JP7588045B2 - CONTROLLER, CONTROL PROGRAM, CONTROL METHOD, AND POWER SUPPLY SYSTEM - Google Patents

Description

The present invention relates to a controller, a control program, a control method, and a power supply system.

For example, Patent Document 1 discloses a method for controlling charging and discharging power so that the power conversion efficiency of each of multiple power conversion devices connected to a storage battery is increased.

JP 2020-137131 A

The charge/discharge efficiency of the storage battery also changes depending on the charge/discharge power. By only looking at the power conversion efficiency of the power conversion device, as in Patent Document 1, it may not be possible to optimize the overall efficiency of the charge/discharge efficiency of the storage battery and the power conversion efficiency of the power conversion device.

The present invention aims to optimize the overall efficiency of the charge/discharge efficiency of the storage battery and the power conversion efficiency of the power conversion device.

A controller according to one aspect is a controller that controls the charging and discharging of each of a plurality of storage battery systems in accordance with at least one operating objective, each of the plurality of storage battery systems including a storage battery and a power conversion device connected to the storage battery, and the at least one operating objective includes a first operating objective of charging and discharging each of the plurality of storage battery systems so that the operating efficiency of each of the plurality of storage battery systems is high, and the operating efficiency is the overall efficiency of the charging and discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to the charging and discharging power.

A control program according to one aspect causes a computer to execute processing for controlling the charging and discharging of each of a plurality of storage battery systems in accordance with at least one operating objective, each of the plurality of storage battery systems including a storage battery and a power conversion device connected to the storage battery, and the at least one operating objective includes a first operating objective of charging and discharging each of the plurality of storage battery systems so that the operating efficiency of each of the plurality of storage battery systems is high, and the operating efficiency is the overall efficiency of the charging and discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to the charging and discharging power.

A control method according to one aspect is a control method for controlling the charging and discharging of each of a plurality of storage battery systems in accordance with at least one operating objective, each of the plurality of storage battery systems including a storage battery and a power conversion device connected to the storage battery, the at least one operating objective including a first operating objective of charging and discharging each of the plurality of storage battery systems so that the operating efficiency of each of the plurality of storage battery systems is high, and the operating efficiency is the overall efficiency of the charging and discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to the charging and discharging power.

A power supply system according to one aspect includes a plurality of storage battery systems and a controller that controls charging and discharging of each of the plurality of storage battery systems according to at least one operating objective, each of the plurality of storage battery systems including a storage battery and a power conversion device connected to the storage battery, and the at least one operating objective includes a first operating objective of charging and discharging each of the plurality of storage battery systems so that the operating efficiency of each of the plurality of storage battery systems is high, and the operating efficiency is the overall efficiency of the charging and discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to the charging and discharging power.

The present invention makes it possible to optimize the overall efficiency of the charge/discharge efficiency of the storage battery and the power conversion efficiency of the power conversion device.

1 is a diagram illustrating an example of a schematic configuration of a power supply system 100 in which a controller 4 according to an embodiment is used. FIG. 4 is a diagram showing an example of system data 444. A figure showing an example of system data 444 for each of multiple storage battery systems 2. A figure showing an example of system data 444 for each of multiple storage battery systems 2. A figure showing an example of system data 444 for each of multiple storage battery systems 2. A figure showing an example of system data 444 for each of multiple storage battery systems 2. 4 is a flowchart illustrating an example of a process executed in the power supply system 100. FIG. 2 illustrates an example of a hardware configuration of a controller. 1 is a diagram showing an example of a schematic configuration of a power supply system 100 in which a controller 4 according to a first application example is used. FIG. 2 is a diagram showing an example of power PG of a power generation device G. 11 is a diagram showing an example of a target value of power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of the total power (target value of PG+P1) of the target values of the power PG of the power generation device G and the power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of a target value of power P2 of the storage battery 21. FIG. FIG. 13 is a diagram showing an example of power P3 at collaboration point 3. 1 is a diagram showing an example of power P1 of a storage battery 11 and an example of a charge/discharge power amount. 11 is a diagram showing an example of power P2 of the storage battery 21 and an example of the amount of charge and discharge power. FIG. FIG. 1 is a diagram showing a schematic configuration of a comparative example. FIG. 13 is a diagram illustrating an example of power P3E in a comparative example. 11 is a diagram showing an example of power P2E and charge/discharge power amount of a storage battery 21E of a comparative example. FIG. 11 is a diagram showing an example of a target value of power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of the total power (target value of PG+P1) of the target values of the power PG of the power generation device G and the power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of a target value of power P2 of the storage battery 21. FIG. FIG. 13 is a diagram showing an example of power P3 at collaboration point 3. 1 is a diagram showing an example of power P1 of a storage battery 11 and an example of a charge/discharge power amount. 11 is a diagram showing an example of power P2 of the storage battery 21 and an example of the amount of charge and discharge power. FIG. FIG. 13 is a diagram showing an example of calculation of a target value of power P1 based on averaged power PG. 11 is a diagram showing an example of the total power (target value of PG+P1) of the target values of the power PG of the power generation device G and the power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of a target value of power P2 of the storage battery 21. FIG. FIG. 13 is a diagram showing an example of power P3 at collaboration point 3. 1 is a diagram showing an example of power P1 of a storage battery 11 and an example of a charge/discharge power amount. 11 is a diagram showing an example of power P2 of the storage battery 21 and an example of the amount of charge and discharge power. FIG. FIG. 11 is a diagram showing an example of a shift in power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of a shift in power P1 of the storage battery 11. FIG. 11 is a diagram showing an example of a schematic configuration of a power supply system 100A in which a controller 4A according to a second application example is used. 11 is a diagram showing an example of a plan for a target value of power P1 of the storage battery 11. FIG. 1 is a diagram showing an example of a load, which is connected to a power line W and consumes power from the power line W and is referred to as a load L. FIG. 13 is a diagram illustrating an example of a schematic configuration of a controller 4B according to a modified example.

The following describes the embodiments with reference to the drawings. The same elements, functions, processes, etc. are designated by the same reference numerals, and duplicate descriptions are omitted as appropriate.

Figure 1 is a diagram showing an example of the schematic configuration of a power supply system 100 in which a controller 4 according to an embodiment is used. The power supply system 100 includes a plurality of storage battery systems 2, a connection point 3, a controller 4, a power line W, and a power line W2.

First, the power line W, the power line W2, and the connection point 3 will be described. The power line W and the power line W2 connect the multiple storage battery systems 2 to the connection point 3. The power line W2 is connected between the multiple storage battery systems 2 and the power line W. Unless otherwise specified, the power line W and the power line W2 are assumed to be AC power lines. AC power refers to active power. For convenience, the power line W2 is illustrated and described as a power line bundling the multiple storage battery systems 2. The power line W2 may be omitted, in which case the power line W connects the storage battery systems 2 to the connection point 3.

The connection point 3 is a connection point between the power line W and the power grid 9. Electric power is exchanged between the storage battery system 2 and the power grid 9 via the connection point 3. An example of the power grid 9 is a commercial power grid (commercial system), and in this case, the power supply system 100 may operate in cooperation with the power grid 9.

The multiple storage battery systems 2 are connected in parallel to each other when viewed from the power line W, more specifically, from the power line W2. In order to distinguish between the multiple storage battery systems 2, they are illustrated as storage battery system 2-1, storage battery system 2-2, storage battery system 2-3, and storage battery system 2-n. Note that the number of multiple storage battery systems 2 may be two or more, and therefore n may be an integer of two or more.

The storage battery system 2 includes a storage battery 21, a PCS 22, terminals 23, and a battery controller 24. In order to distinguish between the storage batteries 21 of each of the multiple storage battery systems 2, they are illustrated as storage battery 21-1, storage battery 21-2, storage battery 21-3, and storage battery 21-n. The same is true for the PCS 22, terminals 23, and battery controller 24.

The storage battery 21 charges and discharges between the power line W2 and the power line W via the PCS 22. The PCS 22 is a power conversion device that is connected to the storage battery 21 and charges and discharges the storage battery 21. More specifically, the PCS 22 is a bidirectional power conversion device that converts the power from the storage battery 21 into AC power and supplies it to the power line W2, and converts the AC power from the power line W2 into DC power and supplies it to the storage battery 21. The PCS 22 is also called a Power Conditioning System, Power Converter, etc.

The charging and discharging power of the storage battery 21 via the PCS 22 is illustrated and referred to as power p. With respect to power p, the discharged power is assumed to be positive. The power p of the storage battery system 2-1, storage battery system 2-2, storage battery system 2-3, and storage battery system 2-n is illustrated and referred to as power p-1, power p-2, power p-3, and power p-n.

The power p of each of the multiple storage battery systems 2 is combined by the power line W2. The power combined by the power line W2 is referred to as power P2 and illustrated. The discharge power of power P2 is also assumed to be positive. Power P2 is the total power of power p-1 to power p-n. Hereinafter, the power p of each of the multiple storage battery systems 2 is also referred to as "each power p."

The terminal 23 is an output terminal of the storage battery system 1, and provides a connection between the PCS 22 and the power line W. The battery controller 24 controls the charging and discharging of the storage battery 21 by controlling the PCS 22. For example, the battery controller 24 provides an output command value to the PCS 22. The output command value specifies, for example, the magnitude and direction (charging or discharging) of the power p. In addition, the battery controller 24 monitors the power p at the terminal 23, and monitors the SOC (State Of Charge) and remaining capacity of the storage battery 21. The battery controller 24 is configured to be able to communicate with the controller 4. An example of the unit of the SOC is %, and an example of the unit of the remaining capacity is Ah, Wh, etc. Hereinafter, the SOC and remaining capacity may be interpreted as appropriate within the scope of no contradiction, and one of the SOC and remaining capacity may be interpreted as including the other.

