Energy storage equipment

Abstract

This energy storage equipment comprises a plurality of energy storage elements connected in parallel, a plurality of management devices provided correspondingly to the plurality of energy storage elements, and a host device communicably connected to the plurality of management devices. The plurality of management devices include a first management device. The first management device includes a first communication unit, a first power supply unit that supplies power to the first communication unit, a first power supply line for supplying power from the first power supply unit to the first communication unit, and a first auxiliary power supply line for supplying power from a host power supply unit provided in the host device to the first communication unit.

Description

Power storage equipment

[0001] The present invention relates to power storage equipment.

[0002] In recent years, driven by the trend toward decarbonization, demand for storage batteries has been growing rapidly. Since storage batteries have a long service life, the reliability of the entire power storage equipment over a long period of time is required. Patent Document 1 discloses a power storage equipment (ESS: Energy Storage System) configured by modules in which a plurality of cells are connected in series, and banks in which a plurality of modules are connected in series.

[0003] The capacity of the entire power storage equipment is determined by the number of banks connected in parallel. Furthermore, each bank is equipped with a management device that controls and manages the cells, and the management device also performs communication between the banks. The management device includes a communication unit for performing communication between the banks, and a power supply unit that supplies electric power to the communication unit.

[0004] Japanese Unexamined Patent Application Publication No. 2020-20654

[0005] If the power supply unit in the management device fails, power cannot be supplied to the communication unit, and communication via the communication unit becomes impossible. As a result, communication with the bank managed by the management device cannot be performed, and there is a possibility that power cannot be supplied from the bank. As a result, a problem arises in that the required power supply and demand cannot be achieved from the power storage equipment.

[0006] An object of the present invention is to provide a power storage equipment that can achieve stable power supply and demand.

[0007] A power storage equipment according to one aspect of the present invention includes: a plurality of power storage elements connected in parallel; a plurality of management devices provided corresponding to the plurality of power storage elements; and a host device communicably connected to the plurality of management devices. The plurality of management devices include a first management device, and the first management device includes: a first communication unit; a first power supply unit that supplies power to the first communication unit; a first power supply line for supplying power from the first power supply unit to the first communication unit; and a first auxiliary power supply line for supplying power from a host power supply unit provided in the host device to the first communication unit.

[0008] According to the power storage equipment of the above aspect, stable power supply and demand can be achieved.

[0009] This is a diagram showing an overview of the remote monitoring system. This is a block diagram showing the internal configuration of the devices included in the remote monitoring system. This is a block diagram showing an example of the configuration of an energy storage system. This is a diagram showing an example of the configuration of a higher-level device and multiple management devices. This is a diagram showing an example of operation when the power supply unit of a management device fails. This is a diagram showing an example of operation in the case of a comparative example that does not have an auxiliary power line. This is a diagram showing a first example of a method for assigning identification information to a management device. This is a diagram showing a second example of a method for assigning identification information to a management device.

[0010] (1) The energy storage equipment comprises a plurality of energy storage elements connected in parallel, a plurality of management devices provided corresponding to the plurality of energy storage elements, and a higher-level device that is communicatively connected to the plurality of management devices, wherein the plurality of management devices includes a first management device, the first management device having a first communication unit, a first power supply unit that supplies power to the first communication unit, a first power line for supplying power from the first power supply unit to the first communication unit, and a first auxiliary power line for supplying power from a higher-level power supply unit provided in the higher-level device to the first communication unit.

[0011] The energy storage element may be an energy storage cell, an energy storage module, or a bank. The energy storage system may have multiple banks connected in parallel. A bank may have multiple energy storage modules connected in series, and an energy storage module may have multiple energy storage cells connected in series.

[0012] The energy storage system is connected to the power grid via a Power Conditioning System (PCS), and the energy cells in each bank are discharged to supply a predetermined amount of electricity to the power grid as stipulated in the contract. Conversely, the energy storage system's energy cells are charged to receive a predetermined amount of electricity from the power grid as stipulated in the contract. In this way, the energy storage system achieves the necessary power supply and demand.

[0013] The energy storage system comprises multiple management devices and a higher-level device that is communicatively connected to these multiple management devices. The higher-level device may be equivalent to a management device, or it may be a Power Management System (PMS) connected to a higher-level Energy Management System (EMS). The management devices are provided in accordance with the energy storage elements. The management devices are also called bank BMUs (Battery Management Units), and the higher-level device is also called an integrated BMU. The multiple management devices include a first management device.

