JP7203503B2 - power supply system - Google Patents

Description

TECHNICAL FIELD The present invention relates to technology of a power supply system having a power generation unit capable of generating power using natural energy and a storage battery capable of charging and discharging power.

Conventionally, a technology of a power supply system in which a power generation unit capable of generating power and a storage battery capable of charging/discharging power are provided between a system power supply and a load is known. For example, it is as described in Patent Document 1.

Patent Literature 1 describes a power supply system in which a plurality of units are connected in series to a distribution line that connects a system power supply and a load. The plurality of units includes a solar power generation device and a storage battery (power storage device) that can be charged with electric power from the solar power generation device and a commercial power supply.

In a power supply system such as that described in Patent Document 1, load follow-up operation is performed in which power is output from each unit based on power flowing through a distribution line. In the power supply system, units (storage batteries, etc.) installed in a plurality of houses are connected in series to distribution lines. Power from multiple units can be shared between multiple homes via distribution lines.

Here, in the power supply system described in Patent Document 1, the units capable of supplying power are connected in series to the distribution line. It is also assumed that If the units are connected in parallel, the power cannot be used efficiently, and there is a risk that the economic burden (purchased power) will increase. Specific examples will be described below.

For example, FIG. 7 shows an example of a power supply system 901 applied to a housing complex such as an apartment building. In the power supply system 901, units (power storage systems 910, 920, 930, and 940) are connected in parallel. Specifically, in the example shown in FIG. 7, loads H1, H2, H3, and H4 are connected to four distribution lines L1, L2, L3, and L4 connected in parallel, respectively. Units (storage systems 910, 920, 930, and 940) are connected to the distribution lines L1, L2, L3, and L4, respectively. That is, the power storage systems 910, 920, 930, and 940 are connected in parallel with each other. Each power storage system 910 , 920 , 930 , 940 includes a photovoltaic power generation section 911 , a storage battery 912 , a hybrid power conditioner 913 and a sensor 914 . Each storage battery 912 performs load following operation based on the detection value of the sensor 914 .

In such a power supply system 901, it is assumed that a power demand of 10000 (W) for the load H1, 5000 (W) for the load H2, 8000 (W) for the load H3, and 3000 (W) for the load H4 occurs. do. It is also assumed that each solar power generation unit 911 generates 5000 (W) of power. It is also assumed that the maximum discharge amount of each storage battery 912 is 2000 (W).

Focusing first on the load H4, the load H4 requires power of 3000 (W). In such a case, 3000 (W) of the power generation amount (5000 (W)) of the photovoltaic power generation unit 911 of the power storage system 940 is supplied to the load H4. The remaining 2000 (W) of the power generation amount of the photovoltaic power generation unit 911 is distributed to the system power source S side. In this case, since the power demand of load H4 is satisfied, storage battery 912 of power storage system 940 does not discharge.

Next, focusing on the load H3, the load H3 requires power of 8000 (W). In such a case, the power generation amount (5000 (W)) of the solar power generation unit 911 of the power storage system 930 and the maximum discharge amount (2000 (W)) of the storage battery 912 of the power storage system 930 are supplied to the load H3. Here, the amount of power (7000 (W)) from the power storage system 930 cannot meet the power demand of the load H3. Therefore, 1000 (W) of the 2000 (W) of power that flows from the power storage system 940 to the system power supply S side is supplied to the load H3, and the remaining 1000 (W) further flows to the system power supply S side. .

Next, focusing on the load H2, the load H2 requires power of 5000 (W). In such a case, the power generation amount (5000 (W)) of the photovoltaic power generation unit 911 of the power storage system 920 is supplied to the load H2. In this case, since the power demand of load H2 is satisfied, storage battery 912 of power storage system 920 does not discharge.

Next, focusing on the load H1, the load H1 requires power of 10000 (W). In such a case, the power generation amount (5000 (W)) of the solar power generation unit 911 of the power storage system 910 and the maximum discharge amount (2000 (W)) of the storage battery 912 of the power storage system 910 are supplied to the load H1. Here, the amount of power (7000 (W)) from the power storage system 910 cannot meet the power demand of the load H1. Therefore, 1000 (W) flowing from the power storage system 940 to the system power supply S side is supplied to the load H1, and the shortage of 2000 (W) power is purchased from the system power supply S and supplied to the load H1. be.

As described above, in the example shown in FIG. 7, in the housing complex, some of the storage batteries (storage system 920 and storage battery 912 of the storage system 940) are not discharged (there is power margin). , power is purchased from the system power source S without using the power. In this way, when the power storage systems 910, 920, 930, and 940 are connected in parallel, the power cannot be used efficiently, and there is a risk that the economic burden (power purchase) will increase.

JP 2017-163746 A

The present invention has been made in view of the circumstances as described above, and the problem to be solved is to provide a power supply system capable of suppressing an increase in the economic burden (purchased power).

The problems to be solved by the present invention are as described above, and the means for solving the problems will now be described.

That is, in claim 1, there is provided a power supply system capable of supplying power to a load connected to each of a plurality of electric lines connected in parallel, the power generation unit capable of generating power using natural energy, and a storage battery capable of charging and discharging electric power, an electric storage system connected to each of the electric lines, a purchased power detection unit for detecting the amount of electric power purchased from the power supply, and the power supply detected by the purchased power detection unit a control unit that performs discharge amount adjustment control to increase the discharge amount of the storage battery when the amount of electric power purchased from the and a second mode in which charging and discharging are performed based on instructions from the control unit. By changing the storage battery from the first mode to the second mode and specifying the discharge amount, the discharge amount of the storage battery is increased .

