Power control method and device, energy storage system and nonvolatile storage medium

Abstract

The application discloses a power control method and device, an energy storage system and a nonvolatile storage medium. The method comprises the following steps: acquiring the residual power of each battery unit in the energy storage system and the power direction and power size of a micro-grid connected with the energy storage system; determining the single battery optimal power of each battery unit matched with the power direction of the micro-grid and the single battery maximum power of each battery unit matched with the power direction of the micro-grid according to the residual power of each battery unit and the power direction of the micro-grid; determining the total optimal power and total maximum power of the battery units according to the single battery optimal power and the single battery maximum power; and determining the single battery actual power of each battery unit according to the total optimal power, the total maximum power and the power size of the micro-grid. The application solves the technical problem that the distribution of the battery power is not intelligent when each battery unit in the energy storage system is controlled to charge and discharge.

Description

Technical Field

[0001] This invention relates to the field of battery energy storage, and more specifically, to a power control method, apparatus, energy storage system, and non-volatile storage medium. Background Technology

[0002] An energy storage system is a system that stores energy, such as electrical energy, through various media and releases it when needed. An energy storage system can consist of multiple energy storage containers. Each container contains a battery cell, a Battery Management System (BMS) to monitor battery status, and a Power Conversion System (PCS) to convert the direct current (DC) generated by the battery into the alternating current (AC) required by the microgrid. It may also include cooling, fire suppression, lighting, and monitoring systems.

[0003] In current energy storage systems, the power input and output of battery cells are controlled by PCS during the charging and discharging process. PCS responds to the power demand of the grid side or microgrid side and distributes the power demand as evenly as possible to each PCS, provided that the power does not exceed the maximum tolerable power of the battery cell, thereby charging and discharging each battery cell.

[0004] The energy storage system and its energy balancing control method disclosed in patent application CN202011322379.X, as well as the photovoltaic-storage integrated multi-unit parallel system, balance the SOC by determining the average remaining state of charge (SOC) of the batteries and determining the balancing current based on the difference between the SOC of each battery module and the average SOC. However, this method is mostly applicable to the energy storage system in a static state. In the charging and discharging state, the average SOC changes in real time, and the method of superimposing the balancing current during the charging and discharging process of the DC-DC converter is extremely complex. Furthermore, this balancing method does not fully consider the characteristics of the batteries. When the battery capacity decreases, it is very likely due to cell degradation within the battery, referred to as a "short-chain battery." Frequent charging of short-chain batteries will further reduce their lifespan. The above process is not intelligent in its power distribution during battery charging and discharging in the energy storage system and has many problems.

[0005] There is currently no effective solution to the above problems. Summary of the Invention

[0006] This invention provides a power control method, device, energy storage system, and non-volatile storage medium to at least solve the technical problem of unintelligent power distribution of battery cells during charging and discharging in an energy storage system.

[0007] According to one aspect of the present invention, a power control method is provided, comprising: acquiring the remaining charge of each of a plurality of battery cells in an energy storage system and the power direction and power magnitude of a microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes a charging direction or a discharging direction; determining, based on the remaining charge of each of the plurality of battery cells and the power direction of the microgrid, the optimal power of each single cell of the plurality of battery cells matching the power direction of the microgrid, and determining the maximum power of each single cell of the plurality of battery cells matching the power direction of the microgrid; determining, based on the optimal power of each single cell of the plurality of battery cells and the maximum power of each single cell of the plurality of battery cells, the total optimal power and the total maximum power of the plurality of battery cells; and determining, based on the total optimal power, the total maximum power, and the power magnitude of the microgrid, the actual power of each single cell of the plurality of battery cells.

[0008] Optionally, determining the optimal single-cell power of each of the plurality of battery cells matching the power direction of the microgrid, and determining the maximum single-cell power of each of the plurality of battery cells matching the power direction of the microgrid, based on the remaining charge of each of the plurality of battery cells and the power direction of the microgrid, includes: when the power direction of the microgrid is that the microgrid is supplying power to the energy storage system, calling up the optimal charging power curve and the maximum charging power curve of each of the plurality of battery cells; determining the optimal charging power of each of the plurality of battery cells and the maximum charging power curve of each of the plurality of battery cells based on the optimal charging power curve, the maximum charging power curve of each of the plurality of battery cells and the remaining charge of each of the battery cells. The maximum charging power of each battery unit, wherein the optimal power of a single battery includes the optimal charging power, and the maximum power of a single battery includes the maximum charging power; when the power direction of the microgrid is that the energy storage system supplies power to the microgrid, the optimal discharge power curve and the maximum discharge power curve of each of the multiple battery units are invoked; based on the optimal discharge power curve, the maximum discharge power curve, and the remaining charge of each of the multiple battery units, the optimal discharge power and the maximum discharge power of each of the multiple battery units are determined, wherein the optimal power of a single battery includes the optimal discharge power, and the maximum power of a single battery includes the maximum discharge power.

