Energy storage module, energy storage system, charging method and storage medium

Abstract

The invention provides an energy storage module, an energy storage system, a charging method and a storage medium. The energy storage module comprises an electrochemical device; and the power supply module is connected with the electrochemical device and is used for charging the electrochemical device when the energy storage module is in the bypass and the SOC of the electrochemical device is lower than a preset threshold value. According to the energy storage module, the electrochemical device in the bypass energy storage module with the over-discharge risk is charged, so that the probability of frequent shutdown of the energy storage system caused by over-discharge of the electrochemical device in the bypass energy storage module is reduced, and the utilization rate of the energy storage system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage systems, and in particular to an energy storage module, an energy storage system, a charging method and a storage medium. Background Art

[0002] With the rapid development of new energy technologies, energy storage systems have become one of the more important research directions in the field of new energy. Due to the intermittent and fluctuating characteristics of new energy generation such as photovoltaic power generation and wind power generation, the power grid is equipped with energy storage systems on the power generation side, transmission side, and power consumption side to perform peak and frequency regulation and inertia support on the power grid.

[0003] The energy storage system is composed of multiple energy storage modules, and redundant bypass technology is used to improve the reliability and operating efficiency of the energy storage system. When a certain energy storage module in the energy storage system fails, the failed energy storage module is bypassed so that other energy storage modules can continue to work. After the energy storage module is bypassed, the battery in the energy storage module will self-discharge. The bypassed energy storage module can only rely on the remaining power of the battery itself to supply the self-discharge power. If the battery power in the bypassed energy storage module is low, there is a risk of over-discharge, and the energy storage system needs to be shut down for maintenance, which greatly reduces the utilization rate of the energy storage system. Summary of the invention

[0004] The purpose of the embodiments of the present application is to provide an energy storage module, an energy storage system, a charging method and a storage medium to charge an electrochemical device in a bypass energy storage module that has an over-discharge risk, thereby reducing the probability of frequent shutdown of the energy storage system due to over-discharge of the electrochemical device in the bypass energy storage module, thereby improving the utilization rate of the energy storage system.

[0005] In a first aspect, an embodiment of the present application provides an energy storage module, comprising: an electrochemical device; a power supply module connected to the electrochemical device; and a control module connected to the power supply module, for controlling the power supply module to charge the electrochemical device when the energy storage module is in bypass and the SOC of the electrochemical device is lower than a preset threshold.

[0006] In the embodiment of the present application, a power supply module is provided in the energy storage module. When the energy storage module is in bypass and the SOC of the electrochemical device in the energy storage module is low (there is a risk of over-discharge), the power supply module charges the electrochemical device so that the electrochemical device has sufficient power to maintain self-discharge, thereby reducing the probability of over-discharge of the electrochemical device and reducing the frequency of shutdown and maintenance of the energy storage system, thereby improving the utilization and reliability of the energy storage system.

[0007] In an optional embodiment, the power supply module includes: a power extraction unit and a power supply unit; the power extraction unit is respectively connected to the electrochemical device, the power supply unit and the control module, and the control module is used to control the power extraction unit to be turned on when the energy storage module is in bypass and the SOC of the electrochemical device is lower than a preset threshold, so that the power supply unit charges the electrochemical device.

[0008] In the embodiment of the present application, considering the difference in voltage and power between the power supply unit and the electrochemical device, a power extraction unit is provided to achieve power and voltage matching between the power supply unit and the electrochemical device, so that the power supply unit can safely charge the electrochemical device.

[0009] In an optional implementation, the power supply unit includes: a power supply network or an energy storage power supply.

[0010] In a second aspect, an embodiment of the present application provides a charging method, comprising: in response to an energy storage module being in bypass, obtaining the SOC of an electrochemical device in the energy storage module; in response to the SOC of the electrochemical device being less than a first threshold, controlling a power supply module to charge the electrochemical device.

[0011] In the embodiment of the present application, when it is determined that the energy storage module is in bypass and the SOC of the electrochemical device in the energy storage module is less than a first threshold value, it is determined that the electrochemical device is at risk of over-discharge, so the power supply module is controlled to charge the electrochemical device so that the electrochemical device has sufficient power to maintain self-discharge, thereby reducing the probability of over-discharge of the electrochemical device and reducing the frequency of shutdown and maintenance of the energy storage system, thereby improving the utilization and reliability of the energy storage system.

