JP7021456B2 - Storage control system, storage control method and storage control program - Google Patents

Description

The present invention relates to a power storage control system, a power storage control method, and a power storage control program.

In recent years, a power storage system for storing the power generated by a photovoltaic power generation device to expand the use of green power, and for using the power stored at night to perform a peak shift during the daytime when power demand is tight. Is coming to be used. At this time, if the power capacity to be stored cannot be secured by one storage battery, a power storage system configured by connecting a plurality of storage batteries is used.

Further, in a power storage system provided with a plurality of storage areas, a table in which the order of charging or discharging is preset according to at least two parameters defining the life and output of the storage battery is provided, and the table is referred to. A device for determining a storage battery to be charged or discharged among a plurality of storage batteries has been proposed (Patent Document 1).

Japanese Unexamined Patent Publication No. 2013-179729

In a storage battery system equipped with multiple storage areas, if each storage battery is used randomly, the frequency of use of each storage battery, that is, the number of times of charging and discharging may be biased, and some storage batteries may reach the end of their life at an early stage. .. When some of the storage batteries reach the end of their life, the entire storage battery system does not meet the specified performance, so the life of the system is shortened, or the storage batteries that have reached the end of their life need to be replaced, resulting in extra maintenance costs. There was a problem that it took.

The present invention has been made in view of such a situation, and suppresses the bias of deterioration in a plurality of storage batteries provided in a storage battery system.

In order to solve the above problems, the electricity storage control system of the present invention is used.
With multiple storage batteries that store power,
A plurality of output control devices that are connected to each of the storage batteries, and based on the power consumption of the load connected to the storage battery, start discharging by the storage battery and output to the load.
The number of times of charging / discharging from the start of discharging of the storage battery to the completion of discharging and charging of a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is acquired for the plurality of storage batteries, and the discharging is performed. When the difference in the number of times of charging and discharging of each storage battery spreads to a predetermined value or more by starting the above, the output control device is notified of a stop command for stopping the discharge of the storage battery to stop the discharge. ..

As a result, the number of times of charging and discharging of a plurality of storage batteries can be averaged, variation in deterioration can be suppressed, and maintenance work can be reduced.

In the storage control system, when the power consumption of the load exceeds the discharge power of the storage battery being discharged, the stop control device of the storage battery stopped by the stop command is among the stopped storage batteries. Discharging of the storage battery may be started by notifying the output control device connected to the storage battery of a release command for releasing the stop.

As a result, even when the number of storage batteries to be discharged is increased according to the power consumption, the storage battery to be discharged is determined based on the number of charge / discharge times, and the power can be supplied according to the power consumption, and the deterioration of each storage battery is achieved. It is possible to suppress the variation of.

In the storage control system, when the N storage batteries are being discharged and the power consumption of the load is equal to or less than the discharge power of the N-1 storage batteries, the stop control device is discharging the storage battery. Among the storage batteries, the output control device connected to the storage battery having the highest number of charge / discharge cycles may be notified of the stop command to stop the discharge of the storage battery.

As a result, even when the number of storage batteries to be discharged is reduced according to the power consumption, the storage battery to stop the discharge is determined based on the number of charge / discharge times, and each storage battery can be supplied with the power corresponding to the power consumption. It is possible to suppress the variation in deterioration of.

The storage control system stops discharging the storage battery when the storage battery is being discharged and there is another storage battery that can be discharged, and the discharge amount of the storage battery being discharged exceeds a threshold value. The discharge may be stopped by notifying the output control device of the stop command to be stopped.

As a result, it is possible to prevent only a specific storage battery from being continuously discharged and deteriorating, and it is possible to suppress variations in deterioration of each storage battery.

In order to solve the above problems, the electricity storage control method of the present invention is used.
A step in which a plurality of output control devices connected to each of the plurality of storage batteries start discharging by the storage battery and output to the load based on the power consumption of the load connected to the storage battery.
The number of times the stop control device performs charging / discharging from the start of discharging the storage battery to the completion of discharging and charging a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is defined for the plurality of storage batteries. A step of notifying the output control device of a stop command for stopping the discharge of the storage battery and stopping the discharge when the difference in the number of charge / discharge times of each storage battery becomes wider than a predetermined value due to the acquisition and the start of the discharge. And include.

In order to solve the above problems, the electricity storage control system of the present invention is used.
A plurality of storage battery systems including a storage battery for storing electric power, a plurality of power conditioners for controlling charging / discharging of the storage battery, and a plurality of storage battery systems.
Each power conditioner of the plurality of storage battery systems is equipped with a control device that issues a command regarding charging / discharging of the storage battery.
The control device is
An output control unit that determines at least one storage battery that is permitted to be discharged based on the power consumption of the load connected to the storage battery, and issues a discharge permission command that permits discharge to the power conditioner that controls the storage battery.
The number of times of charging / discharging from the start of discharging of the storage battery to the completion of discharging and charging of a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is acquired for the plurality of storage batteries, and the discharging is performed. A stop control unit that issues a discharge stop command to the power conditioner that controls the storage battery to stop the discharge of the storage battery when the difference in the number of times of charging and discharging of each storage battery widens by starting
A storage control system equipped with.

