Energy storage control device and energy storage system

Abstract

In a configuration that controls the charging and discharging of a battery using energy storage plan data, the present invention provides a configuration that can suppress rapid charging and discharging that occurs in the battery. [Solution] The energy storage control device includes an energy storage control unit 10 having an energy storage planning unit 14 that generates energy storage planning data, which is data relating to the planning of energy storage of the battery 3, based on the predicted power generation value, the predicted power demand value, and the amount of energy stored in the battery 3 that charges and discharges power, and a charge and discharge command generation unit 15 that generates charge and discharge command values ​​based on the previous energy storage planning data, and a charge and discharge control unit that controls the charging and discharging of the battery 3 based on the energy storage planning data. The charge and discharge command generation unit 15 corrects the charge and discharge command value based on the error when an error occurs between the charge and discharge command value generated based on the energy storage planning data and the battery status value.

Description

Technical Field

[0001] The present invention relates to a power storage control device and a power storage system for controlling the power storage amount of a battery.

Background Art

[0002] A power storage control device and a power storage system for controlling the power storage amount of a battery are known. As an example of such a power storage control device, for example, in Patent Document 1, for each power generation system having a renewable energy power source and a storage battery charged only from the renewable energy power source, based on the predicted power generation value of the renewable energy power source and the power selling unit price, a management device is disclosed that includes a planning unit for creating a charge / discharge plan for the storage battery that maximizes the predicted value of the power selling profit and a power generation plan for the power generation system.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when creating a charge / discharge plan for a storage battery as disclosed in the above Patent Document 1, appropriate charge / discharge control of the battery as the storage battery is required. If appropriate charge / discharge control of the battery is not performed, there is a possibility of generating power that cannot be stored in the battery, or when the power demand increases, using the power of the grid power in addition to the power supplied from the battery and exceeding the contract power. Therefore, by predicting the power generation amount and the power demand amount as in Patent Document 1 and creating a power storage plan as the charge / discharge plan of the battery, the occurrence of the above situations is prevented.

[0005] However, when generating electricity using renewable energy sources, the amount of electricity generated can fluctuate significantly depending on weather conditions. Furthermore, if electricity demand increases more than predicted, the amount of stored energy may fall below the planned capacity. Thus, there is a possibility of errors in the energy storage plan. This could lead to rapid charging and discharging of the batteries.

[0006] In response to this, there is a need for a configuration that can suppress rapid charging and discharging of the battery in a system that uses energy storage plan data to control the charging and discharging of the battery.

[0007] The object of the present invention is to provide a configuration that can suppress rapid charging and discharging of a battery in a configuration that controls the charging and discharging of a battery using energy storage plan data. [Means for solving the problem]

[0008] A battery storage control device according to one embodiment of the present invention includes a battery storage planning unit that generates battery storage planning data, which is data relating to the planning of battery storage, based on a predicted power generation value, a predicted power demand value, and the amount of charge stored in a battery that charges and discharges power; a battery storage control unit that generates a charge and discharge command value based on the battery storage planning data; and a charge and discharge control unit that controls the charging and discharging of the battery based on the battery storage planning data. The charge and discharge command generation unit corrects the charge and discharge command value based on the error when an error occurs between the charge and discharge command value generated based on the battery storage planning data and the battery status value (first configuration).

[0009] As a result, the charge / discharge command generation unit can correct the charge / discharge command value input to the charge / discharge control unit so that the actual amount of charge in the battery matches the charge / discharge command value if there is an error between the charge / discharge command value generated based on the energy storage plan data and the actual amount of charge in the battery. Therefore, the actual amount of charge in the battery can be brought closer to the charge / discharge command value in the energy storage plan more quickly. Consequently, the charging and discharging of the battery can be controlled to match the energy storage plan data, and rapid charging and discharging of the battery can be suppressed. This can prevent exceeding the contracted power limit by using grid power, and prevent the battery from being damaged and degraded.

[0010] Furthermore, rapid charging and discharging of the battery refers to charging and discharging that repeatedly damages the battery and causes it to deteriorate.

[0011] In the first configuration described above, the charge / discharge command generation unit corrects the charge / discharge command value so that the actual amount of charge stored in the battery is less than the upper limit of the charge depth and greater than the lower limit of the charge depth if an error greater than or equal to a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of charge stored in the battery, and the actual amount of charge stored in the battery is greater than or equal to the upper limit of the charge depth or less than or equal to the lower limit of the charge depth (second configuration).

[0012] As a result, if an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in the battery, and the amount of charge stored in the battery is above the upper limit of the charge depth or below the lower limit of the charge depth, the charge / discharge command value can be corrected to quickly bring the actual amount of charge to a value that is less than the upper limit of the charge depth and greater than the lower limit of the charge depth. Therefore, rapid charging and discharging in the battery can be suppressed, and the deterioration of the battery can be suppressed.

[0013] In the first configuration described above, if an error exceeding a predetermined amount occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery, the charge / discharge command generation unit corrects the charge / discharge command value so that the actual amount of energy stored in the battery matches the energy storage plan data at the next plan update timing and changes gradually within the period until the next plan update timing (third configuration).

[0014] This allows the battery's charging and discharging to be controlled so that, even if a predetermined error occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery, the actual amount of energy stored in the battery matches the energy storage plan data at the next plan update timing. Therefore, the charge / discharge command value can be set without waiting for the next plan update timing, and the error can be quickly reduced. Consequently, it is possible to prevent the error from accumulating and causing the actual amount of energy stored in the battery to deviate significantly from the energy storage plan data.

[0015] Furthermore, by gradually changing the charge / discharge command value within the period until the next plan update timing, it is possible to prevent large fluctuations in the actual amount of charge stored in the battery. Therefore, it is possible to suppress rapid charging and discharging that occurs in the battery.

