JP2020054140A - Power supply system - Google Patents

Abstract

To provide a power supply system capable of reducing electricity charge by performing electric discharge of a power storage device according to the power purchase unit cost from a system power supply.SOLUTION: A power supply system comprises a power storage device (a first power storage device 10 (an accumulator battery 12), a second power storage device 20 (an accumulator battery 22), and a third power storage device 30 (an accumulator battery 32) capable of charging and discharging power from a system power supply K, an EMS 50 (a request amount prediction part) for predicting a discharge request amount, i.e., a discharge amount requested for the power storage devices, and an EMS 50 (assignment part) for assigning a discharge permission amount, i.e., a discharge amount permitted for the power storage devices, for the predicted discharge request amount. The EMS 50 (assignment part) groups a discharge permission time band, i.e., a time band for permitting discharge to the power storage devices, into multiple groups for each purchase unit cost of power from the system power supply K, and assigns discharge permission amount preferentially to the discharge request amount of the group of high power purchase unit cost.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a technology of a power supply system including a power storage device capable of charging and discharging power.

  Conventionally, the technology of a power supply system including a power storage device capable of charging and discharging power has been known. For example, as described in Patent Document 1.

  Patent Literature 1 describes a power supply system including a solar power generation unit and a power storage device capable of charging and discharging power from the solar power generation unit. In the power supply system, a time zone in which power is supplied from the power storage device to the load can be arbitrarily set by a customer. Normally, the unit price of the power purchased from the system power source differs depending on the time, and the unit price of the power purchase at midnight is set low. Then, by supplying the electric power charged in the middle of the night when the power purchase unit price is low to the load during a time period other than midnight, the electric power (purchased power) supplied from the system power supply in the time period can be reduced, and the electric power rate can be reduced. Can save money.

  However, if the power storage device is discharged according to the load in a time zone other than late at night, the power storage device cannot be discharged in a manner desired by the consumer when the power purchase unit price varies depending on the time. Specifically, if the power purchase unit price is highest in the latter half of the time period other than midnight, in order to save the electricity rate, the power stored in the power storage device during the time period when the power purchase unit price is the highest is considered. However, if the load is large in the first half of the time period other than midnight, there is a possibility that the power stored in the power storage device will be used up by the latter half of the highest unit price. On the other hand, if the discharge is started in the latter half of the time zone other than late at night to avoid this, the power stored in the power storage device cannot be completely discharged, and the power stored in the power storage device may be excessive.

JP 2014-45635 A

  The present invention has been made in view of the above situation, and a problem to be solved is to reduce an electricity bill by discharging a power storage device according to a unit purchase price from a system power supply. It is to provide a power supply system.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, in claim 1, a power storage device capable of charging and discharging power from a system power supply, a request amount prediction unit that predicts a discharge request amount that is a discharge amount required for the power storage device, and the predicted discharge amount An allocation unit that allocates a discharge permission amount that is a discharge amount permitted to the power storage device to the required amount, wherein the allocation unit is a discharge permission time period that is a time zone in which the power storage device is allowed to discharge. The bands are grouped into a plurality of groups for each power purchase unit price of the power from the system power supply, and a discharge permission amount is preferentially assigned to the discharge request amount of a group having a high power purchase unit price.

  In claim 2, the power storage device includes a possible amount prediction unit that predicts a dischargeable amount that is a discharge amount that can be discharged, the plurality of power storage devices are provided, and the required amount prediction unit includes a power storage device. The discharge request amount is calculated for each of the power storage devices according to a ratio of the dischargeable amount of each of the power storage devices to a total dischargeable amount, which is a sum of the dischargeable amounts, and the allocating unit calculates When the dischargeable amount of the power storage device is equal to or greater than the required discharge amount of the power storage device, the requested discharge amount is set as the permitted discharge amount of the power storage device.

  In Claim 3, when the dischargeable amount of the power storage device is less than the required discharge amount of the power storage device, the allocating unit sets the dischargeable amount as the discharge permitted amount of the power storage device. is there.

  In Claim 4, the possible amount predicting unit calculates a value obtained by multiplying a maximum discharge amount per unit time of the power storage device by a total time of the group, and the dischargeable amount of the power storage device is the value. In the case of the above, the above value is set to the dischargeable amount.

  In a fifth aspect, the allocating unit preferentially allocates the discharge permission amount to the power storage device having the small dischargeable amount.

  According to a sixth aspect of the present invention, there is provided a control unit that controls a discharge amount from the power storage device in accordance with a discharge amount actually required for the power storage device, with the discharge permission amount determined by the allocating unit as an upper limit. The allocating unit stores the surplus as a preliminary dischargeable amount when the dischargeable amount is still excessive even after allocating the discharge permission amount, and the control unit determines the discharge determined by the allocation unit. If the permitted amount cannot actually cover the required discharge amount of the power storage device, the additional permitted discharge amount is assigned with the preliminary dischargeable amount as an upper limit.

  The present invention has the following effects.

  According to the first aspect, the electricity bill can be reduced by discharging the power storage device in accordance with the unit purchase price from the system power supply.

  According to the second aspect, since the discharge permission amount can be assigned to all the dischargeable power storage devices, it is possible to easily cope with a change in the power consumption of the load.

  According to the third aspect, the discharge permission amount can be set according to the dischargeable amount of the power storage device.

  According to the fourth aspect, the dischargeable amount according to the time from the start to the end of the group can be set.

  According to the fifth aspect, the number of power storage devices permitted to be discharged is likely to be increased, whereby it is possible to easily cope with a change in the power consumption of the load.

  According to the present invention, it is possible to correct the difference between the discharge permission amount assigned to the predicted discharge request amount and the actually requested discharge amount.

FIG. 1 is a block diagram showing a configuration of a power supply system according to an embodiment of the present invention. The figure which showed the power rate plan. The figure which showed the main flow which concerns on the discharge control of a storage battery. The figure which showed the flow of the discharge permission amount allocation process. The figure which showed the flow of the discharge permission amounts _{m and n} determination processing of each storage battery. The figure which showed the flow of the discharge amount _{m, n} calculation processing of each storage battery. The figure which showed the flow of the surplus discharge permission amount allocation processing. The figure which showed the flow of discharge control processing. The figure which showed the flow of the discharge permission amount additional allocation process. The figure which showed an example of allocation of the discharge permission amount.

  Hereinafter, a power supply system 1 according to an embodiment of the present invention will be described with reference to FIG.

  The power supply system 1 illustrated in FIG. 1 supplies power from a system power supply K and power generated using sunlight to a load H. The power supply system 1 is provided in an apartment house, and supplies power to a load H (for example, a plurality of home appliances) of the apartment house. The power supply system 1 mainly includes a first power storage system 10, a second power storage system 20, a third power storage system 30, a first sensor 41, a second sensor 42, a third sensor 43, and an EMS 50. Hereinafter, the first power storage system 10, the second power storage system 20, and the third power storage system 30 may be collectively referred to as a “power storage system”. In addition, the first sensor 41, the second sensor 42, and the third sensor 43 may be collectively referred to as a "sensor".

  The first power storage system 10 stores power generated by using sunlight or supplies the power to the load H. The first power storage system 10 includes a solar power generation unit 11, a storage battery 12, and a hybrid inverter 13.

  The solar power generation unit 11 is a device that generates power using sunlight. The solar power generation unit 11 is configured by a solar cell panel or the like. The solar power generation unit 11 is installed in a sunny place such as on a roof of a house, for example.

  The storage battery 12 is configured to be able to charge electric power. The storage battery 12 is composed of, for example, a lithium ion battery. The storage battery 12 is connected to the solar power generation unit 11 via a hybrid power conditioner 13 described later.

  The hybrid power conditioner 13 appropriately converts electric power (hybrid power conditioner). The hybrid inverter 13 can output the power generated by the photovoltaic power generation unit 11 and the power discharged from the storage battery 12 to the load H, and the power generated by the photovoltaic power generation unit 11 and the power from the system power supply K. Is output to the storage battery 12. The hybrid inverter 13 is configured to be able to acquire information on the performance and operating state of the solar power generation unit 11 and the storage battery 12. Hybrid power conditioner 13 is connected to first connection point P1 of power path A that supplies power from system power supply K to load H.

  The hybrid power conditioner 13 of the first power storage system 10 configured as described above can perform a load following operation that adjusts electric power to be discharged (output) based on a detection result of the first sensor 41 described later and the like.

  Second power storage system 20 is configured similarly to first power storage system 10 except that hybrid power conditioner 23 is connected to second connection point P2 on the upstream side of power path A from first power storage system 10. . Specifically, the solar power generation unit 21, the storage battery 22, and the hybrid inverter 23 of the second power storage system 20 correspond to the solar power generation unit 11, the storage battery 12, and the hybrid inverter 13 of the first power storage system 10, respectively.

