evaluation value using a deterioration evaluation value of each of the storage batteries (5), and sets a sharing adjustment rate for each of the storage batteries (5) such that the deterioration evaluation value of each of the storage batteries (5) approaches the target deterioration evaluation value.

[0132] According to the above aspect, it is possible to gradually bring the degradation evaluation value of each storage battery constituting the battery system closer to the target degradation evaluation value, thereby reducing the variation in the degradation evaluation value of each storage battery.

[0133] The battery control system according to a fifth aspect of the present disclosure, in the above-mentioned fourth aspect, includes a sharing adjustment rate setting unit (33, 33a) that calculates a target deterioration evaluation value using the deterioration evaluation value of each of the storage batteries, and sets a sharing adjustment rate for each of the storage batteries by multiplying an adjustment value that brings the deterioration evaluation value of each of the storage batteries closer to the target deterioration evaluation value by an adjustment gain that is set to a value greater than 1, and a medium-term power command setting unit (34, 34a) that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the settings of all of the low-capacity batteries are released by the setting release unit (25).

[0134] According to the above aspect, the allocation adjustment rate for each storage battery is set by multiplying an adjustment value that brings the deterioration evaluation value of each storage battery closer to the target deterioration evaluation value by an adjustment gain that is set to a value greater than 1, so that the deterioration evaluation value of each storage battery can be quickly brought closer to the target deterioration evaluation value.

[0135] A battery control system according to a sixth aspect of the present disclosure, in any of the first to fifth aspects above, includes a sharing adjustment rate setting unit (43, 43a) that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries (5), and a later stage power command setting unit (45, 45a, 45b) that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the battery system satisfies a preset later stage operation condition.

[0136] According to the above aspect, in the later stage of operation, an individual power command for each storage battery is set based on a sharing adjustment rate set using the deterioration evaluation value of each storage battery. This makes it possible to suppress the variation in the deterioration evaluation value between the storage batteries and to extend the life of the battery system as a whole.

[0137] A battery control system according to a seventh aspect of the present disclosure, in the first or second aspect described above, further includes a sharing adjustment rate setting unit (33, 33a) that calculates a target deterioration evaluation value using a deterioration evaluation value of each of the storage batteries (5) and sets a sharing adjustment rate for each of the storage batteries by multiplying an adjustment value that brings the deterioration evaluation value of each of the storage batteries closer to the target deterioration evaluation value by an adjustment gain, and a medium-term power command setting unit (33, 33a) that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the setting cancellation unit (25) cancels settings for all of the low-capacity batteries. and a later-stage power command setting unit (45, 45a, 45b) that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the battery system satisfies a preset later-stage operation condition, wherein the sharing adjustment rate setting unit (33, 33a, 43, 43a) sets the sharing adjustment rate used in the mid-term power command setting unit by using an adjustment gain greater than 1, and sets the sharing adjustment rate used in the later-stage power command setting unit by using an adjustment gain set to 1.

[0138] According to the above aspect, in the middle operation stage, the sharing adjustment rate for each storage battery is set by multiplying an adjustment value for bringing the degradation evaluation value of each storage battery closer to the target degradation evaluation value by an adjustment gain set to a value greater than 1, so that it is possible to quickly bring the degradation evaluation value of each storage battery closer to the target degradation evaluation value. Also, in the later operation stage, the sharing adjustment rate for each storage battery is set by multiplying an adjustment value for bringing the degradation evaluation value of each storage battery closer to the target degradation evaluation value by an adjustment gain set to 1, so that it is possible to perform control that restricts the operating range of the state of charge (SOC) and voltage of the storage battery compared to the middle operation stage.

[0139] A battery control system according to an eighth aspect of the present disclosure, in any of the first to seventh aspects above, includes an individual offset power setting unit (44) that calculates an individual offset power for each of the storage batteries using charging rate data of each of the storage batteries, and a later-stage power command setting unit (45) that sets an individual power command for each of the storage batteries using the individual offset power for each of the storage batteries after the battery system (1) satisfies a preset later-stage operation condition, and the individual offset power setting unit (44) includes an individual average calculation unit (61) that calculates an individual average charging rate for each of the storage batteries using charging rate data for each of the storage batteries in a predetermined period, an overall average calculation unit (62) that calculates an overall average charging rate that serves as a reference for the entire battery system, and an offset calculation unit (63) that calculates an individual offset power for each of the storage batteries to bring the individual average charging rate closer to the overall average charging rate.

