JP2019062619A - Power storage system and storage battery discharging control method - Google Patents

Abstract

To provide a power storage system and a storage battery discharging control method by which, when communication with a high-order management server is disconnected in accordance with a discharging command from the high-order management server during an operation of discharging from a storage battery, increase of a circuit voltage is suppressed such that circuit power can be stabilized and occurrence of power loss in a power generation device can be suppressed.SOLUTION: The power storage system includes a storage battery 50 for storing commercial power at least from a circuit, a power conditioner 100 that performs power conversion during discharging and charging of the storage battery 50, and a controller 200 that controls charging/discharging of the storage battery 50. When connection with a high-order management server 2 is disconnected during an operation of discharging to a circuit side in response to a remote discharging command from the management server 2 and a circuit voltage V during the operation of discharging becomes equal to or higher than a predetermined voltage V1, the controller 200 performs control to switch the operation to a predetermined operation after stopping the discharging operation based on the remote discharging command.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a storage system and a storage battery discharge control method.

  BACKGROUND ART In recent years, with the spread of solar power generation technology, even in ordinary homes, power storage systems such as solar panels and power generation facilities have been installed in houses to perform power generation and charging, and power storage systems that use electric power are increasing. The storage system executes control to supply the power stored in the storage battery to the load when the power supply from the commercial power supply stops.

  On the other hand, the storage system is connected to a network such as the Internet, and is also managed by an integrated energy management system that performs balanced management of energy supply and consumption with other storage systems, power generation resources, etc. in a well-balanced manner. The storage system has a function of supplying energy from the storage battery to the system power supply side when there is a discharge instruction from the storage battery to the system power supply side from the integrated energy management system.

  In Patent Document 1, AC power is generated using renewable energy, and generation means for supplying generated power by linking it to a system power supply, charging means for a storage battery, and abnormality of the system power supply are detected. The second switching means for disconnecting the in-home load from the power generation means while maintaining the state in which the power generation means and the charging means are connected. And a grid interconnection device capable of stably performing a storage battery of an electric vehicle even in a state where a power source that generates electric power using renewable energy is disconnected from a power system.

JP, 2014-27856, A

  As described above, when the upper management server such as the integrated energy management system instructs the storage system to discharge the storage battery, the storage system performs a discharge operation to supply power to the system power supply side. However, if the communication between the upper management server and the storage system is interrupted during the discharge operation, the storage system is out of control by the upper management server.

  When the discharging operation is performed while the upper management server is in the discharging operation and the communication with the upper management server is disconnected, the system voltage increases when the demand for the system power decreases. When the grid voltage rises, the control voltage reaches a suppression voltage that suppresses the operation of a power generation device such as a solar panel that supplies generated power to the grid. When the grid voltage becomes equal to or higher than the suppression voltage, the power generation device has to be forced to the suppression operation. In this case, the storage battery is discharged to the grid, the grid voltage rises, and the grid power becomes unstable, and furthermore, the power generation device generates a power loss due to the suppression operation.

  The problem to be solved by the present invention is that, when the communication with the upper management server is interrupted during the discharge operation from the storage battery due to the discharge instruction of the upper management server, the increase in the system voltage is suppressed to stabilize the system power. It is an object of the present invention to provide a storage system and a storage battery discharge control method capable of suppressing the occurrence of power loss of a power generation device while achieving

  A storage system according to an embodiment includes a storage battery storing at least commercial power from a system, a power conversion device performing power conversion when discharging and charging the storage battery, and a control device performing charge and discharge control of the storage battery. Prepare. The control device receives a remote discharge command from the upper management server, and the communication with the management server is interrupted during the discharge operation to the system side, and the system voltage during the discharge operation becomes equal to or higher than a predetermined voltage In this case, control is performed to stop the discharge operation by the remote discharge command and to switch to a predetermined operation.

FIG. 1 is a diagram illustrating an example of a configuration of a power storage system according to an embodiment. FIG. 2 is a diagram illustrating an example of a configuration of a controller included in the power storage system according to the embodiment. FIG. 3 is a flowchart illustrating an example of a discharge control processing procedure of the storage battery by the power storage system according to the embodiment.

