Distributed energy storage control system and program online upgrading method thereof

Abstract

The invention relates to the technical field of energy storage control systems, and discloses a distributed energy storage control system and a program online upgrading method thereof.The system comprises a battery stack control layer, a battery cluster control layer and a battery module control layer which are in optical fiber communication connection in sequence, the main control board of the cell stack control layer can complete upgrading of each board card of the whole energy storage system by adopting one Ethernet interface, remote operation is realized without going to the field, and the operation is simple, convenient and efficient; each control layer can adopt a case design, and a high-speed LVDS (Low Voltage Differential Signaling) back bus is adopted in a case, so that high-speed communication link support is provided for data sharing among board cards in the case. The control system adopts a layered design, high-speed optical fiber communication is adopted between control layers, and the control system has obvious high-speed data transmission capability and extremely high anti-interference capability. According to the program upgrading method, two data communication modes of point-to-point framing transmission and broadcast framing transmission are adopted, respective advantages are fully exerted, and reliability and high efficiency of program upgrading are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage control systems, and in particular to a distributed energy storage control system and an online program upgrade method thereof. Background Art

[0002] The electrochemical energy storage system includes single cells, battery modules, battery clusters and battery stacks. The control of the entire system is relatively complex. From top to bottom, it requires multiple boards and multiple processors (such as ARM, FPGA and DSP, etc.) for coordinated control. There are many problems in program upgrades. In addition, most existing energy storage systems adopt distributed board layouts, and communications use many different communication media and protocols such as 485, Modbus, Ethernet, etc., with low communication efficiency and weak anti-interference ability. The existing program upgrade methods are often either only local optimizations or not universal, that is, they are not feasible for most manufacturers.

[0003] At present, some manufacturers have proposed some program upgrade methods for energy storage control systems. For example, a patent application with Chinese patent application number 202310416253.6 discloses a method for upgrading software of energy storage system equipment. The control module and the software in the battery pack of the energy storage system can be upgraded through a communication module. However, this method has three main problems: First, this method is limited to upgrading the boards at the BMU level, and the BCMU and above levels cannot be upgraded, which has certain limitations. Second, it is necessary to lay multiple cables for upgrading the program connected to the BMU in advance and aggregate them somewhere, which may increase the system cost. Third, the program upgrade requires people to carry the communication module to the site, connect the communication module and upgrade the battery cluster modules one by one. Remote automatic upgrades cannot be achieved, and the degree of automation is relatively low. For example, Chinese patent application numbers 202410206470.7 and 202110640216.4 both rely on EMS to provide a proprietary interface for upgrading the energy storage system program. This approach is not feasible for most energy storage manufacturers. There are two main reasons. First, most current energy storage projects, especially large-scale energy storage projects, have EMS and battery stacks, i.e., control systems, which are independently tendered. It is almost impossible for EMS to provide a universal program upgrade interface compatible with the control systems of many battery stack manufacturers. Second, EMS is relatively complex, and battery stack manufacturers will not invest too much manpower to develop EMS, and will not use EMS to upgrade the system program.

[0004] In summary, the existing methods for upgrading energy storage control systems and programs have certain problems: First, different boards use different interfaces, special burning software and tools, which require operation and maintenance personnel to install a lot of software, be familiar with different interface wiring and master complex software operation steps, which is cumbersome and error-prone; second, personnel need to arrive at the project site, often need to open the cabinet door, remove the shell, connect cables and connect proprietary tools, especially BMU (Battery Management Unit) installed in the battery box, disassembling parts can easily cause equipment damage, which puts high demands on on-site operations and greatly reduces the maintainability of the system; third, the energy storage system has a large number of control boards. Taking a 100MW / 400MWh project as an example, the battery control system has 17,280 BMU boards, 1,080 BCMU (Battery Cluster Control Unit) boards, 60 battery stack-level control boards and several other control boards. Manually upgrading the boards one by one consumes manpower and time that is not allowed during the construction period. Summary of the invention

[0005] The purpose of the present invention is to provide a distributed energy storage control system and its program online upgrade method, optimize the communication architecture of the energy storage control system, improve communication efficiency, realize remote online program upgrade of various control panels, reduce the complexity of on-site operation and maintenance and save costs, while ensuring the reliability and efficiency of program upgrades, and providing technical support for the reliable and stable operation of the energy storage system.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A distributed energy storage control system comprises a battery stack control layer, a battery cluster control layer, and a battery module control layer connected in sequence by optical fiber communication;

[0008] The battery stack control layer includes a main control box and a main control board arranged in the main control box, and the main control board is provided with an Ethernet interface, and the Ethernet interface is used for communication connection with a remote control terminal;

[0009] The battery cluster control layer includes a plurality of cluster control boxes and a BCMU control board arranged in the cluster control box, and the plurality of BCMU control boards are connected to one main control board through optical fiber communication;

[0010] The battery module control layer includes multiple battery module control systems, each battery module control system includes multiple BMU control boards, and the multiple BMU control boards are electrically connected to the multiple battery modules in a one-to-one correspondence; each battery module control system corresponds to a BCMU control board, and the multiple BMU control boards in each battery module control system are respectively connected to the corresponding BCMU control boards in optical fiber communication.

[0011] Furthermore, the main control chassis and the cluster control chassis are in the form of containers, and the boards in the main control chassis and the cluster control chassis share a high-speed LVDS back bus.

[0012] Furthermore, the control chassis is also provided with a power board, a PCS board, an IO board, and a sampling board which are electrically connected to the main control board.

[0013] Furthermore, the cluster control chassis is also provided with a power supply board, an IO board, and a plurality of optical fiber boards electrically connected to the BCMU control board, and the optical fiber board is used for optical fiber communication connection with the BMU control board.