As a result, the number of times of charging and discharging of a plurality of storage batteries can be averaged, variation in deterioration can be suppressed, and maintenance work can be reduced.

In the storage control system, when the power consumption of the load exceeds the discharge power of the storage battery being discharged, the output control unit is the stop control unit based on the number of times of charging / discharging of the stopped storage batteries. The output control unit may issue a discharge permission command to the power conditioner that controls the storage battery by releasing the stop of the storage battery stopped by.

As a result, even when the number of storage batteries to be discharged is increased according to the power consumption, the storage battery to be discharged is determined based on the number of charge / discharge times, and the power can be supplied according to the power consumption, and the deterioration of each storage battery is achieved. It is possible to suppress the variation of.

In the storage control system, when the N storage batteries are being discharged and the power consumption of the load is equal to or less than the discharge power of the N-1 storage batteries, the stop control unit is discharging the storage battery. Among the storage batteries, a discharge stop command may be issued to the power conditioner that controls the storage battery having the largest number of charge / discharge cycles.

As a result, even when the number of storage batteries to be discharged is reduced according to the power consumption, the storage battery to stop the discharge is determined based on the number of charge / discharge times, and each storage battery can be supplied with the power corresponding to the power consumption. It is possible to suppress the variation in deterioration of.

In order to solve the above problems, the electricity storage control method of the present invention is used.
A control device that issues a command regarding charging / discharging of the storage battery to each power conditioner of the storage battery system consisting of a storage battery that stores electric power, a plurality of power conditioners that control the charging / discharging of the storage battery, and a plurality of power conditioners.
A step of determining at least one storage battery to be discharged based on the power consumption of the load connected to the storage battery, and issuing a discharge permission command to the power conditioner controlling the storage battery to allow the storage battery to be discharged.
The step of outputting the discharge power from the storage battery to the load,
The number of times of charging / discharging from the start of discharging of the storage battery to the completion of discharging and charging of a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is acquired for the plurality of storage batteries, and the discharging is performed. A storage control method that executes a step of issuing a discharge stop command to the power conditioner that controls the storage battery when the difference in the number of times of charging and discharging of each storage battery spreads to a predetermined value or more by starting.

In the storage control method, when the power consumption of the load exceeds the discharge power of the storage battery being discharged, the storage battery stopped by the control device based on the number of times of charging / discharging among the stopped storage batteries. The stop may be released and a discharge permission command may be issued to the power conditioner that controls the storage battery.

In the storage control method, when the N storage batteries are being discharged and the power consumption of the load is equal to or less than the discharge power of the N-1 storage batteries, the storage batteries being discharged are charged. A discharge stop command may be issued to the power conditioner that controls the storage battery having the largest number of discharges.

The present invention for solving the above problems may be a power storage control program for causing a computer to execute each step of the power storage control method.

The means for solving the above-mentioned problems can be used in combination as much as possible.

According to the present invention, it is possible to suppress the bias of deterioration in a plurality of storage batteries provided in the power storage control system.

It is a block diagram which shows the structural example of one Embodiment of a power control system. It is a figure which shows the functional block of a control device and a power conditioner. It is a figure which shows the hardware configuration of a control device. It is a figure which shows the hardware configuration of a power conditioner. It is explanatory drawing of the electricity storage control method executed by a control device. It is explanatory drawing of the electricity storage control method executed by a power conditioner. It is explanatory drawing of the electricity storage control method executed by the control apparatus which concerns on Embodiment 2. FIG.

Hereinafter, specific embodiments to which the present technology is applied will be described in detail with reference to the drawings.
<Embodiment 1>
"System configuration"
FIG. 1 is a block diagram showing a configuration example of an embodiment of a power control system to which the present technology is applied. The power control system shown in FIG. 1 is a hybrid system including a power storage control system 10 and a photovoltaic power generation system 50. The power storage control system 10 and the photovoltaic power generation system 50 are connected to the power system 71 and the load 73 via the breaker (MB) 72.

The photovoltaic power generation system 50 includes a photovoltaic power generation module 5 and a power conditioner (PCS) 6, and converts the electric power generated by the photovoltaic power generation module 5 into AC power by the power conditioner 6. The AC power from the photovoltaic power generation system 50 is used for consumption by the load 73, reverse power flow to the power system 71, and storage by the storage control system 10. The power control system may include, or is not limited to, a power generation system using natural energy such as wind power or hydraulic power, a private power generation system using fuel, or the like, in place of the photovoltaic power generation system 50. Further, the photovoltaic power generation system 50 may be omitted.

The storage control system 10 includes a plurality of storage battery systems and a control device 1, one storage battery system includes a storage battery 2A and a DC / DC converter 3A, and the other storage battery system has a storage battery 2B and DC / DC /. It is equipped with a DC converter 3B.

