JP2023013836A - Storage battery control device, storage battery control system, and storage battery control program - Google Patents

Abstract

To perform peak shaving on power received from a power system using a storage battery while controlling the amount of charge of the storage battery so that the peak shaving is not disabled.SOLUTION: A storage battery control device 10 performs control of: acquiring a demand prediction value indicative of a prediction value of power demand of a load 30 and a power generation prediction value indicative of a prediction value of the amount of power generated by a non-utility power generator 40; on the basis of the acquired demand prediction value and power generation prediction value, calculating a power reception upper limit indicative of an upper limit of system power received from a power system 60; and, when a demand actual value indicative of an actual value of the power demand of the load 30 exceeds the calculated power reception upper limit, discharging power corresponding to the difference between the demand actual value and the power reception upper limit from a storage battery 20. When the demand actual value is equal to or lower than the power reception upper limit and a power generation actual value indicative of an actual value of the amount of power generated by the non-utility power generator 40 is lower than the power generation prediction value, the storage battery control device performs control of charging the storage battery 20 from the power system 60 with insufficient power corresponding to the difference between the power generation prediction value and the power generation actual value.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a storage battery control device, a storage battery control system, and a storage battery control program, and more particularly, to a storage battery control device, a storage battery control system, and a storage battery control program that perform peak cut of received power using a storage battery.

2. Description of the Related Art In recent years, from the viewpoint of energy saving, etc., there is an increasing need for peak cut of power supplied from a power system. By performing peak shaving, it is possible to reduce the amount of power consumed during the day when the amount of power consumed by the customer is the highest.

For example, Patent Literature 1 describes a control device for a power storage device that includes a peak cut level updating device. This peak cut level update device compares the charge amount of the power storage device with the load power pattern, and updates the peak cut level indicating the upper limit value of the power received from the power system, or the discharge amount of the power storage device. and the discharge schedule to update the peak cut level.

JP-A-2000-69673

According to the prior art described in Patent Document 1, it is possible to suppress the power received from the electric power system to a predetermined level or less and efficiently discharge the power storage device (that is, the storage battery).

On the other hand, the peak cut level is determined based on the prediction of power demand by load. However, the power demand forecast and the actual power demand record do not always match. Therefore, it is not always possible to cut the peak as planned. For example, when a private power generator and a storage battery are installed side by side and the storage battery is planned to be charged, the amount of charge will decrease from the beginning due to reasons such as an increase in power demand or a decrease in the amount of power generated. Then, the peak cut by the storage battery becomes impossible. In the technique described in Patent Document 1, the peak cut level is updated irregularly, but the combination with a private power generator is not taken into consideration.

The present disclosure has been made in view of the above circumstances, and when using a storage battery to cut the peak of the power received from the power system, it is possible to control the charge amount of the storage battery so that the peak cut is not possible. It is an object of the present invention to provide a storage battery control device, a storage battery control system, and a storage battery control program that can

To achieve the above object, a storage battery control device according to a first aspect is a storage battery control device that controls charging and discharging of a storage battery connected to a power line to which power is supplied from a power system, the storage battery control device being connected to the power line. an acquisition unit that acquires a demand forecast value that indicates a forecast value of the power demand of the load, and a power generation forecast value that indicates a forecast value of the amount of power generated by the generator connected to the power line; and the demand acquired by the acquisition unit. a calculation unit for calculating a power reception upper limit value indicating an upper limit value of power received from the electric power system based on the predicted value and the power generation predicted value; When the calculated upper limit of power reception is exceeded, control is performed to discharge electric power corresponding to the difference between the actual demand value and the upper limit of power reception, and when the actual demand value is equal to or less than the upper limit of power reception, Further, when the actual power generation value indicating the actual value of the amount of power generated by the generator is less than the predicted power generation value, the shortage of electric power corresponding to the difference between the predicted power generation value and the actual power generation value is supplied from the power system. and a control unit that controls charging of the storage battery.

Further, in the storage battery control device according to the second aspect, in the storage battery control device according to the first aspect, the amount of charge to be charged from the power system is the amount of power obtained by subtracting the actual power generation value from the predicted power generation value, It is the power amount obtained by subtracting the actual power reception value indicating the actual value of power received from the power system from the power reception upper limit value, or the power amount that can be input to the storage battery, whichever is smaller.

Further, a storage battery control device according to a third aspect is the storage battery control device according to the first aspect or the second aspect, wherein when the actual power generation value is greater than the actual demand value, Control for charging the storage battery with surplus power corresponding to the difference from the actual demand value from the generator, control for reverse power flow of the surplus power from the generator to the power system, or control for reducing the output of the generator I do.