[0009] Optionally, when the power direction of the microgrid is to supply electrical energy to the energy storage system, determining the actual single-cell power of each of the multiple battery units based on the total optimal power, total maximum power, and power of the microgrid includes: when the power of the microgrid is less than the total optimal charging power of the multiple battery units, dividing the power of the microgrid by the total optimal charging power of the multiple battery units to obtain a first ratio, wherein the total optimal charging power of the multiple battery units is the sum of the optimal charging powers of each of the multiple battery units; and multiplying the optimal charging power of each of the multiple battery units by the first ratio to obtain the actual single-cell power of each of the multiple battery units.

[0010] Optionally, if the power of the microgrid is greater than the total optimal charging power of the plurality of battery cells but less than the total maximum charging power of the plurality of battery cells, the power of the microgrid is divided by the total maximum charging power of the plurality of battery cells to obtain a second ratio, wherein the total maximum charging power of the plurality of battery cells is the sum of the maximum charging power of each of the plurality of battery cells; the optimal charging power of each of the plurality of battery cells is multiplied by the second ratio to obtain the actual power of each individual battery cell of the plurality of battery cells; if the power of the microgrid is greater than the total maximum charging power of the plurality of battery cells, the maximum charging power of each of the plurality of battery cells is used as the actual power of each individual battery cell of the plurality of battery cells.

[0011] Optionally, when the power direction of the microgrid is that the energy storage system supplies power to the microgrid, determining the actual power of each individual battery cell based on the total optimal power, total maximum power, and power of the microgrid includes: determining the total remaining power of the multiple battery cells based on their respective remaining power; when the power of the microgrid is less than the total optimal discharge power of the multiple battery cells, dividing the remaining power of each individual battery cell by the total remaining power of the multiple battery cells to obtain a third ratio, wherein the total optimal discharge power of the multiple battery cells is the sum of the optimal discharge powers of each individual battery cell; and multiplying the power of the microgrid by the third ratio to obtain the actual power of each individual battery cell.

[0012] Optionally, if the power of the microgrid is greater than the total optimal discharge power of the plurality of battery cells but less than the total maximum discharge power of the plurality of battery cells, the power of the microgrid is divided by the total maximum discharge power of the plurality of battery cells to obtain a fourth ratio, wherein the total maximum discharge power of the plurality of battery cells is the sum of the maximum discharge power of each of the plurality of battery cells; the optimal discharge power of each of the plurality of battery cells is multiplied by the fourth ratio to obtain the actual power of each individual cell of the plurality of battery cells; if the power of the microgrid is greater than the total maximum discharge power of the plurality of battery cells, the maximum discharge power of each of the plurality of battery cells is used as the actual power of each individual cell of the plurality of battery cells.

[0013] According to another aspect of the present invention, a power control device is also provided, comprising: an acquisition module, configured to acquire the remaining charge of each of a plurality of battery cells in an energy storage system and the power direction and power magnitude of a microgrid connected to the energy storage system, wherein the power direction of the microgrid includes a charging direction or a discharging direction; a first determination module, configured to determine, based on the remaining charge of each of the plurality of battery cells and the power direction of the microgrid, the optimal power of each single cell of the plurality of battery cells matching the power direction of the microgrid, and the maximum power of each single cell of the plurality of battery cells matching the power direction of the microgrid; a second determination module, configured to determine, based on the optimal power of each single cell of the plurality of battery cells and the maximum power of each single cell of the plurality of battery cells, the total optimal power and the total maximum power of the plurality of battery cells; and a third determination module, configured to determine, based on the total optimal power, the total maximum power and the power magnitude of the microgrid, the actual power of each single cell of the plurality of battery cells.

[0014] According to another aspect of the present invention, an energy storage system is also provided, comprising: a microgrid controller, a plurality of energy storage units, and an electricity meter, wherein one end of the electricity meter is connected to the microgrid and the other end is connected to the microgrid controller, and is used to inform the microgrid controller of the power direction and power magnitude of the microgrid; each of the plurality of energy storage units includes a battery cell, a battery management system, and a converter system; the microgrid controller is used to execute the power control method described in any one of the above embodiments to control the actual power of each single battery cell of the plurality of battery cells included in the plurality of energy storage units.

[0015] According to another aspect of the present invention, a non-volatile storage medium is also provided, the non-volatile storage medium including a stored program, wherein, when the program is executed, the device where the non-volatile storage medium is located is controlled to perform any of the power control methods described above.