The storage batteries 2A and 2B are charged by storing the electric power supplied from the electric power system 71 or the photovoltaic power generation system 50. Further, the storage batteries 2A and 2B supply electric power to the load 73 by discharging the stored electric power. The storage batteries 2A and 2B are configured in the same manner, respectively, and are hereinafter referred to as storage batteries 2 when it is not necessary to distinguish between the storage batteries 2A and 2B. Similarly, the DC / DC converters 3A and 3B, the power conditioners 4A and 4B, and the power meters 74A and 74B are also referred to as the DC / DC converter 3, the power conditioner 4, and the power meter 74 when no distinction is necessary. ..

The storage battery 2 can store a predetermined amount of electric power, and can maintain a specified charging capacity until it is charged and discharged a specified number of times. Here, the ratio of the remaining charge of the electric power stored in the storage battery 2 to the rated capacity in which the storage battery 2 can store electric power is referred to as the charged state of the storage battery 2, and the discharge of the storage battery 2 is started. The number of times of charging / discharging from the above to the completion of discharging and the charging of a predetermined amount again is referred to as the number of times of charging / discharging. In other words, the storage battery 2 is charged, the charged state with the highest remaining charge is fully charged, the storage battery 2 is discharged, and the charged state with the remaining charge dropped to the specified value is the discharged completed state (discharge completed state). ), The number of times of charge / discharge is satisfied when the charge / discharge is performed once from the start of discharging the fully charged storage battery 2 to the time when the fully charged state is charged again after the discharge is completed. It is called the number of discharges.

The DC / DC converter 3 bidirectionally converts the voltage of the electric power supplied from the power conditioner 4 to the storage battery 2 and the voltage of the electric power discharged from the storage battery 2 to the power conditioner 4.

When the power conditioner 4 determines that the battery is discharged based on the charge / discharge mode, the load condition, etc., the power conditioner 4 converts the electric power discharged from the storage battery 2 into DC-AC and supplies it to the load 73, and stops the discharge. If it is determined, the discharge from the storage battery 2 is stopped, and the supply to the load 73 is stopped. Further, when the power conditioner 4 determines to perform charging based on the mode, the load condition, the charging state of the storage battery 2, etc., the power conditioner 4 uses the power supplied from the power system 71 or the photovoltaic power generation system 50 as AC-DC. It is converted and charged to the storage battery 2. This power conditioner 4 corresponds to an output control device in this embodiment.

The control device 1 issues a command regarding charging / discharging of the storage battery to each power conditioner of the plurality of storage battery systems. For example, a mode is instructed to the power conditioner 4, and the storage battery 2 is charged and discharged according to the mode. The timing at which the storage battery 2 is started to be discharged and the timing at which the storage battery 2 is charged can be appropriately selected depending on the purpose and the like. For example, if the purpose is to improve economic efficiency, charging is performed during a time when the electricity charge is low, and discharging is performed during a time when the electricity charge is high. Further, if the purpose is to prepare for a disaster, the surplus amount is provided for consumption by the load while always securing a predetermined remaining charge. Therefore, values such as the reference time for charging / discharging, the charging state, and the threshold value of power consumption can be selected as the mode for each purpose, and the mode set by the operator is notified to each power conditioner 4. Then, the storage battery 2 is charged and discharged at the timing corresponding to this mode. That is, in the present embodiment, the mode is a set value for each purpose indicating a reference for charging / discharging the storage battery 2. Further, when the power conditioner 4 starts the discharge of the storage battery 2, the control device 1 powers a stop command for stopping the discharge of the storage battery when the difference in the number of charge / discharge times of each storage battery widens to a predetermined value or more. Notify the conditioner 4 to stop the discharge. The control device 1 corresponds to a stop control device in this embodiment.

FIG. 2 is a diagram showing functional blocks of the control device 1 and the power conditioner 4. As shown in FIG. 2, the control device 1 has a data acquisition unit 11, a stop determination unit 12, and an instruction unit 13. From the power conditioner 4, the data acquisition unit 11 indicates information indicating the start or stop of charging, information indicating the start or stop of discharging, information indicating the measured value of the power meter 74, information indicating the charging state of the storage battery 2, and the like. Is acquired as status information.

The stop determination unit 12 recognizes that the discharge of the storage battery 2 has started based on the state information acquired by the data acquisition unit 11, and charges the storage batteries 2A and 2B whether or not to stop the discharge of the storage battery 2. Judgment is made according to the number of discharges. For example, when the difference in the number of charge / discharge times of the storage batteries 2A and 2B widens to a predetermined value or more due to the discharge of the storage battery 2, it is determined that the discharge of the storage battery 2 is stopped, and the determination result is notified to the instruction unit 13. Further, the stop determination unit 12 determines the storage battery 2 to release the stop based on the power consumption of the load, that is, the storage battery 2 to be discharged, and notifies the instruction unit 13 of the determination result. For example, when the power consumption of the load exceeds the discharge power of the storage battery being discharged, the storage battery 2 having the least number of charge / discharge cycles among the stopped storage batteries 2 is released from the stop. Further, the stop determination unit 12 counts and stores the number of times of charging / discharging of each storage battery 2 based on the information indicating the start / stop of charging and the information indicating the start / stop of discharging. When each power conditioner 4 counts the number of charge / discharge times of each storage battery 2, the number of charge / discharge times is acquired from each power conditioner 4 via the data acquisition unit 11, and the stop determination unit 12 stores the memory. It may be configured to be stored in a storage device such as.