[0012] In an optional embodiment, after controlling the power supply module in the energy storage module to charge the electrochemical device, the method further includes: in response to the SOC of the electrochemical device being greater than a second threshold, controlling the power supply module to stop charging the electrochemical device.

[0013] In the embodiment of the present application, from the perspective of energy saving, since the energy storage module is already in bypass state, it will no longer provide energy storage function for the power grid, and the energy storage module only needs to maintain self-discharge. Therefore, after the SOC of the electrochemical device is greater than the second threshold, charging is stopped to reduce power loss.

[0014] In an optional embodiment, after obtaining the SOC of the electrochemical device in the energy storage module in response to the energy storage module being in bypass, the method further includes: in response to the SOC of the electrochemical device being less than a first threshold, marking the electrochemical device as an over-discharge risk electrochemical device.

[0015] In the embodiment of the present application, when the SOC of the electrochemical device is less than the first threshold, the electrochemical device is marked as an over-discharge risk electrochemical device, so that the electrochemical device can be managed according to the over-discharge risk mark later.

[0016] In an optional embodiment, the method further includes: in response to the SOC of the electrochemical device being greater than a second threshold and the electrochemical device being marked as the over-discharge risk electrochemical device, controlling the power supply module to stop charging the electrochemical device and clearing the over-discharge risk electrochemical device mark of the electrochemical device.

[0017] In the embodiment of the present application, when the SOC of the electrochemical device is greater than the second threshold, charging of the electrochemical device is stopped and an over-discharge risk electrochemical device flag of the electrochemical device is cleared to reduce power loss.

[0018] In a third aspect, an embodiment of the present application provides an energy storage system, comprising: a plurality of energy storage modules as described in any one of the aforementioned embodiments; and a battery management system for executing a charging method as described in any one of the aforementioned embodiments.

[0019] In a fourth aspect, an embodiment of the present application provides an energy storage system, comprising: a first energy storage module, a second energy storage module and a power extraction module; the power extraction module is respectively connected to a first electrochemical device of the first energy storage module and a second electrochemical device of the second energy storage module; when the first energy storage module is in bypass and the SOC of the first electrochemical device is lower than a preset threshold, the second electrochemical device is configured to charge the first electrochemical device through the power extraction module.

[0020] In the embodiment of the present application, the electrochemical devices in two energy storage modules in the energy storage system are connected through a power extraction unit. When a bypass occurs in one energy storage module and its corresponding electrochemical device is at risk of over-discharge, the electrochemical device in the energy storage module connected to the energy storage module charges the electrochemical device of the energy storage module. There is no need to set up other power supply devices. The energy storage module at risk of over-discharge is charged by other energy storage modules in the energy storage system.

[0021] In an optional embodiment, the power extraction module includes a first power extraction unit and a second power extraction unit, the first power extraction unit is arranged in the first energy storage module and connected to the first electrochemical device; the second power extraction unit is arranged in the second energy storage module and connected to the second electrochemical device; the first power extraction unit is connected to the second power extraction unit; when the first energy storage module is in bypass and the SOC of the first electrochemical device is lower than a preset threshold, the second electrochemical device is configured to charge the first chemical device through the first power extraction unit and the second power extraction unit.

[0022] In an optional embodiment, the energy storage system further includes a battery management system for executing the charging method as described in any one of the aforementioned embodiments, and the power supply module is the second electrochemical device.

[0023] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer program instructions are stored. When the computer program instructions are read and executed by a computer, a charging method as described in any one of the aforementioned embodiments is executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0025] Figure 1 A schematic diagram of the structure of an energy storage module provided in an embodiment of the present application;

[0026] Figure 2 A schematic diagram of the structure of another energy storage module provided in an embodiment of the present application;

[0027] Figure 3 A schematic diagram of the structure of a half-bridge energy storage module provided in an embodiment of the present application;

[0028] Figure 4 A schematic diagram of the structure of a full-bridge energy storage module provided in an embodiment of the present application;

[0029] Figure 5 A flowchart of a charging method provided in an embodiment of the present application;

[0030] Figure 6 A diagram of an implementation process of a charging method provided in an embodiment of the present application;

[0031] Figure 7 A topological diagram of an energy storage system provided in an embodiment of the present application;

[0032] Figure 8 A topological diagram of another energy storage system provided in an embodiment of the present application;

[0033] Fig. 9 A topological diagram of another energy storage system provided in an embodiment of the present application;

[0034] Fig.10 A structural block diagram of an energy storage system provided in an embodiment of the present application;

[0035] Fig.11 A structural block diagram of another energy storage system provided in an embodiment of the present application.