[0016] According to another aspect of the present invention, a computer device is also provided, the computer device including a memory and a processor, the memory being used to store a program, and the processor being used to run the program stored in the memory, wherein the program, when running, executes any of the power control methods described above.

[0017] In this embodiment of the invention, a method is adopted to reasonably estimate the total optimal power and total maximum power of multiple battery cells in the energy storage system. By determining the actual power of each individual battery cell based on the total optimal power, total maximum power and the power of the microgrid, the actual power of each battery cell in the energy storage system in response to the microgrid's needs is achieved. This achieves the technical effect of improving the intelligent level of power distribution between the battery cells in the energy storage system and the microgrid during charging and discharging, and solves the technical problem of unintelligent power distribution of the battery cells in the energy storage system during charging and discharging. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0019] Figure 1 A hardware structure block diagram of a computer terminal for implementing a power control method is shown.

[0020] Figure 2 This is a schematic flowchart of a power control method provided according to an embodiment of the present invention;

[0021] Figure 3 This is a structural block diagram of an energy storage system provided according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of an energy storage system provided according to an optional embodiment of the present invention;

[0023] Figure 5 This is a flowchart of a battery power control method provided according to an optional embodiment of the present invention;

[0024] Figure 6 This is a structural block diagram of a power control device provided according to an embodiment of the present invention. Detailed Implementation

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] According to an embodiment of the present invention, an embodiment of a power control method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0028] The method embodiment provided in Embodiment 1 of this application can be executed on a mobile terminal, computer terminal, or similar computing device. Figure 1 A hardware block diagram of a computer terminal for implementing a power control method is shown. Figure 1 As shown, the computer terminal 10 may include one or more processors (shown as 102a, 102b, ..., 102n in the figure) (the processor may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.) and a memory 104 for storing data. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of a BUS bus), a network interface, a power supply, and / or a camera. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the aforementioned electronic device. For example, computer terminal 10 may also include... Figure 1 The more or fewer components shown, or having the same Figure 1The different configurations shown.

[0029] It should be noted that the aforementioned one or more processors and / or other data processing circuits are generally referred to herein as "data processing circuits". These data processing circuits may be implemented wholly or partially as software, hardware, firmware, or any other combination thereof. Furthermore, the data processing circuits may be a single, independent processing module, or may be wholly or partially integrated into any other element in the computer terminal 10. As involved in the embodiments of this application, the data processing circuits serve as processor control (e.g., selection of a variable resistor termination path connected to an interface).

[0030] The memory 104 can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the power control method in this embodiment of the invention. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory 104, thereby implementing the power control method of the application described above. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor, and these remote memories can be connected to the computer terminal 10 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0031] The display may be, for example, a touchscreen liquid crystal display (LCD) that allows the user to interact with the user interface of the computer terminal 10.

[0032] Figure 2 This is a schematic flowchart of a power control method provided according to an embodiment of the present invention, such as... Figure 2 As shown, the method includes the following steps:

[0033] Step S202: Obtain the remaining power of each of the multiple battery cells in the energy storage system and the power direction and power magnitude of the microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes the charging direction or the discharging direction.

[0034] In this context, the power direction of a microgrid, if it's the charging direction, indicates that the microgrid needs the energy storage system to charge it, meaning the energy storage system supplies power to the microgrid. Conversely, if the power direction is the discharging direction, it indicates that the microgrid can charge the energy storage system, meaning the microgrid supplies power to the energy storage system. Furthermore, the power magnitude of the microgrid is the power required for charging or discharging. Optionally, a power value encompassing both positive and negative values ​​can be chosen to represent both the power direction and magnitude of the microgrid. For example, P can represent both the power direction and magnitude of the microgrid; when P is greater than 0, it indicates that the microgrid is supplying power to the energy storage system; when P is less than 0, it indicates that the energy storage system is supplying power to the microgrid. The absolute value of P represents the power magnitude of the microgrid.

[0035] Step S204: Based on the remaining power of each of the multiple battery cells and the power direction of the microgrid, determine the optimal power of each single cell of the multiple battery cells that matches the power direction of the microgrid, and determine the maximum power of each single cell of the multiple battery cells that matches the power direction of the microgrid.

[0036] It's important to note that the battery's current state of charge (SOC) affects its performance, specifically its optimal charge / discharge power and maximum charge / discharge power. The optimal charge / discharge power is the power required for the battery to operate stably and normally over a long period, while the maximum charge / discharge power represents the battery's current charge / discharge capacity limit. When environmental conditions permit, it's best to operate the battery at a power level close to its optimal charge / discharge power.

