JP2015164378A - Storage battery control device, power supply system, storage battery control method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently operate a plurality of storage battery devices, by using a simple method.SOLUTION: There is provided a storage battery control device 70 for controlling charge/discharge operation of each of a plurality of storage battery devices 50 when the plurality of storage battery devices 50 are connected, as auxiliary power devices, to a power supply path for supplying power from a DC power supply device 20 to a load device. The storage battery control device 70 comprises: a storage battery characteristic determination unit 702 for determining a characteristic during charge/discharge of a storage battery 511 included in each storage battery device of the plurality of storage battery devices 50, on the basis of history information on the charge/discharge of the storage battery; and a control unit 703 for controlling a utilization mode of each of the plurality of storage battery devices 50 on the basis of a result of the determination of the characteristic during charge/discharge of the storage battery 511.

Description

  The present invention relates to a storage battery control device, a power feeding system, a storage battery control method, and a program for controlling charge / discharge operations of a plurality of power storage devices.

  In recent years, in data centers, communication stations, and the like, construction of a DC power supply system that supplies DC power to various load devices such as routers and servers has been promoted. The DC power supply system supplies a DC voltage output from a DC power supply device to a plurality of load devices via a power supply path (power supply line). A power storage device is installed as a power source backup application when an abnormality such as a system fault occurs in the AC power system and a DC voltage cannot be normally output from the DC power supply device to the load device. Alternatively, a power storage device is installed for the purpose of peak cut of received power from the commercial power system at daytime or the like.

  In addition, there exists a related composite storage battery energy management system (refer patent document 1). The composite storage battery energy management system described in Patent Document 1 manages charging / discharging of a plurality of storage batteries according to the purpose of use.

JP 2012-205490 A

When managing the charge / discharge of a plurality of storage batteries according to the purpose of use of the storage battery unit group, the composite storage battery energy management system described in Patent Document 1 is provided with an evaluation function and constraint conditions for optimizing the operation of each storage battery. Set. And based on the set evaluation function, the charging / discharging schedule of each storage battery unit is determined individually.
However, in the composite storage battery energy management system described in Patent Document 1, an attempt is made to manage the charge / discharge schedules of a plurality of storage batteries by calculating a set evaluation function based on the lifetime cost and the constraint conditions of the storage batteries. Therefore, the control is complicated accordingly.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a storage battery control device, a power feeding system, and a storage battery control method capable of efficiently operating a plurality of power storage devices by a simple method. And providing a program.

  The present invention has been made in order to solve the above-described problems. In the storage battery control device of the present invention, a plurality of power storage devices are connected as auxiliary power supply devices to a power supply path for supplying power from a power supply device to a load device. A storage battery control device for controlling the charging / discharging operation of each of the plurality of power storage devices, wherein the characteristics at the time of charging / discharging of the storage battery included in each of the plurality of power storage devices are A storage battery characteristic determination unit that is determined based on history information; and a control unit that controls a usage mode of each of the plurality of power storage devices based on a determination result of characteristics of the storage battery during charging and discharging. And

  Further, in the storage battery control device, the plurality of power storage devices include a plurality of types of power storage devices, and the control unit uses each of the plurality of power storage devices according to the type of the power storage device. It is characterized by controlling.

  Further, in the storage battery control device, a plurality of types of charging methods are mixed in the charging methods of the plurality of power storage devices, and the control unit is configured to charge the charging methods according to usage modes of the plurality of power storage devices. The type is selected.

  Further, in the storage battery control device, the storage battery characteristic determination unit determines a change in characteristics during charging and discharging of the storage battery based on the number of cycles in which charging and discharging are repeated beyond a predetermined discharge depth, and the control unit Sets a power storage device including the storage battery as a power storage device for a first application in which charging and discharging are repeatedly performed beyond a predetermined depth of discharge when the number of cycles of the storage battery is equal to or less than a predetermined reference number. When the number of cycles of the storage battery exceeds a predetermined reference number, the power storage device including the storage battery is normally used to wait for an opportunity to be charged and discharged so as to ensure a predetermined charge amount. It is set as a power storage device for the second use.

  In the storage battery control device, the storage battery characteristic determination unit determines a remaining usable period of the storage battery based on a use period and a lifetime of the storage battery in the power storage device, and the control unit When the remaining usable period of the storage battery is equal to or longer than a predetermined reference period, the power storage apparatus including the storage battery is used as a power storage apparatus for a first application that repeatedly uses charging and discharging beyond a predetermined depth of discharge. When the remaining usable period of the storage battery is less than a predetermined reference period, the power storage device including the storage battery is always charged and discharged so as to ensure a predetermined charge amount Is set as a power storage device for a second application used to stand by.

  Further, in the storage battery control device, the storage battery characteristic determination unit is based on a position where each of the plurality of power storage devices is connected to the power supply path and a position where the load device is connected to the power supply path. A power loss amount when power is supplied from each of the plurality of power storage devices to the load device is determined, and the control unit performs charge / discharge based on the power loss amount determined by the storage battery characteristic determination unit. The power storage device to be selected is selected.

  In the storage battery control device, each of the plurality of power storage devices is provided with a temperature detection unit that detects an ambient temperature around the storage battery included in the power storage device, and the storage battery characteristic determination unit includes Based on the detection result of the ambient temperature around the storage battery detected by the temperature detection unit, it is determined whether the storage battery included in each of the plurality of power storage devices is operable, and the control unit is configured to store the storage battery characteristic. A power storage device to be charged and discharged is selected based on a determination result of the determination unit.

  Further, in the storage battery control device, the control unit sets the output voltage of each of the plurality of power storage devices to a different value, thereby causing the plurality of power storage devices to start discharging to the power feeding path. A priority order is set.

  The power supply system of the present invention supplies power from the power supply device to the load device connected to the power supply path of the power supply device via the power supply path, and a plurality of power storage devices as auxiliary power supply devices in the power supply path. A power supply system connected to the power supply path and supplying power from the solar power generation apparatus to the power supply path, and charging a storage battery included in each of the plurality of power storage devices. A storage battery characteristic determination unit that determines characteristics during discharge based on charge / discharge history information of the storage battery, and a usage mode of each of the plurality of power storage devices based on determination results of characteristics during charge / discharge of the storage battery And a control unit for controlling.

  Further, the storage battery control method of the present invention is configured such that when a plurality of power storage devices are connected as auxiliary power supply devices to a power supply path that supplies power from the power supply device to the load device, the charge / discharge operations of the plurality of power storage devices are performed. A storage battery control method in a storage battery control device to control, a storage battery characteristic determination procedure for determining characteristics at the time of charge and discharge of a storage battery included in each of the plurality of power storage devices based on charge / discharge history information of the storage battery, and And a control procedure for controlling each usage mode of the plurality of power storage devices based on a determination result of characteristics during charging and discharging of the storage battery.

  The program of the present invention controls the charge / discharge operation of each of the plurality of power storage devices when the plurality of power storage devices are connected as auxiliary power supply devices to a power supply path for supplying power from the power supply device to the load device. The storage battery control device includes a storage battery characteristic determination procedure for determining characteristics at the time of charging / discharging of the storage battery included in each of the plurality of power storage devices based on charging / discharging history information of the storage battery, and charging / discharging of the storage battery. And a control procedure for controlling a usage mode of each of the plurality of power storage devices based on a characteristic determination result.

  According to the present invention, a plurality of power storage devices can be efficiently operated by a simple method.

It is a block diagram which shows the structural example of the storage battery control apparatus which concerns on 1st Embodiment of this invention. It is explanatory drawing which shows the example of a setting of the utilization mode based on the cycle number of an electrical storage apparatus. It is explanatory drawing which shows the example which sets a utilization aspect according to the kind of electrical storage apparatus. It is a block diagram which shows the structural example of the storage battery control apparatus 71 which concerns on 2nd Embodiment of this invention. 6 is an explanatory diagram illustrating an example of determining a usable period of the power storage device 51. It is a block diagram which shows the structural example of the storage battery control apparatus 72 which concerns on 3rd Embodiment of this invention. It is a flowchart which shows the procedure of the process of the storage battery control apparatus 72 at the time of the peak cut which reduces the received electric power from a commercial power grid. It is a block diagram which shows the structural example of the storage battery control apparatus 73 which concerns on 4th Embodiment of this invention. It is a flowchart which shows the procedure of the process of the storage battery control apparatus 73 at the time of the peak cut which reduces the received electric power from a commercial power grid. It is a block diagram which shows schematic structure of DC power supply system 1D which concerns on 5th Embodiment of this invention. 2 is a configuration diagram illustrating a configuration of a power conditioner 90. FIG. 4 is a flowchart showing a processing procedure of a storage battery control device 74. It is a block diagram which shows schematic structure of the DC power supply system 1E which concerns on 6th Embodiment of this invention. It is a block diagram which shows schematic structure of AC electric power feeding system 1F which concerns on 7th Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

[First Embodiment]
(Configuration of DC power supply system 1)
FIG. 1 is a configuration diagram illustrating a configuration example of a storage battery control device 70 according to the first embodiment of the present invention. The storage battery control device 70 controls charging / discharging operations of the plurality of power storage devices 50-1, 50-2,..., 50-m in the DC power supply system 1 shown in FIG.
The DC power supply system 1 is an example of a DC power supply system installed in a building such as a data center or a communication station.