Further, a storage battery control device according to a fourth aspect is the storage battery control device according to any one of the first to third aspects, when the calculation unit reserves part of the capacity of the storage battery, A safety factor indicating the proportion of the spare is acquired, and the upper limit of power reception is calculated based on the predicted demand value, the predicted power generation value, and the safety factor.

Furthermore, in order to achieve the above object, a storage battery control system according to a fifth aspect includes a storage battery connected to a power line to which power is supplied from a power system, and a storage battery control device that controls charging and discharging of the storage battery. wherein the storage battery control device has a demand forecast value indicating a forecast value of power demand of the load connected to the power line, and a forecast value of the amount of power generated by the generator connected to the power line. and a calculation unit that calculates a power reception upper limit value that indicates the upper limit of the power received from the power system based on the predicted demand value and the predicted power generation value that are obtained by the obtaining unit. and, when the actual demand value indicating the actual value of the power demand of the load exceeds the upper limit of power reception calculated by the calculating unit, the power equivalent to the difference between the actual demand value and the upper limit of power reception is The power generation prediction is performed when the actual demand value is equal to or less than the upper limit of power reception and the actual power generation value indicating the actual value of the amount of power generated by the generator is less than the predicted power generation value. a control unit that performs control to charge the storage battery with a shortage of electric power corresponding to the difference between the value and the actual power generation value from the electric power system.

Furthermore, in order to achieve the above object, a storage battery control program according to a sixth aspect causes a computer to function as each unit included in the storage battery control device according to any one of the first to fourth aspects.

As described in detail above, according to the technology of the present disclosure, when the storage battery is used to cut the peak of the power received from the power system, it is possible to control the charge amount of the storage battery so that the peak cut is not possible. , has the effect of

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows an example of a structure of the storage battery control system which concerns on 1st Embodiment. 1 is a block diagram showing an example of an electrical configuration of a storage battery control device according to a first embodiment; FIG. It is a figure which shows typically an example of the peak cut which concerns on embodiment. It is a figure which shows typically another example of peak cut in embodiment. It is a block diagram showing an example of functional composition of a storage battery control device concerning a 1st embodiment. 4 is a flow chart showing an example of the flow of processing by a storage battery control program according to the first embodiment; 7 is a flowchart showing an example of the flow of power reception upper limit value calculation processing according to the first embodiment; It is a figure which shows an example of the charge amount with which a storage battery is charged from the electric power system which concerns on embodiment. FIG. 7 is a diagram for explaining a calculation example when calculating a power reception upper limit value based on a demand forecast value; FIG. 7 is a diagram for explaining a calculation example when calculating a power reception upper limit value based on a demand forecast value; FIG. 7 is a diagram for explaining a calculation example when calculating a power reception upper limit value based on a demand forecast value; FIG. 7 is a diagram for explaining a calculation example when calculating a power reception upper limit value based on a demand forecast value; FIG. 10 is a diagram for explaining an example of calculation when a power reception upper limit value is calculated based on a demand forecast value and a power generation forecast value; FIG. 10 is a diagram for explaining an example of calculation when a power reception upper limit value is calculated based on a demand forecast value and a power generation forecast value; FIG. 10 is a diagram for explaining an example of calculation when a power reception upper limit value is calculated based on a demand forecast value and a power generation forecast value; FIG. 10 is a diagram for explaining an example of calculation when a power reception upper limit value is calculated based on a demand forecast value and a power generation forecast value; FIG. 10 is a diagram for explaining an example of calculation when a power reception upper limit value is calculated based on a demand forecast value and a power generation forecast value; FIG. 11 is a flow chart showing an example of the flow of power reception upper limit value calculation processing including ensuring a safety factor according to the second embodiment; FIG.

Hereinafter, an example of a mode for implementing the technology of the present disclosure will be described in detail with reference to the drawings. Components and processes having the same actions, actions, and functions are given the same reference numerals throughout the drawings, and overlapping descriptions may be omitted as appropriate. Each drawing is only schematically shown to the extent that the technology of the present disclosure can be fully understood. Therefore, the technology of the present disclosure is not limited only to the illustrated examples. Further, in the present embodiment, descriptions of configurations that are not directly related to the technology of the present disclosure and well-known configurations may be omitted.

[First Embodiment]
FIG. 1 is a diagram showing an example of the configuration of a storage battery control system 100 according to the first embodiment.

As shown in FIG. 1 , a storage battery control system 100 according to this embodiment includes a storage battery control device 10 , a storage battery 20 , a load 30 , a private power generator 40 and a server 50 . Storage battery 20 , load 30 , and private generator 40 are connected to power line 70 . Power is supplied to the power line 70 from the power system 60 .