  The third power storage system 30 is configured similarly to the first power storage system 10 except that the hybrid power conditioner 33 is connected to a third connection point P3 on the power path A upstream of the second power storage system 20. . Specifically, the solar power generation unit 31, the storage battery 32, and the hybrid inverter 33 of the third power storage system 30 correspond to the solar power generation unit 11, the storage battery 12, and the hybrid inverter 13 of the first power storage system 10, respectively.

  The first sensor 41 is provided between the first connection point P1 and the second connection point P2 on the power path A. Further, the first sensor 41 is provided so as to be adjacent to the upstream side (system power supply K side) of the first connection point P1 (so that a connection point between the power path A and another power storage system is not interposed). The first sensor 41 is configured to supply a voltage (supply voltage) and a current (supply current) of electric power (for example, electric power supplied to the load H or the like or electric power reversely flowing to the system power supply K) flowing through the provided location. ) Is detected.

  The second sensor 42 is configured in the same manner as the first sensor 41 except that the second sensor 42 is provided between the second connection point P2 and the third connection point P3 in the power path A.

  The third sensor 43 is configured in the same manner as the first sensor 41 except that the third sensor 43 is provided between the third connection point P3 and the system power supply K in the power path A.

  The EMS 50 is an energy management system that manages the operation of the power supply system 1. The EMS 50 includes an arithmetic processing unit such as a CPU, a storage unit such as a RAM and a ROM, and an input / output unit such as a touch panel. Various information, programs, and the like used when controlling the operation of the power supply system 1 are stored in the storage unit of the EMS 50 in advance. The arithmetic processing unit of the EMS 50 can operate the power supply system 1 by executing the program and performing predetermined arithmetic processing using the various information.

  The EMS 50 is electrically connected to the hybrid inverters 13, 23, 33. The EMS 50 can transmit a predetermined signal to the hybrid inverters 13, 23, and 33 to control the operation of the storage batteries 12, 22, and 32 (for example, charge and discharge of the storage batteries 12, 22, and 32). Also, the EMS 50 is configured to be able to input a predetermined signal from the hybrid inverters 13, 23, and 33, and to store the remaining power (the amount of stored power) of the storage batteries 12, 22, and 32 and the power from the storage batteries 12, 22, and 32. The discharge amount can be obtained.

  Hereinafter, the power supply mode in the power supply system 1 configured as described above will be briefly described.

  In the present embodiment, the power supply mode in the power supply system 1 includes two modes according to the mode of charging and discharging the storage batteries 12, 22, and 32 of the power storage systems 10, 20, and 30. More specifically, the power supply mode includes a mode in which charging / discharging of the storage batteries 12, 22, and 32 is performed without receiving an instruction from the EMS 50 (hereinafter, referred to as a “first mode”), and an instruction from the EMS 50. (Hereinafter, referred to as “second embodiment”). The first aspect and the second aspect are configured to be arbitrarily switchable.

  First, the first embodiment will be described.

  In this case, the storage batteries 12, 22, and 32 maintain a chargeable / dischargeable state. Then, the storage batteries 12, 22, and 32 perform charging and discharging by the load following operation based on the detection results of the sensors 41, 42, and 43.

  Specifically, when the sensors 41, 42, and 43 detect the power flowing to the load H side, the storage batteries 12, 22, and 32 discharge based on the detection result. In addition, when the sensors 41, 42, and 43 detect the power flowing to the system power supply K side, the storage batteries 12, 22, and 32 perform charging based on the detection result. The storage batteries 12, 22, and 32 do not perform charging / discharging (standby) when the sensors 41, 42, and 43 do not detect the power flowing to the load H side and the system power supply K side.

  Thus, for example, in the first power storage system 10, when the first sensor 41 detects the power flowing to the load H side, the power discharged from the storage battery 12 flows to the power path A based on the detection result. . In this case, if there is power generated by the solar power generation unit 11 (generated power), the generated power also flows to the power path A. Thus, the electric power flowing to the electric power path A flows to the load H side.

  Further, for example, in the first power storage system 10, when the first sensor 41 detects the power flowing to the system power supply K side, the power generated by the solar power generation unit 11 is stored in the storage battery 12 based on the detection result. Charged. Note that, of the power generated by the solar power generation unit 11, the power that cannot be fully charged by the storage battery 12 flows to the power path A and flows to the system power supply K side.

  Further, for example, in the first power storage system 10, when the first sensor 41 does not detect the power flowing to the load H side and the system power supply K side, the power generated by the solar power generation unit 11 is transferred to the power path A. However, the storage battery 12 does not charge or discharge. Thus, the electric power flowing to the electric power path A flows to the load H side.

  Although the first power storage system 10 has been described as an example, the same applies to the second power storage system 20 and the third power storage system 30.

  Thus, in the first mode, the power from the power storage system located on the downstream side with respect to the upstream side can be preferentially supplied to the load H by the charging / discharging mode of the storage batteries 12, 22, 32 as described above. Become. If the power consumption of the load H is still insufficient even when the power is supplied from the third power storage system 30 located on the most upstream side, the insufficient power is purchased from the system power supply K.

  Next, the second embodiment will be described.

  In this case, the state in which the storage batteries 12, 22, and 32 can be charged and discharged is changed according to the instruction of the EMS 50 via the corresponding hybrid inverters 13, 23, and 33. Specifically, the instruction of the EMS 50 includes a discharge instruction, a charge instruction, and a standby instruction.

  The discharge instruction is to change the storage batteries 12, 22, and 32 to a dischargeable and non-chargeable state. The charging instruction is to change the storage batteries 12, 22, and 32 to a chargeable and non-dischargeable state, and to actually start charging. The standby instruction is to change the storage batteries 12, 22, and 32 to a state in which charging and discharging cannot be performed.

  Thus, for example, when the EMS 50 issues a discharge instruction to the storage battery 12 of the first power storage system 10, the storage battery 12 performs discharge by the load following operation. That is, when the first sensor 41 detects the power flowing to the load H side, the power discharged from the storage battery 12 flows to the power path A based on the detection result. In this case, if there is power generated by the solar power generation unit 11, the generated power also flows to the power path A. Thus, the electric power flowing to the electric power path A flows to the load H side.

  Further, for example, when the EMS 50 issues a charge instruction to the storage battery 12 of the first power storage system 10, the storage battery 12 starts charging. If there is power generated by the solar power generation unit 11, the storage battery 12 charges the generated power. In addition, when the generated power alone is insufficient, or when there is no generated power, the storage battery 12 uses the power flowing through the power path A (for example, the power purchased from the system power supply K or the power of the solar power generation unit of another power storage system). Charge).

  Further, for example, when the EMS 50 issues a standby instruction to the storage battery 12 of the first power storage system 10, the storage battery 12 does not perform charging and discharging.

  Although the first power storage system 10 has been described as an example, the same applies to the second power storage system 20 and the third power storage system 30.

  Thus, in the second embodiment, charging / discharging is performed in an arbitrary power storage system irrespective of the position (upstream or downstream) of the power storage system according to the charging / discharging mode of the storage batteries 12, 22, and 32 as described above. .

  In addition, the EMS 50 can issue a discharge instruction and a standby instruction to the storage batteries 12, 22, and 32 via the hybrid inverters 13, 23, and 33. Here, the “discharge instruction” means that the storage batteries 12, 22, and 32 can be discharged (load following operation is possible), and the “standby state” is that the storage batteries 12, 22, and 32 cannot be discharged. (Load following operation is impossible).

  Further, the EMS 50 stores information on the electricity bill plan in the storage unit. The electricity bill plan indicates a unit price of electricity purchased from the system power supply K at each time (an electricity bill per 1 kWh). The unit price of the power purchased from the system power source K includes not only the unit price of the power purchased from the system power source K (power company) at each time but also the purchase price from the retailer (via the retailer). It also includes the power purchase unit price of the power to be used at each time.

  In the electricity tariff plan shown in FIG. 2, the unit price at 0 to 7 o'clock is 15 [yen / kWh], the unit price at 7 to 10 o'clock is 25 [yen / kWh], and 10:00 to 17:00. Is 35 [yen / kWh], and the power purchase price from 17:00 to 24:00 is 25 [yen / kWh].

  The EMS 50 causes the storage batteries 12, 22, and 32 to charge the electric power from the system power supply K in a time period (0 to 7:00) when the unit price of power purchase is the lowest. As described above, the storage batteries 12, 22, and 32 are charged with the power with a low power rate, and on the other hand, during the time period (7 to 24:00) other than the time period (0 to 7:00) where the unit price of power purchase is the lowest. And discharge from the storage batteries 12, 22, and 32, and supplies the discharged power to the load H. As a result, it is possible to reduce the electricity bill.

  On the other hand, when the discharge of the storage batteries 12, 22, and 32 is started at the start time (7 o'clock) of the time period (7 to 24:00) where the discharge from the storage batteries 12, 22, and 32 is possible, the time zone in which the unit price of electric power is the highest is obtained. (At 10 to 17 o'clock), there is a possibility that the remaining power of the storage batteries 12, 22, and 32 becomes insufficient. On the other hand, if the storage batteries 12, 22, and 32 start discharging at the start time (10:00) of the time zone (10 to 17:00) when the unit price of electric power is the highest, the stored power of the storage batteries 12, 22, and 32 may not be used up. There is.

