A discharge method for a parallel energy storage device, an energy storage inverter, and an energy storage system.

Abstract

This invention relates to a discharge method, energy storage device, and energy storage system for parallel energy storage devices. The method first supplies power to the load using the first N battery packs with higher charge. When the remaining capacity of at least one of the first N battery packs is equal to the remaining capacity of the (N+1)th battery pack, the (N+1)th battery pack is then added in parallel, and so on, until M battery packs are added. Therefore, compared to a discharge method that directly puts M battery packs into use, the discharge method of this application ensures that the remaining capacity of each battery pack is nearly equal during the discharge process, thus balancing the remaining capacity of each battery pack and achieving a better balanced discharge effect. If the output power of the load is increased, the discharge time of the battery packs can be extended, improving the discharge efficiency of the battery packs. Furthermore, since each battery pack can be driven independently, when the user does not need to use parallel battery pack technology, the charge balance of each battery pack can be guaranteed, making it convenient for the user.

Description

Technical Field

[0001] This invention relates to the field of energy storage power supply, and in particular to a discharge method for parallel energy storage devices, an energy storage inverter, and an energy storage system. Background Technology

[0002] With the improvement of living standards, more and more people are keen on outdoor activities, and energy storage power supplies have become increasingly popular in recent years. User demands are also gradually increasing; for example, users want energy storage devices to be able to power high-power equipment, such as 3000W or 4000W, while typically each battery pack has a maximum output power of, for example, 1500W. A single battery pack cannot meet the power demands of high-power loads.

[0003] To power high-power devices, current methods typically involve connecting multiple battery packs to a main unit using parallel charging technology. The output power is determined by the percentage of remaining charge in each battery pack. For example, if four battery packs are connected to a main unit, each with a maximum output power of 1500W and remaining charge percentages of 80%, 60%, 40%, and 20%, and a 3000W load needs to be powered, the output power of the battery packs would be 1200W, 900W, 600W, and 300W respectively. Throughout the discharge phase, the energy storage device maintains a 4:3:2:1 ratio of remaining charge in the multiple battery packs.

[0004] As the battery packs discharge for a period of time, the low-charge battery packs may run out of power prematurely, while the high-charge battery packs may still have some charge remaining. If the user increases the load power demand at this point, for example, requiring a 4000W load, the power output will continue to be proportional to the remaining charge. The battery pack with the largest remaining charge will then need to output 1600W, exceeding its rated power (maximum output power). Therefore, the extra 100W must be distributed among the other three battery packs. The low-charge battery packs, due to depletion or insufficient remaining charge, may not be able to meet this 100W demand, thus failing to provide normal power to the large load and reducing the battery pack's discharge time. Summary of the Invention

[0005] The embodiments of the present invention at least partially solve one of the above-mentioned technical problems. To this end, the present invention provides a discharge method for parallel energy storage devices, an energy storage inverter, and an energy storage system, which can make the remaining power of each battery pack balanced during the discharge process, and thus extend the battery discharge time when the load output power is increased.

[0006] In a first aspect, embodiments of the present invention provide a discharge method for a parallel energy storage device, the parallel energy storage device comprising M parallel battery packs, wherein M ≥ 2, the method comprising:

[0007] Obtain the remaining capacity and maximum output power of each of the battery packs;

[0008] The battery packs are sorted from highest to lowest based on their remaining capacity to obtain a sorting table;

[0009] Obtain the output power of the load connected to the parallel energy storage device;

[0010] The number N of battery packs supplying power to the load is determined based on the load's output power, the maximum output power, and the sorting table.

[0011] Based on the remaining capacity of the first N+1 battery packs in the sorting table and the output power of the load, determine the allocated power of the first N battery packs in the sorting table, where N+1≤M, and the allocated power is the output power required by the first N battery packs;

[0012] The load is powered according to the allocated power of the first N battery packs and the maximum output power;

[0013] When the remaining capacity of at least one of the N battery packs is equal to the remaining capacity of the (N+1)th battery pack, the (N+1)th battery pack is incorporated, so that the first N+1 battery packs supply power to the load according to the allocated power of the battery packs and the maximum output power, where N+1≤M; and so on, until M battery packs are incorporated.

[0014] In some embodiments, determining the number N of battery packs supplying power to the load based on the output power of the load, the maximum output power, and the sorting table includes:

[0015] If each of the maximum output powers is the same, then the number N of the battery packs supplying power to the load is determined by the following formula:

[0016] N = int(P / P) 包max );

[0017] Where int(...) represents rounding up, and P is the output power of the load. 包max This refers to the maximum output power.