In claim 2, in the discharge amount adjustment control, the control unit determines the number of storage batteries whose discharge amount is to be increased and the discharge amount to be increased based on the amount of electric power detected by the power purchase detection unit. It is.

In claim 3 , in the discharge amount adjustment control, the control unit determines the order of priority based on the remaining amount of the storage battery, and increases the discharge amount with priority given to the storage battery having the highest priority. be.

In claim 4, further comprising a power sale detection unit that detects an amount of power sold from the power storage system to the grid power supply, wherein the control unit detects the power sale in the discharge amount adjustment control. When the unit detects the amount of electric power to be sold to the system power supply, the discharge amount of the storage battery is decreased .

As effects of the present invention, the following effects are obtained.

In claim 1, an increase in economic burden (power purchase) can be suppressed. In addition, an increase in the economic burden (purchased power) can be suppressed by using the mode change of the storage battery.

In claim 2, an increase in economic burden (purchased power) can be efficiently suppressed.

In claim 3 , it is possible to equalize the remaining amount of the storage battery.

In claim 4, unnecessary discharge can be prevented .

1 is a schematic diagram showing a state in which a power supply system according to an embodiment of the present invention is applied to an apartment; FIG. FIG. 2 is a block diagram showing the configuration of a power supply system; 4 is a flowchart showing a process of discharge amount adjustment control; FIG. 4 is a flowchart showing a continuation of FIG. 3; FIG. FIG. 4 is a diagram showing an example of a power supply mode before discharge amount adjustment control is executed; FIG. 5 is a diagram showing an example of a power supply mode when discharge amount adjustment control is executed; FIG. 1 is a block diagram showing the configuration of a conventional power supply system having problems;

Below, the electric power supply system 1 which concerns on one Embodiment of this invention is demonstrated.

The power supply system 1 shown in FIGS. 1 and 2 supplies a load H with power from a system power supply S or power generated using sunlight. A power supply system 1 according to the present embodiment is provided in an apartment complex, and supplies power to a load H (for example, equipment of a plurality of houses R) of the apartment complex.

As shown in FIG. 1, in the present embodiment, an apartment building M having multiple floors is assumed as a housing complex. The power supply system 1 supplies power to the load H of each house R of the condominium M via a plurality of power main lines Lm. The power trunk line Lm is provided in the condominium M so as to extend vertically (vertically). Electric power is supplied to loads H of a plurality of houses R arranged vertically (one row of houses R) by one power main line Lm. FIG. 1 shows an example in which power is supplied to four rows of houses R by four power main lines Lm (first power main line Lm1, second power main line Lm2, third power main line Lm3, and fourth power main line Lm4). showing.

Further, in the condominium M, each row of houses R shares a power storage system (first power storage system 10, second power storage system 20, third power storage system 30, and fourth power storage system 40) described later.

In addition, below, the structure of the said power supply system 1 is demonstrated using FIG. Moreover, below, for convenience, the loads H of the plurality of houses R shown in FIG.

The power supply system 1 is connected to a power path L that supplies power from a system power supply S to a load H. As shown in FIG. The power path L has four power main lines Lm (first power main line Lm1, second power main line Lm2, third power main line Lm3, and fourth power main line Lm4) in the middle (on the downstream side of lead-in portion 50, which will be described later). branches in parallel.

In addition, the power supply system 1 includes a first power storage system 10 capable of supplying power to the load H through each of the first power trunk line Lm1, the second power trunk line Lm2, the third power trunk line Lm3, and the fourth power trunk line Lm4. A second power storage system 20, a third power storage system 30, and a fourth power storage system 40 are connected. The first power storage system 10, the second power storage system 20, the third power storage system 30, and the fourth power storage system 40 are connected to a plurality of houses R (houses R in each row, see FIG. 1) to which electric power is supplied from each power main line Lm. shared respectively by For example, the first power storage system 10 is shared by a plurality of houses R that receive power supply from the first power main line Lm1. The power supply system 1 is capable of interchanging power between houses R that own power storage systems (first power storage system 10, second power storage system 20, third power storage system 30, and fourth power storage system 40).

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 fourth power storage system 40 , a lead-in section 50 and a control section 60 .

The first power storage system 10 stores power generated using sunlight, and supplies or stores power via the first power main line Lm1. The first power storage system 10 includes a solar power generation unit 11 , a storage battery 12 , a hybrid power conditioner 13 and a sensor 14 .

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 photovoltaic power generation unit 11 is installed in a sunny place such as the roof of the apartment building M, for example.

The storage battery 12 is configured to be chargeable with electric power. The storage battery 12 is configured by, for example, a lithium ion battery. Storage battery 12 is connected to solar power generation unit 11 . In this embodiment, the storage battery 12 is assumed to have a maximum charge amount of 2000 (W). Note that the maximum charge amount refers to the maximum amount of power that can be charged by the storage battery 12 per unit time. The storage battery 12 also has a maximum discharge amount (maximum amount of power that the storage battery 12 can discharge per unit time) of 2000 (W). The storage battery 12 can be switched between charge and discharge based on the detection result of the sensor 14, which will be described later.

