Charging control system, charging control method, and charging control program

Abstract

To reduce the possibility of supply shortages. [Solution] A charging control system is configured comprising: a charging remaining amount acquisition unit that acquires the current amount of power, which is the remaining charge, from multiple storage batteries; an estimated charging amount acquisition unit that acquires an estimated charging amount, which is the amount of power to be charged to the storage batteries by self-generation between the present and the start timing of discharge by the multiple storage batteries; an estimated remaining amount acquisition unit that acquires an estimated remaining amount, which is the amount of power of the storage batteries at the start timing, based on the remaining charge and the estimated charging amount; and a charging control unit that charges the storage batteries with an amount of power equivalent to the difference between the estimated remaining amount and a reference amount of power between the present and the start timing.

Description

Technical Field

[0003]

[0001] The present invention relates to a charging control system, a charging control method, and a charging control program.

Background Art

[0002] Conventionally, a technique for controlling the timing of charge and discharge in a storage battery has been known. For example, in Patent Document 1, a technique for creating a charge and discharge plan for a storage battery that maximizes the predicted value of trading profit is disclosed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, the market for power trading has diversified, and a capacity market is known as one of the markets. The capacity market is a market for trading future supply capacity (kW). An operator who bids and wins in the market needs to continuously supply power while maintaining a certain supply capacity for a certain period from the reference time when a start command is generated. An operator bidding in the capacity market secures supply capacity using various power sources. For this reason, it is assumed that an operator supplying power to the capacity market uses a storage battery used in a home or the like as a power source. That is, it is assumed that an operator bids on the premise of using a plurality of storage batteries, and controls the storage batteries in response to a start command to discharge to the power grid to secure a predetermined supply capacity.

[0005] Operators are required to maintain the supply capacity they specified during the bidding process for a certain period, and penalties will be imposed if the supply capacity falls short. Since the amount of electricity that can be supplied from the battery fluctuates depending on the amount of charge, operators must prepare so that the supply capacity does not fall short when an activation order is issued. This invention has been made in view of the above-mentioned problems, and aims to reduce the possibility of supply shortages. [Means for solving the problem]

[0006] To achieve the above objectives, the charging control system includes: a charging remaining amount acquisition unit that acquires the current amount of power, which is the remaining charge, from a plurality of storage batteries; an estimated charging amount acquisition unit that acquires an estimated charging amount, which is the amount of power to be charged to the storage batteries by self-generation between the present and the start timing of discharge by the plurality of storage batteries; an estimated remaining amount acquisition unit that acquires an estimated remaining amount, which is the amount of power in the storage batteries at the start timing, based on the remaining charge and the estimated charging amount; and a charging control unit that charges the storage batteries with an amount of power equivalent to the difference between the estimated remaining amount and a reference amount of power between the present and the start timing.

[0007] In other words, the charging control system controls the amount of power stored in the battery so that it reaches a reference amount between the present time and the start of discharge. Specifically, based on the increase in the amount of power generated by the battery through self-generation between the present time and the start of discharge, an estimated remaining amount of power, which is the amount of power in the battery at the start of discharge, is obtained. Then, the deficit to the reference amount of power is charged to the battery before the start of discharge. With this configuration, the probability of the battery reaching the reference amount at the start of discharge can be increased, and the possibility of insufficient power supply after the start of discharge can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This is a diagram of the charging control system. [Figure 2] This is a flowchart of the charging control process. [Figure 3] This figure shows the time-series change in the amount of electricity stored in a battery. [Modes for carrying out the invention]

[0009] Here, embodiments of the present invention will be described in the following order. (1) Configuration of the charging control system: (2) Charge control processing: (3) Instructions after discharge begins: (4) Other embodiments:

[0010] (1) Configuration of the charging control system: Figure 1 shows the configuration of the charging control system 10. In Figure 1, the exchange of signals and information is indicated by solid lines or solid arrows, and the exchange of power is indicated by dashed lines. The charging control system 10 is a computer used by an administrator to manage the discharge amount from multiple storage batteries. In this embodiment, the administrator is a business operator that bids in the capacity market. The capacity market is a market for trading future supply capacity (kW), and a business operator that bids in the market and wins the bid is required to continue supplying power to the power grid 70 while maintaining a certain supply capacity for a certain period from a reference point (3 hours after the activation command in this example) when an activation command is issued.

