Charging and discharging control method of energy storage system

Abstract

The invention discloses a charging and discharging control method of an energy storage system. The charging and discharging control method comprises the following steps: dynamically adjusting a charging and discharging instruction of the energy storage system according to the used capacity of the energy storage system, the electricity load and power at the current moment and the matching relationship between the electricity load and the energy storage system; and in response to a charge-discharge instruction of which the charge-discharge power is greater than or equal to a preset threshold value in the charge-discharge instructions, executing a local equalization strategy on the battery systems related to the charge-discharge instruction of which the charge-discharge power is greater than or equal to the preset threshold value, so as to eliminate the energy difference among the battery systems related to the charge-discharge instruction. In this way, the stability and the service life of the energy storage battery can be improved.

Description

Technical Field

[0001] The present application relates to the field of energy storage systems, and in particular to a charging and discharging control method for energy storage systems. Background Art

[0002] During the charging and discharging process of the energy storage system, due to the differences between the individual battery cells, the overall charging and discharging control method is prone to cause excessive charging and discharging of certain battery cells or modules; excessive charging and discharging between battery cells leads to internal energy imbalance of the entire energy storage device, which not only shortens the life of the battery cells, but also affects the charging and discharging power of the entire energy storage device. Summary of the invention

[0003] The present application mainly provides a charge and discharge control method for an energy storage system to solve the problem of reduced stability and life of energy storage batteries.

[0004] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a charge and discharge control method for an energy storage system, comprising: dynamically adjusting the charge and discharge instructions of the energy storage system according to the used capacity of the energy storage system, the electrical load and power at the current moment, and the matching relationship between the electrical load and the energy storage system; in response to the presence of a charge and discharge instruction in which the charge and discharge power is greater than or equal to a preset threshold value in the charge and discharge instructions, executing a local balancing strategy for the battery system related to the charge and discharge instruction that is greater than or equal to the preset threshold value, so as to eliminate the energy difference between the battery systems related to the charge and discharge instructions.

[0005] In some embodiments, in response to the presence of a charge and discharge instruction with a charge and discharge power greater than or equal to a preset threshold among the charge and discharge instructions, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold to eliminate the energy difference between the battery systems related to the charge and discharge instructions, including: in response to the presence of a charge and discharge instruction with a charge and discharge power greater than or equal to the preset threshold among the charge and discharge instructions, continuously acquiring state parameters of the relevant battery systems; generating the local balancing strategy for the relevant battery systems based on the state parameters; and executing active local balancing between the relevant battery systems or within the battery packs according to the local balancing strategy.

[0006] In some embodiments, the local balancing strategy for each of the battery systems generated based on the state parameters includes: calculating the difference in state of charge between the battery systems; calculating the charge and discharge power that needs to be increased or decreased for each of the battery systems based on the difference, so as to configure the balancing time, balancing speed and balancing control method of the local balancing strategy.

[0007] In some embodiments, the formula for calculating the state of charge is:

[0008] Among them, SOCt is the current state of charge of the battery system, SOCf is the initial state of charge of the battery system, ∫Idt is the current integral of the battery system within the target time, and C is the total capacity of the battery system in a fully charged state.

[0009] In some embodiments, the active local balancing between the relevant battery systems is performed according to the local balancing strategy, including: transferring energy from the battery system with a high state of charge to the battery system with a low state of charge in each of the battery systems according to the local balancing strategy, or transferring energy from a battery group with a high charge state to a battery group with a low charge state in each of the battery systems; in response to the difference in charge state between the battery systems being less than a preset difference threshold, ending the active local balancing.

[0010] In some embodiments, in response to the presence of a charge and discharge instruction in which the charge and discharge power is greater than or equal to a preset threshold value, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold value to eliminate the energy difference between the battery systems related to the charge and discharge instructions, and also includes: in response to a change in the state parameter, the local balancing strategy is updated to adjust the battery system performing the charge state transfer and the transferred energy.

[0011] In some embodiments, the state parameters of the battery system include: voltage, current, temperature, internal resistance, and charge and discharge state.

