Energy storage system and control method, device, storage medium and program product thereof

Abstract

The present invention discloses a control method, device, energy storage system, storage medium, and computer program product for an energy storage system. In the energy storage system, a liquid cooler is used to dissipate heat for a battery module. The method includes: when the battery module's control instruction is to start charging or discharging, determining an advance start time for the liquid cooler based on the battery module's set charging power or discharging power, then controlling the liquid cooler to start, and controlling the battery module to start charging or discharging after the liquid cooler's operating time reaches the advance start time; when the battery module's control instruction is to stop charging or discharging, determining an advance stop time for the liquid cooler based on the battery module's current charging power or discharging power, then controlling the liquid cooler to stop, and controlling the battery module to stop charging or discharging after the liquid cooler's downtime reaches the advance stop time. This solution can improve the accuracy of battery module temperature control, prevent condensation in the battery module, and enhance the safety of the energy storage system.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage technology, and specifically relates to a control method and device for an energy storage system, an energy storage system, a storage medium, and a computer program product. Background Art

[0002] As the power density of energy storage systems increases, most battery modules are equipped with liquid cooling plates, using coolant as a medium to quickly dissipate heat from the batteries. However, when the coolant temperature is significantly lower than the ambient temperature, condensation can easily form on the cold plate and battery module surfaces, creating electrical safety issues.

[0003] The above content is only used to assist in understanding the technical solution of the present invention and does not constitute an admission that the above content is prior art. Summary of the Invention

[0004] The object of the present invention is to provide a control method, device, energy storage system, storage medium and computer program product for an energy storage system to solve the problem of condensation easily forming on the surface of the liquid cooling plate and battery module in the energy storage system in related solutions, which may cause electrical safety. The method achieves the effect of avoiding large temperature fluctuations in the battery module by controlling the liquid cooling machine to start or stop in advance when the battery module starts charging or discharging and stops charging or discharging. At the same time, the time of early start or shutdown is determined according to the charge and discharge power, thereby improving the accuracy of temperature control, avoiding condensation in the battery module, and ensuring system safety.

[0005] The present invention provides a control method for an energy storage system, wherein the energy storage system includes a battery module and a liquid cooler; the liquid cooler is used to dissipate heat for the battery module; the method includes: obtaining a control instruction of the battery module, a set charging power or discharging power of the battery module, and a current charging power or discharging power of the battery module; when the control instruction of the battery module is an instruction to start charging or discharging the battery module, determining an advance start time of the liquid cooler according to the set charging power or discharging power of the battery module; then controlling the liquid cooler to start, and after the running time of the liquid cooler reaches the advance start time, controlling the battery module to start charging or discharging; when the control instruction of the battery module is an instruction to stop charging or discharging the battery module, determining an advance stop time of the liquid cooler according to the current charging power or discharging power of the battery module; then controlling the liquid cooler to stop, and after the stop time of the liquid cooler reaches the advance stop time, controlling the battery module to stop charging or discharging.

[0006] In some embodiments, the liquid cooler has a regulating valve; the regulating valve is used to regulate the flow rate of the coolant circulating in the liquid cooler; the method further includes: during the charging or discharging of the battery module, judging the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the first power range, controlling the opening of the regulating valve to be the first opening; if the current charging power or discharging power of the battery module is in the second power range, controlling the opening of the regulating valve to be the second opening; if the current charging power or discharging power of the battery module is in the third power range, controlling the opening of the regulating valve to be the third opening; the first power range > the second power range > the third power range, the first opening > the second opening > the third opening.

[0007] In some embodiments, the greater the set charging power or discharging power of the battery module, the longer the advance start time; and the smaller the current charging power or discharging power of the battery module, the longer the advance shutdown time.

[0008] In some embodiments, the advance start time of the liquid cooler is determined according to the set charging power or discharging power of the battery module, including: judging the size of the set charging power or discharging power of the battery module; if the set charging power or discharging power of the battery module is in the fourth power range, the advance start time of the liquid cooler is the first time; if the set charging power or discharging power of the battery module is in the fifth power range, the advance start time of the liquid cooler is the second time; if the set charging power or discharging power of the battery module is in the sixth power range, the advance start time of the liquid cooler is the third time; the fourth power range>the fifth power range>the sixth power range, the first time>the second time>the third time.

[0009] In some embodiments, the early shutdown time of the liquid cooler is determined according to the current charging power or discharging power of the battery module, including: judging the size of the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the seventh power range, the early shutdown time of the liquid cooler is the fourth time; if the current charging power or discharging power of the battery module is in the eighth power range, the early shutdown time of the liquid cooler is the fifth time; if the current charging power or discharging power of the battery module is in the ninth power range, the early shutdown time of the liquid cooler is the sixth time; the seventh power range>the eighth power range>the ninth power range, the fourth time<the fifth time<the sixth time.

[0010] In some embodiments, the control method further includes: obtaining the dew point temperature of the environment in which the battery module is located, the ambient temperature of the battery module, and the current time; after the user sets the target temperature of the liquid cooler, adjusting the target temperature so that the target temperature is between the dew point temperature and the ambient temperature; then judging whether the current time is within the first time range or the second time range; if the current time is within the first time range, reducing the first preset temperature value based on the adjusted target temperature; if the current time is within the second time range, increasing the first preset temperature value based on the adjusted target temperature.

