Power control system and power control device

Abstract

To provide a power control system capable of appropriately discharging power from a power storage unit to an apparatus provided in a facility even when the peak of power demand varies from day to day.SOLUTION: A power control system 100 includes a power storage unit 30 that discharges power to an apparatus 2 in a store 1 and a control unit 10 that controls the discharge of the power storage unit 30. The control unit 10 stores, at predetermined time intervals, past power demand used in the store 1 in a storage unit 20. The control unit 10 extracts a peak time zone, during which the power demand peaks, from each of a plurality of days selected based on a predetermined criterion from among the past power demand stored in the storage unit 20. Further, the control unit 10 determines future timing for discharging power from the power storage unit 30 to the apparatus 2 based on the plurality of extracted peak time zones.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a power control system and a power control device, and more particularly to a power control system and a power control device for controlling a power storage unit that discharges power to devices in a facility.

Background Art

[0002] Conventionally, a power control system for controlling a power storage unit that discharges power to devices in a facility has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a facility controller that controls electrical equipment arranged for a tenant. Electrical equipment such as a power storage unit, lighting equipment, and air conditioning equipment is arranged for the tenant. This facility controller monitors the power consumption of lighting equipment, air conditioning equipment, etc., and continuously stores the history of the monitored power consumption. Then, based on the stored history of power consumption, the facility controller predicts the future power consumption of each electrical device. Further, based on the prediction of future power consumption, the facility controller calculates the time period during which the power consumption peaks, and creates a discharge plan to discharge power from the power storage unit during the calculated time period. Thereby, it is suppressed that the maximum value of the power consumption exceeds the contract power.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above Patent Document 1, the facility controller predicts the future power consumption of each electrical device based on the stored power consumption history, and calculates the time period during which the power consumption peaks based on the prediction of the predicted future power consumption. However, in the above Patent Document 1, the method for predicting future power consumption is not specifically specified, nor is the method for calculating the time period during which the power consumption peaks specifically specified. Here, even on the same day of the week or the same day of the previous year that are considered to show the same tendency, the time period during which the power consumption peaks may vary. That is, even on days that are considered to show the same tendency, the time period during which the power consumption peaks may be different. However, in the above Patent Document 1, since the method for predicting future power consumption and the method for calculating the time period during which the power consumption peaks are not specified, there may be a problem that the power cannot be appropriately discharged from the power storage unit to the electrical equipment when the peak of power consumption varies daily according to the configuration of the above Patent Document 1.

[0006] The present invention has been made to solve the above problems, and one object of the present invention is to provide a power control system and a power control device capable of appropriately discharging power from a power storage unit to equipment provided in a facility even when the peak of power demand varies daily.

Means for Solving the Problems

[0007] In order to achieve the above object, a power control system according to a first aspect of the present invention is a power control system that controls the power of a facility equipped with devices operated by power supplied from a commercial power source, and includes a power storage unit that discharges power to the devices in the facility, and a control unit that controls the discharge of the power storage unit. The control unit stores the past power demand used in the facility in a storage unit at predetermined time intervals, extracts the peak time periods when the power demand peaks from each of a plurality of days selected based on a predetermined criterion among the past power demands stored in the storage unit, and determines the future timing for discharging power from the power storage unit to the devices based on the extracted plurality of peak time periods.

[0008] In the power control system according to the first aspect of the present invention, as described above, the control unit extracts the peak time zones when the power demand peaks from each of a plurality of days selected based on a predetermined criterion, and based on the plurality of extracted peak time zones, determines the future timing for discharging power from the power storage unit to the device. As a result, since a plurality of peak time zones when the power demand peaks are extracted from a plurality of days selected based on a predetermined criterion, even when there are variations in the power demand on days that are considered to show a similar tendency, power is supplied from the power storage unit to the device in the plurality of peak time zones. As a result, even when the peak of the power demand varies from day to day, power can be appropriately discharged from the power storage unit to the devices provided in the facility.

[0009] In the power control system according to the first aspect, preferably, the control unit extracts the peak time zone when the power demand peaks from the actual values of the past power demand stored in the storage unit. Here, when taking the average value of the past power demand, the characteristics of the original peak of the peak power demand are weakened. For example, when taking the average value when the power demand varies greatly due to different operations even in the same time zone in the facility, the characteristics of the power demand are weakened. Therefore, when determining the timing for discharging power from the power storage unit to the device based on the average value of the power demand, the timing may not be determined appropriately. Therefore, by extracting the peak time zone when the power demand peaks from the actual value of the power demand, the characteristics of the peak are not weakened, so the timing for discharging power from the power storage unit to the device can be determined appropriately.

