Energy storage system and control method and device thereof

Abstract

The invention provides an energy storage system and a control method and device thereof, and the control method of the energy storage system comprises the steps: obtaining a battery normalization scoring parameter of a second sub-module under the condition that the second sub-module is used for the energy storage system comprising a plurality of first sub-modules, and controlling the second sub-module to maintain an input state or cut off the second sub-module in combination with a preset score limit value. The control of the second sub-module is realized on the basis of fully considering the battery capacity of the second sub-module, so that the coordination control of different sub-modules is realized, the performance of the novel sub-module can be fully tested, and the stable response of the whole system is facilitated.

Description

Technical Field

[0001] The present application relates to the field of energy storage technology, and more specifically, to an energy storage system and a control method and device thereof. Background Art

[0002] Energy storage technology is widely used because it can improve the utilization rate of renewable energy power generation, smooth active power fluctuations, and play a role in peak load reduction and valley filling in power systems. Among them, the direct-mounted energy storage power conversion system has the advantages of modular structure and high safety, and has received widespread attention in high-voltage and large-capacity occasions. The quality of its control strategy directly affects the performance and reliability of the energy storage system.

[0003] In actual projects, before the energy storage valve composed of new sub-modules is put into use, a single new sub-module will be added to the existing energy storage valve for performance testing. At this time, the energy storage system is composed of different types of sub-modules. The current control method mainly adopts the original control strategy for the existing sub-modules to control the new sub-module. However, the new sub-module and the existing sub-module often have differences in capacity, voltage level, etc. Therefore, this control method cannot fully test the performance of the new sub-module, and is also not conducive to the overall stable response of the system. Summary of the invention

[0004] In view of the above problems, the present application provides an energy storage system and a control method and device thereof to solve the problem that the control method in the related art cannot fully test the performance of the new sub-module, and is also not conducive to the stable response of the entire system.

[0005] In a first aspect, the present application provides a control method for an energy storage system, wherein the energy storage system includes several first submodules; the method includes: when a second submodule including a battery cell is added to the energy storage system, obtaining a battery normalization scoring parameter of the second submodule; the battery normalization scoring parameter is a comprehensive scoring value characterizing the battery operating performance; and according to the battery normalization scoring parameter and a preset scoring limit, controlling the second submodule to remain in an engaged state or removing the second submodule.

[0006] In the above implementation process, for an energy storage system including several first submodules, when the second submodule is put into use, the normalized battery scoring parameter of the second submodule is obtained, and then the second submodule is controlled to maintain the put-in state or to be removed in combination with the preset scoring limit. The control of the second submodule is realized on the basis of fully considering the battery capacity of the second submodule, thereby realizing coordinated control of different submodules, so that the performance of the new submodule can be fully tested, which is conducive to the stable response of the whole system.

[0007] In some embodiments, the first submodule and the second submodule are energy storage submodules with different terminal voltages and different capacities.

[0008] In the above implementation process, an optional type of the second submodule is provided, that is, a submodule that is different from the original energy storage submodule in the energy storage system in terms of terminal voltage and capacity.

[0009] In some embodiments, the battery normalization score parameter is calculated based on at least two indicators of battery state of charge, battery health, battery current inconsistency, battery power capability, and a weight corresponding to each of the at least two indicators.

[0010] In the above implementation process, a specific method for calculating the normalized battery scoring parameters is provided.

[0011] In some embodiments, controlling the second submodule to remain in an engaged state or to remove the second submodule according to the battery normalized score parameter and a preset score limit includes: when the battery normalized score parameter is greater than the preset score limit, controlling the second submodule to remain in an engaged state; and when the battery normalized score parameter is not greater than the preset score limit, removing the second submodule.

[0012] In the above implementation process, a specific control strategy for the new sub-module is provided, namely, a maximum available control strategy. Through this strategy, the new sub-module can be utilized to the maximum extent possible and put into use as much as possible to support the bus voltage.