The hybrid power conditioner 13 appropriately converts electric power (hybrid power conditioner). The hybrid power conditioner 13 is configured to be capable of outputting (supplying) the electric power generated by the solar power generation unit 11 to the storage battery 12 . In addition, the hybrid power conditioner 13 can output (supply) power discharged from the storage battery 12 via the first power main line Lm1, and can output (store) power from the system power source S to the storage battery 12. be done.

The sensor 14 is provided on the first power main line Lm1 (more specifically, immediately upstream (system power source S) side of the connection point between the first power main line Lm1 and the hybrid power conditioner 13). The sensor 14 detects the voltage (supply voltage) and current of electric power (for example, electric power supplied from the system power source S to the load H and the storage battery 12, or reverse power flow to the system power source S) circulating in the place where the sensor 14 is provided. (supply current) is detected. Sensor 14 is connected to hybrid power conditioner 13 and is configured to be capable of outputting a signal regarding the detection result to hybrid power conditioner 13 .

The second power storage system 20 is configured substantially similarly to the first power storage system 10 . Specifically, the solar power generation unit 21, the storage battery 22, the hybrid power conditioner 23, and the sensor 24 of the second power storage system 20 correspond to the solar power generation unit 11, the storage battery 12, the hybrid power conditioner 13, and the sensor 14 of the first power storage system 10, respectively. corresponds to Hybrid power conditioner 23 is connected to second power main line Lm2. Moreover, the sensor 24 is provided on the second power main line Lm2 (more specifically, immediately upstream of the connection point between the second power main line Lm2 and the hybrid power conditioner 23).

The third power storage system 30 is configured substantially similarly to the first power storage system 10 . Specifically, the solar power generation unit 31, the storage battery 32, the hybrid power conditioner 33, and the sensor 34 of the third power storage system 30 correspond to the solar power generation unit 11, the storage battery 12, the hybrid power conditioner 13, and the sensor 14 of the first power storage system 10, respectively. corresponds to Hybrid power conditioner 33 is connected to third power main line Lm3. Further, the sensor 34 is provided on the third power main line Lm3 (more specifically, immediately upstream of the connection point between the third power main line Lm3 and the hybrid power conditioner 33).

The fourth power storage system 40 is configured substantially similarly to the first power storage system 10 . Specifically, the solar power generation unit 41, the storage battery 42, the hybrid power conditioner 43, and the sensor 44 of the fourth power storage system 40 correspond to the solar power generation unit 11, the storage battery 12, the hybrid power conditioner 13, and the sensor 14 of the first power storage system 10, respectively. corresponds to Hybrid power conditioner 43 is connected to fourth power main line Lm4. Further, the sensor 44 is provided on the fourth power main line Lm4 (more specifically, immediately upstream of the connection point between the fourth power main line Lm4 and the hybrid power conditioner 43).

The lead-in part 50 is a part that draws power from the system power source S (power company) to the condominium M. An appropriate switch or the like is provided in the lead-in portion 50 .

The control unit 60 manages information on the first power storage system 10, the second power storage system 20, the third power storage system 30, and the fourth power storage system 40, and controls the operation of the first power storage system 10 and the like (the storage battery 12 and the like). control. The control unit 60 mainly includes an arithmetic processing device such as a CPU, a storage device such as a RAM and a ROM, an input/output device such as a touch panel, and the like. The control unit 60 can control the output of electric power generated by the photovoltaic power generation units 11, 21, 31, 41 and the charging and discharging of the storage batteries 12, 22, 32, 42. In addition, the control unit 60 stores programs and various information in the storage device, and executes operations of the power supply system 1 by reading and processing the programs and various information in the arithmetic processing unit. be able to. Such a control unit 60 is configured by, for example, an EMS (Energy Management System).

The control unit 60 is electrically connected to the hybrid power conditioners 13, 23, and 33. In addition, the control unit 60 controls the upstream side (immediately upstream of the lead-in unit 50) of the parallel branched power main lines (the first power main line Lm1, the second power main line Lm2, the third power main line Lm3, and the fourth power main line Lm4). ), the amount of power sold can be obtained based on the detected value of the system power supply side sensor 61 provided in . The system power supply side sensor 61 detects the voltage (supply voltage) and current (supply current) of power flowing through the provided location. The amount of power sold according to the present embodiment refers to the amount of electricity from the power trunk lines (the first power trunk line Lm1, the second power trunk line Lm2, the third power trunk line Lm3, and the fourth power trunk line Lm4) on the power path L toward the system power supply S side. It refers to the amount of power that is circulating (reverse power flow) through

In addition, the control unit 60 can acquire the power purchase amount based on the detection value of the system power supply side sensor 61 . The purchased power amount according to the present embodiment refers to the amount of power that is distributed (purchased from the system power supply S) in the power path L from the system power supply S side toward the power main line side.

The flow of supplying power to the storage batteries 12, 22, 32, and 42 and the load H in the power supply system 1 configured as described above will be briefly described below.

Power from the system power source S and the photovoltaic power generation units 11, 21, 31, and 41 is supplied to the load H via the power path L. In this way, the residents of the house R can turn on the lights, use the cooking utensils and the air conditioner using the system power supply S and the power from the photovoltaic power generation units 11, 21, 31, and 41.

In this case, if the power consumption of the load H can be covered by the power from the photovoltaic power generation units 11, 21, 31, and 41, it is possible not to use the power from the system power source S. In this way, it is possible to reduce the amount of power purchased from the system power source S and save power charges.

