Power demand control device, power demand control program

Abstract

To reduce a burden on a user by load suppression by efficiently using a storage battery, and to efficiently suppress an excess of target power.SOLUTION: Conventionally, there is no configuration in which a power supply mode is selected based on difference between a daily demand excess amount and a power storage capacity while a power prediction value with load suppression and a power prediction value with no load suppression are divided. Thus, it is possible to clearly determine whether or not the load suppression is necessary, and it also becomes possible to preserve an amount of power storage of a storage battery 32.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power demand control device and a power demand control program that have at least system power from a system and battery power from a storage battery as power supply sources for power consumed by load equipment and selects the power supply sources. [Background technology]

[0002] In recent years, power systems that combine power received from the grid and power discharged from storage batteries have been applied as power supply sources for consumption by load equipment. In some power systems, power generated by solar power generation (a typical example of renewable energy) is also added to the power supply sources.

[0003] Incidentally, there are cases where the power supplied from the grid is limited, referred to as contracted power or target power (hereinafter referred to as target power).

[0004] In demand control that controls so as not to exceed a target power, it is necessary to perform load suppression or battery discharge as an operation to suppress the excess.

[0005] Patent Document 1 describes a technology for demand control equipped with a storage battery, which provides multiple modes that can be switched externally, defines an arithmetic formula for calculating charge / discharge power for each mode, switches the arithmetic formula depending on the mode, calculates the charge / discharge power, and notifies this value to the storage battery equipment.

[0006] In addition, Patent Document 1 describes mode examples such as mode 1 (charge / discharge power = regulated power value), mode 2 (charge / discharge power = regulated power value + load power capacity that can be applied), and mode 3 (charge / discharge power = regulated power value - load power capacity that can be cut off).

[0007] Furthermore, Patent Document 2 describes a technology for demand control using a storage battery, which involves charging the storage battery in advance when a peak is predicted, and changing (raising) the target power (contracted power) in advance if the storage battery cannot cope with the peak even when fully charged, so that the storage battery does not run out of capacity while coping with the peak. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-205454 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-284586 Summary of the Invention [Problem to be solved by the invention]

[0009] However, in conventional technologies such as Patent Document 1, the priority of suppression operations (battery discharge and load suppression) is predetermined or predetermined as an alternative, and depending on the progression of excess, the suppression operations may not function appropriately, resulting in inefficient use of the battery and imposing a burden on users due to load suppression.

[0010] Furthermore, in the prior art such as Patent Document 2, the countermeasures are not combined with other suppression operations such as load suppression, and therefore the storage battery is not used to its full potential. In other words, the countermeasures for when the peak prediction is off are insufficient, and if the load is higher than expected, the storage battery runs out while responding to the peak, or if the load is lower than expected, the storage battery is conserved more than necessary and the target power is updated to be higher, making it impossible to efficiently suppress exceeding the target power.

[0011] The object of the present invention is to provide a power demand control device and a power demand control program that can efficiently utilize storage batteries to reduce the burden on users by suppressing loads and efficiently suppress exceeding target power. [Means for solving the problem]

[0012] A power demand control device according to a first aspect of the present invention is a power demand control device that has at least system power supplied from a system and battery power discharged from a storage battery as sources of power consumed by load equipment, and has a prediction unit that predicts a suppressed power prediction value when the power consumption of the load equipment is suppressed by a predetermined amount or ratio, and a non-suppressed power prediction value when the power consumption of the load equipment is not suppressed, during a predetermined control unit period, and a selection unit that selects a plurality of power supply modes including a discharge priority mode that prioritizes discharging of the storage battery and a load suppression priority mode that prioritizes suppressing power consumption of the load equipment, based on the difference between the suppressed power prediction value and the non-suppressed power prediction value predicted by the prediction unit and a target power during the control unit period that is set as power to be received from the system power.

[0013] A power demand control device according to a second aspect of the present invention is a power demand control device that has at least system power supplied from a system and battery power discharged from a storage battery as sources of power consumed by load equipment, and that has: a prediction unit that divides a predetermined control unit period into a plurality of time zones, and predicts, for each of the divided time zones, a suppressed power prediction value when power consumption of the load equipment is suppressed by a predetermined amount or ratio, and an unsuppressed power prediction value when power consumption of the load equipment is not suppressed; and a selection unit that selects a plurality of power supply modes including a discharge priority mode that prioritizes discharging of the storage battery and a load suppression priority mode that prioritizes suppression of power consumption of the load equipment, based on a comparison result between the storage capacity of the storage battery and a total value obtained by subtracting a target power for the control unit period set as power to be received from the system power from each of the suppressed power prediction value and the unsuppressed power prediction value predicted by the prediction unit.

[0014] In the second invention, if the difference is negative, it is replaced with 0.

[0015] In the first or second invention, the load equipment further includes power generated by renewable energy power generation as a supply source of power consumed by the load equipment, and the power generated by the generated power is subtracted from the suppressed power prediction value and the unsuppressed power prediction value predicted by the prediction unit to obtain a difference from the target power for the control unit period.