[0016] In the first configuration described above, if an error exceeding a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery, the energy storage plan unit generates new energy storage plan data that changes the charge / discharge command value so that the actual amount of energy stored in the battery matches the energy storage plan data at the next plan update timing (fourth configuration).

[0017] As a result, if the error between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery exceeds a certain value, instead of abruptly correcting the charge / discharge command value to match the actual amount of energy stored in the battery, new energy storage plan data can be generated that has been corrected to match the energy storage plan data at the next plan update timing. Therefore, it is possible to prevent the actual amount of energy stored from increasing or decreasing significantly in response to the charge / discharge command value based on the energy storage plan data. Thus, the battery can be charged and discharged efficiently, and it is possible to more reliably prevent the battery from being subjected to a heavy load and degrading.

[0018] An energy storage system according to one embodiment of the present invention comprises a rechargeable battery, a power generation unit that outputs generated electricity to the battery, and an energy storage control device having one of the first to fourth configurations (fifth configuration).

[0019] As a result, using the energy storage control device having the first to fourth configurations described above, it is possible to realize an energy storage system that suppresses the effects of errors and controls the charging and discharging of the battery even when an error occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery. Therefore, it is possible to realize an energy storage system that can suppress rapid charging and discharging that occurs in the battery. [Effects of the Invention]

[0020] A battery storage control device according to one embodiment of the present invention includes a battery storage planning unit that generates battery storage planning data, which is data relating to the planning of battery storage, based on a predicted value of power generation, a predicted value of power demand, and the amount of charge stored in a battery that charges and discharges power; a battery storage control unit that generates a charge and discharge command value based on the battery storage planning data; and a charge and discharge control unit that controls the charging and discharging of the battery based on the battery storage planning data. The charge and discharge command generation unit corrects the charge and discharge command value based on the error when an error occurs between the charge and discharge command value generated based on the battery storage planning data and the amount of charge stored in the battery.

[0021] As a result, in a configuration in which charging and discharging of the battery is controlled using the power storage plan data, a configuration capable of suppressing rapid charging and discharging occurring in the battery can be realized.

Brief Description of the Drawings

[0022] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a power storage system having a power storage control device according to Embodiment 1 in functional blocks. [Figure 2] FIG. 2 is a diagram showing a schematic configuration of a power storage control unit in functional blocks. [Figure 3] FIG. 3 is a diagram showing a schematic configuration of a power storage plan unit in functional blocks. [Figure 4] FIG. 4(a) is an explanatory diagram showing an example of a time-series change in the battery charge / discharge amount in the situation of FIG. 4(b), and FIG. 4(b) is an explanatory diagram showing an example of the relationship between the planned update timing and the charge / discharge command value in the time-series change of the battery storage amount. [Figure 5] FIG. 5(a) is an explanatory diagram showing an example of a time-series change in the battery charge / discharge amount in the situation of FIG. 5(b), and FIG. 5(b) is an explanatory diagram showing an example of a time-series change in the battery storage amount when controlling the charging and discharging of the battery based on a corrected charge / discharge command value before the next planned update timing. [Figure 6] FIG. 6(a) is an explanatory diagram showing an example of a time-series change in the battery charge / discharge amount in the situation of FIG. 6(b), and FIG. 6(b) is an explanatory diagram showing another example of a time-series change in the battery storage amount when controlling the charging and discharging of the battery based on a corrected charge / discharge command value before the next planned update timing. [Figure 7] FIG. 7 is a diagram showing a schematic configuration of a power storage control unit of a power storage control device according to Embodiment 2 in functional blocks. [Figure 8] FIG. 8(a) is an explanatory diagram showing an example of a time-series change in the battery charge / discharge amount in the situation of FIG. 8(b), and FIG. 8(b) is an explanatory diagram showing an example of a time-series change in the battery storage amount when controlling the charging and discharging of the battery based on a charge / discharge command value generated from newly generated corrected power storage plan data. [Figure 9]Figure 9(a) is an explanatory diagram showing an example of the time-series change in battery charge and discharge amounts in the situation shown in Figure 9(b), and Figure 9(b) is an explanatory diagram showing another example of the time-series change in battery charge amount when battery charge and discharge are controlled based on charge and discharge command values ​​generated from newly generated corrected energy storage plan data. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described in detail below with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and their descriptions will not be repeated.

[0024] [Embodiment 1] (Energy storage system) Figure 1 is a diagram showing the schematic configuration of a power storage system 100 having a power storage control device 1 according to Embodiment 1 of the present invention, in functional blocks. This power storage system 100 supplies power generated by the power generation unit 2 to the grid power, and in response to surplus power or power shortages that occur during the operation of the power storage system 100, it supplies power from the battery 3 to the grid power or stores power in the battery 3. The power supplied to the grid power is consumed by the power consumption unit 50.

[0025] Specifically, the energy storage system 100 includes an energy storage control device 1, a power generation unit 2, a battery 3, and DC / AC converters 4 and 5. The energy storage control device 1 controls the operation of the DC / AC converter 4 and controls the charging and discharging of the battery 3. The detailed configuration of the energy storage control device 1 will be described later.

[0026] The power generation unit 2 is a device that generates electricity using renewable energy sources such as solar power. The electricity generated by the power generation unit 2 is supplied to the grid power supply via the DC / AC converter 5. The power generation unit 2 may also be configured to generate electricity using energy sources other than renewable energy.

[0027] Battery 3 is configured to be rechargeable and dischargeable for DC power. The power from battery 3 is supplied to the grid power via the DC / AC converter 4, or the power from the grid power is stored in it. Battery 3 may also be supplied with power from sources other than the grid power (for example, the power generation unit 2).

[0028] The DC / AC converter 4 converts the direct current power output from the battery 3 into alternating current power and supplies it to the grid. The DC / AC converter 4 controls the power output from the battery 3 based on the charge / discharge commands output from the energy storage control device 1, which will be described later.