1 includes a power receiving facility 10, a DC power supply (REC) 20, a power supply path to a load device, power storage devices 50-1, 50-2,..., 50-m, an energy management device. (EMS) 60 and load devices 100-1, 100-2, ..., 100-n.
In the following description, when the power storage device 50-1 to the power storage device 50-m are collectively referred to as the “power storage device 50”, the load device 100-1 to the load device 100-n is collectively referred to as “ It may be referred to as “load device 100”.

  In the DC power supply system 1, the power storage device 50 may be a power storage device including the same type of storage battery, or a different type of storage battery, for example, a lithium ion battery, a lead battery, a nickel metal hydride battery, or the like. The power storage device may be included. Furthermore, it may be a power storage device including storage batteries having different charging capacities or different charging methods. That is, a plurality of types and capacities of storage batteries and storage batteries of different charging methods may be mixed in the plurality of power storage devices 50. For example, the power storage device 50 includes a storage battery that performs constant current charging, a storage battery that performs constant voltage charging, a storage battery that performs charging by combining constant current charging and constant voltage charging, a storage battery that performs charging at different charging current values, and the like. May be mixed.

  In the storage battery control device 70 according to the first embodiment, when a plurality of power storage devices 50 are connected to the power feeding paths P11 and N11, each of the power storage devices 50 is changed according to the number of cycles of each of the plurality of power storage devices. , Set to either cycle use or backup use.

The cycle usage refers to a usage applied to a usage mode in which charging and discharging are repeatedly performed beyond a predetermined discharge depth. For example, in the DC power supply system 1, power received from the commercial power system 2 is used. The case where it is used for peak cutting for reduction is included. The depth of discharge is a percentage of the capacity taken out of the battery with respect to the actual capacity. For example, in a cycle application, the depth is 80% or more of the rated capacity of the power storage device. Repeat charging and discharging.
On the other hand, the backup application is an application applied to a usage mode in which discharge (use) opportunities are rare and basically most of the operation time is in a charged state. For example, a power storage device for backup use is a power storage device that is normally float-charged and is on standby, is used to discharge when necessary, and is charged and discharged at a deep discharge depth relatively low. For example, the power storage device for backup use is used in the DC power supply system 1 to supply power to the load device 100 during a power failure when power is not supplied from the commercial power system 2 to the DC power supply device 20.

Hereinafter, the configuration of the DC power supply system 1 shown in FIG. 1 will be described in detail.
The power receiving facility 10 includes a circuit breaker (CB) 11, a transformer 12, and a protective relay 13. The protective relay 13 includes, for example, an overcurrent relay, a ground fault relay, an undervoltage relay (all not shown) and the like, and when these relays detect an abnormal state according to each detection condition, The signal is sent to the circuit breaker 11 to open the circuit breaker 11.
For example, the overcurrent relay opens the circuit breaker 11 when it detects that an overcurrent has flowed through the circuit, and the ground fault relay breaks the circuit breaker when it detects that a ground fault has occurred in the circuit or equipment. 11 is opened, and the undervoltage relay opens the circuit breaker 11 when it is detected that commercial power cannot be received from the commercial power system 2 due to a power failure or accident.

  The transformer 12 steps down the high-voltage AC voltage (for example, three-phase AC 6600 V) supplied from the commercial power system 2 to a predetermined low-voltage AC voltage (for example, three-phase AC 400 V), and supplies this low-voltage AC voltage to the DC power supply device 20. Supply. The DC power supply device 20 is a rectifier that converts commercial AC power into DC power, and converts the low-voltage AC voltage input from the transformer 12 into a DC voltage having a predetermined voltage. The DC power supply device 20 includes an AC / DC converter. The AC / DC converter converts an AC 400V AC voltage input from the transformer 12 into, for example, a DC 380V DC voltage. The DC 380V DC voltage is converted into The power is output to power supply paths P11 and N11 that are power supply buses.

  A plurality of power storage devices 50-1 to 50-m including a storage battery are connected to the power supply paths P11 and N11. A plurality of load devices 100-1 to 100-n are connected to the power feeding paths P11 and N11. The load device 100 is an ICT device such as a DC home appliance, an LED lighting device, an air conditioner, a personal computer (PC), or a server.

The energy management device (EMS) 60 manages the operating state of each unit in the DC power supply system 1 and monitors the power consumption in each load device.
The energy management device 60 acquires information on the operation states of the power receiving facility 10, the DC power supply device 20, and the power storage device 50. For example, the energy management device 60 collects information on the power output from the DC power supply device 20 to the power feeding paths P11 and N11 and the power output from the power storage device 50 to the power feeding paths P11 and N11.

  Further, when monitoring the power consumption and the operation state of the load device 100, the energy management device 60 collects information on the power consumption and the operation state of all the load devices 100 or the main load devices 100. Further, the energy management device 60 controls the operating state of the load device 100 when performing peak cut of load power in the load device 100. In addition, the energy management device 60 communicates with the storage battery control device 70 to store information on power output from the DC power supply device 20 to the power supply paths P11 and N11, information on power consumption in the load device 100, and the like. 70 is notified. In addition, the energy management device 60 sends a command signal to the storage battery control device 70 to control the operation of the storage battery control device 70.

  The power storage device 50 includes a storage battery (battery) 511 that is a secondary battery that accumulates and discharges charges, a cycle number detection unit 512, and a bidirectional DC / DC converter 513. The storage battery 511 is a secondary battery such as a lithium ion battery, a lead battery, or a nickel metal hydride battery.

The DC / DC converter 513 is a bidirectional DC / DC converter, and is a power conversion unit that converts DC power discharged from the storage battery 511 into DC power linked to the power feeding paths P11 and N11. That is, the DC / DC converter 513 converts the DC power input from the storage battery 511 into DC power linked to the power supply paths P12 and N12 and supplies the DC power. In this case, the DC / DC converter 513 detects the voltage of the power feeding paths P11 and N11, and adjusts the output voltage based on the detection result of this voltage, whereby the power storage device 50 is connected to the power feeding paths P12 and N12. To be connected.
Further, the DC / DC converter 513 converts the DC power input from the power supply paths P11 and N11 when the storage battery 511 is charged, and stores the electric charge in the storage battery 511 by the converted DC power.
When the electric charge is stored in the storage battery 511, the DC / DC converter 513 performs constant current charging, constant voltage charging, or constant current charging and constant voltage charging according to the type of the storage battery 511, the charging capacity, and the charging state. Switch between and to charge.

The cycle number detection unit 512 counts a charge / discharge operation of a predetermined depth or more (for example, 60% to 80% or more) in the storage battery 511 as one cycle, and “cycle” indicates how many cycles of charge / discharge have been performed in the storage battery 511. Detect number. The cycle number detection unit 512 notifies the storage battery control device 70 of the detected “cycle number” information, and the storage battery control device 70 transmits the information of the “cycle number” received from the cycle number detection unit 512 to the power storage device DB ( Database) 710. The information on “number of cycles 713” stored in the power storage device DB 710 includes information on the number of cycles for each power storage device 50. The information on “number of cycles 713” is referred to by the storage battery characteristic determination unit 702. .
In general, the storage battery 511 has a cycle life, and this cycle life is repeatedly charged / discharged under a specified charge / discharge condition in the secondary battery, for example, 60% (or 80%) of the initial value. It is defined by the number of charge / discharge cycles until the capacity is reduced to For example, the cycle life of the storage battery 511 is about 4000 times.

The storage battery control device 70 includes a storage battery information collection unit 701, a storage battery characteristic determination unit 702, a control unit 703, and a power storage device DB 710.
The power storage device DB 710 stores power storage device information 711 for each power storage device 50. In this power storage device information 711, information on storage battery characteristics 712 indicating the characteristics of the storage battery 511 in each power storage device 50 and information on the number of cycles 713 of charge / discharge performed in each power storage device 50 are stored.
The information on the storage battery characteristics 712 includes information such as the charge / discharge capacity and the lifetime (for example, 10 years) in addition to the information on the type of the storage battery 511 and the cycle life 721. Furthermore, the information of the storage battery characteristics 712 includes “data of change characteristics of the remaining rate with respect to the nominal capacity” with respect to the number of cycles, as shown in FIG.
In addition, since the information of the cycle life 721 included in the information of the storage battery characteristic 712 is used in the first embodiment, it is explicitly shown. In other embodiments, the information of the storage battery characteristic 712 is also included in the information of the storage battery characteristic 712. It is included.

The storage battery information collection unit 701 communicates with the power storage device 50 and collects information including the operation state of the power storage device 50 and information on the number of charge / discharge cycles in the power storage device 50.
The storage battery characteristic determination unit 702 charges / discharges each of the power storage devices 50 based on the information on the number of cycles 713 of the storage battery 511 collected by the storage battery information collection unit 701 and the information on the cycle life 721 of the storage battery 511. Determine changes in characteristics. For example, the storage battery characteristic determination unit 702 determines the rate of decrease in the discharge capacity of the storage battery 511.