[0011] The power supply for supplying power to the power grid 70 in response to an activation command is prepared in advance by the operator. In this embodiment, the administrator of the charging control system 10 supplies at least a portion of the power supply with multiple storage batteries (first storage battery 51 to nth storage battery 5N). That is, when an activation command is issued, the administrator secures at least a portion of the bid-for supply capacity with storage batteries. In this embodiment, the multiple storage batteries are owned by their respective owners. The administrator has a contract with each owner, and each owner permits the storage batteries to be charged and discharged in response to instructions from the administrator. Of course, various payment terms may be set in the contract.

[0012] The charging control system 10 can communicate with the cloud server 60 via the internet. The cloud server 60 can communicate with N batteries (the first battery 51 to the nth battery 5N) (where N is an integer of 2 or more) and the weather information management server 80 via the internet.

[0013] The weather information management server 80 is a server that manages weather information for each region. It defines information indicating the weather for a predetermined period from the present onward for each region and stores it in a storage medium (not shown). In this embodiment, the weather information includes a weather forecast and a solar radiation forecast for a predetermined period from the present onward (for example, the next 3 hours). The weather forecast and solar radiation forecast only need to be information that allows the estimated charge amount of the storage battery to be obtained. In this embodiment, the weather forecast is a weather classification (sunny, cloudy, rainy, snowy, etc.), and the solar radiation forecast is the amount of radiant energy that a unit area of ​​an object on the Earth's surface receives from the sun per unit time.

[0014] The charging control system 10 can communicate with the first battery 51 to the nth battery 5N and the weather information management server 80 via the cloud server 60. The first battery 51 to the nth battery 5N are secondary batteries capable of charging and discharging electricity. The first battery 51 to the nth battery 5N are connected to the power grid 70 via a control device (not shown), and can receive power from the power grid 70 and also discharge power to supply power to the power grid 70. In this embodiment, the charging control system 10 can issue instructions to each of the first battery 51 to the nth battery 5N via the cloud server 60, causing the power grid 70 to charge each battery and the batteries to discharge power to the power grid 70. In this embodiment, each of the first battery 51 to the nth battery 5N belongs to a facility or house where a solar power generation device is installed, and it is also possible to charge each battery with electricity generated by the solar power generation device.

[0015] The charging control system 10 can acquire weather information via the cloud server 60. Specifically, the charging control system 10 specifies the region and time for which weather information should be acquired and requests the cloud server 60 to acquire the weather information. Upon receiving this request, the cloud server 60 communicates with the weather information management server 80, acquires the weather information for the specified region and time, and transmits it to the charging control system 10. The charging control system 10 then acquires the weather information transmitted from the cloud server 60.

[0016] The charging control system 10 includes a control unit 20 equipped with a CPU, RAM, ROM, etc., a storage medium 30, and a communication unit 40. The communication unit 40 is a device for communicating with the cloud server 60.

[0017] The storage medium 30 records various programs and various data. In this embodiment, the storage medium 30 stores battery information 30a. Battery information 30a is information related to the battery, and in this embodiment, it includes information indicating the remaining charge of the battery, specifications, charge history, and installation location.

[0018] Specifically, the battery information 30a includes the current remaining charge of the first battery 51 to the nth battery 5N. In this embodiment, the remaining charge is expressed in units of kWh, but the remaining charge can be defined in various ways. For example, it may be expressed as SOC (State of Charge), where 0% represents the state where the amount of charged energy is at its lower limit and 100% represents the state where the amount of charged energy is at its upper limit. In this case, the SOC is converted to the amount of charge, which is the amount of energy, based on information such as the power capacity of the batteries.

[0019] The specifications of the storage batteries include information indicating the power capacity of each of the first storage battery 51 to the Nth storage battery 5N. The power capacity is used to specify the amount of electric power when each storage battery is in a fully charged state. Further, the specifications of the storage batteries include information indicating the amount of electric power that can be charged per unit time by solar power generation in each of the first storage battery 51 to the Nth storage battery 5N, and information associated with a combination of a plurality of conditions. For example, the amount of electric power that can be charged per unit time is associated with a combination of the weather category and the value of the solar radiation amount, and is defined as table data. The amount of electric power that can be charged per unit time is used to estimate the amount of electric power charged in each storage battery.

[0020] The history of the remaining charge amount is information in which the remaining charge amounts of the first storage battery 51 to the Nth storage battery 5N are associated with time, and the history of the remaining charge amounts in time series is defined. The history of the remaining charge amount is used to predict the amount of self-consumption electric power in each storage battery. The installation location is information indicating the location where each of the first storage battery 51 to the Nth storage battery 5N is installed. The installation location is used to specify the weather information of the location.

