Energy storage system SOC equalization method and device, controller and storage medium
Patent Information
- Application Number
- CN202411356878.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2025-01-14
Smart Images
Figure CN119315602A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the technical field of energy storage systems, and in particular, relates to a SOC balancing method, device, controller and storage medium for an energy storage system. Background Art
[0002] In the related art, the DC-coupled energy storage system gives priority to meeting the grid-connected port power in the grid-connected priority daytime discharge mode and the power of the inverter unit is evenly distributed. Since the photovoltaic power is uncertain with the intensity of light and the DC / DC constant voltage mode is operated, the energy storage system has inconsistent charge states (SOCs) corresponding to the inverter units during the discharge process, resulting in increased SOC differences and low energy utilization of the energy storage system. Summary of the invention
[0003] The present application proposes a method, device, controller and storage medium for SOC balancing of an energy storage system to solve the problem in the related art that the SOC state of charge (SOC) corresponding to the inverter units is inconsistent, resulting in increased SOC differences and low energy utilization of the energy storage system.
[0004] In a first aspect, the present application provides a method for balancing SOC of an energy storage system, the method comprising:
[0005] Obtain the grid connection mode of the energy storage system;
[0006] When the grid-connected mode of the energy storage system is the first mode, allocating grid-connected power to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system;
[0007] The first mode is a grid-connected mode with priority to daytime discharge, and the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
[0008] The energy storage system SOC balancing method provided in the embodiment of the present application allocates grid-connected power to each inverter unit according to the SOC weight of the state of charge corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system when the grid-connected mode of the energy storage system is the grid-connected priority daytime discharge mode. This can reduce the gap between the SOCs of each inverter unit, meet the charging needs of each inverter unit, shorten the SOCs of each inverter unit without increasing hardware facilities, reduce the loss caused by abandoned light of the energy storage system, and improve the energy utilization and work efficiency of the energy storage system.
[0009] According to an embodiment of the present application, when the grid-connected mode of the energy storage system is the first mode, the grid-connected power is allocated to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system, including:
[0010] Allocate temporary power to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system;
[0011] A smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined, and grid-connected power is allocated to each inverter unit according to the smaller value.
[0012] In the above technical scheme, temporary power is allocated to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system, and the smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined. The grid-connected power is allocated to each inverter unit according to the smaller value. This allows each inverter unit to allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby meeting the charging needs of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOCs of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0013] According to an embodiment of the present application, allocating grid-connected power to each inverter unit according to the smaller value includes:
[0014] If the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit.
[0015] In the above technical solution, if the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit, so that the inverter unit can allocate temporary power according to the SOC weight within a safe range, meet the charging needs of each inverter unit, reduce the gap between the SOCs of each inverter unit, maintain the consistency of the SOCs of each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0016] According to an embodiment of the present application, allocating grid-connected power to each inverter unit according to the smaller value includes:
[0017] If the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit;
[0018] According to the SOC weights of the other inverter units and the first grid-connected power, temporary power is re-allocated to the other inverter units, wherein the other inverter units are inverter units other than the target inverter unit, and the first grid-connected power is the power obtained by subtracting the rated power of the target inverter unit from the grid-connected power corresponding to the energy storage system;
[0019] The grid-connected power of each of the other inverter units is determined according to the reallocated temporary power and the rated power of each of the other inverter units.
[0020] In the above technical solution, if the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit, and the temporary power is reallocated to the other inverter units according to the SOC weights of the other inverter units except the target inverter unit and the first grid-connected power. This allows each inverter unit to allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby meeting the charging needs of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOCs of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0021] According to one embodiment of the present application, the method further includes:
[0022] Obtaining the SOC weight of each inverter unit;
[0023] The rated power of each inverter unit is obtained.
[0024] In the above technical solution, by obtaining the SOC weight of each inverter unit and determining the rated power of each inverter unit, each inverter unit can allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby narrowing the SOC of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOC of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0025] According to an embodiment of the present application, obtaining the SOC weight of each inverter unit includes:
[0026] Obtain the SOC corresponding to each inverter unit;
[0027] The SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units.