[0029] (Energy storage control device) Next, the configuration of the energy storage control device 1 will be described. The energy storage control device 1 generates energy storage plan data and controls the charging and discharging of the battery 3 based on the energy storage plan data. The energy storage plan data is data for planning the amount of energy stored in the battery 3, and includes, for example, data for the time-series change of the amount of energy stored.

[0030] The energy storage control device 1 comprises an energy storage control unit 10 and a charge / discharge control unit 30. The energy storage control unit 10 generates the energy storage plan data based on the power generation amount prediction by the power generation unit 2 and the power demand prediction by the power consumption unit 50, etc., and outputs it to the charge / discharge command generation unit 15, which will be described later. The energy storage control unit 10 also generates a charge / discharge command value (corresponding to an energy storage amount command value that charges and discharges the battery 3 so that the battery storage amount reaches a predetermined value) based on the energy storage plan data, and outputs it to the charge / discharge control unit 30.

[0031] Figure 2 is a diagram showing the schematic configuration of the energy storage control unit 10 in terms of functional blocks. As shown in Figure 2, the energy storage control unit 10 includes a power generation measurement data storage unit 11, a demand measurement data storage unit 12, a battery charge / discharge data storage unit 13, an energy storage planning unit 14, and a charge / discharge command generation unit 15.

[0032] The power generation measurement data storage unit 11 stores the measured data of the amount of electricity generated by the power generation unit 2. The demand measurement data storage unit 12 stores the measured data of electricity demand by the power consumption unit 50, etc. The battery charge / discharge data storage unit 13 stores the measured data of the charge and discharge of the battery 3.

[0033] The energy storage planning unit 14 generates energy storage planning data for battery 3. Specifically, the energy storage planning unit 14 generates the energy storage planning data based on actual power generation data stored in the actual power generation data storage unit 11, actual power demand data stored in the actual demand data storage unit 12, actual charge and discharge data of battery 3 stored in the battery charge and discharge data storage unit 13, power generation impact data that is affected by power generation by the power generation unit 2, past power demand performance data, and other data (such as actual grid power data such as grid power values, equipment information, and power constraint information). The energy storage planning unit 14 is implemented by a computing device such as a computer. The energy storage planning unit 14 may generate the energy storage planning data by machine learning, for example. The power generation impact data is, for example, data related to weather when the power generation unit 2 generates power using renewable energy (for example, solar power generation), and is data that predicts the weather based on past weather data. The past power demand performance data is, for example, data based on data consumed in the past by the power consumption unit 50, etc.

[0034] Figure 3 is a diagram showing the schematic configuration of the energy storage planning unit 14 in terms of functional blocks. As shown in Figure 3, the energy storage planning unit 14 includes a power generation forecasting unit 21, a power generation forecasting error calculation unit 22, a power demand forecasting unit 23, a power demand forecasting error calculation unit 24, a battery charge rate calculation unit 25, and an energy storage plan generation unit 26.

[0035] The power generation forecasting unit 21 uses the power generation impact data to predict power generation and obtain a predicted power generation value. The power generation forecast error calculation unit 22 calculates the error between the power generation value based on the actual power generation measurement data and the predicted power generation value obtained by the power generation forecasting unit 21, and outputs this as a power generation forecast error to the power generation forecasting unit 21. The power generation forecasting unit 21 outputs the power generation forecast value, which takes the power generation forecast error into consideration, as the final forecast value to the energy storage plan generation unit 26.

[0036] The power demand forecasting unit 23 uses the historical power demand data to forecast power demand and obtain a predicted power demand value. The power demand forecast error calculation unit 24 calculates the error between the power demand value based on the actual power demand data and the power demand forecast value from the power demand forecasting unit 23, and outputs this as a demand forecast error to the power demand forecasting unit 23. The power demand forecasting unit 23 outputs the power demand forecast value, which takes the demand forecast error into account, as the final forecast value to the energy storage plan generation unit 26.

[0037] The battery charge rate calculation unit 25 calculates the battery charge rate, which is an example of the amount of charge stored in the battery 3, based on the battery charge / discharge prediction data. In this embodiment, the battery charge rate calculation unit 25 calculates the battery charge rate, but any indicator related to the amount of charge stored in the battery 3, such as the depth of discharge (DOD), may also be calculated. The battery charge rate means the ratio of the amount of charge to the battery capacity, and the depth of charge (State of Charge) of the battery 3 means the ratio of the amount of discharge to the battery capacity. The upper and lower limits of the depth of charge are set in advance within a range of depth of charge that does not accelerate the deterioration of the battery 3. The battery charge rate calculation unit 25 outputs the calculated charge rate of the battery 3 to the energy storage plan generation unit 26. The battery charge rate calculation unit 25 also outputs the calculated charge rate of the battery 3 to the charge / discharge command generation unit 15.

[0038] The energy storage plan generation unit 26 generates energy storage plan data using the predicted power generation value output from the power generation forecasting unit 21, the predicted power demand value output from the power demand forecasting unit 23, the charge rate of the battery 3 output from the battery charge rate calculation unit 25, and other data. The other data includes, for example, the power values ​​of the grid power mentioned above, equipment information constituting the energy storage system 100, and power constraint information.

[0039] In the aforementioned energy storage plan data, the planned amount of charge stored in battery 3 is determined at regular intervals based on the update timing of data such as weather information. Therefore, in the charge / discharge control unit 30's charge / discharge control of battery 3, the target value for charge / discharge control (charge / discharge command value) is determined based on the energy storage plan data at the aforementioned plan update timing, and charge / discharge control of battery 3 is performed. In this embodiment, the battery's charge rate, which makes it easy to understand the battery's state (remaining battery charge), is used to understand the amount of charge stored in battery 3. However, any index that can define the amount of charge stored in battery 3, such as the depth of discharge, may be used.