[0014] The first management device includes a first communication unit and a first power supply unit that supplies power to the first communication unit. The first communication unit is responsible for communication between the first management device and the host device and other management devices. The first management device further includes a first power line for supplying power from the first power supply unit to the first communication unit and a first auxiliary power line for supplying power from a host power supply unit provided in the host device to the first communication unit.

[0015] Even if the first power supply unit fails to function due to a malfunction or other abnormality, and power is no longer supplied to the first communication unit from the first power line, power can still be supplied to the first communication unit from the higher-level power supply unit located in the higher-level device via the first auxiliary power line. This allows the first communication unit to continue operating and communicate with the higher-level device and other management devices. This prevents situations where communication with energy storage elements (e.g., banks) managed by the first management device becomes impossible, resulting in a loss of power supply from the banks, and thus ensures a stable power supply and demand.

[0016] (2) In the energy storage equipment described in (1) above, the plurality of control devices have a second control device, the second control device having a second communication unit, a second power supply unit that supplies power to the second communication unit, a second power line for supplying power from the second power supply unit to the second communication unit, and a second auxiliary power line for supplying power from the first power supply unit to the second communication unit.

[0017] The second control device includes a second communication unit and a second power supply unit that supplies power to the second communication unit. The second communication unit is responsible for communication between the second control device and other control devices. The second control device further includes a second power line for supplying power from the second power supply unit to the second communication unit and a second auxiliary power line for supplying power from the first power supply unit of the first control device to the second communication unit.

[0018] Even if the second power supply unit fails to function due to a malfunction or other abnormality, and power is no longer supplied to the second communication unit from the second power line, power can still be supplied to the second communication unit from the first power supply unit installed in the first management device via the second auxiliary power line. This allows the second communication unit to continue operating and communicate with other management devices. This prevents a situation where communication with energy storage elements (e.g., banks) managed by the second management device becomes impossible, resulting in a loss of power supply from the banks, thus ensuring a stable power supply and demand.

[0019] (3) In the energy storage equipment described in (1) above, when power is not supplied to the first communication unit via the first power line, and power is supplied to the first communication unit via the first auxiliary power line, the higher-level device assigns identification information to the first management device.

[0020] The higher-level device enables communication between itself and the first management device by supplying power from its power supply unit to the first communication unit via a first auxiliary power line. The higher-level device can assign identification information to the first management device. This identification information, for example, is a CANID if the communication protocol is CAN (Controller Area Network), and can identify the data content or the transmitting node. Message addressing using the ID allows the user to determine "what kind of data it is" or "whether it is data I will use," and enables setting a higher priority for important data.

[0021] When the number of energy storage elements managed by a control device is large, manually assigning identification information is time-consuming and inefficient. Since identification information can be automatically assigned from a higher-level device to the first control device, work efficiency can be improved.

[0022] (4) In the energy storage equipment described in (2) above, when power is not supplied to the second communication unit via the second power line, and power is supplied to the second communication unit via the second auxiliary power line, the first management device assigns identification information to the second management device.

[0023] The first management device enables communication between the first and second management devices by supplying power from the first power supply unit located in the first management device to the second communication unit via the second auxiliary power line. The first management device can assign identification information to the second management device.

[0024] When there are many energy storage elements managed by a control device, manually assigning identification information is time-consuming and inefficient. Since identification information can be automatically assigned from the first control device to the second control device, work efficiency can be improved.

[0025] The present invention will be specifically described with reference to the drawings illustrating its embodiments.

[0026] Figure 1 shows an overview of the remote monitoring system 100. The remote monitoring system 100 enables remote access to information regarding energy storage elements and power supply-related devices included in the mega solar power generation system S, thermal power generation system F, and wind power generation system W. Rectifiers (DC power supply devices or AC power supply devices) D installed in uninterruptible power supply (UPS) U, stabilized power supply systems for railways, etc., may also be remotely monitored.