[0014] Furthermore, the remote control terminal is a web client installed on an operator workstation or an operation and maintenance computer, and a user accesses the Ethernet interface through a web browser of the operator workstation or the operation and maintenance computer.

[0015] The present invention also provides a method for online program upgrade of a distributed energy storage control system, which uses the above-mentioned distributed energy storage control system, wherein the distributed energy storage control system adopts a point-to-point frame transmission mode and a broadcast frame transmission mode to forward the program;

[0016] Point-to-point frame transmission is used for program upgrades between different boards in the chassis. Each frame message sent by the sending board requires a response from the target board, and has a timeout retransmission mechanism.

[0017] The broadcast frame transmission method is used when there are many target boards with the same program type. The sending board periodically divides the program into frames and sends it. No response from the target board is required in the middle. After sending, it will wait for the upgrade result of the target board. If there are still target boards that have not completed the upgrade within a certain time interval, a broadcast retransmission will be performed.

[0018] Furthermore, in the program online upgrade method, program forwarding adopts an internal private protocol, and the format of the internal private protocol includes a frame header, program level, program type, program version number, frame sequence number, total number of frames, total program length, and program CRC. When point-to-point frame transmission and broadcast frame transmission are used for program forwarding, it has frame transmission, packet loss retransmission, and verification mechanisms.

[0019] Furthermore, the program online upgrade method includes a program upgrade method between a web client and a main control box main control board; the program upgrade method between a web client and a main control box main control board specifically includes:

[0020] (1) Enter your username and password in the web client to log in;

[0021] (2) Enter the upgrade program interface, select the program level and program type to be upgraded. The program level includes three levels, corresponding to the battery stack control layer, battery cluster control layer, and battery module control layer respectively. The program type corresponds to the type code of each board. Enter the version number of the new program, and then load the corresponding file to the web client.

[0022] (3) The web client calculates the CRC of the new program and sends the new program file along with the program level, program type, program size, version number and CRC value to the main control board of the main control chassis through the HTTP protocol;

[0023] (4) The program upgrade receiving module of the main control board is responsible for receiving the new program. After receiving the program upgrade instruction, the received new program file is placed in the system temporary path and CRC calculation is performed on the new program file. If the calculated CRC value is the same as the CRC value received by the protocol, the program transmission is considered to be correct. Otherwise, the file transmission is considered to be wrong and the file transmission result is sent to the server.

[0024] (5) When the program transmission is correct, the program upgrade receiving module of the main control board notifies the program upgrade processing module of the main control board, and the program upgrade processing module performs the program upgrade operation;

[0025] (6) The program upgrade receiving module of the main control board waits for the upgrade success or failure result sent by the program upgrade processing module, and sends the result to the web client.

[0026] Furthermore, the program online upgrade method also includes a main control board program upgrade method; the main control board program upgrade method specifically includes:

[0027] (1) After receiving the program receiving success status sent by the program upgrading receiving module of the main control board, the program upgrading processing module of the main control board determines whether the current energy storage system is in operation. If so, the main control board switches the energy storage system to the upgrading mode. In the upgrading mode, the energy storage system rejects any external charging and discharging instructions;

[0028] (2) Determine the target control layer and target board based on the program level and program type:

[0029] When the target control layer is the battery stack control layer, and the target board is the main board, determine whether the version number of the new program is the same as the version number of the old program. If they are not the same, back up the old program, then load the new program into the program area of ​​the main board, start the upgrade, if the upgrade is successful, save the version number of the new program, if the upgrade fails, start the backed up old program, and transmit the upgrade result to the program upgrade receiving module of the main control board;

[0030] When the target control layer is the battery stack control layer, and the target board is a non-main control board, the main control board forwards the new program to the target board using a point-to-point frame transmission method, and starts the upgrade, waiting for the target board to feedback the upgrade result and sending the upgrade result to the program upgrade receiving module of the main control board; the number of the non-main control boards is unique and there are no boards with the same program type;

[0031] When the target control layer is not the battery stack control layer, the main control board sends the new program to the BCMU control board using broadcast frame transmission. The BCMU control board starts the BCMU control board program upgrade method, waits for the target board to feedback the upgrade result and sends the upgrade result to the program upgrade receiving module of the main control board.

[0032] Furthermore, the program online upgrade method also includes a BCMU control board program upgrade method; the BCMU control board program upgrade method specifically includes:

[0033] (1) After the BCMU control board receives the new program sent by the main control board, it determines the target control layer and target board according to the program level and program type:

[0034] (2) When the target control layer is the battery cluster control layer and the target board is the BCMU control board, determine whether the version number of the new program is the same as the version number of the old program. If they are not the same, back up the old program, then load the new program into the program area of ​​the BCMU control board, start the upgrade, if the upgrade is successful, save the version number of the new program, if the upgrade fails, start the backed-up old program, and upload the upgrade result to the main control board;

[0035] (3) When the target control layer is the battery cluster control layer, and the target boards are multiple identical fiber boards, the BCMU control board uses a broadcast frame transmission method to send the new program to multiple identical fiber boards. When the version number of the new program is different from the version number of the old program, the fiber board starts the upgrade. If the upgrade is successful, the version number of the new program is saved. If the upgrade fails, the backup old program is started and the upgrade result is transmitted to the BCMU control board.