  Therefore, in the power supply system 1 according to the present embodiment, in order to solve the above-described problem, the future power demand is predicted based on information (see FIG. 2) on the electricity bill plan and past performance. Based on the (power consumption of the load H) and the power generated by the photovoltaic power generation units 11, 21, and 31, a time period for discharging the storage batteries 12, 22, and 32, and a discharge plan for planning a discharge amount in the time period. Perform control.

  Also, even if the discharge amounts of the storage batteries 12, 22, and 32 are planned by the discharge plan control, the actual power consumption of the load H and the actual generated power of the solar power generation units 11, 21, and 31 may differ from the prediction. In this case, the actually required discharge amount from the storage batteries 12, 22 and 32 is different (shifted) from the discharge amount of the storage batteries 12, 22 and 32 planned by the discharge plan control. Thus, in the power supply system 1 according to the present embodiment, the discharge amount of the storage batteries 12, 22, and 32 planned by the discharge plan control and the actually required discharge amount from the storage batteries 12, 22, and 32 are determined. A real-time correction control for correcting the deviation in real time (when actually performing discharge) is performed.

  Hereinafter, discharge control of the storage batteries 12, 22, and 32 by the EMS 50 will be described with reference to FIGS.

  FIG. 3 shows a main flow relating to the discharge control of the storage batteries 12, 22, and 32. Steps S10 and S11 of steps S10 to S16 shown in FIG. 3 are processes related to the above-described discharge plan control. On the other hand, steps S12 to S16 are processes related to the above-described real-time correction control. The discharge planning control (steps S10 and S11) is performed before the day when the storage batteries 12, 22, and 32 are actually discharged (hereinafter, also referred to as “the current day”), for example, one day before the day (hereinafter, “the day”). The day before).

  First, the discharge plan control in steps S10 and S11 will be described.

  In step S10 shown in FIG. 3, the EMS 50 determines whether or not the current time is the discharge permission amount allocation processing time. Here, the “permitted discharge amount allocation processing time” refers to the time at which the below-described permitted discharge amount allocation processing (step S11) is performed. The discharge permission amount allocation processing time is set, for example, at 23:00 on the day before the day (current day) when the storage batteries 12, 22, and 32 are actually discharged.

  If the EMS 50 determines that the current time is the discharge permission amount allocation processing time (“YES” in step S10), the process proceeds to step S11. On the other hand, if the EMS 50 determines that the current time is not the discharge permission amount allocation processing time (“NO” in step S10), the process proceeds to step S12.

  In step S11, the EMS 50 performs a discharge permission amount assignment process. Hereinafter, the allowable discharge amount allocation process will be described with reference to FIG.

  In step S20, the EMS 50 divides the discharge permission time zone into groups. Here, the “discharge permitted time zone” refers to a time zone in which the storage batteries 12, 22, and 32 are allowed to discharge. As described above, the EMS 50 sets the time zone (0 to 7:00) with the lowest power purchase unit price as the charging time zone for charging the storage batteries 12, 22, and 32 (see FIG. 2). Then, the EMS 50 sets the time zone (7 to 24:00) other than the time zone (charge time zone) with the lowest power purchase unit price as the “discharge permitted time zone”. In step S20, the EMS 50 divides the discharge permission time zone (7 to 24:00) into groups for each unit price of power purchased from the system power supply K.

  Specifically, the EMS 50 assigns the discharge permission time zone (7 to 24:00) to each group m (m = 1, 2,...) So that the time zones having the same power purchase unit price are in the same group. ). In the present embodiment, the EMS 50 sets the discharge permission time zone (7 to 24:00), the power purchase unit price of 35 [yen / kWh] (10 to 17:00), and the power purchase unit price of 25 [yen]. / KWh] (7-10 o'clock and 17-24 o'clock). Here, the time zone (10 to 17:00) in which the unit price is 35 [yen / kWh] is group 1 (m = 1), and the time zone (7 to 10) in which the unit price is 25 [yen / kWh]. Time and 17:00 to 24:00) are group 2 (m = 2).

  After performing the process in step S20, the EMS 50 proceeds to step S21.

In step S21, the EMS 50 calculates a required discharge amount _m . Here, the “requested discharge amount” indicates a discharge amount required for the storage batteries 12, 22 and 32 (a discharge amount from the storage batteries 12, 22 and 32 necessary to cover the power consumption of the load H). is there. The suffix “m” indicates the required discharge amount in the period of each group m divided in step S20.

The required discharge amount _m is calculated based on the past performance and the like, the power consumption of the load H of the day (the predicted value of the power consumption of the load H), and the solar power generation unit 11 predicted based on the past performance and the like. Calculated from the difference between the generated power of 21 and 31 (the predicted value of the generated power of solar power generation units 11 and 21 and 31). The required discharge amount _m is calculated by calculating the required discharge amount at each time of the group m and adding the required discharge amount at each time of the group m.

Therefore, when the predicted value of the power generated by the photovoltaic power generation units 11, 21, 31 in the group m is equal to or greater than the predicted value of the power consumption of the load H in the group m (that is, the photovoltaic power generation units 11, 21, 31). When it is predicted that the power consumption of the load H can be covered by the generated power alone), the required discharge amount _m is zero. On the other hand, when the predicted value of the generated power of the photovoltaic power generation units 11, 21 and 31 in the group m is less than the predicted value of the power consumption of the load H in the group m (that is, the predicted value of the photovoltaic power generation units 11, 21 and 31). In the case where it is predicted that the generated power alone cannot cover the power consumption of the load H), the required discharge amount _m is calculated based on the predicted value of the power consumption of the load H in the group m by the photovoltaic power generation unit 11 in the group m. It is calculated by subtracting the predicted values of the generated power of 21 and 31. That is, (the required discharge amount _m ) = (the predicted value of the power consumption of the load H in the group m)-(the predicted value of the generated power of the solar power generation units 11, 21, and 31 in the group m).

In the present embodiment, as shown in FIG. 10, the required discharge amount _{1 for} group 1 (10 to 17 o'clock) is 3000 [Wh], and the required discharge amount _{2 for} group 2 (7 to 10 o'clock and 17 to 24:00). Is 4000 [Wh].

  After performing the process of step S21, the EMS 50 proceeds to step S22.

In step S22, the EMS 50 performs a discharge permission amount _{m, n} determination process. Here, the “permitted discharge amount” indicates the discharge amount permitted to the storage batteries 12, 22, and 32 (the upper limit of the discharge amount of the storage batteries 12, 22, and 32). The suffix “m” indicates the discharge permission amount in the period of each group m divided in step S20. The subscript “n” indicates that the discharge permission amount of each storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32). That is, the discharge permission amount _{m, n} determination process determines how much discharge is permitted from each storage battery n with respect to the required discharge amount _m calculated in step S21. In other words, in the discharge permission amounts _{m and n} determination processing, the discharge amount is assigned to each storage battery n during the period of each group m with respect to the required discharge amount _m calculated in step S21. The details of the discharge permission amounts _{m and n} determination processing will be described later.

  The EMS 50 repeats the processing of steps S21 and S22 in order from the group having the highest power purchase unit price. That is, the processing of steps S21 and S22 is performed for the group 1 having the highest power purchase unit price (10 to 17:00 when the power purchase unit price is 35 [yen / kWh]). The processing of steps S21 and S22 is performed for Group 2 (the power purchase unit price is 25 [yen / kWh], 7 to 10:00 and 17:00 to 24:00) with the second highest unit price. In this way, the processing of steps S21 and S22 is performed for all the groups m.

  After performing the processes of steps S21 and S22 for all the groups m, the EMS 50 proceeds to step S23.

In step S23, the EMS 50 calculates the possible preliminary discharge amount _n . Here, the “preliminary dischargeable amount” indicates the amount of discharge that can be allocated in excess of the allowable discharge amount _{m, n} determined in step S22 in real-time correction control (processing from steps S12 to S16) described below. It is. In this process, the EMS 50 sets the remaining dischargeable amount _n (the details will be described later in the description of Step S22) after the discharge permission amount _{m, n} determination process (Step S22) is completed as the preliminary dischargeable amount _n .

That is, if the dischargeable amount of the storage battery n does not become 0 even after the discharge permission amount _n is assigned, the preliminary dischargeable amount n is generated. On the other hand, when the discharge permission amount _n is assigned, when the dischargeable amount of the storage battery n becomes 0, the preliminary dischargeable amount _n does not occur (becomes 0). The preliminarily dischargeable amount _n calculated in this way is used in real-time correction control (processing from steps S12 to S16) described later.

  After performing the process in step S23, the EMS 50 ends the discharge permission amount allocation process (ie, step S11 in FIG. 3) illustrated in FIG. After performing the process of step S11, the EMS 50 ends the main flow illustrated in FIG.