[0013] In some embodiments, controlling the second submodule to remain in an engaged state or to remove the second submodule according to the battery normalization score parameter and a preset score limit includes: when the battery normalization score parameter is greater than the preset score limit, controlling the second submodule to remain in an engaged state or to remove the second submodule at a set frequency.

[0014] In the above implementation process, another specific control strategy for the new submodule is provided, namely, a fixed frequency control strategy. Through this strategy, the new submodule is put into operation and removed at a set frequency, thereby better meeting the operation requirements of the actual energy storage valve project.

[0015] In some embodiments, the method further includes: acquiring the dynamic performance of the second submodule at different frequencies and the response of the energy storage system.

[0016] In the above implementation process, under the fixed frequency control strategy, the new sub-module will be put into operation and removed at a specific frequency, so the dynamic performance of the new sub-module at each frequency can be fully tested. At the same time, the response of the system when the new sub-module is switched on and off at different frequencies can also be tested, thereby providing convenient conditions for the improvement of the energy storage system.

[0017] In some embodiments, the controlling the second submodule to remain in the input state or to remove the second submodule according to the battery normalization score parameter and the preset score limit includes: executing a charging strategy when the initial charging current of the second submodule is greater than a charging threshold value; under the charging strategy, if the real-time charging current is not greater than the charging threshold value, removing the second submodule; if the real-time charging current is greater than the charging threshold value, executing a discharging strategy when the battery normalization score parameter is less than or equal to the preset score limit value; and controlling the second submodule to remain in the input state when the battery normalization score parameter is greater than the preset score limit value; executing a discharging strategy when the initial discharge current of the second submodule is greater than the discharge threshold value; under the discharge strategy, if the real-time discharge current is not greater than the discharge threshold value, removing the second submodule; and if the real-time discharge current is greater than the discharge threshold value, executing a charging strategy when the battery normalization score parameter is less than or equal to the preset score limit value; and controlling the second submodule to remain in the input state when the battery normalization score parameter is greater than the preset score limit value.

[0018] In the above implementation process, another specific control strategy is provided for the new sub-module, namely, the SOX full-operating condition control strategy. Through this strategy, the new sub-module can operate in the full scoring section of SOX, providing further convenient conditions for testing the battery performance of the new sub-module.

[0019] In some embodiments, the method further includes: after controlling the second submodule to maintain an on-state, calculating the required number of the first submodule to be on-state according to the real-time voltage of the second submodule and the average value of the capacitor voltage of the first submodule.

[0020] In the above implementation process, when a new sub-module is put into use, the number of existing sub-modules to be put into use is calculated based on the real-time voltage of the new sub-module and the average capacitor voltage of the existing sub-modules, so as to control the switching of the existing sub-modules, thereby minimizing the voltage fluctuation caused by the switching of the new sub-module with a larger port voltage.

[0021] In some embodiments, the calculation of the required number of inputs of the first submodule based on the real-time voltage of the second submodule and the average value of the capacitor voltage of the first submodule includes: dividing the difference obtained by subtracting the real-time voltage of the second submodule from the DC voltage modulation wave by the average value of the capacitor voltage of the first submodule to obtain the required number of inputs of the first submodule.

[0022] In the above implementation process, a specific method is provided for calculating the number of existing sub-modules that should be put into use when a new sub-module is put into use.

[0023] In a second aspect, the present application provides a control device for an energy storage system, wherein the energy storage system includes several first submodules; the device includes: an acquisition module, used to acquire a battery normalization score parameter of the second submodule when a second submodule including a battery cell is added to the energy storage system; the battery normalization score parameter is a comprehensive score value characterizing the battery operating performance; a control module, used to control the second submodule to remain in an engaged state or to remove the second submodule according to the battery normalization score parameter and a preset score limit.

[0024] In a third aspect, the present application provides an electronic device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the method described in any one of the first aspects are implemented.

[0025] In a fourth aspect, the present application provides an energy storage system, including an energy storage unit and a control unit; the control unit adopts the electronic device described in the third aspect.

[0026] In a fifth aspect, the present application provides a computer-readable storage medium having instructions stored thereon. When the instructions are executed on a computer, the computer executes the method as described in any one of the first aspects.