For example, the storage battery characteristic determination unit 702 performs charge / discharge characteristics for the storage batteries 511 included in each of the power storage devices 50 based on data of change characteristics of “remaining rate with respect to the nominal capacity” with respect to the number of cycles shown in FIG. It is determined whether there is any change. For example, the storage battery characteristic determination unit 702 predetermines 2000 times as the reference cycle number when the upper limit number of times (hereinafter referred to as “cycle life”) when used for cycle applications and repeated charge and discharge is 4000 times. Keep it. By using the reference number of cycles, it is determined whether or not the number of times of repeated charge and discharge actually used for cycle applications (hereinafter referred to as “cycle number”) exceeds the reference number of cycles, thereby changing the charge / discharge characteristics. It is determined whether or not there is.
When the power storage device 50 includes different types of storage batteries 511, the storage battery characteristic determination unit 702 is based on the cycle life according to the type of the storage battery 511 and the reference cycle number set according to the type of the storage battery 511. Then, it is determined whether there is a change in charge / discharge characteristics.

Control unit 703 controls the usage mode of power storage device 50 based on the determination result of the charge / discharge characteristic determined by storage battery characteristic determination unit 702.
For example, FIG. 2B shows a setting example of the usage mode based on the number of cycles. In FIG. 2B, in order to make the explanation easy to understand, it is assumed that all of the power storage devices 50-1 to 50-m have the same cycle life (4000 cycles), and the reference cycle number is 2000 times. It is said.
As shown in FIG. 2B, the power storage device 50-1, the power storage device 50-3, and the power storage device 50-m that have been executed fewer than 2000 cycles are used as power storage devices for cycle use. The power storage device 50-2 that is set and executed more than 2000 times is set as a power storage device for backup use.

Then, the power storage device 50-3 with the smallest number of cycles is set as the “first power storage device” with the highest priority, and the power storage device 50-m with the next lowest number of cycles is set as the “second power storage device”. Set as "Device". In the same manner, the power storage devices having the third and lower priorities are set in order.
For example, when discharging from the power storage device 50 for cycle use to the power feeding paths P11 and N11, first, discharging is started from the power storage device 50-3 having the first priority to the power feeding paths P11 and N11. When the amount of discharge is insufficient with only the power storage device 50-3, the storage battery control device 70 then starts discharging from the power storage device 50-3 with the second highest priority to the power feeding paths P11 and N11. The same applies to the power storage devices 50 with the third or lower priority.
When the power storage device 50 includes different types of storage batteries 511, the storage battery characteristic determination unit 702 is based on the cycle life according to the type of the storage battery 511 and the reference cycle number set according to the type of the storage battery 511. To set the priority.

Whether the power storage device 50 is set as a power storage device for cycle use or a power storage device for backup use is different between the output voltage of the power storage device for cycle use and the output voltage of the power storage device for backup use. It can be set by providing.
For example, the output voltage of the power storage device 50 for cycle use is set to be several percent higher than the output voltage for backup use. The adjustment of the output voltage in the power storage device 50 is performed by the DC / DC converter 513 based on a command signal from the control unit 703 in the storage battery control device 70.

That is, in the power storage device 50 for cycle use, the output voltage of the DC / DC converter 513 is set to be several percent higher than the output voltage for backup use when discharging electric charges. As a result, when discharge is performed from the power storage device 50 to the power supply paths P11 and N11, the discharge is performed first from the power storage device for cycle use.
In addition, when there are a plurality of cycle-use power storage devices 50, depending on the priority order, by setting each output voltage to a different value, which of the cycle-use power storage devices 50 has priority. Priority can be set to determine whether or not to discharge.

In addition, when the charge accumulated in the cycle-use power storage device 50 is insufficient or exhausted after the cycle-use power storage device 50 starts discharging to the power-feed paths P11 and N11, the backup-use power storage device 50 feeds the power-feed route. P11 and N11 can be discharged.
Thereby, in the case of performing a peak cut to reduce the received power from the commercial power system 2, the storage battery control device 70 operates the power storage device 50 for cycle use preferentially and does not discharge the power storage device for backup use. Can be made to wait.

As described above, the storage battery control device 70 according to the first embodiment has a usage mode (use) in which the power storage device 50 with a small number of cycles and high charge / discharge efficiency is used as the power storage device for cycle use based on the history information for each power storage device 50. It is possible to set the usage mode of the power storage device 50 having a large number of cycles and relatively low charge / discharge efficiency as a power storage device for backup use. Thereby, it can operate | move efficiently according to the use according to the characteristic of the some storage battery by the above simple methods.
For this reason, in the DC power supply system 1, it is possible to reduce the overall power cost. Further, the storage battery control device 70 can manage the change in the charge / discharge characteristics of the power storage device 50 based on the number of cycles, and can determine the change in the characteristics of the power storage device 50 by a simple and realistic method.

Note that the usage mode of the power storage device 50 can be set according to the type of the power storage device 50. For example, FIG. 3 is an explanatory diagram illustrating an example in which the usage mode is set according to the type of the power storage device 50. FIG. 3A shows an example of the main battery type, performance, and cost of the storage battery 511 used in the power storage device 50 (reference: “Current Status and Initiatives of Storage Battery Technology”, Resources Energy Agency, February 2009).
In the example shown in FIG. 3A, a lead battery is inexpensive and has a long cycle life (4500 times), but has a feature that charge / discharge efficiency (87%) is lower than other batteries.
Nickel metal hydride batteries are relatively inexpensive and have a charge / discharge efficiency (90%) higher than that of lead batteries, but have a short cycle life.
In addition, the lithium ion battery has extremely high charge / discharge energy efficiency (95%) and can be rapidly charged / discharged, but is characterized by high cost and weakness to overcharge / overdischarge.

Therefore, as shown in FIG. 3B, an inexpensive lead battery having a long cycle life is used for the power storage device 50 for cycle use. And about this lead battery, for example, it uses as a storage battery for cycle use until the number of cycles reaches 4000 times, and is used as a storage battery for backup use when the number of cycles exceeds 4000 times. In addition, when charging this lead battery, perform rapid charging, and as a charging method. A constant current charging method (or a constant current constant voltage charging method) is used.
Further, since the nickel metal hydride battery is somewhat expensive and has a short cycle life, for example, the nickel metal hydride battery is used as a storage battery for backup purposes. As a method for charging the nickel-metal hydride battery, constant voltage float charging is used.
The constant voltage float charging is a charging method in which the storage battery is always kept in a fully charged state.

Moreover, although a lithium ion battery is expensive, it has a relatively long cycle life (3500 times) and a very high charge / discharge energy efficiency (95%), so it is used as a storage battery for cycle applications. And about a lithium ion battery, it uses as a storage battery for cycle use, for example, until the number of cycles reaches 3000 times, and is used as a storage battery for backup purposes when the number of cycles exceeds 3000 times.
Although this lithium ion battery is charged by rapid charging, the lithium ion battery is vulnerable to overcharging, so when charging, for example, using both constant current charging and constant voltage charging, the charging state of the lithium ion battery Charge while monitoring.

In the example shown in FIG. 3B, when the lead battery and the lithium ion battery are set as storage batteries for cycle use, the priority order of the power storage device including the lead battery is set to lithium by considering the cost of the storage battery. It is set higher than a power storage device including an ion battery.
In the case where priority is set with an emphasis on the charge / discharge efficiency of the storage battery, the priority of the power storage device including the lithium ion battery is set higher than that of the power storage device including the lead battery.

  When supplying power to the load device 100 from a plurality of power storage devices 50 for cycle use, the storage battery control device 70 predicts a change in the amount of load power demand in the power feeding system in correspondence with the position in the system, It is also possible to preferentially select the power storage device 50 at a position where the demand amount is expected to increase and cause the power storage device 50 to discharge. An example in which the power storage device 50 at a position where the demand amount is expected to increase is preferentially selected and discharged will be described later.

Furthermore, when power is supplied to the load device 100 from a plurality of power storage devices 50 for cycle use, the storage battery control device 70 includes the cost per cycle when the power storage device 50 is used for cycle use as a selection condition. Thus, the low-cost power storage device 50 may be preferentially selected.
For example, if the cost calculation is performed in the simplest form, the cost per cycle can be calculated by the following formula.
Cost per cycle = initial cost / cycle life,
The storage battery control device 70 can select a desired power storage device so as to charge and discharge in order from the power storage device 50 having the lowest cost per cycle.

[Second Embodiment]
Next, as a second embodiment, an example will be described in which the charge / discharge mode of each power storage device is switched according to each available period (life) of the plurality of power storage devices.

FIG. 4 is a configuration diagram showing a configuration example of the storage battery control device 71 according to the second embodiment of the present invention. The storage battery control device 71 controls charging / discharging operations of the plurality of power storage devices 51-1, 51-2,..., 51-m in the DC power supply system 1A shown in FIG.
In the following description, the power storage devices 51-1, 51-2, ..., 51-m may be collectively referred to as "power storage device 51".

The storage battery control device 71 shown in FIG. 4 differs from the storage battery control device 70 shown in FIG. 1 in that an available period determination unit 704 is provided in the storage battery characteristic determination unit 702. Further, the difference is that the information of the cycle number 713 shown in FIG.
In addition, the power storage device 51 shown in FIG. 4 is different from the power storage device 50 shown in FIG. 1 in that the cycle number detection unit 512 shown in FIG. 1 is deleted and a usage period detection unit 512A and a mode control unit 514 are newly added. Different points are provided.
In addition, since the information of the lifetime 722 included in the information of the storage battery characteristic 712 is used in the second embodiment, it is explicitly shown, and is also included in the storage battery characteristic 712 in other embodiments. It is what
Other configurations are the same as those of the storage battery control device 70 and the power storage device 50 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.
Note that power storage devices 51-1 to 51-m indicate power storage devices having the same configuration, but the type, charge capacity, and charging method of the storage battery 511 may be different.

