JP2021036762A - Power storage device - Google Patents

Abstract

To provide a power storage device and a power management system that can reduce, for a plurality of users, an initial cost paid by each of the users in installing the power storage device.SOLUTION: In a power management system 1, a power storage device 100 capable of supplying power to a plurality of users comprises: a storage battery 104; a plurality of DC/AC conversion units 102A, 102B in which the respective DC/AC conversion units are connected to separate users; and a control unit 107 that independently controls the plurality of DC/AC conversion units. The control unit 107 divides the capacity of the storage battery into a plurality of virtual storage batteries, and manages the remaining capacity of each of the virtual storage batteries based on electric power converted by the respective DC/AC conversion units.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a power storage device and a power management system.

Conventionally, a power management system such as a power storage device in which a distributed power source is connected to a system is known (see, for example, Patent Document 1).

A power management system that uses a power storage device connected to a grid can suppress power purchase during peak hours by discharging the power storage device during peak hours of power demand. By curbing the electricity purchased during peak hours, consumers can reduce their electricity bills.

Japanese Unexamined Patent Publication No. 2011-083089

For example, in a facility such as an apartment house where there are a plurality of consumers, if each consumer installs a power storage device, each consumer can reduce the electricity bill. However, since the initial cost is required to install the power storage device, even if the electricity charge can be reduced, the initial cost may not be recovered in some cases.

An object of the present disclosure made in view of such a point is to provide a plurality of consumers with a power storage device and a power management system capable of reducing the initial cost borne by each customer when installing the power storage device. There is.

The power storage device according to an embodiment of the present disclosure is a power storage device capable of supplying electric power to a plurality of consumers including a first consumer and a second consumer. The power storage device is a control that virtually divides the capacity of the storage battery into a single storage battery and a plurality of virtual storage batteries including the first virtual storage battery for the first consumer and the second virtual storage battery for the second consumer. A unit and a DC / DC charging / discharging unit connected to each of the power lines of the plurality of consumers are provided. The DC / DC charging / discharging unit is described when the control unit executes a process of increasing the remaining capacity of the first virtual storage battery by the first electric energy and decreasing the remaining capacity of the second virtual storage battery by the second electric energy. The storage battery is controlled so as to charge and discharge the amount of electric power corresponding to the difference between the amount of electric power received from the electric energy line of the first consumer and the amount of electric power supplied to the electric energy line of the second consumer.

According to the power storage device and the power management system according to the embodiment of the present disclosure, it is possible to reduce the initial cost borne by each customer when installing the power storage device for a plurality of consumers.

It is a figure which shows the schematic structure of the electric power management system including the power storage device which concerns on 1st Embodiment of this disclosure. It is an image diagram which shows the state which the storage battery of FIG. 1 is virtually divided. It is an image diagram for demonstrating how the storage battery of FIG. 1 is virtually divided and charged / discharged. It is an image diagram of the state of charge / discharge of the virtual storage battery A of FIG. It is an image diagram of the state of charge / discharge of the entire storage battery of FIG. It is a flowchart which shows an example of the operation of the power storage device of FIG. It is a flowchart which shows an example of the operation of the power storage device of FIG. It is a figure which shows an example of the electric power flow at the time of charging and discharging in the power storage device of FIG. It is a figure which shows the schematic structure of the electric power management system which concerns on 2nd Embodiment of this disclosure. It is a figure which shows the schematic structure of the electric power management system which concerns on 3rd Embodiment of this disclosure. It is an image diagram in the case where the electric power generated by the solar power generation device is equally charged by each consumer. It is a figure which shows the schematic structure of the electric power management system which concerns on 4th Embodiment of this disclosure.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[First Embodiment]
The power management system 1 shown in FIG. 1 includes a power storage device 100, a first load 10A, a second load 10B, a first power meter 20A, and a second power meter 20B.

As shown in FIG. 1, in the power storage device 100, the power line to which the consumer A is supplied with power from the system 30 (hereinafter, also referred to as “the power line of the customer A”) and the power line from which the customer B is supplied from the system 30 It is connected to two power lines of the power line (hereinafter, also referred to as "customer B power line"). Note that FIG. 1 shows, as an example, an example in which the power storage device 100 is connected to two power lines, that is, the power line of the consumer A and the power line of the consumer B, but the power storage device 100 has two or more power lines. It may be connected to the power lines of any number of consumers.

In FIG. 1, the solid line connecting each functional block mainly indicates a power line, and the broken line mainly indicates a communication line or a signal line.

The power storage device 100 can independently supply electric power to a plurality of consumers, that is, both the consumer A and the consumer B in the example shown in FIG. Further, the power storage device 100 can charge the storage battery 104 by receiving power from the power line of the consumer A. Similarly, the power storage device 100 can charge the storage battery 104 by receiving power from the power line of the consumer B. Details of the configuration and function of the power storage device 100 will be described later.

The first load 10A is an electric device connected to the power line of the consumer A. The first load 10A can communicate with the power storage device 100, and transmits information such as power consumption to the power storage device 100. Although FIG. 1 shows a configuration in which one first load 10A is connected to the power line of the consumer A, the first load 10A may be two or more.