[0010] In the power control system according to the first aspect, preferably, the control unit extracts peak time zones in which the power demand peaks in each of the morning and afternoon time zones from a plurality of selected days. Here, while the peak of power demand appears in the evening at home and the like, there are cases where the peak of power demand also appears during the morning for facility preparation such as stores. That is, there may be multiple peaks in power demand. Therefore, with the above configuration, when there are peaks in both the morning and afternoon time zones, power can be discharged from the power storage unit to the device in both the morning and afternoon time zones.

[0011] In the power control system according to the first aspect, preferably, the control unit determines the timing so that power is discharged from the power storage unit to the device for a time longer than the peak time zone including the extracted peak time zone. With this configuration, since power is discharged from the power storage unit to the device for a time longer than the peak time zone, even if the peak time zone today and the peak time zone extracted based on the past power demand are shifted, it is possible to suppress the power demand of the facility from exceeding the contract power.

[0012] In the power control system according to the first aspect, preferably, the control unit extracts peak time zones in which the power demand peaks from at least two of the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded among the past 365 days as a plurality of days. With this configuration, even when there are variations in power demand despite being the same day of the week and the like, power is supplied from the power storage unit to the device in a plurality of peak time zones, so that power can be appropriately discharged from the power storage unit to the devices provided in the facility. Also, by considering the power demand on the day when the maximum power demand was recorded among the past 365 days, it is possible to determine the timing for discharging power from the power storage unit to the device corresponding to the worst value of power demand. That is, it is possible to suppress the power demand from reaching the worst value.

[0013] In this case, preferably, the control unit sets priorities in advance for the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded within the past 365 days, and when the discharge amount of power from the power storage unit to the device at the determined timing exceeds the capacity of the power storage unit, it corrects the future timing of discharging power from the power storage unit to the device according to the priority. With this configuration, even when the discharge amount of power from the power storage unit to the device exceeds the capacity of the power storage unit, power is discharged from the power storage unit to the device according to the priority, so the timing of discharging from the power storage unit can be determined more appropriately.

[0014] In the power control system according to the first aspect, preferably, the device includes a cooling device and a showcase that performs a defrosting operation, and the control unit stores in the storage unit the time period during which the past showcase performs the defrosting operation, and based on the time period during which the defrosting operation is performed and stored in the storage unit, in addition to the plurality of peak time periods extracted, it determines the future timing of discharging power from the power storage unit to the device. With this configuration, unlike the case of discharging from the power storage unit when the power consumption of the facility is monitored and the power consumption increases by feedback control, the timing of discharging from the power storage unit is determined based on the time period during which the defrosting operation is performed and stored in the storage unit in advance, so even when the power consumption increases rapidly, it is possible to suppress the power demand from exceeding the contract power.

[0015] In the power control system according to the first aspect, preferably, the control unit includes a clock circuit having a clock function, acquires the time deviation of the clock circuit, and controls to discharge power from the power storage unit to the device at the timing when the time is shifted by the minutes of the acquired time deviation. With this configuration, even when the clock circuit of the control unit has a time deviation, power can be discharged from the power storage unit to the device at an appropriate timing.

[0016] The power control device according to the second aspect of the present invention is a power control device that controls the power of a facility equipped with equipment operated by power supplied from a commercial power source, and includes a control unit that controls the discharge of a power storage unit that discharges power to the equipment in the facility. The control unit stores the past power demand used in the facility at predetermined time intervals in a storage unit, and extracts peak time zones when the power demand peaks from each of a plurality of days selected based on a predetermined criterion among the past power demands stored in the storage unit, and determines the future timing for discharging power from the power storage unit to the equipment based on the extracted plurality of peak time zones.

[0017] In the power control device according to the second aspect of the present invention, as described above, the control unit stores the past power demand used in the facility at predetermined time intervals in a storage unit, and extracts a plurality of peak time zones when the power demand peaks from a plurality of days selected based on a plurality of criteria among the past power demands stored in the storage unit. As a result, a plurality of peak time zones when the power demand peaks are extracted from a plurality of days selected based on a predetermined criterion, so that even when there are variations in the power demand, such as on days that are considered to show a similar trend, power is supplied from the power storage unit to the equipment in the plurality of peak time zones. As a result, even when the peak of the power demand varies from day to day, a power control device capable of appropriately discharging power from the power storage unit to the equipment provided in the facility can be provided.

Effect of the Invention

[0018] According to the present invention, as described above, even when the peak of the power demand varies from day to day, power can be appropriately discharged from the power storage unit to the equipment provided in the facility.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Mode for Carrying Out the Invention

[0020] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

[0021] [First Embodiment] With reference to FIG. 1, the configuration of the power control system 100 according to the first embodiment will be described. The power control system 100 is used, for example, in a store 1 such as a convenience store. The power control system 100 is used to avoid the power demand of the store 1 exceeding the contract power that the store 1 has contracted with the power company. Also, the contract power is the largest value among the maximum power demands (demand values) of each month in the past year. Further, the maximum power demand is the power used in the store 1 measured every 30 minutes, and is the largest value among them in a month. Note that the store 1 is an example of the "facility" in the claims.