The controller 4 controls the charging and discharging of each of the multiple storage battery systems 2 according to the operation purpose of the power supply system 100. The controller 4 includes an acquisition unit 41, a calculation unit 42, a charge and discharge control unit 43, and a memory unit 44.

The acquisition unit 41 acquires information necessary for charge/discharge control of the storage battery system 2. For example, the acquisition unit 41 acquires power information. An example of the power information is a power value, etc., which is measured, monitored, etc. by a power measuring device (not shown). An example of the power is the power p of the storage battery system 2. For example, the information on the power p is transmitted from the battery controller 24 of the storage battery system 2 to the controller 4 and acquired by the acquisition unit 41.

The acquisition unit 41 also acquires storage battery information. Examples of storage battery information are the remaining capacity and power price of the storage battery 21. The remaining capacity is referred to as the remaining capacity Q, and the power price is referred to as the power price C. The remaining capacity Q is transmitted from the battery controller 24 to the controller 4 and acquired by the acquisition unit 41. The power price C is the price of the power (power corresponding to the remaining capacity Q) charged to the storage battery 21. For example, the power price C may be the power price (e.g., the electricity rate) during the time period during which the storage battery 21 is charged. When the storage battery 21 is charged during multiple time periods with different power prices, the price obtained by weighting and averaging the respective power prices with the corresponding charging power amount may be used as the power price C. The power price C may be calculated by the battery controller 24 or the controller 4. The power price C calculated by the battery controller 24, or information such as the charging time period on which the power price C is calculated, is transmitted from the battery controller 24 to the controller 4 and acquired by the acquisition unit 41.

The calculation unit 42 calculates the target value of each power p based on the target value of the power P2. The target value of the power P2 may be provided from outside the controller 4 or may be calculated within the calculation unit 42. Details of the calculation by the calculation unit 42 will be described later.

The charge/discharge control unit 43 controls the charging and discharging of each of the multiple storage battery systems 2 based on the target value of each power p calculated by the calculation unit 42. For example, the charge/discharge control unit 43 transmits an output command value of the PCS 22 corresponding to the target value of the power p to the battery controller 24. The battery controller 24 provides the received output command value to the PCS 22. The PCS 22 charges and discharges the storage battery 21 according to the provided output command value. The power p of the storage battery system 2 approaches the target value.

The memory unit 44 stores various information necessary for control by the controller 4. Examples of information stored in the memory unit 44 include a control program 441 and system data 444. The control program 441 is a program that causes a computer to execute the control (processing) executed by the controller 4. The system data 444 is data related to the storage battery system 2. The system data 444 will be described with reference to Figures 2 to 6.

2 is a diagram showing an example of the system data 444. In this example, the system data 444 describes the storage battery system 2, an efficiency function E(p), a remaining capacity Q, and an electricity price C in association with each other. The efficiency functions E(p) of the storage battery system 2-1, the storage battery system 2-2, the storage battery system 2-3, and the storage battery system 2-n are referred to as efficiency function E ₁ (p), efficiency function E ₂ (p), efficiency function E ₃ (p), and efficiency function E _n (p). The same applies to the remaining capacity Q and the electricity price C.

The efficiency function E(p) is a function that takes the power p of the storage battery system 2 as an argument and the operation efficiency E of the storage battery system 2 as a return value. The operation efficiency E is the overall efficiency of the charge/discharge efficiency of the storage battery 21 and the power conversion efficiency of the PCS 22 with respect to the charge/discharge power of the storage battery system 2. If the charge/discharge efficiency of the storage battery 21 at a certain power p is η _bat and the power conversion efficiency of the PCS 22 is η _pcs , the operation efficiency E at that power p is expressed as the product of the charge/discharge efficiency η _bat and the power conversion efficiency η _pcs , as shown in the following formula (1). When the efficiency differs between charging and discharging, each variable may be separated.

The remaining capacity Q and the electricity price C are as explained above. The efficiency function E(p), remaining capacity Q, and electricity price C may differ for each of the multiple storage battery systems 2. This will be explained with reference to Figures 3 to 6.

Figures 3 to 6 are diagrams showing examples of system data 444 for each of multiple storage battery systems 2. Figures 3, 4, 5, and 6 show examples of system data 444 for storage battery system 2-1, storage battery system 2-2, storage battery system 2-3, and storage battery system 2-n. In each figure, (A) shows a schematic representation of the efficiency function E(p), and (B) shows a schematic representation of the remaining capacity Q and the power price C.

3 to 6A, the operating region including the peak position where the operating efficiency E with respect to the power p (magnitude) is maximum is surrounded by a dashed line. As can be understood, the peak position of the operating efficiency of each of the multiple storage battery systems 2 may differ from each other. This is because the peak positions of the charge and discharge efficiency of the storage batteries 21 of each of the multiple storage battery systems 2 may differ, or the peak positions of the power conversion efficiency of each PCS 22 may differ. Examples of factors that cause differences in the peak positions of the charge and discharge efficiency of the storage batteries 21 include cases where the design (model number, etc.) of the storage batteries 21 is different, or cases where the period of use (start of operation, etc.) is different. If the design is different, the charge and discharge efficiency characteristics indicating the charge and discharge efficiency with respect to the charge and discharge power may differ. If the period of use is different, the degree of deterioration of the storage batteries 21, etc. will differ, and therefore the charge and discharge efficiency characteristics may differ. The same can be said for the PCS 22.

Of the illustrated storage battery systems 2, the magnitude of power p corresponding to the peak position of storage battery system 2-1 is the largest, and the magnitude of power p corresponding to the peak position of storage battery system 2-2 is the smallest. The magnitudes of power p corresponding to the peak positions of storage battery system 2-3 and storage battery system 2-n are between them. When the magnitude of power p of storage battery system 2 is zero, the PCS 22 of storage battery system 2 is stopped, and power consumption is minimized. The position where the magnitude of power p is zero may also be treated as a peak position. In this case, control of the number of storage battery systems 2 that perform charging and discharging (unit number control) is also included in the charge and discharge control of storage battery system 2.

3 to 6B, the remaining capacity Q of each of the multiple storage battery systems 2 may differ from one another. The same applies to the electricity price C. Among the illustrated storage battery systems 2, the remaining capacity _Q1 of storage battery system 2-1 is the largest (e.g., SOC 100%), and the remaining capacity _Qn of storage battery system 2-n is the smallest (e.g., SOC 20%). The remaining capacity Q2 of storage battery system 2-2 and the remaining capacity Q3 of storage battery system 2-3 are between them (e.g., SOC 50% and SOC 70%).

Returning to FIG. 1, part of the system data 444 is generated in advance and stored in the storage unit 44, and the rest is generated, acquired, etc., as appropriate and stored in the storage unit 44. For example, an initial efficiency function E(p) of the battery system 2 is generated in advance and stored in the storage unit 44. Since the efficiency function E(p) may change depending on the period of use of the battery system 2, etc., the efficiency function E(p) may be updated as appropriate. The remaining capacity Q and the electricity price C are acquired by the acquisition unit 41 and stored in the storage unit 44.

In addition, the memory unit 44 stores various information related to the acquisition by the acquisition unit 41 and the calculation by the calculation unit 42.

The calculation unit 42 will be described in detail. The calculation unit 42 calculates the target value of each power p based on the target value of power P2 and the system data 444. The calculation unit 42 calculates the target value of each power p so that the sum of the target values of each power p is equal to the target value of power P2. In this embodiment, the target value of each power p is calculated according to at least one operation objective. The following describes three operation objectives as examples.

The first operating objective includes charging and discharging each of the multiple storage battery systems 2 so that the operating efficiency E of each of the multiple storage battery systems 2 is high. The first operating objective can be adopted both during charging (the target value of power P2 is positive) and during discharging (the target value of power P2 is negative). For example, the calculation unit 42 calculates the target value of each power p so that the operating efficiency E of each of the multiple storage battery systems 2 approaches a peak position. By controlling charging and discharging in accordance with the first operating objective, the operating efficiency E of each of the multiple storage battery systems 2 can be optimized.

The second operation objective includes giving priority to discharging the storage battery 21 with a large remaining capacity Q among the storage batteries 21 of each of the multiple storage battery systems 2, and giving priority to charging the storage battery 21 with a small remaining capacity Q. The second operation objective can be adopted both during charging and discharging. For example, during discharging, the calculation unit 42 calculates the target value of each power p so that the power p of the storage battery 21 with a large remaining capacity Q (i.e., small free capacity) is larger than the power p of the other storage batteries 21. During charging, the calculation unit 42 calculates the target value of each power p so that the power p of the storage battery 21 with a small remaining capacity Q (i.e., large free capacity) is larger than the power p of the other storage batteries 21. The difference in the remaining capacity Q of each storage battery 21 can be reduced (balanced) by the charge/discharge control according to the second operation objective. Since the remaining capacity Q of each storage battery 21 can be brought to approximately SOC 50% as a result, a capacity that can be handled even if the subsequent operation is charging or discharging can be secured.