The second load 10B is an electric device connected to the power line of the consumer B. The second load 10B can communicate with the power storage device 100, and transmits power consumption information and the like to the power storage device 100. Although FIG. 1 shows a configuration in which one second load 10B is connected to the power line of the consumer B, the second load 10B may be two or more.

The first watt hour meter 20A measures the amount of power supplied from the system 30 to the consumer A. The electricity charge of the consumer A is determined based on the measured value of the first watt hour meter 20A.

The second watt hour meter 20B measures the amount of power supplied from the system 30 to the consumer B. The electricity charge of the consumer B is determined based on the measured value of the second watt hour meter 20B.

Subsequently, the details of the configuration and function of the power storage device 100 will be described. The power storage device 100 includes a first current sensor 101A, a second current sensor 101B, a first DC / AC conversion unit 102A, a second DC / AC conversion unit 102B, a DC / DC charging / discharging unit 103, a storage battery 104, and the like. It includes a communication unit 105, a storage unit 106, and a control unit 107.

The first current sensor 101A detects the current flowing between the first DC / AC conversion unit 102A and the power line of the consumer A. The first current sensor 101A transmits the detected current value to the control unit 107. The current value detected by the first current sensor 101A includes information on the direction and the absolute value.

The second current sensor 101B detects the current flowing between the second DC / AC conversion unit 102B and the power line of the consumer B. The second current sensor 101B transmits the detected current value to the control unit 107. The current value detected by the second current sensor 101B includes information on the direction and the absolute value.

The first DC / AC conversion unit 102A converts DC power and AC power in both directions. The first DC / AC conversion unit 102A converts the DC power supplied from the DC / DC charge / discharge unit 103 or the second DC / AC conversion unit 102B into AC power and supplies it to the power line of the consumer A. The first DC / AC conversion unit 102A converts the AC power supplied from the power line of the consumer A into DC power and supplies it to the DC / DC charging / discharging unit 103 or the second DC / AC conversion unit 102B.

The second DC / AC conversion unit 102B converts DC power and AC power in both directions. The second DC / AC conversion unit 102B converts the DC power supplied from the DC / DC charge / discharge unit 103 or the first DC / AC conversion unit 102A into AC power and supplies it to the power line of the consumer B. The second DC / AC conversion unit 102B converts the AC power supplied from the power line of the consumer B into DC power and supplies it to the DC / DC charging / discharging unit 103 or the first DC / AC conversion unit 102A.

The DC / DC charge / discharge unit 103 controls the charge / discharge of the storage battery 104. When charging the storage battery 104, the DC / DC charging / discharging unit 103 boosts or lowers the voltage of the DC power supplied from at least one of the first DC / AC conversion unit 102A and the second DC / AC conversion unit 102B. It is supplied to the storage battery 104 to charge the storage battery 104. When the DC / DC charging / discharging unit 103 discharges the storage battery 104, the DC / DC charging / discharging unit 103 boosts or lowers the DC power discharged by the storage battery 104 to at least one of the first DC / AC conversion unit 102A and the second DC / AC conversion unit 102B. Supply to.

The communication unit 105 is connected to the first load 10A and the second load 10B by wire or wirelessly, and communicates with the first load 10A and the second load 10B by a predetermined communication protocol such as ECHONET Lite (registered trademark). I do. The communication unit 105 acquires power consumption information and the like from, for example, the first load 10A and the second load 10B. Further, when the first load 10A does not have a communication function, the communication unit 105 obtains information on the power consumption of the first load 10A from a current sensor installed so as to detect the current consumption of the first load 10A. You may get it. The same applies when the second load 10B does not have a communication function. At this time, the first load 10A and the second load 10B include all the load devices of each consumer.

The storage unit 106 is configured by using, for example, a semiconductor memory, a magnetic memory, or the like. The storage unit 106 stores various information and programs necessary for the operation of the power storage device 100.

Further, the storage unit 106 independently stores the remaining capacities of the virtual storage battery A and the virtual storage battery B configured by virtually dividing the capacity of the storage battery 104. Hereinafter, the concept of the virtual storage battery will be described with reference to FIG.

In the example shown in FIG. 2, the capacity of the storage battery 104 is virtually divided into a virtual storage battery A and a virtual storage battery B. Here, "virtually" dividing means that instead of physically dividing, what is actually one storage battery is independently divided as if there were multiple separate storage batteries. It means that the charging and discharging of the virtual storage battery are numerically controlled. In the example of FIG. 2, the capacity of one storage battery 104 is virtually divided into four, "virtual storage battery A", "virtual storage battery B", "minimum maintenance capacity", and "secured free capacity" for management. .. The "minimum maintenance capacity" and "secured free capacity" are used to protect the storage battery 104 from over-discharging and over-charging, respectively, and are not actively used for charging and discharging. The control unit 107 virtually divides the capacity of the storage battery 104 and numerically controls it.