In addition, power from the system power supply S and the solar power generation units 11, 21, 31, 41 can be supplied to the storage batteries 12, 22, 32, 42 during appropriate time periods. The power supplied to the storage batteries 12, 22, 32, 42 can charge the storage batteries 12, 22, 32, 42. The time period during which the storage batteries 12, 22, 32, and 42 are charged can be set arbitrarily. For example, if the time period is set to midnight, the storage batteries 12, 22, 32, and 42 can be charged with low-cost late-night power. Moreover, if the said time slot|zone is set to a daytime time slot|zone, the electric power from photovoltaic power generation part 11*21*31*42 can be charged to the storage battery 12*22*32*42.

Also, the power charged in the storage batteries 12, 22, 32, 42 can be supplied to the load H through the power path L. Specifically, when the storage batteries 12, 22, 32, and 42 are discharged, the discharged power is supplied to the load H through the power path L.

Next, modes of the storage batteries 12, 22, 32, and 42 in the power supply system 1 will be described.

The power supply system 1 has a first mode (eco mode) and a second mode (operating method instruction mode) as modes of the storage batteries 12, 22, 32, and 42, and the like.

The first mode (eco mode) is a mode for the purpose of consuming the electric power generated by the photovoltaic power generation units 11, 21, 31, and 41 at the load H (obtaining an energy saving effect by consuming at the load H). is. When the first mode is set, the storage batteries 12, 22, 32, and 42, when the power from the photovoltaic power generation units 11, 21, 31, and 41 surplus with respect to the power consumption of the load H, the surplus charge power. If the power from the photovoltaic power generation units 11, 21, 31, and 41 still remains surplus even when the storage batteries 12, 22, 32, and 42 are charged to the maximum charge amount, the surplus power flows backward to the system power supply S. be done.

When the first mode is executed, the storage batteries 12, 22, 32, 42 perform load following operation in which the amount of discharge is determined based on the detected values of the sensors 14, 24, 34, 44. For example, if the load H1 consumes power, power is supplied from the system power source S to the load H1 via the first power main line Lm1. The first power storage system 10 detects the power flowing through the first power main line Lm1 with the sensor 14, discharges the storage battery 12 according to the detection value of the sensor 14, and supplies the power to the load H1. At this time, when the photovoltaic power generation unit 11 is generating power, the power generated by the photovoltaic power generation unit 11 is preferentially supplied to the load H<b>1 over discharging of the storage battery 12 . Similarly, when power consumption occurs in loads H2, H3, and H4 other than load H1, storage batteries 22, 32, and 42 perform load follow-up operation.

In addition, the power failure storage battery remaining amount is set in each of the storage batteries 12, 22, 32, and 42. FIG. The power failure storage battery remaining amount is used as a backup power supply for supplying power to the load H in a power failure state (a state in which power from the system power supply S cannot be supplied). It is the amount of electric power secured in the storage batteries 12, 22, 32, 42 in the state of being able to supply power. In the non-power failure state, even if the power consumption of the load H cannot be covered by the power from the photovoltaic power generation units 11, 21, 31, 41, the control unit 60 controls the storage batteries 12, 22, 32, 42. is equal to or less than the remaining battery capacity for power failure, discharge from the storage batteries 12, 22, 32, and 42 is stopped. In this case, the insufficient power is supplied from the system power supply S. In this embodiment, the power outage storage battery residual amounts of the storage batteries 12, 22, 32, and 42 are set to 30% of the storage battery capacity of the storage batteries 12, 22, 32, and 42, respectively. In addition, the value of the power failure storage battery remaining amount is not limited to this, and an appropriate value can be set.

The second mode (operation method instruction mode) is a mode in which it is possible to specifically instruct the operation method (charge/discharge, etc.) of the storage batteries 12, 22, 32, and 42. FIG. Specifically, when a discharge instruction is given, the storage batteries 12, 22, 32, and 42 discharge power by the instructed amount. In addition, when a standby instruction is given, the storage batteries 12, 22, 32, 42 enter a standby state in which charging and discharging are not performed. In addition, when the charging instruction is given, the storage batteries 12, 22, 32, 42 are in a chargeable state, and are charged according to their own charge amount and the surplus power amount of the solar power generation units 11, 21, 31, 41. status or standby status.

In the following, in the power supply system 1 configured as described above, control (hereinafter referred to as will be referred to as "discharge amount adjustment control"). By performing discharge amount adjustment control, the power supply system 1 effectively utilizes the power in the condominium M (in particular, the power charged in the storage batteries 12, 22, 32, and 42), and suppresses an increase in the amount of power purchased. can be done. A specific description will be given below.

In step S101 of FIG. 3, the control unit 60 determines whether the photovoltaic power generation units 11, 21, 31, and 41 are generating power. Specifically, the control unit 60 determines whether or not at least one of the photovoltaic power generation units 11, 21, 31, and 41 is generating power.
When the control unit 60 determines that the photovoltaic power generation units 11, 21, 31, and 41 are not generating power, the process proceeds to step S102.
On the other hand, when the control unit 60 determines that the photovoltaic power generation units 11, 21, 31, and 41 are generating power, the process proceeds to step S103.

In step S102, the control unit 60 changes the mode of all the storage batteries 12, 22, 32, 42 to the first mode (eco mode). As a result, the discharge instruction in the second mode (operating method instruction mode) can be canceled, and the storage batteries 12, 22, 32, 42 can be prevented from being forced to continue discharging. When the processing of step S102 ends, the control unit 60 ends the discharge amount adjustment control.