[0036] Icon: 100-energy storage module; 110-electrochemical device; 120-power supply module; 1201-power extraction unit; 1202-power supply unit; 130-control module; 1000-energy storage system; 1010-first energy storage module; 1020-second energy storage module; 1011-first electrochemical device; 1021-second electrochemical device; 1030-power extraction module; 1031-first power extraction unit; 1032-second power extraction unit. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0038] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it is not necessary to further define and explain it in the subsequent drawings. At the same time, in the description of this application, relational terms such as "first", "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements that are not clearly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements limited by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements.

[0039] Furthermore, the term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The term "plurality" refers to more than two (including two).

[0040] With the rapid development of new energy technologies, energy storage systems have become one of the more important research directions in the field of new energy. Due to the intermittent and fluctuating characteristics of new energy generation such as photovoltaic power generation and wind power generation, the power grid is equipped with energy storage systems on the power generation side, transmission side, and power consumption side to perform peak and frequency regulation and inertia support on the power grid.

[0041] Cascade high-voltage energy storage systems have the advantages of large capacity, low cost, high efficiency, high safety, and rapid response, and are widely used. Redundant bypass technology is used to improve the reliability and operating efficiency of energy storage systems. When a storage module in the energy storage system fails, the failed storage module is bypassed so that other storage modules can continue to work.

[0042] After the energy storage module is bypassed, the batteries in the energy storage module will self-discharge. The bypassed energy storage module can only rely on the remaining power of its own electrochemical device to supply the self-discharge power. If the electrochemical device of the bypassed energy storage module has a low power level, there is a risk of over-discharge. Over-discharge of the electrochemical device will cause the performance of the electrochemical device to deteriorate, reduce the capacity of the electrochemical device, and thus reduce the service life of the energy storage module. Therefore, when the energy storage module in the energy storage system is at risk of over-discharge, the energy storage system will be shut down for maintenance, reducing the utilization rate of the energy storage system.

[0043] In order to solve the problem that the energy storage system is frequently shut down due to over-discharge of the bypass energy storage module, thereby resulting in low utilization of the energy storage system, the embodiment of the present application provides a power supply module in each energy storage module in the energy storage system, and charges the electrochemical device when the energy storage module is in bypass and the SOC (State Of Charge) of the electrochemical device in the energy storage module is low, so that the electrochemical device has sufficient electricity for self-discharge, reduces the probability of over-discharge of the electrochemical device, reduces the frequency of shutdown of the energy storage system for maintenance, and thus improves the utilization and reliability of the energy storage system.

[0044] The energy storage system provided in the embodiments of the present application includes, but is not limited to: energy storage power supply systems such as hydropower, thermal power, wind power and solar power stations; energy storage systems for electric vehicles such as electric bicycles, electric motorcycles, and electric cars; and energy storage systems in multiple fields such as military equipment and aerospace.

[0045] See also Figure 1 , Figure 1 The energy storage module 100 includes an electrochemical device 110 , a power supply module 120 and a control module 130 .

[0046] The electrochemical device 110 is a device that converts chemical energy into electrical energy to achieve an electrochemical reaction. The electrochemical device 110 includes but is not limited to a lithium battery, a sodium battery, a nickel-hydrogen battery, and a lead-acid battery.

[0047] The power supply module 120 is connected to the electrochemical device 110, and the control module 130 is connected to the power supply module 120. If the energy storage module 100 is in bypass and the SOC of the electrochemical device 110 is lower than a preset threshold, it means that there is an over-discharge risk in the electrochemical device 110 in the energy storage module 100, and the control module 130 controls the power supply module 120 to charge the electrochemical device 110.

[0048] In some embodiments, the control module 130 may be a main control card on the energy storage module 100. The main control card may detect in real time whether the energy storage module 100 is in a bypass state. The main control card may also obtain the SOC of the electrochemical device 110 in the energy storage module 100. When the main control card determines that the energy storage module 100 is in bypass and the SOC of the electrochemical device 110 is lower than a preset threshold, the power supply module 120 is controlled to charge the electrochemical device 110. The preset threshold may be determined according to the discharge safety lower limit value corresponding to the battery type of the electrochemical device 110. The discharge safety lower limit value is usually expressed by the SOC of the battery, that is, when the SOC of the battery is lower than the discharge safety lower limit value, it indicates that the battery is at risk of over-discharge.