[0022] The store 1 where the power control system 100 is arranged will be described. In store 1, there are arranged a device 2 operated by power supplied from a commercial power supply 500, a power measurement unit 3, and a power generation unit 4. The plurality of devices 2 include, for example, a showcase 2a for arranging goods, a beverage manufacturing device 2b, a cooking facility 2c, an air conditioner 2d, and lighting 2e. The showcase 2a includes a cooling device. Further, the showcase 2a performs a cooling operation, a heating operation, a defrosting operation, and a stop as operation modes. The showcase 2a includes a refrigeration cycle in which a refrigerant (not shown) circulates. Also, the showcase 2a is a separate-type showcase in which a showcase outdoor unit having a compressor mainly for compressing and sending out the refrigerant, which is a part of the refrigeration cycle, is separated, and a built-in type showcase having a built-in compressor. The showcase 2a is cooled by the latent heat of evaporation of the refrigerant and heated by using a heater or the latent heat of condensation of the refrigerant.

[0023] The beverage manufacturing device 2b is a device for manufacturing beverages including coffee and juice. The cooking facility 2c is, for example, a fryer for cooking fried foods.

[0024] The air conditioner 2d is an air conditioning system for performing cooling and heating in store 1. The lighting 2e is provided in store 1. The lighting 2e includes, for example, LEDs (Light Emitting Diodes).

[0025] The power measurement unit 3 is connected to the device 2, and the control unit 10 of the power control system 100 can acquire information on the power demand of the device 2 from the power measurement unit 3.

[0026] The power generation unit 4 includes, for example, a solar panel 4a and a power conversion unit 4b. The solar panel 4a includes a plurality of cells. The power conversion unit 4b converts the power generated by the solar panel 4a into power that can be used by the device 2 in store 1 or power that can be stored in the power storage unit 30 of the power control system 100.

[0027] The power control system 100 includes a control unit 10, a storage unit 20, and a power storage unit 30. The power storage unit 30 discharges power to the devices 2 in the store 1. The power storage unit 30 includes a storage battery 31 and a power conversion unit 32. The storage battery 31 is, for example, a lead-acid battery or a lithium-ion battery. Also, the capacity of the storage battery 31 is a relatively small capacity of about 10 kWh to 20 kWh. For example, there is a storage battery 31 with a capacity of 15 kWh and a dischargeable power amount of 2.25 kWh (4.5 kW) for 30 minutes. The power conversion unit 32 converts the power of the commercial power supply 500 or the power generated by the power generation unit 4 into power that can be stored in the storage battery 31. Note that the control unit 10 and the storage unit 20 are an example of the "power control device" in the claims.

[0028] The control unit 10 includes a processor and controls the entire power control system 100. The storage unit 20 includes a non-volatile memory, a hard disk, etc., and stores various information such as a program for controlling the entire power control system 100.

[0029] (Operation of the power control system) Next, the operation of the power control system 100 (method for controlling the power of the store 1) will be described. As shown in FIG. 2, in step S1, in the first embodiment, the control unit 10 stores the past power consumption (power demand) used in the store 1 at predetermined time intervals in the storage unit 20. In FIG. 3, the horizontal axis represents time, and the vertical axis represents the power demand every 30 minutes. As shown in FIG. 3, the control unit 10 acquires the power demand every 30 minutes based on the information regarding the power consumption of the device 2 obtained from the power measurement unit 3. Note that the store 1 is equipped with a power generation unit 4, and the power demand in FIG. 3 represents the difference between the actual power consumption used in the store 1 and the power generated by the power generation unit 4. Here, in a general household, the power demand tends to increase in the afternoon (evening). On the other hand, in the store 1, due to the increase in the number of customers during business preparation and in the morning during commuting, the power demand may also increase in the morning. Also, in the store 1, the power demand tends to vary daily. Note that the dashed line shown in FIG. 3 represents the contract power. The control unit 10 acquires the past power demand for at least one year and stores it in the storage unit 20.

[0030] As shown in FIG. 2, in step S2, in the first embodiment, the control unit 10 extracts, from each of a plurality of days selected based on a predetermined criterion among the past power demands stored in the storage unit 20, the peak time zone when the power demand peaks. Specifically, the control unit 10 extracts the peak time zone when the power demand peaks from at least two of the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded among the past 365 days as the plurality of days. In the first embodiment, the control unit 10 extracts the peak time zone when the power demand peaks from all of the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded among the past 365 days. Further, the peak of the power demand means the maximum value of the power demand.