In step S103, the control unit 60 determines whether or not a certain amount of purchased power is currently being purchased. Specifically, based on the detection value of the system power supply side sensor 61, the control unit 60 determines whether or not power purchase of a predetermined threshold value (for example, 200 (W)) or more is occurring.
If the control unit 60 determines that a certain amount or more of electricity is being purchased at present, the control unit 60 proceeds to step S104.
On the other hand, if the control unit 60 determines that the amount of purchased power is not currently generated above a certain level, the control unit 60 ends the discharge amount adjustment control.

In step S104, the control unit 60 changes the mode of all the storage batteries 12, 22, 32, 42 to the first mode (eco mode). As a result, the discharge instruction in the second mode (operating method instruction mode) can be canceled, and the storage batteries 12, 22, 32, 42 can be prevented from being forced to continue discharging. After completing the process of step S104, the control unit 60 proceeds to step S105.

In step S105, the control unit 60 determines whether or not there are any of the storage batteries 12, 22, 32, 42 that are discharging.
When the control unit 60 determines that there is a discharging storage battery 12, 22, 32, 42, the process proceeds to step S106.
On the other hand, when the control unit 60 determines that there is no discharging storage battery 12, 22, 32, 42, the process proceeds to step S110 (see FIG. 4).

In step S106, the control unit 60 determines whether there is a storage battery 12, 22, 32, 42 that is not discharged at the maximum discharge amount (not at the maximum output) among the discharging storage batteries 12, 22, 32, 42. determine whether or not
If the control unit 60 determines that there is a storage battery 12, 22, 32, 42 that is not discharged at the maximum discharge amount (not at the maximum output), the process proceeds to step S107.
On the other hand, when the control unit 60 determines that there is no storage battery 12, 22, 32, 42 that is not discharged to the maximum discharge amount (not the maximum output), the process proceeds to step S110 (see FIG. 4).

In step S107, the control unit 60 ranks the storage batteries 12, 22, 32, 42 that are discharged (Yes in step S105) and are not at maximum output (Yes in step S106). Specifically, the control unit 60 ranks the storage batteries 12, 22, 32, and 42 so that the storage batteries with the greater remaining capacity have higher priority. Note that the “ranking” in the ranking performed in step S107 means the priority of discharge. In other words, the ranking performed in step S107 is ranking for discharging with priority from the storage batteries 12, 22, 32, 42 with a large remaining amount. After completing the process of step S107, the control unit 60 proceeds to step S108.

In step S108, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 to be discharged according to the amount of electricity purchased and the amount of discharge, and puts that number of storage batteries 12, 22, 32, and 42 in the first mode ( Eco mode) is changed to the second mode (driving method instruction mode) and a discharge instruction is issued.

Specifically, first, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 to be discharged and the amount of discharge according to the purchased power amount. At this time, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 and the amount of discharge required to discharge the same amount of power as the current purchased power amount. The control unit 60 determines the number of storage batteries 12, 22, 32, 42 to be discharged and the amount of discharge, assuming that the storage batteries 12, 22, 32, 42 having the highest priority determined in step S107 are to be discharged preferentially. . For example, even if the storage battery with the highest priority is discharged at the maximum discharge amount (maximum output), the control unit 60 discharges the storage battery with the next highest priority when the current purchase amount is not reached. . In this manner, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 and the amount of discharge required to discharge the same amount of power as the current purchased power amount.

Next, the control unit 60 changes the determined storage batteries 12, 22, 32, 42 from the first mode (eco mode) to the second mode (driving method instruction mode). As a result, the control unit 60 can instruct the operation (especially, the amount of discharge) of the storage batteries 12, 22, 32, 42 changed to the second mode. Further, the control unit 60 instructs the storage batteries 12, 22, 32, 42 changed to the second mode to discharge at the determined discharge amount. As a result, the amount of discharge of the storage batteries 12, 22, 32, and 42 increases by the same power amount as the current purchased power amount. After completing the process of step S108, the control unit 60 proceeds to step S109.

In step S<b>109 , the control unit 60 determines whether or not a certain amount of purchased power is currently being purchased. Specifically, based on the detection value of the system power supply side sensor 61, the control unit 60 determines whether or not power purchases equal to or greater than a predetermined threshold have occurred.
If the control unit 60 determines that a certain amount or more of electricity is being purchased at present, the control unit 60 proceeds to step S110 (see FIG. 4).
On the other hand, when the control unit 60 determines that the power purchase of a certain amount or more is not occurring at present, the control unit 60 proceeds to step S114 (see FIG. 4).

In step S110 (see FIG. 4) after step S105, step S106 or step S109, the control unit 60 determines whether or not there is a stopped (not charged/discharged) storage battery 12, 22, 32, 42. judge.
When the control unit 60 determines that there is a stopped storage battery 12, 22, 32, 42, the process proceeds to step S111.
On the other hand, when the control unit 60 determines that there is no stopped storage battery 12, 22, 32, 42, it ends the discharge amount adjustment control.

In step S111, the control unit 60 determines whether or not the remaining capacity of the stopped storage batteries 12, 22, 32, 42 is equal to or greater than a certain level. Specifically, the control unit 60 determines whether or not the remaining capacity of the stopped storage batteries 12, 22, 32, and 42 is greater than or equal to the remaining capacity of the power failure storage battery.
If the control unit 60 determines that the remaining capacity of the stopped storage batteries 12, 22, 32, 42 is equal to or greater than a certain level, the control unit 60 proceeds to step S112.
On the other hand, when the control unit 60 determines that the remaining amount of the stopped storage batteries 12, 22, 32, and 42 is less than the predetermined amount, the control unit 60 ends the discharge amount adjustment control.

