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

Abstract

The invention discloses a control method and device of an energy storage system, the energy storage system, a storage medium and a computer program product. A liquid cooling machine in the energy storage system is used for cooling a battery module; the method comprises the following steps: when a control instruction of a battery module is to start charging or discharging, determining the advanced starting time of the liquid cooling machine according to the set charging power or discharging power of the battery module, then controlling the liquid cooling machine to start, and after the running time of the liquid cooling machine reaches the advanced starting time, controlling the battery module to start charging or discharging; and when the control instruction of the battery module is to stop charging or discharging, the advanced shutdown time of the liquid cooling machine is determined according to the current charging power or discharging power of the battery module, then the liquid cooling machine is controlled to stop, and after the shutdown time of the liquid cooling machine reaches the advanced shutdown time, the battery module is controlled to stop charging or discharging. According to the scheme, the accuracy of temperature control of the battery module can be improved, condensation of the battery module is avoided, and the safety of the energy storage system is improved.

Description

Technical Field

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

[0002] As the power density of energy storage systems increases, most energy storage system battery modules choose to install liquid cooling plates to quickly dissipate heat from the batteries using coolant. However, when the coolant temperature is much lower than the ambient temperature, condensation is likely to occur on the surface of the liquid cooling plate and battery modules, causing electrical safety issues.

[0003] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are 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, so as to solve the problem that condensation is easily generated on the surface of the liquid cooling plate and the battery module in the energy storage system in the related scheme, which causes electrical safety. The liquid cooling machine is controlled to start or stop in advance when the battery module starts to charge and discharge and stops charging and discharging, so as to avoid large temperature fluctuations in the battery module. At the same time, the time of early start or shutdown is determined according to the charge and discharge power, so as to improve the accuracy of temperature control, avoid condensation in the battery module, and ensure the safety of the system.

[0005] The present invention provides a control method for an energy storage system, the energy storage system comprises a battery module and a liquid cooler; the liquid cooler is used for dissipating heat for the battery module; the method comprises: 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 for starting charging or discharging of 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 for stopping charging or discharging of 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 adjust the flow rate of the coolant circulating in the liquid cooler; the method also includes: during the charging or discharging process 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 advance shutdown time of the liquid cooler is determined according to the current charging power or discharging power of the battery module, including: judging according to 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.

[0010] In some embodiments, the control method 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, 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, the present invention provides a control device for an energy storage system on the other hand, 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 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 determine the advance start time of the liquid cooler according to the set 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; 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 also configured to determine the advance stop 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 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 adjust the flow rate of the coolant circulating in the liquid cooler; the control unit is also 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 advance shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module, including: judging according to 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.

[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] Matching the above device, the present invention further provides an energy storage system on the other hand, including: the control device of the energy storage system described above.

[0018] In accordance with the above method, the present invention provides a storage medium on another aspect, wherein 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 above-mentioned method for controlling the energy storage system.

[0019] In accordance with the above method, the present invention provides a computer program product on another aspect. The computer program product includes a computer program. When the computer program product is processed and executed, the steps of the above energy storage system control method are implemented.

[0020] The scheme of the present invention, when the control instruction of the battery module is for the battery module to start charging or discharging, the advance start time of the liquid cooler is determined according to the set charging power or discharging power of the battery module, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is for the battery module to stop charging or discharging, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 apparent 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 diagram of a flow chart of an embodiment of a method for controlling an energy storage system of the present invention;

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

[0025] Figure 3 It is a structural schematic diagram 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] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work 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 in the battery module compartment, calculate the dew point temperature, and use this as a regulation signal to dynamically adjust the coolant supply temperature to make it higher than the dew point temperature. Some solutions also reduce the humidity value in the battery compartment environment by installing a dehumidifier in the battery module compartment and setting the dehumidification start humidity value or temperature value. Although these solutions can solve the generation 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, and the temperature fluctuates greatly and is adjusted frequently.

[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, so as to avoid large temperature fluctuations at the battery. At the same time, the time of early start or stop is determined according to the battery charging and discharging power, and the battery temperature is accurately controlled to prevent condensation caused by excessively low battery temperature, and to avoid electrical short circuits caused by condensation, thereby ensuring system safety.