[0027] In a sixth aspect, the present application provides a computer program product, which, when executed on a computer, enables the computer to execute the method as described in any one of the first aspects.

[0028] Other features and advantages disclosed in the present application will be described in the following description, or some features and advantages can be inferred or determined without doubt from the description, or can be learned by implementing the above-mentioned technology disclosed in the present application.

[0029] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] 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. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A schematic diagram of adding a single new submodule to an existing DC energy storage valve test provided in some embodiments of the present application;

[0032] Figure 2 A flow chart of a control method for an energy storage system provided in some embodiments of the present application;

[0033] Figure 3 A schematic diagram of a process for maximizing available control strategies provided in some embodiments of the present application;

[0034] Figure 4 A schematic diagram of a process of a fixed frequency control strategy provided in some embodiments of the present application;

[0035] Figure 5 A schematic diagram of a process of a SOX full-operating condition control strategy provided in some embodiments of the present application;

[0036] Figure 6 A block diagram of a control device for an energy storage system provided in some embodiments of the present application;

[0037] Figure 7 A structural block diagram of an electronic device provided for some embodiments of the present application. DETAILED DESCRIPTION

[0038] 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.

[0039] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0040] At present, the direct-mounted energy storage power change system has attracted wide attention in high-voltage and large-capacity applications. In actual projects, before the energy storage valve composed of new sub-modules is put into use, a single new sub-module will be added to the existing energy storage valve for performance testing, such as Figure 1 As shown, Figure 1It is a schematic diagram of a test of adding a single new submodule to an existing DC energy storage valve. The DC energy storage valve includes several existing submodules 11. After the new submodule 12 is put into use, the energy storage system is composed of different types of submodules. The current control method mainly uses the original control strategy for the existing submodule to control the new submodule. However, the new submodule and the existing submodule often have differences in capacity, voltage level, etc. Therefore, this control method cannot fully test the performance of the new submodule, and is also not conducive to the overall stable response of the system.

[0041] In response to the above technical problems, an embodiment of the present application provides a control method for an energy storage system. When the energy storage system is put into use with a second submodule, the normalized battery scoring parameter of the second submodule is obtained, and then the switching of the second submodule is controlled in combination with a preset scoring limit. In this way, by adding a control strategy for the second submodule, coordinated control of different submodules is achieved, so that the performance of the new submodule can be fully tested, which is conducive to the stable response of the system as a whole.

[0042] Next, the embodiments of the present application are introduced:

[0043] like Figure 2 As shown, Figure 2 This is a flow chart of a control method of an energy storage system provided in an embodiment of the present application, wherein the energy storage system may have an energy storage structure based on a DC direct-connection topology. The energy storage system includes a plurality of first submodules, which may be half-bridge energy storage submodules or full-bridge energy storage submodules.

[0044] The method comprises:

[0045] Step 201: When a second submodule including a battery cell is added to the energy storage system, a battery normalization scoring parameter of the second submodule is obtained; the battery normalization scoring parameter is a comprehensive scoring value characterizing the battery operating performance;

[0046] The second submodule mentioned in this step is an energy storage submodule including a battery cell. Each energy storage submodule may include a power module part consisting of a half-bridge or full-bridge structure, a module voltage-equalizing capacitor, and a voltage-equalizing resistor, a battery starting resistance circuit part, a battery module (consisting of several battery cells), and a bypass switch. In some embodiments, the first submodule and the second submodule are energy storage submodules with different terminal voltages and different capacities in the local area. In other words, the second submodule may be an energy storage submodule that is different from the original first submodule in the energy storage system in terms of terminal voltage and capacity, which can be considered as a new submodule, and accordingly, the first submodule may also be referred to as an existing submodule. Optionally, the terminal voltage of the second submodule is higher than the terminal voltage of the first submodule; the capacity of the second submodule is greater than the capacity of the first submodule. In other words, the second submodule has a higher nominal port voltage and a larger battery capacity than the first submodule, so the second submodule may be a submodule suitable for higher voltage level engineering, so that the energy storage system can be promoted to develop in the direction of high voltage and large capacity.