In step S112, the control unit 60 ranks the storage batteries 12, 22, 32, and 42 that are stopped (Yes in step S110) and have a certain amount of remaining power (Yes in step S111). Specifically, the control unit 60 ranks the storage batteries 12, 22, 32, and 42 so that the storage batteries with the greater remaining capacity have higher priority. In addition, the “order” in the ranking performed in step S112 means the order of priority of discharge. Further, when the process proceeds to step S112 after performing the processing of step S107, the processing in step S112 is performed so as to follow the priority determined in step S107 (become lower than the priority determined in step S107). are ranked. As a result, the discharging storage batteries 12, 22, 32, 42 (the storage batteries 12, 22, 32, 42 ranked in step S107) are preferentially discharged. After completing the process of step S112, the control unit 60 proceeds to step S113.

In step S113, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 to be discharged according to the amount of power purchased and the amount of discharge, and switches that number of storage batteries 12, 22, 32, and 42 to the first mode ( Eco mode) is changed to the second mode (driving method instruction mode) and a discharge instruction is issued.

Specifically, first, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 to be discharged and the amount of discharge according to the purchased power amount. At this time, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 and the amount of discharge required to discharge the same amount of power as the current purchased power amount. The control unit 60 determines the number of storage batteries 12, 22, 32, and 42 to be discharged and the amount of discharge, assuming that the storage batteries 12, 22, 32, and 42 having the highest priority determined in step S112 are to be discharged preferentially. . In this manner, the control unit 60 determines the number of storage batteries 12, 22, 32, and 42 and the amount of discharge required to discharge the same amount of power as the current purchased power amount.

Next, the control unit 60 changes the determined storage batteries 12, 22, 32, 42 from the first mode (eco mode) to the second mode (driving method instruction mode). As a result, the control unit 60 can instruct the operation (especially, the amount of discharge) of the storage batteries 12, 22, 32, 42 changed to the second mode. Further, the control unit 60 instructs the storage batteries 12, 22, 32, 42 changed to the second mode to discharge at the determined discharge amount. As a result, the amount of discharge of the storage batteries 12, 22, 32, and 42 increases by the same power amount as the current purchased power amount. After completing the process of step S113, the control unit 60 proceeds to step S114.

In step S114 after moving from step S109 or step S113, the control unit 60 determines whether power selling is currently occurring. Specifically, the control unit 60 determines whether power selling is occurring based on the detection value of the system power supply side sensor 61 .
If the control unit 60 determines that power selling is currently occurring, the control unit 60 proceeds to step S115.
On the other hand, if the control unit 60 determines that power sales are not currently occurring, the control unit 60 ends the discharge amount adjustment control.

In step S115, the control unit 60 issues an instruction to decrease the amount of discharge of the storage batteries 12, 22, 32, 42 with low priority, or sets the storage batteries 12, 22, 32, 42 to the first mode (eco mode). mode). As a result, the control unit 60 can reduce the amount of discharge from the storage batteries 12, 22, 32, 42, thereby reducing the amount of power to be sold. It should be noted that the number of storage batteries 12, 22, 32, 42 for which an instruction is issued or the mode is changed to the first mode in step S115 can be arbitrarily set. Also, the amount of discharge to be reduced in step S115 can be arbitrarily set. After completing the process of step S115, the control unit 60 proceeds to step S116.

In step S116, the control unit 60 determines whether or not there is a storage battery 12, 22, 32, 42 that is currently instructing discharge.
If the control unit 60 determines that there is a storage battery 12, 22, 32, 42 that is instructing discharge at present, the process proceeds to step S114.
On the other hand, if the control unit 60 determines that there is no storage battery 12, 22, 32, 42 that is instructing discharge at present, the control unit 60 ends the discharge amount adjustment control.

By repeatedly performing the discharge amount adjustment control described above, the control unit 60 effectively utilizes the power in the condominium M (in particular, the power charged in the storage batteries 12, 22, 32, and 42), and suppresses an increase in the amount of power purchased. can do.

That is, the control unit 60, when power is being purchased (Yes in step S103) even though the photovoltaic power generation units 11, 21, 31, and 41 are generating power (Yes in step S101), , changes the dischargeable storage battery 12, 22, 32, 42 to the second mode, and issues a discharge instruction to the storage battery 12, 22, 32, 42. At this time, the control unit 60 gives priority to the storage batteries 12, 22, 32, and 42 that have already been discharged (discharged by the load-following operation) and issues a discharge instruction (step S105 to step S105). S108). In addition, even if the discharge amount of the discharging storage battery 12, 22, 32, 42 is specified, if power purchase occurs (Yes in step S109), or if the discharging storage battery 12, 22, 32 If there is no 42 (No in step S105), etc., a discharge instruction is issued to the stopped storage batteries 12, 22, 32, 42 (steps S110 to S113). By causing the storage batteries 12, 22, 32, and 42 to discharge in this manner, the power of the storage batteries 12, 22, 32, and 42 can be effectively used, and the amount of purchased power can be suppressed.

When the control unit 60 issues a discharge instruction to the storage batteries 12, 22, 32, and 42, the storage batteries 12, 22, 32, and 42 are discharged preferentially in descending order of remaining capacity. By this, equalization of the residual amount of the storage battery 12*22*32*42 can be achieved.