[0031] According to an embodiment of the present invention, a control method for an energy storage system is provided, 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 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 through the cold plate to the battery module to dissipate heat for the battery module. In this process, the starting cooling point is at the bottom of the battery module, and the temperature sampling point of the battery module is at the battery lug (the top of the battery). Due to the existence of thermal resistance, if the cooling effect of the liquid cooler is too strong, it will cause the battery module to produce large temperature fluctuations during the entire working process; if the cooling effect of the liquid cooler is not strong, the battery module will not be effectively cooled. Therefore, this scheme realizes the 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, avoids condensation and large temperature fluctuations at the battery module, and improves the accuracy of temperature control.

[0032] like Figure 1 The flow chart of an embodiment of the method of the present invention is shown in FIG. The control method of the energy storage system 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 obtained.

[0034] The control instructions of the battery module are sent by the user to the system to control the battery module to start charging and discharging or stop charging and discharging. The instructions include the battery module start charging and discharging instructions and the battery module stop charging and discharging instructions. When the user sets the battery module to start charging and discharging, he / she will also set the charging and discharging power and time, that is, the user sets the battery module to charge or discharge at a certain power within a certain time. When the battery module is charging and discharging, if the user manually controls the battery module to stop charging and discharging, or the charging and discharging time reaches the set time, the system will receive an instruction to stop charging or discharging. When the control instruction is to start charging and discharging, the system will obtain the charging and discharging power set by the user; when the control instruction is to stop charging and discharging, the system will obtain the current charging and discharging power of the battery module. After that, the system will control the liquid cooler to start or stop early according to the obtained charging and discharging 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 running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging.

[0036] Before the battery module is charged and discharged, the liquid cooler is controlled to start in advance, and the battery module is cooled in advance. When the battery module starts to charge and discharge, the cold energy can quickly and fully dissipate the heat for the battery module, avoiding the temperature control lag caused by the inconsistent temperature of the upper and bottom parts of the battery module due to the influence of thermal resistance, and preventing the temperature of the battery module from fluctuating greatly. At the same time, the time for the liquid cooler to start in advance is controlled according to the set charge and discharge power of the battery module to prevent condensation and ensure system safety.

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

[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 larger, and the temperature change will be more obvious. At this time, more cooling capacity is needed 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 longer in advance, so that the liquid cooler can provide more cooling capacity for the battery module in advance, thereby preventing the temperature of the battery module 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 according to 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 advance start time of the liquid cooler from being too short, resulting in large fluctuations in the temperature of the battery module.

[0041] Optionally, a linear relationship between the set charge and discharge power and the advance start time can also be established, in which the set charge and discharge power and the advance start time are in direct proportion, for example, the advance start time = k1*set charge and discharge power, where k1 is a coefficient greater than 0. Then, the corresponding advance start time can be determined according to the charge and discharge power set by the user and the 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 shut down, 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] Since the compressor of the liquid cooler needs a certain amount of time to stop completely when it stops, when the battery module and the liquid cooler stop at the same time, the liquid cooler will continue to run for a period of time. During this period of time, the battery module does not generate heat, and the temperature of the battery module will drop significantly, which is prone to condensation. Therefore, when the battery module is about to stop charging and discharging, the liquid cooler is controlled to stop in advance to prevent condensation. At the same time, the time when the liquid cooler stops in advance is controlled according to the charge and discharge power of the battery module to ensure that the temperature of the battery module will not rise significantly after the liquid cooler stops, which will affect the 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 according to 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 advance shutdown time of the liquid cooler based on the current charge and discharge power of the battery module, the corresponding advance 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 greater the advance shutdown time, so as to prevent the liquid cooler from shutting down too long in advance, causing large fluctuations in the temperature of the battery module.

[0048] Optionally, a linear relationship between the current charge and discharge power and the advance shutdown time may be established, in which the current charge and discharge power and the advance shutdown time are inversely proportional, for example, the advance shutdown time = k2*current charge and discharge power, where k2 is a coefficient less than 0. Then, the corresponding advance shutdown time may be determined based on the current charge and discharge power and the linear relationship.