[0036] (4) When the target control layer is the battery cluster control layer, and the target board is neither the BCMU control board nor the fiber board, but is the only other board, the BCMU control board uses point-to-point frame transmission to forward the new program to the target board, starts the upgrade, waits for the target board to feedback the upgrade result, and sends the upgrade result to the BCMU control board;

[0037] (5) When the target control layer is the battery module control layer, the BCMU control board uses broadcast frame transmission to send the new program to the BMU control board. The BMU control board starts the upgrade and sends the upgrade result to the BCMU control board.

[0038] Furthermore, the steps of implementing program upgrade by adopting point-to-point frame transmission mode for program forwarding are as follows:

[0039] First, the sending side card calculates the number of frames to be sent according to the length of the upgraded new program, fills and sends the first frame message according to the upgraded frame format;

[0040] Secondly, the sending side card waits for the target card to feed back a response message with a period of time T1. If the frame number of the received response message is 8888, it means that the new program version number is the same as the old program version number and no upgrade is required. By default, the program upgrade is successful and the result is sent to the sending side card;

[0041] Again, if the frame number of the received response message is not 8888, and this response message is the last frame response message, the program upgrade is successful and the result is sent to the sending side board; then, if the frame number of the received response message is not 8888, and this response message is not the last frame response message, continue to organize the next frame upgrade message and send it to the target board;

[0042] Then, if the sending side board card does not receive the response message from the target board card after exceeding the T1 time interval, the sending side board card will resend;

[0043] Finally, if the sending side board still does not receive a response message from the target board after the T2 time interval, the sending side board defaults to program upgrade failure and sends the upgrade result to the sending side board, where T2>T1.

[0044] Furthermore, the steps of performing program forwarding in the broadcast frame transmission mode and implementing program upgrade are as follows:

[0045] First, the sending side card calculates the number of frames to be sent according to the length of the new program to be upgraded, fills the message according to the upgraded frame format and sends it, and continues to organize and send the next frame message after the timing is reached until the entire new program is sent;

[0046] Secondly, the sending side card waits for the target card to send a response message with a period of time T1. If the frame number of the received response message is 8888, it means that the new program version number is the same as the old program version number and no upgrade is required. The target card ID number is recorded.

[0047] Again, if the frame number of the received response message is not 8888, the upgrade of the target board fails and the ID number is recorded; then, if the received response message is not the response message of the last target board, continue to listen to the response message of the next target board;

[0048] Then, if the sending side board card does not receive all the target board card response messages within the T1 time interval but not exceeding the T2 time interval, it will rebroadcast the new program file starting from frame 1; where T2>T1;

[0049] Finally, if the sending side board has not received all the target board response messages within the T2 time interval, it will count the target boards that have not received the response messages based on the recorded target board ID numbers and send the upgrade results to the sending side board.

[0050] According to the specific embodiments provided by the present invention, the distributed energy storage control system and the method for online program upgrade provided by the present invention disclose the following technical effects:

[0051] First, the distributed energy storage control system adopts a three-layer control architecture, optimizes the communication architecture of the energy storage control system, improves communication efficiency, and adopts high-speed optical fiber communication between control levels to achieve high-speed data communication and high anti-interference ability of the energy storage control system. In addition, the chassis design is adopted, and the high-speed LVDS back bus is used in the chassis, which provides high-speed communication link support for data sharing between boards in the chassis, greatly improving the convenience of energy storage system control protection and the efficiency of program upgrades; secondly, the program upgrade method adopts two data communication methods, point-to-point frame transmission and broadcast frame transmission, giving full play to their respective advantages. The data transmission is guaranteed by a strict private protocol (frame transmission, packet loss retransmission and strict verification mechanism), and the program upgrade achieves extremely high reliability and efficiency; finally, the program upgrade method can complete the program upgrade of all functional boards such as BMU, BCMU, stack controller, PCS, etc. of the entire energy storage system through only one Ethernet interface, and can be completely remotely operated without going to the site or any other operations, making the energy storage system program upgrade simple and efficient.

[0052] In summary, the present invention simplifies and unifies the external interface of the energy storage system program upgrade, improves the efficiency and reliability of the energy storage system program upgrade, improves the system data transmission efficiency and anti-interference ability, reduces the complexity of on-site operation and maintenance, reduces personnel business trips and reduces enterprise costs, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0054] Figure 1 This is a schematic diagram of the structure of a distributed energy storage control system according to an embodiment of the present invention;

[0055] Figure 2 Schematic diagram of the chassis and back bus structure of the embodiment of the present invention, wherein (a) is the main control chassis, and (b) is the cluster control chassis;

[0056] Figure 3 This is a flowchart of a program upgrade between a web client and a main control board of a main control chassis according to an embodiment of the present invention;

[0057] Figure 4 This is a logic flow chart of the main control board program upgrade according to an embodiment of the present invention;

[0058] Figure 5 This is a logical flow chart of the BCMU control board program upgrade according to an embodiment of the present invention.

[0059] Figure 6 This is a schematic diagram of a point-to-point frame transmission message format according to an embodiment of the present invention;

[0060] Figure 7 This is a logic flow chart of the point-to-point frame transmission upgrade program according to an embodiment of the present invention.

[0061] Figure 8 A schematic diagram of a broadcast frame transmission message format according to an embodiment of the present invention;

[0062] Fig. 9 The present invention is a logical flow chart of the broadcast frame transmission upgrade program according to an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] The purpose of the present invention is to provide a distributed energy storage control system and a method for online program upgrade thereof. First, an Ethernet interface is used to complete the program upgrade of the entire energy storage system including all functional boards such as BMU, BCMU, stack controller, PCS, etc., and it can be operated completely remotely, without going to the site, and without any other operations, which is simple and efficient; second, two data communication methods, point-to-point frame transmission and broadcast frame transmission, are adopted to give full play to their respective advantages. The data transmission adopts a strict private protocol as escort, which ensures the reliability and efficiency of program upgrade; third, the control system adopts a chassis mode, and the chassis adopts a high-speed LVDS back bus, which provides high-speed communication link support for data sharing between boards in the chassis, which greatly improves the convenience of control and protection of the energy storage system and the efficiency of program upgrade; fourth, a layered design is adopted, the functions of the three control layers are clearly divided, and high-speed optical fiber communication is adopted between the control layers, which has obvious high-speed data transmission capability and extremely high anti-interference ability in harsh energy storage application environments.