The storage battery 20 is a rechargeable secondary battery, and the storage battery 20 is, for example, a lithium ion battery, a lead storage battery, or the like.

The load 30 is an electrical device or the like used by a consumer, and the specific type and number of the electrical device or the like are not particularly limited.

The private power generator 40 may be, for example, a power generation device using natural energy such as photovoltaic power generation (solar battery) or wind power generation, or a power generation device using regenerative energy. Private power generator 40 is an example of a power generator.

The power from power system 60 , the power discharged from storage battery 20 , and the power generated by private power generator 40 are all supplied to power line 70 . The power used by the load 30 and the total amount of power supplied from the power system 60, the storage battery 20, and the private generator 40 to the power line 70 are in balance, and the supply and demand balance is maintained.

The server 50 predicts the power demand of the load 30 and the power generation amount of the private power generator 40 . Specifically, the server 50 calculates a demand forecast value indicating the forecast value of the power demand of the load 30 based on the past power demand record of the load 30, and predicts power generation indicating the forecast value of the amount of power generated by the private power generator 40. The value is calculated based on the past record of power generation amount of private power generator 40 . The server 50 provides the storage battery control device 10 with the predicted demand value of the load 30 and the predicted power generation value of the private power generator 40 obtained by calculation.

The storage battery control device 10 outputs a control command signal to the storage battery 20 to control charging and discharging of the storage battery 20 . The storage battery control device 10 acquires the amount of charge to the storage battery 20 and the amount of discharge from the storage battery 20 from an arbitrary connection point provided on the power line 70 between the power system 60 and the storage battery 20 . The storage battery control device 10 also calculates the upper limit of power reception based on the predicted demand value of the load 30 and the predicted power generation value of the private power generator 40 provided from the server 50 . The power reception upper limit here indicates the upper limit of the power received from the power system 60 . In addition, when performing peak cut, the storage battery control device 10 uses the actual demand value indicating the actual value of the power demand of the load 30, the remaining amount of storage battery indicating the remaining power amount of the storage battery 20, and the power generation by the private power generator 40. Get the actual power generation value that indicates the actual value of the amount. Note that the actual demand value is obtained from an arbitrary connection point provided on the power line 70 between the power system 60 and the load 30, and the actual power generation value is obtained from the power line 70 between the power system 60 and the private generator 40. obtained from any linking point provided in

In this embodiment, the storage battery control device 10 and the server 50 are configured separately. may

FIG. 2 is a block diagram showing an example of the electrical configuration of the storage battery control device 10 according to the first embodiment.

As shown in FIG. 2, the storage battery control device 10 according to the present embodiment includes a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, a RAM (Random Access Memory) 13, and an input/output interface (I /O) 14 , a storage unit 15 , a communication unit 16 , and an external interface (hereinafter referred to as “external I/F”) 17 .

The CPU 11, ROM 12, RAM 13, and I/O 14 are each connected via a bus. Functional units including a storage unit 15 , a communication unit 16 and an external I/F 17 are connected to the I/O 14 . Each of these functional units can communicate with the CPU 11 via the I/O 14 .

As the storage unit 15, for example, an HDD (Hard Disk Drive), an SSD (Solid State Drive), a flash memory, or the like is used. Storage unit 15 stores storage battery control program 15A for controlling charging and discharging of storage battery 20 . In addition, this storage battery control program 15A may be stored in the ROM 12 .

The storage battery control program 15A may be pre-installed in the storage battery control device 10, for example. The storage battery control program 15A may be stored in a non-volatile storage medium or distributed via a network and installed in the storage battery control device 10 as appropriate. Examples of nonvolatile storage media include CD-ROMs (Compact Disc Read Only Memory), magneto-optical discs, HDDs, DVD-ROMs (Digital Versatile Disc Read Only Memory), flash memories, memory cards, and the like. be.

The communication unit 16 is connected to a network such as the Internet, a LAN (Local Area Network), or a WAN (Wide Area Network), and can communicate with the server 50 via the network.

A storage battery 20 and a private power generator 40 are connected to the external I/F 17 . Via external I/F17, these storage battery 20 and private generator 40 are connected so that CPU11 and communication are possible.

In this embodiment, as shown in FIGS. 3 and 4, the storage battery 20 is used to perform peak cut of the power received from the power system 60 .

FIG. 3 is a diagram schematically showing an example of peak cut according to this embodiment. In FIG. 3, the vertical axis indicates power [kW] and the horizontal axis indicates time.