[0028] In the above technical solution, by acquiring the SOC corresponding to each inverter unit, the SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units, and the grid-connected power can be allocated to each inverter unit according to the SOC weight of each inverter unit to meet the charging needs of each inverter unit, reduce the gap between the SOCs of each inverter unit, maintain the consistency of the SOCs of each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0029] According to an embodiment of the present application, obtaining the rated power of each inverter unit includes:
[0030] Obtaining the rated power of the inverter and the total number of the inverter units;
[0031] The rated power of each inverter unit is determined according to the rated power of the inverter and the total number of the inverter units.
[0032] In the above technical solution, by obtaining the rated power of the inverter and the total number of inverter units, the rated power of each inverter unit is determined according to the rated power of the inverter and the total number of inverter units. This can make the grid-connected power sent by the energy storage system to each inverter unit less than or equal to the rated power of each inverter unit, reduce the difference in the state of charge SOC corresponding to each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0033] In a second aspect, the present application provides an energy storage system SOC balancing device, the device comprising:
[0034] An acquisition unit, used for acquiring a grid-connected mode of an energy storage system;
[0035] a processing unit, configured to allocate grid-connected power to each inverter unit according to a state of charge SOC weight corresponding to each inverter unit and a grid-connected power corresponding to the energy storage system when the grid-connected mode of the energy storage system is the first mode;
[0036] The first mode is a grid-connected mode with priority to daytime discharge, and the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
[0037] In the above technical solution, when the grid-connected mode of the energy storage system is the grid-connected priority daytime discharge mode, the grid-connected power is allocated to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system. This can reduce the gap between the SOCs of each inverter unit and meet the charging needs of each inverter unit. Without increasing hardware facilities, the SOCs of each inverter unit are shortened, the losses caused by the abandoned light of the energy storage system are reduced, and the energy utilization and work efficiency of the energy storage system are improved.
[0038] In a third aspect, the present application provides a controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the energy storage system SOC balancing method as described in the first aspect above is implemented.
[0039] In a fourth aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the energy storage system SOC balancing method as described in the first aspect above is implemented.
[0040] In a fifth aspect, the present application provides a chip, comprising a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run a program or instruction to implement the energy storage system SOC balancing method as described in the first aspect.
[0041] In a sixth aspect, the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the energy storage system SOC balancing method as described in the first aspect above.
[0042] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:
[0044] Figure 1 It is one of the flow charts of the SOC balancing method of the energy storage system provided in the embodiment of the present application;
[0045] Figure 2 is a schematic diagram of the structure of the energy storage system provided in the embodiment of the present application;
[0046] Figure 3 It is a flowchart of a method for obtaining the SOC weight of each inverter unit provided in an embodiment of the present application;
[0047] Figure 4 This is the second flow chart of the SOC balancing method for the energy storage system provided in the embodiment of the present application;
[0048] Figure 5 is a schematic diagram of a SOC balancing device for an energy storage system provided in an embodiment of the present application;
[0049] Figure 6 It is a schematic diagram of a controller provided in an embodiment of the present application.
[0050] Description of reference numerals:
[0051] 20: Energy storage system; 201: Renewable energy; 202: Energy storage battery;
[0052] 203: inverter system; 204: power grid; 205: load;
[0053] 50: energy storage system SOC balancing device; 501: acquisition unit; 502: processing unit;
[0054] 600: controller; 601: processor; 602: memory. DETAILED DESCRIPTION
[0055] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.
[0056] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.
[0057] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.
[0058] The energy storage system SOC balancing method provided in the embodiment of the present application, the execution subject of the energy storage system SOC balancing method can be a controller or a functional module or functional entity in the controller that can implement the energy storage system SOC balancing method. The controller mentioned in the embodiment of the present application includes but is not limited to a controller, a battery management module, a battery management system, an inverter control module or a submodule controller (Submodule Controller, SMC) in the energy storage system. The energy storage system SOC balancing method provided in the embodiment of the present application is described below by taking the controller as an execution subject as an example.
[0059] In the power system, the grid-connected priority daytime discharge mode means that during the daytime period, the output power of renewable energy is supplied to the grid first to meet the grid demand. The power obtained by deducting the power supplied to the grid (i.e. the grid-connected power) from the output power of renewable energy will be supplied to the energy storage battery for charging.