[0065] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0066] like Figure 1-Figure 2 As shown, the distributed energy storage control system provided by the present invention is divided into three layers from top to bottom. The first layer is the battery stack control layer, which is responsible for system coordination control, battery stack power conversion, system external communication and control protection, etc. The second layer is the battery cluster control layer, which is responsible for battery cluster control protection, data acquisition, auxiliary equipment communication and upper and lower control layer communication, etc. The third layer is the battery module control layer, which is responsible for battery module power device control protection, battery module parameter acquisition, battery cluster control layer communication, etc.

[0067] The battery stack control layer, the battery cluster control layer, and the battery module control layer are connected in sequence by optical fiber communication.

[0068] The battery stack control layer includes a main control chassis and a main control board arranged in the main control chassis. The main control board is provided with an Ethernet interface, and the Ethernet interface is used for communicating with a remote control terminal. The user can remotely access the operator workstation or the operation and maintenance computer to access the Ethernet through a web browser to realize the program upgrade of all boards and cards of the three-level control layer from top to bottom of the entire control system, without installing any burning software, opening the cabinet door, disassembling parts, connecting any proprietary tools, and arriving at the site. The operation is simple and the system is highly maintainable.

[0069] The control box is also provided with a power board, a PCS board, an IO board, and a sampling board that are electrically connected to the main control board. The sampling board in the main control box collects the three-phase line voltage and three-phase current on the grid side, which are used to calculate the active power, reactive power, frequency, power factor, charge and discharge power, etc. of the energy storage system; the IO board in the main control box collects the system emergency stop signal, circuit breaker, DC disconnect switch status, grounding knife status, access control status, etc., and outputs the control system fault indicator light, disconnect switch, circuit breaker opening and closing, etc.

[0070] The battery cluster control layer includes multiple cluster control chassis and BCMU control boards arranged in the cluster control chassis. The multiple BCMU control boards are connected to one main control board by optical fiber communication. The cluster control chassis is also provided with a power supply board, an IO board, and multiple optical fiber boards electrically connected to the BCMU control board. The optical fiber board is used to connect to the BMU control board by optical fiber communication. The sampling board in the cluster control chassis: collects the battery cluster voltage, battery cluster current, etc., for calculating the battery cluster charge and discharge power, charge and discharge quantity, etc.; the IO board in the cluster control chassis: collects the switch status of the container auxiliary circuit, the positive and negative switches of the battery cluster, the access control switch, the pre-charge contactor, the liquid cooling unit fault input, the fire alarm dry contact, the fan status, etc., and outputs control of the DC circuit breaker, the positive and negative switches of the battery cluster, the cluster fault indicator light, the auxiliary circuit switch, the pre-charge contactor, the fan drive, etc.

[0071] The battery module control layer includes multiple battery module control systems, each battery module control system includes multiple BMU control boards, and the multiple BMU control boards are electrically connected to the multiple battery modules in a one-to-one correspondence; each battery module control system corresponds to a BCMU control board, and the multiple BMU control boards in each battery module control system are respectively connected to the corresponding BCMU control boards in optical fiber communication.

[0072] In the energy storage system in the embodiment of the present invention, multiple battery modules form a battery cluster, and multiple battery clusters form a battery stack.

[0073] like Figure 2 As shown, the main control chassis and the cluster control chassis are in the form of containers, and the boards in the main control chassis and the cluster control chassis share a high-speed LVDS back bus.

[0074] The boards of the battery stack control layer and the battery cluster control layer are integrated in the control chassis of the corresponding levels. The boards in the chassis share a powerful high-speed LVDS back bus, and high-speed optical fiber communication is used between the three control levels. This can quickly and reliably realize the upgrade and data sharing of the boards in the horizontal chassis and between the vertical chassis, and the control system can easily expand new boards.

[0075] like Figure 3-Figure 9As shown, the present invention also provides a method for online program upgrade of a distributed energy storage control system, which uses the above-mentioned distributed energy storage control system, and the distributed energy storage control system adopts a point-to-point frame transmission mode and a broadcast frame transmission mode to forward the program;

[0076] Among them, the point-to-point frame transmission method is used for program upgrades between boards inside the chassis. Each frame message sent by the sending side board requires a response from the target board, and has a timeout retransmission mechanism to ensure the program integrity of this method; the broadcast frame transmission method is used for target boards with a large number of boards with the same program type (such as the BMU board on the third layer, the fiber optic board on the second layer, etc.). The sending side board sends the program in frames at a fixed period, and no response from the target board is required in the middle. After sending, it will wait for the upgrade result of the target board. If there is still a target board that has not completed the upgrade within a certain time interval, a broadcast retransmission will be performed. This can not only meet the reliability of the program upgrade, but also greatly improve the efficiency of the program upgrade.

[0077] Among them, the program upgrades of the boards within the chassis and between the chassis of the distributed energy storage control system all adopt internal private protocols. The protocol format includes frame header, program level, program type (board type), program version number, frame sequence number, total number of frames, total program length, program CRC, etc. When point-to-point and broadcast transmission are adopted, it has packet loss retransmission, communication recovery and continuation as well as strict verification mechanisms to ensure the reliability and efficiency of program upgrades.