The instruction unit 13 transmits a discharge permission command, a discharge stop command, and a stop release command to the power conditioner 4 based on the power consumption of the load and the determination result notified from the stop determination unit 12. For example, by transmitting a discharge permission command to the power conditioner 4, it is possible to control the discharge by the power conditioner 4. Further, the discharge stop command is transmitted to the power conditioner 4 to stop the discharge of the storage battery 2, and the stop release command is transmitted to the power conditioner 4 to release the stop of the storage battery 2. Further, the instruction unit 13 instructs the power conditioner 4 of the charge / discharge mode by transmitting information indicating the mode to the power conditioner 4.

As shown in FIG. 2, the power conditioner 4 includes a charge control unit 41, a discharge control unit 42, a power measurement unit 43, and an inverter 44.

The charge control unit 41 controls the inverter 44 and the DC / DC converter 3, supplies the power AC-DC converted by the inverter 44 to the storage battery 2 via the DC / DC converter 3, and charges the storage battery 2.

The discharge control unit 42 controls the DC / DC converter 3 and the inverter 44, boosts the electric power discharged from the storage battery 2 by the DC / DC converter 3, performs DC-AC conversion by the inverter 44, and supplies the power to the load 73.

The power measuring unit 43 measures the power supplied from the power system 71 to the load 73 by the power meter 74, and notifies the data acquisition unit 11 and the discharge control unit 42.

The inverter 44 AC / DC converts the electric power supplied from the electric power system 71 or the photovoltaic power generation system 50. Further, the inverter 44 converts the electric power supplied from the DC / DC converter 3 into DC / AC.

The charge control unit 41 and the discharge control unit 42 charge the storage battery 2 and discharge from the storage battery 2 according to a plurality of modes such as an ecology mode, an economy mode, and a disaster mode instructed by the control device 1. Control the timing to make it.

FIG. 3 is a diagram showing the hardware configuration of the control device 1, and FIG. 4 is a diagram showing the hardware configuration of the power conditioner 4.

As shown in FIG. 3, the control device 1 includes, for example, a memory 16 connected to the CPU 15 via a bus, an input device 17, an output device 18, and a communication interface (communication IF) 19.

The memory 16 includes a main storage device and an auxiliary storage device. The main storage device is used as a work area of the CPU 15, a storage area for programs and data, and a buffer area for communication data. The main storage device is formed, for example, by Random Access Memory (RAM) or a combination of RAM and Read Only Memory (ROM).

The auxiliary storage device stores the program executed by the CPU 15 and the data used when executing the program. The auxiliary storage device is, for example, a hard disk drive (HDD), a solid state drive (SSD), a flash memory, or an electrically Erasable.
Programmable Read-Only Memory (EEPROM), etc. Further, the auxiliary storage device includes a portable storage medium that can be attached to and detached from the control device 1.

The input device 17 is used to input information and data to the control device 1. The input device 17 includes, for example, buttons, keys, a touch panel, and the like.

The output device 18 outputs information and data. The output device is, for example, a display device, a printer, a writing device for a storage medium, or the like. The output device 18 may include an audio output device such as a speaker. The communication IF 19 is an interface for communicating with another device, for example, the power conditioner 4.

The CPU 15 corresponds to a processing device in this embodiment. The CPU 15 is also called an MPU (Micro Processor Unit), a microprocessor, or a processor. The CPU 15 is not limited to a single processor, and may have a multiprocessor configuration. Further, a single CPU connected by a single socket may have a multi-core configuration. Even if at least a part of the above processing is performed by a processor other than the CPU, for example, a dedicated processor such as a Digital Signal Processor (DSP), Graphics Processing Unit (GPU), numerical arithmetic processor, vector processor, image processing processor, etc. good. Further, at least a part of the processing of each of the above parts may be an integrated circuit (IC) or another digital circuit. Further, an analog circuit may be included in at least a part of each of the above parts. Integrated circuits include LSI, Application Specific Integrated Circuit (ASIC), and programmable logic device (PL).
D) is included. The PLD includes, for example, a Field-Programmable Gate Array (FPGA). Each of the above parts may be a combination of a processor and an integrated circuit. The combination is called, for example, an MCU (Micro Controller Unit), a SoC (System-on-a-chip), a system LSI, a chipset, or the like.

The CPU 15 loads the program stored in the memory 16 into the main storage device and executes it. Programs such as an operating system and firmware are installed in the memory 16.

By executing the program, the CPU 15 functions as the data acquisition unit 11, the stop determination unit 12, and the instruction unit 13. The state information acquired by the data acquisition unit 11 and the number of charge / discharge counts counted by the stop determination unit 12 are stored in the memory 16.