[0060] In the related art, the DC-coupled energy storage system gives priority to meeting the grid-connected port power in the grid-connected priority daytime discharge mode and the power of the inverter unit is evenly distributed. Since the photovoltaic power is uncertain with the intensity of light and the DC / DC constant voltage mode is operated, the energy storage system has inconsistent charge states (SOCs) corresponding to the inverter units during the discharge process, resulting in increased SOC differences and low energy utilization of the energy storage system.
[0061] In order to solve the above problems, the present application provides an energy storage system SOC balancing method, device, controller and storage medium. The following, in combination with the accompanying drawings, the energy storage system SOC balancing method, device, controller and storage medium provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.
[0062] Figure 1 is one of the flow charts of the SOC balancing method for the energy storage system provided in the embodiment of the present application, such as Figure 1 As shown, the energy storage system SOC balancing method includes: step 110 and step 120.
[0063] Step 110: Obtaining a grid-connected mode of the energy storage system;
[0064] It is easy to understand that the energy storage system includes renewable energy, energy storage batteries, inverter systems, power grids and loads. According to the different coupling methods between renewable energy and energy storage batteries, the energy storage system is divided into DC-coupled energy storage system and AC-coupled energy storage system.
[0065] In a DC-coupled energy storage system, renewable energy and energy storage equipment are directly connected to the inverter system. The electric energy generated by renewable energy and the power grid is stored in the energy storage device through the inverter system, and the energy is collected on the energy storage device side.
[0066] Optionally, the grid-connected mode of the energy storage system includes a first mode, which is a grid-connected mode with priority during daytime discharge. When the energy storage system is in the grid-connected mode with priority during daytime discharge, the output power of renewable energy is preferentially supplied to the grid to meet the grid demand. The power obtained by deducting the power supplied to the grid (i.e., the grid-connected power) from the output power of renewable energy will be supplied to the energy storage system for charging. The embodiment of the present application controls the grid-connected power according to the SOC of the battery module to adjust the charging and discharging of the energy storage battery.
[0067] Step 120: when the grid-connected mode of the energy storage system is the first mode, the grid-connected power is allocated to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system.
[0068] When the energy storage system is in the grid-connected priority daytime discharge mode, the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit. The grid-connected power can be allocated to each inverter unit according to the SOC weight of the battery module under each inverter unit and the grid-connected power corresponding to the energy storage system.
[0069] Taking the renewable energy as photovoltaic components as an example, when the photovoltaic components meet the load demand and have surplus energy, the energy storage system allocates grid-connected power to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system. The larger the SOC of the inverter unit, the larger the grid-connected power allocated to the inverter unit. The SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
[0070] Figure 2 is a schematic diagram of the structure of the energy storage system provided in the embodiment of the present application, such as Figure 2 As shown, the energy storage system 20 includes renewable energy 201, energy storage battery 202, inverter system 203, power grid 204 and load 205, and the inverter system 203 includes at least one inverter unit.
[0071] Allocating high grid-connected power to inverter units with high SOC can reduce the photovoltaic surplus power shared by inverter units with high SOC, and allocating low grid-connected power to inverter units with low SOC can increase the photovoltaic surplus power shared by inverter units with low SOC. Among them, photovoltaic surplus power refers to the power after deducting the grid-connected power from the output power of the photovoltaic module.
[0072] Optionally, when the sunlight is strong, the energy storage system charges the battery by reducing the photovoltaic surplus power shared by the inverter unit with a high SOC and increasing the photovoltaic surplus power shared by the inverter unit with a low SOC, thereby achieving SOC balance.
[0073] Optionally, when the light is weak, SOC balancing can be achieved by reducing the discharge capacity of the inverter unit batteries with low SOC and increasing the discharge capacity of the inverter unit batteries with high SOC.
[0074] The energy storage system SOC balancing method provided in the embodiment of the present application allocates grid-connected power to each inverter unit according to the SOC weight of the state of charge corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system when the grid-connected mode of the energy storage system is the grid-connected priority daytime discharge mode. This can reduce the gap between the SOCs of each inverter unit, meet the charging needs of each inverter unit, shorten the SOCs of each inverter unit without increasing hardware facilities, reduce the loss caused by abandoned light of the energy storage system, and improve the energy utilization and work efficiency of the energy storage system.