[0018] In some embodiments, determining the number N of battery packs supplying power to the load based on the output power of the load, the maximum output power, and the sorting table includes:

[0019] When the maximum output power is different, if the difference between the first sum and the output power of the load is less than or equal to a preset threshold, then the number of battery packs supplying power to the load is determined to be N, wherein the first sum is the sum of the maximum output power of the first N battery packs in the sorting table.

[0020] In some embodiments, determining the allocated power of the first N battery packs in the sorting table based on the remaining capacity of the first N+1 battery packs and the output power of the load includes:

[0021] Obtain the first difference between the remaining capacity of the first N battery packs and the remaining capacity of the (N+1)th battery pack;

[0022] Based on the difference ratio of the first difference and the output power of the load, the allocated power of the first N battery packs in the sorting table is determined.

[0023] In some embodiments, supplying power to the load based on the allocated power of the first N battery packs and the maximum output power includes:

[0024] If the allocated power is less than or equal to the corresponding maximum output power, then the battery pack is controlled to supply power to the load according to the allocated power.

[0025] In some embodiments, supplying power to the load based on the allocated power of the first N battery packs and the maximum output power includes:

[0026] If the allocated power is greater than the corresponding maximum output power, then the allocated power of the corresponding battery pack is determined as the corresponding maximum output power, and a second difference between the allocated power and the maximum output power is obtained;

[0027] According to the aforementioned difference ratio, the second difference is allocated to the first N battery packs that do not exceed the maximum output power, to obtain the new allocated power;

[0028] Control the battery pack to supply power to the load according to the new power allocation.

[0029] In some embodiments, the method further includes:

[0030] When the output power of the load connected to the parallel energy storage device changes, the process returns to the step of determining the number N of battery packs supplying power to the load based on the output power of the load, the maximum output power, and the sorting table.

[0031] In a second aspect, embodiments of the present invention provide a controller, the controller including at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the discharge method of the parallel energy storage device as described above.

[0032] Thirdly, embodiments of the present invention provide an energy storage inverter, the energy storage inverter comprising: a parallel energy storage module and an inverter module;

[0033] The parallel energy storage module includes M parallel battery packs, where M ≥ 2;

[0034] The inverter module includes M parallel DC / DC conversion modules, an inverter module, and a controller as described above. The battery pack is connected to the input terminals of the DC / DC conversion modules one by one. The output terminals of the DC / DC conversion modules are first connected in parallel and then connected to the input terminals of the inverter modules. The battery pack, the DC / DC conversion modules, and the inverter modules are all connected to the controller.

[0035] Fourthly, embodiments of the present invention provide an energy storage system, wherein the energy storage system pre-stores multiple discharge modes and multiple control commands, wherein at least one of the discharge modes adopts the discharge method of the parallel energy storage device as described above, and each control command corresponds to a discharge mode;

[0036] The energy storage system is used to receive the control command, obtain the corresponding discharge mode according to the control command, and use the corresponding discharge mode to supply power to the load.

[0037] Compared with the prior art, the present invention has at least the following beneficial effects: The discharge method of the parallel energy storage device in the present invention is applied to a parallel energy storage device, which includes M parallel battery packs. The discharge method first obtains the remaining capacity and maximum output power of each battery pack, sorts the battery packs from high to low according to the remaining capacity of each battery pack to obtain a sorting table, then obtains the output power of the load connected to the parallel energy storage device, and then determines the number N of battery packs to supply power to the load according to the output power of the load, the maximum output power and the sorting table. Then, according to the allocated power and maximum output power of the first N battery packs, power is supplied to the load. When the remaining capacity of at least one of the first N battery packs is equal to the remaining capacity of the (N+1)th battery pack, the (N+1)th battery pack is added, so that the first (N+1)th battery packs supply power to the load according to the allocated power and maximum output power of the battery packs, and so on, until all M battery packs are added.

[0038] In summary, this method first supplies power to the load using the first N battery packs with higher charge. When the remaining capacity of at least one of the first N battery packs is equal to that of the (N+1)th battery pack, the (N+1)th battery pack is then added, and this process continues until all M battery packs are added. Therefore, compared to a discharge method that directly uses all M battery packs, this method ensures that the remaining capacity of each battery pack is nearly equal during discharge, balancing the remaining capacity of each pack and achieving a better balanced discharge effect. Increasing the output power of the load can extend the discharge time of the battery packs and improve their discharge efficiency. Furthermore, since each battery pack can be driven independently, when the user does not need to use parallel charging technology, it ensures balanced charge across all battery packs, making it convenient for the user. Attached Figure Description

[0039] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0040] Figure 1 This is a schematic diagram of the structure of an energy storage inverter provided in an embodiment of the present invention;

[0041] Figure 2 This is a schematic flowchart of a discharge method for a parallel energy storage device provided in an embodiment of the present invention;