[0016] In the first or second invention, the selection conditions of the selection unit include a first condition of whether or not the excess of the unsuppressed power prediction value over the target power is less than an upper threshold value of a storage capacity of the storage battery, a second condition of whether or not the excess of the suppressed power prediction value over the target power is less than a lower threshold value that is lower than the upper threshold value of a storage capacity of the storage battery, and a third condition of whether or not the excess of the suppressed power prediction value over the target power is less than the upper threshold value of a storage capacity of the storage battery, and when the first condition is met, a discharge as the power supply mode is set. The control unit 100 selects a priority mode, and if the first condition is not met and the second condition is met, allocates the load reduction amount over a control unit period, and selects a discharge priority mode as the power supply mode; if the first condition is not met and the second condition is not met and the third condition is met, selects the load reduction priority mode as the power supply mode; if the first condition is not met and the second condition is not met and the third condition is not met, selects the load reduction priority mode as the power supply mode, and resets the target power.

[0017] In the first or second invention, the upper threshold value and the lower threshold value are each a value set with a predetermined safety factor that depends on the prediction accuracy of the prediction unit with respect to the capacity of the storage battery when fully charged.

[0018] In the first or second invention, the control amount of the load reduction in the load reduction priority mode is commanded with a predetermined range, and when the commanded control amount is not a predetermined maximum control amount and when a predetermined condition is met, the control amount of the load reduction is increased in response to the command, with the maximum control amount as a limit, and the surplus power corresponding to the increase is charged to the storage battery.

[0019] A power demand control program according to the present invention is characterized in that it causes a computer to operate as the power demand control device according to the first or second invention.

[0020] According to the first aspect of the present invention, when predicting the power consumption of a load equipment during a predetermined control unit period, the prediction unit predicts a suppressed power prediction value when the power consumption of the load equipment is suppressed by a predetermined amount or ratio, and a non-suppressed power prediction value when the power consumption of the load equipment is not suppressed.

[0021] The selection unit selects a plurality of power supply modes, including a discharge priority mode that prioritizes discharging the storage battery and a load reduction priority mode that prioritizes reducing power consumption by load equipment, based on the difference between the predicted power value with reduction and the predicted power value without reduction predicted by the prediction unit and the target power for a control unit period set as power received from the grid power.

[0022] In a second aspect of the present invention, a predetermined control unit period is divided into a plurality of time slots, and when predicting the power consumed by the load equipment for each of the divided time slots, a suppressed power prediction value when the power consumption of the load equipment is suppressed by a predetermined amount or ratio and an unsuppressed power prediction value when the power consumption of the load equipment is not suppressed are predicted.The predicted values ​​for each divided time slot (suppressed power prediction value and unsuppressed power prediction value) are subtracted from the target power for the control unit period set as the power to be received from the grid power, and the sum of the differences is calculated over the control unit period.The sum is then compared with the storage capacity of the storage battery, and multiple power supply modes are selected, including a discharge-priority mode that prioritizes discharging the storage battery and a load-suppression-priority mode that prioritizes suppressing the power consumption of the load equipment.Note that if the difference is negative, it is preferable to replace it with 0.

[0023] In addition, if the system is further equipped with power generation, the power generated by the power generation unit is subtracted from the predicted power value with suppression and the predicted power value without suppression predicted by the prediction unit to obtain the difference from the target power for the control unit period.

[0024] Examples of selection conditions in the selection section (selection conditions 1 to 4) are shown below.

[0025] (Selection Condition 1) When the excess of the predicted power value without suppression relative to the target power is less than the upper threshold value of the power storage capacity of the storage battery, the discharge-priority mode is selected as the power supply mode.

[0026] (Selection condition 2) If the excess of the predicted power value without suppression over the target power is equal to or greater than the upper threshold value of the storage capacity of the storage battery, and the excess of the predicted power value with suppression over the target power is less than the lower threshold value of the storage capacity of the storage battery, the load suppression amount is distributed over the control unit period, and the discharge priority mode is selected as the power supply mode.

[0027] (Selection condition 3) If the amount by which the predicted power value without suppression exceeds the target power is equal to or greater than the upper threshold value of the storage capacity of the storage battery, and if the amount by which the predicted power value with suppression exceeds the target power is equal to or greater than the lower threshold value of the storage capacity of the storage battery, and if the amount by which the predicted power value with suppression exceeds the target power is less than the upper threshold value of the storage capacity of the storage battery, the load suppression priority mode is selected as the power supply mode, and the storage battery is conserved.

[0028] (Selection condition 4) If the excess of the predicted power value without suppression over the target power is equal to or greater than the upper threshold value of the storage capacity of the storage battery, and if the excess of the predicted power value with suppression over the target power is equal to or greater than the lower threshold value of the storage capacity of the storage battery, and if the excess of the predicted power value with suppression over the target power is equal to or greater than the upper threshold value of the storage capacity of the storage battery, then the load suppression priority mode is selected as the power supply mode, and the target power is reset.