In the peak cut shown in FIG. 3, when the actual power demand PL exceeds the power reception upper limit, control is performed so that the amount exceeding the power reception upper limit is discharged from the storage battery 20 . Note that in FIG. 3 , the portion hatched with dotted lines indicates the amount of charge to the storage battery 20, which is charged from the power system 60 at night. Further, the hatched portion of the solid line indicates the discharge amount (peak cut amount) from the storage battery 20, and the amount equal to the charge amount is discharged.

FIG. 4 is a diagram schematically showing another example of peak cut in this embodiment. In FIG. 4, the vertical axis indicates power [kW] and the horizontal axis indicates time.

As shown in FIG. 4 , when the amount of power generated by the private power generator 40 is greater than the actual power demand PL, the surplus amount of power generation may be charged from the private power generator 40 to the storage battery 20 . As a result, reverse power flow to the power system 60 can be prevented, and the self-consumption rate of generated power can be increased. In addition, in FIG. 4 , the portion hatched with dotted lines indicates the amount of charge to charge the storage battery 20 from the private power generator 40 . Further, the hatched portion of the solid line indicates the discharge amount (peak cut amount) from the storage battery 20, and the amount equal to the charge amount is discharged.

Here, the power reception upper limit value is determined based on the power demand prediction of the load 30 and the power generation amount prediction of the private power generator 40 obtained from the server 50 . However, the power demand forecast and the actual power demand performance do not always match, and similarly, the power generation forecast and the actual power generation performance do not always match. Therefore, it is not always possible to cut the peak as planned. For example, as described above, when the private power generator 40 and the storage battery 20 are installed side by side and the storage battery 20 is planned to be charged, the power demand increases or the amount of power generation decreases. If the charge amount decreases further, the peak cut by the storage battery cannot be performed.

In this embodiment, even if the power demand forecast and the actual power demand performance do not match, as much peak cut as possible is performed, and if the power demand forecast is off, it is possible to approach the ideal amount of peak cut as much as possible. Provide control logic that allows Specifically, when the amount of charge from the private power generator 40 to the storage battery 20 decreases, control is performed to charge the power system 60 with the amount of the decrease.

Therefore, the CPU 11 of the storage battery control device 10 according to the present embodiment writes the storage battery control program 15A stored in the storage unit 15 into the RAM 13 and executes it, thereby functioning as each unit shown in FIG.

FIG. 5 is a block diagram showing an example of a functional configuration of the storage battery control device 10 according to the first embodiment.

As shown in FIG. 5, the CPU 11 of the storage battery control device 10 according to this embodiment functions as an acquisition unit 11A, a calculation unit 11B, and a charge/discharge control unit 11C. Note that the charge/discharge control unit 11C is an example of a control unit.

Acquisition unit 11A acquires a demand forecast value of load 30 connected to power line 70 . In addition, the acquisition unit 11A acquires the predicted power generation value of the private power generator 40 . The predicted demand value and predicted power generation value may be obtained directly from the server 50, or the predicted demand value and predicted power generation value obtained from the server 50 may be temporarily stored in the storage unit 15 and then obtained from the storage unit 15. . Note that when the demand forecast is performed continuously for 24 hours, that is, all day long, the time zone for performing the demand forecast is not particularly limited. On the other hand, the demand forecast may be limited to a predetermined time period. In this case, the predetermined time period is a time period during which power demand is relatively high in one day, for example, the time period from 10:00 to 16:00. The acquisition unit 11A also acquires the actual demand value of the load 30 and the remaining amount of the storage battery 20 .

The calculation unit 11B calculates the power reception upper limit value based on the predicted demand value and the predicted power generation value acquired by the acquisition unit 11A. In this case, the calculated power reception upper limit value is not updated. In addition, it is desirable to consider the remaining amount of the storage battery in calculating the power reception upper limit.

Further, calculation unit 11B acquires the maximum received power value indicating the maximum amount of power received from power system 60 in a predetermined period, and if the upper limit of received power is equal to or less than the maximum received power value, calculation unit 11B sets the maximum received power value to the maximum received power value. may be The predetermined period here is, for example, the period from the first day of the current month (the month in which the peak cut is performed) to the day when the peak cut is performed. As an example, when the peak cut is performed on April 10th, the predetermined period is 10 days from April 1st to April 10th. Also, the maximum received power value may be obtained by storing history information of the amount of power received from the power system 60 in the storage unit 15 and obtaining the maximum value from the history information stored in the storage unit 15 .