[0075] In one embodiment of the present application, when the grid-connected mode of the energy storage system is the first mode, the grid-connected power is allocated to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system, including:
[0076] Allocate temporary power to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system;
[0077] A smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined, and grid-connected power is allocated to each inverter unit according to the smaller value.
[0078] It is easy to understand that the energy storage system allocates temporary power to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system. For example, the grid-connected power corresponding to the energy storage system is P, the total number of inverter units is N, i is the i-th inverter unit, the value of i ranges from 1 to N, and the SOC corresponding to the i-th inverter unit is SOC i The total SOC corresponding to each inverter unit is The SOC weight of the i-th inverter unit is The temporary power allocated to the i-th inverter unit is as follows:
[0079]
[0080] Among them, P temp is the temporary power allocated to the i-th inverter unit, P is the grid-connected power corresponding to the energy storage system, is the SOC weight of the i-th inverter unit.
[0081] It is worth noting that the sum of the temporary powers allocated to each inverter unit is the grid-connected power corresponding to the energy storage system. For example, the grid-connected power corresponding to the energy storage system is P, the total number of inverter units is N, i is the i-th inverter unit, the value of i ranges from 1 to N, and the power allocated to the i-th inverter unit is P i , satisfying the following formula:
[0082]
[0083] It should be noted that the energy storage system determines the smaller value between the temporary power of each inverter unit and the rated power of each inverter unit, and allocates the grid-connected power to each inverter unit according to the smaller value. For example, P temp The temporary power allocated to the i-th inverter unit, P unit is the rated power of the i-th inverter unit, and the power allocated to the i-th inverter unit is P i Satisfies the following formula:
[0084] P i =min(P temp ,P unit )
[0085] In the above technical scheme, temporary power is allocated to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system, and the smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined. The grid-connected power is allocated to each inverter unit according to the smaller value. This allows each inverter unit to allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby meeting the charging needs of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOCs of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0086] In one embodiment of the present application, allocating grid-connected power to each inverter unit according to the smaller value includes:
[0087] If the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit.
[0088] It is easy to understand that if the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit. For example, the temporary power allocated to the target inverter unit is P temp , the rated power of the target inverter unit is P unit , if P temp <P unit , then P temp is the grid-connected power of the target inverter unit.
[0089] In the above technical solution, if the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit, so that the inverter unit can allocate temporary power according to the SOC weight within a safe range, meet the charging needs of each inverter unit, reduce the gap between the SOCs of each inverter unit, maintain the consistency of the SOCs of each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0090] In one embodiment of the present application, allocating grid-connected power to each inverter unit according to the smaller value includes:
[0091] If the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit;
[0092] According to the SOC weights of the other inverter units and the first grid-connected power, temporary power is re-allocated to the other inverter units, wherein the other inverter units are inverter units other than the target inverter unit, and the first grid-connected power is the power obtained by subtracting the rated power of the target inverter unit from the grid-connected power corresponding to the energy storage system;
[0093] The grid-connected power of each of the other inverter units is determined according to the reallocated temporary power and the rated power of each of the other inverter units.
[0094] It is easy to understand that if the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit will be used as the grid-connected power of the target inverter unit, and the temporary power of other inverter units except the target inverter unit will be reallocated according to the first grid-connected power and the SOC weights of the other inverter units.
[0095] It should be noted that the first grid-connected power is the power obtained by subtracting the rated power of the target inverter unit from the grid-connected power corresponding to the energy storage system. For example, the grid-connected power corresponding to the energy storage system is P, and the rated power of the target inverter unit is P unit , the first grid-connected power P ′ =PP unit .
[0096] The grid-connected power of other inverter units is determined based on the reallocated temporary power and the rated power of other inverter units. If the reallocated temporary power in other inverter units is greater than or equal to the rated power of the inverter unit, the rated power of the inverter unit is used as the grid-connected power of the inverter unit, and the remaining inverter units are reallocated temporary power according to the SOC weight and the second grid-connected power, and so on, until all inverter units have allocated temporary power.