[0029] This allows for efficient use of the storage battery, preventing it from being conserved longer than necessary or from running out during demand control, and efficiently prevents the target power from being exceeded while reducing the burden on users by suppressing the load.

[0030] In addition, when the load reduction priority mode is selected, if the control amount commanded in the load reduction priority mode is not a predetermined maximum control amount and if a predetermined condition is met, the load reduction control amount may be increased in response to the command, with the maximum control amount as the limit, and the surplus power corresponding to the increase may be charged to the storage battery. [Effects of the Invention]

[0031] As described above, the present invention has the effect of reducing the burden on users by suppressing the load and efficiently suppressing the target power from being exceeded by efficiently using the storage battery. [Brief explanation of the drawings]

[0032] [Figure 1]1 is a power wiring diagram showing a customer facility on which power demand control according to an embodiment of the present invention is executed. [Figure 2] 1 is a control block diagram of a power demand control device according to an embodiment of the present invention. [Figure 3] 2 is a functional block diagram in which control by the power demand control device according to the present embodiment is classified by function. FIG. [Figure 4] 1A is a conceptual diagram showing a storage capacity indicator of a storage battery applied to the present embodiment, and FIG. 1B is a flowchart showing a storage battery charge control routine executed during operation of power demand control. [Figure 5] 4 is a flowchart showing the flow of power demand control according to the present embodiment. [Figure 6] This is a detailed flowchart illustrating the processing flow of the flowchart in FIG. 5, visually categorizing it into input values, set values, calculations, and instructions. [Figure 7] 10A and 10B are diagrams showing the power amount characteristics when the discharge priority mode is selected as the demand control according to an example of the present embodiment. [Figure 8] 10A and 10B are diagrams showing power amount characteristics when the load suppression priority mode is selected as demand control according to an example of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0033] 1 shows an example of a power wiring system diagram for supplying power to load equipment 14 provided on a demand side 12 that receives power from a power grid 10. The demand side 12 may be, for example, a large or small factory, a house, a building, etc., but is not particularly limited thereto.

[0034] The demand side 12 is equipped with a main power meter 16, and the input side of the main power meter 16 is wired so that power is supplied from the grid power 10.

[0035] The output side of the main power meter 16 is connected to a power receiving facility 18. The power receiving facility 18 includes, for example, a circuit breaker, a ground fault circuit interrupter, etc., and serves to distribute power to the load facilities 14.

[0036] In the present embodiment, load equipment 14 includes air conditioning equipment, lighting equipment, and the like in a house.

[0037] The load equipment 14 is supplied with power from a power receiving equipment 18 via a power meter 20 and a transformer 22 for the load equipment 14 .

[0038] Furthermore, the demand side 12 of this embodiment has a photovoltaic power generation system (hereinafter, sometimes referred to as PV power generation as necessary) as renewable energy power generation. In this embodiment, in addition to power from the grid power 10 and power discharged from a storage battery 32 (described later), PV power generation is adopted as one of the power supply sources.

[0039] The solar power generation system includes a solar power generation device 24. The solar power generation device 24 receives sunlight and is charged.

[0040] The photovoltaic power generation device 24 is connected to the power receiving equipment 18 via a power conditioner 26, a transformer 28, and a power meter 30 for PV power generation.

[0041] Furthermore, in this embodiment, the demand side 12 includes a storage battery 32. The storage battery 32 is capable of charging and discharging (hereinafter, collectively referred to as "charging and discharging").

[0042] When charging the storage battery 32, power is supplied via a power meter 34 for the storage battery, a transformer 36, and a power conditioner 38. When discharging the storage battery 32, power is supplied to the load equipment 14.

[0043] The storage battery 32 is charged and discharged in response to instructions from a storage battery control device 40.

[0044] The main power meter 16, the power meter 20, the power meter 30, the power meter 34, the power receiving equipment 18, and the storage battery control device 40 are connected to a power demand control device 42. The power demand control device 42 executes charge / discharge control for the load equipment 14 and the storage battery 32, and also monitors the power generation status of the photovoltaic power generation system via the power receiving equipment 18.

[0045] To monitor this power generation state, the power demand control device 42 sets a plurality of power supply modes (whether to prioritize battery discharge or load suppression) that can be executed as an operation to suppress the amount of power that exceeds the target power in demand control that controls so that the target power is not exceeded, and appropriately selects the power supply mode for a specific period based on a comparison of the predicted power values ​​with and without load suppression for a control unit period (for example, 1 day = 24 hours) with the storage capacity of the storage battery.

[0046] (Hardware configuration of power demand control device 42) 2, the power demand control device 42 includes a microcomputer 50. The microcomputer 50 includes a CPU 50A, a RAM 50B, a ROM 50C, an input / output port (I / O) 50D, and a bus 50E such as a data bus or a control bus that connects these. A power supply control program according to this embodiment is stored in the ROM 50C, and the CPU 50A operates in accordance with the power demand control program to execute power demand control for the demand side 12. The power demand control program includes a power storage control program for controlling the storage battery control device 40.