[0011] Matching the above method, another aspect of the present invention provides a control device for an energy storage system, the energy storage system including a battery module and a liquid cooler; the liquid cooler is used to dissipate heat for the battery module; the device includes: an acquisition unit configured to acquire a control instruction of the battery module, a set charging power or discharging power of the battery module, and a current charging power or discharging power of the battery module; a control unit configured to, when the control instruction of the battery module is an instruction to start charging or discharging the battery module, determine an advance start time of the liquid cooler based on the set charging power or discharging power of the battery module; then control the liquid cooler to start, and control the battery module to start charging or discharging after the running time of the liquid cooler reaches the advance start time; the control unit is further configured to, when the control instruction of the battery module is an instruction to stop charging or discharging the battery module, determine an advance stop time of the liquid cooler based on the current charging power or discharging power of the battery module; then control the liquid cooler to stop, and control the battery module to stop charging or discharging after the stop time of the liquid cooler reaches the advance stop time.

[0012] In some embodiments, the liquid cooler has a regulating valve; the regulating valve is used to regulate the flow rate of the coolant circulating in the liquid cooler; the control unit is further configured to: during the charging or discharging process of the battery module, determine the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the first power range, control the opening of the regulating valve to be the first opening; if the current charging power or discharging power of the battery module is in the second power range, control the opening of the regulating valve to be the second opening; if the current charging power or discharging power of the battery module is in the third power range, control the opening of the regulating valve to be the third opening; the first power range > the second power range > the third power range, the first opening > the second opening > the third opening.

[0013] In some embodiments, the greater the set charging power or discharging power of the battery module, the longer the advance start time; and the smaller the current charging power or discharging power of the battery module, the longer the advance shutdown time.

[0014] In some embodiments, the control unit determines the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module, including: judging the size of the set charging power or discharging power of the battery module; if the set charging power or discharging power of the battery module is in the fourth power range, the advance start time of the liquid cooler is the first time; if the set charging power or discharging power of the battery module is in the fifth power range, the advance start time of the liquid cooler is the second time; if the set charging power or discharging power of the battery module is in the sixth power range, the advance start time of the liquid cooler is the third time; the fourth power range>the fifth power range>the sixth power range, the first time>the second time>the third time.

[0015] In some embodiments, the control unit determines the early shutdown time of the liquid cooler based on the current charging power or discharging power of the battery module, including: judging the size of the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the seventh power range, the early shutdown time of the liquid cooler is the fourth time; if the current charging power or discharging power of the battery module is in the eighth power range, the early shutdown time of the liquid cooler is the fifth time; if the current charging power or discharging power of the battery module is in the ninth power range, the early shutdown time of the liquid cooler is the sixth time; the seventh power range>the eighth power range>the ninth power range, the fourth time<the fifth time<the sixth time.

[0016] In some embodiments, the acquisition unit is further configured to acquire the dew point temperature of the environment in which the battery module is located, the ambient temperature of the battery module, and the current time; the control unit is further configured to adjust the target temperature after the user sets the target temperature of the liquid cooler, so that the target temperature is between the dew point temperature and the ambient temperature; and then determine whether the current time is within the first time range or the second time range; the control unit is further configured to reduce the first preset temperature value based on the adjusted target temperature if the current time is within the first time range; the control unit is further configured to increase the first preset temperature value based on the adjusted target temperature if the current time is within the second time range.

[0017] In accordance with the above-mentioned device, the present invention further provides an energy storage system, comprising: the control device of the energy storage system described above.

[0018] In accordance with the above method, the present invention further provides a storage medium, which includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the above-mentioned energy storage system control method.

[0019] In accordance with the above method, the present invention further provides a computer program product, which includes a computer program. When the computer program product is processed and executed, the steps of the above method for controlling the energy storage system are implemented.

[0020] The solution of the present invention determines the advance start time of the liquid cooler based on the battery module's set charge or discharge power when the battery module's control instruction initiates charging or discharging. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction initiates charging or discharging, the advance stop time of the liquid cooler is determined based on the battery module's current charge or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. By controlling the liquid cooler to start or stop early when the battery module starts or stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge or discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0021] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention.

[0022] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic flow chart of an embodiment of a method for controlling an energy storage system according to the present invention;

[0024] Figure 2 1. A schematic flow chart of an embodiment of the method for correcting the target temperature of a liquid cooler in the present invention;

[0025] Figure 3 Schematic diagram of the structure of an embodiment of a control device for an energy storage system of the present invention.

[0026] In conjunction with the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0027] 102 - acquisition unit; 104 - control unit. DETAILED DESCRIPTION

[0028] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] In order to prevent condensation from occurring at the battery modules in the energy storage system, relevant solutions measure the temperature and humidity of the environment inside the battery module compartment, calculate the dew point temperature, and use this as a regulation signal to dynamically adjust the coolant supply temperature to be higher than the dew point temperature. Some solutions also install dehumidifiers in the battery module compartment and set the dehumidification start humidity value or temperature value to reduce the humidity value in the battery compartment environment. Although these solutions can solve the problem of condensation during the operation of the energy storage system, they do not consider the condensation that may be caused by the slow shutdown process of the liquid cooler after the energy storage system is shut down. In addition, the liquid coolers of the energy storage battery modules are all controlled by external or internal temperature commands, and the power flow of the energy storage system or the photovoltaic storage direct flexible energy station system is not considered. The temperature regulation often lags behind the regulation of the energy storage charging and discharging power, resulting in large temperature fluctuations and frequent adjustments.