[0040] The charge / discharge command generation unit 15 calculates the error between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3 (the charge rate of the battery 3). If the error does not exceed a predetermined value, it generates a charge / discharge command value and outputs it to the charge / discharge control unit 30. The charge / discharge control unit 30 generates a charge / discharge command based on the charge / discharge command value and controls the charging and discharging of the battery 3 by controlling the drive of the DC / AC converter 4 with this charge / discharge command.

[0041] On the other hand, if the charge / discharge command generation unit 15 detects an error greater than a predetermined value between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3, it corrects the charge / discharge command value output to the charge / discharge control unit 30 so that the actual amount of energy stored in the battery 3 matches the charge / discharge command value based on the energy storage plan data at the next plan update timing, thereby gradually changing the actual amount of energy stored in the battery 3 within the period until the next plan update timing. In other words, if the charge / discharge command generation unit 15 detects an error greater than a predetermined value between the charge / discharge command value and the actual amount of energy stored in the battery 3, it corrects the charge / discharge command value to generate a corrected charge / discharge command value and outputs it to the charge / discharge control unit 30. The charge / discharge control unit 30 generates a charge / discharge command based on the corrected charge / discharge command value and controls the charging and discharging of the battery 3.

[0042] In this embodiment, the charge / discharge command generation unit 15 selectively generates and outputs a charge / discharge command value and a corrected charge / discharge command value according to the error between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3. However, for example, the generation unit that generates and outputs the charge / discharge command value and the correction generation unit that generates and outputs the corrected charge / discharge command value may be configured separately. Also, in this embodiment, the charge / discharge command value is corrected so that the actual amount of energy stored in the battery 3 matches the charge / discharge command value based on the energy storage plan data at the next plan update timing. However, the charge / discharge command value may be corrected to approach the charge / discharge command value based on the energy storage plan data at the next plan update timing.

[0043] Figure 4(b) shows an example of the time-series change in battery charge when the energy storage plan data (black squares in Figure 4(b)) is updated at the energy storage plan data update timings T1 and T2 (hereinafter referred to as plan update timings T1 and T2), and charging and discharging are performed using the new charge / discharge command values ​​(solid lines in Figure 4(b)) generated at those timings.

[0044] As shown in Figure 4(b), for example, if the prediction errors of the power generation prediction unit 21 or the power demand prediction unit 23 are larger than expected, an error greater than a predetermined value may occur between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3. In this case, the error between the charge / discharge command value and the actual amount of energy stored in the battery 3 may become greater than a predetermined value by the time of the next plan update timing T2. In this case, as shown in Figure 4(a), the battery 3 will rapidly charge and discharge in order to follow the charge / discharge command value, which can lead to damage or deterioration of the battery 3. Furthermore, if the error between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3 is large at the time of the next plan update timing T2, the battery 3 may rapidly charge and discharge at this time as well, potentially affecting the charge / discharge control based on the next energy storage plan data.

[0045] On the other hand, Figure 5(b) is a diagram showing an example of the time-series change in the battery charge amount when, similar to Figure 4(b), the energy storage plan data is updated at the plan update timings T1 and T2, but an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in battery 3, and the charge / discharge command value is corrected between the plan update timings T1 and T2 for charging and discharging.

[0046] In Figure 5(b), a corrected charge / discharge command value (indicated by a white circle in Figure 5(b)) is set to gradually change the amount of charge stored in battery 3 over a shorter period than the plan update timing, based on a correction reference value (a straight line graph in Figure 5(b)) that connects the energy storage plan data at plan update timing T1 and the energy storage plan data at plan update timing T2, during the period from plan update timing T1 to the next plan update timing T2. This allows the charge / discharge control unit 30 to control the amount of charge stored in battery 3 based on the corrected charge / discharge command value without waiting until the next plan update timing T2.

[0047] Therefore, as shown in Figure 5(b), even if an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in battery 3, the accumulation of the error between the charge / discharge command value and the actual amount of charge stored in battery 3 can be suppressed, and the actual amount of charge stored in battery 3 can be quickly brought closer to the amount of charge stored in battery 3 using the energy storage plan data. As a result, the amount of charge stored in battery 3 can easily follow the energy storage plan data, and rapid charging and discharging of battery 3 can be suppressed. Moreover, even if rapid charging and discharging occurs in battery 3, damage and deterioration of battery 3 can be suppressed. Furthermore, at the next plan update timing T2, the impact on charge / discharge control based on the next energy storage plan data is reduced.

[0048] Furthermore, the error between the charge / discharge command value and the actual amount of charge stored in battery 3 being greater than or equal to a predetermined value may, for example, be when the actual amount of charge stored in battery 3 has an error that makes it certain that it will deviate from the charge / discharge command value and the amount of charge plan data at the next plan update timing T2 (for example, when the rate of change of the charge rate of battery 3 exceeds a predetermined value within a period shorter than the update timing of each amount of charge plan data, such as the period when setting the corrected charge / discharge command value), or it may be when the actual amount of charge stored in battery 3 is less than or equal to the lower limit of the charge depth or greater than or equal to the upper limit of the charge depth.

[0049] As shown in Figure 5(b), the charge / discharge command generation unit 15 generates a corrected charge / discharge command value that is greater than the lower limit of the charging depth and smaller than the charge / discharge command value, and that gradually changes so that the charge / discharge command value matches the energy storage plan data at the next plan update timing T2. The charge / discharge control unit 30 generates a charge / discharge command based on the corrected charge / discharge command value. This suppresses large fluctuations in the actual amount of energy stored in the battery 3.

[0050] In this embodiment, the corrected charge / discharge command value is set based on a correction reference value represented by a linear graph, as shown in Figure 5(b). However, the correction reference value may be represented by a curved graph (for example, a quadratic curve). By setting the corrected charge / discharge command value based on such a correction reference value, it is possible to suppress large fluctuations in the actual amount of charge stored in the battery 3, especially when an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in the battery 3 immediately after the plan update timing T1.