Further, as shown in FIG. 4, the power conditioner 4 includes, for example, a memory 46, an input device 47, an output device 48, a communication interface (communication IF) 49, and an inverter 44 connected to the CPU 45 via a bus. .. As for the CPU 45, the memory 46, the input device 47, the output device 48, and the communication IF 49, the same ones as the CPU 15, the memory 16, the input device 17, the output device 18, and the communication IF 19 can be applied. do.

By executing the program, the CPU 45 functions as the charge control unit 41, the discharge control unit 42, and the power measurement unit 43. The input device 47 includes a power meter 74 and detects the power supplied from the power system 71 to the load 73. The output device 48 includes an output interface that outputs a control signal to the inverter 44 and the DC / DC converter 3, and sends the control signal to the inverter 44 and the DC / DC converter 3 to send the control signal to the inverter 44 and the DC / DC converter 3. Controls the operation of. The communication IF 49 communicates with another device, for example, another power conditioner 4, the control device 1, and the power conditioner 6 of the photovoltaic power generation system 50.

<< Storage control method >>
Next, the storage control method executed by the control device 1 and the power conditioner 4 will be described with reference to FIGS. 5 and 6.

The power conditioner 4 executes the process shown in FIG. 5 when the power is turned on or when the power conditioner 4 is instructed to start.

First, the CPU 45 of the power conditioner 4 refers to the mode and the command instructed by the control device 1 (step S10). The mode and command reference may be configured to store the mode and command received from the control device 1 in the memory 46 and read them from the memory 46, or may be configured to directly acquire the mode and the command from the control device 1 via the communication IF 49. good.

Further, the CPU 45 measures the power supplied from the power system 71 to the load 73 based on the detection signal by the power meter 74, and obtains the power consumption by the load 73 (step S20). When power is supplied from the photovoltaic power generation system 50 or another power conditioner 4, the power consumption is obtained by adding these powers to the power detected by the power meter 74.

Then, the CPU 45 determines whether or not to discharge based on the command, mode, and power consumption obtained in steps S10 and S20 (step S30). The determination as to whether or not to discharge is determined, for example, to receive a discharge permission command and to discharge when the power consumption exceeds a predetermined threshold value. It should be noted that this threshold value may be different for each mode. That is, in the economy mode, it is determined to discharge when the power consumption exceeds the threshold value for the economy mode, and in the ecology mode, it is determined to discharge when the power consumption exceeds the threshold value for the economy mode. do. Further, it may be determined whether or not the current time, the charging state, and the like are discharged depending on whether or not the conditions determined for each mode are satisfied. For example, in the case of the mode in which the peak shift is performed, it is determined that the battery is discharged if the current time is in the peak time zone (time zone in which power consumption is tight) and that the battery is not discharged in other time zones. Further, in the disaster mode, it is determined that if the charging state of the other storage battery 2 is at least a predetermined value, the battery is discharged, and if it is less than the predetermined value, the battery 2 is not discharged. It should be noted that the configuration is not limited to the configuration in which control is performed according to a plurality of modes, and it may be determined whether or not to discharge based only on the power consumption. It is determined that the storage battery 2 is not discharged even when the charge state is less than the predetermined value and the discharge is completed (steps S30, No).

If it is determined in step S30 to discharge (steps S30, Yes), the CPU 45 proceeds to step S40. The determination in step S30 is not limited to the case where the discharge is started from the state where the discharge is stopped, and the CPU 45 determines that the discharge is performed even when the discharge is continued while the discharge is started. (Step S30, Yes), the process proceeds to step S40, and it is determined whether or not a stop instruction has been received from the control device 1 (step S).
40). When this stop instruction is not received (steps S40, No), the CPU 45 sends a control signal for discharging to the inverter 44 and the DC / DC converter 3, discharges the storage battery 2, and loads this discharge power 73. (Step S50), and the process of FIG. 5 is completed. In step S50, the CPU 45 is not limited to the case where the discharge is started from the state where the discharge is stopped, but also when the discharge is continued while the discharge is started, the CPU 45 is the inverter 44 and the DC / DC converter. A control signal for discharging is sent to 3, and the storage battery 2 is discharged.

On the other hand, when it is determined in step S30 that the battery is not discharged (step S30, No) or when it is determined that the stop instruction is received in step S40 (step S40, Yes), the CPU 45 does not discharge the inverter 44 and DC / DC. The converter 3 is controlled (step S60). For example, if the discharge has already started, the inverter 44 gives an instruction to stop the discharge.
And DC / DC converter 3, the supply of discharge power is stopped, and the discharge of the storage battery 2 is stopped. In step S60, not only when the discharge is stopped from the state where the discharge is being performed, but also when the discharge is not continuously performed while the discharge is stopped, the CPU 45 determines that the discharge is not performed ( Step S30, No), the process proceeds to step S60, and a control signal is sent to the inverter 44 and the DC / DC converter 3 so as not to discharge.