The third operating objective includes giving priority to discharging the storage batteries 21 with a low (cheap) price of charged electricity among the storage batteries 21 in each of the multiple storage battery systems 2. The third operating objective can be adopted only during discharging, out of charging and discharging. For example, the calculation unit 42 calculates the target value of each power p so that the power p of the storage battery 21 charged with electricity with a low power price C is greater than the power p of the other storage batteries 21. By controlling charging and discharging in accordance with the third operating objective, it is possible to give priority to supplying electricity with a low power price C, while conserving as much electricity with a high power price C as possible in the storage batteries 21. Benefits such as saving electricity costs can be obtained.

In one embodiment, a judgment value D is used. The judgment value D is a value (score) indicating the degree of reflection of at least one driving purpose. When multiple driving purposes are taken into consideration, the judgment value D indicates the degree of each of the multiple driving purposes, each of which is weighted. The calculation unit 42 calculates the target value of each power p so that the judgment value D becomes the largest (so that the score is maximized). The judgment value D used during discharging and charging may differ. Below, the explanation will be given in the order of discharging and charging. Note that the judgment formula shown below is an example.

The judgment value D used during discharge is referred to as judgment value D1. The judgment value D1 is determined so that the greater the operating efficiency E of the storage battery system 2, the greater the judgment value D1. The judgment value D1 is also determined so that the greater the remaining capacity Q, the greater the judgment value D1. The judgment value D1 is also determined so that the lower the electricity price C, the greater the judgment value D1.

上記の式（２）の左辺は、判定値Ｄ１である。右辺において、ｐ_ｋは、ｋ番目の蓄電池システム２の電力ｐの目標値である。Ｅ_ｋ（Ｐ_ｋ）は、ｋ番目の蓄電池システム２の効率関数Ｅ（ｐ）である。Ｑ_ｋは、ｋ番目の蓄電池システム２の蓄電池２１の残存容量Ｑである。Ｃ_ｋは、ｋ番目の蓄電池システム２の蓄電池２１に充電されている電力の電力価格Ｃである。係数Ｋ_ｅは、効率関数Ｅ（ｐ）の重み付け係数である。係数Ｋ_ｑは、残存容量Ｑの重み付け係数である。係数Ｋ_ｃは、電力価格Ｃの重み付け係数である。 For example, the calculation unit 42 calculates each power p so that the determination value D1 given by the following formula (2) is maximized and formula (3) is satisfied.

The left side of the above equation (2) is the judgment value D1. On the right side, _pk is the target value of the power p of the kth storage battery system 2. _Ek ( _Pk ) is the efficiency function E(p) of the kth storage battery system 2. _Qk is the remaining capacity Q of the storage battery 21 of the kth storage battery system 2. _Ck is the electricity price C of the electricity charged to the storage battery 21 of the kth storage battery system 2. The coefficient _Ke is a weighting coefficient for the efficiency function E(p). The coefficient _Kq is a weighting coefficient for the remaining capacity Q. The coefficient _Kc is a weighting coefficient for the electricity price C.

The larger the coefficient K _e is, the larger the proportion of the operational efficiency E in the judgment value D1 becomes, and the weight of the first operational objective becomes greater. The larger the coefficient K _q is, the larger the proportion of the remaining capacity Q in the judgment value D1 becomes, and the weight of the second operational objective (here, the second operational objective during discharging) becomes greater. The smaller the coefficient K _c is, the larger the proportion of the reciprocal of the power price C in the judgment value D1, i.e., the proportion of supplying power with a low power price C, becomes, and the weight of the third operational objective becomes greater.

When the judgment value D1 indicates only the degree of reflection of the first operating objective, the right-hand side of the above formula (2) may be described only with terms related to the efficiency function E(p). Similarly, in the case of the second operating objective, it may be described only with terms related to the remaining capacity Q. In the case of the third operating objective, it may be described only with terms related to the electricity price C.

The left side of the above equation (3) is the target value for power P2. The right side is the sum of the target values for each power p.

On the other hand, the judgment value D used during charging is referred to as judgment value D2. The judgment value D2 is set so that the judgment value D2 increases as the operating efficiency E of the storage battery system 2 increases. The judgment value D2 is also set so that the judgment value D2 increases as the remaining capacity Q decreases.

上記の式（４）の左辺は、判定値Ｄ２である。右辺は、先に説明した式（２）と比較して、電力価格Ｃに関する項が無い点、及び、残存容量Ｑに関する項が逆数となっている点において相違する。係数Ｋ_ｅを大きくするほど、判定値Ｄ２に占める動作効率Ｅの割合が大きくなり、第１の運転目的の重みが大きくなる。係数Ｋ_ｑを大きくするほど、判定値Ｄ２に占める残存容量Ｑの逆数（つまり空き容量）の割合が小さくなり、第２の運転目的（ここでは充電時の目標）の重みが大きくなる。 For example, the calculation unit 42 calculates each power p so that the judgment value D2 given by the following formula (4) is maximized and the above-mentioned formula (3) is satisfied.

The left side of the above formula (4) is the judgment value D2. The right side differs from the previously described formula (2) in that there is no term related to the power price C, and the term related to the remaining capacity Q is an inverse. The larger the coefficient K _e is, the larger the proportion of the operation efficiency E in the judgment value D2 becomes, and the weight of the first operation objective becomes greater. The larger the coefficient K _q is, the smaller the proportion of the inverse of the remaining capacity Q (i.e., available capacity) in the judgment value D2 becomes, and the weight of the second operation objective (here, the target during charging) becomes greater.

When the judgment value D2 indicates only the degree of reflection of the first driving objective, the right-hand side of the above formula (4) may be described only in terms related to the efficiency function E(p). Similarly, in the case of the second driving objective, it may be described only in terms related to the remaining capacity Q.

As mentioned above, the above formulas (2) to (4) are merely examples of formulas for calculating the judgment value D1 and the judgment value D2. Various formulas that can give the judgment value D1 and the judgment value D2 may be used as long as they do not deviate from the spirit of the judgment value D1 and the judgment value D2.

Returning to FIG. 1, for example, the calculation unit 42 calculates each power p according to at least one operation purpose in the above manner. The operation purpose is set manually or automatically, and is acquired by, for example, the acquisition unit 41. A plurality of operation purposes may be set together with priorities (corresponding to weighting). In this case, the calculation unit 42 calculates the target value of each power p2 after adjusting the coefficients K _e , K _q , and K _c according to the priorities. The higher the priority, the larger the corresponding weighting coefficient is adjusted. The charge/discharge control unit 43 controls the charge/discharge of each of the plurality of storage battery systems 2 based on each power p calculated by the calculation unit 42, i.e., according to at least one operation purpose. When the judgment value D is used, the charge/discharge control unit 43 controls the charge/discharge of each of the plurality of storage battery systems 2 so that, for example, the above-mentioned judgment value D1 or judgment value D2 is maximized.

Figure 7 is a flowchart showing an example of a process (control method) executed by the controller 4. The process of this flowchart is started in response to a target value of power P2 being given.

In step S1, it is determined whether discharging or charging is occurring. For example, the calculation unit 42 of the controller 4 determines that discharging is occurring when the target value of power P2 is positive, and determines that charging is occurring when the target value of power P2 is negative. If discharging is occurring (step S1: Yes), processing proceeds to step S2. If not, i.e., if charging is occurring (step S1: No), processing proceeds to step S4.

In step S2, the coefficients of the judgment value D1 are adjusted. The calculation unit 42 of the controller 4 adjusts the coefficients K _e , K _q , and K _c in the above-mentioned formula (2) in accordance with the priorities of the first driving objective, the second driving objective, and the third driving objective.

In step S3, the target value of each power p is calculated. The calculation unit 42 of the controller 4 calculates the target value of each power p so that the judgment value D1, the coefficient of which was adjusted in the previous step S2, is maximized. After the processing of step S3 is completed, the process proceeds to step S6.

In step S4, the coefficient of the determination value D2 is adjusted. The calculation unit 42 of the controller 4 adjusts the coefficients K _e and K _q in the above-mentioned formula (4) in accordance with the priorities of the first driving objective and the second driving objective.

In step S5, the target value of each power p is calculated. The calculation unit 42 of the controller 4 calculates the target value of each power p so that the judgment value D2, the coefficient of which was adjusted in the previous step S4, is maximized. After the processing of step S5 is completed, the process proceeds to step S6.

In step S6, charge and discharge control is performed. The charge and discharge control unit 43 of the controller 4 controls the charge and discharge of each of the multiple storage battery systems 2 based on the target value of each power p calculated in the previous step S3 or step S5.

Figure 8 is a diagram showing an example of the hardware configuration of a controller. A computer or the like having the illustrated hardware configuration functions as the controller 4 described above. The controller 4 has, as its hardware configuration, a communication device 4a, a display device 4b, a HDD (Hard Disk Drive) 4c, a memory 4d, and a processor 4e, all of which are interconnected by a bus or the like.

The communication device 4a is a network interface card or the like, and enables communication with other devices. The display device 4b is, for example, a touch panel or a display. The HDD 4c functions as a storage unit 44, and stores, for example, a control program 441.

The processor 4e reads the control program 441 from the HDD 4c or the like and loads it into the memory 4d, causing the computer to function as the controller 4. The functions of the controller 4 include the functions of the acquisition unit 41, the calculation unit 42, and the charge/discharge control unit 43, as described above.

The control program 441 can be distributed via a network such as the Internet. In addition, the control program 441 can be recorded on a computer-readable recording medium such as a hard disk, a flexible disk (FD), a CD-ROM, an MO (Magneto-Optical disk), or a DVD (Digital Versatile Disc), and can be executed by being read from the recording medium by a computer.