[0030] Therefore, this solution controls the liquid cooler to start or stop in advance before the battery is charged or discharged, and when the battery is about to stop charging or discharging, to avoid large temperature fluctuations at the battery. At the same time, the start or stop time is determined according to the battery charge and discharge power, and the battery temperature is precisely controlled to prevent condensation caused by excessively low battery temperature, which can avoid electrical short circuits caused by condensation and ensure system safety.

[0031] According to an embodiment of the present invention, a control method for an energy storage system is provided. The energy storage system includes a battery module and a liquid cooler; the liquid cooler is used to dissipate heat from the battery module. The battery module is mounted on a cold plate in the energy storage system. After the liquid cooler is turned on, the liquid cooler supplies coolant to the cold plate, thereby transferring the cold energy through the cold plate to the battery module, dissipating heat from the battery module. During this process, the starting temperature drop point is at the bottom of the battery module, and the temperature sampling point of the battery module is at the battery tab (the top of the battery). Due to thermal resistance, if the cooling effect of the liquid cooler is too strong, the battery module will experience large temperature fluctuations throughout the entire operation process; if the cooling effect of the liquid cooler is not strong enough, the battery module will not be effectively cooled. Therefore, this solution implements pre-regulation of the liquid cooler before and after the energy storage system is shut down based on the battery module's charge and discharge strategy, avoiding condensation and large temperature fluctuations at the battery module and improving the accuracy of temperature control.

[0032] like Figure 1 FIG2 is a flow chart of an embodiment of the method of the present invention. The energy storage system control method may include: steps S110 to S130.

[0033] In step S110 , a control instruction of the battery module, a set charging power or discharging power of the battery module, and a current charging power or discharging power of the battery module are acquired.

[0034] The user issues control commands to the system to start or stop charging or discharging the battery module. These commands include a start charge / discharge command and a stop charge / discharge command. When setting the battery module to start charging or discharging, the user also sets the charge / discharge power and time. This means the user sets the battery module to charge or discharge at a certain power level within a certain timeframe. While the battery module is charging or discharging, if the user manually stops charging or discharging, or if charging or discharging ends after the set time, the system will receive a stop charge or discharge command. When the control command is to start charging or discharging, the system will obtain the charge / discharge power set by the user; when the control command is to stop charging or discharging, the system will obtain the current charge / discharge power of the battery module. The system will then control the liquid cooler to start or stop early based on the obtained charge / discharge power.

[0035] At step S120, when the control instruction of the battery module is an instruction to start charging or discharging the battery module, the advance start time of the liquid cooler is determined according to the set charging power or discharging power of the battery module; then the liquid cooler is controlled to start, and after the operating time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging.

[0036] Before the battery modules charge or discharge, the liquid cooler is controlled to start in advance, cooling the battery modules in advance. Once charging and discharging begins, the cooling energy can be quickly and fully dissipated from the battery modules, avoiding temperature lag caused by inconsistent temperatures at the top and bottom of the battery modules due to thermal resistance, thus preventing large temperature fluctuations in the battery modules. The liquid cooler's start-up time is also controlled according to the set charge and discharge power of the battery modules to prevent condensation and ensure system safety.

[0037] In some embodiments, the greater the set charging power or discharging power of the battery module, the longer the advance start time.

[0038] If the set charge and discharge power is larger, the heat generated by the battery module after the start of charge and discharge will be greater, and the temperature change will be more obvious. At this time, more cooling capacity is required to reduce the temperature of the battery module to a normal value. Therefore, when the set charge and discharge power is larger, the liquid cooler will start up longer in advance, so that the liquid cooler can provide more cooling capacity for the battery module in advance, thereby preventing the battery module temperature from rising significantly after the start of charge and discharge.

[0039] In some embodiments, in step S120, the specific process of determining the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module includes: judging the size of the set charging power or discharging power of the battery module; if the set charging power or discharging power of the battery module is in the fourth power range, the advance start time of the liquid cooler is the first time; if the set charging power or discharging power of the battery module is in the fifth power range, the advance start time of the liquid cooler is the second time; if the set charging power or discharging power of the battery module is in the sixth power range, the advance start time of the liquid cooler is the third time; the fourth power range>the fifth power range>the sixth power range, the first time>the second time>the third time.

[0040] When determining the advance start time of the liquid cooler based on the set charge and discharge power of the battery module, the corresponding advance start time can be set according to the range of the set charge and discharge power, so that the greater the set charge and discharge power, the greater the advance start time, so as to prevent the liquid cooler from starting too short a time in advance, causing large fluctuations in the battery module temperature.

[0041] Optionally, a linear relationship can be established between the set charge / discharge power and the advance start time, in which the set charge / discharge power and the advance start time are directly proportional, for example, advance start time = k1 * set charge / discharge power, where k1 is a coefficient greater than 0. The corresponding advance start time can then be determined based on the user-set charge / discharge power and this linear relationship.