[0042] Figure 3 yes Figure 2 A flowchart illustrating step S25;

[0043] Figure 4 yes Figure 2 A flowchart illustrating step S26;

[0044] Figure 5 This is a schematic diagram of the discharge device of a parallel energy storage device provided in an embodiment of the present invention;

[0045] Figure 6 This is a schematic diagram of a controller hardware structure provided in an embodiment of the present invention;

[0046] Figure 7 This is a schematic diagram of the working process of an energy storage system provided in an embodiment of the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0048] It should be noted that, unless otherwise specified, the various features in the embodiments of this invention can be combined with each other, all of which are within the protection scope of this invention. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the device or the order in the flowchart. Moreover, the terms "first," "second," and "third" used in this invention do not limit the data or execution order, but only distinguish identical or similar items with essentially the same function and effect.

[0049] Please see Figure 1 , Figure 1 This is an energy storage inverter provided in an embodiment of the present invention, such as... Figure 1 As shown, the energy storage inverter 100 includes a parallel energy storage module 10 and an inverter module 20. The parallel energy storage module 10 includes M parallel battery packs, where M ≥ 2, meaning the parallel energy storage module 10 includes at least two parallel battery packs. The inverter module 20 includes M parallel DC / DC converter modules 21, inverter modules 22, and a controller 23. The battery packs are connected one-to-one with the input terminals of the DC / DC converter modules 21. The output terminals of the DC / DC converter modules 21 are first connected in parallel and then connected to the input terminals of the inverter modules 22. The battery packs, DC / DC converter modules 21, and inverter modules 22 are all connected to the controller 23.

[0050] The number of DC / DC converter modules 21 is the same as the number of battery packs, with one module for each battery pack. Each DC / DC converter module 21 boosts the voltage output from the battery pack, then rectifies the boosted voltage, and finally transmits the rectified voltage to the inverter module 22. The operating state of each DC / DC converter module 21 is controlled in real-time by the controller 23. For example, the controller 23 controls the operating state of the DC / DC converter module 21 and its internal circuitry to achieve the corresponding boost conversion based on the voltage, current, temperature, and remaining capacity information sent by the battery pack.

[0051] The outputs of DC / DC converter module 21 are first connected in parallel to aggregate the electrical energy, and then the aggregated electrical energy is transmitted to inverter module 22. Inverter module 22 contains an inverter circuit, which can be a full-bridge inverter circuit, used to perform full-bridge inversion on the aggregated electrical energy. Inverter module 22 may also include some filtering circuits to filter the aggregated electrical energy or the inverted electrical energy, thereby obtaining AC power that meets the required quality. Inverter module 22 is also connected to controller 23, which performs PWM control on the high-frequency power MOS in the full-bridge inverter circuit to achieve real-time control of the full-bridge inverter circuit by controller 23.

[0052] The controller 23 can be located inside the energy storage inverter 100 or it can be an external controller. The controller 23 serves as the control core of the energy storage inverter 100 and is used to control the working state of the DC / DC conversion module 21 and the inverter module 22, as well as control the charging and discharging modes and methods of the M battery packs, such as the discharge method of a parallel energy storage device provided in the following embodiment.

[0053] In some embodiments, controller 23 may be a general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), microcontroller, ARM (Acorn RISC Machine) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of these components. Additionally, controller 23 may also be any conventional processor, controller, microcontroller, or state machine. Controller 23 may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP, and / or any other such configuration.

[0054] Please refer to the figure. Figure 2 , Figure 2 This is a schematic flowchart of a discharge method for a parallel energy storage device provided in an embodiment of the present invention. The parallel energy storage device includes M battery packs connected in parallel, wherein M ≥ 2, as shown below. Figure 2 As shown, the discharge method of the parallel energy storage device includes:

[0055] S21. Obtain the remaining capacity and maximum output power of each of the battery packs;

[0056] A battery pack refers to a battery pack connected to a host device that can collectively output power to supply power to a load. For example, the number of battery packs is M, where M≥2 is preferred, M≥3 or more, meaning that a parallel energy storage device includes at least two battery packs.

[0057] The remaining capacity of a battery pack refers to the remaining charge of the battery pack, which is the remaining state of charge (SOC). The maximum output power of the battery pack is the rated output power. During battery pack discharge, the controller can directly obtain the remaining capacity and maximum output power of each battery pack, and can also obtain these parameters from the battery management system (BMS).

[0058] S22. Sort the battery packs from high to low according to their remaining capacity to obtain a sorting table;

[0059] S23. Obtain the output power of the load connected to the parallel energy storage device;

[0060] The load is electrically connected to the parallel energy storage device. The output power of the load can be obtained in real time by detecting the power P of the load. Alternatively, the output power of the load can be pre-stored in the controller or BMS system, and the output power of the load can be obtained when it is necessary to discharge the load.