Further, if power selling occurs after issuing the discharge instruction to the storage batteries 12, 22, 32, 42 (Yes in step S114), the control unit 60 keeps the storage batteries 12, 22, 32, 42 until the power selling stops. The amount of discharge from 32 and 42 is decreased (steps S114 to S116). As a result, the electric power charged in the storage batteries 12, 22, 32, and 42 can be effectively used for the load H in the condominium M without being sold to the system power source S.

An example of a power supply mode when the discharge amount adjustment control described above is performed will be described below.

FIG. 5 shows the state of the power supply system 1 as a premise. As shown in FIG. 5, there is a power demand of 10000 (W) for load H1, 5000 (W) for load H2, 8000 (W) for load H3, and 3000 (W) for load H4. there is In addition, each of the photovoltaic power generation units 11, 21, 31, and 41 generates power of 5000 (W). It is also assumed that the storage batteries 12, 22, 32, 42 are in the first mode (eco mode).

In this state, 3000 (W) of the power generation amount (5000 (W)) of the solar power generation unit 41 of the fourth power storage system 40 is supplied to the load H4. The remaining 2000 (W) of the power generation amount of the photovoltaic power generation unit 41 is distributed to the system power source S side. In this case, since the power demand of load H4 is satisfied, storage battery 42 of power storage system 40 does not discharge.

Also, the power generation amount (5000 (W)) of the solar power generation unit 31 of the third power storage system 30 and the maximum discharge amount (2000 (W)) of the storage battery 32 of the third power storage system 30 are supplied to the load H3. . Here, the power demand (7000 (W)) from the third power storage system 30 cannot cover the power demand of the load H3. Therefore, 1000 (W) of the 2000 (W) electric power that flows from the fourth power storage system 40 to the system power supply S side is supplied to the load H3, and the remaining 1000 (W) is further supplied to the system power supply S side. circulate.

Also, the power generation amount (5000 (W)) of the photovoltaic power generation unit 21 of the second power storage system 20 is supplied to the load H2. In this case, since the power demand of load H2 is satisfied, storage battery 22 of power storage system 20 does not discharge.

Also, the power generation amount (5000 (W)) of the solar power generation unit 11 of the first power storage system 10 and the maximum discharge amount (2000 (W)) of the storage battery 12 of the first power storage system 10 are supplied to the load H1. . Here, the power demand (7000 (W)) from the first power storage system 10 cannot cover the power demand of the load H1. Therefore, 1000 (W) flowing from the fourth power storage system 40 to the system power source S side is supplied to the load H1, and the shortage of 2000 (W) power is purchased from the system power source S and supplied to the load H1. supplied.

In this way, in the state shown in FIG. 5, although there are storage batteries (storage batteries 22 and 42) that have not been discharged in the power supply system 1 (the power supply system 1 has power margins), the system power supply We purchase electricity from S. As described above, in the power supply system 1 in the state shown in FIG. 5, power cannot be efficiently utilized within the power supply system 1, and an unnecessary economic burden (power purchase) is incurred.

Therefore, the control unit 60 performs the discharge amount adjustment control described above, so that as shown in FIG. can.

Specifically, when the control unit 60 performs the discharge amount adjustment control, discharging is performed to the storage battery (storage batteries 22 and 42) having a higher priority among the stopped storage batteries (the storage battery 42 in FIG. 6). An instruction (in this specific example, a discharge instruction of 2000 (W)) is given. As a result, the storage battery 42 is forcibly discharged. The 2000 (W) electric power discharged from the storage battery 42 and the 2000 (W) electric power from the photovoltaic power generation unit 41 (4000 (W) electric power in total) flow to the system power source S side.

Of the 4000 (W) of power that flows from the power storage system 40 to the system power supply S side, 1000 (W) of power is supplied to the load H3, and the remaining 3000 (W) of power is further supplied to the system power supply S side. circulate.

Also, the power of 3000 W is supplied to the load H1. As a result, the power demand generated by the loads H1, H2, H3, and H4 is satisfied by the power in the power supply system 1 (power from the power storage systems 10, 20, 30, and 40). eliminates the need to purchase In this way, the control unit 60 can reduce the economic burden (power purchase) by performing the discharge amount adjustment control.

As described above, the power supply system 1 according to this embodiment is
Loads (load H1, load H2, load H3 and a power supply system 1 capable of supplying power to a load H4),
Equipped with a power generation unit (solar power generation unit 11, 21, 31, 41) capable of generating power using natural energy, and a storage battery (storage battery 12, 22, 32, 42) capable of charging and discharging electric power, power storage systems (power storage systems 10, 20, 30, 40) connected to each;
a power purchase detection unit (system power supply side sensor 61) that detects the amount of power purchased from the system power supply S;
a control unit 60 that performs discharge amount adjustment control to increase the discharge amount of the storage battery when the amount of electric power purchased from the system power supply S is detected by the power purchase detection unit;
is provided.
By configuring in this way, an increase in economic burden (purchased power) can be suppressed. That is, by increasing the discharge amount of the storage battery, it is possible to compensate for the electric power required by the multiple loads. As a result, it is possible to suppress an increase in the amount of purchased power. In particular, by forcibly increasing the discharge amount of the storage battery by the discharge amount adjustment control, power can be supplied to loads connected to electric lines other than the electric line to which the storage battery is connected.