[0140] According to the above aspect, in the later stage of operation after the battery system satisfies the preset later stage of operation condition, control is performed to bring the average value of the charging rate of each storage battery closer to the overall average charging rate. This makes it possible to suppress the variation in the median value of the SOC among the storage batteries over time. As a result, it is possible to lengthen the time until the maximum and minimum values ​​of the charging rate of each operating battery reach the allowable upper and lower limits, and it is possible to further extend the life of the entire battery system.

[0141] A battery control system according to a ninth aspect of the present disclosure, in any of the first to seventh aspects above, includes a sharing adjustment rate setting unit (43) that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries (5), an individual offset power setting unit (44) that calculates an individual offset power for each of the storage batteries using charging rate data of each of the storage batteries, and a later stage power command setting unit (45) that sets an individual power command for each of the storage batteries using the individual offset power for each of the storage batteries and the sharing adjustment rate after the battery system (1) satisfies a preset later stage operation condition, and the individual offset power setting unit (44) includes an individual average calculation unit (61) that calculates an individual average charging rate for each of the storage batteries using charging rate data for each of the storage batteries in a predetermined period, an overall average calculation unit (62) that calculates an overall average charging rate that is a reference for the entire battery system, and an offset calculation unit (63) that calculates an individual offset power for each of the storage batteries to bring the individual average charging rate closer to the overall average charging rate.

[0142] According to the above aspect, in the later stage of operation after the battery system satisfies the preset later stage of operation condition, the sharing adjustment rate set using the deterioration evaluation value of each storage battery and the individual offset power set using the charging rate data are used to set the individual power command for each storage battery. This makes it possible to suppress the variation in the deterioration evaluation value between the storage batteries and to suppress the variation in the central SOC value between the storage batteries over time. As a result, it becomes possible to effectively extend the life of the entire battery system.

[0143] A battery control system according to a tenth aspect of the present disclosure, in any of the first to ninth aspects above, includes an overall offset power setting unit (46) that calculates an overall offset power for correcting the system required power, a system required power correction unit (47) that corrects the system required power of the battery system using the overall offset power, and a later stage power command setting unit (45a) that sets individual power commands for each of the storage batteries using the corrected system required power after the battery system satisfies a preset later stage operation condition, wherein the overall offset power setting unit (46) includes an overall average calculation unit (71) that calculates an overall average charging rate, which is an average charging rate of the battery system, using charging rate data of the battery system for a predetermined period, and an offset calculation unit (72) that calculates an overall offset power for approximating the overall average charging rate to a predetermined reference charging rate.

[0144] According to the above aspect, in the later stage of operation after the battery system has satisfied the preset later stage of operation conditions, an overall average charging rate, which is the average charging rate of the battery system over a specified period of time, is calculated, an overall offset power is calculated to bring the calculated overall average charging rate closer to a specified reference charging rate, the system required power is corrected using the calculated overall offset power, and individual power commands for each operating battery are set based on the corrected system required power. This makes it possible to suppress the change in the central value of the charging rate of the entire battery system over time, which in turn makes it possible to lengthen the time until the maximum and minimum charging rates of the storage batteries reach the allowable upper and lower limits, thereby effectively extending the life of the entire battery system.

[0145] A battery control system according to an eleventh aspect of the present disclosure, in any one of the first to ninth aspects above, includes an overall offset power setting unit (46a) that calculates an overall offset power for correcting a system required power, a system required power correction unit (47) that corrects the system required power of the battery system (1) using the overall offset power, and a later-stage power command setting unit (45b) that sets individual power commands for each of the storage batteries using the corrected system required power after the battery system satisfies a preset later-stage operation condition, wherein the overall offset power setting unit (46a) includes a representative charging rate determination unit (73) that determines an upper limit representative charging rate and a lower limit representative charging rate of the battery system using charging rate data of the battery system for a predetermined period, and an offset calculation unit (74) that calculates an overall offset power for bringing a difference between the upper limit representative charging rate and a tolerance upper limit value of the charging rate and the difference between the lower limit representative charging rate and a tolerance lower limit value of the charging rate closer to zero.

[0146] According to the above aspect, in the later stage of operation after the battery system satisfies a preset later stage of operation condition, an upper representative charging rate that is a representative value of an upper limit side charging rate in the battery system and a lower representative charging rate that is a representative value of a lower limit side charging rate in the battery system are determined, and an overall offset power is calculated to bring the difference between the upper representative charging rate and the allowable upper limit of the charging rate and the difference between the lower representative charging rate and the allowable lower limit of the charging rate closer to zero. Then, the calculated overall offset power is used to correct the system required power, and control is performed to set individual power commands for each operating battery based on the corrected system required power. This makes it possible to suppress the change in the central value of the charging rate of the entire battery system over time. As a result, it is possible to lengthen the time until the maximum and minimum charging rates of the storage batteries reach the allowable upper and lower limits, and it is possible to effectively extend the life of the entire battery system. Furthermore, by using the maximum and minimum charging rates, it is possible to evenly arrange the charging and discharging range of the entire battery system between the allowable upper and lower limits, for example, even in cases where the charging and discharging control of the charging rates of some storage batteries is performed near the allowable upper and lower limits.