When the actual demand value of the load 30 exceeds the upper limit of power reception calculated by the calculating unit 11B, the charge/discharge control unit 11C discharges electric power corresponding to the difference between the actual demand value and the upper limit of power reception from the storage battery 20. control. The amount of discharge discharged from the storage battery 20 is the amount of power obtained by subtracting the upper limit of power reception from the power reception actual value indicating the actual value of the power received from the power system 60, or the amount of power that can be output from the storage battery 20, whichever is smaller. It is said that

Further, when the actual demand value of the load 30 is equal to or less than the power reception upper limit value and the actual power generation value of the private power generator 40 is less than the predicted power generation value, the charge/discharge control unit 11C determines the difference between the predicted power generation value and the actual power generation value. Control is performed to charge the storage battery 20 with the power shortage corresponding to the difference from the power system 60 . The amount of charge to be charged from the power system 60 is the amount of power obtained by subtracting the actual power generation value from the predicted power generation value, the amount of power obtained by subtracting the actual power reception value from the upper limit power reception value, and the amount of power that can be input from the storage battery 20. whichever is smaller.

As described above, when the amount of charge from the private power generator 40 to the storage battery 20 decreases, control is performed so that the electric power system 60 charges the amount of the decrease.

That is, when the amount of charge in the storage battery 20 is less than the initial amount due to reasons such as an increase in power demand or a decrease in the amount of power generated, the difference is compensated for by charging from the power system 60 . In charging the difference from the power system 60 to the storage battery 20, as described above, the amount of power obtained by subtracting the actual power generation value from the predicted power generation value, the amount of power obtained by subtracting the actual power reception value from the upper limit power reception value, and the amount of electric power that can be input to the storage battery 20, whichever is smaller. In other words, charging is controlled so as not to exceed the power reception upper limit. For example, in order to prevent a situation in which the amount of photovoltaic power generation is less than expected and the storage battery 20 cannot be charged, peak cut after the evening cannot be performed, the power system 60 charges the insufficient amount.

Further, as shown in FIG. 4 described above, when the actual power generation value of the private power generator 40 is greater than the actual demand value of the load 30, the charge/discharge control unit 11C corresponds to the difference between the actual power generation value and the actual demand value. Alternatively, control may be performed to charge the storage battery 20 with the surplus power generated from the private power generator 40 . Note that when the storage battery 20 is in a fully charged state, the charge/discharge control unit 11C controls the reverse flow of surplus power from the private power generator 40 to the power system 60, or reduces the output of the private power generator 40. control to allow

Next, operation of the storage battery control device 10 according to the first embodiment will be described with reference to FIG.

FIG. 6 is a flow chart showing an example of the flow of processing by the storage battery control program 15A according to the first embodiment.

When a storage battery control instruction is issued to the storage battery control device 10, the storage battery control program 15A stored in the storage unit 15 is activated by the CPU 11, and the following steps are executed.

In step S101 of FIG. 6, the CPU 11 performs calculation of the power reception upper limit (power reception upper limit calculation process) as shown in FIG. 7, for example.

FIG. 7 is a flowchart showing an example of the flow of power reception upper limit value calculation processing according to the first embodiment, and shows a subroutine of step S101 in FIG.

In step S111 of FIG. 7, the CPU 11 determines the upper limit of received power (provisional) from the predicted demand value of the load 30 and the predicted power generation value of the private power generator 40 .

In step S112, the CPU 11 acquires the maximum value of received power at the current point in the current month. That is, as described above, for example, the maximum received power value in the period from the first day of the current month (the month in which peak cut was performed) to the day when peak cut was performed is acquired.

In step S113, the CPU 11 determines whether or not the power reception upper limit value (provisional) is greater than the power reception maximum value. If it is determined that the power reception upper limit value (provisional) is greater than the maximum power reception value (in the case of affirmative determination), the process proceeds to step S114, and if it is determined that the power reception upper limit value (provisional) is equal to or less than the maximum power reception value (in the case of a negative determination). , the process proceeds to step S115.

In step S114, the CPU 11 sets the power reception upper limit value (provisional) as the power reception upper limit value, and returns to step S102 in FIG.

In step S115, the CPU 11 sets the received power maximum value to the received power upper limit value, and returns to step S102 in FIG.

Returning to FIG. 6, in step S102, the CPU 11 determines whether or not the actual demand value of the load 30 is greater than the power reception upper limit value. If it is determined that the actual demand value is greater than the power reception upper limit value (in the case of affirmative determination), the process proceeds to step S103, and if it is determined that the actual demand value is equal to or less than the power reception upper limit value (in the case of a negative determination), the process proceeds to step S105. do.

In step S<b>103 , the CPU 11 performs control to discharge the storage battery 20 . As described above, the amount of power discharged from the storage battery 20 is the amount of power obtained by subtracting the upper limit of received power from the actual received power value, or the amount of power that can be output from the storage battery 20, whichever is smaller. be done.