[0061] S24. Determine the number N of battery packs that supply power to the load based on the output power of the load, the maximum output power, and the sorting table;

[0062] When supplying power to a load, not all M battery packs are used for discharging. Instead, the number N of battery packs used to supply power to the load is determined by combining the load's output power, the maximum output power of the battery packs, and the sorting table, where N ≤ M.

[0063] Specifically, in some embodiments, if each of the maximum output powers is the same, the number N of the battery packs supplying power to the load is determined by the following formula:

[0064] N = int(P / P) 包max (1)

[0065] Where int(...) represents rounding up, and P is the output power of the load. 包max This refers to the maximum output power.

[0066] For example, P = 2000W, P 包max =1500W, then N=2, meaning that the two battery packs power the load.

[0067] In some embodiments, if the maximum output power of the battery packs are different, if the difference between the first sum and the output power of the load is less than or equal to a preset threshold, then the number of battery packs supplying power to the load is determined to be N, wherein the first sum is the sum of the maximum output power of the first N battery packs in the sorting table.

[0068] That is, the difference between the sum of the maximum output power of the first N battery packs in the sorting table and the output power of the load is less than or equal to a preset threshold, wherein the preset threshold can be set as needed. The smaller the difference between the first sum and the output power of the load, the better; preferably, the difference between the first sum and the output power of the load is zero.

[0069] S25. Based on the remaining capacity of the first N+1 battery packs in the sorting table and the output power of the load, determine the allocated power of the first N battery packs in the sorting table, where N+1≤M, and the allocated power is the output power required by the first N battery packs.

[0070] After determining the number of battery packs to power the load, the required output power of each battery pack is then determined, i.e., the power allocation among the N battery packs is determined. To ensure a more balanced distribution of remaining capacity among the battery packs and achieve better balancing, the remaining capacity of the (N+1)th battery pack is also taken into account when determining the power allocation among the N battery packs, and is determined based on the remaining capacity of the first N+1 battery packs.

[0071] Specifically, please refer to Figure 3 Step S25 includes:

[0072] S251. Obtain the first difference between the remaining capacity of the first N battery packs and the remaining capacity of the (N+1)th battery pack;

[0073] This step yields N first differences. For example, if N is 2, and the remaining capacities of the first N+1 battery packs are A1 = 1600Wh, A2 = 1200Wh, and A3 = 800Wh, then there are two first differences: Δ1 = A1 - A3 = 800Wh and Δ2 = A2 - A3 = 400Wh.

[0074] S252. Based on the difference ratio of the first difference and the output power of the load, determine the allocated power of the first N battery packs in the sorting table.

[0075] The ratio of the first difference is used as the power distribution ratio of the battery pack. For example, as mentioned above, there are two first differences, Δ1 = 800Wh and Δ2 = 400Wh. The ratio of the first difference is Δ1:Δ2 = 800Wh:400Wh = 2:1. Therefore, the power distribution ratio of the first two battery packs is 2:1. If A1 = 1600Wh, A2 = 1200Wh, and the load output power P is 2000W, then the power distribution of the first battery pack is P1 = 2 / 3 * 2000W = 1333W, P2 = 1 / 3 * 2000W = 667W, that is, P1:P2 = 2:1.

[0076] That is, firstly, the difference in remaining capacity between the first N battery packs and the (N+1)th battery pack is obtained. Then, based on the ratio of the differences between each difference and the output power of the load, the allocated power of the first N battery packs is determined. By linking the allocated power of the first N battery packs to the remaining capacity of the (N+1)th battery pack, as the first N battery packs discharge, their remaining capacity gradually approaches that of the (N+1)th battery pack. Compared to methods that directly obtain the allocated power based on the ratio of remaining capacity, this allocation method results in a more balanced remaining capacity among the battery packs, achieving a better overall balance.

[0077] S26. Power the load according to the allocated power of the first N battery packs and the maximum output power;

[0078] The power allocated to the first N battery packs is a theoretically calculated value. It may be greater than the maximum output power of the battery pack, or it may be less than or equal to the maximum output power of the battery pack. Therefore, the final power for supplying power to the load needs to be determined based on the power allocated to the battery packs and their corresponding maximum output power.

[0079] In some embodiments, if the allocated power of a battery pack exceeds its corresponding maximum output power, the battery pack will output power at its maximum output power to supply power to the load, and the excess power will be allocated to other battery packs that have not exceeded their maximum output power, according to the proportion of the first difference in the aforementioned embodiments. Specifically, please refer to... Figure 4 Step S26 includes:

[0080] S261. If the allocated power is greater than the corresponding maximum output power, then the allocated power of the corresponding battery pack is determined as the corresponding maximum output power, and a second difference between the allocated power and the maximum output power is obtained.