[0031] Also, in the first embodiment, the control unit 10 extracts the peak time zone when the power demand peaks from the past power demand values themselves stored in the storage unit 20. That is, the control unit 10 does not calculate the average value or median value of the power demands in the same time zone of a plurality of days, but extracts the peak time zone when the power demand peaks from the values measured by the power measurement unit 3 themselves. Further, when there are a plurality of time zones where the peak values of the power demand are the same, the control unit 10 extracts all of these time zones as the peak time zones. Also, in the first embodiment, the control unit 10 extracts the peak time zone when the power demand peaks in each of the morning and afternoon time zones from the selected plurality of days.

[0032] The peak time zones extracted as described above are shown in FIG. 4. In FIG. 4, the horizontal axis represents time, and the vertical axis represents power demand. Also, FIG. 4 shows the power demand for a certain day. The power demand is represented by the hatched bar graph. As shown in FIG. 4, the maximum power demand is extracted at 4:00 am, 5:00 pm, and 6:00 pm. The reason why there are two maximum power demands in the afternoon is that the power demands at 5:00 pm and 6:00 pm are the same. Also, as described above, the peak time zones when the power demand peaks are extracted from each of the four days: the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded among the past 365 days. Also, the peak time zones when the power demand peaks are extracted for each of the morning and afternoon time zones of each of the four days. For example, a total of 8 peak time zones are extracted from the morning and afternoon of the above four days. In FIG. 4, since two peak time zones are extracted in the afternoon, in the case including the case like FIG. 4, more than 8 peak time zones are extracted. Also, the peak of the power demand means the maximum value of the power demand.

[0033] As shown in FIG. 2, in step S3 of the first embodiment, the control unit 10 determines the timing for discharging power from the power storage unit 30 to the device 2 based on the plurality of peak time zones extracted. Specifically, the control unit 10 determines the timing so as to discharge power from the power storage unit 30 to the device 2 for a time longer than the peak time zone including the extracted peak time zone. For example, the control unit 10 determines the timing so as to discharge power from the power storage unit 30 to the device 2 including 30 minutes before and after the extracted peak time zone. Note that, as described above, FIG. 4 shows the power demand for one day. For example, if 8 different peak time zones are extracted, power is discharged from the power storage unit 30 to the device 2 in the 8 peak time zones. Also, since the peak time zones extracted from different days may be the same time zone, in actuality, even if 8 peak time zones are extracted, the number of peak time zones in which power is discharged may be less than 8. Hereinafter, assuming that as a result of extracting peak time zones in each of the morning and afternoon time zones of each of the above 4 days, 3 time zones as shown in FIG. 4 are extracted as the peak time zones in which power is discharged, an explanation will be given. In the example shown in FIG. 4, the morning peak time zone is 4:00 am (actually, the time zone from 4:00 pm to 4:30 pm), and the timing is determined so that power is discharged from the power storage unit 30 to the device 2 between 3:30 am and 5:00 am. Also, the afternoon peak time zones are 5:00 pm (the time zone from 5:00 pm to 5:30 pm) and 6:00 pm (the time zone from 6:00 pm to 6:30 pm), and the timing is determined so that power is discharged from the power storage unit 30 to the device 2 between 4:30 pm and 7:00 pm. In FIG. 4, the timing of discharging from the storage battery 31 is represented by hatching.

[0034] Also, in the first embodiment, the control unit 10 sets priorities in advance for the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded within the past 365 days. The priorities are set in advance by the user, for example. Then, in step S4 shown in FIG. 2, the control unit 10 determines whether the amount of power discharged from the power storage unit 30 to the device 2 at the determined timing exceeds the capacity of the power storage unit 30. If the result in step S4 is no, the control unit 10 discharges power from the power storage unit 30 to the device 2 at the determined timing in step S6.

[0035] As described above, for example, the capacity of the storage battery 31 is 15 kWh, and there is a storage battery 31 with a dischargeable power amount of 2.25 kWh (4.5 kW) in 30 minutes. In FIG. 4, the dischargeable power amount of such a storage battery 31 in 30 minutes is indicated by a dashed line. In the example shown in FIG. 4, in the morning, the timing is determined such that power is discharged from the power storage unit 30 to the device 2 for a total of 1 hour and 30 minutes from 3:30 am to 5:00 am. The total discharge amount discharged in 1 hour and 30 minutes is 2.25 kWh × 3 = 6.75 kWh, which is within the capacity of 15 kWh of the storage battery 31, so it is possible to discharge between 3:30 am and 4:30 am.