[0027] A power conditioner (PCS) P and an energy storage system 101 are installed side-by-side in the mega solar power generation system S, the thermal power generation system F, and the wind power generation system W. The energy storage system 101 may be configured by installing multiple containers C containing groups of energy storage modules L side-by-side. Alternatively, the groups of energy storage modules L and the power conditioner P may be located inside a building (energy storage room). The groups of energy storage modules L include multiple energy storage elements. The energy storage elements are preferably rechargeable, such as secondary batteries like lead-acid batteries and lithium-ion batteries, or capacitors. Some of the energy storage elements may be non-rechargeable primary batteries.

[0028] In the remote monitoring system 100, a communication device 1 (see Figure 2) is installed / connected to each of the energy storage systems 101 or devices (P, U, D and the management device M described later) in the systems S, F, and W that are to be monitored. The remote monitoring system 100 includes the communication device 1, a server device 2 as an information processing device that collects information from the communication device 1, a client device 3 for viewing the collected information, and a network N which is a communication medium between the devices.

[0029] The communication device 1 may be a terminal device (measurement monitor) that communicates with a battery management unit (BMU) provided in the energy storage element to receive information about the energy storage element, or it may be an ECHONET / ECHONETLite® compatible controller. The communication device 1 may be an independent device, or it may be a network card type device that can be mounted on a power conditioner P or a group of energy storage modules L. One communication device 1 is provided for each group of energy storage modules in the energy storage system 101 in order to acquire information about the group of energy storage modules L. Multiple power conditioners P are connected to each other so as to enable serial communication, and the communication device 1 is connected to the control unit of one of the representative power conditioner P.

[0030] The server device 2 shown in Figure 1 includes a web server function and presents information obtained from the communication devices 1 installed on / connected to each monitored device in response to access from the client device 3.

[0031] Network N includes a public communication network N1, which is the so-called internet, and a carrier network N2 that implements wireless communication according to a predetermined mobile communication standard. The public communication network N1 includes a general optical line, and Network N includes a dedicated line to which the server device 2 is connected. Network N may also include an ECHONET / ECHONET Lite compatible network. The carrier network N2 includes a base station BS, and the client device 3 can communicate with the server device 2 via Network N from the base station BS. Access points AP are connected to the public communication network N1, and the client device 3 can send and receive information between the server device 2 and the access point AP via Network N.

[0032] In this manner, the remote monitoring system 100 utilizes communication devices 1 installed on or connected to each device under monitoring, and the server device 2 collects information such as the state of SOC and SOH (State of Health) of the energy storage elements in the energy storage system 101, as well as any abnormalities detected by each device. The collected information is presented collectively via the server device 2.

[0033] Figure 2 is a block diagram showing the internal configuration of the device included in the remote monitoring system 100. As shown in Figure 2, the communication device 1 comprises a control unit 10, a storage unit 11, a first communication unit 12, and a second communication unit 13. The control unit 10 is a processor using a CPU (Central Processing Unit), and it uses built-in memory such as ROM (Read Only Memory) and RAM (Random Access Memory) to control each component and execute processing.

[0034] The storage unit 11 uses non-volatile memory such as flash memory. The storage unit 11 stores a device program 1P that the control unit 10 reads and executes. The device program 1P includes a communication program compliant with SSH (Secure Shell), SNMP (Simple Network Management Protocol), etc. The storage unit 11 also stores information collected by the processing of the control unit 10, event logs, and other information. The information stored in the storage unit 11 can also be read via a communication interface such as USB, whose terminals are exposed on the housing of the communication device 1. The device program 1P stored in the storage unit 11 may be a copy of the device program 4P stored in the recording medium 4, read and stored in the storage unit 11.

[0035] The first communication unit 12 is a communication interface that enables communication between the communication device 1 and the monitored device to which it is connected. The first communication unit 12 uses a serial communication interface such as RS-232C or RS-485. For example, the power conditioner P is equipped with a control unit that has a serial communication function compliant with RS-485, and the first communication unit 12 communicates with that control unit. When the control boards provided in the energy storage module group L are connected by a CAN (Controller Area Network) bus and communication between the control boards is realized by CAN communication, the first communication unit 12 is a communication interface based on the CAN protocol. The first communication unit 12 may also be a communication interface that complies with the ECHONET / ECHONETLite standard.