FIG. 2 shows an example when the capacity of the storage battery 104 is 20 kWh. Generally, in order to prevent overcharging and overdischarging and extend the life of a storage battery, the remaining capacity does not exceed a predetermined upper limit value (hereinafter, first upper limit value) and a predetermined lower limit value (hereinafter, first upper limit value). It is controlled so as not to fall below 1 lower limit value). In the example shown in FIG. 2, the first upper limit value is 90% and the first lower limit value is 10%. Therefore, the capacity for 2 kWh, which exceeds 90% of the first upper limit value, is secured as the reserved free capacity so as not to be charged any more. Further, the capacity for 2 kWh, which is less than 10% of the first lower limit value, is secured as the minimum maintenance capacity so as not to be discharged any more.

Then, in the example shown in FIG. 2, the capacity that can be substantially used by the storage battery 104 is the remaining 16 kWh. For example, this can be virtually divided into two by 8 kWh each to obtain a virtual storage battery A and a virtual storage battery B. In the present embodiment, it is assumed that the virtual storage battery A is the storage battery for the consumer A and the virtual storage battery B is the storage battery for the consumer B. The ratio of the capacities to be divided into the virtual storage battery A and the virtual storage battery B may be equal, or the ratio may be changed according to the contracted power and the power consumption.

The explanation will be continued by returning to FIG. 1 again.

The control unit 107 includes a processor that controls and manages the entire power storage device 100, including each functional block included in the power storage device 100. The program executed by the processor may be stored in, for example, a memory included in the control unit 107 or may be stored in the storage unit 106.

The control unit 107 acquires the current value flowing between the first DC / AC conversion unit 102A and the power line of the consumer A from the first current sensor 101A. The control unit 107 acquires the current value flowing between the second DC / AC conversion unit 102B and the power line of the consumer B from the second current sensor 101B.

The control unit 107 independently controls the operations of the first DC / AC conversion unit 102A and the second DC / AC conversion unit 102B. Further, the control unit 107 controls the operation of the DC / DC charge / discharge unit 103. The control unit 107 has, for example, the first DC / AC converter 102A, the first DC / AC converter 102A, based on the power consumption information of the first load 10A and the second load 10B acquired via the communication unit 105 and the remaining capacity of the storage battery 104. It controls the operations of the 2DC / AC conversion unit 102B and the DC / DC charging / discharging unit 103. For example, the control unit 107 charges the first DC / AC converter 102A and DC / DC so as to supply power from the capacity of the virtual storage battery A to the first load 10A when the power consumption of the first load 10A is large. The operation of the discharge unit 103 may be controlled.

Further, the control unit 107 may control the operations of the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC charge / discharge unit 103 based on the time zone. For example, the control unit 107 operates the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC charging / discharging unit 103 so as to charge the storage battery 104 at midnight when the electricity charge is low. You may control it. Further, the control unit 107 determines a peak power time zone in which the power consumption of the first load 10A is large from the history of the power consumption information of the first load 10A in the past, and the capacity of the virtual storage battery A in the peak power time zone. The operations of the first DC / AC conversion unit 102A and the DC / DC charging / discharging unit 103 may be controlled so as to supply power to the first load 10A.

The control unit 107 manages the capacity of the storage battery 104 by dividing it into a virtual storage battery A for the consumer A and a virtual storage battery B for the customer B as described above. In the following description, the control unit 107 virtually divides 16 kWh, which is a substantially usable capacity, out of the capacity of 20 kWh of the storage battery 104 into two, and 8 kWh each for the virtual storage battery A and the virtual storage battery B. Capacity will be allocated and managed.

The control unit 107 manages the remaining capacity of the virtual storage battery A based on the power converted by the first DC / AC conversion unit 102A. Further, the control unit 107 manages the remaining capacity of the virtual storage battery B based on the power converted by the second DC / AC conversion unit 102B. The control unit 107 stores and manages the remaining capacity of the virtual storage battery A and the remaining capacity of the virtual storage battery B in the storage unit 106.

In the control unit 107, based on the direction of the current acquired from the first current sensor 101A, either the first DC / AC conversion unit 102A receives power from the power line of the consumer A, or the first DC / AC conversion unit 102A receives power from the customer A. Determine if power has been supplied to the power line. Further, the control unit 107 calculates the amount of electric power received or supplied based on the absolute value of the current value acquired from the first current sensor 101A. The control unit 107 increases or decreases the remaining capacity of the virtual storage battery A based on the direction and the absolute value of the current value acquired from the first current sensor 101A described above.

When the control unit 107 determines that the power line of the consumer A is supplied with 2 kWh of electric power from the first DC / AC conversion unit 102A based on the current value acquired from the first current sensor 101A, for example, the virtual storage battery A Reduce the remaining capacity by 2kWh. At this time, the control unit 107 may calculate the amount of electric power to be reduced from the remaining capacity of the virtual storage battery A in consideration of the discharge efficiency. In the following description, when a specific numerical value of electric energy is used, the discharge efficiency is assumed to be 1.0 for simplification.