[0012] In some embodiments, dynamically adjusting the charge and discharge instructions of the energy storage system according to the used capacity of the energy storage system, the electrical load and power at the current moment, and the matching relationship between the electrical load and the energy storage system includes: monitoring the temperature of each of the energy storage systems, and adjusting the power value of the charge and discharge instructions according to the change in the temperature.

[0013] In order to solve the above technical problems, another technical solution adopted by the present application is: providing a storage medium on which program data is stored, characterized in that when the program data is executed by a processor, the steps of the charge and discharge control method as described above are implemented.

[0014] The present application also provides a computer device, characterized in that it includes a processor and a memory connected to each other, the memory stores a computer program, and when the processor executes the computer program, the steps of the charge and discharge control method as described above are implemented.

[0015] The beneficial effects of the present application are as follows: Different from the prior art, the present application discloses a charge and discharge control method, storage medium and computer equipment for an energy storage system. The charge and discharge instructions of the energy storage system are dynamically adjusted according to the used capacity of the energy storage system, the current electrical load and power, and the matching relationship between the electrical load and the energy storage system; by dynamically adjusting the charge and discharge instructions of the energy storage system, it is possible to ensure that the energy storage system is charged or discharged at the appropriate time, thereby making full use of electrical energy, and helping to balance the load of the power grid and improve energy utilization efficiency. In response to the presence of a charge and discharge instruction with a charge and discharge power greater than or equal to a preset threshold in the charge and discharge instruction, a local balancing strategy is executed for the battery system related to the charge and discharge instruction greater than or equal to the preset threshold to eliminate the energy difference between the battery systems related to the charge and discharge instruction; the local balancing strategy can ensure that the voltage between the individual cells in the battery pack remains consistent during the charge and discharge process. This helps to reduce the energy loss caused by energy differences within the battery pack, thereby improving the overall performance of the battery pack. By reducing the imbalance phenomenon within the battery pack, the local balancing strategy can also reduce the aging rate of the battery pack, reduce the replacement cost caused by the degradation of battery performance, and improve the stability and life of the energy storage battery. BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which: Figure 1 It is a flow chart of an embodiment of a method for controlling charging and discharging of an energy storage system of the present application; Figure 2 Yes Figure 1 The flowchart of the embodiment of step 20 of the method is shown; Figure 3 Yes Figure 2 The flowchart of the embodiment of step 22 of the method shown; Figure 4 Yes Figure 2 The flowchart of the embodiment of step 23 of the method shown; Figure 5 It is a structural schematic diagram of an embodiment of a storage medium provided by the present application; Figure 6 It is a structural diagram of an embodiment of a computer device provided by the present application. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] The terms "first", "second", "third" in the embodiments of the present application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0018] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0019] See also Figure 1 , Figure 1 1 is a flow chart of an embodiment of a charge and discharge control method of an energy storage system of the present application, and the charge and discharge control method includes: Step 10: Dynamically adjust the charge and discharge instructions of the energy storage system according to the used capacity of the energy storage system, the current power load and power, and the matching relationship between the power load and the energy storage system.

[0020] The used capacity of the energy storage system is an important basis for adjusting the charge and discharge instructions. When the used capacity is high, the system may need more charging to replenish energy; when the used capacity is low, the system may be more inclined to discharge to meet the current power demand.

[0021] Specifically, if the used capacity of the energy storage system is high, it means that the system needs to replenish energy as soon as possible. At this time, charging instructions should be given priority, especially during low electricity price periods or when renewable energy generation is sufficient, to restore the system's energy storage level through charging.

[0022] If the used capacity is low, the system may have enough energy to meet the current electricity demand or future peak demand. In this case, more consideration can be given to discharge instructions, especially during peak electricity price periods or peak grid load periods, to release energy and obtain economic benefits through discharge.

[0023] The current power load and power are also key factors in adjusting the charge and discharge instructions. By monitoring the power load and power in real time, the charge and discharge strategy of the energy storage system can be matched more accurately.

[0024] If the current power load is high and the power is large, it means that the grid or the user is facing a large power demand. At this time, the energy storage system should give priority to discharge instructions to supplement the shortage of the grid or meet the power demand of the user. At the same time, it is also necessary to pay attention to the remaining capacity of the energy storage system to ensure that the system's energy storage is not over-consumed during the discharge process.