  The storage system 1 according to the embodiment described below includes a storage battery 50 for storing commercial power from at least a system, a power conversion device (power conditioner 100) for performing power conversion at the time of discharge and storage of the storage battery 50, and storage battery And 50. A control device (controller 200) for performing charge and discharge control of 50. The control device received a remote discharge command from the upper management server 2 and cut off communication with the management server 2 during discharge operation to the grid side, and the system voltage V during discharge operation became equal to or higher than a predetermined voltage In this case, control is performed to stop the discharge operation by the remote discharge command and switch to a predetermined operation.

  Further, the predetermined voltage controlled by the control device (controller 200) of the power storage system 1 according to the embodiment described below is suppressed so that the suppression of the power generation operation of the power generation device (sunlight panel PN) connected to the system is started. It is a value less than the voltage.

  In addition, the control device (controller 200) included in the storage system 1 according to the embodiment described below stores an operation log during discharge operation according to the remote discharge command, and after communication with the management server 2 is recovered, the management server 2 Notify the operation log to

  Further, the control device (controller 200) included in the storage system 1 according to the embodiment described below receives the remote discharge command from the upper management server 2 and communicates with the management server 2 during the discharge operation to the system side. Control for stopping the discharge operation by the remote discharge command and switching to the predetermined operation when the system voltage V during the discharge operation becomes equal to or higher than the predetermined voltage. I do.

  The storage battery discharge control method according to the embodiment described below includes at least storage battery 50 for storing commercial power from a system, and a power conversion device for performing power conversion at the time of discharge and storage of storage battery 50 (power conditioner 100 And a controller (controller 200) for performing charge / discharge control of the storage battery 50. The control device received a remote discharge command from the upper management server 2 and cut off communication with the management server 2 during discharge operation to the grid side, and the system voltage V during discharge operation became equal to or higher than a predetermined voltage In this case, control is performed to stop the discharge operation by the remote discharge command and switch to a predetermined operation.

  Hereinafter, embodiments of a storage system and a storage battery discharge control method according to the present invention will be described in detail with reference to the drawings. The components having the same functions in the embodiments are denoted by the same reference numerals and redundant description will be omitted.

(Embodiment)
The storage system according to the embodiment receives supply of a predetermined power system, for example, a commercial power supply (CP), and supplies power to a load (LD) such as a home appliance. In addition, the storage system supplies power generated by a power generation device using natural energy such as a solar panel to a load such as a home appliance through a power conversion device. Further, the storage system stores power supplied from a commercial power source and power generated by the power generation device in a storage battery via the power conversion device. In addition, the storage system receives the remote discharge command from the upper management server, discharges the power stored in the storage battery through the power conversion device, and supplies it to a predetermined power system. Further, the storage system receives a remote discharge command from the upper management server 2 and the communication with the management server is cut off during the discharge operation to the grid side, and the system voltage during the discharge operation becomes equal to or higher than the predetermined voltage In this case, control is performed to stop the discharge operation by the remote discharge command and switch to a predetermined operation.

  In the storage system according to the present embodiment, communication with the management server is interrupted during discharge operation to the grid side in response to a remote discharge command from the upper management server, and the system voltage during discharge operation is greater than or equal to a predetermined voltage When it becomes, control which stops the discharge driving | operation by remote discharge instruction | command, and switches to a predetermined | prescribed driving | operation is performed. Thereby, it is possible to suppress the system voltage V rising and becoming equal to or higher than the predetermined voltage to stabilize the system power and to suppress the generation of the power loss of the power generation device.

[One Example of Configuration of Power Storage System 1 According to Embodiment]
FIG. 1 is a diagram showing an example of a configuration of a power storage system 1 according to the embodiment. In the example of FIG. 1, the storage system 1 is provided in the home HM of the user (consumer), and consumes, for example, in the home HM the power generated by the solar panel PN (power generation device) installed on the roof , And can be stored in the storage battery 50.