[0047] In addition, in actual applications, when a certain energy storage submodule in the energy storage system fails and is then repaired and rejoined to the energy storage system, at this time, there are differences between the energy storage submodule and other submodules on the energy storage system in terms of terminal voltage, capacity, etc., then the energy storage submodule can also be considered as the second submodule, and the other submodules on the energy storage system are the first submodules.

[0048] In this embodiment, when the second submodule is added to the energy storage system, the battery normalization scoring parameter of the second submodule can be obtained to control the switching of the second submodule. The battery normalization scoring parameter can be recorded as SOX, which is a comprehensive scoring value that characterizes the battery operating performance. That is to say, the higher the SOX value of the second submodule, the more suitable the second submodule is for investment. In some embodiments, the battery normalization scoring parameter can be calculated based on at least two indicators of battery state of charge, battery health, battery current inconsistency, and battery power capability, and the weight corresponding to each of the at least two indicators. These indicators are all important indicators that affect battery performance, and they can all be calculated through corresponding algorithms or models. For example, the battery state of charge (SOC) can be calculated based on the ampere-hour integration method or the Kalman filter algorithm; the battery health (SOH) can be calculated by the SOH estimation model, which generally calculates the battery internal resistance based on the current and voltage, and then evaluates the current battery health status based on the internal resistance of the corresponding state; the battery current inconsistency can be obtained by dividing the difference between the maximum current and the minimum current by the average current; the battery power capacity is affected by the battery temperature and the battery current, and there is a corresponding relationship. Therefore, a calculation model that characterizes the corresponding relationship between the battery power capacity and the battery temperature and the battery current can be established through testing. When implemented, the calculation model is used to calculate the battery power capacity of the second submodule based on the real-time battery temperature and the real-time battery current. The weight corresponding to each indicator can be determined according to the importance of each indicator in the high-voltage and large-capacity energy storage system. Of course, in other embodiments, the battery normalization scoring parameter can also be calculated based on other indicators, such as battery voltage, battery temperature, etc.

[0049] Step 202: Control the second submodule to remain in the activated state or remove the second submodule according to the battery normalized scoring parameter and a preset scoring limit.

[0050] The preset score limit mentioned in this step can be a preset SOX lower limit, which can be set by testing the response fluctuation of the energy storage system after putting submodules with different SOX values ​​into the energy storage system in the experiment, and combining the needs of the specific scenario. When the battery normalization score parameter of any submodule, that is, the SOX value, drops to the SOX lower limit, it indicates that the submodule is not suitable for investment in the energy storage system. Therefore, according to the battery normalization score parameter of the second submodule and the preset score limit, the second submodule is controlled to remain in the investment state or the second submodule is removed, so as to realize the control of the second submodule on the basis of fully considering the battery capacity of the second submodule, while for the control of the first submodule, the original control strategy can still be maintained, so as to realize the coordinated control of different submodules.

[0051] According to the different performance test requirements of new sub-modules, the control strategy of new sub-modules can be further subdivided as follows:

[0052] In some embodiments, this step may include: when the battery normalization score parameter is greater than the preset score limit, control the second submodule to remain in the input state; when the battery normalization score parameter is not greater than the preset score limit, remove the second submodule. This is a control strategy to achieve maximum available control. When the SOX value of the new submodule is greater than the SOX lower limit, the new submodule is kept in the input state. Conversely, when the SOX value of the new submodule is less than or equal to the SOX lower limit, the new submodule is removed. In this way, the new submodule can be maximized and put into use as much as possible to support the bus voltage. Moreover, in this strategy, the new submodule is put into use for a long time, and its charging and discharging state performance can be fully tested.