[0025] On the contrary, if the current power load is low and the power is small, it means that the power demand of the power grid or users is relatively small. At this time, the energy storage system considers charging instructions more, especially during the low electricity price period or when renewable energy generation is sufficient, to store energy for future use through charging.

[0026] The matching relationship between the power load and the energy storage system is also an important consideration for adjusting the charge and discharge instructions. By optimizing the matching relationship, the efficiency and performance of the energy storage system can be further improved.

[0027] Specifically, if the power load and the energy storage system are highly matched, it means that the energy storage system can meet the power demand more effectively. In this case, the charge and discharge instructions can be adjusted more flexibly to maximize the economic benefits and performance of the system. For example, during peak load periods or peak electricity price periods, discharge instructions can be given priority; while during low load periods or low electricity price periods, charging instructions can be given priority.

[0028] On the contrary, if the power load and the energy storage system are poorly matched, it is necessary to comprehensively consider factors such as the system's energy storage level, power demand, and electricity prices to ensure stable operation of the system and maximize benefits.

[0029] Optionally, dynamic adjustment of charge and discharge instructions can be achieved through an energy storage management system (EMS) or a battery management system (BMS). The system can monitor the state of the energy storage system, power load, electricity price and other information in real time, and automatically adjust the charge and discharge instructions according to a preset strategy or algorithm.

[0030] Energy Storage Management System (EMS): EMS usually has multiple control strategies such as peak shaving, power fluctuation smoothing, backup power supply and demand response. By selecting the appropriate control strategy and setting the corresponding parameters, EMS can automatically adjust the charging and discharging instructions of the energy storage system to meet the current power demand and grid requirements.

[0031] Battery Management System (BMS): BMS is mainly responsible for monitoring the status of the battery and controlling the charging and discharging process. By optimizing the BMS strategy, it is possible to achieve fine control of the charging and discharging currents, and dynamically adjust the charging and discharging instructions according to the real-time status of the battery (such as temperature, voltage, internal resistance, etc.) to ensure that the battery operates in the best condition.

[0032] By real-time monitoring of the used capacity of the energy storage system and the current power load, the charging and discharging timing and power of the energy storage system can be accurately controlled to avoid unnecessary energy waste. During peak power load periods, the energy storage system can discharge to meet peak demand, and during off-peak periods it can charge to store excess power, thereby achieving efficient use of energy.

[0033] Furthermore, step 10 also includes: monitoring the temperature of each energy storage system, and adjusting the power value of the charge and discharge instruction according to the temperature change.

[0034] According to the specific situation of the energy storage system and the characteristics of the battery, set a reasonable temperature threshold. For example, the high temperature threshold can be set to 45°C and the low temperature threshold can be set to 0°C. Use temperature sensors and other equipment to monitor the temperature of the energy storage system in real time to ensure the accuracy and real-time nature of the data.

[0035] When the temperature reaches or exceeds the high temperature threshold, the charging and discharging power is automatically reduced to reduce the heat generated by the battery and prevent the temperature from continuing to rise. When the temperature drops below the low temperature threshold, the charging power can be appropriately increased to increase the battery temperature.

[0036] By setting reasonable temperature thresholds, monitoring temperature in real time, and adjusting charging and discharging power according to temperature changes, the impact of abnormal battery temperature on the energy storage system can be effectively reduced, and the stability and safety of the system can be improved.

[0037] Step 20: In response to the presence of a charge and discharge instruction in which the charge and discharge power is greater than or equal to a preset threshold, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold to eliminate the energy difference between the battery systems related to the charge and discharge instruction.

[0038] In energy storage systems, due to manufacturing differences between battery cells or battery modules, differences in usage environments, and inconsistencies in the charging and discharging process, there will be energy differences between battery systems. If this energy difference is not controlled, it will accelerate battery aging and reduce the overall performance of the energy storage system. Therefore, when the power of the charge and discharge instructions reaches or exceeds the preset threshold, a local balancing strategy is executed on the relevant battery system to reduce or eliminate this energy difference, thereby maintaining the consistency of the battery system.