  As shown in FIG. 1, the storage system 1 includes a solar panel PN, a connection box BX, a power conditioner 100, a controller 200, a storage battery 50, a distribution board DP, a power meter MT, and a home gateway. And 300. Further, in the storage system 1 shown in FIG. 1, the controller 200 is connected to the upper management server 2 via the home gateway 300 and the network N such as the Internet.

  The solar panel PN is an example of a power generation device capable of generating electric power based on natural energy. The solar panel PN is, for example, a solar cell module in which the required number of solar cell elements (cells) are arrayed and packaged by resin, tempered glass or the like, and is also called a solar panel. The cell used for the solar panel PN may be any cell. For example, various cells such as silicon-based cells, compound-based cells, and organic-based cells may be appropriately selected as the cells used for the solar panel PN according to the purpose. Further, although the present embodiment will be described using the solar panel PN as an example of the power generation device, the power generation device of the present embodiment is a solar light, as long as it can generate electric power using natural energy. It is not limited to the panel. The power generation device may be, for example, a device that generates electric power using gas, wind power, hydraulic power or the like. In addition, when a device that generates electric power using gas, wind power, water power or the like is used as a power generation device, power supply control is performed based on the timing of power generation start by the gas, wind power, water power or the like. In the following description, a solar power generation device is also referred to as a PV (Photovoltaic) device. The power generation apparatus may be directly connected to the grid outside the home. In this case, the power generation device is not controlled by the controller 200.

  The junction box BX is, for example, a device that collects the power generated by the solar panel PN. The junction box BX combines a plurality of wires from the solar panel PN into one and transmits it to the power conditioner 100. The connection box BX may be integral with the power conditioner 100.

  The power conditioner 100 is also referred to as a power conditioner or a PCS (Power Conditioning System). The power conditioner 100 is a power conversion device that makes the power transmitted from the solar panel PN via the connection box BX available to the electric device LD or the like in the house HM. For example, the power conditioner 100 converts DC power transmitted from the solar panel PN via the junction box BX into AC power. For example, after converting into AC power, the power conditioner 100 adjusts the power to an output corresponding to use in the house HM, charging of the storage battery 50, selling to the commercial power supply CP, and the like.

  The controller 200 controls charging / discharging by the power conditioner 100. Controller 200 also notifies the user of various information in power storage system 1 and accepts user's operation on power storage system 1. Further, the controller 200 is connected to the upper management server 2 via the home gateway 300 and the network N.

  Storage battery 50 is a secondary battery (battery) used in home HM. For example, storage battery 50 is charged by the power supplied from power conditioner 100. Also, for example, the storage battery 50 supplies the stored power to the electric device LD and the system power in the home HM via the power conditioner 100 and the distribution board DP. Storage battery 50 may be any battery as long as it can store electricity by charging and can be repeatedly charged and discharged. For example, as the storage battery 50, various storage batteries may be appropriately selected according to the purpose, such as a lithium ion battery, a lead battery, and a nickel hydrogen battery. The storage battery 50 may have any configuration as long as it has a function of storing electric power, and may be, for example, an electric car or a plug-in hybrid car.

  The distribution board DP is a device that divides electricity into the wiring of the house HM. For example, the distribution board DP includes various devices such as an earth leakage circuit breaker and a circuit breaker for wiring. For example, the distribution board DP supplies the power converted into alternating current by the power conditioner 100 to the electric device LD of the house HM, or the surplus of the power generated by the solar panel PN is the commercial power CP of the power company. Supply to Also, for example, the distribution board DP supplies the power supplied from the commercial power source CP to the electric device LD of the home HM at the time of purchase, ie, when receiving the power supply from the commercial power source CP.

  The power meter MT is a meter that measures the power supplied to the commercial power supply CP, that is, the power sold, and the power supplied from the commercial power CP, that is, the power purchased from the commercial power CP. For example, the power meter MT may include a meter that measures the sold power and a meter that measures the purchased power. For example, the power meter MT is provided between the distribution board DP and the commercial power supply CP, and measures the sold power or measures the purchased power.