In the above configuration, the usage period detection unit 512A in the power storage device 51 measures the usage period (for example, days, months, and years) after starting the operation of the power storage device 51 in each power storage device 51, This storage period information is notified to the storage battery control device 71. The storage battery control device 71 stores information on the usage period received from the power storage device 51 in the power storage device DB 710 as information on the usage period 714.
Moreover, the mode control part 514 switches the charge mode at the time of charging the storage battery 511 mentioned later.

In this storage battery control device 71, the storage battery characteristic determination unit 702 uses the available period determination unit 704 based on the information on the use period 714 of each storage battery 511 in the plurality of power storage devices 51 and the information on the life period 722. Then, the remaining usable period (life) of each power storage device 51 is determined.
Control unit 703 switches the charge / discharge mode of each power storage device 51 in accordance with the remaining available period of each of the plurality of power storage devices 51.
That is, as a mode for charging / discharging the power storage device 51, a first charge / discharge mode in which the charge / discharge amount in one charge / discharge cycle is relatively large, and a second charge / discharge amount in the one charge / discharge cycle are relatively small. There is a charge / discharge mode, and the storage battery control device 71 switches the charge / discharge mode in the power storage device 51 according to the remaining available period.

The first charge / discharge mode is applied to the power storage device 51 for cycle use in which the charge / discharge amount in one charge cycle is relatively large. For example, in the first charge / discharge mode, charge / discharge is performed at a discharge depth of 60% (or 80%) or more. The first charge / discharge mode can be applied when the charge period and the discharge period are repeated relatively frequently.
On the other hand, the second charge / discharge mode is applied to the power storage device 51 for backup use in which the charge / discharge amount in one charge cycle is relatively small, and the predetermined charge amount is maintained by sequentially switching between the charge period and the discharge period.
That is, the power storage device 51 that is charged and discharged in the first charge / discharge mode is used as the power storage device 51 for the cycle application (first use) described in the first embodiment, and is charged and discharged in the second charge / discharge mode. The power storage device 51 to be used is used as the power storage device 51 for the backup use (second use) described in the first embodiment.

(Determination of available period)
As described above, in the storage battery control device 71, the usable period determination unit 704 in the storage battery characteristic determination unit 702 includes the remaining usable period for the storage batteries 511 included in each of the power storage devices 51-1 to 51-m, that is, Determine remaining life. When determining the remaining usable period of the power storage device 51, the available period of each power storage device 51 is determined based on the information on the lifetime period 722 and the information on the usage period 714 of the power storage device 51.
For example, as shown in FIG. 5A, in a storage battery 511 having a lifetime of 10 years, if the current usage period (use period) is 4 years, the remaining available period is determined to be 6 years. To do.

  Then, for example, the control unit 703 sets the reference period as a determination criterion to 5 years, and charges the power storage device 51 in which the remaining usable period is estimated to be 5 years or longer in the first charge / discharge mode. The power storage device 51 is controlled so as to be discharged, and the power storage device 51 is controlled so as to be charged / discharged in the second charge / discharge mode for the power storage device 51 whose remaining usable period is estimated to be 5 years or less. To do.

For example, as illustrated in FIG. 5B, the storage battery control device 71 includes a power storage device 51-1, a power storage device 51-3, and a power storage device 51-m that have a remaining usable period longer than the reference period of five years. Is set as the power storage device in the first charge / discharge mode, and the power storage device 51-2 having a remaining usable period shorter than five years is set as the power storage device in the second charge / discharge mode. Further, the storage battery control device 71 sets the power storage device 51-1 having the longest available period as the power storage device having the “first priority”, and, for example, in the order of the remaining usable periods, for example, the power storage device 51- m is set to “second priority”, and power storage device 51-3 is set to “third priority”.
When the power storage device 51 includes different types of storage batteries 511, the storage battery characteristic determination unit 702 includes a usable period (life) according to the type of the storage battery 511 and a reference period set according to the type of the storage battery 511. Based on, the charge / discharge mode and priority are set.

Whether or not charging / discharging is performed in the first charging / discharging mode or charging / discharging in the second charging / discharging mode in the power storage device 51 is controlled by a mode control unit 514 that controls the charging / discharging mode in the power storage device 51. Is done. Selection of the charge / discharge mode in the mode control unit 514 is performed based on a command signal from the control unit 703 of the storage battery control device 71.
Whether the power storage device 51 performs the discharge in the first charge / discharge mode or the second charge / discharge mode determines whether the output voltage output from the power storage device in the first charge / discharge mode is the second charge / discharge. It can be set by adjusting the output voltage output from the power storage device in the mode.
For example, the output voltage output from the power storage device 51 in the first charge / discharge mode is set to be several percent higher than the output voltage output from the power storage device 51 in the second charge / discharge mode.

That is, in the first charging / discharging mode, the output voltage of the DC / DC converter 513 is adjusted to be higher than the voltage of the power feeding paths P11 and N11, so that the power storage device 51 rapidly adjusts the power feeding paths P11 and N11. It can be controlled to discharge.
Further, when the storage battery 511 is charged by the DC / DC converter 513, the storage battery 511 is set by increasing the charging voltage supplied from the DC / DC converter 513 to the storage battery 511 or by increasing the charging current of the storage battery 511. 511 can be charged quickly.
On the other hand, in the second charge / discharge mode, the output voltage of the DC / DC converter 513 is adjusted to the same level as the voltages of the power supply paths P11 and N11, so that the power storage device 51 can supply power to the power supply paths P11 and N11. Can be discharged slowly. Further, when the storage battery 511 is charged by the DC / DC converter 513, the storage battery 511 is set by setting the charging voltage supplied from the DC / DC converter 513 to the storage battery 511 lower or by reducing the charging current of the storage battery 511. 511 can be slowly charged.

  And, for example, when performing a peak cut to reduce the amount of demand power in response to a request for limiting the amount of received power from an electric power company, that is, to reduce the received power from the commercial power system 2 When the discharge control of the power storage device 51 is performed for the purpose, the storage battery control device 71 causes the power supply paths P11 and N11 to discharge from the power storage device 50 in the first discharge mode. In this case, the storage battery control device 71 first starts discharging from the power storage device 51-1 having the first priority to the power feeding paths P11 and N11. When the amount of discharge is insufficient with only the power storage device 51-1, the storage battery control device 71 starts discharging from the second highest power storage device 51-m having the next highest priority to the power feeding paths P11 and N11. The same applies to the power storage devices 51 with the third or lower priority.

  Thus, in the storage battery control device 71 of the second embodiment, when a plurality of power storage devices 51 are connected to the power feeding paths P11 and N11, according to each remaining available period (life) of the power storage device 51. By switching and using the charge / discharge mode, the plurality of power storage devices 51 can be efficiently operated.

  In addition, although 2nd Embodiment demonstrated the example which sets 1st charging / discharging mode and 2nd charging / discharging mode according to the remaining available period of the electrical storage apparatus 51, in 1st Embodiment, the number of cycles The first charge / discharge mode may be applied to the cycle-use power storage device selected based on the above, and the second charge / discharge mode may be applied to the backup-use power storage device.

[Third Embodiment]
Next, as a third embodiment of the present invention, an example in which the power storage device 50 is selected so that the amount of power loss in the power feeding path is reduced when power is supplied from the power storage device 50 to the load device 100 will be described.

FIG. 6 is a configuration diagram illustrating a configuration example of the storage battery control device 72 according to the third embodiment of the present invention. The storage battery control device 72 controls charging / discharging operations of the plurality of power storage devices 50-1, 50-2,..., 50-m in the DC power supply system 1B shown in FIG.
The storage battery control device 72 shown in FIG. 6 differs from the storage battery control device 70 shown in FIG. 1 in that a power supply path loss calculation unit 705 is newly provided in the storage battery characteristic determination unit 702.
Further, the information in the power storage device DB 710 is different in that the power supply path system information 731 and the connection position information 732 between the power storage device 50 and the load device 100 are included.
Other configurations are the same as those of the storage battery control device 70 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

In the power supply path system information 731 stored in the power storage device DB 710, system information of the power supply path connected to the DC power supply apparatus 20, branch information of the power supply path (wiring path information), bus lines and branches of the power supply path Information on the wiring length of each distribution line constituting the line, the type and diameter of the distribution line, and the conductor resistance (for example, Ω / m) is included.
In addition, the connection position information 732 includes information on the connection position of the power storage device 50 and the load device 100 on the power supply path. The connection position information 732 includes information on the connection position of the power storage device 50 and the load device 100 on the power supply path, information on the charge / discharge capacity of each power storage device 50, and information on the load capacity of each load device 100. include.

In the storage battery control device 72 configured as described above, the power supply path loss calculation unit 705 stores power for the purpose of reducing the power received from the commercial power grid 2 when performing peak cut of the received power in response to a request from the power company, for example. When discharging control of the device 50 is performed, the amount of power loss on the power supply path when power is supplied from each of the power storage devices 50 for cycle use to the load device 100 via the power supply path is calculated.
In other words, the power supply path loss calculation unit 705 includes position information where each of the cycle-use power storage devices 50 is connected to the power supply path system, position information where the load device 100 is connected to the power supply path system, and the power storage apparatus 50. The amount of power loss on the power supply path is calculated with reference to the wiring length of the power supply path from the power supply device to the load device 100 and the information on the conductor resistance of the distribution lines in the power supply path.