In step S104, the CPU 11 determines whether or not the remaining battery level of the storage battery 20 has reached 0 (zero). When it is determined that the remaining battery level of the storage battery 20 does not become 0 (in the case of a negative determination), the process returns to step S102 and the process is repeated, and when it is determined that the remaining battery level of the storage battery 20 has become 0 (in the case of affirmative determination), A series of processes by the storage battery control program 15A is ended.

In step S105, the CPU 11 determines whether or not the actual power generation value of the private power generator 40 is less than the predicted power generation value. When it is determined that the actual power generation value is less than the predicted power generation value (in the case of affirmative determination), the process proceeds to step S106, and when it is determined that the actual power generation value is equal to or greater than the predicted power generation value (in the case of a negative determination), the storage battery 20 is discharged. Without returning to step S102, the processing is repeated.

In step S106, the CPU 11 performs control to charge the storage battery 20 with the power shortage corresponding to the difference between the predicted power generation value and the actual power generation value from the electric power system 60, and proceeds to step S104. As described above, the amount of charge to be charged from the power system 60 is the amount of power obtained by subtracting the actual power generation value from the predicted power generation value, the amount of power obtained by subtracting the actual power reception value from the upper limit power reception value, and , the amount of power that can be input to the storage battery 20, whichever is smaller.

FIG. 8 is a diagram showing an example of the amount of charge that the storage battery 20 is charged from the power system 60 according to this embodiment.

As shown in FIG. 8, when the surplus of the amount of power generated by the private power generator 40 is smaller than expected and the storage battery 20 cannot be sufficiently charged by the private power generator 40 alone, the difference is compensated for by charging from the electric power system 60. You may do so. In FIG. 8 , the alternate long and short dash line indicates the initially scheduled charge amount of the storage battery 20, and the solid line indicates the difference between the power generation amount and the power demand, that is, the surplus power generation amount. The difference between the power generation amount and the power demand (surplus power generation amount) and the difference between the scheduled charging amount (dotted line hatching) is the charging shortage of the storage battery 20 . This shortfall is supplemented by charging from the power system 60 .

Here, specific calculation examples will be described for each of (1) the case where the power reception upper limit value is calculated based on the demand forecast value and (2) the case where the power reception upper limit value is calculated based on the demand forecast value and the power generation forecast value.

9 to 12, a specific example of calculation when (1) the power reception upper limit value is calculated based on the demand forecast value will be described.

9 to 12 are diagrams for explaining calculation examples when the upper limit of power reception is calculated based on the demand forecast value.

As an example, assume the demand forecast shown in FIG. In order to simplify the explanation, the data is assumed to be hourly data, but it goes without saying that in actual use, the data may be data every 30 minutes. In the example of FIG. 9, the upper stage shows the time stamp, and the lower stage shows the demand forecast value (kW).

Assume that the storage battery capacity is 90 kWh as an example. This is the capacity of a typical commercial storage battery. PCS (Power Conditioning System) capacity is not considered here. Also, charging is not taken into account, only discharging is taken into account.

As an example, the power reception upper limit is provisionally set to 120 kW, and the demand prediction value exceeding 120 kW is discharged to reduce the power reception amount to 120 kW. In this case, the predicted demand value and required storage battery capacity after the operation of the storage battery are as shown in FIG. In the example of FIG. 10, the upper stage shows the time stamp, the middle stage shows the demand forecast value (kW), and the lower stage shows the amount of discharge from the storage battery.

In the example of FIG. 10, the total discharge amount from the storage battery is 10+20+10+30+40+30+20=160 kWh, which exceeds the storage battery capacity of 90 kWh. In this case, it is determined that the power reception upper limit is too low. Therefore, the power reception upper limit is temporarily set to 130 kW again, and similar calculations are performed. Calculation results are shown in FIG.

FIG. 12 is a graph showing the calculation results of FIG. That is, as shown in FIG. 12, the demand exceeding the provisionally set 130 kW is covered by discharging from the storage battery. In the example of FIGS. 11 and 12, the total amount of discharge from the storage battery is 10+20+30+20+10=90 kWh, which is equal to the storage battery capacity and is not appropriate because the surplus cannot be secured. Therefore, it is determined that 140 kW is appropriate for the power reception upper limit.

Next, with reference to FIGS. 13 to 17, (2) specific calculation examples in the case of calculating the power reception upper limit value based on the demand forecast value and the power generation forecast value will be described.

13 to 17 are diagrams for explaining calculation examples when the power reception upper limit value is calculated based on the demand forecast value and the power generation forecast value.

If the predicted demand value always exceeds the predicted power generation value, or if the amount of power generation that exceeds the predicted demand value (so-called surplus power) is reversed to the power system, the same calculation method as in (1) above. shall be the calculation method of In the case of charging the storage battery with the surplus power, a calculation method different from the above calculation method (1) is used.