Next, the details of the discharge permission amounts _{m and n} determination processing (step S22 shown in FIG. 4) will be described with reference to FIG.

In step S30, the EMS 50 performs a dischargeable amount _{m, n} calculation process. Here, the "dischargeable amount" indicates the amount of power that can be discharged from the storage batteries 12, 22, and 32. The suffix “m” indicates the dischargeable amount in the period of each group m divided in step S20. The suffix “n” indicates that each storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32) is the dischargeable amount. That is, the dischargeable amount _{m, n} calculation process calculates how much discharge is possible from each storage battery n during the period of each group m. The details of the dischargeable amount _{m, n} calculation process will be described later.

In the present embodiment, as shown in FIG. 10, before the discharge permission amount is assigned to the group 1 (at 10 to 17 o'clock), the dischargeable amounts _{1 and} 12 of the storage battery ₁₂ are 4000 [Wh] and the dischargeable amount of the storage battery 22 is _{1, 22} is 3000 [Wh], the dischargeable quantity _1,32 of the battery 32 is 1000 [Wh], the sum (total dischargeable quantity) of dischargeable quantity _{1, n} of the battery n in 8000 [Wh] There is.

  After performing the process in step S30, the EMS 50 proceeds to step S31.

The EMS 50 repeats the following processes from step S31 to S37 in order from the storage battery n having the smaller dischargeable amounts _{m and n} calculated in step S30. That is, the processes from steps S31 to S37 are performed on the storage battery _n having the smallest dischargeable amount _{m, n} , and when the process is completed, the processes from steps S31 to S37 are performed on the storage battery n having the second smallest dischargeable amount _{m, n.} The processing up to is performed. In this way, the processes from steps S31 to S37 are performed for all the storage batteries n.

In step S31, the EMS 50 calculates the total dischargeable amount _m . Here, the “total dischargeable amount” indicates the total dischargeable amount of each storage battery n. The suffix “m” indicates the dischargeable amount in the period of each group m divided in step S20. The total dischargeable amount _m is calculated by summing the dischargeable amounts _{m and n} of the storage battery n for which the discharge permission amounts _{m and n} (determined in step S34 or S35 described below) have not been determined. After performing the process of step S31, the EMS 50 proceeds to step S32.

In step S32, the EMS 50 calculates the required discharge amounts _{m and n} for the storage battery n. The required discharge amount _{m, n} is calculated by the required discharge amount _m × (dischargeable amount _{m, n} / total dischargeable amount _m ). That is, the required discharge amount _{m, n} is calculated by subtracting the required discharge amount _m (the required discharge amount during the period of the group m) calculated in step S21 from the dischargeable amount _{m, n} (the possible discharge amount of the storage battery n during the period of the group m). Is multiplied by a ratio of the total dischargeable amount _m to the total dischargeable amount _m (the total dischargeable amount in the period of the group m). Thereby, the required discharge amount _{m, n} is set for each storage battery n according to the dischargeable amount _n .

In the present embodiment, the required discharge amount _1, 12 for the storage batteries 12 in the group 1 (10 to 17 o'clock) is the required discharge amount ₁ (3000 [Wh]) × ｛dischargeable amount _{1, 12} (4000 [Wh]). / Total dischargeable amount ₁ (8000 [Wh])} is calculated as 1500 [Wh]. By similar calculation, the discharge demand _{1, 22} for the storage battery 22 of group 1 (at 10-17) is 1125 [Wh], the discharge demand _1,32 for storage battery 32 is calculated to be 375 [Wh].

  After performing the process in step S32, the EMS 50 proceeds to step S33.

In step S33, the EMS 50 determines whether or not the required discharge amount _{m, n} ≦ the dischargeable amount _{m, n} . Here, the required discharge amounts _{m and n} are calculated in step S32. The dischargeable amounts _{m and n} are calculated in step S30. If the EMS 50 determines that the required discharge amount _{m, n} ≦ the possible discharge amount _{m, n} (“YES” in step S33), the process proceeds to step S34. On the other hand, if the EMS 50 determines that the required discharge amount _{m, n} ≦ the dischargeable amount _{m, n} is not satisfied (“NO” in step S33), the process proceeds to step S35.

The case of "YES" in the step S33, a dischargeable quantity _m, meet discharge requirements _m, a _n by _n (cover) shows that it is possible. On the other hand, in the case of "NO" in the step S33, a dischargeable quantity _m, the discharge request amount _m by _n, satisfy _n (cover) that is not able to have.

In step S34, the EMS 50 determines the discharge permission amounts _{m and n} . In this process, the EMS 50 sets the required discharge amount _{m, n} calculated in step S32 as the permitted discharge amount _{m, n} .

On the other hand, in step S35, the EMS 50 determines the discharge permission amounts _{m and n} by a method different from that in step S34. In this process, the EMS 50 sets the dischargeable amounts _{m and n} calculated in step S30 as discharge permission amounts _{m and n} .

In the present embodiment, since the required discharge amount _{m, n} ≦ the dischargeable amount _{m, n} in each storage battery n (“YES” in step S33), as shown in FIG. discharge allowances for battery 12) _{1, 12} are the same 1500 as the discharge demand _1,12 [Wh], the same 1125 discharge allowances _{1, 22} for the battery 22 and the discharge demand _{1, 22} [Wh], the storage battery 32 the same 375 [Wh] next discharge allowances _1,32 and discharge demand _1,32 for a total of the discharge allowances _{1, n} of the battery n (total discharged allowances) becomes 3000 [Wh].

  After performing the processing of Step S34 or Step S35, the EMS 50 proceeds to Step S36.

In step S36, the EMS 50 calculates the remaining dischargeable amount _n of the storage battery n. Discharge allowances _{m, n} determining process shown in FIG. 5, since a high group m is purchased electricity unit price is intended to repeat the number of groups in order (see FIG. 4), of the dischargeable quantity _n, already before the group This is because the allocated discharge permission amount cannot be used. That is, it can be said that the process of step S36 is a process of updating the dischargeable amount _n used in steps S31 to S33 and S35. The remaining dischargeable amount _n, the discharge permit of the previous group _{m, n-allocated} before dischargeable amount _n, the discharge allowances _m, is calculated by subtracting the _n.

In the present embodiment, the remaining dischargeable amounts _{2 and} 12 of the storage batteries 12 of the group 2 (7 to 10 o'clock and 17 to 24 o'clock) are calculated from the dischargeable amount ₁ (4000 [Wh]) before the allocation of the group 1. , 2500 [Wh] by subtracting the allowable discharge amounts _1,12 (1500 [Wh]) of the storage batteries 12 in the group 1. By similar calculation, a dischargeable amount _2,22 of the battery 22 is 1875 [Wh], the dischargeable quantity _2,32 of the battery 32 is calculated to be 625 [Wh], the total dischargeable quantity _{2, n} of the battery n (Total dischargeable amount) is calculated as 5000 [Wh].

  After performing the process in step S36, the EMS 50 proceeds to step S37.

In step S37, the EMS 50 calculates the remaining required discharge amount _m . This is because the processes in steps S31 to S35 are repeated for the number of storage batteries n, and thus a part of the required discharge amount _m is covered by the discharge permission amount already allocated in the previous storage battery n. That is, the process of step S37 can be said to be a process of updating the required discharge amount _m used in steps S31 to S34. The remaining required discharge amount _m is calculated by subtracting the permitted discharge amounts _{m and n} allocated in step S34 or S35 from the required discharge amount _m calculated in step S21.

When the discharge permission amount determination processing (step S22) for group 1 is completed, the discharge permission amount determination processing (step S22) is next performed for group 2. However, the discharge permission amount _{2, n,} the remaining dischargeable amount calculated in step S36 n (dischargeable amount _2,12 = 2500 [Wh], the dischargeable quantity _2,22 = 1875 [Wh], the dischargeable quantity _2,32 = 625 [Wh ]) (Steps S31 to S33 and S35). Therefore, in step S32, the required discharges _2, 12 for the storage batteries 12 of the group 2 (7 to 10 o'clock and 17 to 24 o'clock) are 2000 [Wh], the required discharges _2, 22 for the storage batteries 22 are 1500 [Wh], The required discharge amounts _{2 and} 32 for the storage battery 32 are calculated as 500 [Wh]. Since the required discharge amount _{m, n} ≦ the dischargeable amount _{m, n} (“YES” in step S33), as shown in FIG. 10, the discharge to the storage batteries 12 in the group 2 (7 to 10 o'clock and 17 to 24 o'clock) is performed. The permitted amounts _{2 and 12} are 2000 [Wh], the same as the required discharge amounts ₂ and ₁₂ , the discharge permitted amounts _{2 and} 22 for the storage battery 22 are 1500 [Wh] the same as the required discharge amounts ₂ and _22, and the discharge permitted amounts _{2 and 2 are 32} are the same 500 [Wh] next discharge demand _2,32, total discharge allowances _{2, n} of the battery n (total discharged allowances) becomes 4000 [Wh].