[0021] The control unit 20 executes various programs stored in the storage medium 30 and the ROM. As an example of this program, the control unit 20 can execute a charge control program. When the charge control program is executed, the control unit 20 functions as a remaining charge amount acquisition unit 20a, an estimated charge amount acquisition unit 20b, an estimated remaining amount acquisition unit 20c, a charge control unit 20d, and a savings request unit 20e.

[0022] The remaining charge amount acquisition unit 20a is a function of acquiring the remaining charge amount, which is the current amount of electric power, from a plurality of storage batteries. That is, the control unit 20 transmits a request for acquiring the remaining charge amount to the cloud server 60 via the communication unit 40 by the function of the remaining charge amount acquisition unit 20a. The cloud server 60 communicates with the first storage battery 51 to the Nth storage battery 5N in response to the acquisition request, and acquires the current remaining charge amount of each storage battery.

[0023] The control unit 20 can acquire the current remaining charge at any time. In this embodiment, the control unit 20 can acquire the current remaining charge of each of the first battery 51 to the nth battery 5N during the process of processing in response to an activation command described later. The acquired current remaining charge is recorded in the storage medium as battery information 30a. In addition, the control unit 20 acquires the current remaining charge of each of the first battery 51 to the nth battery 5N at regular intervals in order to record the history of the remaining charge. The current time is associated with the acquired remaining charge and recorded in the storage medium as battery information 30a, forming the history of the remaining charge.

[0024] The estimated charge amount acquisition unit 20b has the function of acquiring the estimated charge amount, which is the amount of electricity that will be charged to the batteries by self-generation from the present until the start timing of discharge by the multiple batteries. In this embodiment, the start timing of discharge is 3 hours after the activation command. In this embodiment, the self-generation is solar power generation that can charge each of the first batteries 51 to the Nth batteries 5N with the generated electricity. Therefore, the control unit 20 estimates the amount of charge by self-generation based on the weather forecast, solar radiation forecast, and self-power consumption forecast from the present until the start timing, using the function of the estimated charge amount acquisition unit 20b.

[0025] Specifically, the control unit 20 outputs a request to the cloud server 60 to acquire weather information for each location where the first battery 51 to the nth battery 5N are located, and acquires the weather information returned from the cloud server 60. The control unit 20 refers to the table data contained in the battery information 30a and acquires the amount of energy that can be charged per unit time corresponding to the combination of weather category and solar radiation value for each location contained in the weather information. Then, the control unit 20 determines the amount of energy that will be charged by solar power generation from the present to the start of discharge by multiplying the time length from the present to the start of discharge by the amount of energy that can be charged per unit time.

[0026] Furthermore, the control unit 20 predicts the amount of self-consumption power based on the history of remaining charge. In this embodiment, the control unit 20 identifies the amount of self-consumption power for the period from the present to the start of discharge by extrapolating to the history of remaining charge. The control unit 20 then obtains the estimated charge amount by subtracting the amount of self-consumption power from the amount of electricity charged by solar power generation during the period from the present to the start of discharge.

[0027] The estimated remaining charge acquisition unit 20c has the function of acquiring the estimated remaining charge, which is the amount of power in the battery at the start timing, based on the remaining charge and the estimated charge amount. In other words, the control unit 20 considers the sum of the remaining charge and the estimated charge amount to be the estimated remaining charge, based on the function of the estimated remaining charge acquisition unit 20c.

[0028] The charging control unit 20d has the function of charging the battery with an amount of energy equivalent to the difference between the estimated remaining energy and the reference energy amount between the present and the start timing. In this embodiment, the reference energy amount is the energy amount when fully charged. The control unit 20, using the function of the charging control unit 20d, identifies the difference between the energy amount when fully charged and the estimated remaining energy for each of the first battery 51 to the Nth battery 5N. The control unit 20 then outputs an instruction to the cloud server 60 via the communication unit 40 to charge each of the first battery 51 to the Nth battery 5N with power from the power system 70. In response to this instruction, the cloud server 60 instructs each of the first battery 51 to the Nth battery 5N to charge with power from the power system 70. As a result, each of the first battery 51 to the Nth battery 5N is charged with the instructed amount of energy by the start timing.

[0029] With the above configuration, the probability that all of the first battery 51 to the nth battery 5N will be fully charged at the time of discharge in response to the activation command can be increased. Therefore, compared to the case where the first battery 51 to the nth battery 5N are not fully charged, the possibility of insufficient power supply after the start of discharge can be reduced. The administrator needs to maintain a certain power supply for a certain period from the start of discharge, and in order to maintain the power supply, power sources other than the first battery 51 to the nth battery 5N, such as batteries or power plants owned by the administrator, may be used in conjunction.