As described above, the controller 4 controls charging and discharging of each of the multiple storage battery systems 2 in accordance with at least one operation objective. Each of the multiple storage battery systems 2 includes a storage battery 21 and a PCS 22 (power conversion device) connected to the storage battery 21. The at least one operation objective includes a first operation objective of charging and discharging each of the multiple storage battery systems 2 so that the operation efficiency E of each of the multiple storage battery systems 2 is high. The operation efficiency E is the overall efficiency of the charge and discharge efficiency η _bat of the storage battery 21 and the power conversion efficiency η _pcs of the PCS 22 with respect to power p (charge and discharge power).

According to the controller 4 described above, the charging and discharging of the multiple storage battery systems 2 is controlled so as to increase the operation efficiency E of each of the multiple storage battery systems 2. Therefore, it is possible to optimize the overall efficiency, including the charging and discharging efficiency η _bat of the storage batteries 21 and the power conversion efficiency η _pcs of the PCS 22 (power conversion device).

As described with reference to Figures 2 to 6, the peak positions of the operating efficiency E of each of the multiple storage battery systems 2 are different from each other, and the first operation objective may include bringing the operating efficiency E of each of the multiple storage battery systems 2 closer to the peak position. For example, in this manner, the operating efficiency E of each of the multiple storage battery systems 2 can be optimized.

The peak positions of the charge/discharge efficiency η _bat of the storage batteries 21 of the multiple storage battery systems 2 may be different from each other. For example, the peak positions of the charge/discharge efficiency η _bat may be different from each other due to differences in the design and period of use of the storage batteries 21 of the multiple storage battery systems 2. It is possible to optimize the operation efficiency E of the multiple storage battery systems 2 each including storage batteries 21 with different designs and periods of use. For example, it is possible to flexibly respond to addition or replacement of the storage battery system 2.

At least one of the operating objectives may further include a second operating objective of preferentially discharging the storage battery 21 with a larger remaining capacity Q among the storage batteries 21 in each of the multiple storage battery systems 2 and preferentially charging the storage battery 21 with a smaller remaining capacity Q. By controlling charging and discharging according to the second operating objective, the remaining capacities Q of the storage batteries 21 can be brought closer together (balanced).

The at least one operating objective may further include a third operating objective of preferentially discharging the storage battery 21 with a low price of charged electricity (electricity price C) among the storage batteries 21 in each of the multiple storage battery systems 2. By controlling charging and discharging in accordance with the third operating objective, it is possible to preferentially supply electricity with a low electricity price C, while conserving electricity with a high electricity price C as much as possible in the storage battery 21. This provides benefits such as saving electricity costs.

The controller 4 may control the charging and discharging of each of the multiple storage battery systems 2 so that a judgment value D (judgment value D1 or judgment value D2) indicating the degree of reflection of at least one driving purpose becomes large. The judgment value D may indicate the degree of multiple driving purposes, each of which is weighted. For example, by using such a judgment value D, charging and discharging control according to the driving purpose can be performed.

The control program 441 described with reference to FIG. 1 and the like is also one of the disclosed techniques. The control program 441 causes a computer to execute a process of controlling the charging and discharging of each of the multiple storage battery systems 2 according to at least one operating purpose (including the first operating purpose). The control method described with reference to FIG. 7 and the like is also one of the disclosed techniques. The control method controls the charging and discharging of each of the multiple storage battery systems 2 according to at least one operating purpose (including the first operating purpose) (step S6). The power supply system 100 described with reference to FIG. 1 and the like is also one of the disclosed techniques. The power supply system 100 includes multiple storage battery systems 2 and a controller 4 that controls the charging and discharging of each of the multiple storage battery systems 2 according to at least one operating purpose (including the first operating purpose). As described above, the control program 441, the control method, and the power supply system 100 can also optimize the overall efficiency of the charging and discharging efficiency η _bat of the storage battery 21 and the power conversion efficiency η _pcs of the PCS 22.

<Application Examples>
The multiple storage battery systems 2 described above are used, for example, for power smoothing. In that case, the multiple storage battery systems 2 may be used in combination with another storage battery system. The controller 4 may control the charging and discharging of each of these storage battery systems. Hereinafter, the charging and discharging power of the storage battery systems described above may be simply referred to as the charging and discharging power of the storage batteries. The charging and discharging control of the storage battery system may be simply referred to as the charging and discharging control of the storage batteries.

<First Application Example>
FIG. 9 is a diagram showing an example of a schematic configuration of a power supply system 100 in which a controller 4 according to a first application example is used. The power supply system 100 further includes a power generation device G and a storage battery system 1. The multiple storage battery systems 2 are simply called storage battery systems 2 unless otherwise specified. The charging and discharging power of the storage battery 21 of the storage battery system 2 is the power P2 described above. The power line W connects the power generation device G, the storage battery system 1, and the storage battery system 2 to a connection point 3. Power is exchanged between the power generation device G, the storage battery system 1, and the storage battery system 2, and the power grid 9 via the connection point 3. The power exchanged at the connection point 3 is called power P3 and illustrated. In the power P3, the power toward the power grid 9 is assumed to be positive.

The power generation by the power generation device G includes power generation using natural energy. Examples of natural energy are wind energy and solar energy, and in that case, the power generation device G is composed of a wind power generation device, a solar power generation device, etc. The generated power of the power generation device G, more specifically, the power flowing from the power generation device G to the power line W, is referred to as power PG and illustrated.

Figure 10 is a diagram showing an example of the power PG of the power generation device G. The horizontal axis of the graph indicates time t, and the vertical axis of the graph indicates power (kW). The graph shows an example of the change in power PG over time during a certain time period. As shown in Figure 10, the generated power PG changes every moment.

The rate of change is used as an index to represent the change in power over time. The rate of change indicates the rate of change in the power value per unit period, and is expressed, for example, as the ratio (%) of the amount of change in the power value to the rated power (rated output) of the power generating device G. The unit period for the short-cycle stability target is generally one minute, and the rate of change is %/minute.

When only the power PG of the power generation device G is supplied to the power line W, the large rate of change of the power PG is directly reflected as the rate of change of the power P3 at the connection point 3. From the viewpoint of the stability of the power grid 9, it is necessary to suppress the rate of change of the power P3 at the connection point 3. Suppressing this rate of change, in other words, stabilizing the power generation device, is one of the purposes of the storage battery system 1 and the storage battery system 2.

Returning to FIG. 9, the storage battery system 1 includes a storage battery 11, a PCS 12, a terminal 13, and a battery controller 14. These elements are similar to the corresponding parts of the storage battery system 2, so detailed explanations are omitted. The charging and discharging power of the storage battery system 1 is referred to as power P1 and is illustrated. In the case of power P1, the discharging power is also positive.

Storage battery 11 and storage battery 21 are a first storage battery and a second storage battery having different characteristics. Storage battery 11 is a large-capacity storage battery, and storage battery 21 is a high-output storage battery. A large-capacity storage battery has the characteristic that it is easier to obtain a large amount of charge/discharge power (battery capacity) but it is difficult to obtain a large amount of charge/discharge power (output) compared to a high-output storage battery. A high-output storage battery has the characteristic that it is easier to obtain a large amount of charge/discharge power but it is difficult to obtain a large amount of charge/discharge power compared to a large-capacity storage battery. Since it is publicly known that storage batteries with these different characteristics exist, further detailed explanation is omitted.

The storage battery 11 has a battery capacity larger than that of the storage battery 21. The controller 4 controls the charging and discharging of the storage battery 11 and the storage battery 21 so that the maximum charging and discharging power (maximum output) of the storage battery 11 is smaller than the maximum charging and discharging power of the storage battery 21. Note that the maximum charging and discharging power of the storage battery 11 here indicates the maximum absolute value of the power P1. The maximum charging and discharging power of the storage battery 21 indicates the maximum absolute value of the power P2.

The controller 4 controls the charging and discharging of the storage battery 11 of the storage battery system 1 and the storage battery 21 of the storage battery system 2. The power information acquired by the acquisition unit 41 of the controller 4 includes the power PG of the power generation device G, the power P1 of the storage battery 11, the power P2 of the storage battery 21, the power P3 of the connection point 3, and the like. For example, the information on the power PG is transmitted from the power generation device G to the controller 4 and acquired by the acquisition unit 41. The information on the power P1 and the power P2 is transmitted from the battery controller 14 and the battery controller 24 to the controller 4 and acquired by the acquisition unit 41. The information on the power P3 is transmitted from the connection point 3 to the controller 4 and acquired by the acquisition unit 41. The battery information acquired by the acquisition unit 41 also includes the remaining capacity of the storage battery 11, and the like.

The calculation unit 42 calculates the target value of the power P1 of the storage battery 11 and the target value of the power P2 of the storage battery 21 based on the information acquired by the acquisition unit 41. Details will be described later.

The charge/discharge control unit 43 controls the charge/discharge of the storage battery 11 and the storage battery 21 based on the target value of the power P1 and the target value of the power P2 calculated by the calculation unit 42. For example, the charge/discharge control unit 43 transmits an output command value of the PCS 12 corresponding to the target value of the power P1 to the battery controller 14. The battery controller 14 provides the received output command value to the PCS 12. The PCS 12 charges and discharges the storage battery 11 according to the provided output command value. The power P1 of the storage battery 11 approaches the target value. The charge/discharge control unit 43 also transmits an output command value of the PCS 22 corresponding to the target value of the power P2 to the battery controller 24. The battery controller 24 provides the received output command value to the PCS 22. The PCS 22 charges and discharges the storage battery 21 according to the provided output command value. The power P2 of the storage battery 21 approaches the target value.