[0047] The I / O 50D is connected to a large-scale storage device (for example, a hard disk) 52. The power supply program may be stored in the large-scale storage device 52, or may be stored in a storage medium such as a USB memory or an SD card (not shown).

[0048] The I / O 50D is also connected to the battery control device 40 via an interface (I / F) 54 and to the power receiving equipment 18 via an I / F 56. The I / O 50D is also connected to the main wattmeter 16, the wattmeter 20 for the load equipment 14, the wattmeter 30 for the solar power generation, and the wattmeter 34 for the battery.

[0049] In order to realize power demand control, it is important to make maximum use of the power stored in the storage battery 32 and to reduce the amount of power purchased from the grid power 10 by setting a target power and managing the amount of stored power in preparation for when the upper limit of the received power is about to be exceeded.

[0050] Therefore, the power demand control device 42 of this embodiment predicts in advance (e.g., the day before) the future (e.g., tomorrow) trends in the consumption of the load equipment 14 and the power generation amount of the solar power generation system, controls the remaining capacity of the storage battery 32, and executes either the discharge priority mode or the load suppression priority mode as power demand control.

[0051] In particular, in this embodiment, the power when the load in the load equipment 14 is not suppressed (power prediction value without load suppression), the power when the load is suppressed (power prediction value with load suppression), and the amount of power generated in the solar power generation system (PV power generation prediction value) are predicted.

[0052] Regarding prediction, for example, when predicting the power value without load curtailment, the power value with load curtailment, and the PV power generation amount for tomorrow (the day of control) on the previous day, the time period is set to be more detailed than the 24-hour unit. In this embodiment, the control unit period for prediction is set to 24 hours starting from the day of control, and the transition of the control unit period is predicted. The control unit period is divided into 30-minute intervals (30 minutes x 48 = 24 hours), for example, and predictions are made for every 48 intervals, and the sum of these values ​​is used.

[0053] Here, high prediction accuracy is preferable, but prediction accuracy may decrease due to various factors, such as a decrease in prediction accuracy when there is little past accumulated data, or a temporary decrease in prediction accuracy due to sudden weather changes.

[0054] Therefore, it is particularly preferable to monitor the prediction accuracy of the amount of PV power generation and set a threshold value according to this prediction accuracy to allow a margin for the amount of power stored in the storage battery 32. A safety factor (safety factor a and safety factor b shown in FIG. 4(A), a>b) is used to set this threshold value.

[0055] As shown in FIG. 4A, the safety factors a and b are coefficients that are uniformly subtracted from the amount of electricity stored when fully charged, and the full charge amount x a is the upper threshold value, and the full charge amount x b is the lower threshold value.

[0056] The safety factors a and b are varied depending on the prediction accuracy, and the higher the prediction accuracy, the closer the safety factors a and b become to "1".

[0057] In this embodiment, the power supply mode is selected based on the prediction results (power prediction value without load curtailment, power prediction value with load curtailment, and PV power generation prediction value) according to the following cases (1) to (4).

[0058] (1) If the excess of power in the predicted power value without suppression relative to the target power is less than the upper threshold value set for the storage battery 32, the discharge priority mode is selected as the power supply mode.

[0059] The reason for this selection is that the excess power can be sufficiently covered by the storage capacity of the storage battery 32, and so the discharge priority mode is selected without comparing it with the predicted value of power with suppression. Note that if the prediction is wrong and the received power is higher than predicted, load suppression may be performed.

[0060] (2) If the excess of the predicted power value without suppression over the target power is equal to or greater than the upper threshold value set for the storage battery 32, and the excess of the predicted power value with suppression over the target power is less than the lower threshold value set for the storage battery, the power is allocated over the control unit period, and the discharge priority mode is selected as the power supply mode.

[0061] The reason for this selection is that the storage capacity of the storage battery 32 may not be able to cover the excess power, and the discharge priority mode or the load reduction priority mode is selected by comparing it with the predicted power reduction value. Note that by prioritizing battery discharge, load reduction may be alleviated, thereby reducing the burden on users.

[0062] (3) If the amount by which the predicted power value without suppression exceeds the target power is equal to or greater than the upper threshold value set for the storage battery 32, and if the amount by which the predicted power value with suppression exceeds the target power is equal to or greater than the lower threshold value set for the storage battery 32, and if the amount by which the predicted power value with suppression exceeds the target power is less than the upper threshold value set for the storage battery, the load suppression priority mode is selected as the power supply mode.

[0063] The reason for this selection is that the storage capacity of the storage battery 32 cannot cover the excess amount, so the storage battery output is conserved and the load reduction priority mode is selected.

[0064] (4) If the amount by which the predicted power value without suppression exceeds the target power is equal to or greater than the upper threshold value set for the storage battery 32, and if the amount by which the predicted power value with suppression exceeds the target power is equal to or greater than the lower threshold value set for the storage battery 32, and if the amount by which the predicted power value with suppression exceeds the target power is equal to or greater than the upper threshold value set for the storage battery 32, the load suppression priority mode is selected as the power supply mode, and the target power is reset as an implementation measure.