[0051] Furthermore, in this embodiment, the corrected charge / discharge command value is set at the timing when the error between the actual amount of charge stored in the battery 3 and the energy storage plan data exceeds a predetermined value, within the period from the plan update timing T1 to the next plan update timing T2, as indicated by the white circle in Figure 5(b). However, the corrected charge / discharge command value may also be set so that the amount of charge stored in the battery 3 changes gradually over a shorter period than the plan update timing, within the period from the plan update timing T1 to the next plan update timing T2, as indicated by the white circle in Figure 6(b). In this case, for example, if an error exceeding a predetermined value occurs between the charge / discharge command value and the actual amount of charge stored in the battery 3 before the plan update timing T1, the corrected charge / discharge command value within the period from the plan update timing T1 to the next plan update timing T2 can be set in advance, as shown in Figure 6(b), to suppress the accumulation of errors between the charge / discharge command value and the actual amount of charge stored in the battery 3 from the time of the plan update timing T1, and the actual amount of charge stored in the battery 3 can be brought closer to the energy storage plan data more quickly. Therefore, rapid charging and discharging of battery 3 can be further suppressed, and damage and degradation of battery 3 can be further suppressed.

[0052] Furthermore, if a predetermined error occurs between the charge / discharge command value and the actual amount of charge stored in the battery 3, and the actual amount of charge falls below the lower limit of the charging depth, the charge / discharge command generation unit 15 may, prioritizing that the amount of charge stored in the battery 3 be greater than the lower limit of the charging depth, temporarily generate a corrected charge / discharge command value without relying on a correction reference value, as shown by the hatched circle in Figure 6(b). This allows the actual amount of charge stored in the battery 3 to be quickly increased to be greater than the lower limit of the charging depth, even if the actual amount of charge stored in the battery 3 falls below the lower limit of the charging depth. This helps to suppress damage and degradation of the battery 3.

[0053] The charge / discharge command generation unit 15 may set the corrected charge / discharge command value to any value as long as the charge level of the battery 3 is greater than the lower limit of the charge depth, less than the upper limit of the charge depth, and close to the charge / discharge command value.

[0054] The charge / discharge command generation unit 15, in conjunction with the control described above, changes the lower limit of the battery depth of 3. This allows the battery 3 to be used effectively by controlling the charging and discharging of the battery 3 using a range lower than the lower limit of its charge depth. Furthermore, when rapid charging and discharging occur, changing the lower limit of the battery depth of 3 expands the range of the battery's stored energy, preventing the maximum demand power (demand value) from being updated even when using power exceeding the contracted power. In addition, if the amount of energy stored in the battery 3 exceeds the original lower limit of its charge depth after the charge / discharge command generation unit 15 has changed the lower limit of its charge depth, it returns it to the original lower limit of its charge depth, thereby minimizing the period during which the actual amount of energy stored in the battery 3 is below the lower limit of its charge depth. This reduces damage and degradation of the battery 3 compared to when the lower limit of its charge depth is not returned to its original value.

[0055] In this embodiment, the energy storage control device 1 includes an energy storage control unit 10 having an energy storage planning unit 14 that generates energy storage planning data, which is data relating to the planning of energy storage in the battery 3, based on the predicted power generation value, the predicted power demand value, and the amount of energy stored in the battery 3 that charges and discharges power, and a charge and discharge command generation unit 15 that generates charge and discharge command values ​​based on the energy storage planning data, and a charge and discharge control unit 30 that controls the charging and discharging of the battery 3 based on the charge and discharge command values. The charge and discharge command generation unit 15 corrects the charge and discharge command values ​​based on the error when an error occurs between the charge and discharge command values ​​generated based on the energy storage planning data and the battery status values.

[0056] As a result, the charge / discharge command generation unit 15 can correct the charge / discharge command value input to the charge / discharge control unit 30 to match the actual charge amount of the battery 3 if there is an error between the charge / discharge command value generated based on the energy storage plan data and the actual amount of energy stored in the battery 3. Therefore, the actual amount of energy stored in the battery 3 can be brought closer to the charge / discharge command value in the energy storage plan more quickly. Consequently, the charging and discharging of the battery 3 can be controlled to match the energy storage plan, and rapid charging and discharging of the battery 3 can be suppressed. This prevents exceeding the contracted power limit by using grid power, and prevents the battery 3 from being damaged and degraded.

[0057] Furthermore, in this embodiment, if a predetermined error occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3, and the actual amount of energy stored is less than or equal to the lower limit of the charging depth, the charge / discharge command value is corrected so that the actual amount of energy stored is greater than the lower limit of the charging depth.

[0058] As a result, if an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in the battery 3, and the actual amount of charge stored in the battery 3 is below the lower limit of the charge depth, the charge / discharge command value can be corrected to quickly set the actual amount of charge to a value that is less than the upper limit of the charge depth and greater than the lower limit of the charge depth. Therefore, rapid charging and discharging in the battery 3 can be suppressed, and the deterioration of the battery 3 can be suppressed.

[0059] Furthermore, in this embodiment, if an error exceeding a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery, the charge / discharge command generation unit 15 corrects the charge / discharge command value so that the actual amount of energy stored in the battery matches the energy storage plan data at the next plan update timing and changes gradually within the period until the next plan update timing.

[0060] This allows the charging and discharging of battery 3 to be controlled so that the actual amount of charge stored in battery 3 matches the energy storage plan data at the next plan update timing T2, even if there is an error greater than a predetermined value between the charge / discharge command value based on the energy storage plan data and the actual amount of charge stored in battery 3. Therefore, the charge / discharge command value can be set without waiting for the next plan update timing T2, and the error can be quickly reduced. Consequently, it is possible to prevent the actual amount of charge stored in battery 3 from accumulating and deviating significantly from the energy storage plan data.