[0036] Note that the store 1 of the first embodiment is equipped with a power generation unit 4. In FIG. 4, the difference (surplus power) between the power used by the device 2 from the power generated by the power generation unit 4 is represented by a white bar graph. The power generated by the power generation unit 4 is used by the device 2, and thus not consumed from the commercial power supply 500. Therefore, in FIG. 4, it is described as a negative value. In the example shown in FIG. 4, while discharging from the power storage unit 30 between 3:30 am and 5:00 am, thereafter, the power storage unit 30 is charged by the power generated by the power generation unit 4. For this reason, at 4:30 pm, which is the start time of discharging in the afternoon, the power storage unit 30 is fully charged. And the total discharge amount discharged for a total of 2 hours and 30 minutes between 4:30 pm and 7:00 pm in the afternoon is 2.25 kWh × 5 = 11.25 kWh, which is within the capacity of 15 kWh of the storage battery 31. Therefore, it is possible to discharge for a total of 2 hours and 30 minutes between 4:30 pm and 7:00 pm in the afternoon.

[0037] Also, when the answer is yes in step S4, the control unit 10, in step S5, corrects the future timing of discharging power from the power storage unit 30 to the device 2 according to the priority. For example, assume that due to factors such as bad weather, the storage battery 31 is not fully charged at 4:30 pm and cannot be discharged for all the time from 4:30 pm to 7:00 pm in the afternoon. Note that the control unit 10 grasps the charge amount of the storage battery 31. And as described above, the control unit 10 corrects the future timing of discharging power from the power storage unit 30 to the device 2 according to the priority. For example, assume that the priority of the day when the peak time zone at 5:00 pm is extracted is lower than the priority of the day when the peak time zone at 6:00 pm is extracted. In this case, the control unit 10 corrects the discharging timing from the power storage unit 30 so as to discharge between 5:30 pm and 7:00 pm, which is 30 minutes before and after the peak time zone at 6:00 pm. Thereafter, in step S6, power is discharged from the power storage unit 30 to the device 2 at the determined timing.

[0038] Note that the operations of steps S1 to S6 above are repeated daily, the past power demands are stored daily, and the discharging timing from the power storage unit 30 today is determined daily.

[0039] (Effect of the First Embodiment) In the first embodiment, the following effects can be obtained.

[0040] In the first embodiment, as described above, the control unit 10 extracts a peak time zone in which the power demand peaks from each of a plurality of days selected based on a predetermined criterion, and based on the plurality of extracted peak time zones, determines the timing for discharging power from the power storage unit 30 to the device 2 in the future. As a result, since a plurality of peak time zones in which the power demand peaks are extracted from a plurality of days selected based on a predetermined criterion, even when there are variations in the power demand even on days that are considered to show a similar trend, power is supplied from the power storage unit 30 to the device 2 in the plurality of peak time zones. As a result, even when the peak of the power demand varies from day to day, power can be appropriately discharged from the power storage unit 30 to the device 2 provided in the store 1.

[0041] In the first embodiment, as described above, the control unit 10 extracts a peak time zone in which the power demand peaks from the values of the past power demand stored in the storage unit 20 itself. Here, when taking the average value of the past power demand, the characteristics of the original peak of the peak power demand are weakened. For example, if the average value is taken when the power demand varies greatly due to different operations even in the same time zone in the store 1, the characteristics of the power demand are weakened. Therefore, when determining the timing for discharging power from the power storage unit 30 to the device 2 based on the average value of the power demand, the timing may not be determined appropriately. Therefore, by extracting the peak time zone in which the power demand peaks from the value of the power demand itself, the characteristics of the peak are not weakened, so that the timing for discharging power from the power storage unit 30 to the device 2 can be determined appropriately.

[0042] In the first embodiment, as described above, the control unit 10 extracts peak time zones in which the power demand peaks in each of the morning and afternoon time zones from the selected plurality of days. Here, while the peak of power demand appears in the evening at home or the like, there are cases where the peak of power demand also appears during the morning for the preparation of business at facilities such as Store 1. That is, there may be multiple peaks in the power demand. Therefore, by configuring as described above, when there are peaks in each of the morning and afternoon time zones, power can be appropriately discharged from the power storage unit 30 to the device 2 in both the morning and afternoon time zones.

[0043] In the first embodiment, as described above, the control unit 10 determines the timing so as to discharge power from the power storage unit 30 to the device 2 for a time longer than the peak time zone including the extracted peak time zone. As a result, since power is discharged from the power storage unit 30 to the device 2 for a time longer than the peak time zone, even if the peak time zone today and the peak time zone extracted based on the past power demand are shifted, it is possible to suppress the power demand of Store 1 from exceeding the contract power.