When the control unit 107 determines that the first DC / AC conversion unit 102A has received 2 kWh of electric power from the power line of the consumer A based on the current value acquired from the first current sensor 101A, for example, the virtual storage battery A Increase the remaining capacity by 2kWh. At this time, the control unit 107 may calculate the amount of electric power to be increased with respect to the remaining capacity of the virtual storage battery A in consideration of the charging efficiency. In the following description, when a specific numerical value of electric energy is used, the charging efficiency is assumed to be 1.0 for simplification.

Although a specific example of increasing or decreasing the remaining capacity of the virtual storage battery A has been described above, the control unit 107 performs the same process when increasing or decreasing the remaining capacity of the virtual storage battery B.

When the remaining capacity of the virtual storage battery A reaches a predetermined upper limit value (hereinafter, the second upper limit value), the control unit 107 has the remaining capacity of the entire storage battery 104 (remaining capacity of the virtual storage battery A + remaining capacity of the virtual storage battery B +). Even if the minimum maintenance capacity) does not reach the first upper limit of 90% (capacity of virtual storage battery A + capacity of virtual storage battery B + minimum maintenance capacity + secured free capacity = ratio to 100), the virtual storage battery A is supplied. The first DC / AC conversion unit 102A is controlled so as to stop charging. The second upper limit value is, for example, a value at which the capacity (8 kWh) allocated to the virtual storage battery A is 100%. The same applies to the virtual storage battery B.

When the remaining capacity of the virtual storage battery A reaches a predetermined lower limit value (hereinafter, the second lower limit value), the control unit 107 does not reach the first lower limit value of 10% even if the remaining capacity of the entire storage battery 104 does not reach the first lower limit value. , The first DC / AC conversion unit 102A is controlled so as to stop the discharge of the virtual storage battery A. The second lower limit value is, for example, a value at which the capacity (8 kWh) allocated to the virtual storage battery A is 0%. The same applies to the virtual storage battery B.

FIG. 3 shows an image diagram when the remaining capacity of the virtual storage battery A reaches 100%, which is the second upper limit value. In the example shown in FIG. 3, the virtual storage battery B still has a remaining capacity. That is, the storage battery 104 is still physically rechargeable. However, in the state shown in FIG. 3, the control unit 107 controls the first DC / AC conversion unit 102A so that the virtual storage battery A is not charged any more.

FIG. 4 shows an example of the time dependence of the remaining capacity of the virtual storage battery A. In the example shown in FIG. 4, at time t1, the remaining capacity of the virtual storage battery A reaches 100%, which is the second upper limit value. Therefore, the control unit 107 controls the first DC / AC conversion unit 102A so as to stop charging the virtual storage battery A at the time t1.

Further, in the example shown in FIG. 4, at time t2, the remaining capacity of the virtual storage battery A reaches 0%, which is the second lower limit value. Therefore, the control unit 107 controls the first DC / AC conversion unit 102A so as to stop the discharge from the virtual storage battery A at the time t2.

The control unit 107 controls overcharge protection and overdischarge protection for the remaining capacity of the entire storage battery 104. The control unit 107 calculates the remaining capacity of the entire storage battery 104 by adding up the remaining capacity of the virtual storage battery A, the remaining capacity of the virtual storage battery B, and the minimum maintenance capacity. When the remaining capacity of the entire storage battery 104 reaches the first upper limit value (for example, 90%), the control unit 107 stops charging the storage battery 104 with the first DC / AC conversion unit 102A and the second DC / AC conversion unit. It controls the operation of 102B and the DC / DC charging / discharging unit 103. Further, the control unit 107 stops the discharge from the storage battery 104 when the remaining capacity of the entire storage battery 104 reaches the first lower limit value (for example, 10%), so that the first DC / AC conversion unit 102A and the second DC / AC It controls the operation of the conversion unit 102B and the DC / DC charge / discharge unit 103.

FIG. 5 shows an example of time dependence of the remaining capacity of the entire storage battery 104. In the example shown in FIG. 5, at time t3, the remaining capacity of the entire storage battery 104 reaches 90%, which is the first upper limit value. Therefore, at time t3, the control unit 107 stops charging the storage battery 104 for overcharge protection, so that the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC Controls the operation of the charging / discharging unit 103.

An example of the operation of the power storage device 100 according to the first embodiment of the present disclosure will be described with reference to the flowcharts shown in FIGS. 6 and 7.

The control unit 107 acquires a current value from the first current sensor 101A and the second current sensor 101B (step S101).

The control unit 107 updates the remaining capacity of the virtual storage battery A stored in the storage unit 106 based on the current value acquired from the first current sensor 101A (step S102).

The control unit 107 determines whether the remaining capacity of the virtual storage battery A is equal to or greater than the second upper limit value (step S103).

When it is determined that the remaining capacity of the virtual storage battery A is equal to or greater than the second upper limit value (Yes in step S103), the control unit 107 stops charging the virtual storage battery A (step S104) and proceeds to step S105.

When it is determined that the remaining capacity of the virtual storage battery A is not equal to or greater than the second upper limit value (No in step S103), the control unit 107 proceeds to step S105.