When there are a large number of load devices 100, power supply path loss calculation unit 705 selects a predetermined number of load devices as the main load devices in descending order of load capacity, and for each of power storage devices 50 for each cycle, You may make it calculate the electric power loss amount in the electric power feeding path | route between the load apparatuses 100. FIG.
Then, based on the information on the power loss amount on the power supply path calculated by the power supply path loss calculation unit 705, the control unit 703 stores the power supplied to the load device 100 so that the power loss amount is reduced. The device 50 is selected.

Hereinafter, the storage battery control process by the storage battery control device 72 will be described with reference to FIG. FIG. 7 is a flowchart showing a processing procedure of the storage battery control device 72 at the time of peak cut for reducing the amount of received power from the commercial power system.
First, the storage battery control device 72 determines whether or not a peak cut signal instructing to limit the received power from the commercial power system 2 is received from the energy management device (EMS) 60 (step S110).
And in the determination process of step S110, when it determines with having received the peak cut signal (step S110: Yes), the storage battery control apparatus 72 makes the storage battery characteristic determination part 702 to the number of charge / discharge cycles of each storage battery 511. Based on this, the power storage device 50 for cycle use is selected (step S120).

  Subsequently, the storage battery control device 72 calculates the amount of power loss in the power supply path to the load device 100 for each of the selected power storage devices 50 for cycle use by the power supply path loss calculation unit 705 (step S130). When there are a large number of load devices 100, a predetermined number of load devices are selected as the main load devices 100 in descending order of load capacity, and the power supply path loss calculation unit 705 is configured for each power storage device 50 for each cycle use. The amount of power loss in the power supply path with the main load device 100 is calculated.

Subsequently, the storage battery control device 72 compares the calculation results of the power loss amount in the power supply path to the load device 100 for each of the selected cycle-use power storage devices 50. Then, the power storage device 50 that minimizes the amount of power loss is selected (step S140).
Note that the number of power storage devices 50 selected to perform discharge is determined according to the amount of power to perform peak cut and the discharge capacity of power storage device 50, and there are a plurality of power storage devices 50 to be selected. In some cases, the storage battery control device 72 selects the power storage device 50 in order from the smallest power loss amount.
Then, the storage battery control device 72 starts discharging from the power storage device 50 selected in step S140 to the power feeding paths P11 and N11 (step S150). And after performing the process of this step S150, the storage battery control apparatus 72 finishes this storage battery control process.

  Thus, in the storage battery control device 72 of the third embodiment, the power storage device 50 can be selected in consideration of the amount of power loss that occurs in the power supply path from the power storage device 50 to the load device 100.

[Fourth Embodiment]
Next, as the fourth embodiment, an example in which the power storage device to be operated is selected in consideration of the ambient temperature around the storage battery 511 in the power storage device 52 will be described.
FIG. 8 is a configuration diagram showing a configuration example of the storage battery control device 73 according to the fourth embodiment of the present invention. The storage battery control device 73 controls charging / discharging operations of the plurality of power storage devices 52-1, 52-2,..., 52-m in the DC power supply system 1C shown in FIG.
In the following description, the power storage devices 52-1, 52-2,..., 52-m may be collectively referred to as “power storage device 52”.
The storage battery control device 73 shown in FIG. 8 is different from the storage battery control device 70 shown in FIG. 1 in that the temperature characteristic determination unit 706 is provided in the storage battery characteristic determination unit 702 and the temperature detection unit is provided for each of the power storage devices 52. The difference from the provision of 515 is in terms of configuration. Further, the difference is that temperature characteristic data 723 of the storage battery 511 in each power storage device 52 is stored in the power storage device DB 710. Other configurations are the same as those of the storage battery control device 70 and the power storage device 50 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

The temperature characteristic data 723 stored in the power storage device DB 710 stores information on the usable temperature range of the storage battery 511 in each power storage device 52. For example, the upper limit temperature Tmax of the ambient temperature around the storage battery 511, the lower limit temperature Tmin, and the value (%) of the charge / discharge capacity at each temperature are stored. Of this temperature characteristic data 723, the lower limit temperature Tmin is particularly important.
This is because, for example, when the ambient temperature around the storage battery 511 is 0 ° C. or lower, the discharge capacity of the power storage device 52 starts to rapidly decrease, and when it is −15 ° C. or lower, it is difficult to use the power storage device 52 stably. It is because it becomes.

  Therefore, a temperature detection unit 515 is provided in the power storage device 52, and the ambient temperature around the storage battery 511 is detected by the temperature detection unit 515. The power storage device 52 notifies the storage battery control device 73 of information on the detected value of the ambient temperature around the storage battery 511. The storage battery control device 73 refers to the temperature characteristic data 723 stored in the power storage device DB 710 based on the ambient temperature of the storage battery 511 received from the power storage device 52 by the temperature characteristic determination unit 706 in the storage battery characteristic determination unit 702. It is determined whether or not the power storage device 52 including the storage battery 511 is operable.

Hereinafter, the process of the storage battery control device 72 will be described with reference to FIG. FIG. 9 is a flowchart showing a processing procedure of the storage battery control device 73 at the time of peak cut for reducing the received power from the commercial power system 2.
First, the storage battery control device 73 determines whether or not a peak cut signal instructing to limit the received power from the commercial power system 2 is received from the energy management device (EMS) 60 (step S210).
And when it determines with having received the peak cut signal in the determination process of step S210 (step S210: Yes), the storage battery characteristic determination part 702 is based on the cycle number of the charging / discharging of the storage battery 511 in each electrical storage apparatus 52. Thus, the power storage device 52 for cycle use is selected (step S220).

Subsequently, the storage battery control device 73 determines whether or not the ambient temperature around the storage battery 511 is within the usable temperature range in each of the power storage devices 52 selected in step S220, and the storage battery 511 can be used. A power storage device 52 is selected (step S230). That is, the storage battery control device 73 refers to the temperature characteristic data 723 stored in the power storage device DB 710 based on the information on the ambient temperature around the storage battery 511 by the temperature characteristic determination unit 706, and determines the power storage device 52 that can be operated. select.
Then, the storage battery control device 72 starts discharging from the power storage device 52 selected in step S230 to the power feeding paths P11 and N11 (step S240). And after performing the process of this step S240, the storage battery control apparatus 73 ends the process of this storage battery control.

  As described above, in the storage battery control device 73 of the fourth embodiment, the power storage device 52 that is operated based on the past charge / discharge cycle number of the power storage device 52 and the ambient temperature around the storage battery 511 in the power storage device 52. Can be selected.

[Fifth Embodiment]
Next, as a fifth embodiment of the present invention, an example in which the storage battery control device of the present invention is applied to a DC power supply system including a photovoltaic power generation device (PV) will be described.
FIG. 10 is a configuration diagram showing a schematic configuration of a DC power feeding system 1D according to the fifth embodiment of the present invention.
In the DC power supply system 1D shown in FIG. 10, the storage battery control device 74 controls the charge / discharge operations of the plurality of power storage devices 50-1, 50-2,.

Compared with the DC power supply system 1 shown in FIG. 1, the DC power supply system 1D shown in FIG. 10 has a plurality of photovoltaic power generation devices (PV) 80-1, 80-2 on the power supply paths P11 and N11. The difference is that 80-p is connected via a power conditioner (Power Conditioning Subsystem) 90. In addition, the case where only one photovoltaic power generation device (PV) is installed may be sufficient.
Further, the storage battery control device 74 is different from the storage battery control device 70 shown in FIG. 1 in that a surplus power calculation unit 707 is newly provided. Other configurations are the same as those of the DC power supply system 1 and the storage battery control device 70 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.
In the following description, the solar power generation devices (PV) 80-1, 80-2, ..., 80-p may be collectively referred to as "solar power generation device 80".

FIG. 11 is a configuration diagram illustrating a configuration example of a power conditioner (sometimes simply referred to as “PCS”) 90 of the solar power generation device 80.
As shown in FIG. 11, the PCS 90 includes a power generation amount control unit 91, a grid interconnection control unit 92, and a DC / DC converter 93.

In order to extract the maximum power from the solar power generation device 80, the power generation amount control unit 91 has an operating point (maximum) that maximizes the output of the solar cell array 81 in the IV (current-voltage) characteristics of the solar cell array 81. Power point). In the solar cell array 81, the maximum power point is shifted depending on the voltage actually required by the connected load. Since the IV characteristic changes depending on the solar radiation intensity, the module temperature, the state, etc., in order to obtain the maximum power, the optimum voltage or current must be automatically followed. Therefore, the power generation amount control unit 91 controls the solar cell array 81 to operate at the maximum power point.
In addition, the power generation amount control unit 91 notifies the energy management device 60 of information on the power that can be output from the solar power generation device 80.

  In addition, the grid interconnection control unit 92 detects the voltages of the power feeding paths P11 and N11 serving as power feeding buses, and adjusts the output voltage of the DC / DC converter 93 based on the detection result. For example, the grid connection control unit 92 detects the voltages of the power supply paths P11 and N11 in a state where a DC voltage is output from the DC power supply device 20 to the power supply paths P11 and N11, and the DC is based on the detection result. By adjusting the output voltage of the DC / DC converter 93, control is performed so that the power output from the PCS 90 can be fed to the power feeding paths P12 and N12. The DC / DC converter 93 is, for example, a boost converter for boosting the output voltage of the solar power generation device 80 and supplying power to the power feeding paths P11 and N11.