The charge/discharge control by the charge/discharge control unit 43 is performed at intervals of less than the unit period (such as one minute) of the rate of change described above. Examples of intervals for charge/discharge control are several seconds, tens of seconds, several tens of seconds, one minute, etc. The intervals for calculation by the calculation unit 42 may also be the same as the intervals for charge/discharge control.

The calculation unit 42 will be described in detail. The calculation unit 42 includes a first calculation unit 421 and a second calculation unit 422. The first calculation unit 421 calculates a target value of power P1. The second calculation unit 422 calculates a target value of power P2. The first calculation unit 421 and the second calculation unit 422 calculate the target value of power P1 and the target value of power P2 so as to suppress the rate of change of power P3 at the linkage point 3. In the following, it is assumed that the rate of change is suppressed to 1%/min or less.

The first calculation unit 421 calculates a target value for the power P1 so as to suppress the rate of change of the power P3 at the linkage point 3 within a range in which the magnitude of the power P1 does not exceed the set value. The set value is set to a value smaller than the maximum charge/discharge power of the storage battery 21. If the calculated target value of the power P1 exceeds the set value, the first calculation unit 421 calculates a power of the same magnitude as the set value as the target value of the power P1. As a result, the target value of the power P1 is limited (fixed) to the set value. The following describes an example in which the set value is 400 kW.

Figure 11 is a diagram showing an example of a target value for power P1 of the storage battery 11. The target value for power P1 is calculated so as to suppress the rate of change of power P3 within a range in which the magnitude of power P1 does not exceed 400 kW, i.e., within a range of power P1 of ±400 kW. If the calculated power P1 exceeds +400 kW, +400 kW is calculated as the target value for power P1. If the calculated power P1 falls below -400 kW, -400 kW is calculated as the target value for power P1.

Returning to FIG. 9, the second calculation unit 422 calculates the total power of the power PG and the target value of the power P1 calculated by the first calculation unit 421. This total power is the power P3 after the rate of change has been suppressed by the power P1, and corresponds to the power P3 when it is assumed that the power P2 of the storage battery 21 does not exist.

Figure 12 is a diagram showing an example of the total power (target value of PG+P1) of the power PG of the power generation device G and the target value of the power P1 of the storage battery 11. Compared to the original power PG (Figure 10), the rate of change is significantly suppressed. However, during the period when the target value of the power P1 is limited to the set value, the rate of change is still not sufficiently suppressed. In other words, the rate of change is not suppressed to 1%/min or less.

Returning to FIG. 9, the second calculation unit 422 calculates the target value of power P2 so as to further suppress the rate of change of the total power of power PG and the target value of power P1, i.e., the rate of change of power P3 after it has been suppressed by power P1.

Figure 13 is a diagram showing an example of a target value of the power P2 of the storage battery 21. The target value of the power P2 of the storage battery 21 is calculated so as to further suppress the rate of change in the period in which the rate of change was not sufficiently suppressed in Figure 12 described above.

Returning to FIG. 9, the calculation unit 42 calculates the target value of the power p (each power p) of each of the multiple storage battery systems 2 based on the target value of the power P2 calculated by the second calculation unit 422. The specific calculation method is as described above with reference to FIGS. 1 to 7, so a detailed description will not be repeated. In the following description, the target value of the power P2 may be interpreted as the sum of the target values of each power p, as appropriate.

The charge/discharge control unit 43 controls the charging and discharging of the storage battery 11 and the storage battery 21 based on the target value of the power P1 and the target value of the power P2 calculated by the calculation unit 42. That is, the charge/discharge control unit 43 charges and discharges the storage battery 11 and the storage battery 21 so that the maximum charge/discharge power of the storage battery 11 is smaller than the maximum charge/discharge power of the storage battery 21. More specifically, the charge/discharge control unit 43 charges and discharges the storage battery 11 so as to suppress the rate of change of the power P3 within a range in which the magnitude of the power P1 does not exceed a set value (a value smaller than the maximum charge/discharge power of the storage battery 21). Then, the charge/discharge control unit 43 charges and discharges the storage battery 21 so as to further suppress the rate of change of the power P3 after it has been suppressed by the storage battery 11.

Figure 14 is a diagram showing an example of power P3 at connection point 3. The rate of change of power P3 at any time t is suppressed by power P1 and power P2. In other words, the rate of change is suppressed to 1%/min or less.

The maximum charge/discharge power and battery capacity of each of the storage batteries 11 and 21 that are charge/discharge controlled as described above will be described with reference to Figures 15 and 16.

Figure 15 is a diagram showing an example of the power P1 and the charge/discharge power amount of the storage battery 11. The maximum charge/discharge power of the storage battery 11 is 400 kW because the power P1 is limited within the range of ±400 kW. The battery capacity required by the storage battery 11 is approximately 1500 kWh because the charge/discharge power amount varies between approximately +70 kWh and approximately -1430 kWh.

Figure 16 is a diagram showing an example of the power P2 and the charge/discharge power amount of the storage battery 21. The maximum charge/discharge power of the storage battery 21 is about 930 kW, since the power P2 varies between about +480 kW and about -930 kW. The battery capacity required by the storage battery 21 is about 270 kWh, since the charge/discharge power amount varies between about +0 kWh and about -270 kWh.

The maximum charge/discharge power of 400 kW of storage battery 11 is smaller than the maximum charge/discharge power of approximately 930 kW of storage battery 21. In addition, the battery capacity of approximately 270 kWh required by storage battery 21 is smaller than the battery capacity of approximately 1500 kWh required by storage battery 11. Therefore, the battery capacity (amount of charge/discharge power) of storage battery 21 can be suppressed while suppressing the output (maximum charge/discharge power) of storage battery 11. This effect will be further explained using a comparative example.

Figure 17 is a diagram showing a schematic configuration of a comparative example. The power supply system 100E according to the comparative example differs from the power supply system 100 (Figure 9) described so far in that it does not include a storage battery system 1. An "E" has been added to the reference numerals of some elements in the power supply system 100E. In the power supply system 100E, the rate of change of the power P3E at the connection point 3E is suppressed only by the power P2E of the storage battery 21E of the storage battery system 2E.

Figure 18 is a diagram showing an example of power P3E in a comparative example. The storage battery 21E is controlled to charge and discharge with power P2E, which suppresses the rate of change of power P3E.

Figure 19 is a diagram showing an example of the power P2E and the charge/discharge power amount of the storage battery 21E of the comparative example. The maximum charge/discharge power of the storage battery 21E is about 1270 kW because the power P2E varies between about +820 kW and about -1270 kW. The battery capacity required by the storage battery 21E is about 600 kWh because the charge/discharge power amount varies between about +0 kWh and about -600 kWh. The battery capacity of about 600 kWh required by the storage battery 21E of the comparative example is significantly larger than the battery capacity of about 270 kWh required by the storage battery 21 described above with reference to Figure 16.

18 and 19, the cause of the increase in the charge/discharge power amount (required battery capacity) of the storage battery 21E will be considered. For example, from time t1 to time t2, the time change of the power PG becomes considerably large, and a gradient state in which the difference between the power PG and the power P3E of the linkage point 3E increases continues. The continuation of the gradient state here means that the gradient difference (positive difference or negative difference) with the same sign continues. As a result of such a difference continuing, the state in which the power P2E is in the same direction (the charging direction in this example) continues, and the battery capacity required by the storage battery 21E becomes large. In the power supply system 100 according to the embodiment, the storage battery 11 bears the capacity for suppressing the gradient. The battery capacity required by the storage battery 21 is suppressed accordingly. Therefore, as described above, it is possible to suppress not only the output of the storage battery 11 but also the battery capacity of the storage battery 21.

<Temporary Stop of Storage Battery 11>
18 and 19 , even if the charging and discharging of the storage battery 11 is stopped when the gradient state does not continue for a long time, the effect of suppressing the battery capacity of the storage battery 21 can be obtained. Such a charging and discharging control may be performed by the charging and discharging control unit 43.

For example, if the first calculation unit 421 of the calculation unit 42 determines that a state in which the gradient state does not continue for a long time (non-gradient state) has continued for a certain period of time, it calculates the target value of the power P1 of the storage battery 11 as zero. A threshold judgment may be used to determine whether the non-gradient state continues. For example, if a state in which the rate of change of the power PG of the power generation device G is less than a threshold continues for a certain period of time, the first calculation unit 421 determines that the non-gradient state continues. For example, if the average gradient over 10 minutes is 10% or less, the charging and discharging of the storage battery 11 may be temporarily halted. The magnitude of the threshold and the length of the certain period may be set arbitrarily.

As a result of the first calculation unit 421 calculating the target value of power P1 as zero as described above, the charge/discharge control unit 43 controls the charge/discharge of the storage battery 11 so that the power P1 becomes zero. During this time, the charge/discharge of the storage battery 11 is temporarily stopped. In other words, the charge/discharge control unit 43 temporarily stops the charge/discharge of the storage battery 11 in response to the state in which the rate of change of the power P3 remains below the threshold for a certain period of time.

After the start of the stop, when a certain period of time (the length may be set arbitrarily) has passed or when the gradient state starts to continue again, the first calculation unit 421 calculates the target value of the power P1 so as to suppress the rate of change of the power P3, as before. The charge/discharge control unit 43 charges and discharges the storage battery 11. Specific examples will be described with reference to Figs. 20 to 25.