[0081] S262. According to the difference ratio, the second difference is allocated to the first N battery packs that have not exceeded the maximum output power to obtain the new allocated power;

[0082] S263. Control the battery pack to supply power to the load according to the new power allocation.

[0083] If the calculated allocated power is greater than its corresponding maximum output power, the battery pack will trigger a protection mechanism to further regulate and supply power to the load according to the maximum output power of the battery pack. Furthermore, the portion of the calculated allocated power that exceeds the maximum output power of the battery pack will be allocated to other battery packs that have not exceeded their maximum output power according to the difference ratio, thus obtaining a new allocated power.

[0084] For example: Assume each battery pack has a maximum output power of 1200W, and the load output power P is 2000W. Then N=2, and the remaining SOCs of the first N+1 battery packs are A1=1600Wh, A2=1200Wh, and A3=800Wh respectively. The calculated power allocation for battery pack A1 is P1=(A1-A3) / (A1+A2-2A3)*P=800 / 1200*2000W=1333W. The calculated power allocation for battery pack A2 is P2=667W. However, when A1 outputs 1333W, it exceeds its maximum output power of 1200W. Therefore, controlling the output of battery pack A1 to 1200W, the difference between its allocated power and its maximum output power is 133W. This 133W is then allocated to battery pack A2, resulting in an output of 667W+133W=800W for battery pack A2.

[0085] For example, if the load output power is 3000W and the maximum output power of each battery pack is 1200W, then N=3 battery packs are needed for parallel output. The remaining SOC of the first N+1 battery packs are A1=1600Wh, A2=1200Wh, A3=800Wh, and A4=400W, respectively. The calculated power allocations for A1, A2, and A3 are 1500W, 1000W, and 500W respectively. Since the 1500W power allocation for battery pack A1 exceeds its maximum output power, battery pack A1 is controlled to supply power to the load at its maximum output of 1200W. The excess 300W is allocated to battery packs A2 and A3 in the ratio (A2-A4):(A3-A4) = (1200-400):(800-400). Therefore, the new power allocation for battery pack A2 is 1200W, and for battery pack A3 it is 600W. Battery packs A2 and A3 are then controlled to supply power to the load according to this new power allocation. Theoretically, the remaining SOC of battery packs A2 and A3 will simultaneously reach the same level as the remaining SOC of battery pack A4.

[0086] When the distributed power of a battery pack exceeds its maximum output power, the battery pack supplies power to the load at its maximum output power while simultaneously distributing the excess power to other battery packs that have not exceeded their maximum output power, proportionally based on the difference in remaining capacity. Through this method, as the first N battery packs discharge, at least one of the first N battery packs will have a remaining capacity equal to that of the (N+1)th battery pack. Only when at least one of the first N battery packs has a remaining capacity equal to that of the (N+1)th battery pack will the subsequent operations of this discharge method be performed.

[0087] Therefore, the above method of obtaining and distributing power not only meets the power supply requirements of the load, but also makes the remaining power of each battery pack as balanced as possible, achieving a better balanced discharge effect, thereby extending the discharge time of the battery pack.

[0088] In some embodiments, if the allocated power is less than or equal to the corresponding maximum output power, the battery pack is controlled to supply power to the load according to the allocated power. When the allocated power is obtained according to this method and the load is supplied according to the allocated power, as the N battery packs discharge, the remaining capacity of the N battery packs will simultaneously decrease to the remaining capacity of the (N+1)th battery pack, that is, the remaining capacity of the N battery packs will simultaneously be equal to the remaining capacity of the (N+1)th battery pack. When the remaining capacity of the N battery packs simultaneously decreases to the remaining capacity of the (N+1)th battery pack, the subsequent operations of the discharge method are then performed.

[0089] Therefore, this method of obtaining and distributing power allows the remaining capacity of the battery pack to gradually reach equilibrium during the discharge process, achieving a better balanced discharge effect.

[0090] S27. When the remaining capacity of at least one of the N battery packs is equal to the remaining capacity of the (N+1)th battery pack, the (N+1)th battery pack is incorporated, so that the first N+1 battery packs supply power to the load according to the allocated power of the battery packs and the maximum output power, wherein N+1≤M; and so on, until M battery packs are incorporated.

[0091] If the distributed power of the battery pack is greater than the maximum output power, then as the first N battery packs discharge, at least one of the first N battery packs will have a remaining capacity equal to the remaining capacity of the (N+1)th battery pack. If the distributed power of the battery pack is less than or equal to the maximum output power, then as the first N battery packs discharge, the remaining capacity of the first N battery packs will simultaneously be equal to the remaining capacity of the (N+1)th battery pack.