[0065] The reason for this selection is that the storage capacity of the storage battery 32 is not sufficient to cover the excess, so the storage battery output is conserved and the load reduction priority mode is selected. However, if this continues, there is a possibility that the storage battery will run out of power, so after selecting the load reduction priority mode, a target power that can be achieved without running out of power is set.

[0066] Fig. 3 is a functional block diagram showing the flow of control for prediction and mode selection based on the prediction results in the power demand control device 42. Note that the blocks in Fig. 3 are classified by function and do not limit the hardware configuration. For example, some or all of the blocks may operate in a so-called software manner based on a control program.

[0067] The external information receiving unit 60 receives external information for power prediction, such as meteorological data including temperature, humidity, and amount of solar radiation.

[0068] The external information received by the external information receiving unit 60 is sent to the power prediction unit 62, which executes power prediction.

[0069] The power prediction unit 62, for example, performs regression analysis using the weather data as an explanatory variable and the prediction result as a response variable to create a regression model (such as an arithmetic expression). Based on this regression model, a PV power generation prediction value PVfi is obtained as a prediction value, and the load in the load equipment 14 on the demand side 12 is set to conditions of no load suppression and with load suppression, and a power prediction value without load suppression (power prediction value Lfi without load suppression) and a power prediction value with load suppression (power prediction value L'fi with load suppression) are obtained.

[0070] The PV power generation amount prediction value PVfi, the power prediction value Lfi without load suppression, and the power prediction value L'fi with load suppression may be directly received as external information.

[0071] Here, variable i indicates each section into which the above-mentioned control unit (24 hours) is divided, and in this embodiment, since each section is 30 minutes, i can take on a value from 1 to 48. In the calculation, variable i is incremented sequentially from 1 to 48 (i←i+1), and data for each of the 48 sections is obtained (the same applies to variable i below). However, the control unit and the number of sections are not limited to the above values.

[0072] The power prediction unit 62 is connected to the PV power generation amount subtraction unit 64. The power prediction unit 62 sends the acquired PV power generation amount predicted value PVfi, the power predicted value without load suppression Lfi, and the power predicted value with load suppression L'fi to the PV power generation amount subtraction unit 64.

[0073] In order to determine the grid power component for the load equipment 14, the PV power generation subtraction unit 64 subtracts the PV power generation prediction value PVfi from the power prediction value without load suppression Lfi and the power prediction value with load suppression L'fi, respectively, to obtain the grid power prediction value Fi without load suppression and the grid power prediction value F'i with load suppression (see equations (1) and (2)).

[0074] Fi = Lfi - PVfi (1) F'i = L'fi - PVfi (2)

[0075] The PV power generation amount subtraction unit 64 is connected to the demand excess amount calculation unit 66. The PV power generation amount subtraction unit 64 sends the grid power prediction value Fi without load suppression and the grid power prediction value F′i with load suppression to the demand excess amount calculation unit 66.

[0076] The demand excess amount calculation unit 66 is connected to a target power storage unit 68. When the demand excess amount calculation unit 66 receives the grid power prediction value Fi without load suppression and the grid power prediction value F'i with load suppression from the PV power generation amount subtraction unit 64, it reads the target power P from the target power storage unit 68 and calculates the difference therebetween, that is, the demand excess amount (demand excess amount Oi without load suppression and demand excess amount O'i with load suppression) obtained by subtracting the target power P from each of the grid power prediction value Fi without load suppression and the grid power prediction value F'i with load suppression (see equations (3) and (4)).

[0077] Oi=Fi-P (3) O'i = F'i - P (4)

[0078] In addition, when the results of formula (3) and (4) are negative (i.e., Fi < P or F’i < P), the negative value is treated as 0. In other words, since the negative value is not an excess amount, the excess amount = 0.

[0079] The demand excess amount calculation unit 66 is connected to the summation unit 70. The demand excess amount calculation unit 66 sends the calculation results of each section from 1 to 48 of the variable i to the summation unit 70.

[0080] In the summation unit 70, the calculation results of each section from 1 to 48 of the variable i are summed to calculate the demand excess amount summation value Oi total without load suppression and the demand excess amount summation value O’i total with load suppression (see formula (5) and formula (6)).

[0081] Oi total = ΣOi (i = 1 to 48) ··· (5) O’i total = ΣO’i (i = 1 to 48) ··· (6)

[0082] The summation unit 70 is connected to the comparison unit 72. The summation unit 70 sends the demand excess amount summation value Oi total without load suppression and the demand excess amount summation value O’i total with load suppression to the comparison unit 72.

[0083] In addition, the comparison unit 72 is connected to the battery capacity storage unit 76 and the safety factor storage unit 78 respectively. According to the input from the summation unit 70, the battery capacity M is read from the battery capacity storage unit 76, and the safety factors a and b are read from the safety factor storage unit 78.