[0049] In some embodiments, different types of batteries have different discharge safety limits, and the preset threshold can be set to the discharge safety limit of the battery. For example, if the electrochemical device 110 uses a type A battery, the discharge safety limit of the type A battery is 15%, then the preset threshold is set to 15%; if the electrochemical device 110 uses a type B battery, the discharge safety limit of the type B battery is 20%, then the preset threshold is set to 20%.

[0050] In other embodiments, a certain margin may be considered when setting the preset threshold, and the preset threshold may be set to be slightly larger than the discharge safety lower limit of the battery. For example, if the electrochemical device 110 uses a type A battery, the discharge safety lower limit of the type A battery is 15%, then the preset threshold is set to 20%; if the electrochemical device 110 uses a type B battery, the discharge safety lower limit of the type B battery is 20%, then the preset threshold is set to 25%.

[0051] As an optional implementation, Figure 2As shown, the power supply module 120 includes a power extraction unit 1201 and a power supply unit 1202. The power extraction unit 1201 is arranged between the electrochemical device 110 and the power supply unit 1202, and the control module 130 is connected to the power extraction unit 1201. The power supply unit 1202 is used to provide electrical energy. When there is a risk of over-discharge in the electrochemical device 110, the control block controls the power extraction unit 1201 to be turned on, so that the power supply unit 1202 is connected to the electrochemical device 110, and the power supply unit 1202 charges the electrochemical device 110.

[0052] According to the difference of actual application scenarios, the power taking unit 1201 has multiple implementation modes.

[0053] For example, if the power and voltage of the power supply unit 1202 are the same as the power and voltage of the electrochemical device 110, the power extraction unit 1201 may be a DC circuit breaker. The DC circuit breaker acts as a switch. When the electrochemical device 110 needs to be charged, the DC circuit breaker is turned on, the power supply unit 1202 is connected to the electrochemical device 110, and the power supply unit 1202 charges the electrochemical device 110; when the electrochemical device 110 does not need to be charged, the DC circuit breaker is turned off, the power supply unit 1202 is disconnected from the electrochemical device 110, and the power supply unit 1202 no longer charges the electrochemical device 110.

[0054] For another example, if the power and voltage of the power supply unit 1202 differ from the power and voltage of the electrochemical device 110, the power extraction unit 1201 may be a device with voltage and power adjustment functions, such as power electronic devices, DC-DC (Direct Current-Direct Current) converters, etc. When the electrochemical device 110 needs to be charged, the power extraction unit 1201 matches the power and voltage, so that the power supply unit 1202 can charge the electrochemical device 110 normally. For example, the charging voltage provided by the power supply unit 1202 is 220V, and the rated charging voltage of the electrochemical device 110 is 15V. When the electrochemical device 110 needs to be charged, the power extraction unit 1201 converts the 220V charging voltage provided by the power supply unit 1202 into 15V, and then connects the power supply unit 1202 to the electrochemical device 110, so that the power supply unit 1202 charges the electrochemical device 110.

[0055] As an optional embodiment, the power supply unit 1202 may be a power supply network. In this embodiment, the power grid where the energy storage system where the energy storage module 100 is located provides power to the electrochemical device 110. The power supply network may be a DC bus, a station power supply, etc. in the power grid where the energy storage system where the energy storage module 100 is located is located.

[0056] As another optional implementation, the power supply unit 1202 may be an energy storage power supply. In this implementation, an energy storage power supply is provided to provide electrical energy to the electrochemical device 110. The energy storage power supply may be various energy storage devices, batteries, DC power supplies, and the like.

[0057] The embodiment of the present application does not limit the specific form of the power supply unit 1202 , and any device that can provide electrical energy to the electrochemical device 110 can be used as the power supply unit 1202 .