[0037] As an optional embodiment, determining the optimal single-cell power of each of the multiple battery cells that matches the power direction of the microgrid, and determining the maximum single-cell power of each of the multiple battery cells that matches the power direction of the microgrid, based on the remaining charge of each of the multiple battery cells and the power direction of the microgrid, may include the following steps:

[0038] When the power direction of the microgrid is to supply power to the energy storage system, the optimal charging power curves and maximum charging power curves of multiple battery cells are retrieved. Based on these curves and the remaining charge of each battery cell, the optimal charging power and maximum charging power of each battery cell are determined. Here, the optimal power of a single battery cell includes the optimal charging power, and the maximum power of a single battery cell includes the maximum charging power. Similarly, when the power direction of the microgrid is to supply power to the energy storage system, the optimal discharging power curves and maximum discharging power curves of multiple battery cells are retrieved. Based on these curves and the remaining charge of each battery cell, the optimal discharging power and maximum discharging power of each battery cell are determined. Here, the optimal power of a single battery cell includes the optimal discharging power, and the maximum power of a single battery cell includes the maximum discharging power.

[0039] It should be noted that the optimal charging power curve, maximum charging power curve, optimal discharging power curve, and maximum discharging power curve can be curve data pre-built into the microgrid controller. These curves can be obtained by conducting actual charge and discharge tests on multiple battery cells in the energy storage system, thus reflecting the individual electrical characteristics of each battery cell in the energy storage system. Optionally, the horizontal axis of the above curves can be the current SOC of the battery. Therefore, based on the current SOC of each battery cell, the current optimal charging power, maximum charging power, optimal discharging power, and maximum discharging power of each battery cell can be determined.

[0040] Step S206: Determine the total optimal power and total maximum power of the multiple battery cells based on the individual optimal power and the individual maximum power of each battery cell.

[0041] Optionally, the optimal power of a single battery may include the optimal discharge power and optimal charging power of the battery cell; the maximum power of a single battery may include the maximum discharge power and optimal discharge power of the battery cell.

[0042] Step S208: Determine the actual power of each individual cell in the multiple battery cells based on the total optimal power, total maximum power and power of the multiple battery cells and the power of the microgrid.

[0043] Optionally, when the power direction of the microgrid is to transmit electrical energy from the microgrid to the energy storage system, step S208 can be implemented as follows: when the power of the microgrid is less than the total optimal charging power of the multiple battery units, the power of the microgrid is divided by the total optimal charging power of the multiple battery units to obtain a first ratio, wherein the total optimal charging power of the multiple battery units is the sum of the optimal charging power of each of the multiple battery units; the optimal charging power of each of the multiple battery units is multiplied by the first ratio to obtain the actual power of each single battery of the multiple battery units.

[0044] The optimal charging power of each of the multiple battery cells can be expressed as p. i The subscript i represents the serial number of each battery cell in the energy storage system, and the total optimal charging power of the multiple battery cells can be represented by p. 总 express, n represents the total number of battery cells, and P represents the power of the microgrid. Therefore, the first ratio is P / p. 总 Then, the actual power of each individual battery cell in the multiple battery units can be expressed as (p i *P / p 总 Furthermore, the actual power of a single battery is the actual charging power of each battery cell.

[0045] As an optional embodiment, when the power of the microgrid is greater than the total optimal charging power of the multiple battery cells but less than the total maximum charging power of the multiple battery cells, the power of the microgrid is divided by the total maximum charging power of the multiple battery cells to obtain a second ratio, wherein the total maximum charging power of the multiple battery cells is the sum of the maximum charging power of each of the multiple battery cells; the optimal charging power of each of the multiple battery cells is multiplied by the second ratio to obtain the actual power of each individual battery cell; when the power of the microgrid is greater than the total maximum charging power of the multiple battery cells, the maximum charging power of each of the multiple battery cells is used as the actual power of each individual battery cell.

[0046] The second ratio can be expressed as P / pmax. 总 pmax 总 This indicates the total maximum charging power of multiple battery cells. pmax i This represents the maximum charging power of each of the multiple battery cells. Further, the actual power of a single battery obtained by multiplying the optimal charging power of each of the multiple battery cells by a second ratio can be expressed as (pi*P / pmax). 总 When the microgrid power exceeds the total maximum charging power, the pmax of each of the multiple battery cells is... i This refers to the actual power of a single battery.

[0047] As an optional embodiment, when the power direction of the microgrid is that the energy storage system supplies power to the microgrid, the actual power of each individual battery cell in the multiple battery cells can be determined based on the total optimal power, total maximum power, and power of the microgrid. This can be achieved through the following steps: determining the total remaining power of the multiple battery cells based on their respective remaining power; if the power of the microgrid is less than the total optimal discharge power of the multiple battery cells, dividing the remaining power of each individual battery cell by the total remaining power of the multiple battery cells to obtain a third ratio, where the total optimal discharge power of the multiple battery cells is the sum of the optimal discharge powers of each individual battery cell; and multiplying the power of the microgrid by the third ratio to obtain the actual power of each individual battery cell.