[0036] The second communication unit 13 is an interface that enables communication via the network N, and uses a communication interface such as Ethernet (registered trademark) or a wireless communication antenna. The control unit 10 can communicate with the server device 2 via the second communication unit 13. The second communication unit 13 may also be a communication interface that conforms to the ECHONET / ECHONETLite standard.

[0037] In the communication device 1 configured in this way, the control unit 10 acquires measurement data for the energy storage element obtained from the device to which the communication device 1 is connected via the first communication unit 12. The control unit 10 may also function as an SNMP agent by reading and executing an SNMP program and respond to information requests from the server device 2.

[0038] The server device 2 uses a server computer and includes a control unit 20, a storage unit 21, and a communication unit 22. In this embodiment, the server device 2 is described as a single server computer, but processing may be distributed among multiple server computers.

[0039] The control unit 20 is a processor using a CPU or GPU (Graphics Processing Unit), and uses built-in memory such as ROM and RAM to control each component and execute processing. The control unit 20 performs communication and information processing based on the server program 21P stored in the storage unit 21. The server program 21P includes a web server program, and the control unit 20 functions as a web server that provides web pages to the client device 3. Based on the server program 21P, the control unit 20 collects information from the communication device 1 as an SNMP server.

[0040] The storage unit 21 uses, for example, non-volatile memory such as a hard disk or flash memory. The storage unit 21 stores the server program 21P and the data processing program 22P described above. The server program 21P and the data processing program 22P stored in the storage unit 21 may be copies of the server program 51P and the data processing program 52P stored in the recording medium 5, read out and stored in the storage unit 21.

[0041] The storage unit 21 stores measurement data of the power conditioner P and the power storage module group L of the power storage system 101 to be monitored, which is collected through processing by the control unit 20. The measurement data is associated with identification information (number) for identifying the power storage system 101 or the power conditioner P. The measurement data of the power storage module group L is stored in accordance with the hierarchical structure of domain, bank, module, or cell.

[0042] The storage unit 21 stores a plurality of images for displaying the states of the monitored power storage module group L or the devices P, U, D. The plurality of images are stored in the storage unit 21 in association with identification information for identifying the monitored power storage module group L or the devices P, U, D. The plurality of images include images representing the power storage module group L or the devices P, U, D.

[0043] The communication unit 22 is a communication device that implements communication connection and transmission / reception of information via the network N. Specifically, the communication unit 22 is a network card compatible with the network N.

[0044] The client device 3 is a computer used by operators such as managers or maintenance personnel of the power storage system 101 of the power generation systems S, F, W. The client device 3 may be a desktop or laptop personal computer, or may be a so-called smartphone or tablet communication terminal. The client device 3 includes a control unit 30, a storage unit 31, a communication unit 32, a display unit 33, and an operation unit 34.

[0045] The control unit 30 is a processor using a CPU. The control unit 30 causes the display unit 33 to display a web page provided by the server device 2 based on the client program 3P stored in the storage unit 31. The client program 3P is embedded in a web page provided by the web server function of the server device 2, includes a script temporarily stored in the client device 3 and a web browser program, and is a program for displaying a web-based screen based on operations in the server device 2.

[0046] The storage unit 31 uses, for example, a non-volatile memory such as a hard disk or a flash memory. Various programs including the client program 3P are stored in the storage unit 31. The client program 3P may be obtained by reading the client program 6P stored in the recording medium 6 and copying it into the storage unit 31.

[0047] The communication unit 32 uses a communication device such as a network card for wired communication, a wireless communication device for mobile communication connected to a base station BS (see FIG. 1), or a wireless communication device compatible with connection to an access point AP. The control unit 30 can perform communication connection and transmit / receive information to and from the server device 2 via the network N by means of the communication unit 32.

[0048] The display unit 33 uses a display such as a liquid crystal display or an organic EL (Electro Luminescence) display. The display unit 33 displays an image of a web page provided by the server device 2 through processing based on the client program 3P of the control unit 30. The display unit 33 is preferably a display with a built-in touch panel, but may also be a display without a built-in touch panel.

[0049] The operation unit 34 is a user interface such as a keyboard and a pointing device capable of inputting and outputting with the control unit 30, or a voice input unit. The operation unit 34 may use a touch panel of the display unit 33 or physical buttons provided on the housing. The operation unit 34 notifies operation information from a user to the control unit 30.