[0058] For further information, see Figure 3 and Figure 4 , Figure 3 A schematic diagram of the structure of a half-bridge energy storage module provided in an embodiment of the present application is shown in FIG. Figure 4 A schematic diagram of the structure of a full-bridge energy storage module provided in an embodiment of the present application. In the embodiment of the present application, the energy storage module 100 can be set as a half-bridge power module or a full-bridge power module. When the energy storage module 100 is fault-free, the confluence switch is closed, the electrochemical device 110 forms a loop with the discharge resistor R, the capacitor C, the transistor S1, the transistor S2, the transistor S3 and the transistor S4, and the energy storage module 100 works normally; when the energy storage module 100 fails, the energy storage module 100 is bypassed, the confluence switch is disconnected, the electrochemical device 110 is disconnected from the discharge resistor R, the capacitor C, the transistor S1, the transistor S2, the transistor S3 and the transistor S4, and stops working.

[0059] The present application also provides a charging method. Figure 5 The implementation process is described.

[0060] S1: In response to the energy storage module being in bypass mode, obtaining the SOC of the electrochemical device in the energy storage module.

[0061] In the embodiment of the present application, each energy storage module may be configured with a main control card, which monitors whether it is in a bypass state. When it is determined that the energy storage module is in a bypass state, the main control card sends the bypass state information to the battery management system (BMS). After the BMS determines that the energy storage module is in a bypass state, it obtains the SOC of the electrochemical device corresponding to the energy storage module.

[0062] S2: In response to the SOC of the electrochemical device being less than a first threshold, controlling the power supply module to charge the electrochemical device.

[0063] In the embodiment of the present application, if the SOC of the electrochemical device is less than the first threshold, the BMS controls the power supply module to charge the electrochemical device. The first threshold is the same as the preset threshold in the aforementioned energy storage module. To keep the specification concise, it is not repeated here. The way in which the power supply module charges the electrochemical device is the same as the working mode of the power supply module in the aforementioned energy storage module. To keep the specification concise, it is not repeated here.

[0064] Further, as an optional implementation, after step S2, the charging method provided in the embodiment of the present application further includes: in response to the SOC of the electrochemical device being greater than a second threshold, controlling the power supply module to stop charging the electrochemical device.

[0065] In the embodiment of the present application, after the BMS controls the power supply module to charge the electrochemical device, the SOC of the electrochemical device is continuously monitored. When the SOC of the electrochemical device is greater than the second threshold, it means that there is a certain amount of electricity in the electrochemical device for self-discharge. From the perspective of energy saving, since the energy storage module is already in a bypass state and will no longer provide energy storage function to the power grid, the energy storage module only needs to maintain self-discharge. Therefore, after the SOC of the electrochemical device is greater than the second threshold, charging can be stopped. After charging is stopped, under the action of self-discharge, the SOC of the energy storage module continues to decrease. When the SOC of the energy storage module is lower than the first threshold again, the BMS controls the power supply module to charge the electrochemical device in the energy storage module again.

[0066] The second threshold is greater than the first threshold, and the specific value of the second threshold can be set according to actual conditions. For example, the second threshold can be set to 60%, 65%, 70%, etc. This application does not make specific limitations on this.

[0067] Further, as an optional implementation, after step S1, the charging method provided in the embodiment of the present application further includes: in response to the SOC of the electrochemical device being less than a first threshold, marking the electrochemical device as an over-discharge risk electrochemical device.

[0068] In the embodiment of the present application, in order to facilitate the management of the electrochemical device by the BMS, the BMS marks the electrochemical device as an over-discharge risk electrochemical device when it determines that the energy storage module is in bypass and the SOC of the electrochemical device in the energy storage module is less than the first threshold. Then the BMS executes the above step S2 to charge the electrochemical device marked as over-discharge risk. When the BMS subsequently monitors the electrochemical device, if the electrochemical device is marked as an over-discharge risk electrochemical device, it means that the electrochemical device is being charged; conversely, if the electrochemical device is not marked as an over-discharge risk electrochemical device, it means that the electrochemical device is not being charged.

[0069] Further, as an optional implementation, the charging method provided in the embodiment of the present application also includes: in response to the SOC of the electrochemical device being greater than a second threshold and the electrochemical device being marked as an over-discharge risk electrochemical device, controlling the power supply module to stop charging the electrochemical device and clearing the over-discharge risk electrochemical device mark of the electrochemical device.