  The home gateway 300 communicably connects between the in-home device of the storage system 1 and the external network N.

  The management server 2 is connected to the network N and manages the storage system 1. Management server 2 manages the energy control state of power storage system 1. Further, the management server 2 can receive a balance adjustment between energy consumption and other energy resources (not shown), and can instruct the electricity storage system 1 to instruct selling of electricity and restriction of purchasing electricity. For example, when there is a demand for grid power, the management server 2 transmits a remote discharge command instructing the storage system 1 to discharge the power stored in the storage battery 50. The remote discharge command includes the amount of discharge power and the discharge power.

[One Example of Configuration of Controller 200]
FIG. 2 is a diagram showing an example of the configuration of the controller 200 provided in the power storage system 1 according to the embodiment. In FIG. 2, among the configurations of the controller 200 according to the embodiment, only the configuration related to the discharge control process of the storage battery 50 is illustrated, and the configuration of the other controller 200 is omitted. As shown in FIG. 2, the controller 200 includes an output unit 210, an input unit 220, a communication unit 230, a control unit 240, and a storage unit 250.

  The output unit 210 may have a configuration and a function of displaying information by voice or image. For example, the output unit 210 may be a monitor that displays information, or may be a speaker that outputs information as sound. The output unit 210 outputs, for example, various information received from the power conditioner 100. For example, the output unit 210 displays information on the remaining amount of the storage battery 50. Further, the output unit 210 displays information on the connection state with the upper management server 2 and the management state of the upper management server 2.

  The input unit 220 receives an input according to an alert or a message output by the output unit 210. For example, the user can input an instruction for an alert or a message from the input unit 220. The input unit 220 is a device capable of receiving external input such as a keyboard, a touch panel, and a microphone. The controller 200 may be integrated with the power conditioner 100.

  Communication unit 230 is realized by, for example, a predetermined communication circuit or the like. For example, the communication unit 230 can communicate with the power conditioner 100 and the home gateway 300.

  The storage unit 250 is realized by, for example, a semiconductor memory device such as a random access memory (RAM) or a flash memory, or a storage device such as a hard disk or an optical disk. The storage unit 250 according to the embodiment has a predetermined voltage V1 and an operation log D1 as shown in FIG. The predetermined voltage V1 is a value less than the suppression voltage V2 of the system in which the power generation output to the system of the power generation device is suppressed. Although the predetermined voltage V1 is larger than the normal stable system voltage and smaller than the suppression voltage V2, it is preferable to have a value close to the suppression voltage V2 to predict that the system voltage V approaches the suppression voltage V2. The operation log D1 stores an operation log during discharge operation by the remote discharge command by the management server 2.

  The control unit 240 controls the operation and function of each unit of the power conditioner 100. The control unit 240 has an internal memory for storing programs defining various processing procedures and the like, and controls various processes. For example, the control unit 240 may be an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a central processing unit (CPU), a micro processing unit (MPU) or the like. In the example of FIG. 2, the request reception unit 241, the charge / discharge control unit 242, the communication connection state detection unit 243, and the operation log storage control unit 244 are included.

  The request receiving unit 241 receives requests from the input unit 220 and the management server 2. For example, the request receiving unit 241 receives a remote discharge command from the management server 2.

  The charge and discharge control unit 242 controls the charge and discharge processing of the power conditioner 100 according to the power generation state of the solar panel PN, the power consumption state of the load LD, and the storage state of the storage battery 50. Further, the charge / discharge control unit 242 performs discharge control from the storage battery 50 to the system according to the remote discharge command from the management server 2. Furthermore, charge / discharge control unit 242 receives a remote discharge command from management server 2 and shuts off communication with management server 2 during discharge operation to the grid side, and system voltage V during discharge operation is predetermined voltage V1. When it becomes above, the control which stops the discharge driving | operation by remote discharge instruction | command, and switches to a predetermined | prescribed driving | operation is performed. The predetermined operation is not the operation in the management state received the command from the management server 2, for example, as described above, the power generation state of the solar panel PN, the power consumption state of the load LD, the storage state of the storage battery 50 Is a normal operation that controls the charge / discharge processing of the power conditioner 100 in accordance with the above.