The control unit 107 determines whether the remaining capacity of the virtual storage battery A is equal to or less than the second lower limit value (step S105).

When it is determined that the remaining capacity of the virtual storage battery A is equal to or less than the second lower limit value (Yes in step S105), the control unit 107 stops the discharge from the virtual storage battery A (step S106) and proceeds to step S107.

When it is determined that the remaining capacity of the virtual storage battery A is not equal to or less than the second lower limit value (No in step S105), the control unit 107 proceeds to step S107.

The control unit 107 updates the remaining capacity of the virtual storage battery B stored in the storage unit 106 based on the current value acquired from the second current sensor 101B (step S107).

The control unit 107 determines whether the remaining capacity of the virtual storage battery B is equal to or greater than the second upper limit value (step S108).

When it is determined that the remaining capacity of the virtual storage battery B is equal to or greater than the second upper limit value (Yes in step S108), the control unit 107 stops charging the virtual storage battery B (step S109) and proceeds to step S110.

When it is determined that the remaining capacity of the virtual storage battery B is not equal to or greater than the second upper limit value (No in step S108), the control unit 107 proceeds to step S110.

The control unit 107 determines whether the remaining capacity of the virtual storage battery B is equal to or less than the second lower limit value (step S110).

When it is determined that the remaining capacity of the virtual storage battery B is equal to or less than the second lower limit value (Yes in step S110), the control unit 107 stops the discharge from the virtual storage battery B (step S111) and proceeds to step S112.

When it is determined that the remaining capacity of the virtual storage battery B is not equal to or less than the second lower limit value (No in step S110), the control unit 107 proceeds to step S112.

The control unit 107 calculates the remaining capacity of the entire storage battery 104 by adding the remaining capacity of the virtual storage battery A, the remaining capacity of the virtual storage battery B, and the minimum maintenance capacity (step S112).

The control unit 107 determines whether the remaining capacity of the entire storage battery 104 is equal to or greater than the first upper limit value (step S113). Although not shown, in the above determination, when the first upper limit value is reached by current control, the voltage of the storage battery 104 is measured and the error to the first upper limit value is corrected by charging the voltage control. May be good.

When it is determined that the remaining capacity of the entire storage battery 104 is equal to or greater than the first upper limit value (Yes in step S113), the control unit 107 stops charging the storage battery 104 for overcharge protection (step S114). The process proceeds to step S115.

When it is determined that the remaining capacity of the entire storage battery 104 is not equal to or greater than the first upper limit value (No in step S113), the control unit 107 proceeds to step S115.

The control unit 107 determines whether the remaining capacity of the entire storage battery 104 is equal to or less than the first lower limit value (step S115).

When it is determined that the remaining capacity of the entire storage battery 104 is equal to or less than the first lower limit value (Yes in step S115), the control unit 107 stops the discharge from the storage battery 104 for over-discharge protection (step S116). End the operation.

When it is determined that the remaining capacity of the entire storage battery 104 is not equal to or less than the first lower limit value (No in step S115), the control unit 107 ends the operation.

The control unit 107 repeats the operations of steps S101 to S116 at predetermined time intervals.

Subsequently, with reference to FIG. 8, the first DC / AC conversion unit 102A receives 1.0 kWh of power from the power line of the consumer A, and the second DC / AC conversion unit 102B 0 to the power line of the customer B. An example of supplying a power of .7 kWh will be described. For the sake of brevity, the charging efficiency and the discharging efficiency will be described as 1.0.

In this case, the first DC / AC conversion unit 102A converts 1.0 kWh of AC power received from the power line of the consumer A into DC power, and supplies 0.7 kWh of DC power to the second DC / AC conversion unit 102B. Then, 0.3 kWh of DC power is supplied to the DC / DC charging / discharging unit 103.

The second DC / AC conversion unit 102B converts 0.7 kWh of DC power supplied from the first DC / AC conversion unit 102A into AC power and supplies it to the power line of the consumer B.

The DC / DC charging / discharging unit 103 supplies 0.3 kWh supplied from the first DC / AC converter 102A to the storage battery 104 to charge the storage battery 104.

In the above operation, the storage battery 104 is substantially charged by 0.3 kWh, but the control unit 107 increases the remaining capacity of the virtual storage battery A by 1.0 kWh and decreases the remaining capacity of the virtual storage battery B by 0.7 kWh. Execute the process.

In the example shown in FIG. 8, the DC / DC charging / discharging unit 103 only executes a process of charging the difference of 0.3 kWh, and a process of charging 1.0 kWh and then discharging 0.7 kWh. I will not do it. As a result, it is possible to cope with a state in which charging and discharging are required for the same storage battery 104 at the same time, and it is possible to reduce power loss due to the conversion efficiency of the DC / DC charging / discharging unit 103.