Next, the CPU 45 determines whether or not to perform charging (step S70), and when it is determined to perform charging (step S70, Yes), the CPU 45 instructs the inverter 44 and the DC / DC converter 3 to charge the battery. This is done (step S80), and the process of FIG. 5 is terminated. For example, when the state of charge of the storage battery 2 becomes less than a predetermined value and the discharge is completed, the CPU 45 determines that the battery is charged. Further, the CPU 45 may determine whether or not charging is performed depending on whether or not elements such as the current time and the power generation state by the photovoltaic power generation system satisfy the conditions determined for each mode. For example, in the mode of performing peak shift, it is determined that charging is not performed if the current time is in the peak time zone (time zone when power consumption is tight), and charging is performed in other time zones. Also, in the economy mode, it is determined that charging will be performed if the current time is in the midnight time zone (time zone in which a cheap midnight electricity charge is applied), and that charging will not be performed in other time zones. do. In the ecology mode, charging is performed if the power is supplied by the photovoltaic power generation system, and charging is not performed if the power is supplied by the photovoltaic power generation system.

The CPU 45 repeatedly executes the process of FIG. 5 after the process of FIG. 5 is started, until the power is turned off, or until a stop is instructed.

Further, the control device 1 executes the process of FIG. 6 when the power is turned on or when the start is instructed. First, the CPU 15 of the control device 1 determines whether or not the discharge of the storage battery 2 has started (step S100). If the storage battery 2 is not discharged (step S100, No), the process of FIG. 6 is completed, and if the storage battery 2 is discharged (step S100, Yes), data such as the number of charge / discharge cycles and power consumption is acquired. (Step S110). The number of times of charging / discharging is determined by receiving a notification from the power conditioner 4 of the start / completion of discharging and the start / completion of charging, counting the number of times of charging / discharging, and storing it in the memory 16. It may be configured to read from, or it may be configured to be directly acquired from the power conditioner 4 via the communication IF 19. Further, the power consumption by the load 73 is also acquired from the power conditioner 4.

Then, the CPU 15 determines whether or not to stop the storage battery 2 based on the number of charge / discharge cycles (step S120). For example, when the CPU 15 increments the number of times of charging / discharging of the storage battery 2 determined to have started discharging in step S100, the difference from the number of times of charging / discharging of the other storage battery 2 expands to a predetermined value or more (for example, 2 or more). , It is determined that the discharge of the storage battery 2 is stopped. Specifically, when the number of times of charging / discharging of the storage battery 2A is larger than the number of times of charging / discharging of the storage battery 2B, the discharge of the storage battery 2A is started and the number of times of charging / discharging of the storage battery 2A is incremented. Since the difference from the number of charge / discharge times of 2B becomes wide, the discharge of the storage battery 2A is stopped. Further, in this case, if the discharge of the storage battery 2B is started and the number of times of charge / discharge of the storage battery 2B is incremented, the difference between the number of times of charge / discharge of the storage battery 2A and the number of times of charge / discharge of the storage battery 2B is reduced, so that the discharge of the storage battery 2B is discharged. Determines not to stop. When the number of charge / discharge of the storage battery 2A and the number of charge / discharge of the storage battery 2B are the same, when the discharge of the storage battery 2A is started and the number of charge / discharge of the storage battery 2A is incremented, the number of charge / discharge of the storage battery 2A and the number of charge / discharge of the storage battery 2B are increased. Although the difference from the number of charge / discharge times is widened, the discharge of the storage battery 2A is not stopped because it is less than a predetermined value (for example, 2). The predetermined value is not limited to 2, and may be set to 3 or more within a range in which a bias in the number of charge / discharge cycles can be tolerated.

When it is determined to stop the discharge (step S120, Yes), the CPU 15 notifies the power conditioner 4 of the discharge stop command and stops the discharge (step S130). The CPU 15 notifies the power conditioner 4 that controls the storage battery 2 that permits discharge other than the storage battery to be stopped of the discharge permission command. As a result, the discharge by the power conditioner 4 that controls the storage battery 2 to be stopped is stopped, and the other power conditioner 4 starts the discharge as shown in FIG.

Further, the CPU 15 determines whether or not to increase the number of storage batteries 2 to be discharged based on the power consumption (step S140). For example, the power consumption is PA, the discharge power of the storage battery is PB, the number of storage batteries 2 currently being discharged is N, and when the equation 1 is satisfied, it is determined that the number of storage batteries to be discharged is increased (.
Step S140, Yes).

PA> (N + 1) ・ PB ... (Equation 1)
When it is determined to increase the number of storage batteries 2 to be discharged, the CPU 15 determines the storage battery 2 to be discharged based on the number of charge / discharge cycles, releases the stop to the power conditioner 4 that controls the storage battery 2, and permits discharge. Notify the permission command (step S150). For example, among the stopped storage batteries 2, the storage battery 2 having the smallest number of charge / discharge cycles is released.

Since the power consumption is high in the situation where the equation 1 is satisfied in this way, the power conditioner 4 determines in step S30 shown in FIG. 5 that the discharge is started, and the stop instruction is canceled, so that also in step S40. Since it is determined that the stop instruction has not been received, the storage battery 2 is started to be discharged (step S50). That is, the number of storage batteries 2 to be discharged can be increased.

Further, the CPU 15 determines whether or not to reduce the storage battery 2 to be discharged based on the power consumption (step S160). For example, when the equation 2 is satisfied, it is determined that the number of storage batteries to be discharged is reduced (step S160, Yes).