As an example, assume the demand forecast and power generation forecast shown in FIG. The storage battery capacity is 90 kWh, which is the same as in (1) above, and surplus power is charged to the storage battery. In the example of FIG. 13, the first stage shows the time stamp, the second stage shows the demand forecast value (kW), the third stage shows the power generation forecast value (kW), and the fourth stage shows (demand forecast value - power generation forecast value). ing. Note that the value of "- (minus)" in the fourth row indicates surplus power.

In the example of FIG. 13, (-20)+(-20)+(-10)+(-10)=-60 kWh, and 60 kWh of surplus power is expected. Therefore, the remaining capacity of the storage battery is assumed to be 90-60=30 kWh. Considering the same as above (1), the power reception upper limit is 60 kW. Calculation results are shown in FIG.

FIG. 15 is a graph showing the calculation results of FIG. In the time period from 12:00 to 15:00, a total of 60 kWh of surplus power is expected, so it is necessary to keep the capacity of the storage battery free. However, the discharge shown in FIGS. 14 and 15 cannot be realized. The reason is that the remaining amount of the storage battery at the start of the day was 30 kWh, and it was not possible to cover the total discharge amount of 50 (=10 + 30 + 10) kWh during the period from 7:00 to 9:00. Therefore, the power reception upper limit value is increased, and the realizable power reception upper limit value is reset. FIG. 16 shows the calculation results when the power reception upper limit is set to 67 kW as an example.

FIG. 17 is a graph showing the calculation results of FIG. In other words, the maximum power reception upper limit is set that is greater than 60 kWh and that the total amount of discharge in the time period from 7:00 to 9:00 is within 30 kWh. Here, after 16:00, it is possible to discharge up to 67 kW or less, but since it does not contribute to the reduction of the contract power, discharging is optional.

As described above, according to the present embodiment, when the amount of charge from the private power generator to the storage battery decreases, control is performed so that the amount of the decrease is charged from the electric power system. Therefore, it is possible to control the charge amount of the storage battery so that peak cut is not impossible.

[Second embodiment]
In the power reception upper limit calculation process according to the first embodiment, the case where the power reception upper limit is determined from the demand forecast value and the power generation forecast value has been described. In the second embodiment, a case will be described in which the power reception upper limit value is determined from the demand forecast value, the power generation forecast value, and the safety factor.

Note that the components included in the storage battery control device according to the present embodiment are the same as the components included in the storage battery control device 10 according to the first embodiment. The differences will be explained with reference to .

When part of the capacity of the storage battery 20 is used as a spare, the calculation unit 11B acquires a safety factor indicating the proportion of the spare. The safety factor may be stored in advance in the storage unit 15, for example. For the safety factor, for example, an appropriate ratio is set within a range of 5% or more and 10% or less of the storage battery capacity. In this case, the calculation unit 11B calculates the power reception upper limit value based on the predicted demand value, the predicted power generation value, and the safety factor. In this case, it is desirable to calculate the power reception upper limit value in consideration of the remaining amount (charge amount) of the storage battery excluding the reserve charge amount. At this time, when the actual demand value is equal to or less than the power reception upper limit value, the reserve charge amount is not used, but when the demand actual value becomes larger than the power reception upper limit value, the reserve charge amount can be used.

FIG. 18 is a flowchart showing an example of the flow of power reception upper limit value calculation processing including safety factor ensuring according to the second embodiment, and shows the subroutine of step S101 in FIG. 6 described above.

In step S121 of FIG. 18, the CPU 11 determines the upper limit of received power (tentative) from the predicted demand value of the load 30, the predicted power generation value of the private power generator 40, and the safety factor of the storage battery 20. For the safety factor, as described above, an appropriate ratio is set within the range of 5% or more and 10% or less of the storage battery capacity, for example.

In step S122, the CPU 11 acquires the maximum value of received power at the current point in the current month. That is, as described above, for example, the maximum received power value in the period from the first day of the current month (the month in which peak cut was performed) to the day when peak cut was performed is acquired.

In step S123, the CPU 11 determines whether or not the power reception upper limit value (provisional) is greater than the power reception maximum value. If it is determined that the power reception upper limit value (provisional) is greater than the maximum power reception value (in the case of affirmative determination), the process proceeds to step S124, and if it is determined that the power reception upper limit value (provisional) is equal to or less than the maximum power reception value (in the case of a negative determination). , the process proceeds to step S125.

In step S124, the CPU 11 sets the power reception upper limit value (provisional) as the power reception upper limit value, and returns to step S102 in FIG. 6 described above.

In step S125, the CPU 11 sets the maximum received power value to the upper limit received power value, and returns to step S102 in FIG. 6 described above.