  Returning to FIG. 10, the energy management device 60 collects information on the amount of power output from the DC power supply device 20 to the power feeding paths P <b> 11 and N <b> 11, that is, information on the commercial power amount 61 received from the commercial power grid 2. The energy management device 60 collects information on the PV power generation amount 62 from the photovoltaic power generation device (PV) 80 and also collects information on the load power amount 63 of the load device 100. The energy management device (EMS) 60 notifies the storage battery control device 74 of the information on the commercial power amount 61, the information on the PV power generation amount 62, and the information on the load power amount 63.

The surplus power calculation unit 707 receives information on the PV power generation amount 62 in the solar power generation device 80 from the energy management device (EMS) 60 and detects a fluctuation in the power generation amount in the solar power generation device 80. Further, the surplus power calculation unit 707 receives information on the load power amount (power consumption amount) 63 in the load device 100 from the energy management device (EMS) 60 and detects a change in the load power amount in the load device 100.
Then, the surplus power calculation unit 707 is based on the information on the commercial power amount 61 supplied from the DC power supply device 20 to the power feeding paths P11 and N11 and the information on the PV power generation amount 62 output from the solar power generation device 80. The surplus power amount that changes in accordance with the fluctuation of the load power amount 63 in the load device 100 is calculated.

  When the surplus power amount calculated by the surplus power calculation unit 707 has a margin and the power storage device 50 can be charged, the control unit 703 first selects a cycle application from among the plurality of power storage devices 50. The power storage device 50 is selected based on the priority (see FIG. 2B), and the selected power storage device 50 for cycle use is charged with surplus power. Then, after all of the cycle-use power storage device 50 is charged, if the surplus power has a margin, the backup-use power storage device 50 is subsequently charged.

Hereinafter, the storage battery control process by the storage battery control device 74 will be described with reference to FIG. FIG. 12 is a flowchart showing a processing procedure of the storage battery control device 74.
In the example shown in FIG. 12, there is surplus power for supplying charging power from the solar power generation device 80 to the power storage device 50 in a state where power is supplied from the solar power generation device 80 to the load device 100. This is an example. In addition, the storage battery characteristic determination unit 702 is an example in which a cycle use, a power storage device, and a backup use power storage device are preset for each of the power storage devices 50.

First, the storage battery control device 74 compares the power output from the solar power generation device 80 with the power consumption of the load device 100 by the surplus power calculation unit 707, and the power output from the solar power generation device 80. Thus, it is determined whether or not there is surplus power sufficient to charge the power storage device 50 (step S310).
And in the determination process of step S310, when it determines with there being surplus electric power which charges the electrical storage apparatus 50 from the solar power generation device 80 (step S310: Yes), the storage battery control apparatus 74 is from the solar power generation apparatus 80. Charging the power storage device 50 for cycle use is started (step S320).
When charging the cycle-use power storage device 50, when there are a plurality of cycle-use power storage devices, the storage battery control device 74 charges in order from the power storage device with the highest priority (see FIG. 2B). Do.

Subsequently, the storage battery control device 74 determines whether or not all of the cycle-use power storage devices 50 are fully charged (step S330).
And in the determination process of step S330, when it determines with not all the electrical storage apparatuses 50 for cycle use having been fully charged (step S330: No), the storage battery control apparatus 74 returns to the process of step S310, and solar Charging from the photovoltaic device 80 to the power storage device 50 for cycle use is continued.

On the other hand, in the determination process in step S330, when it is determined that all of the cycle-use power storage devices 50 are fully charged (step S330: Yes), the storage battery control device 74 continues to the solar power generation device 80. Starts charging the power storage device 50 for backup use (step S340).
In step S340, after starting the charging of the backup power storage device 50 from the solar power generation device 80, when the backup power storage device 50 is fully charged, the storage battery control device 74 supplies the power storage device 50 to the power storage device 50. The charging process ends.

  Thus, in the DC power supply system 1D according to the fifth embodiment, power can be supplied to the load device 100 and the power storage device 50 by the solar power generation device (PV) 80, and the plurality of power storage devices 50 can be connected by a simple method. It can be operated efficiently.

In addition, when selecting the power storage device 50 to be charged from the solar power generation device 80, the storage battery control device 74 can use another selection method in addition to the method of selecting the power storage device according to the priority order.
For example, the storage battery control device 74 is similar to the storage battery control device 72 of the third embodiment in that the power storage device reduces the amount of power loss in the power supply path when the charging current flows from the solar power generation device 80 to the power storage device 50. Can be selected.
Moreover, the storage battery control device 74 can also select the power storage device 52 to be charged based on the ambient temperature of the storage battery 511 in the power storage device 50, similarly to the storage battery control device 73 of the fourth embodiment.

[Sixth Embodiment]
Next, as a sixth embodiment of the present invention, the load power of the load device 100 and the power generation power of the solar power generation device 80 are predicted, and the power storage device located near the load device 100 where demand is expected to increase. An example in which 50 is preferentially selected and charged will be described.
FIG. 13 is a configuration diagram showing a schematic configuration of a DC power supply system 1E according to the sixth embodiment of the present invention.
In the DC power supply system 1E shown in FIG. 13, the storage battery control device 74 controls the charge / discharge operations of the plurality of power storage devices 50-1, 50-2,.

In the DC power supply system 1E shown in FIG. 13, the storage battery control device 75 is newly provided with a PV power generation amount prediction unit 708 and a load power prediction unit 709 as compared with the storage battery control device 74 shown in FIG. The point is different. Another difference is that the surplus power calculation unit 707 shown in FIG. 10 is replaced with a surplus power prediction unit 707A.
Further, the difference is that the information of the power generation amount history 741 and the information of the load history 742 are stored in the power storage device DB 710. Other configurations are the same as those of the DC power supply system 1D and the storage battery control device 74 shown in FIG. For this reason, the same code | symbol is attached | subjected to the same component and the overlapping description is abbreviate | omitted.

The power generation amount history 741 in the power storage device DB 710 is information in which information on the PV power generation amount 62 of the solar power generation device 80 is stored together with the weather information 64. This power generation amount history 741 is information that is received from the energy management device (EMS) 60 and stores information on the PV power generation amount 62 together with the weather information 64 at the time of reception. For example, the power generation amount history 741 is information stored in units of 10 minutes to 1 hour.
The weather information 64 is information received from the weather information distribution service company through the Internet, for example.
In addition, the load history 742 is received from the energy management device (EMS) 60 and stored in units of 10 minutes to 1 hour, for example, the load power amount of the entire DC power supply system 1E and the load power amount of each load device 100. Information.

The PV power generation amount prediction unit 708 in the storage battery control device 75 acquires information on the power generation amount history 741 of the solar power generation device 80 and refers to the weather information 64, and after 24 hours from 0 hours every predetermined time interval. A predicted power generation amount curve (not shown) that is a predicted value of the subsequent power generation amount is calculated and output to the surplus power prediction unit 707A.
The load power prediction unit 709 obtains load history information from the load history 742, and calculates a predicted load amount curve (not shown) that is a predicted value of power consumption after 0 hours to 24 hours after every predetermined time interval. . The predicted load amount curve is related to the power usage amount of the entire DC power supply system 1E, and is related to the power usage amount of each load device 100.

The surplus power prediction unit 707A acquires the predicted power generation amount curve from the PV power generation amount prediction unit 708, acquires the predicted load amount curve from the load power prediction unit 709, and can be supplied from the solar power generation device 80 to the power storage device 50. Predict the amount.
Then, the control unit 703 has a higher priority from the plurality of power storage devices 50 based on the surplus power amount predicted by the surplus power prediction unit 707A, from among the suitable power storage devices 50, for example, the cycle-use power storage devices 50. A power storage device is selected and charged.
Further, for example, the load power prediction unit 709 predicts a change in demand for load power in the power feeding system in correspondence with the position of the load device 100 in the system, and the control unit 703 is a load that is expected to increase in demand. The power storage device 50 located near the device 100 can be preferentially selected and charged.

  As described above, in the DC power supply system 1E and the storage battery control device 75 according to the sixth embodiment, in addition to setting each power storage device 50 as a power storage device for cycle use and a power storage device for backup use by a simple method, By predicting the load power of the device 100 and the power generated by the solar power generation device 80, the power storage device 50 having a higher priority can be selected and charged. Furthermore, the storage battery control device 75 can preferentially select and charge the power storage device 50 located near the load device 100 where demand is expected to increase.

[Seventh Embodiment]
Next, as a seventh embodiment, an example in which the storage battery control device of the present invention is applied to an AC power supply system including a photovoltaic power generation device (PV) will be described.
FIG. 14: is a block diagram which shows schematic structure of the alternating current power feeding system which concerns on 7th Embodiment of this invention.
For example, in the first embodiment described above, an example of a storage battery control device used in a DC power supply system that supplies DC power to the load device 100 has been described. However, AC power supply that supplies alternating current (for example, AC 400 V) to the load device 100 is described. The storage battery control device of the present invention can also be applied to the system.

  Compared with the DC power supply system 1 shown in FIG. 1, the AC power supply system 1F shown in FIG. 14 omits the DC power supply device 20 shown in FIG. 1, and connects the DC voltage supply paths P11 and N11 shown in FIG. The difference is that the voltage supply path ACL11 is replaced. In FIG. 14, a load device 100 is a load device that receives a three-phase or single-phase AC voltage as an input.