[0050] In the remote monitoring system 100 configured in this way, the server device 2 periodically acquires various information from the communication device 1, including the status of the power conditioner P, the energy storage module group L (management device M), the uninterruptible power supply U, and the rectifier D, based on the data processing program 22P, and stores it in the storage unit 21. The communication device 1 transmits status information for each energy storage module group L, with parent-child relationships linked according to the hierarchical structure. Based on the information acquired from the energy storage elements or each power supply-related device using the communication device 1, the server device 2 creates screen information (display information) that visually represents the status of the monitored system or device according to the hierarchical structure of the energy storage cells, and transmits it to the client device 3.

[0051] Figure 3 is a block diagram showing an example configuration of the energy storage system 101. The energy storage module group L may have a hierarchical structure consisting of energy storage modules (also called "modules") which are multiple energy storage elements (also called "energy storage cells" or "cells") connected in series, banks which are multiple modules connected in series, and domains which are energy storage facilities connected in parallel. In Figure 3, only one domain is shown for convenience. The energy storage system 101 is a large-scale ESS that includes multiple domains. Note that the energy storage elements may be energy storage cells, energy storage modules, or banks.

[0052] The energy storage system 101 includes a power conditioner (PCS) P. The power conditioner P supplies electricity generated by a power generation system such as a solar system to the energy storage system 101, and also supplies the electricity stored in the energy storage system 101 to other power consuming equipment (loads) or the power grid. The power conditioner P is connected to multiple parallel banks #1 to #N by power lines 42. A switch 43 is provided between the branching point of the power lines 42 to the multiple banks and the power conditioner P. The switching of the switch 43 switches the power supply from the power conditioner P to the entire domain on and off. The switch 43 may be provided inside the power conditioner P.

[0053] Each bank is provided with a circuit breaker 41. The circuit breaker 41 switches the power supply from the branching point of the power line 42 to the energy storage module group L on and off. The circuit breaker 41 switches between an ON state, where the power line 42 and the energy storage module group L are connected, and an OFF state, where they are not connected. With the energy storage module group L of each bank connected to the power line 42, charging or discharging, i.e., power supply, is performed to each energy storage module group L through the power conditioner P, switch 43, power line 42, and circuit breaker 41. In Figure 3, a circuit breaker 41 is provided for each bank, but multiple banks may be divided into groups, and one circuit breaker 41 may be provided for each group.

[0054] In the example shown in Figure 3, a management unit (BMU) M is provided for each bank and each domain. When explaining the management units M provided for each bank and each domain separately, the bank units are denoted with B and the domain units with D in parentheses for ease of explanation. The management unit (D) M is also called the higher-level unit. The management unit (D) M may be a device equivalent to the management unit (B) M, or it may be a PMS (Power Management System) connected to a higher-level EMS (Energy Management System). The management unit (D) M is also called the integrated BMU (Battery Management Unit). The management unit (B) M is also called the bank BMU (Battery Management Unit). The management units (B) M communicate via serial communication with the control boards (CMU: Cell Monitoring Unit) with communication functions that are built into each energy storage module. The control device M operates by receiving power from the power conditioner P or from the energy storage module group L via the power line 42.

[0055] Control device (B)M is connected to circuit breaker 41, and control device (D)M is connected to switch 43. Circuit breaker 41 and switch 43 are controlled by control device M, respectively.

[0056] Communication device 1 is connected to the group of energy storage modules L to be monitored via management device M. As described above, communication device 1 is connected to management device M via a serial communication cable by the first communication unit 12. Communication device 1 may be configured integrally with management device M. Communication device 1 operates by receiving power through a separate path from the power line 42. These multiple communication devices 1 are connected to each other to send and receive information. In the example shown in Figure 3, they are connected by a communication bus. The communication bus is, for example, a CAN cable. Alternatively, the communication bus may be a LAN cable or an ECHONET Lite compatible communication medium. Management device (D) M of a domain and management device (D) M of other domains in the same system may be connected by a different communication bus, for example a CAN bus, and may be able to communicate with each other. Management device M can control the circuit breaker 41 and the switch 43, respectively, based on instructions from communication device 1.

[0057] The communication device 1 connected to the management device (B)M of each bank, upon receiving instructions via the second communication unit 13, has the function of causing the battery module group L to perform a predetermined charge or discharge, and estimating the full charge capacity from the voltage and current measurements taken during that time.