[0147] A power supply and demand system (100, 100a) according to a twelfth aspect of the present disclosure includes a battery system (1, 1a) including a plurality of storage batteries (5), and the battery control system (10, 10a) according to any one of the first to eleventh aspects.

[0148] A battery control method according to a thirteenth aspect of the present disclosure is a battery control method applied to a battery system (1) having a plurality of storage batteries (5), in which, at the start of the battery system, a computer executes the following steps: a step (SA4) of setting a low-capacity battery to reduce the frequency of use based on a deterioration evaluation value related to the full charge capacity of each of the storage batteries; a step (SA5) of setting individual power commands for the storage batteries so as to reduce the frequency of use of the low-capacity battery compared to operational batteries which are storage batteries other than the low-capacity battery; and a step (SA8) of acquiring a deterioration evaluation value of each of the storage batteries after the low-capacity battery has been set, and canceling the setting of the low-capacity battery when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined cancellation condition.

[0149] A battery control program according to a fourteenth aspect of the present disclosure is a program for causing a computer to function as the battery control system (10, 10a) according to any one of the first to eleventh aspects. [Explanation of symbols]

[0150] 1,1a: Battery system 2: Power system 3: Substation 4:AC Link 5(5a~5d):Storage battery 6: Grid monitoring system 7 (7a to 7d): Power conversion device 7'(7a'~7d'): Power conversion device 8: DC link 9: AC / DC converter 10: Battery control system 11: CPU 12: Main memory 13:Secondary storage device 14: Communication interface 15: Input device 16: Display 20: Initial operation control section 21: Deterioration state evaluation section 22,32,42: Storage part 23: Low capacity battery setting section 24: Initial power command setting section 25: Cancellation section 30, 30a: Mid-term operation control unit 31: Deterioration state evaluation section 33,33a: Sharing adjustment rate setting part 34,34a: Medium-term power command setting section 40, 40a, 40b, 40c: Post-operation control section 41: Deterioration state evaluation section 43,43a: Sharing adjustment rate setting section 44: Individual offset power setting section 45,45a,45b: Late power command setting section 46, 46a: Overall offset power setting section 47: System required power correction section 50: Control switching unit 61:Individual average calculation section 62: Overall average calculation section 63: Offset calculation section 71: Overall average calculation section 72: Offset calculation section 73:Representative charging rate determination section 74: Offset calculation section

Claims

1. A battery control system applied to a battery system including a plurality of storage batteries, a low-capacity battery setting unit that sets a low-capacity battery to be used less frequently based on a deterioration evaluation value related to a full charge capacity of each of the storage batteries at the start of the battery system; an initial power command setting unit that sets an individual power command for the storage battery so as to reduce the frequency of use of the low-capacity battery compared to an operational battery that is a storage battery other than the low-capacity battery; a setting release unit that acquires a deterioration evaluation value of each of the storage batteries after the low-capacity battery is set, and releases the low-capacity battery setting when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined release condition; A battery control system comprising:

2. The battery control system according to claim 1 , wherein the setting cancellation unit cancels the setting of the low-capacity battery when a difference between a deterioration evaluation value of each of the operational batteries and a deterioration evaluation value of the low-capacity battery falls within a predetermined range.

3. a sharing adjustment rate setting unit that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries; a medium-term power command setting unit that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the setting cancellation unit cancels the settings for all of the low-capacity batteries; The battery control system according to claim 1 .

4. The battery control system of claim 3, wherein the sharing adjustment rate setting unit calculates a target deterioration evaluation value using the deterioration evaluation value of each of the storage batteries, and sets a sharing adjustment rate for each of the storage batteries such that the deterioration evaluation value of each of the storage batteries approaches the target deterioration evaluation value.

5. a sharing adjustment rate setting unit that calculates a target deterioration evaluation value using a deterioration evaluation value of each of the storage batteries, and sets a sharing adjustment rate for each of the storage batteries by multiplying an adjustment value that brings the deterioration evaluation value of each of the storage batteries closer to the target deterioration evaluation value by an adjustment gain that is set to a value greater than 1; a medium-term power command setting unit that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the setting cancellation unit cancels the settings for all of the low-capacity batteries; The battery control system according to claim 4 .

6. a sharing adjustment rate setting unit that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries; A later-stage power command setting unit that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the battery system satisfies a preset later-stage operation condition; The battery control system according to claim 1 .