[0042] At step S130, when the control instruction of the battery module is an instruction to stop charging or discharging the battery module, the advance shutdown time of the liquid cooler is determined according to the current charging power or discharging power of the battery module; then the liquid cooler is controlled to stop, and after the shutdown time of the liquid cooler reaches the advance shutdown time, the battery module is controlled to stop charging or discharging.

[0043] Because the compressor in the liquid cooler takes time to fully stop when the battery module is shut down, the cooler will continue to operate for a period of time when both the battery module and the cooler are shut down simultaneously. During this period, the battery module generates no heat, causing the module temperature to drop significantly, making condensation more likely to form. Therefore, the cooler is controlled to stop prematurely when the battery module is about to stop charging or discharging to prevent condensation. The timing of the premature cooler stop is also controlled based on the battery module's charge and discharge power to ensure that the battery module temperature does not rise significantly after the cooler stops, thereby affecting battery performance.

[0044] In some embodiments, the smaller the current charging power or discharging power of the battery module is, the longer the early shutdown time is.

[0045] The greater the charge and discharge power of the battery module, the greater the heat generated by the battery. Therefore, it is necessary to shorten the early shutdown time of the liquid cooler to prevent the battery module from heating up too high after the liquid cooler stops early. That is, the early shutdown time of the liquid cooler is inversely proportional to the current charge and discharge power.

[0046] In some embodiments, in step S130, the specific process of determining the advance shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module includes: judging the size of the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the seventh power range, the advance shutdown time of the liquid cooler is the fourth time; if the current charging power or discharging power of the battery module is in the eighth power range, the advance shutdown time of the liquid cooler is the fifth time; if the current charging power or discharging power of the battery module is in the ninth power range, the advance shutdown time of the liquid cooler is the sixth time; the seventh power range>the eighth power range>the ninth power range, the fourth time<the fifth time<the sixth time.

[0047] When determining the early shutdown time of the liquid cooler based on the current charge and discharge power of the battery module, the corresponding early shutdown time can be set according to the range of the current charge and discharge power, so that the greater the current charge and discharge power, the longer the early shutdown time, so as to prevent the liquid cooler from stopping too long in advance, causing large fluctuations in the temperature of the battery module.

[0048] Optionally, a linear relationship can be established between the current charge / discharge power and the early shutdown time, where the current charge / discharge power and the early shutdown time are inversely proportional. For example, early shutdown time = k2 * current charge / discharge power, where k2 is a coefficient less than 0. The corresponding early shutdown time can then be determined based on the current charge / discharge power and this linear relationship.

[0049] In some embodiments, the liquid cooler includes a regulating valve configured to regulate the flow of coolant circulating in the liquid cooler. The control method further includes regulating the flow of coolant during charging or discharging of the battery module, the process specifically comprising: determining the current charging power or discharging power of the battery module during charging or discharging; if the current charging power or discharging power of the battery module is within a first power range, controlling the opening of the regulating valve to a first opening; if the current charging power or discharging power of the battery module is within a second power range, controlling the opening of the regulating valve to a second opening; if the current charging power or discharging power of the battery module is within a third power range, controlling the opening of the regulating valve to a third opening; the first power range > the second power range > the third power range, and the first opening > the second opening > the third opening.

[0050] As battery modules charge and discharge, the charge and discharge power may vary, causing the module's heat generation to vary. To ensure that the cooling capacity provided by the liquid cooler matches the module's heat generation and maintains the module's temperature within a set range, the opening of the regulating valve is controlled in real time based on the charge and discharge power, adjusting the coolant flow rate. This prevents condensation from occurring when the battery module's temperature is too low, and prevents excessively high temperatures from degrading battery performance and safety. The charge and discharge power is directly proportional to the regulating valve opening. The greater the charge and discharge power, the wider the regulating valve opening, the greater the coolant flow rate, the greater the cooling capacity provided, and the improved cooling effect on the battery module.

[0051] In some embodiments, the control method further includes a process of adjusting the target temperature of the liquid cooler, such as Figure 2 As shown, the process specifically includes: step S210 to step S240.

[0052] Step S210 , obtaining the dew point temperature of the environment in which the battery module is located, the ambient temperature of the battery module, and the current time.

[0053] Step S220, after the user sets the target temperature of the liquid cooler, adjust the target temperature so that the target temperature is between the dew point temperature and the ambient temperature; then determine whether the current time is within the first time range or the second time range.

[0054] Step S230: If the current time is within the first time range, it is considered that it is daytime, and the first preset temperature value is reduced based on the adjusted target temperature.

[0055] Step S240: If the current time is within the second time range, it is considered that it is night, and the first preset temperature value is increased based on the adjusted target temperature.

[0056] When the system is running, the user will set the target temperature of the liquid cooler, and then the system will correct the target temperature to make it more suitable for the current environment and working conditions.

[0057] The target temperature correction is based on the battery module's ambient temperature and the ambient dew point. If the target temperature exceeds the ambient temperature, the battery module will not be effectively cooled. If the target temperature is below the dew point, condensation will form on the battery module. Therefore, the target temperature is corrected to be between the dew point and the ambient temperature.