[0078] The following is a detailed description of the upgrade solutions for each control layer and target board involved in the present invention:

[0079] 1. Program upgrade between web client and main control board of main control chassis

[0080] like Figure 3 As shown in the figure, the program upgrade method between the web client and the main control board of the main control chassis is as follows:

[0081] First of all, considering security issues, you need to enter your username and password to log in;

[0082] Secondly, enter the dedicated upgrade program interface, select the program level to be upgraded (1 represents the first level, 2 represents the second level, and 3 represents the third level), the program type (each board has a different type code), enter the version number of the new program, then load the corresponding file to the web server, and finally click the program upgrade button;

[0083] Thirdly, the web client will perform CRC calculation on the program and send the program file together with the program level, program type, program size, version number and CRC value to the main control board (i.e. web server) of the main control chassis through the http protocol;

[0084] Then, the "program upgrade receiving module" of the main control board is responsible for receiving the new program. After receiving the program upgrade instruction, it will put the received program file into the system temporary path (under the operating system file system) and perform CRC calculation on the file. If the calculated CRC value is the same as the CRC value received by the protocol, it is considered that the program transmission is correct. Otherwise, it is considered that the file transmission is wrong and the file transmission result is sent to the server.

[0085] Then, if the CRC is correct, the "Program Upgrade Receiving Module" will notify the "Program Upgrade Processing Module", which will perform program upgrade related operations;

[0086] Finally, the "program upgrade receiving module" will wait for the upgrade success or failure result sent by the "program upgrade processing module" and send the result to the web client.

[0087] 2. Main control board program upgrade

[0088] The main control board is the main entry point for program upgrades of the entire energy storage system. Figure 4 This is the logic flow chart of the main control board program upgrade. The main control board program upgrade method is as follows:

[0089] First, after receiving the successful program reception status sent by the "program upgrade receiving module" of the main control board, it will be determined whether the current energy storage system is in operation. Only when the system is in a non-operating state can the program be upgraded. Among them, the method for determining whether the energy storage system is in operation can be: the main control board determines the current energy storage system operation status by reading the working status of the power conversion unit shared by the energy storage converter PCS (the PCS power conversion unit will share the system operation status, fault and other data to the main control board through the chassis back bus);

[0090] Secondly, the main control board will switch the energy storage system to "upgrade mode", in which the energy storage system rejects any external charging and discharging instructions;

[0091] Next, when it is determined that the target board is the first-layer main control board, first determine whether the version number of the new program is different from the version number of the old program. If the two are different, the old program will be backed up, and then the new program will be loaded into the program area, the upgrade will be started and the upgrade indicator will be lit. If the upgrade is successful, the version number will be saved. If the upgrade fails, the backed-up old program will be started, and the upgrade result will be notified to the "program upgrade receiving module";

[0092] Then, when the target board to be upgraded is a non-main control board in the first layer, the main control board uses point-to-point frame transmission to transmit the new program to be upgraded to the target board and start the upgrade (see the transmission logic). Figure 7 ), wait for the target board to feed the upgrade result and send the upgrade result to the "program upgrade receiving module" of the main control board;

[0093] Finally, when the target board is determined to be non-first-layer, the main control board first sends the new program to the BCMU control board in the form of broadcast frame transmission (see the transmission logic). Fig. 9 ), the BCMU control panel starts the corresponding program upgrade process (see Figure 5 ), wait for the program upgrade result, and send the result to the main control board "program upgrade receiving module". Among them, there are multiple BCMU control boards in the second layer, and the broadcast frame transmission method is used to improve the upgrade efficiency.

[0094] 3. BCMU control board program upgrade

[0095] The BCMU control panel is the main entry point for upgrading the second and third layer programs of the entire energy storage system. Figure 5 This is the logical flow chart for upgrading the BCMU board program. The method for upgrading the BCMU control board program is as follows:

[0096] First, determine whether the upgraded new program has been completely received;

[0097] Secondly, when the program type is BCMU control board, if the version number of the new program is the same as the version number of the old program, exit the upgrade (default upgrade success). When the version number of the new program is different from the version number of the old program, load the new program into the program area of ​​the BCMU control board, start the upgrade and light up the upgrade indicator. If the upgrade is successful, save the version number of the new program. If the upgrade fails, start the backed-up old program and send the upgrade result to the main control board.

[0098] Again, when the program type is not a BCMU control board, and the target board is not a third-layer program type nor a fiber board, the upgrade program is transmitted to the target board in a point-to-point frame transmission mode and the upgrade is started (see the point-to-point frame transmission logic). Figure 7 ), wait for the target board to feed the program upgrade result, and send the upgrade result to the BCMU control board;

[0099] Then, when the target board is a third-layer board or the program type is a fiber board, the upgrade program is transmitted to the fiber board in a broadcast frame transmission mode and the upgrade process is started (see the broadcast frame transmission logic). Fig. 9 ); Then, if the program type is a fiber board, when the version number of the new program is the same as the version number of the old program, the upgrade is exited (the upgrade is successful by default); when the version number of the new program is different from the version number of the old program, the fiber board starts the program upgrade and lights up the upgrade indicator light. If the upgrade is successful, the version number is saved. If the upgrade fails, the backup old program is started and the upgrade result is sent to the BCMU control board;

[0100] Finally, if the program type is not a fiber board, the new program is broadcast framed to the BMU control board and the upgrade process is started (see the broadcast frame transmission logic). Fig. 9), wait for the program upgrade result, and send the upgrade result to the BMU control board.