  The EMS 50 performs the processing from steps S31 to S37 for all the storage batteries n, thereby terminating the discharge permission amounts m and n determination processing illustrated in FIG. 5 (that is, step S22 illustrated in FIG. 4), and proceeds to step S23. I do. The processing in step S23 is as described above.

As described above, in step S23, the EMS 50 sets the remaining dischargeable amount _n after the completion of the discharge permission amount _{m, n} determination process (step S22) as the preliminary dischargeable amount _n . The preliminarily dischargeable amount ₁₂ of the storage battery 12 is obtained by subtracting the dischargeable amounts _1,12 (2000 [Wh]) of the storage battery 12 in the group 2 from the dischargeable amount ₁ (2500 [Wh]) before the allocation of the group 2. , 500 [Wh]. By the same calculation, the pre-dischargeable amount ₂₂ of the storage battery 22 is calculated to be 375 [Wh], and the pre-dischargeable amount ₃₂ of the storage battery 32 is calculated to be 125 [Wh].

Next, details of the dischargeable amount _{m, n} calculation process (step S30 shown in FIG. 5) will be described with reference to FIG.

In step S40, the EMS 50 determines whether or not the dischargeable amount _n <(discharge capacity _n ) × (time belonging to group m). As described above, the “dischargeable amount _{n 1} ” indicates the amount of power that can be discharged from the storage battery n. The “discharge capacity _{n 1} ” indicates the maximum discharge amount of the storage battery n per unit time (1 hr). The “time belonging to the group m” indicates the total time of the group m. For example, the time belonging to the group 1 (10 to 17 o'clock) is 7 hours.

If the EMS 50 determines that the dischargeable amount _n <(discharge capacity _n ) × (time belonging to the group m) is satisfied (“YES” in step S40), the process proceeds to step S41. On the other hand, when the EMS 50 determines that the dischargeable amount _n <(discharge capability _n ) × (time belonging to the group m) is not satisfied (“NO” in step S40), the process proceeds to step S42.

  Note that “YES” in step S40 indicates that the storage battery n cannot be discharged if the storage battery n is discharged at the maximum capacity (maximum discharge amount) during the time belonging to the group m. On the other hand, the case of “NO” in step S40 indicates that the storage battery n can be discharged even when the storage battery n is discharged at the maximum capacity (maximum discharge amount) during the time belonging to the group m. .

In step S41, the EMS 50 determines a dischargeable amount (dischargeable amount _{m, n} ) of the storage battery n in the group m. The EMS 50 sets the dischargeable amount (dischargeable amount _{n 1} ) of the storage battery n to the dischargeable amounts _{m and n} .

In step S42, the EMS 50 determines the dischargeable amount (dischargeable amount _{m, n} ) of the storage battery n in the group m by a method different from that in step S41. The EMS 50 sets (discharge capacity _{n 1} ) × (time belonging to group m) as dischargeable amounts _{m and n} .

The EMS 50 repeats the processing from step S40 to S42 for the number of storage batteries n. In this way, the processes from steps S40 to S42 are performed for all the storage batteries n. The EMS 50 performs the processes from steps S40 to S42 for all the storage batteries n, and ends the dischargeable amount _{m, n} calculation process (step S30 shown in FIG. 5) shown in FIG.

The EMS 50 shifts to step S31 after finishing the dischargeable amount _{m, n} calculation process (step S30 shown in FIG. 5) shown in FIG. The processing after step S31 is as described above.

  In this way, the discharge planning control composed of steps S10 and S11 is completed (see FIG. 3). The discharge from the storage battery n is performed on the current day based on the time period and the discharge amount (discharge permission amount determined in step S34 or S35 shown in FIG. 5) planned for the previous day by the discharge plan control. .

  As described above, based on the predicted value of the power consumption of the load H and the predicted value of the generated power of the photovoltaic power generation units 11, 21, and 31 on the day, the amount of discharge required for each storage battery 12, 22, and 32 (the required amount of discharge). ) Is calculated (step S21 shown in FIG. 4), and the amount of discharge (discharge permitted amount) permitted to each storage battery 12, 22, 32 is determined (step S22 shown in FIG. 4). At this time, by performing the processing of steps S21 and S22 in order from the group having the highest power purchase unit price (see FIG. 4), the discharge is always started from the start time (7:00) of the time period in which the discharge is permitted (discharge permitted time period). Instead of starting, preferentially discharging (allocating a discharge permission amount) from a group with a high power purchase unit price (time period (10 to 17:00) when the power purchase unit price is 35 [yen / kWh]) Becomes

  Thus, it is possible to avoid a situation in which the remaining storage capacity of the storage batteries 12, 22, and 32 is insufficient and the battery cannot be discharged during the time period (10 to 17 o'clock) when the power purchase unit price at which the discharge is to be performed most is highest. Therefore, it is possible to reduce the amount of electric power purchased from the system power supply K in the time period when the power purchase unit price is high, and it is possible to reduce the electricity rate.

  Also, in steps S21 and S22, if the dischargeable amount still remains even when the discharge permission amount is assigned to the time zone of the group having the highest power purchase unit price, the discharge is performed during the time period of the group having the next highest power purchase unit price. Assign allowances. Therefore, the discharge is not necessarily started from the start time (10:00) of the time zone (10 to 17:00) of the group having the highest purchase unit price, but the discharge is performed for the requested discharge amount from the start time (10:00). If the dischargeable amount is surplus even if the permitted amount is allocated, the discharge permitted amount is also allocated to a time period (7 to 10:00) that is earlier than the time period (10 to 17:00) of the group having the highest purchase unit price. be able to. Therefore, it is possible to avoid a situation in which the electric power stored in the storage batteries 12, 22, and 32 cannot be used up because the discharge is not performed at 7 to 10 o'clock.

  Further, in the present embodiment, according to the calculation formula shown in step S32 shown in FIG. 5, each storage battery 12, 22. The required discharge amount is assigned to 22 and 32, and when the dischargeable amount is equal to or more than the required discharge amount (YES in step S33), the allocated requested discharge amount is used as the permitted discharge amount (step S34). Thus, a discharge permission amount is allocated to all the dischargeable storage batteries 12, 22, and 32.

  By dispersing the dischargeable storage batteries 12, 22 and 32 in this manner, when there is a sudden change in the power consumption of the load H, the change in the discharge amount per storage battery 12, 22 and 32 is small. Help me. Therefore, it is possible to easily cope with a rapid change in the power consumption of the load H.

  In addition, on the day, the EMS 50 basically performs the load following operation of the storage batteries 12, 22, and 32 with the discharge permission amount allocated in the discharge plan control as an upper limit. However, the discharge capacity (per unit time) of each of the storage batteries 12, 22, and 32 Since there is a limit to the maximum discharge amount, there is a possibility that the power consumption of the load H may suddenly increase and the number of storage batteries may not be able to cope with this (the power consumption of the load H cannot be covered). On the other hand, in the present embodiment, the number of storage batteries that perform discharging tends to increase (dischargeable storage batteries 12, 22, and 32 are likely to be dispersed), and the total maximum discharge amount tends to increase accordingly. Therefore, even if the power consumption of the load H increases sharply, it is easy to cope with this (supply the power consumption of the load H).

  In the present embodiment, according to the calculation formula shown in step S32 shown in FIG. 5, each storage battery 12. Requested discharge amounts are assigned to the 22 and 32, and when the dischargeable amount is equal to or more than the requested discharge amount (YES in step S33), the allocated requested discharge amount is set as the permitted discharge amount (step S34). The dischargeable amount of each storage battery 12, 22, 32 may be used as the discharge permission amount as it is. In this case, if the allowable discharge amount is preferentially assigned to the storage batteries 12, 22, and 32 having a large dischargeable amount, the required discharge amount can be satisfied with a small number of storage batteries, and therefore the number of storage batteries to be discharged tends to decrease. .

  On the other hand, in the present embodiment, when assigning the discharge permission amount to each of the storage batteries 12, 22, 32 from the dischargeable amount of the storage batteries 12, 22, 32, this assignment is made based on the storage batteries 12, 22,. This is performed preferentially from 32 (see FIG. 5). As described above, when the priority is given to the storage batteries 12, 22 and 32 having a small dischargeable amount, in order to satisfy the required discharge amount, the storage batteries 12, 22 and 32 (the discharge is permitted) to which the discharge permission amount is allocated. Storage batteries 12, 22, and 32) are likely to increase (dischargeable storage batteries 12, 22, and 32 are dispersed). Therefore, it is easy to cope with the rapid fluctuation of the power consumption of the load H, and it is easy to cope with the rapid increase of the power consumption of the load H (to cover the power consumption of the load H). Become.

  Further, the dischargeable amount is not set to a value that cannot be actually discharged in consideration of the remaining amount of power and the discharge capacity of each of the storage batteries 12, 22, and 32 and the time belonging to the group m (FIG. 6). reference). As a result, it is possible to prevent the allowable discharge amount from exceeding the actually dischargeable discharge amount and being unnecessarily allocated.