[0058] The target temperature correction also factors in the current time, which is used to determine whether it is daytime or nighttime. When the user sets the battery module's charge and discharge strategy to photovoltaic self-consumption, the battery module charges during the day and not at night. Therefore, the battery module generates higher heat during the day and lower heat at night. For example, the table below shows a comparison of the highest and lowest battery cell temperatures. The temperature difference is greater during daytime discharge than during nighttime discharge. The daytime period is 13:40-15:08, while the nighttime period is 18:30-19:45.

[0059]

[0060] Therefore, the target temperature can be further adjusted based on the different heat generation of the battery modules during the day and at night. The first time range corresponds to the daytime period, for example, 9:00-17:00, and the second time range corresponds to the nighttime period, for example, 18:00-6:00. If it is daytime and the battery modules generate more heat, the target temperature of the liquid cooler can be appropriately lowered to improve the cooling effect. If it is nighttime and the battery modules generate less heat, the target temperature of the liquid cooler can be appropriately raised to prevent condensation on the battery modules. The first preset temperature value can be set to 0.5°C.

[0061] Optionally, during the daytime, the solar radiation intensity varies at different times, resulting in different battery module charging power and heat generation. Therefore, the first time range can be divided more finely, and the corresponding target temperature adjustment amount can also be different. For example, if the current time is 11:00-14:00, the battery module charging power is high, and the target temperature can be reduced by 1°C; if the current time is 14:00-17:00, the battery module charging power is low, and the target temperature can be reduced by 0.5°C.

[0062] Using the technical solution of this embodiment, when the battery module's control instruction is to start charging or discharging the battery module, the liquid cooler's advance start time is determined based on the battery module's set charge power or discharge power. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction is to stop charging or discharging the battery module, the liquid cooler's advance stop time is determined based on the battery module's current charge power or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. Thus, by controlling the liquid cooler to start or stop in advance when the battery module starts and stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge and discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0063] According to an embodiment of the present invention, a control device for an energy storage system corresponding to the control method of an energy storage system is also provided. The energy storage system includes a battery module and a liquid cooler; the liquid cooler is used to dissipate heat for the battery module. The battery module is arranged on a cold plate in the energy storage system. After the liquid cooler is turned on, the liquid cooler supplies coolant to the cold plate, thereby transferring the cold energy through the cold plate to the battery module to dissipate heat for the battery module. During this process, the starting point for cooling is at the bottom of the battery module, and the temperature sampling point of the battery module is at the battery tab (the top of the battery). Due to the presence of thermal resistance, if the cooling effect of the liquid cooler is too strong, it will cause the battery module to have large temperature fluctuations during the entire operation process; if the cooling effect of the liquid cooler is not strong enough, the battery module will not be effectively cooled. Therefore, this solution realizes pre-regulation of the liquid cooler before and after the energy storage system is shut down according to the charging and discharging strategy of the battery module, thereby avoiding condensation and large temperature fluctuations at the battery module and improving the accuracy of temperature control.

[0064] See also Figure 3 The control device of the energy storage system may include: an acquisition unit 102 and a control unit 104 .

[0065] The acquisition unit 102 is configured to acquire the control instruction of the battery module, the set charging power or discharging power of the battery module, and the current charging power or discharging power of the battery module. The specific functions and processing of the acquisition unit 102 are shown in step S110.

[0066] The user issues control commands to the system to start or stop charging or discharging the battery module. These commands include a start charge / discharge command and a stop charge / discharge command. When setting the battery module to start charging or discharging, the user also sets the charge / discharge power and time. This means the user sets the battery module to charge or discharge at a certain power level within a certain timeframe. While the battery module is charging or discharging, if the user manually stops charging or discharging, or if charging or discharging ends after the set time, the system will receive a stop charge or discharge command. When the control command is to start charging or discharging, the system will obtain the charge / discharge power set by the user; when the control command is to stop charging or discharging, the system will obtain the current charge / discharge power of the battery module. The system will then control the liquid cooler to start or stop early based on the obtained charge / discharge power.

[0067] The control unit 104 is configured to, when the control instruction for the battery module is to start charging or discharging the battery module, determine an advance start time for the liquid cooler based on the set charging power or discharging power of the battery module; thereafter control the liquid cooler to start, and control the battery module to start charging or discharging after the liquid cooler's operating time reaches the advance start time. The specific functions and processing of the control unit 104 are described in step S120.

[0068] Before the battery modules charge or discharge, the liquid cooler is controlled to start in advance, cooling the battery modules in advance. Once charging and discharging begins, the cooling energy can be quickly and fully dissipated from the battery modules, avoiding temperature lag caused by inconsistent temperatures at the top and bottom of the battery modules due to thermal resistance, thus preventing large temperature fluctuations in the battery modules. The liquid cooler's start-up time is also controlled according to the set charge and discharge power of the battery modules to prevent condensation and ensure system safety.

[0069] In some embodiments, the greater the set charging power or discharging power of the battery module, the longer the advance start time.

[0070] If the set charge and discharge power is larger, the heat generated by the battery module after the start of charge and discharge will be greater, and the temperature change will be more obvious. At this time, more cooling capacity is required to reduce the temperature of the battery module to a normal value. Therefore, when the set charge and discharge power is larger, the liquid cooler will start up longer in advance, so that the liquid cooler can provide more cooling capacity for the battery module in advance, thereby preventing the battery module temperature from rising significantly after the start of charge and discharge.