[0101] 4. Point-to-point frame transmission mode

[0102] The message format of the point-to-point frame transmission mode upgrade program proposed by the present invention is as follows: Figure 6 As shown, the message sent by the sending side board is defined as follows:

[0103] The maximum length of a message is 214 bytes, of which the frame header occupies 2 bytes (the content is fixed to AA 55), the program level occupies 1 byte (the content 1 represents the first layer, 2 represents the second layer, 3 represents the third layer, and the others are invalid), the program type occupies 1 byte (different boards use different encodings), the version number occupies 2 bytes (indicates the new program version), the frame sequence number occupies 2 bytes (indicates the sequence number of the current message, the first frame message sequence number is 1, and subsequent ones are accumulated), the total number of frames occupies 2 bytes (indicates how many frames of messages are required for the current program to be transmitted), the total length occupies 2 bytes (indicates the current program size, that is, the number of bytes), CRC occupies 2 bytes (indicates the CRC checksum of the upgrade program), and data1~data200 each occupy 1 byte (filled with specific program content, and 0 can be added if less than 200).

[0104] After receiving the upgrade message sent by the sending side board, the target board needs to send a response message to the sending side board so that the sending side board can send the next frame of the upgrade message. If the target board does not send a response message for a long time, the sending side board will resend the upgrade message to ensure that the upgrade program is completely sent and received. The response message sent by the target board is defined as follows:

[0105] The fixed length of the message is 8 bytes, of which the frame header occupies 2 bytes (the content is fixed to AA 55), the program level occupies 1 byte (the same as the message sent by the sending side), the program type occupies 1 byte (the sending side sends the message), the version number occupies 2 bytes (the sending side sends the message), and the frame sequence number occupies 2 bytes (the sending side sends the message. If the version number is the same as the old version number, the target board sets the frame sequence number to 8888, indicating that the program does not need to be upgraded).

[0106] The logic of point-to-point frame transmission upgrade program between boards is shown in Figure 7 , specifically including:

[0107] First, the sending side card calculates the number of frames to be sent according to the length of the upgraded new program, fills and sends the first frame message according to the upgraded frame format (format see Figure 6 );

[0108] Secondly, each time a frame message is sent, it takes a certain amount of time to receive its response message. The sending side card waits for the target card to feed back the response message with a period of time T1 (the time can be set, and its size is proportional to the frame message length). If the frame sequence number of the received response message is 8888, it means that the upgrade version number is the same as the old version number and no upgrade is required. By default, the program upgrade is successful and the result is sent to the sending side card;

[0109] Again, if the frame number of the received response message is not 8888, and this response message is the last frame response message (the frame number is equal to the total number of frames), the program upgrade is successful and the result is sent to the sending side board; then, if the frame number of the received response message is not 8888, and this response message is not the last frame response message, continue to organize the next frame upgrade message and send it to the target board;

[0110] Then, if the sending side board card does not receive the response message from the target board card after the T1 time interval, the sending side board card will resend, and only resend once;

[0111] Finally, if the sending side board card has not received a response message from the target board card after exceeding the T2 time interval (the time can be set, and its size is proportional to T1 and the total number of frames of the upgrade program, and T2 = T1*(total number of frames + 2)), the sending side board card will assume that the program upgrade has failed and send the upgrade result to the sending side board card.

[0112] 5. Broadcast Frame Transmission Mode

[0113] The message format of the patented single-board to multi-board broadcast frame transmission upgrade program is as follows Figure 8 As shown, in order to realize software modular programming, the message format sent by the sending side board card remains consistent with the point-to-point frame transmission message format, which will not be repeated here.

[0114] The sending side board sends the upgrade message at a fixed period. After receiving the upgrade message sent by the sending side board, the target board does not need to send a response message. It only sends a response message when all upgrade messages are received or the version number of the upgrade program is the same as the old version number, thereby improving the efficiency of program upgrade.

[0115] The response message sent by the target board is defined as follows:

[0116] The fixed length of the message is 10 bytes, of which the frame header occupies 2 bytes (the content is fixed to AA 55), the program level occupies 1 byte (the same as the message sent by the sending side), the program type occupies 1 byte (the same as the message sent by the sending side), the version number occupies 2 bytes (the same as the message sent by the sending side), the frame sequence number occupies 2 bytes (the same as the message sent by the sending side, if the version number is the same as the old version number, the target board sets the frame sequence number to 8888, indicating that the program does not need to be upgraded), and the ID number occupies 2 bytes (the unique identity ID of the target board. The sending side board uses this ID to determine which of the multiple target boards of the same type have been upgraded successfully and which have not been upgraded successfully).

[0117] The logic of the inter-board broadcast frame transmission upgrade program is shown in Fig. 9 , specifically including:

[0118] First, the sending side card calculates the number of frames to be sent according to the upgrade program length, and Figure 8 ) fills the message and sends it, and continues to organize and send the next frame of message after the timing is reached until the entire program is sent;

[0119] Secondly, after sending the upgrade message, it is necessary to wait for a certain period of time to receive the response messages from all target boards; the sending side board waits for the target board to feed back the response message with a period of time T1 (the time can be set, and its size is proportional to the size of the program file). If the frame sequence number of the received response message is 8888, it means that the upgrade version number is the same as the old version number and no upgrade is required. The target board ID number is recorded;

[0120] Again, if the frame number of the received response message is not 8888, the upgrade of the target board fails and the ID number is recorded; then, if the received response message is not the response message of the last target board (when the sending side board receives the response messages of all the target boards under its jurisdiction, it is considered that the program upgrade is completed), continue to listen for the response message of the next target board;

[0121] Next, if the sending side board card does not receive all the target board card response messages within the T1 time interval but not exceeding the T2 time interval (the time can be set, and its size is proportional to T1, and T2 = T1*1.5), it will rebroadcast the program file starting from frame 1 and resend it only once;

[0122] Finally, if the sending side board has not received all the target board response messages within the T2 time interval, it will count the target boards that have not received the response messages based on the recorded target board ID numbers and send the upgrade results to the sending side board.