[0048] The remaining charge of each of the multiple battery cells can be expressed as SOC (State of Charge). i Where the subscript i represents the serial number of the battery cell, and the total remaining capacity of multiple battery cells can be expressed as: At this point, the total optimal discharge power of the multiple battery cells can be expressed as p' 总 The optimal discharge power of each of the multiple battery cells is expressed as p. i ',and The third proportion can be expressed as SOC. i / SOC 总 Since the remaining charge of each battery cell varies, the third ratio can include a set of ratios, the number of which is equal to the number of battery cells n in the energy storage system. Multiplying the power P of the microgrid by the third ratio yields the actual discharge power of each individual battery cell.

[0049] As an optional embodiment, when the power of the microgrid is greater than the total optimal discharge power of the multiple battery cells but less than the total maximum discharge power of the multiple battery cells, the power of the microgrid is divided by the total maximum discharge power of the multiple battery cells to obtain a fourth ratio, wherein the total maximum discharge power of the multiple battery cells is the sum of the maximum discharge power of each of the multiple battery cells; the optimal discharge power of each of the multiple battery cells is multiplied by the fourth ratio to obtain the actual power of each individual cell of the multiple battery cells; when the power of the microgrid is greater than the total maximum discharge power of the multiple battery cells, the maximum discharge power of each of the multiple battery cells is taken as the actual power of each individual cell of the multiple battery cells.

[0050] The total maximum discharge power of multiple battery cells can be expressed as pmax' 总 The maximum discharge power of each of the multiple battery cells can be expressed as pmax' i ,and At this point, the fourth ratio can be expressed as P / pmax'总 The actual power of each individual battery cell can be expressed as (p i '*P / pmax' 总 When P is greater than pmax' i In the case of pmax' i This refers to the actual discharge power of each individual cell in multiple battery units.

[0051] Through the above steps, by reasonably estimating the total optimal power and total maximum power of multiple battery cells in the energy storage system, and by determining the actual power of each individual battery cell based on the total optimal power, total maximum power, and the power of the microgrid, the actual power of each battery cell in the energy storage system in response to the microgrid's demands is achieved. This achieves the technical effect of improving the intelligent level of power distribution between the battery cells in the energy storage system and the microgrid during charging and discharging, and solves the technical problem of unintelligent power distribution during charging and discharging of the battery cells in the energy storage system. The above method and steps can be applied to microgrid controllers.

[0052] Figure 3 This is a structural block diagram of an energy storage system provided according to an embodiment of the present invention, such as... Figure 3 As shown, the energy storage system 30 includes: a microgrid controller 31, multiple energy storage units 32, and an electricity meter 33. One end of the electricity meter is connected to the microgrid, and the other end is connected to the microgrid controller. The meter is used to inform the microgrid controller of the power direction and power magnitude of the microgrid. Each of the multiple energy storage units includes a battery cell, a battery management system, and a converter system. The microgrid controller is used to execute any of the above power control methods to control the actual power of each individual battery cell in the multiple energy storage units.

[0053] Figure 4 This is a schematic diagram of the structure of an energy storage system provided by an optional embodiment of the present invention, such as... Figure 4As shown, each energy storage system manages the charging and discharging of energy in the energy storage container through a microgrid controller. The microgrid controller 31 can be connected to the load and the power grid via a meter 33. The load typically requires power from the energy storage container, and the power grid can transmit power to the energy storage container. There can be n energy storage containers, each containing a battery management system (BMS) and a power converter (PCS). The BMS is a secondary device in the energy storage container, used to collect the electrical state of the battery cells, such as the remaining charge, and transmit this remaining charge to the microgrid controller 31. The PCS is a primary device in the energy storage container, used to control the charging and discharging state of the battery cells. Therefore, the microgrid controller 31 can send control signals to the PCS to control the actual power of each battery cell in each energy storage container. Multiple energy storage containers represent an optional embodiment of multiple energy storage units 32.

[0054] Optionally, the microgrid controller 31 can employ an A8-ARM processor. Data transmission between the microgrid controller 31 and the PCS can utilize the Moldbus-TCP protocol, and between the microgrid controller 31 and the BMS can utilize the IEC104 protocol. A circuit breaker is installed between the PCS and the power grid, and the MC is electrically connected to the circuit breaker. When the MC detects an abnormality in the battery cell through the BMS, it can immediately issue a disconnect command to the circuit breaker, thereby directly cutting off the battery cell and issuing a stop-charging command to the PCS, thus protecting the PCS.