[0071] In some embodiments, the control unit 104 determines the specific process of the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module, including: judging the size of the set charging power or discharging power of the battery module; if the set charging power or discharging power of the battery module is in the fourth power range, the advance start time of the liquid cooler is the first time; if the set charging power or discharging power of the battery module is in the fifth power range, the advance start time of the liquid cooler is the second time; if the set charging power or discharging power of the battery module is in the sixth power range, the advance start time of the liquid cooler is the third time; the fourth power range>the fifth power range>the sixth power range, the first time>the second time>the third time.

[0072] When determining the advance start time of the liquid cooler based on the set charge and discharge power of the battery module, the corresponding advance start time can be set according to the range of the set charge and discharge power, so that the greater the set charge and discharge power, the greater the advance start time, so as to prevent the liquid cooler from starting too short a time in advance, causing large fluctuations in the battery module temperature.

[0073] Optionally, a linear relationship can be established between the set charge / discharge power and the advance start time, in which the set charge / discharge power and the advance start time are directly proportional, for example, advance start time = k1 * set charge / discharge power, where k1 is a coefficient greater than 0. The corresponding advance start time can then be determined based on the user-set charge / discharge power and this linear relationship.

[0074] The control unit 104 is further configured to, when the control instruction for the battery module is to stop charging or discharging the battery module, determine an advanced shutdown time for the liquid cooler based on the current charging power or discharging power of the battery module; thereafter control the liquid cooler to shut down, and control the battery module to stop charging or discharging after the shutdown time of the liquid cooler reaches the advanced shutdown time. The specific functions and processing of the control unit 104 are described in step S130.

[0075] Because the compressor in the liquid cooler takes time to fully stop when the battery module is shut down, the cooler will continue to operate for a period of time when both the battery module and the cooler are shut down simultaneously. During this period, the battery module generates no heat, causing the module temperature to drop significantly, making condensation more likely to form. Therefore, the cooler is controlled to stop prematurely when the battery module is about to stop charging or discharging to prevent condensation. The timing of the premature cooler stop is also controlled based on the battery module's charge and discharge power to ensure that the battery module temperature does not rise significantly after the cooler stops, thereby affecting battery performance.

[0076] In some embodiments, the smaller the current charging power or discharging power of the battery module is, the longer the early shutdown time is.

[0077] The greater the charge and discharge power of the battery module, the greater the heat generated by the battery. Therefore, it is necessary to shorten the early shutdown time of the liquid cooler to prevent the battery module from heating up too high after the liquid cooler stops early. That is, the early shutdown time of the liquid cooler is inversely proportional to the current charge and discharge power.

[0078] In some embodiments, the control unit 104 determines the specific process of the early shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module, including: judging the size of the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is in the seventh power range, the early shutdown time of the liquid cooler is the fourth time; if the current charging power or discharging power of the battery module is in the eighth power range, the early shutdown time of the liquid cooler is the fifth time; if the current charging power or discharging power of the battery module is in the ninth power range, the early shutdown time of the liquid cooler is the sixth time; the seventh power range>the eighth power range>the ninth power range, the fourth time<the fifth time<the sixth time.

[0079] When determining the early shutdown time of the liquid cooler based on the current charge and discharge power of the battery module, the corresponding early shutdown time can be set according to the range of the current charge and discharge power, so that the greater the current charge and discharge power, the longer the early shutdown time, so as to prevent the liquid cooler from stopping too long in advance, causing large fluctuations in the temperature of the battery module.

[0080] Optionally, a linear relationship can be established between the current charge / discharge power and the early shutdown time, where the current charge / discharge power and the early shutdown time are inversely proportional. For example, early shutdown time = k2 * current charge / discharge power, where k2 is a coefficient less than 0. The corresponding early shutdown time can then be determined based on the current charge / discharge power and this linear relationship.

[0081] In some embodiments, the liquid cooler has a regulating valve; the regulating valve is used to adjust the flow rate of the coolant circulating in the liquid cooler. The control unit 104 is further configured to: during the charging or discharging process of the battery module, determine the current charging power or discharging power of the battery module; if the current charging power or discharging power of the battery module is within a first power range, control the opening of the regulating valve to a first opening; if the current charging power or discharging power of the battery module is within a second power range, control the opening of the regulating valve to a second opening; if the current charging power or discharging power of the battery module is within a third power range, control the opening of the regulating valve to a third opening; the first power range > the second power range > the third power range, and the first opening > the second opening > the third opening.

[0082] As battery modules charge and discharge, the charge and discharge power may vary, causing the module's heat generation to vary. To ensure that the cooling capacity provided by the liquid cooler matches the module's heat generation and maintains the module's temperature within a set range, the opening of the regulating valve is controlled in real time based on the charge and discharge power, adjusting the coolant flow rate. This prevents condensation from occurring when the battery module's temperature is too low, and prevents excessively high temperatures from degrading battery performance and safety. The charge and discharge power is directly proportional to the regulating valve opening. The greater the charge and discharge power, the wider the regulating valve opening, the greater the coolant flow rate, the greater the cooling capacity provided, and the improved cooling effect on the battery module.