[0123] The distributed energy storage control system and the program online upgrade method provided by the present invention have the following technical advantages:

[0124] First, the program online upgrade method uses only one Ethernet interface to complete the program upgrade of the entire energy storage system, including BMU, BCMU, stack controller, PCS and other functional boards, and can be operated completely remotely, without going to the site, and without any other operations. It is simple and efficient, and the program upgrade method has obvious advantages;

[0125] Secondly, the program online upgrade method adopts two data communication methods: point-to-point frame transmission and broadcast frame transmission, giving full play to their respective advantages. Data transmission is guaranteed by a strict private protocol (frame transmission, packet loss retransmission and strict verification mechanism), and the program upgrade has extremely high reliability and efficiency.

[0126] Thirdly, unlike most energy storage manufacturers, this control system adopts a chassis mode, and the chassis adopts a high-speed LVDS back bus, which provides high-speed communication link support for data sharing between boards in the chassis, which greatly improves the convenience of energy storage system control and protection and the efficiency of program upgrades;

[0127] Finally, this control system adopts a layered design with clear functional divisions among the three control layers. High-speed optical fiber communication is used between the control layers, which has obvious high-speed data transmission capability and extremely high anti-interference ability in harsh energy storage application environments.

[0128] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A distributed energy storage control system, characterized in that: include: A battery stack control layer, a battery cluster control layer, and a battery module control layer connected in sequence by optical fiber communication; The battery stack control layer includes a main control box and a main control board arranged in the main control box, and the main control board is provided with an Ethernet interface, and the Ethernet interface is used for communication connection with a remote control terminal; The battery cluster control layer includes a plurality of cluster control boxes and a BCMU control board arranged in the cluster control box, and the plurality of BCMU control boards are connected to one main control board through optical fiber communication; The battery module control layer includes multiple battery module control systems, each battery module control system includes multiple BMU control boards, and the multiple BMU control boards are electrically connected to the multiple battery modules in a one-to-one correspondence; each battery module control system corresponds to a BCMU control board, and the multiple BMU control boards in each battery module control system are respectively connected to the corresponding BCMU control boards in optical fiber communication.

2. The distributed energy storage control system according to claim 1, characterized in that: The main control chassis and the cluster control chassis are in the form of containers, and the boards in the main control chassis and the cluster control chassis share a high-speed LVDS back bus.

3. The distributed energy storage control system according to claim 1, characterized in that: The control box is also provided with a power board, a PCS board, an IO board, and a sampling board which are electrically connected to the main control board; The cluster control chassis is also provided with a power supply board, an IO board, and a plurality of optical fiber boards electrically connected to the BCMU control board, and the optical fiber board is used for optical fiber communication connection with the BMU control board; The remote control terminal is a web client installed on an operator workstation or an operation and maintenance computer, and a user accesses the Ethernet interface through a web browser of the operator workstation or the operation and maintenance computer.

4. A method for online program upgrade of a distributed energy storage control system, applied to the distributed energy storage control system according to any one of claims 1 to 3, characterized in that: The distributed energy storage control system adopts point-to-point frame transmission mode and broadcast frame transmission mode to forward programs; Point-to-point frame transmission is used for program upgrades between different boards in the chassis. Each frame message sent by the sending board requires a response from the target board, and has a timeout retransmission mechanism. The broadcast frame transmission method is used when there are many target boards with the same program type. The sending board periodically divides the program into frames and sends it. No response from the target board is required in the middle. After sending, it will wait for the upgrade result of the target board. If there are still target boards that have not completed the upgrade within a certain time interval, a broadcast retransmission will be performed.

5. The method for online program upgrade of a distributed energy storage control system according to claim 4, characterized in that: In the program online upgrade method, program forwarding adopts an internal private protocol, and the format of the internal private protocol includes a frame header, program level, program type, program version number, frame sequence number, total number of frames, total program length, and program CRC. When point-to-point frame transmission and broadcast frame transmission are used for program forwarding, frame transmission, packet loss retransmission, and verification mechanisms are provided.

6. The method for online program upgrade of a distributed energy storage control system according to claim 4, characterized in that: The program online upgrade method includes a program upgrade method between a web client and a main control board of a main control box; The program upgrade method between the web client and the main control board of the main control box specifically includes: (1) Enter your username and password in the web client to log in; (2) Enter the upgrade program interface, select the program level and program type to be upgraded. The program level includes three levels, corresponding to the battery stack control layer, battery cluster control layer, and battery module control layer respectively. The program type corresponds to the type code of each board. Enter the version number of the new program, and then load the corresponding file to the web client. (3) The web client calculates the CRC of the new program and sends the new program file along with the program level, program type, program size, version number and CRC value to the main control board of the main control chassis through the HTTP protocol; (4) The program upgrade receiving module of the main control board is responsible for receiving the new program. After receiving the program upgrade instruction, the received new program file is placed in the system temporary path and CRC calculation is performed on the new program file. If the calculated CRC value is the same as the CRC value received by the protocol, the program transmission is considered to be correct. Otherwise, the file transmission is considered to be wrong and the file transmission result is sent to the server. (5) When the program transmission is correct, the program upgrade receiving module of the main control board notifies the program upgrade processing module of the main control board, and the program upgrade processing module performs the program upgrade operation; (6) The program upgrade receiving module of the main control board waits for the upgrade success or failure result sent by the program upgrade processing module, and sends the result to the web client.