Further, the control unit 60
In the discharge amount adjustment control, the number of storage batteries whose discharge amount is to be increased and the discharge amount to be increased are determined based on the amount of electric power detected by the power purchase detecting section.
By configuring in this way, it is possible to efficiently suppress an increase in the economic burden (purchased power). That is, by grasping the necessary amount of power based on the amount of power detected by the power purchase detection unit, and determining the number of storage batteries that need to be discharged and the amount of discharge to be increased, wasteful power discharge and discharge amount shortage can be prevented.

Further, the storage battery
A first mode (eco mode) for performing load-following operation in which charging and discharging is performed based on the electric power flowing through the electric circuit to which the storage battery is connected, and a second mode in which charging and discharging are performed based on instructions from the control unit 60. Equipped with a mode (driving method instruction mode),
The control unit 60 is
In the discharge amount adjustment control, the discharge amount of the storage battery is increased by changing the storage battery from the first mode to the second mode and specifying the discharge amount.
By configuring in this way, it is possible to suppress an increase in the economic burden (purchased power) by utilizing the mode change of the storage battery.

Further, the control unit 60
In the discharge amount adjustment control, priority is determined based on the remaining amount of the storage battery, and the storage battery having the higher priority is preferentially increased in discharge amount.
By configuring in this way, it is possible to equalize the remaining amount of the storage battery. That is, by performing discharge with priority from the storage battery with the highest remaining amount, it is possible to equalize the remaining amounts of the plurality of storage batteries. In addition, by this, it is also possible to eliminate the sense of unfairness among a plurality of houses having storage batteries.

In addition, the power supply system 1 is
Further comprising a power sale detection unit (system power supply side sensor 61) that detects the amount of power sold from the power storage system to the system power supply S,
The control unit 60 is
In the discharge amount adjustment control, the discharge amount of the storage battery is decreased when the electric power sale detection unit detects the amount of electric power to be sold to the system power supply S.
By configuring in this way, unnecessary discharge can be prevented. In other words, when surplus power is sold due to fluctuations in the power required by the load (for example, a decrease in the power required by the load), the amount of power discharged from the storage battery is reduced to reduce the amount of power sold. The electricity can be quickly suppressed.

The first power trunk line Lm1, the second power trunk line Lm2, the third power trunk line Lm3, and the fourth power trunk line Lm4 according to the present embodiment are an embodiment of the electric circuit according to the present invention.
Moreover, the photovoltaic power generation units 11, 21, 31, and 41 according to the present embodiment are embodiments of the power generation units according to the present invention.
Further, the system power supply side sensor 61 according to the present embodiment is an embodiment of the purchased power detection section and the sold power detection section according to the present invention.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above configurations, and various modifications are possible within the scope of the invention described in the claims.

For example, although the power supply system 1 is installed in an apartment complex, it is not limited to this, and may be installed in an office or the like.

In addition, in the present embodiment, the power supply system 1 is provided with the photovoltaic power generation units 11, 21, 31, and 41 that generate power using sunlight as power generation units. It is also possible to provide a power generation unit that generates power using wind power).

Also, in the present embodiment, the control unit 60 is configured by, for example, an EMS, but the present invention is not limited to this. For example, the control unit 60 may be various other control devices. Further, instead of the control unit 60, it is also possible to control the power supply system 1 (the above-described discharge amount adjustment control, etc.) by a cloud service.

Also, in the present embodiment, in the discharge amount adjustment control, the priority is determined based on the remaining amount of the storage battery, but the criteria for determining the priority are not limited to this. For example, it can be determined based on the accumulated discharge amount of the storage battery (accumulated discharge amount in a predetermined period). Specifically, a higher priority can be set for a storage battery with a smaller accumulated discharge amount.

REFERENCE SIGNS LIST 1 power supply system 10 power storage system 11 photovoltaic power generation unit 12 storage battery 60 control unit 61 system power supply side sensor H load S system power supply

Claims (4)

A power supply system capable of supplying power to a load connected to each of a plurality of electric lines connected in parallel,
a power storage system that includes a power generation unit that can generate power using natural energy and a storage battery that can charge and discharge power, and that is connected to each of the electric lines;
a power purchase detection unit that detects the amount of power purchased from a grid power supply;
a control unit that performs discharge amount adjustment control to increase the discharge amount of the storage battery when the amount of electric power purchased from the system power supply is detected by the power purchase detection unit;
and
The storage battery
A first mode for performing load following operation in which charging and discharging is performed based on the electric power flowing through the electric circuit to which the storage battery is connected, and a second mode in which charging and discharging are performed based on instructions from the control unit.
The control unit
In the discharge amount adjustment control, the discharge amount of the storage battery is increased by changing the storage battery from the first mode to the second mode and specifying the discharge amount.
power supply system. The control unit
In the discharge amount adjustment control, the number of the storage batteries whose discharge amount is to be increased and the discharge amount to be increased are determined based on the amount of electric power detected by the power purchase detection unit.
The power supply system according to claim 1. The control unit
In the discharge amount adjustment control, priority is determined based on the remaining amount of the storage battery, and the storage battery with the higher priority is prioritized to increase the discharge amount.
The power supply system according to claim 1 or 2. further comprising a power sale detection unit that detects the amount of power sold from the power storage system to the grid power supply,
The control unit
In the discharge amount adjustment control, when the power sale detection unit detects the amount of power to be sold to the system power supply, the discharge amount of the storage battery is reduced.
The power supply system according to any one of claims 1 to 3 .

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