[0039] Specifically, the voltage of each battery system is monitored in real time, and the energy difference between them is calculated. When it is found that the energy difference exceeds the set threshold, the local balancing strategy is triggered.

[0040] According to the specific situation of the battery system and the balancing requirements, select the appropriate balancing method, such as energy transfer balancing and energy consumption balancing; energy transfer balancing achieves balancing by transferring the energy of the high-voltage battery system to the low-voltage battery system; energy consumption balancing achieves balancing by consuming the excess energy of the high-voltage battery system.

[0041] According to the selected balancing method, the corresponding balancing operation is performed, and during the balancing process, the voltage changes of each battery system are continuously monitored.

[0042] Further, see Figure 2 , step 20 further includes: Step 21: In response to the presence of a charge / discharge instruction in which the charge / discharge power is greater than or equal to a preset threshold value, continuously acquiring state parameters of each related battery system.

[0043] Through sensors installed at key locations of the battery system, such as voltage sensors, current sensors, and temperature sensors, various status parameters of the battery system are monitored in real time. The data monitored by the sensors are collected in real time and transmitted to the data processing center for processing and analysis to extract useful status parameter information.

[0044] By analyzing the changing trends of parameters such as voltage, current, and temperature, it is possible to determine whether the battery system has problems such as aging, overheating, overcharging, and over-discharging.

[0045] Specifically, the state parameters of the battery system include: voltage, current, temperature, internal resistance, and charge and discharge state.

[0046] Step 22: Generate a local balancing strategy for each related battery system based on the state parameters.

[0047] For energy storage system cells or modules with large energy differences, an energy transfer equalizer is used to transfer the energy of the high-voltage battery to the low-voltage battery. When the energy difference exceeds the threshold, the equalization process is started until the energy difference is reduced to the allowable range.

[0048] In the case of uneven current distribution, the charging and discharging strategies can be adjusted to ensure even current distribution.

[0049] For cells or modules with large capacity differences, capacity recovery technology or replacement strategies are used to improve the overall capacity of the battery pack. At the same time, the battery system is regularly tested for capacity to evaluate the health status and service life of the battery pack.

[0050] Further, see Figure 3 , step 22 comprises: Step 221: Calculate the state of charge difference between each battery system.

[0051] The state of charge (SOC) value of each battery system is obtained through the battery management system or fuel gauge. These systems are usually able to monitor the status of the battery in real time and calculate the SOC. Estimation methods such as open circuit voltage method, coulomb counting method or dynamic voltage algorithm are used. These methods need to be estimated based on battery voltage, current, temperature and other parameters.

[0052] Specifically, the formula for calculating the state of charge is:

[0053] Among them, SOCt is the current state of charge of the battery system, SOCf is the initial state of charge of the battery system, ∫Idt is the current integral of the battery system within the target time, and C is the total capacity of the battery system in a fully charged state.

[0054] Calculating the state of charge differences between battery systems requires obtaining the state of charge value of each battery system and calculating the difference between the state of charge and the reference state of charge. By analyzing the causes of the differences and taking appropriate measures, the state of charge differences can be reduced and the stability and reliability of the battery system can be improved.

[0055] Step 222: Calculate the charge and discharge power that needs to be increased or decreased for each battery system based on the difference, so as to configure the balancing time, balancing speed and balancing control method of the local balancing strategy.

[0056] According to the difference in state of charge, a power adjustment factor is determined. Using the power adjustment factor and the current charge and discharge power, the charge and discharge power that needs to be increased or decreased for each battery system is calculated.

[0057] Based on the power adjustment amount and the capacity of the battery system, the equalization time required to reach the target state of charge value is calculated.

[0058] The equalization speed is the rate at which the difference in state of charge decreases. It can be controlled by adjusting the power adjustment amount.

[0059] Balancing control can be centralized or distributed. Centralized balancing usually coordinates the charging and discharging of each battery system through a central controller; distributed balancing allows each battery system to make independent charging and discharging adjustments based on its own state of charge.

[0060] Step 23: Perform active local balancing between relevant battery systems or within each battery group according to the local balancing strategy.