[0049] 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 method also includes a process of adjusting the flow rate of the coolant during the charging and discharging process of the battery module, which specifically includes: during the charging or discharging process 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.

[0050] When the battery module is charging and discharging, the charging and discharging power may change, so the heat generated by the battery module is also changing. In order to match the cooling capacity provided by the liquid cooler with the heating capacity of the battery module and keep the temperature of the battery module within the set range, the opening of the regulating valve is controlled in real time according to the charging and discharging power, and the flow rate of the coolant is changed to prevent the battery module from condensing due to too low a temperature and reducing battery performance and safety due to too high a temperature. The charging and discharging power is directly proportional to the opening of the regulating valve. The greater the charging and discharging power, the greater the opening of the regulating valve, the greater the flow rate of the coolant, the more 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 where 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 currently daytime, and then 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 currently 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] Reference factors for target temperature correction include the ambient temperature of the battery module and the ambient dew point temperature. If the target temperature exceeds the ambient temperature, the battery module cannot be effectively cooled. If the target temperature is lower than the dew point temperature, condensation will occur at the battery module. Therefore, the target temperature is corrected to be between the dew point temperature and the ambient temperature.

[0058] The reference factor for target temperature correction also includes the current time, which is used to determine whether it is daytime or nighttime. After the user sets the battery module's charge and discharge strategy to photovoltaic self-consumption, the battery module is charged during the day and not charged at night. Therefore, the battery module generates more heat during the day and less heat at night. For example, the comparison data of the highest and lowest temperature points of the battery cells shown in the table below shows that the temperature difference is higher when discharging during the day than at night, where the daytime time period is 13:40-15:08 and the night time period is 18:30-19:45.

[0059]

[0060] Therefore, the target temperature can be further corrected according to the different heat generation of the battery module during the day and at night. The first time range corresponds to the daytime time period, such as 9:00-17:00, and the second time period corresponds to the night time period, such as 18:00-6:00. If it is daytime and the heat generation of the battery module is high, the target temperature of the liquid cooler can be appropriately reduced to improve the cooling effect of the liquid cooler; if it is night and the heat generation of the battery module is low, the target temperature of the liquid cooler can be appropriately increased to avoid condensation at the battery module. The first preset temperature value can be set to 0.5°C.

[0061] Optionally, during the daytime period, the sun's radiation intensity is different at different times, the battery module's charging power is different, and the heat generation is different, so the first time range can be divided more finely, and the corresponding target temperature adjustment amount is also different. For example, if it is currently 11:00-14:00, the battery module's charging power is high, and it can be reduced by 1°C based on the target temperature; if it is currently 14:00-17:00, the battery module's charging power is low, and it can be reduced by 0.5°C based on the target temperature.

[0062] According to the technical solution of this embodiment, when the control instruction of the battery module is 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, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is to stop charging or discharging the battery module, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 the 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 through the cold plate to the battery module to dissipate heat for the battery module. In this process, the starting cooling point is at the bottom of the battery module, and the temperature sampling point of the battery module is at the battery ear (the top of the battery). Due to the existence of thermal resistance, if the cooling effect of the liquid cooler is too strong, it will cause the battery module to produce large temperature fluctuations during the entire working process; if the cooling effect of the liquid cooler is not strong, it will achieve the effect of not effectively cooling the battery module. Therefore, this scheme realizes the pre-regulation of the liquid cooler before and after the shutdown of the energy storage system according to the charging and discharging strategy of the battery module, avoids condensation and large temperature fluctuations at the battery module, and improves the accuracy of temperature control.

[0064] See also Figure 3 The schematic diagram of the structure of an embodiment of the device of the present invention is shown. 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 refer to step S110.

[0066] The control instructions of the battery module are sent by the user to the system to control the battery module to start charging and discharging or stop charging and discharging. The instructions include the battery module start charging and discharging instructions and the battery module stop charging and discharging instructions. When the user sets the battery module to start charging and discharging, he / she will also set the charging and discharging power and time, that is, the user sets the battery module to charge or discharge at a certain power within a certain time. When the battery module is charging and discharging, if the user manually controls the battery module to stop charging and discharging, or the charging and discharging time reaches the set time, the system will receive an instruction to stop charging or discharging. When the control instruction is to start charging and discharging, the system will obtain the charging and discharging power set by the user; when the control instruction is to stop charging and discharging, the system will obtain the current charging and discharging power of the battery module. After that, the system will control the liquid cooler to start or stop early according to the obtained charging and discharging power.