PA <(N-1) ・ PB ... (Equation 2)
When it is determined to reduce the number of storage batteries 2 to be discharged, the CPU 15 determines the storage battery 2 to stop discharging based on the number of times of charging and discharging, and notifies the power conditioner 4 that controls the storage battery 2 of the discharge stop command (step). S170). For example, among the storage batteries 2 that are being discharged, the storage battery 2 that has the highest number of charge / discharge cycles is stopped.

The CPU 15 repeatedly executes the process of FIG. 6 after the process of FIG. 6 is started, until the power is turned off, or until a stop is instructed.

"effect"
As described above, according to the present embodiment, when the power conditioner 4 starts discharging the storage battery 2, if the difference in the number of times of charging and discharging of each storage battery widens, the discharging of the storage battery 2 is stopped. As a result, the number of charge / discharge cycles of each storage battery can be averaged, variation in deterioration can be suppressed, and maintenance work can be reduced.

Further, even when the number of storage batteries to be discharged is increased according to the power consumption, by determining the storage battery to be discharged based on the number of charge / discharge times, it is possible to supply the power corresponding to the power consumption and the deterioration of each storage battery. It is possible to suppress the variation of.

Furthermore, even when the number of storage batteries to be discharged is reduced according to the power consumption, by determining the storage battery to stop the discharge based on the number of charge / discharge times, it is possible to supply the power corresponding to the power consumption, and each storage battery. It is possible to suppress the variation in deterioration of.

In the present embodiment, as shown in FIG. 1, an example in which the power storage control system 10 mainly includes two storage batteries 2 is shown, but the present invention is not limited to this, and three or more storage batteries 2 may be provided. Further, in FIG. 1, one DC / DC converter 3 and one power conditioner 4 are connected to one storage battery 2, but the present invention is not limited to this, and a plurality of storage batteries are connected to one power conditioner 4. May be good.

<Embodiment 2>
In the above-described first embodiment, based on the number of times of charging / discharging of the storage battery that has started discharging, the number of times of charging / discharging is made uniform and the degree of deterioration is controlled by controlling so as to stop the discharging when the deviation of the number of times of charging / discharging becomes large. Is made uniform. In this case, even if the number of charge / discharge times is the same, if there is a difference in the discharge state per charge, the degree of deterioration will differ even if the storage battery has the same number of charge / discharge times as the charge / discharge is repeated. There is. Therefore, in the present embodiment, when the amount of discharge unevenly discharged from a specific storage battery reaches a predetermined value, the battery is switched to another storage battery and discharged. Since the other configurations are the same as those of the above-described first embodiment, the configurations different from those of the first embodiment will be mainly described, and the description of the same elements will be omitted.

In the present embodiment, the data acquisition unit 11 of the control device 1 acquires the discharge amount of each storage battery 2 from each power conditioner 4 at predetermined time intervals, and together with this, the charge start time, the charge completion time, the discharge start time, and the like. The discharge stop time and the like are stored as history information for each storage battery 2. In addition to this, the data acquisition unit 11 may acquire the power consumption of the load 73 and store it for each time zone.

The stop determination unit 12 discharges the storage battery 2 when the storage battery 2 is being discharged and there is another dischargeable storage battery 2, and the discharge amount of the storage battery during discharge exceeds the threshold value. The power conditioner 4 is notified of a stop command to stop the discharge. At this time, if the other storage battery 2 is stopped by the stop command, the stop command is canceled.

FIG. 7 is a diagram showing a storage control method according to the second embodiment. Since steps S100 to S170 are the same as those in the first embodiment, the description thereof will be omitted. After steps S160 and S170, the control device 1 determines whether or not the storage battery 2 is being discharged and there is another dischargeable storage battery 2, that is, whether or not there is a storage battery 2 to be switched (). Step S180). Here, the other storage battery 2 that can be discharged is, for example, one in which the charge rate is equal to or higher than a predetermined value and the bias in the number of times of charging does not increase even when the storage battery 2 is switched to the storage battery 2 currently being discharged and discharged. For example, as in step S150, the storage battery 2 is selected based on the number of charge / discharge cycles, and the charge rate of the storage battery 2 is obtained based on the history data. In this example, the charge rate is the ratio of the remaining power amount to the power amount charged at the time of full charge. Not limited to this, other scales may be used as long as the degree of charge can be known.

When the stop determination unit 12 determines that the switchable storage battery 2 does not exist (step S180, No), the process of FIG. 6 is terminated, and when it is determined that the switchable storage battery 2 exists (step S180, No). S180, Yes), the process proceeds to step S190.