[0092] If the remaining capacity of at least one of the N battery packs is equal to the remaining capacity of the (N+1)th battery pack, then the (N+1)th battery pack is added. The power allocation method described above is then used to obtain the allocated power of the first N+1 battery packs. Power is then supplied to the load based on the allocated power and the maximum output power to ensure normal operation. If the remaining capacity of at least one of the N+1 battery packs is equal to the remaining capacity of the (N+2)th battery pack, then the (N+2)th battery pack is added, and the power allocation of each battery pack is redistributed. This process continues until all M battery packs are added.

[0093] In summary, this discharge method first supplies power to the load using the first N battery packs with higher charge, and correlates the power distribution of the first N battery packs with the remaining capacity of the first N+1 battery packs. This ensures that as the first N battery packs discharge, the remaining capacity of at least one of them becomes equal to the remaining capacity of the (N+1)th battery pack. Then, the (N+1)th battery pack is added, and this process continues until all M battery packs are added. Therefore, compared to discharge methods that directly use all M battery packs, this method ensures that the remaining capacity of each battery pack is as equal as possible during discharge, balancing the remaining capacity of each battery pack and achieving a better balanced discharge effect. Furthermore, when the load output power is increased, because this discharge method makes the remaining capacity of each battery pack more balanced and adds M battery packs one by one, it can extend the battery pack discharge time and improve the battery pack discharge efficiency. Additionally, since each battery pack can be driven independently, when the user does not need to use parallel charging technology, it can ensure that the charge of each battery pack is balanced, making it convenient for the user.

[0094] In some embodiments, the discharge method of the parallel energy storage device further includes: real-time detection of whether the output power of the load changes; when the output power of the load connected to the parallel energy storage device changes, returning to the step of determining the number N of battery packs supplying power to the load based on the output power of the load, the maximum output power, and the sorting table, and then re-determining the number of battery packs supplying power to the load and the power allocation of each battery pack to achieve normal power supply to the load. Therefore, this discharge method can adjust the number of battery packs supplying power to the load and the power allocation of each battery pack in real time according to changes in the output power of the load, enabling the load to operate normally, meeting the load's power demand in a timely manner, and facilitating user operation.

[0095] Figure 5This is a schematic diagram of the structure of a discharge device for a parallel energy storage device provided in an embodiment of the present invention. The discharge device 200 of the parallel energy storage device includes a first acquisition module 201, used to acquire the remaining capacity and maximum output power of each battery pack; a sorting module 202, used to sort the battery packs from high to low according to the remaining capacity of each battery pack to obtain a sorting table; a second acquisition module 203, used to acquire the output power of the load connected to the parallel energy storage device; a first determination module 204, used to determine the number N of battery packs supplying power to the load according to the output power of the load, the maximum output power and the sorting table; and a second determination module 205, used to determine the number N of battery packs supplying power to the load according to the first N+1 battery packs in the sorting table. The remaining capacity and the output power of the load are used to determine the allocated power of the first N battery packs in the sorting table, where N+1≤M, and the allocated power is the required output power of the first N battery packs; the power supply module 206 is used to supply power to the load according to the allocated power of the first N battery packs and the maximum output power; the integration module 207 is used to integrate the N+1 battery pack when the remaining capacity of at least one of the current N battery packs is equal to the remaining capacity of the N+1 battery pack, so that the first N+1 battery packs supply power to the load according to the allocated power of the battery packs and the maximum output power, where N+1≤M; and so on, until M battery packs are integrated.

[0096] Therefore, in this embodiment, the discharge device of the parallel energy storage device ensures that the remaining capacity of each battery pack is as equal as possible during the discharge process, balancing the remaining capacity of each battery pack and achieving a better balanced discharge effect. Furthermore, when the output power of the load increases, because this discharge method makes the remaining capacity of each battery pack more balanced, and by sequentially connecting the M battery packs, the discharge time of the battery packs can be extended, improving the discharge efficiency of the battery packs. In addition, since each battery pack can be driven independently, when the user does not need to use parallel charging technology, the power balance of each battery pack can be guaranteed, making it convenient for the user.

[0097] It should be noted that since the discharge device of the parallel energy storage device and the discharge method of the parallel energy storage device in the above embodiments are based on the same inventive concept, the corresponding contents in the above method embodiments are also applicable to the device embodiments, and will not be described in detail here.

[0098] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of a controller provided in an embodiment of the present invention. Figure 6 As shown, the controller 23 includes one or more processors 231 and a memory 232. Wherein, Figure 6 Take the 231 processor as an example.