[0097] In the above technical solution, if the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit, and the temporary power is reallocated to the other inverter units according to the SOC weights of the other inverter units except the target inverter unit and the first grid-connected power. This allows each inverter unit to allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby meeting the charging needs of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOCs of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0098] In one embodiment of the present application, the method further comprises:
[0099] Obtaining the SOC weight of each inverter unit;
[0100] The rated power of each inverter unit is obtained.
[0101] It is easy to understand that the energy storage system obtains the SOC weight of each inverter unit, allocates temporary power to each inverter unit according to the SOC weight of each inverter unit, determines the rated power of each inverter unit, and if the temporary power allocated to an inverter unit is greater than the rated power of each inverter unit, the power of the inverter unit is adjusted to the rated power.
[0102] In the above technical solution, by obtaining the SOC weight of each inverter unit and determining the rated power of each inverter unit, each inverter unit can allocate temporary power according to the SOC weight without exceeding the rated power of each inverter unit, thereby narrowing the SOC of each inverter unit, reducing the gap between the SOCs of each inverter unit, maintaining the consistency of the SOC of each inverter unit, and improving the energy utilization and work efficiency of the energy storage system.
[0103] In one embodiment of the present application, the obtaining of the SOC weight of each inverter unit includes:
[0104] Obtain the SOC corresponding to each inverter unit;
[0105] The SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units.
[0106] Figure 3 is a flow chart of a method for obtaining the SOC weight of each inverter unit provided in an embodiment of the present application, such as Figure 3 As shown, the method includes step 310 and step 320.
[0107] Step 310, obtaining the SOC corresponding to each inverter unit;
[0108] It is easy to understand that the energy storage system obtains the state of charge SOC corresponding to each inverter unit. For example, the total number of inverter units is N, i is the i-th inverter unit, the value of i is 1 to N, and the SOC corresponding to the i-th inverter unit is SOC i .
[0109] Step 320: Obtain the SOC weight of each inverter unit according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units.
[0110] It is easy to understand that the energy storage system obtains the SOC weight of each inverter unit according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units. For example, the total number of inverter units is N, i is the i-th inverter unit, the value of i is 1 to N, and the SOC corresponding to the i-th inverter unit is SOC i , the total SOC corresponding to each inverter unit is The SOC weight of the i-th inverter unit is as follows:
[0111]
[0112] Among them, SOC i is the SOC of the i-th inverter unit, is the total SOC corresponding to N inverter units, and N is the total number of inverter units.
[0113] In the above technical solution, by acquiring the SOC corresponding to each inverter unit, the SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units, and the grid-connected power can be allocated to each inverter unit according to the SOC weight of each inverter unit to meet the charging needs of each inverter unit, reduce the gap between the SOCs of each inverter unit, maintain the consistency of the SOCs of each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0114] In one embodiment of the present application, the obtaining of the rated power of each inverter unit includes:
[0115] Obtaining the rated power of the inverter and the total number of the inverter units;
[0116] The rated power of each inverter unit is determined according to the rated power of the inverter and the total number of the inverter units.
[0117] It is easy to understand that the energy storage system obtains the rated power of the inverter and the total number of inverter units. For example, the rated power of the inverter is P rate , the total number of inverter units is N.
[0118] The energy storage system determines the rated power of each inverter unit according to the rated power of the inverter and the total number of inverter units. For example, the rated power of the inverter is P rate , the total number of inverter units is N, and the rated power of each inverter unit is P unit =P rate / N.
[0119] It should be noted that the rated power of each inverter unit is the upper limit of the inverter unit discharge, and the grid-connected power sent by the energy storage system to each inverter unit is less than or equal to the rated power of each inverter unit.
[0120] Figure 4 This is the second flow chart of the SOC balancing method for the energy storage system provided in the embodiment of the present application, such as Figure 4 As shown, in the case of grid-connected priority discharge during the day, P is the grid-connected power value received by the energy storage battery. When P>0, the total number of inverter units is N, i is the i-th inverter unit, and the value of i ranges from 1 to N. When i=1, the SOC corresponding to the i-th inverter unit is obtained, and the SOC weight of the i-th inverter unit is obtained according to the SOC corresponding to the i-th inverter unit and the total SOC corresponding to each inverter unit. It is judged whether the weights of all inverter units are allocated. If not, the number i is automatically increased by 1, and the SOC weight of the next inverter unit is allocated.