When actually managing the charge power amount and the discharge power amount in consideration of the charge efficiency and the discharge efficiency, the temperature of the storage battery 104 and the individual differences between the first current sensor 101A and the second current sensor 101B may be determined. Depending on the factor, a difference is accumulated between the remaining capacity of the management virtual storage battery and the remaining capacity of the actual virtual storage battery. For example, when the storage battery 104 reaches the first upper limit value by charging by current control, the control unit 107 measures the voltage value and corrects it in order to confirm whether it is the first upper limit value, and calculates the correction coefficient from the correction value. Then, it may be applied to the remaining capacity of the virtual storage battery to correct the capacity.

As described above, according to the present embodiment, the control unit 107 divides the capacity of the storage battery 104 into a plurality of virtual storage batteries, and divides the remaining capacities of the virtual storage battery A and the virtual storage battery B into the first DC / AC conversion unit 102A, respectively. And management is performed based on the power converted by the second DC / AC conversion unit 102B. As a result, the power storage device 100 can independently supply electric power to a plurality of consumers as if there were a plurality of storage batteries. Therefore, according to the present embodiment, one power storage device 100 having one storage battery 104 can share electric power with a plurality of consumers, so that each customer needs to install the power storage device individually. It disappears. As a result, one power storage device can be shared by a plurality of consumers, so that the initial cost borne by each customer when installing the power storage device can be reduced. Therefore, the consumer can easily introduce the power storage device as compared with the case where the power storage device is purchased individually.

Further, when a plurality of storage batteries are used by a plurality of consumers one by one, it is expected that the life will be different due to the difference in the usage state. In that case, the replacement time of the storage battery differs for each consumer. For example, if different storage batteries are used for each house in an apartment house, the replacement time of the storage battery varies, which imposes a management burden on the landlord and other managers. growing. However, according to the present embodiment, since one storage battery 104 is actually only virtually divided, the life of each virtual storage battery is the same, and the landlord's management burden when replacing the storage battery Becomes smaller.

(Setting of permitted amount)
In the above description, the control unit 107 has been described as stopping the discharge of the virtual storage battery A when the remaining capacity of the virtual storage battery A reaches the second lower limit value. However, the control unit 107 may set a predetermined permitted amount in advance so that the remaining capacity of the virtual storage battery B can be used for discharging the power line of the consumer A up to the predetermined permitted amount. In this way, when the remaining capacity of the virtual storage battery B is used for discharging the power line of the consumer A, the control unit 107 receives the power borrowed from the virtual storage battery B at the next charging of the virtual storage battery A. Is returned to the virtual storage battery B, and then the information on the remaining capacity in the storage unit 106 is managed so that the virtual storage battery A is charged.

(Control in an emergency)
In an emergency such as an earthquake, the control unit 107 enables discharge even if the remaining capacity of the virtual storage battery falls below the second lower limit value if the remaining capacity of the storage battery 104 does not reach the first lower limit value. It may be controlled to do so.

(Multiple storage batteries)
In the above description, the storage battery 104 in the power storage device 100 has been described as one, but the power storage device 100 may have a plurality of storage batteries. In this case, the control unit 107 may manage each of the plurality of storage batteries by dividing them into virtual storage batteries. For example, if the storage battery A and the storage battery B are provided, the storage battery A is divided into the virtual storage battery A1 and the virtual storage battery B1, the storage battery B is divided into the virtual storage battery A2 and the virtual storage battery B2, and the virtual storage battery A1 and the virtual storage battery A1 are virtual. The capacities of the storage batteries A2 may be added up and managed. The same applies to the virtual storage battery B1 and the virtual storage battery B2. As described above, since the power storage device 100 has a plurality of storage batteries, the other storage batteries can be used while one storage battery is being replaced, so that the storage battery can be continuously stored even when the storage battery needs to be replaced. The device 100 can be used.

[Second Embodiment]
The power management system 2 according to the second embodiment of the present disclosure will be described with reference to FIG. In the present embodiment, the parts different from the first embodiment will be mainly described, and the description of the contents common to or similar to the first embodiment will be omitted.

This embodiment is different from the first embodiment in that the power management system 2 has a power management device 40.

In the present embodiment, the power management device 40 has a part or all of the functions of the control unit 107 in the first embodiment.

The power management device 40 manages the remaining capacity of the virtual storage battery A based on the current value acquired from the first current sensor 101A. Further, the power management device 40 manages the remaining capacity of the virtual storage battery B based on the current value acquired from the second current sensor 101B. The values of the remaining capacities of the virtual storage battery A and the virtual storage battery B may be stored in the storage unit included in the power management device 40, or may be stored in the storage unit in the power storage device 100.

The power management device 40 transmits a command to the control unit 107 to control the operations of the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC charging / discharging unit 103.

As described above, according to the present embodiment, the power management device 40 can execute advanced processing instead of the control unit 107 of the power storage device 100. As a result, the workload of the control unit 107 of the power storage device 100 is reduced, so that the control unit 107 can be configured by using a low-cost CPU. The power management device 40 is in the form of, for example, HEMS (Home Energy Management System) or computer software.

[Third Embodiment]
The power management system 3 according to the third embodiment of the present disclosure will be described with reference to FIG. In the present embodiment, the parts different from the first embodiment will be mainly described, and the description of the contents common to or similar to the first embodiment will be omitted.