  Next, the real-time correction control in steps S12 to S16 shown in FIG. 3 will be described. As described above, on the day, the EMS 50 performs the load following operation of the storage batteries 12, 22, and 32 based on the detection results of the first sensor 41, the second sensor 42, and the third sensor 43. The upper limit of the discharge amount from the storage battery is the discharge permission amount allocated in the discharge plan control in step S11. However, the actual power consumption of the load H and the actual power generated by the photovoltaic power generation units 11, 21 and 31 on the day may deviate from the predicted values. Therefore, the discharge amount is appropriately corrected by the following real-time correction control. .

  In step S12, the EMS 50 determines whether or not the current time is in the discharge permission time zone. As described above, the “discharge permission time zone” refers to a time zone in which the storage batteries 12, 22, and 32 are allowed to discharge. In the present embodiment, the discharge permitted time period is set to a time period (7 to 24:00) other than the time period (0 to 7:00) having the lowest power purchase unit price.

  If the EMS 50 determines that the current time is in the discharge permitted time zone (“YES” in step S12), the process proceeds to step S13. On the other hand, if the EMS 50 determines that the current time is not the discharge permission time zone (“NO” in step S12), the EMS 50 ends the main flow illustrated in FIG.

  In step S13, the EMS 50 determines whether or not the current time is the end time of the group m. Here, the “end time of the group m” indicates the time at which the group m ends completely. For example, when the group m is divided into a plurality of time zones as in the group 2, the last time zone (24:00 in the case of group 2) is the end time of group m. If the EMS 50 determines that the current time is not the end time of the group m (“NO” in step S13), the process proceeds to step S16.

  In step S16, the EMS 50 performs a discharge control process. Hereinafter, the discharge control process will be described with reference to FIG.

  In step S60, the EMS 50 acquires the current total house load. Here, the “house total load amount” indicates the total value of the load amount (power consumption of the load H (load H1, H2, H3) of each house) in each house. After performing the process of step S60, the EMS 50 proceeds to step S61.

  In step S61, the EMS 50 acquires the current PV total power generation amount. Here, the “PV total power generation amount” indicates the total amount of electric power generated by the solar power generation units 11, 21 and 31. After performing the process in step S61, the EMS 50 proceeds to step S62.

  In step S62, the EMS 50 calculates the current required discharge amount. The current required discharge amount is calculated by subtracting the current total PV power generation amount calculated in step S61 from the current total house load amount calculated in step S60. That is, (required discharge amount) = (current total house load amount) − (current total PV power generation amount). After performing the process in step S62, the EMS 50 proceeds to step S63.

  In step S63, the EMS 50 determines whether or not the required discharge amount> 0. If the EMS 50 determines that the required discharge amount> 0 (“YES” in step S63), the process proceeds to step S64. On the other hand, if the EMS 50 determines that the required discharge amount is not greater than 0 (“NO” in step S63), the EMS 50 ends the discharge control process illustrated in FIG.

  It should be noted that the case of “YES” in step S63 indicates that the storage batteries 12, 22, and 32 can be discharged (discharge is required). On the other hand, the case of “NO” in step S63 indicates that the discharge from the storage batteries 12, 22, and 32 is unnecessary.

In step S64, the EMS 50 calculates the remaining discharge permission amounts _{m and n} of all the storage batteries (storage batteries 12, 22, and 32). Here, the “remaining discharge allowable amount” indicates the remaining amount of the discharge allowable amount allocated (the day before) in the discharge planning control in step S11. The subscript “m” indicates the remaining discharge permission amount in the period of each group m divided in step S20. The suffix “n” indicates that the remaining discharge amount of each storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32).

The remaining discharge permission amounts _{m and n} are calculated by subtracting the actual discharge amounts _{m and n} from the discharge permission amounts _{m and n} assigned in step S11. Here, the "actual discharge amount" indicates the actual discharge amount from the storage batteries 12, 22, and 32. The subscript “m” indicates the actual discharge amount in the period of each group m divided in step S20. The subscript “n” indicates that the actual discharge amount of each storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32).

  After performing the process in step S64, the EMS 50 proceeds to step S65.

In step S65, the EMS 50 determines whether or not the remaining discharge permission amount _{m, n} <0 calculated in step S64. If the EMS 50 determines that the remaining discharge permission amount _{m, n} <0 (“YES” in step S65), the process proceeds to step S66. On the other hand, if the EMS 50 determines that the remaining discharge permission amount _{m, n} <0 is not satisfied ("NO" in step S65), the process proceeds to step S64.

  It should be noted that the case of “YES” in step S65 indicates that the actual discharge amount can be covered by the discharge permission amount (and the power generated by the solar power generation units 11, 21, and 31) allocated in step S11. On the other hand, the case of “NO” in step S65 indicates that the actual discharge amount is not covered by the discharge permission amount (and the power generated by the solar power generation units 11, 21, and 31) allocated in step S11.

  In step S66, the EMS 50 performs a discharge permission amount additional allocation process. The permitted discharge amount additional allocation process is a process of additionally allocating the permitted discharge amount beyond the permitted discharge amount allocated in step S11. Hereinafter, the discharge permission amount additional allocation process will be described with reference to FIG.

In step S70, the EMS 50 calculates the required additional discharge amounts _{m and n} . Here, the "required amount of additional discharge" indicates the amount of discharge additionally required for the storage batteries 12, 22, and 32. The subscript “m” indicates the required amount of additional discharge in the period of each group m divided in step S20. The suffix "n" indicates that the required amount of additional discharge of each storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32). The required additional discharge amounts _{m and n} are calculated based on, for example, the current purchase power from the system power supply K and the remaining time of the group m.

  After performing the process in step S70, the EMS 50 proceeds to step S71.

In step S71, the EMS 50 determines whether or not the preliminarily dischargeable amount _n > 0. The pre-dischargeable amount _n is calculated in step S23 shown in FIG. If the EMS 50 determines that the preliminarily dischargeable amount _n > 0 (“YES” in step S71), the process proceeds to step S72. On the other hand, if the EMS 50 determines that the predischargeable amount _n > 0 is not satisfied (“NO” in step S71), the process proceeds to step S73.

In step S72, the EMS 50 calculates the additional allocable amounts _{m and n} . Here, the “additional allocatable amount” indicates a discharge amount that can be additionally allocated to the storage batteries 12, 22, and 32. The subscript “m” indicates the additional allocable amount in the period of each group m divided in step S20. The subscript “n” indicates that the storage battery n (storage battery n = storage battery 12, storage battery 22, storage battery 32) is an additional allocable amount. In this process, the EMS 50 sets the preliminary dischargeable amount _n to the additional allocatable amounts _{m and n} .

On the other hand, in step S73, the EMS 50 calculates the additional allocable amounts _{m and n} by a method different from that in step S72. In this process, the EMS 50 sets the discharge permission amounts _{L and n} as the additionally assignable amounts. Here, the “permitted discharge amount _{L, n} ” indicates the permitted discharge amount in the group L with the lowest unit price of purchase among the permitted discharge amounts allocated to the storage battery n. In the present embodiment, the group L with the lowest power purchase unit price is Group 2 (7 to 10:00 and 17:00 to 24:00) whose power purchase unit price is 25 [yen / kWh].

  After performing the processing of Step S72 or Step S73, the EMS 50 proceeds to Step S74.

In step S74, the EMS 50 determines whether or not the additional allocatable amount _{m, n} ≧ the required amount of additional discharge _{m, n} . If the EMS 50 determines that the additional allocatable amount _{m, n} ≧ the additional discharge request amount _{m, n} (“YES” in step S74), the process proceeds to step S75. On the other hand, if the EMS 50 determines that the additional allocable amount _{m, n} ≧ the required amount of additional discharge _{m, n} is not satisfied (“NO” in step S74), the process proceeds to step S76.

The case of “YES” in step S74 indicates that the additional allocable amounts _{m and n} calculated in step S72 or S73 can cover the additional discharge request amounts _{m and n} calculated in step S70. On the other hand, the case of “NO” in step S74 indicates that the additional allocatable amounts _{m and n} calculated in step S72 or S73 cannot cover the additional discharge request amounts _{m and n} calculated in step S70. .

In step S75, the EMS 50 determines the discharge permission amounts _{m and n} to be additionally allocated. In this process, EMS50, the additional discharge demand amount _m calculated in step _S70, the _n, the discharge enable the amount _m to be added _assignment, and _n.

On the other hand, in step S76, the EMS 50 determines the discharge permission amounts _{m and n} to be additionally allocated by a method different from that in step S75. In this process, EMS50, the additional allocatable amount _m calculated in step S72 or _S73, the _n, discharge permission amount _m to be added _assignment, and _n.

  After performing the processing of Step S75 or Step S76, the EMS 50 proceeds to Step S77.

In step S77, the EMS 50 initializes the actual discharge amounts _{m and n} . Thus, the actual discharge amount _{m, n} = 0. After performing the process in step S77, the EMS 50 proceeds to step S78.