[0053] In some embodiments, this step may include: when the battery normalization score parameter does not exceed the preset score limit, the second submodule is controlled to remain in the input state or the second submodule is removed at a set frequency. This is a control strategy for implementing fixed frequency control. When the SOX of the new submodule is greater than the SOX lower limit, the power electronic switch device of the new submodule is input with a set frequency of on and off pulses, so that the new submodule is put into and removed at the set frequency, so that the operation requirements of the actual project of the energy storage valve can be better met. In this strategy, the control method of the present application may also include: obtaining the dynamic performance of the second submodule at different frequencies and the response of the energy storage system. That is to say, under the fixed frequency control strategy, the new submodule will be put into and removed at a specific frequency, so that the dynamic performance of the new submodule at each frequency can be fully tested, such as loss, junction temperature fluctuation, thermal effect, peak voltage current, etc. At the same time, the response of the system when the new submodule is switched at different frequencies can also be tested, thereby providing convenient conditions for the improvement of the energy storage system.

[0054] In some embodiments, this step may include: executing a charging strategy when the initial charging current of the second submodule is greater than a charging threshold value; under the charging strategy, if the real-time charging current is not greater than the charging threshold value, cutting off the second submodule; if the real-time charging current is greater than the charging threshold value, executing a discharging strategy when the battery normalization scoring parameter is less than or equal to a preset scoring limit; and controlling the second submodule to remain in an engaged state when the battery normalization scoring parameter is greater than the preset scoring limit; executing a discharging strategy when the initial discharge current of the second submodule is greater than the discharge threshold value; under the discharge strategy, if the real-time discharge current is not greater than the discharge threshold value, cutting off the second submodule; and if the real-time discharge current is greater than the discharge threshold value, executing a charging strategy when the battery normalization scoring parameter is less than or equal to the preset scoring limit; and controlling the second submodule to remain in an engaged state when the battery normalization scoring parameter is greater than the preset scoring limit. This is a control strategy for achieving full-operating-condition control of SOX. Since the capacity of the new submodule is large, its SOX changes more slowly than that of the existing submodule. Therefore, when the SOX value of the existing submodule drops to the limit value, the SOX of the new submodule often has a certain margin. Therefore, the full-operating-condition control strategy of SOX is designed. First, the initial charge and discharge state of the current submodule is judged according to whether the charge and discharge current is greater than the preset current threshold value. The strategy will lock a state, that is, the charging state or the discharging state. Taking the charging state as an example, when the initial charging current of the new submodule is greater than the charging threshold value, the system determines that the initial state of the new submodule is the charging state and locks the charging strategy. When the subsequent real-time charging current is greater than the charging threshold value, the new submodule is put into operation. When the subsequent real-time charging current is less than or equal to the charging threshold value, the new submodule is removed until the SOX value of the new submodule drops to the SOX lower limit value. The strategy is converted to a discharge strategy and locked, and this cycle continues. In this way, the new submodule can be operated in the full scoring section of SOX, providing further convenient conditions for testing the battery performance of the new submodule.

[0055] Of course, in addition to the above three specific control strategies, different control strategies can also be set according to other performance test requirements of the new sub-module, and this application does not impose any restrictions on this.

[0056] Furthermore, in some embodiments, the control method of the present application may further include: after controlling the second submodule to maintain the input state, the required number of the first submodule to be input is calculated according to the real-time voltage of the second submodule and the average capacitor voltage of the first submodule. That is, when a new submodule is put into operation, the number of existing submodules to be put into operation is calculated according to the real-time voltage of the new submodule and the average capacitor voltage of the existing submodules, so as to control the switching of the existing submodules, thereby minimizing the voltage fluctuation caused by switching the new submodule with a larger port voltage.

[0057] Furthermore, the aforementioned calculation of the required number of first submodules to be invested based on the real-time voltage of the second submodule and the average value of the capacitor voltage of the first submodule may include: dividing the difference obtained by subtracting the real-time voltage of the second submodule from the DC voltage modulation wave by the average value of the capacitor voltage of the first submodule to obtain the required number of first submodules to be invested. In other words, the number of existing submodules to be invested = (DC voltage modulation wave - real-time voltage of new submodule) / average value of capacitor voltage of existing submodules, so that the number of existing submodules to be invested in the case of investing in new submodules can be quickly calculated.