[0070] In the embodiment of the present application, during the process of BMS monitoring the SOC of the electrochemical device, after determining that an electrochemical device is marked as an over-discharge risk electrochemical device, it is determined whether the SOC of the electrochemical device is greater than a second threshold value. If the SOC of the electrochemical device is greater than the second threshold value, it indicates that the electrochemical device has sufficient power for self-discharge, and the power supply module is controlled to stop charging the electrochemical device and clear the over-discharge risk electrochemical device mark of the electrochemical device; if the SOC of the electrochemical device is less than the second threshold value, it indicates that the electrochemical device still needs to continue charging, and the electrochemical device does not need to be processed.

[0071] The following is an introduction to the charging method according to an embodiment of the present application with reference to a specific example.

[0072] like Figure 6 As shown, first collect the working status of the energy storage module to determine whether the energy storage module is bypassed. If the energy storage module is not bypassed, no processing is required. If the energy storage module is bypassed, determine whether the electrochemical device in the energy storage module is marked as an over-discharge risk electrochemical device.

[0073] If the electrochemical device is not marked as an over-discharge risk electrochemical device, it is determined whether the SOC of the electrochemical device is less than the first threshold value. If the SOC of the electrochemical device is less than the first threshold value, it indicates that the electrochemical device has an over-discharge risk, so the electrochemical device is marked as an over-discharge risk electrochemical device and the electrochemical device is charged. If the SOC of the electrochemical device is greater than the first threshold value, it indicates that the electrochemical device does not have an over-discharge risk and no processing is required.

[0074] If the electrochemical device is marked as an over-discharge risk electrochemical device, determine whether the SOC of the electrochemical device is greater than the second threshold. If the SOC of the electrochemical device is greater than the second threshold, it means that the electrochemical device has completed charging, and charging of the electrochemical device is stopped and the over-discharge risk electrochemical device mark of the electrochemical device is cleared. If the SOC of the electrochemical device is less than the second threshold, it means that the electrochemical device still needs to be charged and no processing is required.

[0075] In some embodiments, a battery management system is provided in the energy storage system as an execution body of the above charging method to perform charging management on each energy storage module in the energy storage system.

[0076] In other embodiments, a battery management system is provided on each energy storage module as an executor of the above-mentioned charging method, and the battery management system on each energy storage module performs charging management on the energy storage module.

[0077] In other embodiments, the charging method is performed by the control module 130 in each energy storage module 100 , and the control module 130 performs charging management on the energy storage module 100 .

[0078] Furthermore, an embodiment of the present application provides an energy storage system, which includes multiple energy storage modules 100 in the above embodiments. According to the difference in actual application scenarios, the energy storage system can output AC power or DC power. The energy storage system has multiple topological forms.

[0079] In the application scenario where the energy storage system outputs AC power, as an optional implementation method, please refer to Figure 7 , Figure 7 A topological diagram of an energy storage system provided in an embodiment of the present application. In the embodiment of the present application, the energy storage system includes a three-phase circuit, each phase circuit includes a bridge arm, and a bridge arm includes a plurality of cascaded energy storage modules 100 and an inductor, and the three-phase circuit is respectively connected to the A phase, B phase and C phase of the AC side. Each energy storage module 100 is connected in parallel with a bypass switch (not shown in the figure). When an energy storage module 100 fails, the bypass switch corresponding to the energy storage module 100 is closed, and the energy storage module 100 is bypassed, and other energy storage modules 100 continue to work normally.

[0080] The energy storage system can be set up in the power grid, and the energy storage module 100 is used to store the electric energy in the power grid, or to release the electric energy to the power grid. During the off-peak period of electricity consumption, the power grid has excess electric energy, and the electrochemical device 110 in the energy storage module 100 is charged, thereby converting part of the power grid electric energy into the electric energy in the energy storage module 100; conversely, during the peak period of electricity consumption or other reasons that cause the power grid to be low, the electrochemical device 110 in the energy storage module 100 is discharged, and the electric energy in the energy storage module 100 is converted into the power grid electric energy, thereby compensating for the power grid electric energy.

[0081] As another alternative implementation, see Figure 8 , Figure 8A topological diagram of another energy storage system provided for an embodiment of the present application. In the embodiment of the present application, the energy storage system includes a three-phase circuit, each phase circuit includes an upper bridge arm and a lower bridge arm, the upper bridge arm and the lower bridge arm are formed by a plurality of energy storage modules 100 and an inductor cascade, and the three-phase circuit is respectively connected to the A phase, the B phase and the C phase of the AC side. Connected to the AC side. Each energy storage module 100 is connected in parallel with a bypass switch (not shown in the figure). When an energy storage module 100 fails, the bypass switch corresponding to the energy storage module 100 is closed, and the energy storage module 100 is bypassed, and the other energy storage modules 100 continue to work normally. The working mode of the energy storage system in the embodiment of the present application is the same as the working mode of the energy storage system in the aforementioned embodiment. In order to make the specification concise, it will not be repeated here.