In step S190, the control device 1 determines whether or not the discharge amount of the storage battery 2 being discharged exceeds the threshold value. As described above, if the currently discharged storage battery 2 is discharged in a state where another stopped storage battery (switchable storage battery) 2 is present, the discharge state will be biased, so that the discharge amount is a predetermined value. When the (threshold value) is reached, the discharge is stopped. Therefore, the control device 1 calculates the amount of discharge discharged during the period when the switchable storage battery 2 is stopped (hereinafter, also referred to as the amount of discharge during partial drive) with reference to the history information of the storage battery 2 being discharged. , It is determined whether or not this partial drive discharge amount exceeds the threshold value. Here, the threshold value may be a fixed value, or may be dynamically determined based on a season, a time zone, a load state, past history information, and the like. For example, the past discharge power amount in the discharging time zone (current time) may be obtained from the history information and divided by the number N of the storage batteries 2 as a threshold value. That is, the threshold value = the past discharge power amount / N in the discharge time zone may be used.

When it is determined that the amount of discharge during partial drive exceeds the threshold value (step S190, Yes), the control device 1 releases the stop if the switchable storage battery 2 is stopped by the stop command, and the power conditioner 4 A discharge permission command is transmitted to (step S200). note that,
If the switchable storage battery 2 is not stopped by the stop command, step S200 may be skipped.

Further, the control device 1 transmits a stop command to the power conditioner 4 connected to the storage battery 2 being discharged, and stops the discharge of the storage battery 2 (step S210).

After step S210, when it is determined in step S180 that the switchable storage battery 2 does not exist (step S180, No), or when it is determined that the discharge amount during partial drive does not exceed the threshold value (step S190, No). , The control device 1 ends the process of FIG. 7.

As described above, according to the second embodiment, when a part of the storage batteries 2 out of the plurality of storage batteries 2 is being discharged and the discharge amount reaches a predetermined value, the discharge of the storage battery 2 is stopped. , Switch to another storage battery 2 to discharge. As a result, it is possible to prevent only the specific storage battery 2 from being continuously discharged and deteriorating, and it is possible to accurately suppress the variation in deterioration.

1 Control device 2 (2A, 2B) Storage battery 3 (3A, 3B) Converter 4 (4A, 4B) Power conditioner 5 Solar power generation module 6 Power conditioner 10 Storage control system 50 Solar power generation system 71 Power system 73 Load 74 (74A, 74B) Power meter

Claims (6)

With multiple storage batteries that store power,
A plurality of output control devices that are connected to each of the storage batteries, and based on the power consumption of the load connected to the storage battery, start discharging by the storage battery and output to the load.
The number of times of charging / discharging from the start of discharging of the storage battery to the completion of discharging and charging of a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is acquired for the plurality of storage batteries, and the discharging is performed. When the difference between the number of times of charging and discharging of the storage battery that started discharging and the number of times of charging and discharging of other storage batteries that have stopped discharging widens to a predetermined value or more, the discharging is started. A storage control system including a stop control device that notifies the output control device of a stop command for stopping the discharge of the storage battery and stops the discharge. When the power consumption of the load connected to the storage battery exceeds the discharge power that can be discharged by the storage battery being discharged, the stop control device is stopped by the stop command among the stopped storage batteries. The storage control system according to claim 1, wherein a release command for releasing the stop of the storage battery is notified to the output control device connected to the storage battery to start discharging the storage battery. When the number of the storage batteries being discharged is N and the power consumption of the load is equal to or less than the discharge power of the N-1 storage batteries, the stop control device is among the discharging batteries. The storage control system according to claim 1 or 2, wherein the output control device connected to the storage battery having the largest number of charge / discharge cycles is notified of the stop command to stop the discharge of the storage battery. When the storage battery is being discharged and there is another dischargeable storage battery, when the amount of discharge power of the storage battery being discharged exceeds the threshold value, the discharge of the storage battery is stopped. The storage control system according to any one of claims 1 to 3, wherein a command is notified to the output control device to stop the discharge. A step in which a plurality of output control devices connected to each of the plurality of storage batteries start discharging by the storage battery and output to the load based on the power consumption of the load connected to the storage battery.
The number of times the stop control device performs charging / discharging from the start of discharging the storage battery to the completion of discharging and charging a predetermined amount is defined as the number of times of charging / discharging, and the number of times of charging / discharging is defined for the plurality of storage batteries. When the difference between the number of times of charging / discharging of the storage battery that has started discharging and the number of times of charging / discharging of another storage battery that has stopped discharging becomes wider than a predetermined value by acquiring and starting the discharge, the said A storage control method including a step of notifying the output control device of a stop command for stopping the discharge of a storage battery that has started discharging and stopping the discharge. A storage control program executed by a stop control device for stopping the discharge of the storage battery via a plurality of output control devices connected to each of the plurality of storage batteries.
The number of times of charging / discharging from the start of discharging of the storage battery to the completion of discharging and charging of a predetermined amount is defined as the number of times of charging / discharging, and the step of acquiring the number of times of charging / discharging for the plurality of storage batteries.
When the difference between the number of times of charging and discharging of the storage battery that has started discharging and the number of times of charging and discharging of other storage batteries that have stopped discharging becomes wider than a predetermined value by starting the discharging, the discharging is started. The step of determining whether or not to stop the discharge of the stored battery,
A storage control program including a step of notifying the output control device connected to the storage battery of a stop command and stopping the discharge when it is determined to stop the discharge of the storage battery.

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