[0030] Furthermore, in this embodiment, the amount of charge generated by self-generation is estimated based on the weather forecast, solar radiation forecast, and self-consumption power forecast from the present to the start time. Therefore, the amount of charge can be estimated more accurately compared to when the amount of charge generated by self-generation is estimated without referring to this information.

[0031] With the above configuration, discharge occurs from each battery after the discharge start timing. After the discharge starts, measures may be taken to further increase the likelihood that the administrator can continue to supply power to the power grid 70 while maintaining a constant supply capacity. In this embodiment, the control unit 20 increases the likelihood that the administrator can maintain a constant supply capacity by requesting the battery owner (including the user) to reduce their self-consumption of electricity through the function of the energy conservation request unit 20e.

[0032] Specifically, the energy-saving request unit 20e has the function of requesting multiple battery owners to conserve their self-consumption of electricity after the start timing. That is, when discharge begins, the control unit 20 outputs an execution instruction for the energy-saving request to the cloud server 60 via the communication unit 40. In response to this execution instruction, the cloud server 60 outputs an execution instruction for the energy-saving request to terminals (not shown) used by each battery owner (e.g., mobile terminals, home power control terminals, etc.). As a result, the energy-saving request is displayed on the display unit of each terminal. If each battery owner reduces their self-consumption of electricity in response to the energy-saving request, an amount of electricity that can be discharged from the battery to the power grid 70 will be secured, and the possibility of a power shortage after the start timing of discharge can be reduced.

[0033] (2) Charge control processing: Next, the charging control process will be described in detail. Figure 2 is a flowchart of the charging control process. In this embodiment, the control unit 20, using the function of the remaining charge acquisition unit 20a, sends a request to the cloud server 60 via the communication unit 40 to acquire the remaining charge at regular intervals (every 30 minutes in this embodiment) in parallel with the charging control process. When such an acquisition request is made, the cloud server 60 transmits the current remaining charge of the first battery 51 to the nth battery 5N. The control unit 20 acquires this information via the communication unit 40 and adds it to the history of remaining charge included in the battery information 30a.

[0034] In the charging control process, the control unit 20 monitors whether an activation command has been generated (step S100) and waits until it is determined that an activation command has been generated. The generation of an activation command may be notified to the charging control system 10 by any method, and in this embodiment, it is assumed that the generation of an activation command is notified to the charging control system 10 via the Internet. When an activation command is generated, the control unit 20 identifies the time the activation command was generated based on a timing circuit (not shown) and stores it in a storage medium such as RAM.

[0035] In step S100, when it is determined that an activation command has been issued, the control unit 20, using the function of the charge control unit 20d, determines whether the current time is the start of discharge (step S105). The start of discharge is 3 hours after the activation command has been issued. The control unit 20 identifies the current time based on a timing circuit (not shown) and, in the loop processing process from step S105 onward, determines whether the current time is the start of discharge.

[0036] In this embodiment, the control unit 20 individually performs the acquisition of the remaining charge amount by the function of the remaining charge acquisition unit 20a, the acquisition of the estimated charge amount by the function of the estimated charge amount acquisition unit 20b, the acquisition of the estimated remaining charge by the function of the estimated remaining charge acquisition unit 20c, and the control of charging by the function of the charge control unit 20d for each of the multiple storage batteries. For this reason, if it is not determined in step S105 that the current time is the start of discharge, the control unit 20 selects a storage battery to be processed (step S115). That is, in the loop processing of steps S115 to S150, the control unit 20 selects one of the first storage battery 51 to the nth storage battery 5N as the target of processing. For this reason, the control unit 20 selects one storage battery that has not been targeted for processing in steps S115 to S150 as the target of processing, and performs the processing of steps S115 to S150 on the selected storage battery.

[0037] Next, the control unit 20 acquires the remaining charge using the function of the remaining charge acquisition unit 20a (step S120). That is, the control unit 20 sends a request to the cloud server 60 via the communication unit 40 to acquire the remaining charge of the battery that was processed in step S115. The cloud server 60 communicates with the requested battery, acquires the current remaining charge of the battery, and sends it to the charging control system 10. The charging control system 10 records the acquired remaining charge as battery information 30a on the storage medium.

[0038] Figure 3 shows the time-series change in the energy content of a certain battery, with the horizontal axis representing time and the vertical axis representing the energy content of the battery [kWh]. In Figure 3, the energy content of the battery is shown by a solid line. The remaining charge obtained in step S120 is the remaining charge at the time the activation command was issued, which is P0 in Figure 3.