Figure 20 is a diagram showing an example of the target value of the power P1 of the storage battery 11. Time t3 is a time later than time t2 in Figure 18 described above. The non-gradient state continues for a certain period of time, and time t3 is reached. At time t3, the target value of the power P1 is calculated as zero. This calculation is repeated until time t4. At time t4, the target value of the power P1 is again calculated within the range of ±400 kW.

Figure 21 is a diagram showing an example of the total power (target value of PG+P1) of the power PG of the power generation device G and the target value of the power P1 of the storage battery 11. During the period when the target value of the power P1 is limited to the set value or calculated as zero, the rate of change is not yet sufficiently suppressed.

The second calculation unit 422 is the same as before. The second calculation unit 422 calculates a target value for power P2 so as to further suppress the rate of change of power P3 after it has been suppressed by power P1.

Figure 22 is a diagram showing an example of a target value of the power P2 of the storage battery 21. The target value of the power P2 of the storage battery 21 is calculated so as to further suppress the rate of change in the period in which the rate of change was not sufficiently suppressed in Figure 21 described above.

Figure 23 shows an example of power P3 at connection point 3. Power P1 and power P2 suppress the rate of change of power P3 at any time t.

Figure 24 is a diagram showing an example of the power P1 and the charge/discharge power amount of the storage battery 11. The maximum charge/discharge power of the storage battery 11 is 400 kW because the power P1 is limited within the range of ±400 kW. The battery capacity required by the storage battery 11 is approximately 530 kWh because the charge/discharge power amount varies between approximately +110 kWh and approximately -420 kWh.

Figure 25 is a diagram showing an example of the power P2 and the charge/discharge power amount of the storage battery 21. The maximum charge/discharge power of the storage battery 21 is 930 kW, since the power P2 varies between approximately +480 kW and approximately -930 kW. The battery capacity required by the storage battery 21 is approximately 330 kWh, since the charge/discharge power amount varies between approximately +0 kWh and approximately -330 kWh.

The battery capacity required by storage battery 21, approximately 330 kWh, is smaller than the battery capacity required by storage battery 11, approximately 530 kWh. In this way, even if the charging and discharging of storage battery 11 is temporarily suspended during a non-gradient state, the battery capacity of storage battery 21 can still be suppressed.

<Gradient cancellation using storage battery 11 as a long-period storage battery>
Returning to Fig. 9 again, the charging and discharging of storage battery 11, which is a large-capacity storage battery, may be used for smoothing over a relatively long period (long cycle), and the charging and discharging of storage battery 21, which is a high-output storage battery, may be used for smoothing over a relatively short period (short cycle). In this case, storage battery 11 can be said to be a long-cycle storage battery, and storage battery 21 can be said to be a short-cycle storage battery. Storage battery system 1 can be said to be a long-cycle storage battery system, and storage battery system 2 can be said to be a short-cycle storage battery system.

For example, the first calculation unit 421 calculates the target value of the power P1 based on the power PG of the power generation device G for each predetermined period. The predetermined period is a period longer than the unit period (such as one minute) of the rate of change described above, and is, for example, a period of several minutes, several tens of minutes, several tens of minutes, several hours, etc.

In one embodiment, the first calculation unit 421 may calculate the target value of the power P1 based on the averaged power PG of the power generation device G. The period for obtaining one average value corresponds to the predetermined period. The averaging method is not particularly limited, and for example, exponential averaging, interval averaging, moving average, etc. may be used. Exponential averaging requires less memory capacity than other averaging methods and is characterized by being easy to follow sudden changes. Interval averaging is characterized by being easy to show the trend when the same change continues for a long time and having a small data processing burden after averaging. The moving average is typically used when the same change continues for a long time. The first calculation unit 421 calculates the averaged power PG.

Figure 26 is a diagram showing an example of calculation of the target value of power P1 based on the averaged power PG. The first calculation unit 421 calculates the target value of power P1 calculated to suppress fluctuations in the averaged power PG as power P1c. Power P1c can also be considered a candidate value for the target value of power P1. The following describes an example where the set value is 400 kW.

The power P1c varies over a wide range from about 1140 kW to about -510 kW. As explained above, for example, when the set value is 400 kW, the first calculation unit 421 calculates the target value of the power P1 within the range of ±400 kW (within the set value range). When the magnitude of the power P1c exceeds 400 kW, the target value of the power P1 may be fixed to the set value. When the non-gradient state continues for a certain period of time, the target value of the power P1 may be calculated as zero. Other calculation methods are also possible. In the embodiment exemplified here, the first calculation unit 421 shifts the magnitude of the target value of the power P1 when the magnitude of the power P1c exceeds 400 kW. Specific explanations are given below.

In one embodiment, the first calculation unit 421 shifts the magnitude of the target value of the power P1 so that the magnitude of the target value of the power P1 does not exceed a set value while maintaining the target value of the power P1 to change over time in the same manner as the change over time of the power P1c. In this example, the change over time corresponds to the change over time of the averaged power PG. For example, the first calculation unit 421 shifts the magnitude of the power by providing an offset equivalent to the shift amount at the timing when the magnitude of the power exceeds 400 kW. If the magnitude of the power after the shift again exceeds 400 kW, the first calculation unit 421 provides a further offset at that timing. For example, the value of the power obtained in this manner is calculated as the target value of the power P1 of the storage battery 11.

In the example shown in FIG. 26, the magnitude of the target value of power P1 shifts to zero at each of times t11 to t15. Specifically, at times t14 and t15, the target value of power P1 shifts from near +400 kW to zero. For example, an offset of -400 kW is applied at each of these times. From time t11 to time t13, the target value of power P1 shifts from near -400 kW to zero. For example, an offset of +400 kW is applied at each of these times.

Figure 27 shows an example of the total power (target value of PG+P1) of the power PG of the power generation device G and the target value of the power P1 of the storage battery 11. Large fluctuations for each specified period have been smoothed out, but the rate of change for unit periods shorter than the specified period has not yet been suppressed.

Figure 28 is a diagram showing an example of a target value for the power P2 of the storage battery 21. The target value for the power P2 of the storage battery 21 is calculated so as to suppress the rate of change of the power P3.

The charge/discharge control unit 43 may control the charging and discharging of the storage battery 11 and the storage battery 21 based on the target value of power P1 and the target value of power P2 calculated as described above. For example, the charge/discharge control unit 43 controls the charging and discharging of the storage battery 11 based on the power PG for each predetermined period that is longer than the unit period of the rate of change of the power P3. The charge/discharge control unit 43 then controls the charging and discharging of the storage battery 21 based on the power PG for each unit period. In this case, the charge/discharge control unit 43 shifts the magnitude of the power P1 so that the magnitude does not exceed a set value while continuing the time change of the power P1 of the storage battery 11.

Figure 29 shows an example of power P3 at connection point 3. Power P1 and power P2 suppress the rate of change of power P3 at any time t.

Figure 30 is a diagram showing an example of the power P1 and the charge/discharge power amount of the storage battery 11. The maximum charge/discharge power of the storage battery 11 is 400 kW because the power P1 is limited within the range of ±400 kW. The battery capacity required by the storage battery 11 is approximately 800 kWh because the charge/discharge power amount varies between approximately +280 kWh and approximately -520 kWh.

Figure 31 is a diagram showing an example of the power P2 and the charge/discharge power amount of the storage battery 21. The maximum charge/discharge power of the storage battery 21 is about 1120 kW, since the power P2 varies between about +960 kW and about -1120 kW. The battery capacity required by the storage battery 21 is about 380 kWh, since the charge/discharge power amount varies between about +0 kWh and about -380 kWh.

Therefore, even if the storage battery 11 is used as a long-cycle storage battery or the magnitude of the power P1 is shifted within the range of the limit value, the battery capacity of the storage battery 21 can be suppressed while suppressing the output of the storage battery 11. Note that the battery capacity of the storage battery 21 is suppressed even by shifting the power P1 because the storage battery 11 is controlled to charge and discharge so as to continue the time change according to the time change of the power PG of the power generation device G, and thus bears the capacity for suppressing the gradient.

The above describes an example in which the magnitude of the power P1 of the storage battery 11 is shifted to zero. In addition to this, various other shifts are possible. For example, the magnitude of the power P1 may be shifted to a magnitude that reverses the charging and discharging of the storage battery 11. This point will also be described with reference to Figures 32 and 33.

32 and 33 are diagrams showing an example of a shift in the power P1 of the storage battery 11. Examples of set values include an upper limit power P1 _UL and a lower limit power P1 _LL . The upper limit power P1 _UL specifies the upper limit value of the power P1. The lower limit power P1 _LL specifies the lower limit value of the power P1.

32, the power P1 of the storage battery 11 changes over time to create a gradient from negative to positive. At the timing when the power P1c exceeds the upper limit power _P1UL , the power P1 shifts to the power _P1U . This makes it possible to suppress the amount of charge/discharge power required to change the power of the storage battery 21 from negative to positive.

33, the power P1 changes over time to create a gradient from positive to negative. At the timing when the power P1c falls below the lower limit power _P1LL , the power P1 shifts to the power _P1L . This makes it possible to suppress the charge/discharge capacity required to change the storage battery 21 from positive to negative.