[0084] As shown in FIG. 4(A), the safety factor a is a coefficient for setting the upper threshold value, and the safety factor b is a coefficient for setting the lower threshold value. The safety factors a and b stored in the safety factor storage unit 78 are preferably updated as appropriate by a prediction accuracy monitoring function or the like executed separately.

[0085] The comparison unit 72 appropriately compares the total demand excess amount without load suppression Oi total and the total demand excess amount with load suppression O'i total calculated using equations (5) and (6) with the storage capacity taking into account a safety factor, and sends the comparison result to the power supply mode selection unit 80.

[0086] An example of the comparison and selection made by the comparison unit 72 and the power supply mode selection unit 80 is shown in Table 1.

[0087] [Table 1]

[0088] The power supply mode selection unit 80 is connected to the power supply execution instruction unit 82. The power supply mode selection unit 80 sends the selection result (one of (1) to (4) in Table 1) to the power supply execution instruction unit 82.

[0089] Based on the selection result, the power supply execution instruction unit 82 controls the power receiving equipment 18 and / or the storage battery control device 40 to instruct the execution of the selected power supply mode.

[0090] If the selection result is (4), the target power needs to be changed. Therefore, the power supply execution instruction unit 82 instructs the target power modification unit 84 to modify the target power. Based on the instruction from the power supply execution instruction unit 82, the target power modification unit 84 modifies the target power P stored in the target power storage unit 68.

[0091] The operation of this embodiment will be described below with reference to the flowchart of FIG.

[0092] In step 100, external information (for example, weather data including temperature, humidity, and solar radiation) is accepted, and then the process proceeds to step 102, where power prediction is performed. In this power prediction, a PV power generation prediction value PVfi, a power prediction value without load curtailment Lfi, and a power prediction value with load curtailment L'fi are predicted.

[0093] In the next step 104, the amount of power generation is subtracted to obtain the predicted grid power value Fi without load curtailment and the predicted grid power value F'i with load curtailment, and the process proceeds to step 106. In step 106, the target power P is read out, and the process proceeds to step 108.

[0094] In step 108, the demand excess amount with respect to the target power P (the demand excess amount Oi without load suppression and the demand excess amount O'i with load suppression) is calculated, and the process proceeds to step 110.

[0095] In step 110, the calculation results of the demand excess amount variable i for each section from 1 to 48 are summed to obtain the demand excess amount total without load suppression Oi total and the demand excess amount total with load suppression O'i total, and the process proceeds to step 114.

[0096] In step 114, the battery capacity M is read, then the process proceeds to step 116, where the safety factor a and the safety factor b are read, and the process proceeds to step 118.

[0097] In step 118, the total demand excess amount without load suppression Oi total, the total demand excess amount with load suppression O'i total, and the storage capacity with a safety factor added are compared as appropriate, and the process proceeds to step 120.

[0098] In step 120, a power supply mode is selected based on the comparison result (see Table 1).

[0099] In the next step 122, the power receiving equipment 18 and / or the battery control device 40 are controlled to issue an instruction to execute the selected power supply mode, and the process proceeds to step .

[0100] In step 124, it is determined whether the selection result in step 120 is (4) in Table 1, that is, whether the target power needs to be changed.

[0101] If the determination in step 124 is positive, it is determined that a change in the target power is necessary, and the routine proceeds to step 126, where an instruction to change the target power is issued, and the routine ends. If the determination in step 124 is negative, it is determined that a change in the target power is not necessary, and the routine ends.

[0102] Although the present embodiment does not mention charging of the storage battery 32, as an example, as shown in FIG. 4(B), it is possible to charge the storage battery 32 while power demand control is in operation.

[0103] For example, in the load reduction priority mode, the control amount of the load reduction can receive commands within a predetermined range, and when the load is reduced at a level lower than the maximum level (such as when the load of some devices is reduced), the load reduction is increased with the maximum level (the level when the load of all devices is reduced) as the upper limit, and the power obtained by this increase is used to charge the storage battery 32. This makes it possible to ensure the amount of power stored in the storage battery 32.

[0104] 4(B), in the storage battery charging control routine during operation of power demand control, when the remaining storage capacity SOC of the storage battery 32 is compared with the upper limit threshold (=full charge amount M×a), if SOC<(M×a) (positive determination in step 130) and the load suppression level is not a predetermined maximum level (load suppression level<maximum level) (positive determination in step 132), the storage battery 32 may be charged from the grid power 10 so as not to exceed the target power P (step 134). Note that if a negative determination is made in step 130 or step 132, charging is put on hold (step 136).

[0105] As a more specific example, a case can be considered in which power peaks are predicted in the morning and evening of a day.

[0106] If the command level (load suppression level) of the load suppression control amount in the load suppression priority mode during the morning power peak is not a predetermined maximum level, and if the evening power peak is equal to or greater than a threshold as a predetermined condition, the control amount of the morning load suppression is increased up to the maximum level. This increase can be charged to the storage battery 32 to prepare for the evening power peak.