As described above, according to the present embodiment, the power reception upper limit value is calculated based on the demand forecast value, the power generation forecast value, and the safety factor, or the demand forecast value and the safety factor. Therefore, when the actual demand value becomes larger than the power reception upper limit value, it is possible to cope with the reserve charging amount according to the safety factor.

As described above, the storage battery control device and the storage battery control system have been exemplified as the above embodiments, but the embodiments may be in the form of programs for causing a computer to execute the functions of the units provided in the storage battery control device. Embodiments may be in the form of a computer-readable storage medium storing this program.

In addition, the configurations of the storage battery control device and the storage battery control system described in each of the above embodiments are examples, and may be changed depending on the situation without departing from the scope of the invention.

Further, the flow of processing of the programs described in each of the above embodiments is also an example, and unnecessary steps may be deleted, new steps added, or the processing order changed within the scope of the gist. good too.

Further, in each of the above-described embodiments, a case has been described in which the processing according to the embodiment is realized by a software configuration using a computer by executing a program, but the present invention is not limited to this. Embodiments may be implemented by, for example, a hardware configuration or a combination of hardware and software configurations.

10 storage battery control device 11 CPU
11A Acquisition unit 11B Calculation unit 11C Charge/discharge control unit 12 ROM
13 RAM
14 I/O
15 storage unit 15A storage battery control program 16 communication unit 17 external I/F
20 storage battery 30 load 40 private power generator 50 server 60 power system 70 power line 100 storage battery control system

Claims (6)

A storage battery control device that controls charging and discharging of a storage battery connected to a power line to which power is supplied from a power system,
an acquisition unit that acquires a predicted demand value indicating a predicted value of power demand of a load connected to the power line and a predicted power generation value indicating a predicted value of the amount of power generated by a generator connected to the power line;
a calculation unit that calculates a power reception upper limit value indicating an upper limit value of power received from the electric power system based on the predicted demand value and the predicted power generation value obtained by the obtaining unit;
When the actual demand value indicating the actual value of the power demand of the load exceeds the upper limit of power reception calculated by the calculation unit, power equivalent to the difference between the actual demand value and the upper limit of power reception is supplied from the storage battery. discharge control is performed, and when the actual demand value is equal to or less than the upper limit of power reception and the actual power generation value indicating the actual value of the amount of power generated by the generator is less than the predicted power generation value, the predicted power generation value and A control unit that performs control to charge the storage battery with the power shortage corresponding to the difference from the actual power generation value from the power system;
Storage battery control device with. The amount of charge to be charged from the power system is the power amount obtained by subtracting the actual power generation value from the predicted power generation value, and the power reception actual value indicating the actual power received from the power system is subtracted from the power reception upper limit value. 2 . The storage battery control device according to claim 1 , wherein the smaller of the amount of power obtained by the operation and the amount of power that can be input to the storage battery. When the actual power generation value is greater than the actual demand value, the control unit controls charging the storage battery with surplus power corresponding to the difference between the actual power generation value and the actual demand value from the generator or the surplus The storage battery control device according to claim 1 or 2, wherein control for reverse power flow of electric power from the generator to the power system or control for reducing the output of the generator is performed. The calculation unit acquires a safety factor indicating a ratio of the reserve when a part of the capacity of the storage battery is used as a reserve,
The storage battery control device according to any one of claims 1 to 3, wherein the power reception upper limit value is calculated based on the predicted demand value, the predicted power generation value, and the safety factor. a storage battery connected to a power line to which power is supplied from a power system;
a storage battery control device that controls charging and discharging of the storage battery;
A storage battery control system comprising
The storage battery control device
an acquisition unit that acquires a predicted demand value indicating a predicted value of power demand of a load connected to the power line and a predicted power generation value indicating a predicted value of the amount of power generated by a generator connected to the power line;
a calculation unit that calculates a power reception upper limit value indicating an upper limit value of power received from the electric power system based on the predicted demand value and the predicted power generation value obtained by the obtaining unit;
When the actual demand value indicating the actual value of the power demand of the load exceeds the upper limit of power reception calculated by the calculation unit, power equivalent to the difference between the actual demand value and the upper limit of power reception is supplied from the storage battery. discharge control is performed, and when the actual demand value is equal to or less than the upper limit of power reception and the actual power generation value indicating the actual value of the amount of power generated by the generator is less than the predicted power generation value, the predicted power generation value and A control unit that performs control to charge the storage battery with the power shortage corresponding to the difference from the actual power generation value from the power system;
storage battery control system. A storage battery control program for causing a computer to function as each unit included in the storage battery control device according to any one of claims 1 to 4.

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