7. a sharing adjustment rate setting unit that calculates a target deterioration evaluation value using a deterioration evaluation value of each of the storage batteries, and sets a sharing adjustment rate for each of the storage batteries by multiplying an adjustment value that brings the deterioration evaluation value of each of the storage batteries closer to the target deterioration evaluation value by an adjustment gain; a medium-term power command setting unit that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the setting cancellation unit cancels the settings for all of the low-capacity batteries; A later-stage power command setting unit that sets individual power commands for each of the storage batteries using the sharing adjustment rate after the battery system satisfies a preset later-stage operation condition; Equipped with 3. The battery control system of claim 2, wherein the sharing adjustment rate setting unit sets the sharing adjustment rate used in the mid-term power command setting unit by using an adjustment gain greater than 1, and sets the sharing adjustment rate used in the later-term power command setting unit by using an adjustment gain set to 1.

8. an individual offset power setting unit that calculates an individual offset power for each of the storage batteries using charging rate data of each of the storage batteries; A later-stage power command setting unit that sets an individual power command for each of the storage batteries using an individual offset power for each of the storage batteries after the battery system satisfies a preset later-stage operation condition; Equipped with The individual offset power setting unit an individual average calculation unit that calculates an individual average charging rate for each of the storage batteries using charging rate data for each of the storage batteries during a predetermined period; an overall average calculation unit that calculates an overall average charging rate that is a reference for the entire battery system; an offset calculation unit that calculates, for each of the storage batteries, an individual offset power for bringing the individual average charging rate closer to the overall average charging rate; The battery control system according to claim 1 .

9. a sharing adjustment rate setting unit that sets a sharing adjustment rate using a deterioration evaluation value of each of the storage batteries; an individual offset power setting unit that calculates an individual offset power for each of the storage batteries using charging rate data of each of the storage batteries; A later-stage power command setting unit that sets an individual power command for each of the storage batteries using the individual offset power and the sharing adjustment rate for each of the storage batteries after the battery system satisfies a preset later-stage operation condition; Equipped with The individual offset power setting unit an individual average calculation unit that calculates an individual average charging rate for each of the storage batteries using charging rate data for each of the storage batteries during a predetermined period; an overall average calculation unit that calculates an overall average charging rate that is a reference for the entire battery system; an offset calculation unit that calculates, for each of the storage batteries, an individual offset power for bringing the individual average charging rate closer to the overall average charging rate; The battery control system according to claim 1 .

10. an overall offset power setting unit that calculates an overall offset power for correcting the system required power; a system required power correction unit that corrects a system required power of the battery system using the total offset power; A later-stage power command setting unit that sets individual power commands for each of the storage batteries using the corrected system required power after the battery system satisfies a preset later-stage operation condition; Equipped with The entire offset power setting unit an overall average calculation unit that calculates an overall average charging rate, which is an average charging rate of the battery system, using charging rate data of the battery system for a predetermined period; an offset calculation unit that calculates an overall offset power for making the overall average charging rate approach a predetermined reference charging rate; The battery control system according to claim 1 .

11. an overall offset power setting unit that calculates an overall offset power for correcting the system required power; a system required power correction unit that corrects a system required power of the battery system using the total offset power; A later-stage power command setting unit that sets individual power commands for each of the storage batteries using the corrected system required power after the battery system satisfies a preset later-stage operation condition; Equipped with The entire offset power setting unit a representative charging rate determination unit that determines an upper limit representative charging rate and a lower limit representative charging rate of the battery system using charging rate data of the battery system during a predetermined period; an offset calculation unit that calculates a total offset power for bringing a difference between a difference between the upper limit representative charging rate and a permissible upper limit value of the charging rate and a difference between the lower limit representative charging rate and a permissible lower limit value of the charging rate closer to zero; The battery control system according to claim 1 .

12. A battery system including a plurality of storage batteries; A battery control system according to any one of claims 1 to 11, An electricity supply and demand system comprising:

13. A battery control method applied to a battery system including a plurality of storage batteries, setting a low-capacity battery to be used less frequently based on a deterioration evaluation value related to a full charge capacity of each of the storage batteries at the start of the battery system; setting an individual power command for the storage battery so as to reduce the frequency of use of the low-capacity battery compared to an operational battery that is a storage battery other than the low-capacity battery; acquiring a deterioration evaluation value of each of the storage batteries after the low-capacity battery has been set, and releasing the low-capacity battery setting when the acquired deterioration evaluation value of each of the storage batteries satisfies a predetermined release condition; The computer executes the battery control method.

14. A battery control program for causing a computer to function as the battery control system according to any one of claims 1 to 11.

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