[0055] Figure 5 This is a flowchart of a battery power control method provided by an optional embodiment of the present invention, such as... Figure 5 As shown, the method may include the following steps:

[0056] Step S1: Start the microgrid controller (MC). The MC collects the SOC status of each battery cell through the BMS of each battery cell and numbers them sequentially as SOC. i The MC collects the current microgrid status through the meter, that is, the charging power required or the excess power of the microgrid, i.e., the microgrid power P, so as to determine whether the energy storage system should discharge or charge. The positive or negative value of P and the relationship between charging and discharging can be temporarily defined as needed.

[0057] Step S2: If P>0, then it is determined that the energy storage system is charging. MC determines the charging time based on the SOC of each battery cell. i Based on the situation, determine the optimal charging power p for each battery cell. i and maximum charging power pmax i And calculate the total optimal charging power. Total maximum charging power If p 总If the total optimal charging power is greater than the microgrid power P, then the charging power of each energy storage sub-unit is (pi*P / p). 总 This ensures that while meeting the power requirements of the microgrid, the actual charging power of each battery cell can approach the optimal charging power p. i .

[0058] Step S3: In pmax 总 >P>P 总 In this case, the actual charging power of each energy storage sub-unit can be (p i *P / pmax 总 This ensures that while meeting the power requirements of the microgrid, the charging power of each battery cell can approach the optimal charging power p. i If P > pmax 总 Then the actual charging power of each energy storage sub-unit is p = pmax i At this point, each battery cell exerts its maximum power input capability under the current SOC state.

[0059] Step S4: If P < 0, it is determined that the energy storage system is discharging. MC is based on the SOC of each battery cell. i Based on the power curve, determine the optimal discharge power p of each battery cell. i 'Maximum discharge power pmax' i And calculate the total optimal discharge power p' of each battery cell. 总 Total maximum discharge power and the total remaining capacity of each battery cell

[0060] If p' 总 If the total optimal discharge power is greater than the microgrid power P, then the output power of each battery cell is P*(SOC). i / SOC 总 This ensures that while meeting the power requirements of the microgrid, the discharge power of each battery cell is allocated according to its SOC (State of Charge). That is, battery cells with high SOC discharge more and battery cells with low SOC discharge less, ensuring that each battery cell can be discharged at the same time and avoiding sudden power changes.

[0061] Step S5: pmax' 总 >P>p' 总 Then the output power of each energy storage sub-unit is (p i '*P / pmax' 总 This ensures that while meeting the power requirements of the microgrid, the discharge power of each battery cell can approach the optimal discharge power p. i If P is greater than pmax' 总Then the actual discharge power of each battery cell is pmax' i At this point, each battery cell exerts its maximum power output capability under the current SOC state.

[0062] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0063] Through the above description of the embodiments, those skilled in the art can clearly understand that the power control method according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0064] According to embodiments of the present invention, a power control device for implementing the above-described power control method is also provided. Figure 6 This is a structural block diagram of a power control device provided according to an embodiment of the present invention, such as... Figure 6 As shown, the power control device includes: an acquisition module 62, a first determination module 64, a second determination module 66, and a third determination module 68. The power control device will be described below.

[0065] The acquisition module 62 is used to acquire the remaining power of each of the multiple battery cells in the energy storage system and the power direction and power of the microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes the charging direction or the discharging direction.

[0066] The first determining module 64, connected to the aforementioned obtaining module 62, is used to determine the optimal single-cell power of each of the multiple battery cells that matches the power direction of the microgrid, and to determine the maximum single-cell power of each of the multiple battery cells that matches the power direction of the microgrid, based on the remaining power of each of the multiple battery cells and the power direction of the microgrid.

[0067] The second determining module 66 is connected to the first determining module 64 and is used to determine the total optimal power and total maximum power of the multiple battery cells based on the optimal power of each individual battery cell and the maximum power of each individual battery cell.

[0068] The third determining module 68, connected to the second determining module 66, is used to determine the actual power of each individual cell in the multiple battery cells based on the total optimal power, total maximum power, and power of the microgrid.

[0069] It should be noted that the aforementioned acquisition module 62, first determination module 64, second determination module 66, and third determination module 68 correspond to steps S202 to S208 in the embodiments. Multiple modules implement the same instances and application scenarios as their corresponding steps, but are not limited to the content disclosed in the above embodiments. It should also be noted that the aforementioned modules, as part of the device, can run on the computer terminal 10 provided in the embodiments.

[0070] Embodiments of the present invention may provide a computer device. Optionally, in this embodiment, the computer device may be located in at least one of a plurality of network devices in a computer network. The computer device includes a memory and a processor.