  The communication connection state detection unit 243 detects a communication connection state between the management server 2 and the controller 200. For example, when the home gateway 300 does not receive polling transmission that is sent to the controller 200 at predetermined intervals, the communication connection state detection unit 243 detects disconnection of communication. Further, communication confirmation is regularly performed between the home gateway 300 and the management server 2, and when communication between the home gateway 300 and the management server 2 is interrupted, the home gateway 300 communicates with the controller 200. Informs blocking. By this notification, the communication connection state detection unit 243 can detect interruption of communication.

  The operation log storage control unit 244 receives the remote discharge command from the management server 2 and interrupts the communication with the management server 2 during the discharge operation to the grid side, and then the operation log D1 recorded until the communication is recovered. Perform storage control of In addition, after the communication with the management server 2 is recovered, the operation log storage control unit 244 transmits the recorded operation log D1 to the management server 2.

[One Example of Discharge Control Processing Procedure of Storage Battery of Storage Battery 50 by Storage System 1]
FIG. 3 is a flowchart showing an example of a discharge control processing procedure of the storage battery 50 by the power storage system 1 according to the embodiment. As shown in FIG. 3, first, the request receiving unit 241 determines whether a remote discharge command for the storage battery 50 has been received from the management server 2 (step S101). When the remote discharge command has not been received (step S101, No), this determination process is repeated. On the other hand, when the remote discharge command is received (step S101, Yes), the charge / discharge control unit 242 discharges from the storage battery 50 the discharge power indicated by the remote discharge command to the system with the discharge power indicated by the remote discharge command. The operation is started (step S102).

  Thereafter, the communication connection state detection unit 243 determines whether the communication between the management server 2 and the controller 200 has been interrupted (step S103). When the communication is not interrupted (Step S103, No), it is further determined whether the discharge is completed (Step S104). If the discharge is not completed (No at Step S104), the process returns to Step S103. If the discharge is completed (Yes at Step S104), the present process is ended.

  On the other hand, when the communication is interrupted (Yes in step S103), the operation log storage control unit 244 starts storage of the operation log D1 (step S105). Thereafter, it is determined whether or not a predetermined time has elapsed (step S106). If the predetermined time has not elapsed (step S106, No), the determination process of step S106 is repeated. The predetermined time is, for example, a polling transmission interval to the controller 200 of the home gateway 300.

  If the predetermined time has elapsed (Yes at step S106), it is further determined whether the communication that has been blocked has recovered (step S107). If the communication is not recovered (step S107, No), it is further determined whether the system voltage V has become equal to or higher than the predetermined voltage V1 (step S108). If the system voltage V is not equal to or higher than the predetermined voltage V1 (No at Step S108), the discharge operation is continued, and the process returns to Step S107 to determine whether the communication has been recovered. The discharge operation is continued because the grid voltage V is less than the predetermined voltage V1 and there is a demand for grid power. In addition, since the power generation device such as the solar panel PN does not have the suppression voltage V2, the generation of the power generation loss can be suppressed. Further, in this case, the system voltage V is also in a stable state.

  On the other hand, if system voltage V is equal to or higher than predetermined voltage V1 (Yes at step S108), charge / discharge control unit 242 switches from the discharge operation to the predetermined operation (step S109), proceeds to step S107, and performs communication. Performs processing to determine whether or not it has recovered.

  If the communication is recovered (Yes at Step S107), the operation log storage control unit 244 notifies the management server 2 of the operation log D1 stored in the storage unit 250 (Step S110), and ends this processing.

  In this embodiment, communication with the management server 2 is interrupted during discharge operation to the grid side in response to a remote discharge command from the upper management server 2, and the system voltage V during discharge operation is equal to or higher than the predetermined voltage V1. When it becomes, the control which stops the discharge driving | operation by remote discharge command, and switches to a predetermined | prescribed driving | operation is performed. As a result, in the discharge operation when the communication is interrupted, the system voltage V is stopped before reaching the suppression voltage V2 and switched to the normal predetermined operation. For this reason, the grid voltage V does not rise to the suppression voltage V2, and while the grid power is stabilized, the power generation of the power generation apparatus is not suppressed and no power generation loss occurs.