The present embodiment is different from the first embodiment in that the power management system 3 has a configuration including a photovoltaic power generation device 50.

The photovoltaic power generation device 50 generates DC power from the energy of sunlight. The photovoltaic power generation device 50 converts the generated DC power into AC power and supplies it to the power line of the consumer A.

The photovoltaic power generation device 50 can communicate with the power storage device 100 by a predetermined communication protocol such as ECHONET Lite (registered trademark), and transmits information such as generated power to the power storage device 100.

The control unit 107 is based on, for example, information on the power consumption of the first load 10A and the second load 10B acquired via the communication unit 105, information on the power generated by the photovoltaic power generation device 50, and the remaining capacity of the storage battery 104. The operation of the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC charge / discharge unit 103 is controlled.

The control unit 107 may use the power generated by the photovoltaic power generation device 50 to charge the virtual storage battery A, or may reverse power flow to the system 30 to sell the power.

When the remaining capacity of the virtual storage battery A reaches the second upper limit value, the control unit 107 stops charging even if the remaining capacity of the virtual storage battery B is vacant, and causes the system 30 to reverse power flow.

(Limited charging source)
In the configuration shown in FIG. 10, the control unit 107 may control the virtual storage battery A and the virtual storage battery B so that the charging sources are completely separated. For example, the control unit 107 controls the virtual storage battery A so that it is charged only from the photovoltaic power generation device 50 and not from the system 30. Further, the control unit 107 controls the virtual storage battery B so as to be charged only from the system 30. By completely separating the power supply for charging in this way, it is possible to make a contract with an electric power company that allows the remaining capacity of the virtual storage battery A to be sold to the system 30.

(Sharing of power generated by solar power generation equipment)
According to the contract between the consumer A and the consumer B, both the virtual storage battery A and the virtual storage battery B are charged by the generated power of the photovoltaic power generation device 50 connected to the power line of the consumer A. Good. In this case, in reality, the power supplied from the solar power generation device 50 is converted into DC power only by the first DC / AC conversion unit 102A and not by the second DC / AC conversion unit 102B, but is not converted by the control unit 107. Is a virtual storage battery A and a virtual storage battery in which the surplus power of the solar power generation device 50 not consumed by the first load 10A is stored in the storage unit 106 as being charged in both the virtual storage battery A and the virtual storage battery B. Update the remaining capacity of B. At this time, even if the control unit 107 manages the information of the storage unit 106 so that the electric power supplied from the photovoltaic power generation device 50 is charged to both the storage battery A and the virtual storage battery B at a ratio of 50%. Alternatively, the information of the storage unit 106 may be managed so that the battery is charged at another predetermined ratio.

(Lending and borrowing free space)
For example, when the control unit 107 manages the information of the storage unit 106 so that the electric power supplied from the photovoltaic power generation device 50 is charged to both the virtual storage battery A and the virtual storage battery B at a ratio of 50%. As shown in (A), the free capacity may differ between the virtual storage battery A and the virtual storage battery B. In the example shown in FIG. 11A, the free capacity of the virtual storage battery A is 2 kWh, and the free capacity of the virtual storage battery B is 5 kWh. In this case, when the virtual storage battery A and the virtual storage battery B are charged by 2 kWh each, the free capacity of the virtual storage battery A becomes zero. In this case, the control unit 107 has the control unit 107 as shown in FIG. 11 (B). Of the free capacity of 3 kWh of the virtual storage battery B, 1.5 kWh may be temporarily lent to the virtual storage battery A (the capacity of the virtual storage battery B is managed as 100% at 6.5 kWh). By lending the free capacity of the virtual storage battery B to the virtual storage battery A in this way, both the virtual storage battery A and the virtual storage battery B can be charged by 3.5 kWh (2 kWh + 1.5 kWh) from the photovoltaic power generation device 50. .. In this case, the control unit 107 controls so that the borrowed portion of 1.5 kWh in the virtual storage battery A is preferentially consumed by the first load 10A. The control unit 107 controls so that when 1.5 kWh of the borrowed portion of the virtual storage battery A is discharged, the capacity of 1.5 kWh is returned to the virtual storage battery B.

Such control can reduce the free capacity of the storage battery 104. Therefore, for example, it becomes easy to secure electric power that can be used in an emergency. The lending and borrowing of the free space may be controlled so that the control unit 107 automatically executes it when the free space exceeds a predetermined threshold value.

[Fourth Embodiment]
The power management system 4 according to the fourth embodiment of the present disclosure will be described with reference to FIG. In the present embodiment, the parts different from the third embodiment will be mainly described, and the description of the contents common to or similar to the third embodiment will be omitted.

In this embodiment, the configuration of the photovoltaic power generation device 60 included in the power management system 4 is different from the configuration of the photovoltaic power generation device 50 in the third embodiment. The photovoltaic power generation device 60 according to the present embodiment supplies the generated DC power to the power storage device 100 as it is. Further, the photovoltaic power generation device 60 supplies the generated DC power between the DC / DC charging / discharging unit 103, the first DC / AC conversion unit 102A, and the second DC / AC conversion unit 102B.