[0058] In the embodiment of the present application, for an energy storage system including several first submodules, when a second submodule is put into use, the normalized battery scoring parameter of the second submodule is obtained, and then the second submodule is controlled to maintain the put-in state or to be removed in combination with a preset scoring limit. The control of the second submodule is achieved on the basis of fully considering the battery capacity of the second submodule, thereby achieving coordinated control of different submodules, so that the performance of the new submodule can be fully tested, which is conducive to the stable response of the system as a whole.

[0059] In order to explain the solution of this application in more detail, a specific embodiment is introduced below:

[0060] In this embodiment, a single new submodule is added to the existing energy storage valve for performance testing. The existing energy storage valve originally contains several existing submodules, wherein the port voltage of the new submodule is 2.5kV, which is higher than the port voltage of the existing submodule of 1.5kV. Therefore, for the convenience of distinction, the new submodule is referred to as the 2.5kV submodule and the existing submodule is referred to as the 1.5kV submodule. Before the 2.5kV submodule is added, the control strategy of the energy storage valve for the 1.5kV submodule is to determine the number of battery modules that should be invested in the system in the current control cycle based on the reference voltage and the average capacitance voltage of the submodule, and then determine the specific submodules to be balanced by the system in the current control cycle and switch them on and off in combination with the number of submodules required to be invested in the previous cycle. Considering that after the addition of the 2.5kV submodule, the existing energy storage valve is composed of different types of submodules, therefore, this embodiment provides a coordinated control strategy for different submodules based on a high-voltage and large-capacity energy storage system, so that the performance of the new submodule can be fully tested, and the bus voltage fluctuation is within a safe range. The scheme of this embodiment is divided into the following two parts:

[0061] Part 1 is to divide the control strategies of new submodules into three types according to different performance test requirements of new submodules, namely, maximum available control strategy, fixed frequency control strategy and SOX full-operating condition control strategy; among them:

[0062] The process of maximizing the available control strategies is as follows Figure 3 As shown, the process includes:

[0063] S301, determine whether the SOX value of the 2.5kV submodule is less than or equal to the SOX lower limit value, if yes, execute S302, otherwise execute S303;

[0064] S302, remove the 2.5kV submodule;

[0065] S303, put into operation the 2.5 kV submodule.

[0066] The process of the fixed frequency control strategy is as follows Figure 4 As shown, the process includes:

[0067] S401, setting the switching frequency of the 2.5 kV submodule to x Hz; where x represents a certain value;

[0068] S402, determine whether the SOX value of the 2.5kV submodule is less than or equal to the SOX lower limit value, if yes, execute S403, otherwise execute S404;

[0069] S403, remove the 2.5kV submodule;

[0070] S404, switching on and off the 2.5 kV submodule at a frequency of x Hz.

[0071] The process of SOX full-condition control strategy is as follows Figure 5 As shown, the process includes:

[0072] S501, determine whether the initial state of the 2.5kV submodule is charging, if yes, execute S502, otherwise execute S503;

[0073] S502, determining whether the initial charging current of the 2.5 kV submodule is greater than the charging threshold value, if yes, executing S504, otherwise executing S512;

[0074] S503, determine whether the initial discharge current of the 2.5 kV submodule is greater than the discharge threshold value, if yes, execute S509, otherwise execute S512;

[0075] S504, entering charging strategy;

[0076] S505, determining whether the real-time charging current of the 2.5 kV submodule is greater than the charging threshold value, if yes, executing S506, otherwise executing S507;

[0077] S506, determine whether the SOX value of the 2.5kV submodule in the charging state is less than or equal to the SOX lower limit value, if yes, execute S509, otherwise execute S508;

[0078] S507, remove the 2.5kV submodule;

[0079] S508, put into use 2.5kV submodule;

[0080] S509, entering the discharge strategy;

[0081] S510, determining whether the real-time discharge current of the 2.5 kV submodule is greater than the discharge threshold value, if yes, executing S511, otherwise executing S507;

[0082] S511, determine whether the SOX value of the 2.5 kV submodule in the discharge state is less than or equal to the SOX lower limit value, if yes, execute S504, otherwise execute S508;

[0083] S512, control the 2.5kV submodule to maintain its original state.