[0099] The processor 231 and the memory 232 can be connected via a bus or other means. Figure 6 Taking the example of a connection between China and Israel via a bus.

[0100] The memory 232, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the discharge method of the parallel energy storage device in the embodiments of the present invention. The processor 231 executes various functional applications and data processing of the discharge device of the parallel energy storage device by running the non-volatile software programs, instructions, and modules stored in the memory 232, thereby realizing the functions of the discharge method of the parallel energy storage device provided in the above method embodiments and the various modules or units in the above device embodiments.

[0101] Memory 232 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, memory 232 may optionally include memory remotely located relative to processor 231, and such remote memory may be connected to processor 231 via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0102] The program instructions / modules are stored in the memory 232. When executed by one or more processors 231, they execute the discharge method of the parallel energy storage device in any of the above method embodiments.

[0103] This invention also provides a non-transitory computer-readable storage medium storing computer-executable instructions that are executed by one or more processors, for example... Figure 6 One of the processors 231 can enable the one or more processors to execute the discharge method of the parallel energy storage device in any of the above method embodiments.

[0104] This invention also provides a non-volatile computer storage medium storing computer-executable instructions that are executed by one or more processors, for example... Figure 6 One of the processors 231 can enable the one or more processors to execute the discharge method of the parallel energy storage device in any of the above method embodiments.

[0105] This invention also provides a computer program product, which includes a computer program stored on a non-volatile computer-readable storage medium. The computer program includes program instructions that, when executed by a controller, cause the controller to perform the discharge method of any of the parallel energy storage devices described in the present invention.

[0106] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, or of course, using hardware. Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program in a computer program product instructing related hardware. The computer program can be stored in a non-transitory computer-readable storage medium. The computer program includes program instructions, which, when executed by the UAV, cause the UAV to execute the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0107] The discharge method of this parallel energy storage device ensures that the remaining capacity of each battery pack is as equal as possible during discharge, balancing the remaining capacity of each battery pack and achieving a better balanced discharge effect. Furthermore, when the output power of the load increases, because this discharge method makes the remaining capacity of each battery pack more balanced, and by sequentially connecting M battery packs, the discharge time of the battery packs can be extended, improving the discharge efficiency. In addition, since each battery pack can be driven independently, when the user does not need to use parallel technology, it can ensure the balanced charge of each battery pack, making it convenient for the user.

[0108] To power high-power devices, multiple battery packs are typically connected to the main unit, with each pack outputting a certain power to drive the high-power load. However, in the parallel storage technology of multiple battery packs, there are various combined discharge methods. Existing energy storage devices usually select only one discharge method, meaning users can only discharge multiple battery packs using this method. For example, users might want a longer discharge time in one period and a more balanced State of Charge (SOC) across all battery packs in another. This approach fails to meet diverse user needs and results in a poor user experience.

[0109] Based on this, the present invention provides an energy storage system that pre-stores multiple discharge modes and multiple control commands, wherein at least one discharge mode adopts the discharge method of the parallel energy storage device as described in any of the above embodiments, and each control command corresponds to a discharge mode. The energy storage system is used to receive control commands, obtain the corresponding discharge mode according to the control commands, and use the corresponding discharge mode to supply power to the load.

[0110] Control commands can take many forms, such as control signals sent by the user through an app, press signals obtained by the user pressing the corresponding function button on the energy storage system, voice signals issued by the user, or control signals sent by the user through the touch panel on the energy storage system.

[0111] The discharge mode can be multiple modes, including existing discharge modes and discharge modes set by the user in real time. For example, the user can edit and set a discharge mode in real time and store it in the energy storage system. The energy storage system will then establish a correspondence between the discharge mode and the corresponding control command so that the user can select it.

[0112] Therefore, for different loads, the corresponding discharge mode in the energy storage system can be selected to discharge the load, thereby maximizing the discharge efficiency. The system is flexible in its use, convenient for users, and improves the user experience.

[0113] Please see Figure 7 , Figure 7 This is a schematic diagram of the working process of an energy storage system provided in an embodiment of the present invention, as shown below. Figure 7 As shown, the working principle of this energy storage system can be described as follows:

[0114] S71. Store multiple discharge modes into the energy storage system;

[0115] Specifically, in the technology of parallel discharge of multiple battery packs, there are various discharge modes, such as:

[0116] The first discharge mode: Based on the remaining SOC of each battery pack and the load output power, determine the output power of each battery pack to ensure the normal operation of the load.

[0117] The second discharge mode: the discharge method of the parallel energy storage device as described in any of the above embodiments.

[0118] The third discharge mode: multiple battery packs discharge sequentially, that is, after one battery pack is depleted, another battery pack is used to discharge.