[0107] The specified condition may not be a simple numerical value such as a threshold value, but may be, for example, weather information from a weather forecasting site predicting a power outage due to severe weather, or advance notice information such as a power outage due to construction work, or other information on increased demand that may indicate an increase in the demand for electricity from the storage battery 32, and the specified condition may be deemed to be met when demand increase information is received. [Example]

[0108] The following describes details of the processing flow using the power demand control device 42 described in the above embodiment (see FIG. 6) and examples thereof (see FIGS. 7 and 8).

[0109] Figure 6 visually explains the processing flowing through the flowchart in Figure 5, categorizing it into input values, set values, calculations, and instructions. As a legend, input values ​​are framed in dotted lines, set values ​​are framed in solid lines, calculations are framed in thick solid lines, and instructions (commands) are framed in double lines.

[0110] The predetermined flow itself is the same as the flowchart in FIG. 5, so a detailed description thereof will be omitted here.

[0111] As can be seen from Figure 6, the configuration in which the predicted power value with load suppression and the predicted power value without load suppression are separated and the power supply mode is selected based on the difference between the respective excess demand amounts and the storage capacity is not seen in the past. This makes it possible to clearly determine whether or not load suppression is necessary, and also makes it possible to conserve the storage capacity of the storage battery 32.

[0112] Fig. 7(A) is a power characteristic diagram showing a situation in which the power supply mode (1) in Table 1 is selected. (1) in Table 1 is the discharge priority mode (1), which is executed when Ototal<storage capacity (safety factor: upper reference level a) is affirmed.

[0113] That is, since the storage capacity of the storage battery 32 is sufficient to cover the excess, the discharge priority mode is selected without comparing with the suppression power predicted value.

[0114] In Fig. 7(A), the power exceeding the target power P can be covered by discharging the power stored in the storage battery 32 with a margin of storage capacity, so the discharge priority mode is executed as demand control without obtaining a power prediction value with load suppression. In this case, load suppression is unnecessary or reduced. Note that load suppression may be activated when the prediction is wrong and the load becomes unexpectedly large.

[0115] Fig. 7(B) is a power characteristic diagram showing a situation in which the power supply mode (2) in Table 1 is selected. (2) in Table 1 is the discharge priority mode (2), which is executed when Oitotal<storage capacity (safety factor: upper reference level a) is not true and O'itotal<storage capacity (safety factor: lower reference level b) is true.

[0116] That is, the storage capacity of the storage battery 32 may not be enough to cover the excess, and the discharge priority mode or the load suppression priority mode is selected by comparing with the suppression power prediction value.

[0117] In FIG. 7(B), the power exceeding the target power P has less storage capacity in the storage battery 32 than in (1) of Table 1, but it is difficult to determine whether it can be covered by discharging. To make this determination, a power supply mode is selected by obtaining a power prediction value with load suppression in addition to a power prediction without load suppression. As for demand control, load suppression is mitigated by executing the discharge priority mode.

[0118] 8(A) is a power characteristic diagram showing a situation in which the power supply mode (3) in Table 1 is selected. (3) in Table 1 is the load suppression priority mode (3), which is executed when Oitotal<storage capacity (safety factor: upper reference level a) is not true, O'itotal<storage capacity (safety factor: lower reference level b) is not true, and O'itotal<storage capacity (safety factor: upper reference level a) is true.

[0119] That is, since the storage capacity of the storage battery 32 cannot cover the excess amount, the storage battery output is conserved and the load reduction priority mode is selected.

[0120] In FIG. 8(A), the load reduction priority mode is executed as demand control for power exceeding the target power P. This load reduction makes it possible to conserve the amount of electricity stored in the storage battery 32. In the case of FIG. 8(A), the excess power cannot be covered by battery discharge alone, but if this is done in conjunction with load reduction, it can be covered without changing the target power. Therefore, a mode that conserves the storage battery and prioritizes load reduction is selected.

[0121] Fig. 8(B) is a power characteristic diagram showing a situation in which the power supply mode (4) in Table 1 is selected. (4) in Table 1 is the load suppression priority mode (4), which is executed when Oitotal<storage capacity (safety factor: upper reference level a) is negated, O'itotal<storage capacity (safety factor: lower reference level b) is negated, and O'itotal<storage capacity (safety factor: upper reference level a) is negated.

[0122] That is, since the storage capacity of the storage battery 32 cannot cover the excess amount, the storage battery output is conserved and the load reduction priority mode is selected. At the same time, if the current mode is left as it is, the target power will be exceeded even if the storage battery is discharged after the load reduction is prioritized. Therefore, the target power is reset so that the storage battery does not run out while the load reduction is prioritized.

[0123] In FIG. 8B, the excess power cannot be supplied by the storage battery, and therefore the amount of stored power in the storage battery 32 may run out, so the load reduction priority mode is executed as demand control.