[0084] The second part is to coordinate the control strategy, combining the original control strategy with the control strategy of the new sub-module. According to whether the new sub-module is put into use, the number of existing sub-modules that should be put into use is calculated respectively, so as to minimize the voltage fluctuation caused by the new sub-module with a larger port voltage. Specifically, when the new sub-module is not put into use, the original control strategy is maintained; when the new sub-module is put into use, the DC voltage modulation wave is subtracted from the real-time voltage of the new sub-module, and then divided by the average capacitor voltage of the existing sub-module to calculate the number of existing sub-modules to be put into use, and then the new sub-module control strategy is adopted according to the different test requirements of the new sub-module.

[0085] Corresponding to the embodiments of the aforementioned method, the present application also provides embodiments of a control device for an energy storage system and a terminal used therein:

[0086] like Figure 6 As shown, Figure 6 is a block diagram of a control device of an energy storage system provided in an embodiment of the present application, wherein the energy storage system includes a plurality of first submodules; the device includes:

[0087] An acquisition module 61 is used to acquire a battery normalization scoring parameter of a second submodule including a battery unit when the energy storage system is added with the second submodule; the battery normalization scoring parameter is a comprehensive scoring value characterizing the battery operating performance;

[0088] The control module 62 is used to control the second submodule to maintain the activated state or to cut off the second submodule according to the battery normalized scoring parameter and a preset scoring limit.

[0089] The implementation process of the functions and effects of each module in the above-mentioned device is specifically described in the implementation process of the corresponding steps in the above-mentioned method, which will not be repeated here.

[0090] This application also provides an electronic device, see Figure 7 , Figure 7 A block diagram of an electronic device provided in an embodiment of the present application. The electronic device may include a processor 710, a communication interface 720, a memory 730, and at least one communication bus 740. The communication bus 740 is used to realize direct connection and communication between these components. The communication interface 720 of the electronic device in the embodiment of the present application is used to communicate signaling or data with other node devices. The processor 710 may be an integrated circuit chip with signal processing capabilities.

[0091] The processor 710 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. The processor 710 may be a microprocessor, or the processor 710 may be any conventional processor, etc.

[0092] The memory 730 may be, but is not limited to, a random access memory (RAM), a read only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electric erasable programmable read-only memory (EEPROM), etc. The memory 730 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 710, the electronic device can execute the above-mentioned Figure 1 The method embodiment involves various steps.

[0093] Optionally, the electronic device may further include a storage controller and an input / output unit.

[0094] The memory 730, storage controller, processor 710, peripheral interface, input and output unit components are directly or indirectly electrically connected to each other to achieve data transmission or interaction. For example, these components can be electrically connected to each other via one or more communication buses 740. The processor 710 is used to execute executable modules stored in the memory 730, such as software function modules or computer programs included in the electronic device.

[0095] The input and output unit is used to provide users with the task creation and to create a start optional time period or preset execution time for the task to realize the interaction between the user and the server. The input and output unit can be, but is not limited to, a mouse and a keyboard.

[0096] Understandably, Figure 7 The structure shown is for illustration only, and the electronic device may also include Figure 7 More or fewer components as shown, or with Figure 7 Different configurations are shown. Figure 7 Each component shown in the figure can be implemented by hardware, software or a combination thereof.

[0097] The present application provides an energy storage system, which includes an energy storage unit and a control unit; the control unit adopts Figure 7 Electronic equipment shown.

[0098] An embodiment of the present application further provides a storage medium having instructions stored thereon. When the instructions are run on a computer, the computer program is executed by a processor to implement the method described in the method embodiment. To avoid repetition, the method will not be described here.

[0099] The present application also provides a computer program product, which, when executed on a computer, enables the computer to execute the method described in the method embodiment.

[0100] 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.

[0101] 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.

[0102] 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 storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned 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.

[0103] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0104] 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.