What is important is the gradient, not the absolute value. If the values of P1 _LL and P1 _UL are in the charging direction, the amount of charging power of the storage battery 11 can be increased, and if the values of P1 _LL and P1 _UL are in the discharging direction, the amount of discharging power of the storage battery 11 can be increased. This also makes it possible to control and restrict the storage capacity of the storage battery 11.

The magnitudes (absolute values) of the upper limit power P1 _UL and the lower limit power P1 _LL may be the same or different. The shifted power P1 _U shown in FIG. 32 may be a value smaller than the upper limit power P1 _UL . The power P1 _U may be zero or less. When the power P1 _U is smaller than zero, the magnitude of the power P1 shifts to a magnitude at which the charging and discharging of the storage battery 11 is reversed. The shifted power P1 _L shown in FIG. 33 may be a value larger than the lower limit power P1 _LL . The power P1 _L may be zero or more. When the power P1 _L is greater than zero, the magnitude of the power P1 shifts to a magnitude at which the charging and discharging of the storage battery 11 is reversed.

<Second Application Example>
In the second application example, the charging and discharging of the storage battery 11 is controlled in a planned manner based on predictions.

Figure 34 is a diagram showing an example of the schematic configuration of a power supply system 100A in which a controller 4A according to the second application example is used. The controller 4A differs from the controller 4 (Figure 9) in that it includes an acquisition unit 41A, a calculation unit 42A, and a memory unit 44A instead of the acquisition unit 41, the calculation unit 42, and the memory unit 44, and further includes a plan unit 45.

In addition to the power information and battery information described above, the acquisition unit 41A also acquires information necessary for predicting the power PG of the power generation device G. An example of such information is meteorological information, such as information indicating wind power, solar radiation, and temperature for each time and time period. The meteorological information is acquired, for example, via an external network (not shown).

The planning unit 45 plans a target value for the power P2 of the storage battery 21. For example, the planning unit 45 predicts the future power PG of the power generation device G based on meteorological information acquired by the acquisition unit 41A described above. More specifically, the planning unit 45 calculates a predicted value of the power PG of the power generation device G for each future time and time period. Various known methods for predicting power generation may be used.

The planning unit 45 plans a target value of power P1 that suppresses fluctuations in the calculated predicted value of power PG of the power generating device G. For example, the planning unit 45 plans a target value of power P1 for each planning time period based on the predicted value of power PG for each planning time period. The planning time period may correspond to the predetermined period in the first embodiment described above. The length of each planning time period does not have to be the same. For example, the target value of power P1 for each planning time period of 15 minutes, 30 minutes, etc. is planned up to 24 hours ahead, 48 hours ahead, etc.

Figure 35 is a diagram showing an example of a plan for the target value of power P1 of the storage battery 11. Time t21 to time t22, time t22 to time t23, time t23 to time t24, time t24 to time t25, time t25 to time t26, time t26 to time t27, time t27 to time t28, and time t28 to time t29 each correspond to a planned time period. A target value for power P1 that suppresses fluctuations in power PG is planned based on the predicted value of power PG for each planned time period.

In this example, the target value of power P1 is planned to change with a constant slope over time or to have a constant magnitude for each planning time period. From time t23 to time t24 and from time t27 to time t28, the target value of power P1 is planned to change with a positive slope. From time t21 to time t22 and from time t25 to time t26, the target value of power P1 is planned to change with a negative slope. From time t22 to time t23, from time t24 to time t25, from time t26 to time t27, and from time t28 to time t29, the target value of power P1 is planned to have a constant magnitude.

The planning unit 45 shifts the magnitude of the target value of the power P1 while continuing the change over time so that the magnitude does not exceed the set value. The shifting method may be the same as that used by the first calculation unit 421 of the calculation unit 42 in the first embodiment described above. For example, from time t21 to time t22, the target value of the power P1 is shifted so as not to fall below -400 kW while continuing the negative slope. From time t23 to time t24, the target value of the power P1 is shifted so as not to exceed +400 kW while continuing the positive slope.

Of course, there may be planned time periods during which the target value of power P1 does not shift, such as from time t25 to time t26 and from time t27 to time t28. Also, the target value of power P1 is constant from time t22 to time t23, from time t24 to time t25, from time t26 to time t27, and from time t28 to time t29, so the target value of power P1 does not shift.

Returning to FIG. 34, calculation unit 42A differs from calculation unit 42 (FIG. 1) in that it includes a first calculation unit 421A instead of the first calculation unit 421. For example, first calculation unit 421A calculates the target value of power P1 planned by the planning unit 45 as the target value of power P1 as is. The first calculation unit 421A may not be necessary, in which case the planning unit 45 also performs the function of the first calculation unit 421A.

The second calculation unit 422 calculates a target value of the power P2 that suppresses the rate of change of the power P3 at the connection point 3. The charge/discharge control unit 43 controls the charge/discharge of the storage battery 11 and the storage battery 21 based on the calculation result of the calculation unit 42A. The details are the same as those of the first application example, so the description will not be repeated.

The memory unit 44A stores various information necessary for control by the controller 4A. An example of information stored in the memory unit 44A is the control program 441A. The control program 441A is a program that causes a computer to execute the control (processing) executed by the controller 4A. In addition, the memory unit 44A stores power information, battery information, weather information, etc. acquired by the acquisition unit 41A, and stores information necessary for planning by the planning unit 45 and calculation by the calculation unit 42.

In the power supply system 100A, the power P1 of the storage battery 11 continues to change over time, but is shifted so that its magnitude does not exceed a set value. This makes it possible to both suppress the output of the storage battery 11 and suppress the battery capacity of the storage battery 21.

In the power supply system 100A, it is only necessary to plan the target value of the power P1 to change with a certain gradient for each planning time period, or to plan it to have a certain magnitude. This has the effect of, for example, avoiding complex control. This effect can be obtained even if there is no shift in the power P1, and in this sense, a form in which the power P1 is not shifted can also be one form of the power supply system 100A.

In one embodiment, control may be performed taking into account the SOC of the storage battery. For example, the planning unit 45 may plan a target value for the power P1 of the storage battery 11 so that the SOC of the storage battery 21 at the end of the planned time period is close to the target SOC (target value of remaining capacity). This can also be said to be a plan to supply the power of the storage battery 21 with the storage battery 11. The end of the planned time period may be a few seconds, tens of seconds, or a few minutes before the end time of the planned time period. An example of the target SOC is about 50%. The possibility of maximizing the battery capacity of the storage battery 21 is increased. For example, a lithium-ion battery has a characteristic that deterioration progresses if it is left near full charge, so by increasing the frequency of charging and discharging near SOC 50%, the possibility of suppressing the progression of deterioration of the storage battery is increased.

The planning unit 45 may re-plan the target value of the power P2 for the next planning time period based on the actual SOC of the storage battery 21 at the end of the planning time period. This increases the likelihood that the SOC of the storage battery 21 at the end of the next planning time period will be close to the target SOC. Re-planning the target value of the power P2 for the next planning time period may include re-planning the target value of the power P1 for the next 24 hours, 48 hours, etc. from that time period.

In one embodiment, the charge and discharge of the storage battery 21 may be controlled so as to minimize the power P2 of the storage battery 21 within an acceptable range. For example, a charge and discharge control may be adopted in which the rate of change of the power P3, which is smaller than ±1%/min, is intentionally brought closer to +1%/min or -1%/min, thereby reducing the power P2 of the storage battery 21 accordingly. Since the magnitude of the power P2 is reduced, the battery capacity required by the storage battery 21 can be further reduced. Furthermore, by suppressing the charge and discharge of the storage battery 21, the progression of deterioration can be suppressed.

<Modification>
Some modified examples of the above-described embodiments will be described. In one embodiment, a load (demand) that consumes power may be included in the power supply system. This will be described with reference to FIG.

Figure 36 is a diagram showing an example of a load. A load that is connected to a power line W and consumes power from the power line W is referred to as load L and illustrated. Examples of the load L are a house, a factory, etc. The power consumed by the load L is referred to as power consumption PL and illustrated. Information on the power consumption PL is also transmitted from the load L to the controller and acquired, for example.

At least a portion of the power PG of the power generation device G is consumed by the load L. The remaining power (PG-PL) is power that can be supplied to the power grid 9 via the connection point 3. By treating this power in the same way as the power PG described above, the rate of change of the power P3 at the connection point 3 can be suppressed. To the extent that there is no contradiction, the power PG of the power generation device G may be interpreted as the power obtained by subtracting the power PL of the load L from the power PG of the power generation device G.

At least a portion of the power PG of the power generation device G is consumed by the load L. The remaining power (PG-PL) is power that can be supplied to the power grid 9 via the connection point 3. By treating this power in the same way as the power PG described above, the rate of change of the power P3 at the connection point 3 can be suppressed. To the extent that there is no contradiction, the power PG of the power generation device G may be interpreted as the power obtained by subtracting the power PL of the load L from the power PG of the power generation device G.

In the above embodiment, an example has been described in which the charging and discharging of each of the multiple storage battery systems 2 is controlled by the controller 4. However, multiple storage battery systems 1 may be present, in which case each of the multiple storage battery systems 1 may be controlled to charge and discharge by the controller 4, similar to the storage battery system 2.

In one embodiment, a trained model may be used to calculate the target values of power P1 and power P2. This will be described with reference to FIG. 37.

Figure 37 is a diagram showing an example of the schematic configuration of a controller 4B according to a modified example. Controller 4B differs from controller 4 (Figure 9) in that it includes a calculation unit 42B and a memory unit 44B instead of the calculation unit 42 and the memory unit 44, and in that it further includes a learning unit 46.