[0082] In the application scenario where the energy storage system outputs DC power, please refer to Fig. 9 , Fig. 9 A topological diagram of another energy storage system provided in an embodiment of the present application. In the embodiment of the present application, the energy storage system includes a bridge arm, which includes a plurality of cascaded energy storage modules 100 and two inductors, and the bridge arm is arranged between the positive and negative poles of the DC bus. Each energy storage module 100 is connected in parallel with a bypass switch (not shown in the figure). When an energy storage module 100 fails, the bypass switch corresponding to the energy storage module 100 is closed to bypass the energy storage module 100, and the other energy storage modules 100 continue to work normally. The working mode of the energy storage system in the embodiment of the present application is the same as the working mode of the energy storage system in the aforementioned embodiment. In order to make the specification concise, it will not be repeated here.

[0083] In some embodiments, the energy storage system in the embodiment of the present application further includes a BMS, which is used to execute the aforementioned charging method and perform charging management on each energy storage module in the energy storage system.

[0084] In other embodiments, each energy storage module in the energy storage system in the embodiment of the present application is provided with a BMS, and the BMS is used to execute the aforementioned charging method, and the BMS in each energy storage module performs charging management on the energy storage module.

[0085] The present application also provides an energy storage system. Fig.10 , Fig.10A structural block diagram of an energy storage system provided in an embodiment of the present application. The energy storage system 1000 includes a first energy storage module 1010, a second energy storage module 1020 and a power extraction module 1030. The power extraction module 1030 is respectively connected to the first electrochemical device 1011 of the first energy storage module 1010 and the second electrochemical device 1021 of the second energy storage module 1020; when the first energy storage module 1010 is in bypass and the SOC of the first electrochemical device 1011 is lower than a preset threshold, the second electrochemical device 1021 is configured to charge the first electrochemical device 1011 through the power extraction module 1030.

[0086] In the embodiment of the present application, the energy storage system is composed of a plurality of energy storage modules, and the electrochemical devices in every two energy storage modules in the energy storage system are connected by a power extraction device. The first energy storage module 1010 and the second energy storage module 1020 are two energy storage modules with the same functions. For ease of understanding, the energy storage module with the risk of over-discharge is referred to as the first energy storage module 1010, and the energy storage module with normal operation is referred to as the second energy storage module 1020.

[0087] After the SOC of the first electrochemical device 1011 in the first energy storage module 1010 is less than a preset threshold, the second electrochemical device 1021 in the second energy storage module 1020 charges the first electrochemical device 1011 through the power extraction module 1030 so that the first electrochemical device 1011 has enough power to maintain self-discharge.

[0088] In some embodiments, the power extraction module 1030 may be disposed in the first energy storage module 1010. In other embodiments, the power extraction module 1030 may be disposed in the second energy storage module 1020. In other embodiments, the power extraction module 1030 may be disposed separately, and disposed between the first energy storage module 1010 and the second energy storage module 1020. The embodiment of the present application does not specifically limit the position of the power extraction module 1030.

[0089] As an alternative implementation, see Fig.11 , Fig.11 A structural block diagram of another energy storage system provided for an embodiment of the present application. The power extraction module 1030 includes a first power extraction unit 1031 and a second power extraction unit 1032, wherein the first power extraction unit 1031 is disposed in the first energy storage module 1010 and connected to the first electrochemical device 1011. The second power extraction unit 1032 is disposed in the second energy storage module 1020 and connected to the second electrochemical device 1021. The first power extraction unit 1031 is connected to the second power extraction unit 1032. When the first energy storage module 1010 is in bypass and the SOC of the first electrochemical device 1011 is lower than a preset threshold, the second electrochemical device 1021 is configured to charge the first electrochemical device 1011 through the first power extraction unit 1031 and the second power extraction unit 1032.

[0090] In the embodiment of the present application, the working mode of the first power extraction unit 1031 and the second power extraction unit 1032 can refer to the working mode of the power extraction unit 1201 in the aforementioned energy storage module 100, and will not be repeated here to make the description concise.