[0061] Furthermore, by gradually changing the charge / discharge command value within the period until the next plan update timing T2, it is possible to prevent large fluctuations in the actual amount of charge stored in the battery 3. Therefore, rapid charging and discharging of the battery 3 can be suppressed.

[0062] [Embodiment 2] Figure 7 is a diagram showing the schematic configuration of the energy storage control unit 110 of the energy storage control device according to Embodiment 2, using functional blocks. The functions of the energy storage planning unit 114 and the charge / discharge command generation unit 115 in the energy storage control unit 110 of this embodiment differ from those of the energy storage control unit 10 of Embodiment 1. In the following, components similar to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted, and only components that differ from Embodiment 1 will be described.

[0063] The energy storage control unit 110 includes a power generation measurement data storage unit 11, a demand measurement data storage unit 12, a battery charge / discharge data storage unit 13, an energy storage planning unit 114, and a charge / discharge command generation unit 115.

[0064] The energy storage planning unit 114 calculates the error between the charge / discharge command value based on the energy storage planning data and the actual amount of energy stored in the battery 3 (the charge rate of the battery 3 calculated by the battery charge rate calculation unit 25). If the error does not exceed a predetermined value, it outputs the energy storage planning data to the charge / discharge command generation unit 115.

[0065] If the energy storage planning unit 114 detects an error greater than a predetermined value between the charge / discharge command value based on the energy storage planning data and the actual amount of energy stored in the battery 3, it generates new energy storage planning data that changes the charge / discharge command value so that the actual amount of energy stored in the battery 3 matches the energy storage planning data at the next planning update timing T2, and outputs this data to the charge / discharge command generation unit 115.

[0066] The charge / discharge command generation unit 115 generates charge / discharge command values ​​based on energy storage plan data and outputs them to the charge / discharge control unit 30, similar to the charge / discharge command generation unit 15. However, in this embodiment, if there is no error greater than a predetermined amount between the charge / discharge command value and the actual amount of energy stored in the battery 3, the charge / discharge command generation unit 115 selects the energy storage plan data and generates charge / discharge command values ​​based on this data and outputs them to the charge / discharge control unit 30. On the other hand, if there is an error greater than a predetermined amount between the charge / discharge command value and the actual amount of energy stored in the battery 3, the charge / discharge command generation unit 115 selects new energy storage plan data and generates charge / discharge command values ​​based on this energy storage plan data and outputs them to the charge / discharge control unit 30. The charge / discharge control unit 30 generates charge / discharge commands based on the charge / discharge command values ​​and controls the charging and discharging of the battery 3.

[0067] As described above, when generating new energy storage plan data, the energy storage plan unit 114 or the charge / discharge command generation unit 115 must have a function to detect when an error exceeding a predetermined amount occurs between the charge / discharge command value and the actual amount of energy stored in the battery 3.

[0068] If the energy storage planning unit 114 has the above function, the charge / discharge command value is fed back from the charge / discharge command generation unit 115 to the energy storage planning unit 114, and the energy storage planning unit 114 detects that an error of a predetermined amount or more has occurred between the actual amount of energy stored in the battery 3 (value calculated by the battery charge rate calculation unit 25) and the calculated value, and generates new energy storage planning data.

[0069] Furthermore, similar to the charge / discharge command generation unit 15, if the charge / discharge command generation unit 115 has the above function, an error detection signal (a signal related to detecting that an error exceeding a predetermined level has occurred) is input from the charge / discharge command generation unit 115 to the energy storage planning unit 114, and the energy storage planning unit 114 generates new energy storage planning data based on the error detection signal.

[0070] Figure 8(b) is a diagram showing an example of the time-series change in the amount of charge stored in battery 3 when, similar to Figure 5(b), the energy storage plan data is updated at the plan update timings T1 and T2, but an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in battery 3, and the charge / discharge command value is corrected between the plan update timings T1 and T2 for charging and discharging.

[0071] In Figure 8(b), if the error between the charge / discharge command value based on the energy storage plan data and the actual amount of charge stored in battery 3 exceeds a predetermined value, the energy storage plan unit 114 generates new energy storage plan data (corrected energy storage plan data) (black triangle in Figure 8(b)) to set a corrected charge / discharge command value that matches the energy storage plan data for the next plan update timing T2 and changes gradually over a shorter period than the plan update timing, during the period from the plan update timing T1 to the next plan update timing T2. The charge / discharge command generation unit 115 generates a charge / discharge command value based on the corrected energy storage plan data and outputs it to the charge / discharge control unit 30.

[0072] The energy storage planning unit 114 generates corrected energy storage planning data such that the charge / discharge command value gradually increases toward the planning update timing T2 from a value based on the timing when the error exceeds a predetermined value (for example, a setting value greater than the minimum charge amount of battery 3 after the timing when the error exceeds a predetermined value, as shown by the leftmost black triangle in Figure 8(b)).

[0073] As a result, the charge / discharge control unit 30 can control the amount of charge stored in the battery 3 based on the charge / discharge command value obtained from the corrected energy storage plan data, without having to wait until the next plan update timing T2. Moreover, the corrected energy storage plan data is new energy storage plan data that gradually changes the charge / discharge command value so that the actual amount of charge stored in the battery 3 matches the energy storage plan data at the next plan update timing T2. Therefore, even if an error greater than a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in the battery 3, rapid charging and discharging of the battery 3 can be suppressed, so that the amount of charge stored in the battery 3 does not fluctuate greatly, and the battery 3 can be charged without discharging the battery 3 to match the amount of charge stored in the battery 3 to the energy storage plan data at the next plan update timing T2. Thus, unnecessary charging and discharging of the battery 3 can be suppressed, and damage to the battery 3 and degradation can be suppressed.