  In the AC power feeding system 1F having the above-described configuration, the high-voltage AC voltage (for example, three-phase AC 6600V) supplied from the commercial power system 2 is stepped down to a predetermined low-voltage AC voltage (for example, three-phase AC 400V) by the transformer 12, and this low voltage The AC voltage is output to the power supply path ACL11 which is the main power supply line.

A plurality of power storage devices 53-1, 53-2,..., 53-m are connected to the power supply path ACL11. In the following description, when the power storage device 53-1 to the power storage device 53-m are collectively referred to as the “power storage device 53”.
The power storage device 53 includes a bidirectional DC / AC converter (inverter and converter) 513A and a transformer 513B.

The control operation of the storage battery control device 70 in the AC power supply system 1F shown in FIG. 14 differs only in that the DC power voltage in the DC power supply system 1 is replaced with an AC voltage, and the basic operation is the storage battery control device shown in FIG. This is the same as the operation at 70.
That is, the storage battery control device 70 uses each of the power storage devices 53-1, 53-2,..., 53 -m for cycle use or backup depending on the number of cycles of each of the plurality of power storage devices 53. Set to use. The detailed control operation is the same as that of the storage battery control device 70 shown in FIG.
Thereby, in AC power feeding system 1F, when there are a plurality of power storage devices 50, a plurality of power storage devices 53 can be efficiently operated by a simple method.

As mentioned above, although embodiment of this invention was described, in the said embodiment, each process of the storage battery control apparatus 70, the storage battery control apparatus 71, the storage battery control apparatus 72, the storage battery control apparatus 73, the storage battery control apparatus 74, and the storage battery control apparatus 75. The functions of the units may be realized by dedicated hardware, and a program for realizing the functions of each processing unit is recorded on a computer-readable recording medium and recorded on the recording medium. The program may be realized by reading the executed program into a computer system and executing it.
That is, the storage battery control device 71 to the storage battery control device 75 have a computer system inside. A series of processes related to the above-described process is stored in a computer-readable recording medium in the form of a program, and the above-described process is performed by the computer reading and executing this program. Here, the computer-readable recording medium refers to a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, and the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program. The “computer system” here includes an OS and hardware such as peripheral devices.

  Although the embodiments of the present invention have been described above, the correspondence between the present invention and the above-described embodiments will be supplementarily described. That is, the storage battery control device according to the present invention corresponds to the storage battery control device 70, the storage battery control device 71, the storage battery control device 72, the storage battery control device 73, the storage battery control device 74, or the storage battery control device 75. In addition, the power supply device according to the present invention corresponds to the DC power supply device 20 or the power receiving facility 10. The power storage device in the present invention corresponds to the power storage device 50, the power storage device 51, the power storage device 52, or the power storage device 53. Further, the storage battery characteristic determination unit in the present invention corresponds to the storage battery characteristic determination unit 702, and the control unit in the present invention corresponds to the control unit 703. Moreover, the power storage device information 711 corresponds to the charge / discharge history information in the present invention, and corresponds to, for example, information on the number of cycles 713 and the usage period 714.

  (1) In the above embodiment, for example, in the DC power supply system 1 shown in FIG. 1, the storage battery control device 70 has a plurality of power supply paths for supplying power from the DC power supply device 20 (power supply device) to the load device 100. When the power storage device 50 is connected as an auxiliary power supply device, the storage battery control device 70 controls the charging / discharging operation of each of the plurality of power storage devices 50, and charges the storage batteries 511 included in each of the plurality of power storage devices 50. Based on charge / discharge history information (for example, the number of cycles and usage period) of the storage battery, a storage battery characteristic determination unit 702 that determines characteristics during discharge, and a determination result of characteristics of the storage battery 511 during charge / discharge , And a control unit 703 that controls each usage mode of the plurality of power storage devices 50.

In the storage battery control device 70 having such a configuration, the power storage device is determined based on past charge / discharge history information (for example, the number of cycles 713 and the use period 714) for each of the plurality of power storage devices 50 connected to the power feeding paths P11 and N11. The characteristic at the time of charging / discharging of the storage battery 511 in 50 is determined. Then, control unit 703 sets the usage mode of each power storage device 50 based on the determination result of the characteristics at the time of charging / discharging of storage battery 511 included in each power storage device 50.
Thereby, the storage battery control device 70 (storage battery control device) can efficiently operate a plurality of power storage devices by a simple method.

(2) In the above embodiment, a plurality of types of power storage devices are mixed in the plurality of power storage devices 50, and the control unit 703 controls each of the plurality of power storage devices 50 according to the type of the power storage device 50. Control usage.
As described above, the power storage device 50 may be a power storage device including the same type of storage battery, or a different type of storage battery, for example, a power storage device including a lead battery, a nickel metal hydride battery, or a lithium ion battery. It's okay. Then, the storage battery control device 70 sets, for example, the power storage device 50 including a lead battery or a lithium ion battery having a long cycle life to a cycle application by the control unit 703, and sets the power storage device 50 including a nickel hydride battery having a short cycle life. Set for backup purposes.
Thereby, the storage battery control device 70 (storage battery control device) can set the usage mode of the power storage device 50 including the different types of storage batteries 511 based on the type of the storage battery 511.

(3) Moreover, in the said embodiment, in the charging method of the said some electrical storage apparatus 50, several types of charging methods are mixed, and the control part 703 respond | corresponded to each usage condition of the several electrical storage apparatus 50. Select the type of charging method.
As described above, in the storage battery control device 70, the control unit 703 selects the type of charging method according to each usage mode of the power storage device 50. For example, the storage battery 511 for cycle use is charged by rapid charging, and the storage battery 511 for backup use is charged by constant voltage float charging. Further, in the power storage device 50, charging is performed by selecting any one of a constant voltage charging method, a constant current charging method, or a combination method of constant voltage charging and constant current charging according to the type of the storage battery 511. .
Thereby, the storage battery control apparatus 70 (storage battery control apparatus) can select the kind of charging method according to each utilization mode of the some electrical storage apparatus 50. FIG.

  (4) Moreover, in the said embodiment, the storage battery characteristic determination part 702 determines the change of the characteristic at the time of charging / discharging of the storage battery 511 based on the cycle number which repeated charging / discharging exceeding predetermined | prescribed discharge depth, and is controlled. When the number of cycles of the storage battery 511 is equal to or less than a predetermined reference number, the unit 703 first uses the power storage device 50 including the storage battery 511 by repeatedly charging and discharging beyond a predetermined discharge depth (for example, When the number of cycles of the storage battery exceeds a predetermined reference number, the power storage apparatus including the storage battery is normally charged so as to ensure a predetermined charge amount. It is set as the power storage device 50 of the second application (for example, backup application) used so as to wait for the opportunity to discharge.

If it is the storage battery control apparatus 70 (storage battery control apparatus) of such a structure, the storage battery characteristic determination part 702 will determine the change of the charging / discharging characteristic of the storage battery 511 contained in the electrical storage apparatus 50 by the cycle number of charging / discharging. And the storage battery control apparatus 70 sets the electrical storage apparatus 50 containing the storage battery 511 below the reference | standard number of cycles as a power storage apparatus of a 1st application (for example, cycle use), and the cycle number was predetermined. The power storage device including the storage battery 511 exceeding the reference number is set as the power storage device for the second use (for example, backup use).
Thereby, the storage battery control device 70 (storage battery control device) determines the change in the charge / discharge characteristics of the power storage device 50 based on the number of charge / discharge cycles, and sets the power storage device 50 to the first use (for example, cycle use). Alternatively, it can be determined whether to set the second application (for example, backup application).

  (5) Moreover, in the said embodiment, as shown to the storage battery control apparatus 71 of FIG. 4, for example, the storage battery characteristic determination part 702 is based on the use period and lifetime of the storage battery 511 in the electrical storage apparatus 51. The remaining usable period of the storage battery 511 is determined, and the control unit 703 determines that the power storage device 51 including the storage battery 511 is a predetermined amount when the remaining usable period of the storage battery 511 is equal to or longer than a predetermined reference period. When it is set as the power storage device 51 of the first application (for example, cycle application) that repeatedly uses charging and discharging beyond the depth of discharge, and the remaining usable period of the storage battery 511 is less than a predetermined predetermined reference period In addition, the power storage device 51 including the storage battery 511 is normally charged so as to secure a predetermined charge amount and is used for waiting for discharge (for example, a battery). Set as a charge-up applications).

If it is the storage battery control apparatus 71 (storage battery control apparatus) of such a structure, the storage battery characteristic determination part 702 will change the remaining available period of the storage battery 511 contained in the electrical storage apparatus 50 by the available period determination part 704 to a storage battery. The determination is made based on the use period 714 and the life period 722 of 511. Then, when the remaining available period of the storage battery 511 is equal to or longer than a reference period (for example, 5 years), the storage battery control device 71 uses the power storage device 51 including the storage battery 511 for the first application (for example, cycle application). When set as the power storage device 51 and the remaining available period of the storage battery 511 is less than the reference period, the power storage device 51 including the storage battery 511 is set as the power storage device 51 for the second application (for example, backup use). .
Thereby, the storage battery control device 71 (storage battery control device) determines the remaining usable period of the power storage device 50, and uses the power storage device 50 for the first application (for example, cycle application) based on the remaining usable period. ) Or a second application (for example, backup application) can be selected.