[0039] Next, the control unit 20 determines whether the battery to be processed is fully charged or not, based on the function of the charge level acquisition unit 20a (step S125). Specifically, the control unit 20 refers to the battery information 30a, acquires the power capacity of the battery to be processed, and identifies the amount of power stored when fully charged. Then, if the charge level acquired in step S120 matches the amount of power stored when fully charged (including cases where the difference is less than or equal to a threshold), the control unit 20 determines that the battery to be processed is fully charged.

[0040] If, in step S125, it is determined that the battery to be processed is fully charged, then charging the battery to be processed is unnecessary, and the control unit 20 skips the processing in steps S130 to S145.

[0041] On the other hand, if it is determined in step S125 that the battery to be processed is not fully charged, the control unit 20 uses the function of the estimated charge amount acquisition unit 20b to acquire the weather forecast, solar radiation forecast, and self-consumption amount forecast (step S130). Specifically, the control unit 20 refers to the battery information 30a and identifies the installation location of the battery to be processed. The control unit 20 also outputs a request to the cloud server 60 to acquire the weather forecast and solar radiation forecast along with the installation location of the battery to be processed. When such an acquisition request is made, the cloud server 60 acquires the weather forecast and solar radiation forecast requested from the weather information management server 80 and outputs them to the charging control system 10. The charging control system 10 acquires the weather forecast and solar radiation forecast via the communication unit 40.

[0042] Furthermore, the control unit 20 predicts the amount of self-consumption power based on the history of the remaining charge. To this end, the control unit 20 refers to the battery information 30a and obtains the history of the remaining charge within a predetermined period prior to the present. The predetermined period can be any period of a predetermined length for the purpose of extrapolation interpolation. The control unit 20 then identifies the amount of self-consumption power for the period from the present to the start of discharge by extrapolating to the history of the remaining charge within the predetermined period. In Figure 3, the dashed line L1 shows the change in the amount of energy due to self-consumption during the period from the present to the start of discharge, which was obtained by extrapolation. The control unit 20 obtains the difference P01 between the amount of energy P1 when the dashed line L1 reaches the start of discharge and the remaining charge P0 at the time the activation command is issued as the predicted value of the self-consumption power.

[0043] Next, the control unit 20 acquires the estimated charge amount using the function of the estimated charge amount acquisition unit 20b (step S135). Specifically, the control unit 20 acquires the estimated charge amount by subtracting the amount of self-consumed power from the amount of power charged by solar power generation during the period from the present to the start of discharge. To perform this calculation, the control unit 20 refers to the table data contained in the battery information 30a and acquires the amount of power that can be charged per unit time in the battery to be processed, based on the combination of weather classification and solar radiation values ​​for each location contained in the weather information. Then, the control unit 20 determines the amount of power that will be charged by solar power generation from the present to the start of discharge by multiplying the time length from the present to the start of discharge by the amount of power that can be charged per unit time. In the example shown in Figure 3, the amount of power that will be charged by solar power generation from the present to the start of discharge is the power amount P02.

[0044] Once the amount of electricity to be charged by solar power generation from the present until the start of discharge is obtained, the control unit 20 estimates the charge amount by subtracting the amount of self-consumed electricity from the amount of electricity to be charged by solar power generation from the present until the start of discharge. In the example shown in Figure 3, the control unit 20 calculates P02-P01 to obtain the estimated charge amount P03.

[0045] Next, the control unit 20 acquires the estimated remaining charge, which is the amount of energy in the battery being processed at the start of discharge, using the function of the estimated remaining charge acquisition unit 20c (step S140). Specifically, the control unit 20 acquires the remaining charge plus the estimated charge amount as the estimated remaining charge. In the example shown in Figure 3, the remaining charge P0 + estimated charge amount P03 becomes the estimated remaining charge P3.

[0046] Next, the control unit 20 controls the battery to be processed so that it charges an amount of energy obtained by (amount of energy when fully charged - estimated remaining amount) / number of remaining unit periods in a unit period, according to the function of the charge control unit 20d (step S145). Specifically, in this embodiment, the control unit 20 updates the target value of the charge control for each unit period. Here, a unit period is a period obtained by dividing the period from the activation command to the start timing of discharge into multiple periods, and the length of this period is predetermined. In this embodiment, the unit period is 30 minutes. Therefore, there are 6 unit periods within the 3 hours period from the activation command to the start timing of discharge.

[0047] Furthermore, the control unit 20 uses the amount of energy obtained by dividing the difference value (amount of energy when fully charged - estimated remaining amount) by the number of remaining unit periods at the time of processing as the control target and instructs the battery to be processed to charge. In other words, the control unit 20 specifies the battery to be processed and the amount of energy via the communication unit 40 and outputs a charging instruction to the cloud server 60. As a result, the cloud server 60 instructs the specified battery to charge the specified amount of energy from the power system 70. As a result, the specified battery starts charging the specified amount of energy.