[0124] Furthermore, it is determined that the target power needs to be changed (mainly increased) so that the storage battery will not run out even if the storage battery is discharged after the load reduction is given priority. [Explanation of symbols]

[0125] 10 Grid power 12 Demand side 14 Load equipment 16 Main power meter 18 Power receiving equipment 20 Power meter 22 Transformer 24 Solar power generation devices (renewable energy generation, secondary electricity) 26 Power conditioner 28 Transformer 30 Power meter 32 Storage battery 34 Power meter 36 Transformer 38 Power Conditioner 40 Battery control device 42 Power demand control device 50 Microcomputer 50A CPU 50B RAM 50C ROM 50D Input / Output Ports (I / O) 50E Bus 52 Mass storage 54 Interface (I / F) 56 Interfaces 60 External Information Reception Department 62 Power prediction unit (prediction unit) 64 PV power generation subtraction section 66 Demand excess calculation unit 68 Target power storage section 70 Addition Section 72 Comparison section 76 Battery capacity memory unit 78 Safety factor storage 80 Power supply mode selection unit (selection unit) 82 Power supply execution instruction unit 84 Target power change unit

Claims

1. A power demand control device including at least grid power supplied from a grid and battery power discharged from a battery as a supply source of power consumed by a load facility, a prediction unit that predicts, during a predetermined control unit period, a predicted power value with suppression when the power consumption of the load equipment is suppressed by a predetermined amount or ratio, and a predicted power value without suppression when the power consumption of the load equipment is not suppressed; a selection unit that selects a plurality of power supply modes including a discharge priority mode that prioritizes discharging the storage battery and a load reduction priority mode that prioritizes reducing power consumption of the load equipment, based on a difference between the with-suppression power prediction value and the without-suppression power prediction value predicted by the prediction unit and a target power for the control unit period that is set as power to be received from the grid power; A power demand control device having the above.

2. A power demand control device including at least grid power supplied from a grid and battery power discharged from a battery as a supply source of power consumed by a load facility, a prediction unit that divides a predetermined control unit period into a plurality of time slots, and predicts, for each of the divided time slots, a predicted power value with suppression when the power consumption of the load equipment is suppressed by a predetermined amount or ratio, and a predicted power value without suppression when the power consumption of the load equipment is not suppressed; a selection unit that selects a plurality of power supply modes including a discharge priority mode that prioritizes discharging the storage battery and a load reduction priority mode that prioritizes reducing power consumption of the load equipment, based on a comparison result between a total value of differences obtained by subtracting a target power for the period of the control unit set as power to be received from the grid power from each of the suppressed power prediction value and the non-suppressed power prediction value predicted by the prediction unit and the power storage capacity of the storage battery, the total value being obtained by subtracting the target power for the period of the control unit set as power to be received from the grid power from each of the suppressed power prediction value and the non-suppressed power prediction value predicted by the prediction unit, and the power storage capacity of the storage battery; A power demand control device having the above.

3. The power demand control device according to claim 2 , wherein if the difference is negative, it is replaced with 0.

4. The power demand control device according to any one of claims 1 to 3, further comprising power generated by renewable energy power generation as a supply source of power consumed by the load equipment, and wherein an amount of power generated by the generated power is subtracted from the suppressed power prediction value and the unsuppressed power prediction value predicted by the prediction unit to obtain a difference from a target power for the control unit period.

5. As a selection condition of the selection unit, a first condition whether an excess of the unconstrained power prediction value relative to the target power is less than an upper threshold value of a power storage capacity of the storage battery; a second condition whether the excess of the suppression predicted power value relative to the target power is less than a lower threshold value of the power storage capacity of the storage battery that is lower than the upper threshold value; and setting a third condition that indicates whether or not the excess of the suppression predicted power value relative to the target power is less than the upper threshold value of the power storage capacity of the storage battery; If the first condition is met, a discharge priority mode is selected as the power supply mode; If the first condition is not satisfied and the second condition is satisfied, the load suppression amount is distributed over a control unit period, and a discharge priority mode is selected as the power supply mode; If the first condition is not satisfied, the second condition is not satisfied, and the third condition is satisfied, a load reduction priority mode is selected as the power supply mode; If the first condition is not satisfied, the second condition is not satisfied, and the third condition is not satisfied, a load reduction priority mode is selected as the power supply mode, and the target power is reset. The power demand control device according to any one of claims 1 to 4.

6. 6. The power demand control device according to claim 5, wherein the upper threshold value and the lower threshold value are values ​​that are set with a predetermined safety factor that depends on the prediction accuracy of the prediction unit with respect to the capacity of the storage battery when fully charged.

7. The power demand control device according to any one of claims 1 to 6, wherein the load suppression control amount in the load suppression priority mode is commanded with a predetermined range, and when the commanded control amount is not a predetermined maximum control amount and when a predetermined condition is met, the load suppression control amount is increased relative to the command, with the maximum control amount as a limit, and the excess power corresponding to the increase is charged to the storage battery.

8. Computer, The power demand control device according to any one of claims 1 to 7 is operated as the power demand control device. Power demand control program.

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