[0061] Active local balancing adjusts the charge and discharge power of each battery system by means of energy supplementation or transfer to achieve balance between battery systems. Energy supplementation usually involves charging a battery system with a lower state of charge through an external power source; energy transfer involves transferring part of the energy of a battery system with a higher state of charge to a battery system with a lower state of charge.

[0062] Active local balancing is performed according to the local balancing strategy, and the balancing process is ensured to be carried out within a safe range to avoid dangerous situations such as overcharging and over-discharging.

[0063] By defining goals, developing strategies, executing balancing, and evaluating and optimizing results, the consistency of the battery system can be improved, thereby extending battery life and improving the performance of the entire battery system.

[0064] Further, see Figure 4 , step 23 comprises: Step 231: Transferring energy from a battery system with a high state of charge to a battery system with a low state of charge in each battery system according to a local balancing strategy, or transferring energy from a battery group with a high state of charge to a battery group with a low state of charge in each of the battery systems.

[0065] The energy transfer balancing process is initiated, and according to the local balancing strategy, the excess energy of the high-state-of-charge battery system is transferred to the low-state-of-charge battery system through a controller or a dedicated balancing device, or the energy of the high-state-of-charge battery group in each of the battery systems is transferred to the low-state-of-charge battery group, so as to achieve local balancing within and between battery systems.

[0066] Step 232: In response to the state of charge difference between the battery systems being less than a preset difference threshold, terminate active local balancing.

[0067] Monitor the state of charge of each battery system in real time and evaluate whether the difference between them is less than a preset difference threshold.

[0068] If the difference is less than the threshold and lasts for a period of time (such as several minutes or hours, depending on system requirements and stability), the balancing process can be considered complete. When the end condition is met, the active local balancing process is stopped by the controller or dedicated balancing equipment. Ensure that all parameters related to balancing, such as current and voltage, are restored to normal.

[0069] Optionally, the end time of the balancing process, the final SOC value of each battery system, and any related abnormal or warning information are recorded, and this information is fed back to the system administrator or maintenance personnel for further analysis and optimization.

[0070] After completing the balancing, perform a reset on the battery system to ensure that all parameters are restored to their initial state. Continue to monitor the system to ensure that the consistency of the battery pack remains within acceptable ranges and be prepared to respond to any future unbalanced conditions.

[0071] Optionally, step 20 further includes updating the local balancing strategy in response to a change in the state parameter to adjust the battery system performing the state of charge transfer and the transferred energy.

[0072] Real-time monitoring of key status parameters of the battery system, such as temperature, voltage, internal resistance, etc., to assess whether these parameters exceed the preset safety range or have changed significantly. Based on the current status parameters, assess whether the local balancing strategy being executed is still valid. If it is found that the effectiveness of the strategy is reduced or may cause damage to the battery system, it needs to be updated; according to the changes in the status parameters, adjust the parameters of the balancing strategy, such as balancing current, balancing time, balancing threshold, etc.

[0073] By real-time monitoring of status parameters, evaluating strategy effectiveness, updating strategy parameters, and implementing new strategies, the consistency of the battery pack and the stability of the system can be ensured while protecting the safety of the battery system.

[0074] See also Figure 5 , Figure 5 It is a structural diagram of an embodiment of the storage medium provided by the present application.

[0075] The storage medium 300 stores program data 310. When the program data 310 is executed by the processor, the following is achieved: Figure 1 The steps of the charge and discharge control method are described.

[0076] The program data 310 is stored in a storage medium 300, and includes a number of instructions for enabling a network device (such as a router, a personal computer, a server, etc.) or a processor to execute all or part of the steps of the method described in each embodiment of the present application.

[0077] Optionally, the storage medium 300 may be a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, an optical disk, or other medium that can store program data.

[0078] See also Figure 6 , Figure 6 It is a structural schematic diagram of an embodiment of a computer device provided by the present application.

[0079] The computer device 400 includes a processor 420 and a memory 410 which are connected to each other. The memory 410 stores a computer program. When the processor 420 executes the computer program, the steps of the above-mentioned charge and discharge control method are implemented.