[0048] In the example shown in Figure 3, there are six unit periods T from the activation command to the start of discharge, and the processing from steps S105 to S150 is executed at the start of each unit period T. Therefore, at the start of each unit period T, the amount of energy at full charge minus the estimated remaining amount is determined, and the amount of energy obtained by dividing it by the number of remaining unit periods T becomes the control target.

[0049] For example, at the timing when the activation command is issued, the number of remaining unit periods T is 6. Therefore, the control unit 20 sets (full charge energy Pmax - estimated remaining energy P3) / 6 as the control target and controls the battery to be processed so that it is charged during unit periods T. Also, for example, at timing T1, the number of remaining unit periods T is 4, so the control unit 20 sets (full charge energy Pmax - estimated remaining energy obtained at timing T1) / 4 as the control target and controls the battery to be processed so that it is charged during unit periods T.

[0050] Thus, by using a configuration that re-identifies the control target for each unit period T, the amount of power, which is the control target, becomes more accurate. For example, in the estimation performed at the time the activation command is issued, it is estimated that the amount of power generated by solar power generation and the amount of self-consumption per unit time remain constant from the time the activation command is issued onward. From this estimation, the estimated remaining amount at timing T1 becomes Ps. However, if the estimated remaining amount of the battery is obtained again at timing T1, the estimated remaining amount may differ from Ps. That is, if the processing of steps S115 to S150 is executed at timing T1, the control unit 20 obtains the estimated remaining amount based on the remaining charge at timing T1, the weather forecast, the solar radiation forecast, the self-consumption forecast, and the estimated charge amount, and determines the control target for charging based on this estimated remaining amount. For this reason, the control target at the time the activation command is issued and the control target at timing T1 may differ. Furthermore, by using a configuration that updates the control target for charging for each unit period T, the estimation becomes more accurate, and the possibility of achieving full charge at the start of discharge can be increased.

[0051] Next, the control unit 20 determines whether processing has been completed for all batteries using the function of the charge control unit 20d (step S150). That is, the control unit 20 determines whether all of the first batteries 51 to the nth batteries 5N have been processed. If it is not determined in step S150 that processing has been completed for all batteries, the control unit 20 repeats the processing from step S115 onwards.

[0052] If it is determined in step S150 that processing has been completed for all batteries, the control unit 20 determines whether or not a unit period T has elapsed, based on the function of the charge control unit 20d (step S155). That is, the control unit 20 identifies the current time based on the output of a timing circuit (not shown), and determines that a unit period T has elapsed if the current time is an integer multiple of the time the activation command was issued plus the unit period T.

[0053] In step S155, if it is not determined that the unit period T has elapsed, the control unit 20 repeats the determination in step S155 at regular intervals. In step S155, if it is determined that the unit period T has elapsed, the control unit 20 repeats the processing from step S105 onward. Then, in step S105, if it is determined that it is now the timing to start discharging, the control unit 20 starts discharging each battery using the function of the charge control unit 20d (step S110). That is, the control unit 20 sends a discharge start request to the cloud server 60 via the communication unit 40. When the cloud server 60 receives the discharge start request, the cloud server 60 starts discharging each battery. As a result, the likelihood of the administrator being able to continue supplying power to the power grid 70 while maintaining a constant supply capacity increases.

[0054] (3) Instructions after discharge begins: When discharge begins, the control unit 20, using the function of the energy-saving request unit 20e, requests energy saving from each battery owner. Specifically, the energy-saving request unit 20e outputs an execution command for the energy-saving request to the cloud server 60 via the communication unit 40. In response to this execution command, the cloud server 60 causes each battery owner to output the energy-saving request to a terminal (not shown) used by that battery owner (e.g., a mobile terminal, a household power control terminal, etc.).

[0055] In Figure 3, the amount of energy remaining in the battery after the start of discharge is also shown by a solid line. In Figure 3, it is assumed that between the start and end of discharge, energy P04 was discharged to the power grid 70 based on the administrator's instructions, and energy P05 was consumed by the battery owner for self-consumption. As a result, at the end of discharge, the amount of energy remaining in the battery is energy P4.

[0056] In this example, it is assumed that a request for energy conservation was made, and the battery owner complied with the request by reducing self-consumption. If self-consumption had not been reduced, self-consumption would have increased, and the amount of power in the battery might have decreased further, as shown by the dashed line L2. In this way, if the amount of power in the battery decreases further and the battery becomes uncharged before the end of discharge, the administrator would need to maintain a certain level of supply using other power sources, such as a power plant owned by the administrator, which would make it difficult to maintain supply capacity. However, according to this embodiment, the possibility of insufficient battery power can be reduced by the request for energy conservation.