[0083] In some embodiments, the control device comprises:

[0084] The acquisition unit 102 is further configured to acquire the dew point temperature of the environment in which the battery module is located, the ambient temperature of the battery module, and the current time. Specific functions and processing of the acquisition unit 102 are described in step S210.

[0085] The control unit 104 is further configured to, after the user sets a target temperature for the liquid cooler, adjust the target temperature so that the target temperature is between the dew point temperature and the ambient temperature; and then determine whether the current time is within the first time range or the second time range. The specific functions and processing of the control unit 104 are described in step S220.

[0086] The control unit 104 is further configured to, if the current time is within the first time range and it is considered to be daytime, reduce the first preset temperature value based on the adjusted target temperature. The specific functions and processing of the control unit 104 are shown in step S230.

[0087] The control unit 104 is further configured to, if the current time is within the second time range, determine that it is night, and then increase the first preset temperature value based on the adjusted target temperature. The specific functions and processing of the control unit 104 are shown in step S240.

[0088] When the system is running, the user will set the target temperature of the liquid cooler, and then the system will correct the target temperature to make it more suitable for the current environment and working conditions.

[0089] The target temperature correction is based on the battery module's ambient temperature and the ambient dew point. If the target temperature exceeds the ambient temperature, the battery module will not be effectively cooled. If the target temperature is below the dew point, condensation will form on the battery module. Therefore, the target temperature is corrected to be between the dew point and the ambient temperature.

[0090] The target temperature correction also factors in the current time, which is used to determine whether it is daytime or nighttime. When the user sets the battery module's charge and discharge strategy to photovoltaic self-consumption, the battery module charges during the day and not at night. Therefore, the battery module generates higher heat during the day and lower heat at night. For example, the table below shows a comparison of the highest and lowest battery cell temperatures. The temperature difference is greater during daytime discharge than during nighttime discharge. The daytime period is 13:40-15:08, while the nighttime period is 18:30-19:45.

[0091]

[0092]

[0093] Therefore, the target temperature can be further adjusted based on the different heat generation of the battery modules during the day and at night. The first time range corresponds to the daytime period, for example, 9:00-17:00, and the second time range corresponds to the nighttime period, for example, 18:00-6:00. If it is daytime and the battery modules generate more heat, the target temperature of the liquid cooler can be appropriately lowered to improve the cooling effect. If it is nighttime and the battery modules generate less heat, the target temperature of the liquid cooler can be appropriately raised to prevent condensation on the battery modules. The first preset temperature value can be set to 0.5°C.

[0094] Optionally, during the daytime, the solar radiation intensity varies at different times, resulting in different battery module charging power and heat generation. Therefore, the first time range can be divided more finely, and the corresponding target temperature adjustment amount can also be different. For example, if the current time is 11:00-14:00, the battery module charging power is high, and the target temperature can be reduced by 1°C; if the current time is 14:00-17:00, the battery module charging power is low, and the target temperature can be reduced by 0.5°C.

[0095] Since the processing and functions implemented by the device of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for any details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0096] According to the technical solution of the present invention, when the battery module's control instruction is to start charging or discharging the battery module, the liquid cooler's advance start time is determined based on the battery module's set charge power or discharge power. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction is to stop charging or discharging the battery module, the liquid cooler's advance stop time is determined based on the battery module's current charge power or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. By controlling the liquid cooler to start or stop in advance when the battery module starts or stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge and discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0097] According to an embodiment of the present invention, an energy storage system corresponding to the control device of the energy storage system is also provided. The energy storage system may include: the control device of the energy storage system described above.

[0098] Since the processing and functions implemented by the energy storage system of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned devices, for any details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0099] According to the technical solution of the present invention, when the battery module's control instruction is to start charging or discharging the battery module, the liquid cooler's advance start time is determined based on the battery module's set charge power or discharge power. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction is to stop charging or discharging the battery module, the liquid cooler's advance stop time is determined based on the battery module's current charge power or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. By controlling the liquid cooler to start or stop in advance when the battery module starts or stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge and discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0100] According to an embodiment of the present invention, a storage medium corresponding to the control method of the energy storage system is also provided, wherein the storage medium includes a stored program, wherein when the program is run, the device where the storage medium is located is controlled to execute the control method of the energy storage system described above.

[0101] Since the processing and functions implemented by the storage medium of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for any details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0102] According to the technical solution of the present invention, when the battery module's control instruction is to start charging or discharging the battery module, the liquid cooler's advance start time is determined based on the battery module's set charge power or discharge power. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction is to stop charging or discharging the battery module, the liquid cooler's advance stop time is determined based on the battery module's current charge power or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. By controlling the liquid cooler to start or stop in advance when the battery module starts or stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge and discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0103] According to an embodiment of the present invention, a computer program product corresponding to the energy storage system control method is also provided. The computer program product includes a computer program. When the computer program product is processed and executed, the steps of the energy storage system control method are implemented.