[0058] The domain (energy storage facility) is connected to the power grid (generation grid, loads, etc.) via a power conditioner (PCS) P, and the energy storage elements in each bank are discharged to supply a predetermined amount of energy to the power grid as stipulated in the contract. Conversely, the energy storage elements in each bank are charged to receive a predetermined amount of energy from the power grid as stipulated in the contract. Discharging and charging of the energy storage elements is performed, for example, once to several times a day.

[0059] Next, we will describe the configuration of control device (D)M and control device (B)M. For convenience, in the following description, control device (D)M will be referred to as the higher-level device D, and control device (B)M will be referred to as control device B.

[0060] Figure 4 shows an example of the configuration of a higher-level device D and multiple management devices B. The higher-level device D includes a power supply unit 51 as a higher-level power supply unit, a microcontroller 52, and a communication unit 53 that communicates with the multiple management devices B. The power supply unit 51 supplies power (for example, 5V voltage) to the communication unit 53. The microcontroller 52 controls the operation of the power supply unit 51 and the communication unit 53.

[0061] The first control device, control device BNo. 1, includes a power supply unit 61 as the first power supply unit, a microcontroller 71, and a communication unit 81 as the first communication unit. The power supply unit 61 supplies power (5V voltage) to the communication unit 81. The microcontroller 71 controls the operation of the power supply unit 61 and the communication unit 81.

[0062] Management device BNo. 2, which serves as the second management device, includes a power supply unit 62 as the second power supply unit, a microcontroller 72, and a communication unit 82 as the second communication unit. The power supply unit 62 supplies power (5V voltage) to the communication unit 82. The microcontroller 72 controls the operation of the power supply unit 62 and the communication unit 82.

[0063] Furthermore, the Nth management device, Management Device BNo. N, comprises a power supply unit 6N as the Nth power supply unit, a microcontroller 7N, and a communication unit 8N as the Nth communication unit. The power supply unit 6N supplies power (5V voltage) to the communication unit 8N. The microcontroller 7N controls the operation of the power supply unit 6N and the communication unit 8N.

[0064] The control device BNo. 1 has a first power line L1 for supplying power from the power supply unit 61 to the communication unit 81, and a first auxiliary power line L2 for supplying power from the power supply unit 51 provided in the host device D to the communication unit 81. The first power line L1 is provided with a diode D1 for preventing reverse current. The first auxiliary power line L2 is provided with diodes D2 and D3 for preventing reverse current. The number of diodes provided in the first power line L1 and the first auxiliary power line L2 can be set as appropriate. Alternatively, switching elements such as FETs (Field-Effect Transistors) may be provided instead of diodes. By providing FETs, the voltage drop caused by diodes can be suppressed.

[0065] Control device BNo. 2 has a second power line L1 for supplying power from the power supply unit 62 to the communication unit 82, and a second auxiliary power line L2 for supplying power from the power supply unit 61 provided in control device BNo. 1 to the communication unit 82. The second power line L1 is provided with a diode D1 for preventing reverse current. The second auxiliary power line L2 is provided with diodes D2 and D3 for preventing reverse current. The number of diodes provided in the second power line L1 and the second auxiliary power line L2 can be set as appropriate. Alternatively, switching elements such as FETs (Field-Effect Transistors) may be provided instead of diodes. By providing FETs, the voltage drop caused by diodes can be suppressed. The same applies to control device BNo. N.

[0066] Communication unit 53, communication unit 81, communication unit 82, and communication unit 8N can communicate with each other using the CAN (Controller Area Network) protocol.

[0067] Power supply units 51, 61, 62, and 6N supply power to communication units 53, 81, 82, and 8N, respectively, but isolated power supplies (ISO power supplies) are used for insulation purposes. Isolated power supplies have their primary and secondary sides isolated because there is a risk of electric shock if leakage current or voltage from the power supply unit is applied to the communication lines connected to the communication units. For this reason, isolated power supplies have more components than non-isolated power supplies, and consequently, their failure rate is also higher.

[0068] Next, we will explain how the system operates when the power supply unit of control device B fails.