  Further, in the present embodiment, by setting the predetermined voltage V1 to a predictive voltage close to the suppression voltage V2, the discharge operation can be continued as much as possible, and the system voltage V can be suppressed from reaching the suppression voltage V2. .

  Furthermore, in the present embodiment, the operation log D1 during the discharge operation by the remote discharge command is stored, and after communication with the management server 2 is recovered, the operation log D1 is notified to the management server 2. As a result, the management server 2 can reliably grasp information such as trouble during discharge operation.

  Further, in the present embodiment, when communication with the management server 2 is interrupted during discharge operation to the grid side in response to a remote discharge command from the upper management server 2, the discharge operation is continued for a predetermined time, and thereafter, When the system voltage V during discharge operation becomes equal to or higher than the predetermined voltage V1, control is performed to stop the discharge operation by the remote discharge command and to switch to the predetermined operation. By continuing the discharge operation for a certain period of time after the disconnection of the communication, the discharge operation corresponding to the remote discharge command can be stably performed. Further, even if the remote discharge command is received from the management server 2 and the discharge operation is performed to the system side, the increase of the voltage of the system can be suppressed independently. In the present embodiment, when communication with the management server 2 is interrupted, it is determined whether or not the system voltage V becomes equal to or higher than the predetermined voltage V1. After the discharge is started, it may be determined whether the system voltage V becomes equal to or higher than the predetermined voltage V1.

  While certain embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These embodiments can be implemented in other various forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and the equivalents thereof as well as included in the scope and the gist of the invention.

DESCRIPTION OF SYMBOLS 1 storage system 2 management server 50 storage battery 100 power conditioner 200 controller 210 output part 220 input part 230 communication part 240 control part 241 request reception part 242 charge / discharge control part 243 communication connection state detection part 244 operation log storage control part 250 storage part 300 home gateway BX connection box CP commercial power supply DP distribution board D1 operation log HM house LD electrical equipment (load)
MT power meter N network PN solar panel V grid voltage V1 specified voltage

Claims (5)

A storage battery for storing commercial power from at least a system;
A power conversion device for performing power conversion at the time of discharge and charge of the storage battery;
A control device that performs charge / discharge control of the storage battery;
A storage system comprising
The control device receives a remote discharge command from the upper management server, and the communication with the management server is interrupted during the discharge operation to the system side, and the system voltage during the discharge operation becomes equal to or higher than a predetermined voltage In this case, the storage system performs control of stopping the discharge operation by the remote discharge command and switching to a predetermined operation.   The storage system according to claim 1, wherein the predetermined voltage is a value less than a suppression voltage at which suppression of a power generation operation of a power generation device connected to the grid is started.   The power storage system according to claim 1 or 2, wherein the control device stores an operation log during discharge operation according to the remote discharge command, and notifies the management server of the operation log after communication with the management server is recovered.   When the control device receives a remote discharge command from the upper management server and the communication with the management server is interrupted during the discharge operation to the system side, the control device continues the discharge operation for a predetermined time, and then the discharge operation The storage system according to any one of claims 1 to 3, wherein control is performed to stop the discharge operation according to the remote discharge command and switch the operation to a predetermined operation when the system voltage in the storage voltage exceeds a predetermined voltage. A storage battery for storing commercial power from at least a system;
A power conversion device for performing power conversion at the time of discharge and charge of the storage battery;
A control device that performs charge / discharge control of the storage battery;
A storage battery discharge control method in a storage system comprising
The control device receives a remote discharge command from the upper management server, and the communication with the management server is interrupted during the discharge operation to the system side, and the system voltage during the discharge operation becomes equal to or higher than a predetermined voltage In this case, a storage battery discharge control method for performing control to stop the discharge operation according to the remote discharge command and switch to a predetermined operation.

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