[0057] Furthermore, the system may be configured such that if the battery owner reduces their self-consumption of electricity after the start time below a predetermined power level in response to a power-saving request, the compensation paid to the owner will be greater than if they did not reduce their consumption. That is, when the administrator charges the battery in response to an activation command and starts discharging to the power grid 70 at the start of discharge timing, the administrator pays compensation to the battery owner. Therefore, the system may be configured such that if the owner reduces their self-consumption of electricity below a predetermined power level in response to a power-saving request, the compensation paid to the owner will be greater than if they did not reduce their consumption. This configuration can increase the number of owners who respond to power-saving requests and reduce the possibility of a shortage of battery power. The predetermined power level may be an indicator used to determine whether or not to increase the compensation, for example, the battery owner's normal self-consumption of electricity (power consumption per unit time). Of course, whether or not to increase the compensation may also be evaluated based on whether or not the amount of self-consumption of electricity, which is the integral of self-consumption of electricity over a predetermined period, is less than a predetermined amount of electricity. Furthermore, the system may be configured so that the compensation increases as the amount of electricity or energy consumed is reduced.

[0058] (4) Other embodiments: The above embodiments are merely examples for carrying out the present invention, and various other embodiments can be adopted. For example, the charging control system may be implemented by multiple devices, or it may be implemented using a cloud server or the like. Furthermore, the charging control system 10 may be able to communicate with N batteries, a weather information management server 80, terminals used by battery owners, etc., without going through the cloud server 60.

[0059] Furthermore, at least a portion of the charge level acquisition unit 20a, estimated charge level acquisition unit 20b, estimated remaining charge acquisition unit 20c, charge control unit 20d, and energy saving request unit 20e may be divided into multiple devices. Of course, some of the configurations of the above-described embodiment may be omitted, and the order of processing may be changed or omitted. For example, the processing shown in Figure 2 may not be executed every unit period T, but may be executed once when an activation command is issued, and charge control may be performed during the period from the activation command to the start of discharge. Also, the processing may be repeated for longer or shorter periods. Furthermore, the storage battery is not limited to a battery that charges with electricity generated by a solar power generation device. For example, it may be a storage battery mounted on a vehicle. Also, the self-generation is not limited to solar power generation, but may be wind power generation, small hydropower generation, biomass power generation, geothermal power generation, etc.

[0060] The charge level acquisition unit only needs to be able to acquire the current amount of power, or charge level, from multiple batteries. The charge level is the current amount of power stored in the batteries and may be determined based on various information. In other words, in addition to a configuration in which a value indicating the charge level is acquired from the batteries, the charge level may also be acquired from information indicating the State of Charge (SOC) and the specifications of the batteries (power capacity, etc.), or the amount of dischargeable capacity that can be discharged from the batteries may be acquired as the charge level.

[0061] The estimated charge acquisition unit only needs to be able to acquire the estimated charge amount, which is the amount of electricity that will be charged to the batteries by self-generation between the present time and the start of discharge by multiple batteries. In other words, the estimated charge acquisition unit only needs to be able to acquire the amount of electricity that should not be included in the amount of electricity charged by the charge control unit. In the case of a capacity market, the start of discharge is a time after a certain period has elapsed since the activation command, but if multiple batteries start discharging simultaneously at a predetermined time, the charge control system may also be applied to electricity trading in markets other than the capacity market.

[0062] The estimated charge amount can be obtained using various methods. For example, the estimated charge amount may be obtained based on one or two of the following: weather forecasts from the present to the start time, solar radiation forecasts, and self-consumption power consumption forecasts. Alternatively, the estimated charge amount may be obtained based on other information, such as season, latitude and longitude. If the self-consumption power generation is not solar power generation, the estimated charge amount may be obtained based on other factors, such as wind power, rainfall forecasts, etc.

[0063] The charging control unit only needs to be able to charge the battery with an amount of energy equivalent to the difference between the estimated remaining energy and the reference energy amount between the present and the start timing. In other words, the charging control unit only needs to be able to control the amount of energy stored in the battery so that the battery reaches the reference energy amount at the start timing. The reference energy amount can be any value that indicates the amount of charge that should be secured at the start timing, and is typically the energy amount of a full charge, but may also be other values, such as the energy amount of a full charge minus a predetermined margin.