[0121] After the weight distribution of all inverter units is completed, the grid-connected power P is allocated to the i-th inverter unit according to the SOC weight corresponding to the i-th inverter unit and the grid-connected power corresponding to the energy storage system. i , it is determined whether the power of all inverter units has been allocated. If not, the number i is incremented by 1, and the grid-connected power of the next inverter unit is allocated until the grid-connected power of N inverter units is allocated.
[0122] In the above technical solution, by obtaining the rated power of the inverter and the total number of inverter units, the rated power of each inverter unit is determined according to the rated power of the inverter and the total number of inverter units. This can make the grid-connected power sent by the energy storage system to each inverter unit less than or equal to the rated power of each inverter unit, reduce the difference in the state of charge SOC corresponding to each inverter unit, and improve the energy utilization and work efficiency of the energy storage system.
[0123] Figure 5 is a schematic diagram of a SOC balancing device for an energy storage system provided in an embodiment of the present application, such as Figure 5 As shown, the energy storage system SOC balancing device 50 includes an acquisition unit 501 and a processing unit 502 .
[0124] An acquisition unit 501 is used to acquire a grid-connected mode of an energy storage system;
[0125] The processing unit 502 is used to allocate the grid-connected power to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system when the grid-connected mode of the energy storage system is the first mode;
[0126] The first mode is a grid-connected mode with priority to daytime discharge, and the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
[0127] Optionally, the processing unit 502 is further configured to:
[0128] Allocate temporary power to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system;
[0129] A smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined, and grid-connected power is allocated to each inverter unit according to the smaller value.
[0130] Optionally, the processing unit 502 is further configured to:
[0131] If the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit.
[0132] Optionally, the processing unit 502 is further configured to:
[0133] If the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit;
[0134] According to the SOC weights of the other inverter units and the first grid-connected power, temporary power is re-allocated to the other inverter units, wherein the other inverter units are inverter units other than the target inverter unit, and the first grid-connected power is the power obtained by subtracting the rated power of the target inverter unit from the grid-connected power corresponding to the energy storage system;
[0135] The grid-connected power of each of the other inverter units is determined according to the reallocated temporary power and the rated power of each of the other inverter units.
[0136] Optionally, the acquiring unit 501 is further configured to:
[0137] Obtaining the SOC weight of each inverter unit;
[0138] The rated power of each inverter unit is obtained.
[0139] Optionally, the obtaining the SOC weight of each inverter unit includes:
[0140] Obtain the SOC corresponding to each inverter unit;
[0141] The SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units.
[0142] Optionally, the obtaining the rated power of each inverter unit includes:
[0143] Obtaining the rated power of the inverter and the total number of the inverter units;
[0144] The rated power of each inverter unit is determined according to the rated power of the inverter and the total number of the inverter units.
[0145] In the above technical solution, when the grid-connected mode of the energy storage system is the grid-connected priority daytime discharge mode, the grid-connected power is allocated to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system. This can reduce the gap between the SOCs of each inverter unit and meet the charging needs of each inverter unit. Without increasing hardware facilities, the SOCs of each inverter unit are shortened, the losses caused by the abandoned light of the energy storage system are reduced, and the energy utilization and work efficiency of the energy storage system are improved.
[0146] The energy storage system SOC balancing device 50 in the embodiment of the present application may be a controller, or a component in the controller, such as an integrated circuit or a chip.
[0147] The energy storage system SOC balancing device 50 in the embodiment of the present application may be a device having an operating system. The operating system may be a Microsoft (Windows) operating system, an Android (Android) operating system, an IOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.
[0148] The energy storage system SOC balancing device 50 provided in the embodiment of the present application can achieve Figures 1 to 4 To avoid repetition, the various processes implemented by the method embodiment are not described here.
[0149] In some embodiments, Figure 6 As shown, the embodiment of the present application also provides a controller 600, including a processor 601, a memory 602, and a computer program stored in the memory 602 and executable on the processor 601. When the program is executed by the processor 601, each process of the above-mentioned energy storage system SOC balancing method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.