  (6) Moreover, in the said embodiment, in the storage battery control apparatus 72 (storage battery control apparatus) shown in FIG. 6, for example, the storage battery characteristic determination part 702 is the position where each of the some electrical storage apparatus 50 is connected to an electric power feeding path. Based on the position at which the load device 100 is connected to the power supply path, the power loss amount when power is supplied from each of the plurality of power storage devices 50 to the load device 100 is determined, and the control unit 703 determines the storage battery characteristics. Based on the amount of power loss determined by unit 702, power storage device 50 that performs charging and discharging is selected.

With the storage battery control device 72 having such a configuration, for example, when discharging from the power storage device 50 for cycle use to the power supply paths P11 and N11, the storage battery characteristic determination unit 702 causes the power supply path loss calculation unit 705 to perform the cycle. Information on the amount of power loss on the power feeding path when power is supplied to the load device 100 from each of the power storage devices 50 for use is calculated.
In other words, the power supply path loss calculation unit 705 includes position information where each of the cycle-use power storage devices 50 is connected to the power supply path system, position information where the load device 100 is connected to the power supply path system, and the power storage apparatus 50. The amount of power loss that occurs on the power supply path when current flows from the power storage device 50 to the load apparatus 100 with reference to the length of the power distribution path in the power supply path from the power supply device to the load device 100 and the information on the conductor resistance of the power distribution line Is calculated.

Then, the control unit 703 selects the power storage device 50 that supplies power to the load device 100 based on the information on the amount of power loss that occurs on the power supply path calculated by the power supply path loss calculation unit 705.
Thereby, the storage battery control device 72 can select the power storage device 50 that performs charging and discharging so that the amount of power loss generated on the power supply path from the power storage device 50 to the load device 100 is reduced.

  (7) In the above embodiment, for example, in the DC power supply system 1 </ b> C illustrated in FIG. 8, each of the plurality of power storage devices 52 detects the ambient temperature around the storage battery 511 included in the power storage device 52. The detection unit 515 is provided, and the storage battery characteristic determination unit 702 is based on the detection result of the ambient temperature around the storage battery 511 detected by the temperature detection unit 515, and the storage battery 511 included in each of the plurality of power storage devices 52. The control unit 703 selects the power storage device 52 that performs charging / discharging based on the determination result of the storage battery characteristic determination unit 702.

If it is the storage battery control apparatus 73 (storage battery control apparatus) of such a structure, the temperature detection part 515 will be provided in the electrical storage apparatus 52, and the ambient temperature around the storage battery 511 will be detected by this temperature detection part 515. The power storage device 52 notifies the storage battery control device 73 of information on the detected value of the ambient temperature around the storage battery 511. The temperature characteristic determination unit 706 in the storage battery characteristic determination unit 702 refers to the temperature characteristic data 723 stored in the power storage device DB 710 based on the ambient temperature around the storage battery 511, and determines whether or not the power storage device 52 is operable. Determine.
Thereby, the storage battery control device 73 can select the power storage device 52 to be operated by excluding the power storage device 52 outside the operating temperature range.

  As mentioned above, although embodiment of this invention was described, the storage battery control apparatus of this invention, DC power supply system, and AC power supply system are not limited only to the above-mentioned example of illustration, and deviate from the summary of this invention. Of course, various modifications can be made within the range not to be performed.

1, 1A, 1B, 1C, 1D, 1E ... DC power supply system (power supply system),
1F ... AC power feeding system (power feeding system),
2 ... Commercial power system, 10 ... Power receiving equipment, 20 ... DC power supply (power supply),
50, 51, 52, 53 ... power storage device, 60 ... energy management device,
70, 71, 72, 73, 74, 75 ... storage battery control device,
80 ... Solar power generation device, 90 ... Power conditioner (PCS),
100 ... load device, 511 ... storage battery, 512 ... cycle number detection unit,
512A ... use period detector, 513 ... DC / DC converter,
514 ... mode control unit, 515 ... temperature detection unit,
701: Storage battery information collection unit, 702: Storage battery characteristic determination unit,
703 ... Control unit, 704 ... Available period determination unit,
705 ... Power supply path loss calculation unit, 706 ... Temperature characteristic determination unit,
707 ... surplus power calculation unit, 707A ... surplus power prediction unit,
708 ... PV power generation amount prediction unit, 709 ... Load power prediction unit,
711 ... Power storage device information

Claims (11)

When a plurality of power storage devices are connected as auxiliary power supply devices to a power supply path for supplying power from a power supply device to a load device, the storage battery control device controls each charge / discharge operation of the plurality of power storage devices,
A storage battery characteristic determination unit that determines characteristics at the time of charging / discharging of the storage battery included in each of the plurality of power storage devices based on history information of charging / discharging of the storage battery;
Based on the determination result of the characteristics at the time of charging / discharging of the storage battery, a control unit that controls each usage mode of the plurality of power storage devices;
A storage battery control device comprising: In the plurality of power storage devices, a plurality of types of power storage devices are mixed,
The controller is
The storage battery control device according to claim 1, wherein a usage mode of each of the plurality of power storage devices is controlled according to a type of the power storage device. A plurality of types of charging methods are mixed in the plurality of power storage device charging methods,
The controller is
The storage battery control device according to claim 1 or 2, wherein a type of the charging method is selected according to a usage mode of each of the plurality of power storage devices. The storage battery characteristic determination unit
A change in characteristics during charging and discharging of the storage battery is determined based on the number of cycles in which charging and discharging are repeated beyond a predetermined depth of discharge,
The controller is
When the number of cycles of the storage battery is equal to or less than a predetermined reference number, the power storage device including the storage battery is set as a power storage device for a first application that is used by repeatedly charging and discharging beyond a predetermined depth of discharge,
When the number of cycles of the storage battery exceeds a predetermined reference number, the power storage device including the storage battery is normally used to wait for an opportunity to be charged and discharged so as to ensure a predetermined charge amount. The storage battery control device according to any one of claims 1 to 3, wherein the storage battery control device is set as a power storage device for a specific use. The storage battery characteristic determination unit
Based on the usage period and lifetime of the storage battery in the power storage device, determine the remaining available period of the storage battery,
The controller is
When the remaining usable period of the storage battery is equal to or longer than a predetermined reference period, the power storage apparatus for the first application that uses the power storage apparatus including the storage battery by repeatedly charging and discharging beyond a predetermined depth of discharge. Set as
When the remaining usable period of the storage battery is less than a predetermined reference period, the power storage device including the storage battery is normally charged to ensure a predetermined charge amount and waits for discharge. The storage battery control device according to any one of claims 1 to 3, wherein the storage battery control device is set as a power storage device for a second application to be used as described above. The storage battery characteristic determination unit
Power is supplied from each of the plurality of power storage devices to the load device based on a position where each of the plurality of power storage devices is connected to the power supply path and a position where the load device is connected to the power supply path. To determine the amount of power loss when
The controller is
The storage battery control device according to any one of claims 1 to 5, wherein a power storage device that charges and discharges is selected based on the power loss amount determined by the storage battery characteristic determination unit. Each of the plurality of power storage devices is provided with a temperature detection unit that detects an ambient temperature around a storage battery included in the power storage device,
The storage battery characteristic determination unit
Based on the detection result of the ambient temperature around the storage battery detected by the temperature detection unit, determine whether or not the storage battery included in each of the plurality of power storage devices can be operated,
The controller is
The storage battery control device according to any one of claims 1 to 6, wherein a storage device that performs charging and discharging is selected based on a determination result of the storage battery characteristic determination unit. The controller is
By setting each output voltage of the plurality of power storage devices to different values,
The storage battery control device according to any one of claims 1 to 7, wherein, in the plurality of power storage devices, a priority order of power storage devices that start discharging is set in the power feeding path. Power is supplied from the power supply device to the load device connected to the power supply path of the power supply device via the power supply path, and a plurality of power storage devices are connected to the power supply path as auxiliary power supply devices. Is a power supply system that is connected to the power supply path and supplies power from the photovoltaic power generation apparatus to the power supply path,
A storage battery characteristic determination unit that determines characteristics at the time of charging / discharging of the storage battery included in each of the plurality of power storage devices based on history information of charging / discharging of the storage battery;
Based on the determination result of the characteristics at the time of charging / discharging of the storage battery, a control unit that controls each usage mode of the plurality of power storage devices;
A power supply system comprising: A storage battery control method in a storage battery control device that controls charging / discharging operations of each of the plurality of power storage devices when a plurality of power storage devices are connected as auxiliary power supply devices to a power supply path that supplies power from the power supply device to the load device. There,
A storage battery characteristic determination procedure for determining characteristics at the time of charge / discharge of a storage battery included in each of the plurality of power storage devices based on charge / discharge history information of the storage battery,
Based on the determination result of the characteristics at the time of charge and discharge of the storage battery, a control procedure for controlling each usage mode of the plurality of power storage devices;
The storage battery control method characterized by including. When a plurality of power storage devices are connected as auxiliary power supply devices to a power supply path that supplies power from the power supply device to the load device, the computer of the storage battery control device that controls the charge / discharge operation of each of the plurality of power storage devices,
A storage battery characteristic determination procedure for determining characteristics at the time of charge / discharge of a storage battery included in each of the plurality of power storage devices based on charge / discharge history information of the storage battery,
Based on the determination result of the characteristics at the time of charge and discharge of the storage battery, a control procedure for controlling each usage mode of the plurality of power storage devices;
A program for running

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