[0067] The control unit 104 is configured to, when the control instruction of the battery module is an instruction to start charging or discharging the battery module, determine the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module; then control the liquid cooler to start, and after the running time of the liquid cooler reaches the advance start time, control the battery module to start charging or discharging. The specific functions and processing of the control unit 104 refer to step S120.

[0068] Before the battery module is charged and discharged, the liquid cooler is controlled to start in advance, and the battery module is cooled in advance. When the battery module starts to charge and discharge, the cold energy can quickly and fully dissipate the heat for the battery module, avoiding the temperature control lag caused by the inconsistent temperature of the upper and bottom parts of the battery module due to the influence of thermal resistance, and preventing the temperature of the battery module from fluctuating greatly. At the same time, the time for the liquid cooler to start in advance is controlled according to the set charge and discharge power of the battery module to prevent condensation and ensure system safety.

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

[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 larger, and the temperature change will be more obvious. At this time, more cooling capacity is needed 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 longer in advance, so that the liquid cooler can provide more cooling capacity for the battery module in advance, thereby preventing the temperature of the battery module 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 according to 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 advance start time of the liquid cooler from being too short, resulting in large fluctuations in the temperature of the battery module.

[0073] Optionally, a linear relationship between the set charge and discharge power and the advance start time can also be established, in which the set charge and discharge power and the advance start time are in direct proportion, for example, the advance start time = k1*set charge and discharge power, where k1 is a coefficient greater than 0. Then, the corresponding advance start time can be determined according to the charge and discharge power set by the user and the linear relationship.

[0074] The control unit 104 is further configured to, when the control instruction of the battery module is an instruction to stop charging or discharging the battery module, determine the advance shutdown time of the liquid cooler according to 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 shutdown time of the liquid cooler reaches the advance shutdown time. The specific functions and processing of the control unit 104 refer to step S130.

[0075] Since the compressor of the liquid cooler needs a certain amount of time to stop completely when it stops, when the battery module and the liquid cooler stop at the same time, the liquid cooler will continue to run for a period of time. During this period of time, the battery module does not generate heat, and the temperature of the battery module will drop significantly, which is prone to condensation. Therefore, when the battery module is about to stop charging and discharging, the liquid cooler is controlled to stop in advance to prevent condensation. At the same time, the time when the liquid cooler stops in advance is controlled according to the charge and discharge power of the battery module to ensure that the temperature of the battery module will not rise significantly after the liquid cooler stops, which will affect the 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 advance shutdown time of the liquid cooler according to the current charging power or discharging power of the battery module, including: judging according to 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.

[0079] When determining the advance shutdown time of the liquid cooler based on the current charge and discharge power of the battery module, the corresponding advance 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 greater the advance shutdown time, so as to prevent the liquid cooler from shutting down too long in advance, causing large fluctuations in the temperature of the battery module.

[0080] Optionally, a linear relationship between the current charge and discharge power and the advance shutdown time may be established, in which the current charge and discharge power and the advance shutdown time are inversely proportional, for example, the advance shutdown time = k2*current charge and discharge power, where k2 is a coefficient less than 0. Then, the corresponding advance shutdown time may be determined based on the current charge and discharge power and the 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 also specifically configured to: during the process of charging or discharging 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.

[0082] When the battery module is charging and discharging, the charging and discharging power may change, so the heat generated by the battery module is also changing. In order to match the cooling capacity provided by the liquid cooler with the heating capacity of the battery module and keep the temperature of the battery module within the set range, the opening of the regulating valve is controlled in real time according to the charging and discharging power, and the flow rate of the coolant is changed to prevent the battery module from condensing due to too low a temperature and reducing battery performance and safety due to too high a temperature. The charging and discharging power is directly proportional to the opening of the regulating valve. The greater the charging and discharging power, the greater the opening of the regulating valve, the greater the flow rate of the coolant, the more 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 where the battery module is located, the ambient temperature of the battery module, and the current time. The specific functions and processing of the acquisition unit 102 refer to step S210.