[0074] Furthermore, within the period from the plan update timing T1 to the next plan update timing T2, in Embodiment 1, as shown in Figure 5(a), a rapid discharge of battery 3 occurs followed by a rapid charge, resulting in repeated rapid charging and discharging of battery 3. However, in this embodiment, as shown in Figure 8(a), after suppressing the initial rapid charge or discharge of battery 3, rapid charging and discharging of battery 3 can be suppressed. Therefore, the configuration of this embodiment is particularly effective when rapid charging and discharging of battery 3 occurs frequently.

[0075] As shown in Figure 8(b), the energy storage planning unit 114 generates new energy storage planning data (corrected energy storage planning data) that corrects the charge / discharge command value so that the actual amount of energy stored in the battery 3 is greater than the lower limit of the charging depth and less than the charge / discharge command value, and that it matches the energy storage planning data and changes gradually at the next planning update timing T2. The charge / discharge command generation unit 115 generates charge / discharge command values ​​based on the corrected energy storage planning data. The charge / discharge control unit 30 generates charge / discharge commands based on the charge / discharge command values ​​obtained from the corrected energy storage planning data. This makes it possible to suppress large fluctuations in the actual amount of energy stored in the battery 3.

[0076] In this embodiment, the charge / discharge command value based on the corrected energy storage plan data is set at the timing when the error between the charge / discharge command value and the actual amount of charge stored in the battery 3 exceeds a predetermined value, within the period from the plan update timing T1 to the next plan update timing T2, as indicated by the black triangle in Figure 8(b). However, the charge / discharge command value based on the corrected energy storage plan data may also be set to gradually change the amount of charge stored in the battery 3 over a shorter period than the plan update timing, within the period from the plan update timing T1 to the next plan update timing T2, as indicated by the black triangle in Figure 9(b). In this case, for example, if an error exceeding a predetermined amount occurs between the charge / discharge command value and the actual amount of charge stored in battery 3 before the plan update timing T1, new energy storage plan data (corrected energy storage plan data) is generated by pre-correcting the charge / discharge command value during the period from plan update timing T1 to the next plan update timing T2. As shown in Figure 9(b), this suppresses the accumulation of errors between the charge / discharge command value and the actual amount of charge stored in battery 3 from the time of plan update timing T1, and as shown in Figure 9(a), it suppresses the occurrence of rapid charging and discharging of battery 3, thereby further suppressing damage and deterioration of battery 3.

[0077] The energy storage planning unit 114, when an error greater than a predetermined value occurs between the charge / discharge command value based on the energy storage planning data and the actual amount of energy stored in the battery 3, and the actual amount of energy stored in the battery 3 is less than or equal to the lower limit of the charging depth, prioritizes making the amount of energy stored in the battery 3 greater than the lower limit of the charging depth, and generates the corrected energy storage planning data so that it is greater than the lower limit of the charging depth and close to the lower limit of the charging depth, as shown by the white triangle in Figure 9(b). This makes it possible to control the charging and discharging of the battery 3 so that the amount of energy stored in the battery 3 is greater than the lower limit of the charging depth. Therefore, the actual amount of energy stored in the battery 3 can be made greater than the lower limit of the charging depth, and damage and deterioration of the battery 3 can be suppressed.

[0078] Furthermore, the charge / discharge command value based on the corrected energy storage plan data may be set to any value as long as the amount of energy stored in battery 3 is greater than the lower limit of the charging depth and less than the upper limit of the charging depth, and is close to the charge / discharge command value.

[0079] Furthermore, the charge / discharge command generation unit 115 may, in conjunction with the control described above, change the lower limit of the charge depth of the battery 3, similar to the charge / discharge command generation unit 15 in Embodiment 1. This allows for effective utilization of the battery's storage capacity and prevents the maximum demand power (demand value) from being updated even if the battery 3 is charged or discharged with power exceeding the contracted power when a rapid charge / discharge occurs. The charge / discharge command generation unit 115 can also minimize the period during which the actual charge level of the battery 3 is below the lower limit of the charge depth by returning the battery's storage level to the original lower limit of the charge depth when the battery's storage level exceeds the original lower limit of the charge depth. This reduces damage and degradation of the battery 3 compared to the case where the lower limit of the charge depth of the battery 3 is not returned to its original value.

[0080] (Other embodiments) Although embodiments of the present invention have been described above, the embodiments described above are merely examples for carrying out the present invention. Therefore, the invention is not limited to the embodiments described above, and it is possible to carry out the invention by appropriately modifying the embodiments described above without departing from the spirit of the invention.

[0081] In each of the above embodiments, when the upper limit of the charging depth is changed to a value higher than the original value, or when the lower limit of the charging depth is changed to a value lower than the original value, the energy storage system 100 may have an energy storage unit that reduces the input and output current to the battery 3. The energy storage unit includes a capacitor, another battery, a configuration that can store electrical energy by mechanical energy or potential energy, etc. The energy storage unit is electrically connected in parallel with the battery 3. This makes it possible to improve the charge and discharge performance of the energy storage system 100 while reducing the input and output current to the battery 3.

[0082] In each of the above embodiments, when the upper limit of the charging depth is changed to a value higher than the original value, or when the lower limit of the charging depth is changed to a value lower than the original value, the energy storage system 100 may have a cooling unit that suppresses heat generation during charging and discharging of the battery 3. The cooling unit includes a cooling element (heat sink, fan, Peltier element, etc.), a heat exchanger, etc. This makes it possible to improve the charging and discharging performance of the energy storage system 100 while suppressing heat generation during charging and discharging of the battery 3. Preferably, the cooling unit operates only when the upper limit of the charging depth is changed to a value higher than the original value, or when the lower limit of the charging depth is changed to a value lower than the original value. This makes it possible to reduce power consumption compared to when the cooling unit is constantly running.

[0083] In the embodiments described above, the case where the amount of charge stored in the battery 3 falls below the lower limit of the charging depth was explained. However, even when the amount of charge stored in the battery 3 exceeds the upper limit of the charging depth, similar effects can be obtained by correcting the charge / discharge command value using the charge / discharge command generation units 15 and 115 so that the charge / discharge command value is smaller than the upper limit of the charging depth and larger than the lower limit of the charging depth.