Examples of information stored in the memory unit 44B include a control program 441B, a learned model 442, and training data 443. The control program 441B is a program that causes a computer to execute control (processing) executed in the controller 4B. For example, when data (input data) corresponding to information acquired by the acquisition unit 41 is input, the learned model 442 outputs data (output data) corresponding to the target values of power P1 and power P2. The target values of power P1 and power P2 to which the output data corresponds are similar to the target values of power P1 and power P2 calculated by the calculation unit 42 (Figure 1) described above.

The learned model 442 is generated by training (machine learning, etc.) using training data 443 so as to output output data when input data is input. An example of the training data 443 is a data set that combines input data and output data. The data set may be prepared using data on past charge/discharge control of the storage batteries 11 and 21 performed in the power supply system, experimental data, simulation data, etc.

The calculation unit 42B calculates the target values of power P1 and power P2 using the trained model 442. The calculation unit 42B obtains the output data obtained by inputting the input data into the trained model 442 as the target values of power P1 and power P2.

Based on the target values of power P1 and power P2 calculated (acquired) by calculation unit 42B, charge/discharge control unit 43 controls the charging and discharging of storage battery 11 and storage battery 21.

The learning unit 46 learns the learned model 442 using the training data 443 stored in the memory unit 44B. This makes it possible to generate the learned model 442 and to update the learned model 442 based on the latest training data 443. Note that the learning unit 46 and the training data 443 may be provided outside the controller 4B (for example, an information processing device such as a server device not shown). In this case, the trained learned model 442 generated outside the controller 4B is provided to and used by the controller 4B.

Although not shown, the learned model may also be used for planning the target value of power P1 by the planning unit 45 of the controller 4A (FIG. 34). The learned model may also be used for calculating the target value of power p for each of the multiple storage battery systems 2.

In one embodiment, the function of the battery controller 14 of the storage battery system 1 may be incorporated into the controller 4. This allows for the configuration of the storage battery system 1 to be simplified, etc. The function of the battery controller 24 of the storage battery system 2 may be incorporated into the controller 4. This allows for the configuration of the storage battery system 2 to be simplified, etc.

In the application example described above, the controller 4 controls the charging and discharging of the storage battery system 1 and the storage battery system 2 based on the power PG (generated power) of the power generation device G so as to suppress the rate of change (rate of change in power value per unit period) of the power P3 (transferred and received power) at the connection point 3 between the power generation device G, the storage battery system 1 (first storage battery system) and the storage battery system 2 (second storage battery system) connected to the power generation device G, and the power grid 9. The storage battery 11 of the storage battery system 1 has a battery capacity larger than the battery capacity of the storage battery 21 of the storage battery system 2. The charging and discharging control includes charging and discharging the storage battery system 1 and the storage battery system 2 so that the maximum charging and discharging power of the storage battery system 1 is smaller than the maximum charging and discharging power of the storage battery system 2. The storage battery system 2 here is a plurality of storage battery systems 2, and as previously described with reference to Figures 1 to 7, each of them is controlled to be charged and discharged according to at least one operating purpose (including the first operating purpose).

In the controller 4, the two types of storage batteries, storage battery 11 and storage battery 21, are controlled to charge and discharge so as to suppress the rate of change of the power P3 at the connection point 3. The power generation device can be stabilized. In addition, charging and discharging are controlled. Storage battery 11 has a battery capacity larger than that of storage battery 21. Charging and discharging are controlled so that the maximum charging and discharging power of storage battery 11 is smaller than the maximum charging and discharging power of storage battery 21. The storage battery 11 used in this manner is a large-capacity storage battery. Storage battery 21 is a high-output storage battery. As described with reference to Figures 15 to 19, the battery capacity (charge and discharge power amount) of storage battery 21 can be suppressed more than when storage battery 11 is not used, while suppressing the output (maximum charging and discharging power) of storage battery 11. It is possible to achieve both suppression of the output of storage battery 11 (large-capacity storage battery) and suppression of the battery capacity of storage battery 21 (high-output storage battery).

In addition, the charging and discharging of the multiple storage battery systems 2 is controlled so that the operation efficiency E of each of the multiple storage battery systems 2 is increased. Therefore, it is possible to optimize the overall efficiency of the charging and discharging efficiency η _bat of the storage battery 21 and the power conversion efficiency η _pcs of the PCS 22 (power conversion device). In particular, by increasing the operation efficiency E of the storage battery system 2 including the storage battery 21, which is a high-output storage battery, the effect of suppressing the battery capacity of the storage battery 11 is further enhanced.

Reference Signs List 1 Battery storage system 2 Battery storage system 3 Coordination point 4 Controller 41 Acquisition unit 42 Calculation unit 43 Charge/discharge control unit 44 Memory unit 45 Planning unit 46 Learning unit 441 Control program 442 Learned model 443 Training data 444 System data G Power generation device P1 Power P2 Power p Power PG Power PL Power consumption

Claims (9)

A controller that controls charging and discharging of each of a plurality of storage battery systems according to an operation purpose,
Each of the plurality of storage battery systems includes a storage battery and a power conversion device connected to the storage battery,
the operation objectives include a first operation objective of charging and discharging each of the plurality of storage battery systems so as to increase the operating efficiency of each of the plurality of storage battery systems; a second operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a large remaining capacity with priority and charging, among the batteries of each of the plurality of storage battery systems, a battery having a small remaining capacity with priority; and a third operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a low price of electricity being charged with priority ;
the operating efficiency is an overall efficiency of the charging/discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to charging/discharging power,
The controller controls charging and discharging of each of the plurality of storage battery systems so that a determination value indicating a degree of overall reflection of the first operation objective, the second operation objective, and the third operation objective becomes large.
controller. The peak positions of the operation efficiencies of the plurality of storage battery systems are different from one another,
The first operating objective includes bringing the operating efficiency of each of the plurality of storage battery systems closer to a peak position.
The controller of claim 1 . The peak positions of the charge/discharge efficiency of each of the plurality of storage battery systems are different from each other.
The controller of claim 2 . The storage batteries of the plurality of storage battery systems are different from each other in at least one of design and period of use.
The controller of claim 3 . The determination value indicates an overall degree of each of the weighted driving purposes.
The controller of claim 1 . the controller controls charging and discharging of the first storage battery system and the second storage battery system so as to suppress a rate of change in power exchanged between the power generation device, the first storage battery system and the second storage battery system connected to the power generation device, and a power grid, based on power generated by the power generation device;
a storage battery of the first storage battery system has a battery capacity larger than a battery capacity of a storage battery of the second storage battery system;
the charge/discharge control includes charging/discharging the first storage battery system and the second storage battery system such that a maximum charge/discharge power of the first storage battery system is smaller than a maximum charge/discharge power of the second storage battery system;
The second storage battery system is the plurality of storage battery systems.
The controller according to any one of claims 1 to 4 . On the computer,
A control program for executing a process of controlling charging and discharging each of a plurality of storage battery systems according to an operation purpose,
Each of the plurality of storage battery systems includes a storage battery and a power conversion device connected to the storage battery,
the operation objectives include a first operation objective of charging and discharging each of the plurality of storage battery systems so as to increase the operating efficiency of each of the plurality of storage battery systems; a second operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a large remaining capacity with priority and charging, among the batteries of each of the plurality of storage battery systems, a battery having a small remaining capacity with priority; and a third operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a low price of electricity being charged with priority ;
the operating efficiency is an overall efficiency of the charging/discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to charging/discharging power,
controlling charging and discharging of each of the plurality of battery storage systems so that a determination value indicating a degree of overall reflection of the first operation objective, the second operation objective, and the third operation objective becomes large;
Control program. A control method for controlling charging and discharging of each of a plurality of storage battery systems according to an operation purpose, comprising:
Each of the plurality of storage battery systems includes a storage battery and a power conversion device connected to the storage battery,
the operation objectives include a first operation objective of charging and discharging each of the plurality of storage battery systems so as to increase the operating efficiency of each of the plurality of storage battery systems; a second operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a large remaining capacity with priority and charging, among the batteries of each of the plurality of storage battery systems, a battery having a small remaining capacity with priority; and a third operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a low price of electricity being charged with priority ;
the operating efficiency is an overall efficiency of the charging/discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to charging/discharging power,
controlling charging and discharging of each of the plurality of battery storage systems so that a determination value indicating a degree of overall reflection of the first operation objective, the second operation objective, and the third operation objective becomes large;
Control methods. A plurality of storage battery systems;
a controller that controls charging and discharging of each of the plurality of storage battery systems according to an operation purpose;
Equipped with
Each of the plurality of storage battery systems includes a storage battery and a power conversion device connected to the storage battery,
the operation objectives include a first operation objective of charging and discharging each of the plurality of storage battery systems so as to increase the operating efficiency of each of the plurality of storage battery systems; a second operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a large remaining capacity with priority and charging, among the batteries of each of the plurality of storage battery systems, a battery having a small remaining capacity with priority; and a third operation objective of discharging, among the batteries of each of the plurality of storage battery systems, a battery having a low price of electricity being charged with priority ;
the operating efficiency is an overall efficiency of the charging/discharging efficiency of the storage battery and the power conversion efficiency of the power conversion device with respect to charging/discharging power,
The controller controls charging and discharging of each of the plurality of storage battery systems so that a determination value indicating a degree of overall reflection of the first operation objective, the second operation objective, and the third operation objective becomes large.
Power supply system.

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