[0044] In the first embodiment, as described above, the control unit 10 extracts peak time zones in which the power demand peaks from at least two of the plurality of days, namely, the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded among the past 365 days. Thereby, even when there are variations in the power demand despite being the same day of the week or the like, power is supplied from the power storage unit 30 to the device 2 in a plurality of peak time zones, so that power can be appropriately discharged from the power storage unit 30 to the device 2 provided in Store 1. Also, by considering the power demand on the day on which the maximum power demand was recorded among the past 365 days, it is possible to determine the timing for discharging power from the power storage unit 30 to the device 2 corresponding to the worst value of the power demand. That is, it is possible to suppress the power demand from reaching the worst value.

[0045] In the first embodiment, as described above, the control unit 10 sets priorities in advance for the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded within the past 365 days. When the amount of power discharged from the power storage unit 30 to the device 2 at the determined timing exceeds the capacity of the power storage unit 30, the future timing of discharging power from the power storage unit 30 to the device 2 is corrected according to the priority. Thereby, even when the amount of power discharged from the power storage unit 30 to the device 2 exceeds the capacity of the power storage unit 30, power is discharged from the power storage unit 30 to the device 2 according to the priority, so that the timing of discharging from the power storage unit 30 can be determined more appropriately.

[0046] [Second Embodiment] The configuration of the power control system 200 according to the second embodiment will be described.

[0047] As shown in FIG. 1, in the power control system 200, the control unit 210 stores in the storage unit 20 the time zone during which the defrosting operation of the past showcase 2a is performed. Then, in addition to the plurality of peak time zones extracted, the control unit 210 determines the future timing of discharging power from the power storage unit 30 to the device based on the time zone during which the defrosting operation stored in the storage unit 20 is performed. For example, in the example shown in FIG. 5, 2:00 PM is stored in the storage unit 20 as the time zone during which the defrosting operation of the past showcase 2a is performed, and the control unit 10 controls the battery 31 to discharge from 1:30 PM to 2:30 PM including 2:00 PM. Specifically, as shown in FIG. 6, in the defrosting operation of the showcase 2a, the defrosting operation is started by turning on the heater provided in the showcase 2a. After that, after the heater is turned off, a cooling operation (cooling recovery operation) is performed to lower the temperature inside the warmed showcase 2a. Note that the power consumption of this cooling recovery operation is larger than the power consumption of the defrosting operation. The control unit 210 controls the power storage unit 30 so that discharging starts from the power storage unit 30 before the start time of the defrosting operation of the showcase 2a. Also, the control unit 210 controls the power storage unit 30 so that discharging starts from the power storage unit 30 before the start time of the cooling recovery operation of the showcase 2a (for example, 1:30 PM). Further, the control unit 210 makes the discharge amount during the cooling recovery operation larger than the discharge amount during the defrosting operation. Also, the control unit 210 controls the battery 31 to discharge from the power storage unit 30 until the time when the cooling recovery operation ends or a time in the vicinity thereof (for example, 2:30 PM). Note that in the example shown in FIG. 5, the defrosting operation of the showcase 2a is performed once a day, but the defrosting operation may be performed multiple times a day. In this case, the discharge from the power storage unit 30 for the defrosting operation is performed multiple times a day. Note that the control unit 210 is an example of the "power control device" in the claims.

[0048] (Effect of the Second Embodiment) In the second embodiment, the following effects can be obtained.

[0049] In the second embodiment, as described above, the control unit 210 stores in the storage unit 20 the time period during which the defrosting operation of the past showcase 2a is performed, and based on the time period during which the defrosting operation stored in the storage unit 20 is performed, in addition to the plurality of peak time periods extracted, determines the future timing of discharging power from the power storage unit 30 to the device 2. As a result, unlike the case where power is discharged from the power storage unit 30 when the power consumption of the store 1 is monitored and the power consumption increases due to feedback control, the timing of discharging from the power storage unit 30 is determined based on the time period during which the defrosting operation stored in the storage unit 20 in advance, so that even when the power consumption increases rapidly, it is possible to suppress the power demand from exceeding the contract power.

[0050] [Third Embodiment] The configuration of the power control system 300 according to the third embodiment will be described.

[0051] As shown in FIG. 7, the control unit 310 includes a clock circuit 311 having a clock function. Then, the control unit 310 acquires the time deviation of the clock circuit 311, and controls to discharge power from the power storage unit 30 to the device 2 at the timing when the time is shifted by the minute of the acquired time deviation. Specifically, the time deviation of the clock circuit 311 is acquired by the following measure 1 or measure 2. Note that the control unit 310 is an example of the "power control device" in the claims.