[0080] Different from the prior art. The present application uses a local balancing strategy to regulate the charge and discharge of the energy storage system to achieve voltage balance between battery cells. This strategy can transfer energy from single cells with higher capacity to single cells with lower capacity, thereby avoiding energy waste. The local balancing strategy can quickly identify inconsistencies in the battery pack and take corresponding balancing measures. Through precise control algorithms and efficient energy transfer mechanisms, the local balancing strategy can achieve consistency in the battery pack in a short time. By reducing the inconsistency between battery cells, the local balancing strategy can significantly improve the overall performance of the battery pack and improve the stability and life of the energy storage battery. Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the storage medium embodiment and the computer device embodiment, since they are basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0081] The present application can be used in many general or special computing system environments or configurations, such as personal computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, network PCs, minicomputers, and distributed computing environments including any of the above systems or devices.

[0082] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not performed.

[0083] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0084] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0085] The above descriptions are merely embodiments of the present application and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A charge and discharge control method for an energy storage system, characterized in that: include: Dynamically adjust the charge and discharge instructions of the energy storage system according to the used capacity of the energy storage system, the current power load and power, and the matching relationship between the power load and the energy storage system; In response to the presence of a charge and discharge instruction in which the charge and discharge power is greater than or equal to a preset threshold value, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold value to eliminate the energy difference between the battery systems related to the charge and discharge instruction.

2. The charge and discharge control method according to claim 1, characterized in that: In response to the presence of a charge and discharge instruction having a charge and discharge power greater than or equal to a preset threshold value in the charge and discharge instructions, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold value to eliminate the energy difference between the battery systems related to the charge and discharge instructions, including: In response to the presence of a charge / discharge instruction in which the charge / discharge power is greater than or equal to a preset threshold value among the charge / discharge instructions, continuously acquiring state parameters of the relevant battery systems; Generate the local balancing strategy of each of the related battery systems based on the state parameters; Active local balancing is performed between the relevant battery systems or within the relevant battery groups according to the local balancing strategy.

3. The charge and discharge control method according to claim 2, characterized in that: The generating the local balancing strategy of each of the battery systems related to the state parameter includes: Calculating the state of charge difference between the battery systems; The charge and discharge power that needs to be increased or decreased for each battery system is calculated based on the difference, so as to configure the balancing time, balancing speed and balancing control method of the local balancing strategy.

4. The charge and discharge control method according to claim 3, characterized in that: The formula for calculating the state of charge is: Among them, SOCt is the current state of charge of the battery system, SOCf is the initial state of charge of the battery system, ∫Idt is the current integral of the battery system within the target time, and C is the total capacity of the battery system in a fully charged state.

5. The charge and discharge control method according to claim 3, characterized in that: The performing active local balancing between the related battery systems according to the local balancing strategy includes: Transferring energy from the battery system with a high state of charge to the battery system with a low state of charge in each of the battery systems according to the local balancing strategy, or transferring energy from a battery group with a high state of charge to a battery group with a low state of charge in each of the battery systems; In response to the state of charge difference between the battery systems being less than a preset difference threshold, the active local balancing is terminated.

6. The charge and discharge control method according to claim 5, characterized in that: In response to the presence of a charge and discharge instruction having a charge and discharge power greater than or equal to a preset threshold value in the charge and discharge instructions, a local balancing strategy is executed on the battery system related to the charge and discharge instruction greater than or equal to the preset threshold value to eliminate the energy difference between the battery systems related to the charge and discharge instructions, and further includes: In response to the change of the state parameter, the local balancing strategy is updated to adjust the battery system for state of charge transfer and the transferred energy.

7. The charge and discharge control method according to claim 2, characterized in that: The state parameters of the battery system include: voltage, current, temperature, internal resistance, and charge and discharge state.

8. The charge and discharge control method according to claim 1, characterized in that: The dynamically adjusting the charge and discharge instructions of the energy storage system according to the used capacity of the energy storage system, the current electrical load and power, and the matching relationship between the electrical load and the energy storage system, includes: The temperature of each of the energy storage systems is monitored, and the power value of the charge and discharge instructions is adjusted according to the change of the temperature.

Images