[0069] Figure 5 shows an example of operation when the power supply unit 62 of management device BNo. 2 fails. Power is supplied to the communication unit 82 of management device BNo. 2 from the power supply unit 62 via the second power line L1, and power is also supplied from the power supply unit 61 of management device BNo. 1 via the second auxiliary power line L2.

[0070] Even if the power supply unit 62 malfunctions or fails to function, and power is no longer supplied to the communication unit 82 from the second power line L1, power can still be supplied to the communication unit 82 from the power supply unit 61 provided in the first management device BNo. 1 via the second auxiliary power line L2, thus enabling the communication unit 82 to continue operating. The management device BNo. 2 can communicate with the higher-level device D and other management devices B. This prevents situations where communication with the energy storage elements (e.g., banks) managed by the management device BNo. 2 becomes impossible, resulting in a loss of power supply from the banks, and thus ensures a stable power supply and demand.

[0071] Furthermore, the communication unit 81 of the management device BNo. 1 is supplied with power from the power supply unit 61 via the first power line L1, and also supplied with power from the power supply unit 51 located in the host device D via the first auxiliary power line L2.

[0072] Even if the power supply unit 61 malfunctions or otherwise fails and power is no longer supplied to the communication unit 81 from the first power line L1, power can still be supplied to the communication unit 81 from the power supply unit 51 located in the host device D via the first auxiliary power line L2, thus enabling the communication unit 81 to continue operating. The management device BNo. 1 can communicate with the host device D and other management devices B. This prevents situations where communication with the energy storage elements (e.g., banks) managed by the management device BNo. 1 becomes impossible, resulting in a loss of power supply from the banks, and thus ensures a stable power supply and demand.

[0073] Figure 6 shows an example of operation in the case of a comparative example that does not have an auxiliary power line. The communication unit 81 of management device BNo. 1 is supplied with power only from the power supply unit 61. The communication unit 82 of management device BNo. 2 is supplied with power only from the power supply unit 62. The communication unit 8N of management device BNo. N is supplied with power only from the power supply unit 6N.

[0074] If the power supply unit 62 of management device BNo. 2 malfunctions or fails to function, power will no longer be supplied to the communication unit 82. As a result, the communication unit 82 will be unable to operate, and management device BNo. 2 will be unable to communicate with the higher-level device D and other management devices B. This will result in a loss of power supply from the bank, and consequently, the inability to supply the necessary power from the energy storage equipment. However, according to this embodiment, as explained in Figure 5, such problems do not occur.

[0075] Next, we will explain the assignment of identification information (automatic assignment). Identification information, for example, in the case of a CAN (Controller Area Network) communication protocol, is the CAN ID (address), which can identify the content of the data or the transmitting node. Message addressing using the ID allows you to determine "what kind of data it is" and "whether it is data I will use," and you can set a high priority for important data. The higher-level device D and the management device B need to be assigned unique identification information in order to communicate with each other. The assignment of identification information is performed once when the energy storage equipment is initially powered on.

[0076] Figure 7 shows a first example of a method for assigning identification information to management device B. Hereafter, the identification information will be described as CANID. The CANID of the host device is set to 1. In step S1, all power supply units 61, 62, ..., 6N of management device B are OFF, and the voltage 5V is not output. As a result, the communication units 81, 82, ..., 8N of all management device B are also stopped operating.

[0077] In step S2, the power supply unit 51 of the host device D is turned ON. As a result, in step S3, power is supplied to the communication unit 53 of the host device D, and power is also supplied to the communication unit 81 of the management device BNo. 1 via the first auxiliary power line L2, causing the communication units 53 and 81 to start operating and enabling communication. The host device D can assign CANID=2 to the management device BNo. 1.

[0078] As described above, the host device D enables communication between the host device D and the management device BNo. 1 by supplying power from the power supply unit 51 located in the host device D to the communication unit 81 via the first auxiliary power line L2. The host device D can assign identification information to the management device BNo. 1.

[0079] Figure 8 shows a second example of the method for assigning identification information to management device B. In Figure 8, it is assumed that management device BNo. 1 is assigned CANID = 2. In step S4, the microcontroller 71 of management device BNo. 1 outputs an enable signal to the power supply unit 61. As a result, in step S5, the power supply unit 61 turns from OFF to ON and outputs a voltage of 5V.