[0104] Since the processing and functions implemented by the computer program product of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for any details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0105] According to the technical solution of the present invention, when the battery module's control instruction is to start charging or discharging the battery module, the liquid cooler's advance start time is determined based on the battery module's set charge power or discharge power. The liquid cooler is then controlled to start, and after the liquid cooler's operating time reaches the advance start time, the battery module is controlled to start charging or discharging. When the battery module's control instruction is to stop charging or discharging the battery module, the liquid cooler's advance stop time is determined based on the battery module's current charge power or discharge power. The liquid cooler is then controlled to stop, and after the liquid cooler's downtime reaches the advance stop time, the battery module is controlled to stop charging or discharging. By controlling the liquid cooler to start or stop in advance when the battery module starts or stops charging or discharging, large temperature fluctuations in the battery module are avoided. Furthermore, by determining the advance start or stop time based on the charge and discharge power, the accuracy of temperature control is improved, condensation in the battery module is avoided, and system safety is ensured.

[0106] In summary, it is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0107] The foregoing description is merely an embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of the claims.

Claims

1. A control method for an energy storage system, characterized in that: The energy storage system includes a battery module and a liquid cooler; the liquid cooler is used to dissipate heat for the battery module; the method includes: Obtaining a control instruction of the battery module, a set charging power or discharging power of the battery module, and a current charging power or discharging power of the battery module; When the control instruction of the battery module is an instruction to start charging or discharging the battery module, determining an advance start time of the liquid cooler according to the set charging power or discharging power of the battery module; then controlling the liquid cooler to start, and after the operating time of the liquid cooler reaches the advance start time, controlling the battery module to start charging or discharging; When the control instruction of the battery module is an instruction to stop charging or discharging the battery module, the advance shutdown time of the liquid cooler is determined according to the current charging power or discharging power of the battery module; then the liquid cooler is controlled to stop, and after the shutdown time of the liquid cooler reaches the advance shutdown time, the battery module is controlled to stop charging or discharging.

2. The control method of the energy storage system according to claim 1, characterized in that: The liquid cooler has a regulating valve; the regulating valve is used to adjust the flow rate of the coolant circulating in the liquid cooler; The method further comprises: During the charging or discharging process of the battery module, determining the current charging power or discharging power of the battery module; If the current charging power or discharging power of the battery module is within a first power range, controlling the opening of the regulating valve to be a first opening; If the current charging power or discharging power of the battery module is within a second power range, controlling the opening of the regulating valve to be a second opening; If the current charging power or discharging power of the battery module is in the third power range, the opening of the regulating valve is controlled to be the third opening; the first power range>the second power range>the third power range, the first opening>the second opening>the third opening.

3. The control method of the energy storage system according to claim 1, characterized in that: The greater the set charging power or discharging power of the battery module, the longer the advance start time; and the smaller the current charging power or discharging power of the battery module, the longer the advance shutdown time.

4. The control method of the energy storage system according to claim 1 or 3, characterized in that: Determining the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module includes: Determining the size of the set charging power or discharging power of the battery module; If the set charging power or discharging power of the battery module is within a fourth power range, the advance start time of the liquid cooler is the first time; If the set charging power or discharging power of the battery module is within the fifth power range, the advance start time of the liquid cooler is the second time; If the set charging power or discharging power of the battery module is in the sixth power range, the advance start time of the liquid cooler is the third time; the fourth power range>the fifth power range>the sixth power range, the first time>the second time>the third time.

5. The control method of the energy storage system according to claim 1 or 3, characterized in that: Determining the early shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module includes: Determining the current charging power or discharging power of the battery module; If the current charging power or discharging power of the battery module is within the seventh power range, the early shutdown time of the liquid cooler is the fourth time; If the current charging power or discharging power of the battery module is within the eighth power range, the early shutdown time of the liquid cooler is the fifth time; If the current charging power or discharging power of the battery module is in the ninth power range, the early shutdown time of the liquid cooler is the sixth time; the seventh power range>the eighth power range>the ninth power range, and the fourth time<the fifth time<the sixth time.

6. The control method of the energy storage system according to any one of claims 1 to 3, characterized in that: Also includes: Obtaining the dew point temperature of the environment in which the battery module is located, the ambient temperature of the battery module, and the current time; After the user sets the target temperature of the liquid cooler, the target temperature is adjusted so that the target temperature is between the dew point temperature and the ambient temperature; and then, it is determined whether the current time is within the first time range or the second time range; If the current time is within the first time range, reducing the first preset temperature value based on the adjusted target temperature; If the current time is within the second time range, the first preset temperature value is increased based on the adjusted target temperature.

7. A control device for an energy storage system, characterized in that: The energy storage system includes a battery module and a liquid cooler; the liquid cooler is used to dissipate heat for the battery module; the device includes: an acquiring unit, configured to acquire a control instruction of the battery module, a set charging power or discharging power of the battery module, and a current charging power or discharging power of the battery module; a control unit configured to, when the control instruction of the battery module is an instruction to start charging or discharging the battery module, determine an advance start time of the liquid cooler according to a set charging power or discharging power of the battery module; thereafter control the liquid cooler to start, and control the battery module to start charging or discharging after the operating time of the liquid cooler reaches the advance start time; The control unit is further configured to determine the advance shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module when the control instruction of the battery module is an instruction to stop charging or discharging the battery module; then control the liquid cooler to stop, and after the shutdown time of the liquid cooler reaches the advance shutdown time, control the battery module to stop charging or discharging.

8. An energy storage system, characterized in that: include: The control device for the energy storage system according to claim 7.

9. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is executed, the device where the storage medium is located is controlled to execute the energy storage system control method according to any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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