[0091] In the present application example, multiple energy storage modules in the energy storage system can be composed according to the needs of the actual application scenario. Figure 7-9 The energy storage system shown in the figure outputs DC or AC power. Each energy storage module can be set as follows according to the requirements of the actual application scenario: Figure 3-4 The half-bridge power module or full-bridge power module shown.

[0092] In some embodiments, the energy storage system in the embodiment of the present application further includes a BMS, which is used to execute the aforementioned charging method and perform charging management on each energy storage module in the energy storage system.

[0093] In other embodiments, each energy storage module in the energy storage system in the embodiment of the present application is provided with a BMS, and the BMS is used to execute the aforementioned charging method, and the BMS in each energy storage module performs charging management on the energy storage module.

[0094] In addition, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a computer, the steps of the charging method in the above embodiment are executed.

[0095] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0096] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0097] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0098] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a computer-readable storage medium, including several instructions for enabling a computer device (which can be a personal computer, a laptop, a server, or an electronic device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned computer-readable storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0099] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An energy storage module, characterized in that: include: Electrochemical devices; A power supply module connected to the electrochemical device; The control module is connected to the power supply module, and controls the power supply module to charge the electrochemical device when the energy storage module is in bypass and the SOC of the electrochemical device is lower than a preset threshold.

2. The energy storage module according to claim 1, characterized in that: The power supply module includes: a power extraction unit and a power supply unit; the power extraction unit is respectively connected to the electrochemical device, the power supply unit and the control module, and the control module controls the power extraction unit to be turned on when the energy storage module is in bypass and the SOC of the electrochemical device is lower than a preset threshold, so that the power supply unit charges the electrochemical device.

3. The energy storage module according to claim 2, characterized in that: The power supply unit includes: a power supply network or an energy storage power supply.

4. A charging method, characterized in that: include: In response to the energy storage module being in bypass, obtaining the SOC of the electrochemical device in the energy storage module; In response to the SOC of the electrochemical device being less than a first threshold, the power supply module is controlled to charge the electrochemical device.

5. The charging method according to claim 4, characterized in that: After controlling the power supply module in the energy storage module to charge the electrochemical device, the method further includes: In response to the SOC of the electrochemical device being greater than a second threshold, the power supply module is controlled to stop charging the electrochemical device.

6. The charging method according to claim 4, characterized in that: After obtaining the SOC of the electrochemical device in the energy storage module in response to the energy storage module being in bypass, the method further includes: In response to the SOC of the electrochemical device being less than a first threshold, the electrochemical device is marked as an over-discharge risk electrochemical device.

7. The charging method according to claim 6, characterized in that: The method further comprises: In response to the SOC of the electrochemical device being greater than a second threshold and the electrochemical device being marked as the over-discharge risk electrochemical device, the power supply module is controlled to stop charging the electrochemical device and clear the over-discharge risk electrochemical device mark of the electrochemical device.

8. An energy storage system, characterized in that: include: A plurality of energy storage modules according to any one of claims 1 to 3; A battery management system, configured to execute the method as claimed in any one of claims 4 to 7.

9. An energy storage system, characterized in that: include: A first energy storage module, a second energy storage module and a power extraction module; the power extraction module is respectively connected to a first electrochemical device of the first energy storage module and a second electrochemical device of the second energy storage module; When the first energy storage module is in bypass mode and the SOC of the first electrochemical device is lower than a preset threshold, the second electrochemical device is configured to charge the first electrochemical device through the power extraction module.

10. The energy storage system according to claim 9, characterized in that: The power extraction module includes a first power extraction unit and a second power extraction unit, the first power extraction unit is arranged in the first energy storage module and connected to the first electrochemical device; the second power extraction unit is arranged in the second energy storage module and connected to the second electrochemical device; the first power extraction unit is connected to the second power extraction unit; when the first energy storage module is in bypass and the SOC of the first electrochemical device is lower than a preset threshold, the second electrochemical device is configured to charge the first electrochemical device through the first power extraction unit and the second power extraction unit.

11. The energy storage system according to claim 9 or 10, characterized in that: The energy storage system further includes a battery management system for executing the method according to any one of claims 4 to 7, and the power supply module is the second electrochemical device.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer program instructions, and when the computer program instructions are read and executed by a computer, the method according to any one of claims 4 to 7 is executed.

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