[0071] The memory can be used to store software programs and modules, such as the program instructions / modules corresponding to the power control method and device in this embodiment of the invention. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory, thereby realizing the aforementioned power control method. The memory may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to a computer terminal via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0072] The processor can access information and applications stored in the memory via a transmission device to perform the following steps: obtaining the remaining charge of each of the multiple battery cells in the energy storage system and the power direction and power magnitude of the microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes the charging direction or the discharging direction; determining the optimal power of each individual battery cell of the multiple battery cells that matches the power direction of the microgrid, and determining the maximum power of each individual battery cell of the multiple battery cells that matches the power direction of the microgrid, based on the remaining charge of each of the multiple battery cells and the power direction of the microgrid; determining the total optimal power and total maximum power of the multiple battery cells based on the optimal power and the maximum power of each individual battery cell of the multiple battery cells; and determining the actual power of each individual battery cell of the multiple battery cells based on the total optimal power, the total maximum power, and the power magnitude of the microgrid.

[0073] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing the hardware related to the terminal device. The program can be stored in a non-volatile storage medium, which may include: flash drive, read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc.

[0074] Embodiments of the present invention also provide a non-volatile storage medium. Optionally, in this embodiment, the aforementioned non-volatile storage medium can be used to store the program code executed by the power control method provided in the above embodiments.

[0075] Optionally, in this embodiment, the non-volatile storage medium may be located in any computer terminal in a group of computer terminals in a computer network, or in any mobile terminal in a group of mobile terminals.

[0076] Optionally, in this embodiment, the non-volatile storage medium is configured to store program code for performing the following steps: obtaining the remaining charge of each of the multiple battery cells in the energy storage system and the power direction and power magnitude of the microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes a charging direction or a discharging direction; determining the optimal power of each individual battery cell of the multiple battery cells that matches the power direction of the microgrid, and determining the maximum power of each individual battery cell of the multiple battery cells that matches the power direction of the microgrid, based on the remaining charge of each of the multiple battery cells and the power direction of the microgrid; determining the total optimal power and total maximum power of the multiple battery cells based on the optimal power and the maximum power of each individual battery cell of the multiple battery cells; and determining the actual power of each individual battery cell of the multiple battery cells based on the total optimal power, the total maximum power, and the power magnitude of the microgrid.

[0077] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0078] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0079] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between units or modules may be electrical or other forms.

[0080] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0081] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0082] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a non-volatile storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0083] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A power control method, characterized in that, include: The remaining power of each of the multiple battery cells in the energy storage system and the power direction and power magnitude of the microgrid to which the energy storage system is connected are obtained, wherein the power direction of the microgrid includes the charging direction or the discharging direction. Based on the remaining power of each of the plurality of battery cells and the power direction of the microgrid, determine the optimal single-cell power of each of the plurality of battery cells that matches the power direction of the microgrid, and determine the maximum single-cell power of each of the plurality of battery cells that matches the power direction of the microgrid. The total optimal power and total maximum power of the multiple battery cells are determined based on the individual optimal power and the individual maximum power of each battery cell. Based on the total optimal power, total maximum power of the multiple battery cells and the power of the microgrid, the actual power of each individual cell in the multiple battery cells is determined. Where the power direction of the microgrid is to supply power to the energy storage system, determining the actual power of each individual battery cell based on the total optimal power, total maximum power, and power of the microgrid includes: when the power of the microgrid is less than the total optimal charging power of the multiple battery cells, dividing the power of the microgrid by the total optimal charging power of the multiple battery cells to obtain a first ratio, wherein the total optimal charging power of the multiple battery cells is the sum of the optimal charging powers of each of the multiple battery cells; and multiplying the optimal charging power of each of the multiple battery cells by the first ratio to obtain the actual power of each individual battery cell.

2. The method according to claim 1, characterized in that, The step of determining the optimal single-cell power of each of the plurality of battery cells matching the power direction of the microgrid, and determining the maximum single-cell power of each of the plurality of battery cells matching the power direction of the microgrid, based on the remaining charge of each of the plurality of battery cells and the power direction of the microgrid, includes: When the power direction of the microgrid is to supply electrical energy to the energy storage system, the optimal charging power curve and the maximum charging power curve of each of the multiple battery cells are invoked. Based on the optimal charging power curve, the maximum charging power curve, and the remaining capacity of each of the multiple battery cells, the optimal charging power and the maximum charging power of each of the multiple battery cells are determined, wherein the optimal power of a single battery includes the optimal charging power, and the maximum power of a single battery includes the maximum charging power. When the power direction of the microgrid is that the energy storage system supplies power to the microgrid, the optimal discharge power curve and the maximum discharge power curve of each of the multiple battery cells are invoked. Based on the optimal discharge power curve, the maximum discharge power curve, and the remaining charge of each of the plurality of battery cells, the optimal discharge power and the maximum discharge power of each of the plurality of battery cells are determined, wherein the optimal power of a single battery includes the optimal discharge power, and the maximum power of a single battery includes the maximum discharge power.