In step S78, the EMS 50 determines whether or not the preliminarily dischargeable amount _n > 0. If the EMS 50 determines that the preliminarily dischargeable amount _n > 0 (“YES” in step S78), the process proceeds to step S79. On the other hand, when the EMS 50 determines that the predischargeable amount _n > 0 is not satisfied (“NO” in step S78), the process proceeds to step S80.

In step S79, the EMS 50 updates the available preliminary discharge amount _n . In this process, EMS50 the discharge permission added assignment from the preliminary discharge amount _n of the previous update amount _m, by subtracting _n, updating the pre-dischargeable amount _n.

On the other hand, in step S80, the EMS 50 updates the discharge permission amounts _{L and n} . In this process, the EMS 50 updates the discharge permission amounts _{L and n} by subtracting the discharge permission amounts _{m and n} additionally allocated from the discharge permission amounts _{L and n} before updating.

  After performing the processing in step S79 or S80, the EMS 50 ends the discharge permission amount additional allocation processing (that is, step S66 in FIG. 8) illustrated in FIG.

  FIG. 8 is referred to again. The EMS 50 repeats the processing from steps S64 to S66 for the number of storage batteries n. In this way, the processes from steps S64 to S66 are performed for all the storage batteries n. After performing the processes from steps S64 to S66 for all the storage batteries n, the EMS 50 proceeds to step S67.

In step S67, the EMS 50 issues a discharge instruction to the required number of storage batteries n in order from the storage batteries n having the larger remaining dischargeable amounts _{m and n} among the storage batteries n not additionally allocated. This makes it possible to equalize the remaining amount of stored power. When the discharge from the storage batteries n not additionally allocated is not sufficient, the required number of storage batteries n in the additionally allocated storage batteries n is instructed in order from the storage allowable battery _m, and the remaining storage batteries n are on standby. Make instructions.

  After performing the process of step S67, the EMS 50 ends the discharge control process illustrated in FIG. 8 (that is, step S16 of FIG. 3).

  FIG. 3 is referred to again. In step S13, if the EMS 50 determines that the current time is the end time of the group m (“YES” in step S13), the process proceeds to step S14.

  In step S14, the EMS 50 performs surplus discharge permission amount allocation processing. Here, the “excessive discharge permission amount” is the discharge permission amount allocated in the discharge permission amount allocation process in step S11 shown in FIG. 3 and (if necessary) the discharge permission amount additional allocation process in step S66 shown in FIG. Of these, it indicates a surplus discharge permission amount with respect to the discharge amount actually required for the storage batteries 12, 22, and 32. The details of the surplus discharge permission amount allocation process will be described later.

  After performing the process in step S14, the EMS 50 proceeds to step S15.

In step S15, the EMS 50 initializes the actual discharge amounts _{m and n} . Thus, the actual discharge amount _{m, n} = 0.

  The EMS 50 repeats the process of step S15 for the number of storage batteries n. In this way, the process of step S15 is performed for all the storage batteries n. After performing the process of step S15 for all the storage batteries n, the EMS 50 proceeds to step S16. The processing in step S16 is as described above.

  Hereinafter, the surplus discharge permission amount allocation processing (step S14 shown in FIG. 3) will be described with reference to FIG. The surplus discharge permission amount allocating process shown in FIG. 7 is a process of setting the surplus discharge permission amount to the preliminary dischargeable amount or returning the surplus discharge permission amount to the original group.

In step S50, the EMS 50 determines whether or not the surplus discharge permission amount _{m, n} > 0. As described above, the “excessive discharge permission amount” indicates the surplus discharge permission amount that actually surpasses the discharge amount required for the storage batteries 12, 22, and 32 among the discharge permission amounts allocated in step S11 and the like. It is. If the EMS 50 determines that the surplus discharge permission amount _{m, n} > 0 (“YES” in step S50), the process proceeds to step S51. On the other hand, if the EMS 50 determines that the surplus discharge permission amount _{m, n} > 0 is not satisfied (“NO” in step S50), the process returns to step S50 again and performs the process in step S50 for the next storage battery.

  Note that the case of “YES” in step S50 means that the actual power consumption of the load H can be covered by the discharge permission amount (and the power generated by the solar power generation units 11, 21 and 31) allocated in step S11 and the like. Indicates that it was possible. On the other hand, the case of “NO” in step S50 means that the discharge permission amount (and the power generated by the solar power generation units 11, 21, and 31) allocated in step S11 and the like can cover the actual power consumption of the load H. Indicates that it could not be done.

  In step S51, the EMS 50 determines whether or not the discharge permission amount has been additionally allocated. In this process, the EMS 50 determines whether or not the discharge permission amount additional allocation process shown in FIG. 9 (Step S66 shown in FIG. 8) has been performed. If the EMS 50 determines that the allowable discharge amount has been additionally allocated (“YES” in step S51), the process proceeds to step S54. On the other hand, if the EMS 50 determines that the additional discharge permission amount has not been allocated (“NO” in step S51), the process proceeds to step S52.

  The case of “YES” in step S50 and “YES” in step S51 indicates that there is an additional allocation from another group or the possible preliminary discharge amount, and that the surplus of the discharge permission amount has occurred. I have. On the other hand, the case of “YES” in step S50 and “NO” in step S51 means that the group m, which has not been additionally allocated from another group or the preliminary dischargeable amount, has reached the end time (see FIG. (See step S13 shown in FIG. 3) indicates that surplus has occurred only in the discharge permission amount allocated in step S11.

  In step S52, the EMS 50 determines whether there is an unfinished group. In this process, the EMS 50 determines whether there is an unfinished group, that is, a group whose end time has not yet elapsed at the present time. For example, when the time is divided into a plurality of time zones as in the group 2, the EMS 50 determines whether or not there is a group in which the end time of the last half time zone (24:00 in the case of the group 2) has not yet elapsed. Is determined. If the EMS 50 determines that there is an unfinished group (“YES” in step S52), the process proceeds to step S53. On the other hand, if the EMS 50 determines that there is no unfinished group ("NO" in step S52), the process proceeds to step S57.

In step S53, the EMS 50 adds the surplus discharge permission amounts _{m and n} to the discharge permission amounts _{x and n} of the group x having the highest power purchase unit price among the unfinished groups. After performing the process in step S53, the EMS 50 returns to step S50 again, and performs the process in step S50 for the next storage battery.

  On the other hand, in step S54, the EMS 50 determines whether or not additional allocation has been performed from another group. If the EMS 50 determines that additional allocation has been performed from another group ("YES" in step S54), the process proceeds to step S55. On the other hand, if the EMS 50 determines that no additional allocation has been made from another group ("NO" in step S54), the process proceeds to step S57.

  The case of “YES” in step S54 indicates that additional allocation has been performed from another group (the group L with the lowest unit price) (step S73 shown in FIG. 9). On the other hand, the case of “NO” in step S54 indicates that additional allocation has been performed based on the possible preliminary discharge amount (step S72 shown in FIG. 9).

  In step S55, the EMS 50 determines whether or not the original group has not been completed. In this process, the EMS 50 determines whether or not the group of the additional allocation source (the group L with the lowest purchase price) has not been completed. If the EMS 50 determines that the original group is not completed ("YES" in step S55), the process proceeds to step S56. On the other hand, if the EMS 50 determines that the original group has not been terminated (“NO” in step S55), the process proceeds to step S57.

In step S56, the EMS 50 returns the surplus discharge permission amounts _{m and n} to the original group (the group L with the lowest purchase price). In this process, EMS50 the discharge permission amount before the process _L, the excess discharge allowances _m to _n, by adding the _n, discharge permission amount after the process _L, thereby forming _n.

On the other hand, in step S57, the EMS 50 returns the surplus discharge permission amounts _{m and n} to the preliminary dischargeable amount _n . In this process, the EMS 50 adds the surplus discharge permission amounts _{m and n} to the pre-discharge possible amount _n before the process to obtain the pre-discharge possible amount _n after the process.

  The EMS 50 repeats the processing from step S50 to S57 for the number of storage batteries n. In this way, the processes from steps S50 to S57 are performed for all the storage batteries n. The EMS 50 completes the surplus discharge permission amount allocation process (ie, step S14 in FIG. 7) by performing the processes from steps S50 to S57 for all the storage batteries n, and proceeds to step S15 in FIG. Transition. The processing after step S15 is as described above.

  As described above, the EMS 50 basically sets the maximum allowable discharge amount assigned by the discharge planning control (steps S10 and S11 shown in FIG. 3) performed on the previous day as the upper limit, from the storage battery n (the storage batteries 12, 22, and 32). Perform discharge. Then, it is calculated based on the actual power consumption of the load H (total house load obtained in step S60) and the actual power generated by the solar power generation units 11, 21, and 31 (total PV power generation obtained in step S61). The required amount of discharge from the storage batteries 12, 22 and 32 (the required amount of discharge calculated in step S62) and the permitted discharge amount assigned to the predicted required amount of discharge (steps S34 and S35) Etc.) are corrected.