[0052] (Measure 1) The clock circuit 311 is, for example, an RTC (Real Time Clock), which is an IC circuit having a clock function. Also, the power control system 300 is not connected to the network, and the clock circuit 311 cannot correct the time based on information from a time server connected via the network. Here, in the clock circuit 311, the maximum value of the time error range is determined in advance according to the device specifications of the clock circuit 311. Then, the control unit 310 acquires the time deviation of the clock circuit 311 based on the elapsed time since the clock circuit 311 was reset (the time when the time deviation of the clock circuit 311 is zero). Also, the reset time is stored in the storage unit 20. For example, assume that the maximum value of the error range is X seconds per day. The control unit 310 obtains the error range per hour by dividing X seconds by 24. Then, it calculates the difference between the current time and the reset time, and multiplies the calculated difference by the error range per hour to obtain the time deviation. As an example, assume that the maximum error is 48 seconds per day. Then, the control unit 310 obtains 2 seconds, which is the error range per hour, by dividing 48 seconds by 24. Assume that 14 hours have elapsed since the current time (for example, 4:00 p.m.) was reset (for example, 2:00 a.m.). The control unit 310 multiplies 2 seconds, which is the error range per hour, by 14 hours, and obtains that the current time deviation is 28 seconds. Also, assume that the scheduled start time of discharging from the power storage unit 30 is 4:30 p.m. In this case, the control unit 310 controls to start discharging from the power storage unit 30 at 4:29:32 p.m., which is 28 seconds before 4:30 p.m.

[0053] (Measure 2) The clock circuit 311 is, for example, an RTC (Real-Time Clock), which is an IC circuit having a clock function. Further, the power control system 300 is connected to a network, and the clock circuit 311 can correct the time based on information from a time server connected via the network. Specifically, when performing time correction based on information from the time server, the control unit 310 stores the value of the time deviation (the difference between the time of the RTC and the time of the time server) and the correction date and time in the storage unit 20. Further, the storage unit 20 stores the values of the time deviations during a plurality of past time corrections. Then, the control unit 310 calculates, for example, the time deviation per 30 minutes based on the maximum number of seconds among the values of the time deviations for the most recent 10 times stored in the storage unit 20. Then, the control unit 310 calculates the magnitude of the current time deviation (hereinafter referred to as the time deviation correction value) based on the time deviation per 30 minutes and the elapsed time from the previous correction date and time to the present. After that, the control unit 310 performs the control of steps S3 to S6 with the time before the calculated time deviation correction value from the time of the extracted peak time zone as the time of the peak time zone.

[0054] (Effects of the Third Embodiment) In the third embodiment, the following effects can be obtained.

[0055] In the third embodiment, as described above, the control unit 310 includes the clock circuit 311 having a clock function, acquires the time deviation of the clock circuit 311, and controls to discharge power from the power storage unit 30 to the device 2 at the timing when the time is shifted by the acquired time deviation. Thereby, even when the clock circuit 311 of the control unit 10 has a time deviation, power can be discharged from the power storage unit 30 to the device 2 at an appropriate timing.

[0056] [Modification Example] It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the description of the above-described embodiments, and further includes all changes (modification examples) within the meaning and scope equivalent to the scope of claims.

[0057] For example, in the first to third embodiments described above, an example where the power control system controls the power (power storage unit) of a store has been shown, but the present invention is not limited to this. In the present invention, the power control system may control the power (power storage unit) of facilities such as factories other than stores.

[0058] Also, in the first to third embodiments described above, an example where the control unit extracts the peak time zone from the actual values of the past power demands stored in the storage unit has been shown, but the present invention is not limited to this. In the present invention, the control unit may average the values of the past power demands for a plurality of days and extract the peak time zone when the power demand peaks from the averaged values.

[0059] Also, in the first to third embodiments described above, an example where the control unit extracts the peak time zone in each of the morning and afternoon time zones has been shown, but the present invention is not limited to this. In the present invention, the control unit may extract only one peak time zone of the maximum power demand in a day. That is, one peak time zone may be extracted from each of the same day of the previous day or the same day of the previous week.

[0060] Also, in the first to third embodiments described above, an example where the control unit determines the timing to discharge power from the power storage unit to the device including 30 minutes before and after the extracted peak time zone has been shown, but the present invention is not limited to this. In the present invention, the control unit may determine the timing to discharge power from the power storage unit including a time longer than 30 minutes or shorter than 30 minutes before and after the extracted peak time zone. Also, when the error of the extracted peak time zone is small, etc., the control unit may determine the timing to discharge power from the power storage unit to the device during the same time as the extracted peak time zone.

[0061] In addition, in the first to third embodiments described above, an example was shown in which the control unit extracts peak time zones from all of the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded within the past 365 days. However, the present invention is not limited to this. In the present invention, the control unit may extract peak time zones from two or three of the previous day, the same day of the week as today in the previous week, the same day of last year, and the day on which the maximum power demand was recorded within the past 365 days.