[0085] The control unit 104 is further configured to adjust the target temperature of the liquid cooler after the user sets 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 refer to step S220.

[0086] The control unit 104 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 and it is considered that it is daytime. The specific functions and processing of the control unit 104 refer to step S230.

[0087] The control unit 104 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 and it is considered that it is night. The specific functions and processing of the control unit 104 refer to 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] Reference factors for target temperature correction include the ambient temperature of the battery module and the ambient dew point temperature. If the target temperature exceeds the ambient temperature, the battery module cannot be effectively cooled. If the target temperature is lower than the dew point temperature, condensation will occur at the battery module. Therefore, the target temperature is corrected to be between the dew point temperature and the ambient temperature.

[0090] The reference factor for target temperature correction also includes the current time, which is used to determine whether it is daytime or nighttime. After the user sets the battery module's charge and discharge strategy to photovoltaic self-consumption, the battery module is charged during the day and not charged at night. Therefore, the battery module generates more heat during the day and less heat at night. For example, the comparison data of the highest and lowest temperature points of the battery cells shown in the table below shows that the temperature difference is higher when discharging during the day than at night, where the daytime time period is 13:40-15:08 and the night time period is 18:30-19:45.

[0091]

[0092]

[0093] Therefore, the target temperature can be further corrected according to the different heat generation of the battery module during the day and at night. The first time range corresponds to the daytime time period, such as 9:00-17:00, and the second time period corresponds to the night time period, such as 18:00-6:00. If it is daytime and the heat generation of the battery module is high, the target temperature of the liquid cooler can be appropriately reduced to improve the cooling effect of the liquid cooler; if it is night and the heat generation of the battery module is low, the target temperature of the liquid cooler can be appropriately increased to avoid condensation at the battery module. The first preset temperature value can be set to 0.5°C.

[0094] Optionally, during the daytime period, the sun's radiation intensity is different at different times, the battery module's charging power is different, and the heat generation is different, so the first time range can be divided more finely, and the corresponding target temperature adjustment amount is also different. For example, if it is currently 11:00-14:00, the battery module's charging power is high, and it can be reduced by 1°C based on the target temperature; if it is currently 14:00-17:00, the battery module's charging power is low, and it can be reduced by 0.5°C based on the target temperature.

[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 the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0096] According to the technical solution of the present invention, when the control instruction of the battery module is 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, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is to stop charging or discharging the battery module, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0099] According to the technical solution of the present invention, when the control instruction of the battery module is 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, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is to stop charging or discharging the battery module, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 executed, 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 the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0102] According to the technical solution of the present invention, when the control instruction of the battery module is 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, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is to stop charging or discharging the battery module, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 control method of the energy storage system is also provided. The computer program product includes a computer program. When the computer program product is processed and executed, the steps of the control method of the energy storage system 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 the 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 control instruction of the battery module is 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, and then the liquid cooler is controlled to start, and after the running time of the liquid cooler reaches the advance start time, the battery module is controlled to start charging or discharging; when the control instruction of the battery module is to stop charging or discharging the battery module, the advance stop 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 stop time of the liquid cooler 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 charging or discharging and stops charging or discharging, large temperature fluctuations of the battery module are avoided, and at the same time, the time of early start or stop is determined according to the charging and discharging power, the accuracy of temperature control is improved, condensation of 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 above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

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: 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; 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 running time of the liquid cooler reaches the advance start time, the battery module is controlled 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 cooling liquid circulating in the liquid cooler; The method further comprises: During the process of charging or discharging 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 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 within 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, 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; 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: Determine 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 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 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: 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 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 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 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.

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; 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 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 the advance start time of the liquid cooler according to the set charging power or discharging power of the battery module; then control the liquid cooler to start, and after the running time of the liquid cooler reaches the advance start time, control the battery module to start charging or discharging; 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 shut down, and control the battery module to stop charging or discharging after the shutdown time of the liquid cooler reaches the advance shutdown time.

8. An energy storage system, characterized in that: include: The control device of the energy storage system as claimed in 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 control method of the energy storage system 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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