[0084] In this case, in the configuration of Embodiment 1, for example, if an error greater than a predetermined amount occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3, and the actual amount of energy stored in the battery 3 is greater than or equal to the upper limit of the depth of charge, the charge / discharge command value (corrected charge / discharge command value) is corrected so that the amount of energy stored in the battery 3 becomes less than the upper limit of the depth of charge.

[0085] In the configuration of Embodiment 2, for example, if an error greater than a predetermined amount occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3, and the actual amount of energy stored in the battery 3 is greater than or equal to the upper limit of the charging depth, the energy storage plan unit 114 generates corrected energy storage plan data so that the amount of energy stored in the battery 3 is less than the upper limit of the charging depth and close to the upper limit of the charging depth.

[0086] In the embodiments described above, the case in which the charge / discharge command generation units 15 and 115 change the lower limit of the charge depth of the battery 3 has been explained. However, the charge / discharge command generation unit may also change the upper limit of the charge depth. This allows the charging and discharging of the battery 3 to be controlled using a range higher than the upper limit of the charge depth of the battery 3, thereby enabling effective utilization of the battery 3. Furthermore, when the amount of charge stored in the battery 3 falls below the original upper limit of the charge depth, the charge / discharge command generation unit returns it to the original upper limit of the charge depth, thereby minimizing the period during which the actual amount of charge stored in the battery 3 is above the upper limit of the charge depth. This suppresses damage and degradation of the battery 3 compared to the case in which the upper limit of the charge depth of the battery 3 is not returned to its original value.

[0087] In each of the above embodiments, if an error greater than a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery 3, the charge / discharge command value is corrected in each embodiment to control the charging and discharging of the battery 3. However, if, for example, the prediction error of the power generation prediction unit or the power demand prediction unit is larger than expected and it can be anticipated in advance that a rapid charging and discharging of the battery will occur, the configuration of each embodiment may be applied regardless of whether an error greater than a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery.

[0088] In the above embodiment 1, the charge / discharge control unit 30 controls the drive of the DC / AC converter 4 based on the energy storage plan data. However, the charge / discharge control unit 30 may also control the drive of the power generation unit based on the energy storage plan data. Alternatively, the charge / discharge control unit 30 may directly control the input and output of current to the battery.

[0089] In the above embodiment 1, an example of the configuration of the energy storage planning unit 14 was shown and explained in Figure 3, but the configuration of the energy storage planning unit can be any configuration as long as it is capable of generating energy storage planning data.

[0090] In the second embodiment, the energy storage planning unit 114 may also generate energy storage planning data by machine learning (AI processing), similar to the energy storage planning unit 14 in the first embodiment. Furthermore, among the energy storage control units 10 and 110 in each embodiment, components other than the energy storage planning units 14 and 114 may have configurations that can be processed by machine learning (AI processing). [Industrial applicability]

[0091] This invention can be used in an energy storage control device that controls the amount of energy stored in a battery based on energy storage plan data. [Explanation of Symbols]

[0092] 1. Energy storage control device 2. Power Generation Section 3 Batteries 4 DC / AC converter 10, 110 Energy Storage Control Unit 11 Power generation measurement data storage unit 12 Demand Measurement Data Storage Unit 13 Battery charge / discharge data storage unit 14, 114 Energy Storage Planning Department 15, 115 Charge / discharge command generation unit 21 Power Generation Forecasting Section 22 Power generation prediction error calculation unit 23. Electricity Demand Forecasting Department 24. Electricity Demand Forecast Error Calculation Unit 25 Battery charge level calculation unit 26 Energy Storage Plan Generation Unit 30 Charge / Discharge Control Unit 50 Power consumption part 100 Energy Storage Systems T1, T2 Plan Update Timing

Claims

1. A power storage control unit having a power storage planning unit that generates power storage planning data, which is data relating to the planning of battery storage, based on a predicted power generation value, a predicted power demand value, and the amount of charge stored in a battery that charges and discharges power, and a charge / discharge command generation unit that generates charge / discharge command values ​​based on the power storage planning data, A charge / discharge control unit that controls the charging and discharging of the battery based on the energy storage plan data, It has, The charge / discharge command generation unit corrects the charge / discharge command value based on the error if an error occurs between the charge / discharge command value generated based on the energy storage plan data and the amount of energy stored in the battery. Energy storage control device.

2. In the energy storage control device according to claim 1, The charge / discharge command generation unit corrects the charge / discharge command value so that, if an error greater than a predetermined value occurs between the charge / discharge command value in the energy storage plan data and the actual amount of energy stored in the battery, and the actual amount of energy stored in the battery is greater than or equal to the upper limit of the charging depth or less than or equal to the lower limit of the charging depth, the actual amount of energy stored in the battery is less than the upper limit of the charging depth and greater than the lower limit of the charging depth. Energy storage control device.

3. In the energy storage control device according to claim 1, If an error exceeding a predetermined value occurs between the charge / discharge command value based on the energy storage plan data and the actual amount of energy stored in the battery, the charge / discharge command generation unit corrects the charge / discharge command value so that the actual amount of energy stored in the battery matches the energy storage plan data at the next plan update timing and changes gradually within the period until the next plan update timing. Energy storage control device.

4. In the energy storage control device according to claim 1, If the energy storage planning unit detects an error exceeding a predetermined value between the charge / discharge command value based on the energy storage planning data and the actual amount of energy stored in the battery, it generates new energy storage planning data that changes the charge / discharge command value so that the actual amount of energy stored in the battery matches the energy storage planning data at the next planning update timing. Energy storage control device.

5. A rechargeable battery, A power generation unit that outputs the generated electricity to the battery, A power storage control device according to any one of claims 1 to 4, Having, Energy storage system.

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