3. The method according to claim 1, characterized in that, When the power of the microgrid is greater than the total optimal charging power of the multiple battery cells but less than the total maximum charging power of the multiple battery cells, the power of the microgrid is divided by the total maximum charging power of the multiple battery cells to obtain a second ratio, wherein the total maximum charging power of the multiple battery cells is the sum of the maximum charging power of each of the multiple battery cells; Multiply the optimal charging power of each of the plurality of battery cells by the second ratio to obtain the actual single-cell power of each of the plurality of battery cells. If the power of the microgrid is greater than the total maximum charging power of the multiple battery cells, the maximum charging power of each of the multiple battery cells shall be taken as the actual power of each individual battery cell.

4. The method according to claim 2, characterized in that, When the power direction of the microgrid is that the energy storage system supplies power to the microgrid, determining the actual single-cell power of each of the multiple battery cells based on the total optimal power, total maximum power, and power level of the microgrid includes: The total remaining capacity of the multiple battery cells is determined based on the remaining capacity of each individual battery cell. When the power of the microgrid is less than the total optimal discharge power of the multiple battery cells, the remaining power of each of the multiple battery cells is divided by the total remaining power of the multiple battery cells to obtain a third ratio, wherein the total optimal discharge power of the multiple battery cells is the sum of the optimal discharge power of each of the multiple battery cells; Multiplying the power of the microgrid by the third ratio yields the actual power of each individual battery cell in the plurality of battery units.

5. The method according to claim 4, characterized in that, When the power of the microgrid is greater than the total optimal discharge power of the multiple battery cells but less than the total maximum discharge power of the multiple battery cells, the power of the microgrid is divided by the total maximum discharge power of the multiple battery cells to obtain a fourth ratio, wherein the total maximum discharge power of the multiple battery cells is the sum of the maximum discharge power of each of the multiple battery cells. Multiply the optimal discharge power of each of the plurality of battery cells by the fourth ratio to obtain the actual single-cell power of each of the plurality of battery cells. If the power of the microgrid is greater than the total maximum discharge power of the multiple battery cells, the maximum discharge power of each of the multiple battery cells shall be taken as the actual power of each individual cell of the multiple battery cells.

6. A power control device, characterized in that, include: The acquisition module is used to acquire the remaining power of each of the multiple battery cells in the energy storage system and the power direction and power magnitude of the microgrid to which the energy storage system is connected, wherein the power direction of the microgrid includes the charging direction or the discharging direction. The first determining module is used to determine the optimal single-cell power of each of the plurality of battery cells that matches the power direction of the microgrid, based on the remaining power of each of the plurality of battery cells and the power direction of the microgrid, and to determine the maximum single-cell power of each of the plurality of battery cells that matches the power direction of the microgrid. The second determining module is used to determine the total optimal power and total maximum power of the multiple battery cells based on the individual optimal power of each battery cell and the individual maximum power of each battery cell. The third determining module is used to determine the actual power of each individual cell of the multiple battery cells based on the total optimal power, total maximum power and power of the multiple battery cells and the power of the microgrid. Wherein, when the power direction of the microgrid is to transmit electrical energy from the microgrid to the energy storage system, the third determining module is further configured to, when the power of the microgrid is less than the total optimal charging power of the plurality of battery units, divide the power of the microgrid by the total optimal charging power of the plurality of battery units to obtain a first ratio, wherein the total optimal charging power of the plurality of battery units is the sum of the optimal charging power of each of the plurality of battery units; and multiply the optimal charging power of each of the plurality of battery units by the first ratio to obtain the actual power of each individual battery cell of the plurality of battery units.

7. An energy storage system, characterized in that, include: The system comprises a microgrid controller, multiple energy storage units, and an electricity meter, wherein one end of the electricity meter is connected to the microgrid and the other end is connected to the microgrid controller, and is used to inform the microgrid controller of the power direction and power magnitude of the microgrid; each of the multiple energy storage units includes a battery cell, a battery management system, and a converter system; the microgrid controller is used to execute the power control method according to any one of claims 1 to 5 to control the actual power of each individual battery cell of the multiple energy storage units.

8. A non-volatile storage medium, characterized in that, The non-volatile storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the non-volatile storage medium to perform the power control method according to any one of claims 1 to 5.

9. A computer device, characterized in that, The computer device includes a memory and a processor, the memory being used to store a program, and the processor being used to run the program stored in the memory, wherein the program, when running, executes the power control method according to any one of claims 1 to 5.

Images