7. The method for online program upgrade of a distributed energy storage control system according to claim 4, characterized in that: The program online upgrade method also includes a main control board program upgrade method; the main control board program upgrade method specifically includes: (1) After receiving the program receiving success status sent by the program upgrading receiving module of the main control board, the program upgrading processing module of the main control board determines whether the current energy storage system is in operation. If so, the main control board switches the energy storage system to the upgrading mode. In the upgrading mode, the energy storage system rejects any external charging and discharging instructions; (2) Determine the target control layer and target board based on the program level and program type: When the target control layer is the battery stack control layer, and the target board is the main board, determine whether the version number of the new program is the same as the version number of the old program. If they are not the same, back up the old program, then load the new program into the program area of ​​the main board, start the upgrade, if the upgrade is successful, save the version number of the new program, if the upgrade fails, start the backed up old program, and transmit the upgrade result to the program upgrade receiving module of the main control board; When the target control layer is the battery stack control layer, and the target board is a non-main control board, the main control board forwards the new program to the target board using a point-to-point frame transmission method, and starts the upgrade, waiting for the target board to feedback the upgrade result and sending the upgrade result to the program upgrade receiving module of the main control board; the number of the non-main control boards is unique and there are no boards with the same program type; When the target control layer is not the battery stack control layer, the main control board sends the new program to the BCMU control board using broadcast frame transmission. The BCMU control board starts the BCMU control board program upgrade method, waits for the target board to feedback the upgrade result and sends the upgrade result to the program upgrade receiving module of the main control board.

8. The method for online program upgrade of a distributed energy storage control system according to claim 4, characterized in that: The program online upgrade method also includes a BCMU control board program upgrade method; the BCMU control board program upgrade method specifically includes: (1) After the BCMU control board receives the new program sent by the main control board, it determines the target control layer and target board according to the program level and program type: (2) When the target control layer is the battery cluster control layer and the target board is the BCMU control board, determine whether the version number of the new program is the same as the version number of the old program. If they are not the same, back up the old program, then load the new program into the program area of ​​the BCMU control board, start the upgrade, if the upgrade is successful, save the version number of the new program, if the upgrade fails, start the backed-up old program, and upload the upgrade result to the main control board; (3) When the target control layer is the battery cluster control layer, and the target boards are multiple identical fiber boards, the BCMU control board uses a broadcast frame transmission method to send the new program to multiple identical fiber boards. When the version number of the new program is different from the version number of the old program, the fiber board starts the upgrade. If the upgrade is successful, the version number of the new program is saved. If the upgrade fails, the backup old program is started and the upgrade result is transmitted to the BCMU control board. (4) When the target control layer is the battery cluster control layer, and the target board is neither the BCMU control board nor the fiber board, but is the only other board, the BCMU control board uses point-to-point frame transmission to forward the new program to the target board, starts the upgrade, waits for the target board to feedback the upgrade result, and sends the upgrade result to the BCMU control board; (5) When the target control layer is the battery module control layer, the BCMU control board uses broadcast frame transmission to send the new program to the BMU control board. The BMU control board starts the upgrade and sends the upgrade result to the BCMU control board.

9. The method for online program upgrade of a distributed energy storage control system according to any one of claims 4 to 8, characterized in that: The steps of implementing program upgrade by point-to-point frame transmission are as follows: First, the sending side card calculates the number of frames to be sent according to the length of the upgraded new program, fills and sends the first frame message according to the upgraded frame format; Secondly, the sending side card waits for the target card to feed back a response message with a period of time T1. If the frame number of the received response message is 8888, it means that the new program version number is the same as the old program version number and no upgrade is required. By default, the program upgrade is successful and the result is sent to the sending side card; Again, if the frame number of the received response message is not 8888, and this response message is the last frame response message, the program upgrade is successful and the result is sent to the sending side board; then, if the frame number of the received response message is not 8888, and this response message is not the last frame response message, continue to organize the next frame upgrade message and send it to the target board; Then, if the sending side board card does not receive the response message from the target board card after exceeding the T1 time interval, the sending side board card will resend; Finally, if the sending side board still does not receive a response message from the target board after the T2 time interval, the sending side board defaults to program upgrade failure and sends the upgrade result to the sending side board, where T2>T1.

10. The method for online program upgrade of a distributed energy storage control system according to any one of claims 4 to 8, characterized in that: The steps of program forwarding in the broadcast frame transmission mode to implement program upgrade are as follows: First, the sending side card calculates the number of frames to be sent according to the length of the new program to be upgraded, fills the message according to the upgraded frame format and sends it, and continues to organize and send the next frame message after the timing is reached until the entire new program is sent; Secondly, the sending side card waits for the target card to send a response message with a period of time T1. If the frame number of the received response message is 8888, it means that the new program version number is the same as the old program version number and no upgrade is required. The target card ID number is recorded. Again, if the frame number of the received response message is not 8888, the upgrade of the target board fails and the ID number is recorded; then, if the received response message is not the response message of the last target board, continue to listen to the response message of the next target board; Then, if the sending side board card does not receive all the target board card response messages within the T1 time interval but not exceeding the T2 time interval, it will rebroadcast the new program file starting from frame 1; where T2>T1; Finally, if the sending side board has not received all the target board response messages within the T2 time interval, it will count the target boards that have not received the response messages based on the recorded target board ID numbers and send the upgrade results to the sending side board.

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