[0105] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

Claims

1. A control method for an energy storage system, characterized in that: The energy storage system includes a plurality of first submodules; the method includes: In the case where a second submodule including a battery cell is added to the energy storage system, a battery normalization scoring parameter of the second submodule is obtained; the battery normalization scoring parameter is a comprehensive scoring value characterizing the battery operating performance; According to the battery normalized scoring parameter and a preset scoring limit, the second submodule is controlled to remain in an engaged state or to be removed.

2. The method according to claim 1, characterized in that The first submodule and the second submodule are energy storage submodules with different terminal voltages and different capacities.

3. The method according to claim 1 or 2, characterized in that: The battery normalization scoring parameter is calculated based on at least two indicators of battery state of charge, battery health, battery current inconsistency, and battery power capability, and a weight corresponding to each of the at least two indicators.

4. The method according to any one of claims 1 to 3, characterized in that: The controlling the second submodule to maintain the input state or to remove the second submodule according to the battery normalization score parameter and the preset score limit value includes: When the battery normalization score parameter is greater than a preset score limit, controlling the second submodule to remain in an engaged state; When the battery normalized score parameter is not greater than a preset score limit, the second submodule is cut off.

5. The method according to any one of claims 1 to 3, characterized in that: The controlling the second submodule to maintain the input state or to remove the second submodule according to the battery normalization score parameter and the preset score limit value includes: When the battery normalization score parameter is greater than a preset score limit, the second submodule is controlled to remain in the activated state or to be removed at a set frequency.

6. The method according to claim 5, characterized in that The method further comprises: The dynamic performance of the second submodule at different frequencies and the response of the energy storage system are obtained.

7. The method according to any one of claims 1 to 3, characterized in that: The controlling the second submodule to maintain the input state or to remove the second submodule according to the battery normalization score parameter and the preset score limit value includes: In the case where the initial charging current of the second submodule is greater than the charging threshold value, a charging strategy is executed; under the charging strategy, if the real-time charging current is not greater than the charging threshold value, the second submodule is removed; if the real-time charging current is greater than the charging threshold value, a discharging strategy is executed when the battery normalization scoring parameter is less than or equal to a preset scoring limit value; and when the battery normalization scoring parameter is greater than the preset scoring limit value, the second submodule is controlled to remain in an engaged state; When the initial discharge current of the second submodule is greater than the discharge threshold value, the discharge strategy is executed; under the discharge strategy, if the real-time discharge current is not greater than the discharge threshold value, the second submodule is cut off; if the real-time discharge current is greater than the discharge threshold value, when the battery normalization score parameter is less than or equal to the preset score limit value, the charging strategy is executed; when the battery normalization score parameter is greater than the preset score limit value, the second submodule is controlled to remain in the engaged state.

8. The method according to any one of claims 1 to 7, characterized in that: The method further comprises: After controlling the second submodule to maintain the input state, the input requirement quantity of the first submodule is calculated according to the real-time voltage of the second submodule and the average value of the capacitor voltage of the first submodule.

9. The method according to claim 8, characterized in that The step of calculating the required input quantity of the first submodule according to the real-time voltage of the second submodule and the average value of the capacitor voltage of the first submodule includes: The difference obtained by subtracting the real-time voltage of the second submodule from the DC voltage modulation wave is divided by the average value of the capacitor voltage of the first submodule to obtain the required input quantity of the first submodule.

10. A control device for an energy storage system, characterized in that: The energy storage system includes a plurality of first submodules; the device includes: An acquisition module, configured to acquire a battery normalization scoring parameter of the second submodule when the energy storage system is added with a second submodule including a battery cell; the battery normalization scoring parameter is a comprehensive scoring value characterizing the battery operating performance; The control module is used to control the second submodule to maintain the input state or cut off the second submodule according to the battery normalization score parameter and the preset score limit.

11. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the method according to any one of claims 1 to 9 is implemented.

12. An electronic device, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

13. An energy storage system, characterized in that: The energy storage system includes an energy storage unit and a control unit; the control unit adopts the electronic device as claimed in claim 12.

Images