[0150] Optionally, the controller may be a local controller of the energy storage system, wherein the local controller is used to monitor, manage, control and protect the energy storage battery and the inverter, and execute each process of the above-mentioned energy storage system SOC balancing method embodiment.
[0151] Optionally, the controller may be a battery management module, a battery management system, an inverter control module or a submodule controller (SMC), etc.
[0152] The embodiment of the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, each process of the above-mentioned energy storage system SOC balancing method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.
[0153] The processor is the processor in the controller described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.
[0154] An embodiment of the present application also provides a computer program product, including a computer program, which implements the above-mentioned energy storage system SOC balancing method when executed by a processor.
[0155] The processor is the processor in the controller described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.
[0156] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned energy storage system SOC balancing method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.
[0157] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.
[0158] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.
[0159] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.
[0160] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.
[0161] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.
[0162] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.
Claims
1. A method for balancing SOC of an energy storage system, characterized in that: include: Obtain the grid connection mode of the energy storage system; When the grid-connected mode of the energy storage system is the first mode, allocating grid-connected power to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system; The first mode is a grid-connected mode with priority to daytime discharge, and the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
2. The energy storage system SOC balancing method according to claim 1, characterized in that: When the grid-connected mode of the energy storage system is the first mode, allocating the grid-connected power to each inverter unit according to the state of charge SOC weight corresponding to each inverter unit and the grid-connected power corresponding to the energy storage system includes: Allocate temporary power to each inverter unit according to the SOC weight of each inverter unit and the grid-connected power corresponding to the energy storage system; A smaller value between the temporary power of each inverter unit and the rated power of each inverter unit is determined, and grid-connected power is allocated to each inverter unit according to the smaller value.
3. The energy storage system SOC balancing method according to claim 2, characterized in that: Allocating grid-connected power to each inverter unit according to the smaller value includes: If the temporary power allocated to the target inverter unit is less than the rated power of the target inverter unit, the temporary power allocated to the target inverter unit is used as the grid-connected power of the target inverter unit.
4. The energy storage system SOC balancing method according to claim 2, characterized in that: Allocating grid-connected power to each inverter unit according to the smaller value includes: If the temporary power allocated to the target inverter unit is greater than or equal to the rated power of the target inverter unit, the rated power of the target inverter unit is used as the grid-connected power of the target inverter unit; According to the SOC weights of the other inverter units and the first grid-connected power, temporary power is re-allocated to the other inverter units, wherein the other inverter units are inverter units other than the target inverter unit, and the first grid-connected power is the power obtained by subtracting the rated power of the target inverter unit from the grid-connected power corresponding to the energy storage system; The grid-connected power of each of the other inverter units is determined according to the reallocated temporary power and the rated power of each of the other inverter units.
5. The energy storage system SOC balancing method according to any one of claims 2 to 4, characterized in that: The method further comprises: Obtaining the SOC weight of each inverter unit; The rated power of each inverter unit is obtained.
6. The energy storage system SOC balancing method according to claim 5, characterized in that: The obtaining of the SOC weight of each inverter unit includes: Obtain the SOC corresponding to each inverter unit; The SOC weight of each inverter unit is obtained according to the SOC corresponding to each inverter unit and the total SOC corresponding to all inverter units.
7. The energy storage system SOC balancing method according to claim 5, characterized in that: The obtaining of the rated power of each inverter unit includes: Obtaining the rated power of the inverter and the total number of the inverter units; The rated power of each inverter unit is determined according to the rated power of the inverter and the total number of the inverter units.
8. A SOC balancing device for an energy storage system, characterized in that: include: An acquisition unit, used for acquiring a grid-connected mode of an energy storage system; a processing unit, configured to allocate grid-connected power to each inverter unit according to a state of charge SOC weight corresponding to each inverter unit and a grid-connected power corresponding to the energy storage system when the grid-connected mode of the energy storage system is the first mode; The first mode is a grid-connected mode with priority to daytime discharge, and the SOC corresponding to each inverter unit is the SOC of the battery module under each inverter unit.
9. A controller comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the energy storage system SOC balancing method as described in any one of claims 1 to 7 is implemented.
10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the energy storage system SOC balancing method as described in any one of claims 1 to 7 is implemented.