[0062] In addition, in the first to third embodiments described above, an example was shown in which when the discharge amount of discharging power from the power storage unit to the device at the determined timing exceeds the capacity of the power storage unit, the future timing of discharging power from the power storage unit to the device is corrected according to the priority. However, the present invention is not limited to this. In the present invention, when the discharge amount of discharging power from the power storage unit to the device at the determined timing exceeds the capacity of the power storage unit, control such as stopping the store's devices may be performed without correcting the timing of discharging.

[0063] In addition, in the second embodiment described above, an example was shown in which the control unit determines the future timing of discharging power from the power storage unit to the device based on the time zones for performing the defrosting operation stored in the storage unit in addition to the plurality of peak time zones extracted. However, the present invention is not limited to this. In the present invention, the control unit may accept a selection as to whether to discharge power during the time zone when the user performs the defrosting operation.

[0064] In addition, in the third embodiment described above, an example was shown in which the control unit acquires the time deviation of the clock circuit by the above-described measure 1 or measure 2. However, the present invention is not limited to this. For example, a plurality of showcases with a clock function are arranged in the store, the control unit acquires time data from the plurality of showcases, and calculates the difference in time between the most advanced time data among the acquired time data and the clock circuit. Then, the control unit may perform the control of steps S3 to S6 shown in FIG. 2 with the previous time as the time of the peak time zone by the amount of the calculated difference.

[0065] In addition, in the first to third embodiments described above, an example in which a storage unit that stores past power demands is provided in the power control system has been shown, but the present invention is not limited to this. For example, past power demands may be stored in a storage unit (such as a cloud) provided outside the power control system and connected via a network.

Explanation of Reference Numerals

[0066] 1 Store (Facility) 2 Equipment 2a Showcase 10, 210, 310 Control Unit (Power Control Device) 20 Storage Unit (Power Control Device) 30 Power Storage Unit 100, 200, 300 Power Control System 311 Clock Circuit 500 Commercial Power Supply

Claims

1. A power control system for controlling the power of a facility equipped with equipment operated by power supplied from a commercial power source, comprising: a power storage unit that discharges power to the equipment in the facility; a control unit that controls the discharge of the power storage unit; and the control unit: stores, in a storage unit, the past power demand used in the facility at predetermined time intervals; extracts, from among the past power demands stored in the storage unit, peak time zones when the power demand peaks for each of a plurality of days selected based on a predetermined criterion; A power control system that determines future timings for discharging power from the power storage unit to the equipment based on the extracted plurality of peak time zones.

2. The power control system according to claim 1, wherein the control unit extracts the peak time zone when the power demand peaks from the values of the past power demands stored in the storage unit itself.

3. The power control system according to claim 1, wherein the control unit extracts peak time zones when the power demand peaks in each of the morning and afternoon time zones from among the selected plurality of days.

4. The power control system according to claim 1, wherein the control unit determines timings to discharge power from the power storage unit to the equipment for a time longer than the peak time zone including the extracted peak time zone.

5. The power control system according to claim 1, wherein the control unit extracts peak time zones when the power demand peaks from at least two of the previous day, the same day of this week last week, the same day of last year, and the day with the highest recorded power demand among the past 365 days as the plurality of days.

6. The control unit: pre - sets priorities for the previous day, the same day of this week last week, the same day of last year, and the day with the highest recorded power demand among the past 365 days; When the discharge amount of discharging power from the power storage unit to the equipment at the determined timing exceeds the capacity of the power storage unit, the power control system according to claim 5 corrects the future timing of discharging power from the power storage unit to the equipment according to the priority.

7. The equipment includes a showcase that has a cooling device and performs a defrosting operation, the control unit: stores, in the storage unit, the time zone for performing the defrosting operation of the past showcase. The power control system according to claim 1, wherein in addition to the plurality of extracted peak time zones, future timings for discharging power from the power storage unit to the device are determined based on the time zone for performing the defrosting operation stored in the storage unit.

8. The control unit includes a clock circuit having a clock function, acquires a time deviation of the clock circuit, and controls to discharge power from the power storage unit to the device at a timing obtained by shifting the time by the minutes of the acquired time deviation. The power control system according to claim 1.

9. A power control device that controls the power of a facility provided with a device operated by power supplied from a commercial power source, comprising: a control unit that controls the discharge of a power storage unit that discharges power to the device in the facility; The control unit stores, in a storage unit, the past power demand used in the facility at predetermined time intervals, extracts, from each of a plurality of days selected based on a predetermined criterion among the past power demands stored in the storage unit, peak time zones in which the power demand peaks, and determines future timings for discharging power from the power storage unit to the device based on the plurality of extracted peak time zones. A power control device.

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