The photovoltaic power generation device 60 can communicate with the power storage device 100 by a predetermined communication protocol such as ECHONET Lite (registered trademark), and transmits information such as generated power to the power storage device 100.

The control unit 107 is based on, for example, information on the power consumption of the first load 10A and the second load 10B acquired via the communication unit 105, information on the power generated by the photovoltaic power generation device 60, and the remaining capacity of the storage battery 104. The operation of the first DC / AC conversion unit 102A, the second DC / AC conversion unit 102B, and the DC / DC charge / discharge unit 103 is controlled.

Based on the information of the generated power acquired from the photovoltaic power generation device 60, the control unit 107 virtually charges the virtual storage battery A and the virtual storage battery B at a ratio of 50% by the generated power of the photovoltaic power generation device 60. The remaining capacities of the storage battery A and the virtual storage battery B are controlled.

Further, for example, when the first DC / AC conversion unit 102A supplies a part of the power generated by the solar power generation device 60 to the first load 10A, the control unit 107 charges the virtual storage battery A with sunlight. The power generated by the power generation device 60 is controlled to be the power obtained by subtracting the power flowing through the first DC / AC conversion unit 102A from the allocated power to the virtual storage battery A. At this time, the control unit 107 controls the first DC / AC conversion unit 102A so that the power generated by the photovoltaic power generation device 60 does not exceed the allocated power to the virtual storage battery A. The same applies to the virtual storage battery B.

Further, for example, when the virtual storage battery B is 100% charged, there is a surplus in the generated power of the photovoltaic power generation device 60. In this case, the control unit 107 supplies the power obtained by subtracting the charging power from the allocation of the generated power of the photovoltaic power generation device 60 to the virtual storage battery A to the first load 10A or to the system 30 by the first DC / AC conversion unit 102A. Reverse power flow. The same applies to the virtual storage battery B.

Although embodiments of the present invention have been described with reference to the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and modifications based on the present disclosure. Therefore, it should be noted that these modifications and modifications are within the scope of the present invention. For example, the functions included in each component and each step can be rearranged so as not to be logically inconsistent, and a plurality of components or steps can be combined or divided into one. Is. Further, although the present invention has been mainly described with respect to the device, the present invention is a method including steps executed by each component of the device, a method executed by a processor included in the device, a program, or a storage medium for recording the program. Can also be realized. It should be understood that these are also included in the scope of the present invention.

1, 2, 3, 4 Power management system 10A 1st load 10B 2nd load 20A 1st watt-hour meter 20B 2nd watt-hour meter 30 system 40 Power management device 50 Solar power generation device 60 Solar power generation device 100 Power storage device 101A 1st current sensor 101B 2nd current sensor 102A 1st DC / AC conversion unit 102B 2nd DC / AC conversion unit 103 DC / DC charge / discharge unit 104 Storage battery 105 Communication unit 106 Storage unit 107 Control unit

Claims (6)

A power storage device capable of supplying electric power to a plurality of consumers including a first consumer and a second consumer.
With a single storage battery
A control unit that virtually divides the capacity of the storage battery into a plurality of virtual storage batteries including the first virtual storage battery for the first consumer and the second virtual storage battery for the second consumer.
A DC / DC charge / discharge unit connected to each of the power lines of the plurality of consumers is provided.
The DC / DC charging / discharging unit is described when the control unit executes a process of increasing the remaining capacity of the first virtual storage battery by the first electric energy and decreasing the remaining capacity of the second virtual storage battery by the second electric energy. The storage battery is controlled so as to charge and discharge the amount of electric energy corresponding to the difference between the amount of electric energy received from the electric energy line of the first consumer and the amount of electric energy supplied to the electric energy line of the second consumer. Power storage device. In the power storage device according to claim 1,
The DC / DC charging / discharging unit controls the storage battery so as not to perform a process of charging the first electric energy and then discharging the second electric energy. In the power storage device according to claim 2,
A first DC / AC converter connected to the DC / DC charging / discharging section and the power line of the first consumer, and a second DC / AC connected to the DC / DC charging / discharging section and the power line of the second consumer. Further provided with a plurality of DC / AC converters including a converter,
The first DC / AC conversion unit converts the first electric energy received from the power line of the first consumer from AC power to DC power, and supplies the second electric energy to the second DC / AC conversion unit. Power storage device. In the power storage device according to claim 3,
The second DC / AC conversion unit is a power storage device that converts the second electric energy supplied from the first DC / AC conversion unit from DC power to AC power and supplies it to the power line of the second consumer. In the power storage device according to any one of claims 1 to 4.
The control unit is a power storage device that controls to lend an arbitrary free capacity of the second virtual storage battery to the first virtual storage battery. The power storage device according to any one of claims 1 to 5.
The control unit is a power storage device that numerically controls the amount of electric power for charging and discharging the first virtual storage battery and the second virtual storage battery.

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