  Specifically, when the actually required discharge amount from the storage batteries 12, 22, and 32 exceeds the allocated discharge permission amount, an additional allocation process of the discharge permission amount is appropriately performed, so that the system power supply K Power consumption can be reduced, and the electricity rate can be reduced. On the other hand, when the actually required discharge amount from the storage batteries 12, 22, and 32 is smaller than the allocated discharge permission amount, the surplus amount (excess discharge permission amount) is allocated to another time zone, and the storage battery 12 -It is possible to effectively use the stored electric power of 22.32, and to avoid a situation in which the stored electric power of the storage batteries 12, 22.32 is originally used but surplus without being used up. Can be achieved.

As described above, the power supply system 1 according to the present embodiment includes the power storage devices (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the power storage device) that can charge and discharge the power from the system power supply K. Three power storage systems 30 (storage batteries 32)), an EMS 50 (request amount predicting unit) for predicting a required discharge amount, which is a required discharge amount of the power storage device, and An EMS 50 (allocation unit) that allocates a discharge permission amount that is a discharge amount permitted to the device. The EMS 50 (allocation unit) sets a discharge permission time period that is a time period during which the power storage device is permitted to discharge. , The power from the system power supply K is divided into a plurality of groups m for each unit purchase price, and a discharge permission amount is preferentially assigned to the discharge request amount of the group having the high purchase price (step From-flops S20 S22) is intended.
With this configuration, the power storage devices (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system 30 (the storage battery 32) The electricity charge can be reduced by performing the discharge of)).

In the power supply system 1 according to the present embodiment, the power storage devices (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system 30 (the storage battery 32)) can be discharged. EMS50 (possible amount prediction unit) for predicting a dischargeable amount that is a large amount of discharge, the plurality of power storage devices are provided, and the EMS50 (requested amount prediction unit) includes a total of the dischargeable amounts of the power storage device. The required amount of discharge is calculated for each of the power storage devices according to the ratio of the dischargeable amount of each of the power storage devices to the total dischargeable amount, and the EMS 50 (assignment unit) If the dischargeable amount is equal to or more than the required discharge amount of the power storage device, the required discharge amount is set as the permitted discharge amount of the power storage device (steps S32 and S34). That.
With this configuration, the allowable discharge amount is provided to all of the dischargeable power storage devices (first power storage system 10 (storage battery 12), second power storage system 20 (storage battery 22), and third power storage system 30 (storage battery 32)). Can be assigned, so that it is possible to easily cope with a change in the power consumption of the load.

Further, the EMS 50 (allocation unit) determines that the dischargeable amount of the power storage device (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system 30 (the storage battery 32)). When the amount is less than the required discharge amount of the power storage device, the dischargeable amount is set as the discharge permission amount of the power storage device (step S35 and the like).
With this configuration, the discharge permission according to the dischargeable amount of the power storage device (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system 30 (the storage battery 32)). Quantity. More specifically, when the dischargeable amount is less than the required discharge amount, if the required discharge amount is directly assigned as the permitted discharge amount, an amount that cannot be actually supplied is assigned as the permitted discharge amount. Can occur. However, in the present invention, when the dischargeable amount is less than the required discharge amount, instead of setting the required discharge amount as the discharge permitted amount as it is, the dischargeable amount is used as the discharge permitted amount, and such a situation is solved. Can be prevented.

Further, the EMS 50 (possible amount predicting unit) is configured to operate the power storage device (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system 30 (the storage battery 32)) per unit time. Is calculated by multiplying the maximum discharge amount by the total time of the group m, and when the dischargeable amount of the power storage device is equal to or more than the value, the value is set as the dischargeable amount (step S42). It is.
With this configuration, the dischargeable amount can be set according to the total time of the group m. More specifically, it is possible to prevent an amount that cannot be actually supplied from being determined as a dischargeable amount, and thus prevent an amount that cannot be actually supplied from being allocated as a discharge permission amount. it can.

Further, the EMS 50 (allocation unit) preferentially allocates the discharge permission amount to the power storage device having the small dischargeable amount (steps S31 to S37).
With this configuration, the number of power storage devices (first power storage system 10 (storage battery 12), second power storage system 20 (storage battery 22), and third power storage system 30 (storage battery 32)) permitted to be discharged is large. This makes it easy to respond to changes in the power consumption of the load.

In addition, the power storage devices (the first power storage system 10 (the storage battery 12), the second power storage system 20 (the storage battery 22), and the third power storage system) are actually set with the discharge permission amount determined by the EMS 50 (allocation unit) as an upper limit. 30 (storage battery 32)) and a hybrid power conditioner 13, 23, 33 and an EMS 50 (control unit) for controlling the discharge amount from the power storage device according to the discharge amount required for the EMS 50 (allocation unit). If the dischargeable amount is still surplus even if the discharge permission amount is allocated, the surplus amount is stored as a preliminary dischargeable amount, and the EMS 50 (control unit) determines the discharge determined by the EMS50 (allocating unit). If the permitted amount cannot actually cover the amount of discharge required of the power storage device, the additional allocation of the permitted discharge amount is performed with the preliminarily dischargeable amount as an upper limit. Step S23) is intended.
With this configuration, it is possible to correct the difference between the discharge permission amount assigned to the predicted discharge request amount and the actually requested discharge amount.

The first power storage system 10 (storage battery 12), the second power storage system 20 (storage battery 22), and the third power storage system 30 (storage battery 32) according to the present embodiment are one embodiment of a power storage device.
Further, the EMS 50 according to the present embodiment is an embodiment of a request amount prediction unit, an assignment unit, a possible amount prediction unit, and a control unit.

  As described above, the embodiments of the present invention have been described, but the present invention is not limited to the above configuration, and various changes can be made within the scope of the invention described in the claims.

  For example, the power supply system 1 is provided in an apartment house, but is not limited to this. For example, the power supply system 1 may be provided in an office or the like.

  In addition, the power supply system 1 includes the solar power generation units 11, 21, and 31 that generate power using sunlight. However, the power supply system 1 may be a fuel cell, or other natural energy (for example, hydropower). Or wind power). Further, the power supply system 1 does not necessarily have to include the photovoltaic power generation units 11, 21, and 31.

  In the present embodiment, the number of power storage systems is three, but may be any number, for example, one.

  In the present embodiment, the real-time correction control (steps S12 to S16 shown in FIG. 3) is performed on the day, but the real-time correction control is not an essential configuration in the present invention.

REFERENCE SIGNS LIST 1 power supply system 10 first power storage system 12 storage battery 20 second power storage system 22 storage battery 30 third power storage system 32 storage battery 50 EMS

Claims (6)

A power storage device capable of charging and discharging power from the system power supply,
A request amount prediction unit that predicts a discharge request amount that is a discharge amount required for the power storage device,
An allocating unit that allocates a discharge permission amount that is a discharge amount permitted to the power storage device to the predicted discharge request amount,
With
The allocating unit includes:
The discharge permission time period, which is a time period in which the power storage device is allowed to discharge, is divided into a plurality of groups for each unit price of power purchased from the system power supply,
Allocating a discharge permission amount preferentially to the discharge request amount of the group with a high power purchase unit price,
Power supply system. The power storage device includes a possible amount prediction unit that predicts a dischargeable amount that is a discharge amount that can be discharged,
A plurality of the power storage devices are provided,
The request amount prediction unit,
The discharge required amount is calculated for each of the power storage devices according to a ratio of the dischargeable amount of each of the power storage devices to a total dischargeable amount that is a sum of the dischargeable amounts of the power storage devices,
The allocating unit includes:
When the dischargeable amount of the power storage device is equal to or larger than the required discharge amount of the power storage device, the required discharge amount is set to the discharge permitted amount of the power storage device.
The power supply system according to claim 1. The allocating unit includes:
When the dischargeable amount of the power storage device is less than the required discharge amount of the power storage device, the dischargeable amount is set to the discharge permission amount of the power storage device.
The power supply system according to claim 2. The possible amount prediction unit,
Calculate a value obtained by multiplying the maximum discharge amount per unit time of the power storage device by the total time of the group,
When the dischargeable amount of the power storage device is equal to or more than the value, the value is set to the dischargeable amount,
The power supply system according to claim 2. The allocating unit includes:
Preferentially assigning the discharge permission amount to the power storage device having a small dischargeable amount,
The power supply system according to any one of claims 2 to 4. A control unit that controls a discharge amount from the power storage device according to a discharge amount actually required for the power storage device, with the discharge permission amount determined by the allocation unit as an upper limit,
The allocating unit includes:
If the dischargeable amount is still surplus even if the discharge permission amount is assigned, the surplus is stored as a preliminary dischargeable amount,
The control unit includes:
When the discharge permission amount determined by the allocating unit cannot actually cover the discharge amount required for the power storage device, an additional allocation of the discharge permission amount is performed with the preliminary dischargeable amount as an upper limit,
The power supply system according to any one of claims 2 to 5.

Images