[0080] In step S6, power is supplied to the communication unit 82 of management device BNo. 2 from the power supply unit 61 via the second auxiliary power line L2. The communication unit 81 of management device BNo. 1 and the communication unit 82 of management device BNo. 2 start operating, and communication becomes possible. Management device BNo. 1 can assign CANID = 3 to management device BNo. 2. The same operation can be repeated up to management device BNo. N.

[0081] As described above, management device BNo. 1 supplies power from the power supply unit 61 located in management device BNo. 1 to the communication unit 82 of management device BNo. 2 via the second auxiliary power line L2, thereby enabling communication between management device BNo. 1 and management device BNo. 2. Management device BNo. 1 can then assign identification information to management device BNo. 2.

[0082] When there are many energy storage elements managed by a control device, manually assigning identification information is time-consuming and inefficient. Since identification information can be automatically assigned from the first control device to the second control device, work efficiency can be improved.

[0083] The identification information may be information used to identify the managed object (for example, the status data of the energy storage element) managed by the management device B, instead of the CANID.

[0084] The matters described in each embodiment can be combined with each other. Furthermore, the independent and dependent claims described in the claims can be combined with each other in any combination, regardless of the form of reference. In addition, the claims use a form in which claims referencing two or more other claims (multi-claim form), but are not limited to this. A form in which multi-claims referencing at least one multi-claim (multi-multi-claim) may also be used. For example, the capacity estimation method may be performed by a communication device or a management device instead of being performed by the server device 2.

[0085] 51, 61, 62, 6N Power supply unit 52, 71, 72, 7N Microcontroller 53, 81, 82, 8N Communication unit

Claims

1. An energy storage system comprising: a plurality of energy storage elements connected in parallel; a plurality of management devices provided corresponding to the plurality of energy storage elements; and a higher-level device communicated with the plurality of management devices, wherein the plurality of management devices include a first management device, the first management device having a first communication unit; a first power supply unit that supplies power to the first communication unit; a first power line for supplying power from the first power supply unit to the first communication unit; and a first auxiliary power line for supplying power from a higher-level power supply unit provided in the higher-level device to the first communication unit.

2. The energy storage equipment according to claim 1, wherein the plurality of management devices include a second management device, the second management device comprising: a second communication unit; a second power supply unit for supplying power to the second communication unit; a second power line for supplying power from the second power supply unit to the second communication unit; and a second auxiliary power line for supplying power from the first power supply unit to the second communication unit.

3. The energy storage equipment according to claim 1, wherein, while power is not supplied to the first communication unit via the first power line, and power is supplied to the first communication unit via the first auxiliary power line, the higher-level device assigns identification information to the first management device.

4. The energy storage equipment according to claim 2, wherein, while power is not supplied to the second communication unit via the second power line, and power is supplied to the second communication unit via the second auxiliary power line, the first management device assigns identification information to the second management device.

5. The energy storage equipment according to claim 1, wherein the first power line is equipped with a diode or switching element for preventing reverse current, and the first auxiliary power line is equipped with a diode or switching element for preventing reverse current.

6. The energy storage equipment according to claim 2, wherein the second power supply line is equipped with a diode or switching element for preventing reverse current, and the second auxiliary power supply line is equipped with a diode or switching element for preventing reverse current.

7. The energy storage equipment according to claim 1, wherein the first communication unit is supplied with power from the first power supply unit via the first power line and also supplied with power from the higher-level power supply unit via the first auxiliary power line.

8. The energy storage equipment according to any one of claims 1 to 7, comprising a communication device provided one for each of the multiple energy storage elements, for acquiring information about the energy storage elements.

9. The energy storage equipment according to claim 8, wherein the communication device causes the energy storage element to perform a predetermined charge or discharge and estimates the full charge capacity from the voltage and current measurements taken during that time.

10. Energy storage equipment according to any one of claims 1 to 7, comprising a power conditioner, a power line, and a switch, wherein the power conditioner is connected to a plurality of energy storage elements in parallel by the power line, and the switch is provided between the branching point of the power line to the plurality of energy storage elements and the power conditioner.

11. The energy storage equipment according to claim 10, wherein a circuit breaker is provided for each of the energy storage elements, and the circuit breaker switches the power supply from the branching point of the power line to the plurality of energy storage elements to the energy storage elements on and off.

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