[0064] Furthermore, the charging control unit may be configured to charge more electricity to the battery now than it will charge later, if the current electricity purchase price is lower than the standard price. For example, in the control for each unit period T shown in Figure 3, if the electricity purchase price is lower than the standard price (e.g., the average value) in a given unit period T, the amount of electricity charged in that unit period T is increased compared to the amount of electricity charged in subsequent unit periods T. This configuration increases the likelihood of reducing the total cost of electricity purchased to charge the battery compared to the case where the amount of electricity is not adjusted according to the price.

[0065] Furthermore, embodiments of the invention may also be programs or methods. Moreover, such systems, programs, and methods can be implemented as a single device or through multiple devices, encompassing various forms. They can also be modified as appropriate, such as being partly software and partly hardware. Furthermore, the invention also functions as a recording medium for a program that controls the system. Of course, the recording medium for the software may be a magnetic recording medium, a semiconductor memory, or any recording medium developed in the future; the same principle applies. [Explanation of Symbols]

[0066] 10...Charging control system, 20...Control unit, 20a...Charging remaining amount acquisition unit, 20b...Estimated charging amount acquisition unit, 20c...Estimated remaining amount acquisition unit, 20d...Charging control unit, 20e...Energy saving request unit, 30...Storage medium, 30a...Battery information, 40...Communication unit, 51~5N...1st battery~Nth battery, 60...Cloud server, 70...Power grid, 80...Weather information management server

Claims

1. A charge level acquisition unit that acquires the current amount of charge remaining from multiple storage batteries, An estimated charge amount acquisition unit acquires an estimated charge amount, which is the amount of electricity to be charged into the batteries by self-generation between the present time and the start timing of discharge by the multiple batteries, An estimated remaining charge acquisition unit acquires the estimated remaining charge, which is the amount of power in the battery at the start timing, based on the remaining charge and the estimated charge; A charge control unit that charges the battery with an amount of energy equivalent to the difference between the estimated remaining amount and the reference amount of energy between the present and the start timing, A charging control system equipped with this feature.

2. The aforementioned private power generation is solar power generation, The estimated charge amount acquisition unit, The estimated charge amount is obtained based on at least one of the weather forecast, solar radiation forecast, and self-consumption forecast from the present until the aforementioned start time. The charging control system according to claim 1.

3. The charging control unit divides the time from the present to the start timing into multiple periods, and charges the battery with the amount of power obtained by dividing the amount of power corresponding to the difference by the number of periods during the periods from the present onward. A charging control system according to claim 1 or claim 2.

4. The charging control unit, when the current electricity purchase price is lower than the standard price, sets the amount of electricity to be charged to the battery now to be greater than the amount of electricity to be charged later. A charging control system according to claim 1 or claim 2.

5. The acquisition of the remaining charge by the remaining charge acquisition unit, the acquisition of the estimated charge amount by the estimated charge amount acquisition unit, the acquisition of the estimated remaining charge by the estimated remaining charge acquisition unit, and the control of charging by the charge control unit are performed individually for each of the multiple storage batteries. A charging control system according to claim 1 or claim 2.

6. The system further includes a conservation request unit that requests multiple owners of the aforementioned storage batteries to conserve their self-consumption of electricity after the start timing, A charging control system according to claim 1 or claim 2.

7. If the owner reduces their self-consumption of electricity after the start time to below a predetermined level in response to the aforementioned request for energy conservation, the compensation paid to the owner will be greater than if they did not reduce their consumption. The charging control system according to claim 6.

8. A charge level acquisition step that obtains the current amount of charge remaining from multiple batteries, The estimated charge amount acquisition step acquires an estimated charge amount, which is the amount of electricity to be charged into the batteries by self-generation between the present time and the start timing of discharge by the multiple batteries, An estimated remaining charge acquisition step, which acquires the estimated remaining charge, which is the amount of power in the battery at the start timing, based on the remaining charge and the estimated charge; A charging control step that causes the battery to be charged with an amount of energy equivalent to the difference between the estimated remaining amount and the reference amount of energy between the present and the start timing, A charging control method including the following.

9. Computers, A charge level acquisition unit that acquires the current amount of charge remaining from multiple storage batteries. An estimated charge amount acquisition unit acquires an estimated charge amount, which is the amount of electricity to be charged into the batteries by self-generation between the present time and the start timing of discharge by the multiple batteries. An estimated remaining charge acquisition unit acquires the estimated remaining charge, which is the amount of power in the battery at the start timing, based on the remaining charge and the estimated charge. A charge control unit that charges the battery with an amount of energy equivalent to the difference between the estimated remaining amount and the reference amount between the present and the start timing. A charging control program that functions as such.

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