[0119] The fourth discharge mode is the battery pack mutual charging mode, which balances the power of multiple battery packs before discharging them to the outside.

[0120] It should be noted that the discharge modes are not limited to the four mentioned above, and the discharge modes stored in the energy storage system can be any two or more discharge modes.

[0121] S72. Establish a one-to-one correspondence between multiple control commands and multiple discharge modes;

[0122] Specifically, for example, there are four discharge modes: the first discharge mode, the second discharge mode, the third discharge mode, and the fourth discharge mode. There are also four control commands: the first control command, the second control command, the third control command, and the fourth control command. The first control command corresponds to the first discharge mode, the second control command corresponds to the second discharge mode, and so on.

[0123] S73, Receive control commands;

[0124] Specifically, if the energy storage system has function switches, users can issue control commands by adjusting the switch settings. Alternatively, users can issue control commands via an app. Another example is a touch panel on the energy storage system, through which users can select the discharge mode.

[0125] The first, second, third, and fourth control commands can be commands acquired in different ways. For example, the first control command is a control command issued by the user by adjusting the switch position, the second control command is a voice command issued by the user, and so on.

[0126] S74. Obtain the discharge mode corresponding to the control command;

[0127] Specifically, the control command type is analyzed, and the required discharge mode is determined based on the correspondence between the control command and various discharge modes.

[0128] S75, control the multiple battery packs of the energy storage system to discharge according to their corresponding discharge modes.

[0129] The battery pack discharges according to the corresponding discharge mode to meet user needs. At the same time, during the discharge process, the energy storage system still receives control commands. If the control commands change, it will obtain the discharge mode corresponding to the changed control commands again and control the battery pack to discharge according to the new discharge mode.

[0130] The discharge control method of the above-mentioned energy storage system pre-stores multiple discharge modes in the energy storage system and executes the corresponding discharge mode according to the control command issued by the user, so as to meet the diverse needs of the user.

[0131] Furthermore, in one embodiment, the discharge control method of the energy storage system further includes setting one of a variety of discharge modes as the default discharge mode, and executing the discharge in the default discharge mode when no control command is received from the user. Preferably, the discharge mode of the parallel energy storage device described in any of the above embodiments is set as the default mode.

[0132] In summary, this energy storage system pre-stores multiple discharge modes and executes the corresponding mode based on the control commands received from the user. Different discharge modes can be selected for different loads, maximizing discharge efficiency, meeting diverse user needs, offering flexible usage, and enhancing the user experience.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method of discharging parallel energy storage devices, characterized by, The parallel energy storage device includes M parallel battery packs, where M is greater than 2, and the method includes: obtaining the remaining capacity and the maximum output power of each battery pack; sorting the battery packs according to the remaining capacity of each battery pack from high to low to obtain a sorting table; obtaining the output power of a load connected to the parallel energy storage device; determining the number N of battery packs for supplying power to the load according to the output power of the load, the maximum output power, and the sorting table; determining the distribution power of the first N battery packs in the sorting table according to the remaining capacity of the first N+1 battery packs in the sorting table and the output power of the load; the determination of the distribution power of the first N battery packs in the sorting table according to the remaining capacity of the first N+1 battery packs and the output power of the load includes: obtaining the first difference between the remaining capacity of the first N battery packs and the remaining capacity of the N+1 battery pack; determining the distribution power of the first N battery packs in the sorting table according to the difference ratio of the first difference and the output power of the load, with the difference ratio of the first difference as the ratio of the distribution power of the battery packs; where N+1≤M, and the distribution power is the output power required by the first N battery packs; supplying power to the load according to the distribution power of the first N battery packs and the maximum output power; the power supply to the load according to the distribution power of the first N battery packs and the maximum output power includes: if the distribution power is less than or equal to the corresponding maximum output power, controlling the battery packs to supply power to the load according to the distribution power; if the distribution power is greater than the corresponding maximum output power, determining the distribution power of the corresponding battery pack as the corresponding maximum output power, and obtaining a second difference between the distribution power and the maximum output power; distributing the second difference to the battery packs in the first N battery packs that do not exceed the maximum output power according to the difference ratio to obtain new distribution power; controlling the battery packs to supply power to the load according to the new distribution power; when the remaining capacity of at least one battery pack in the first N battery packs is equal to the remaining capacity of the N+1 battery pack, incorporating the N+1 battery pack to make the first N+1 battery packs supply power to the load according to the distribution power of the battery packs and the maximum output power, where N+1≤M; and the same applies to the incorporation of M battery packs.

2. The method of claim 1, wherein, The determination of the number N of battery packs for supplying power to the load according to the output power of the load, the maximum output power, and the sorting table includes: if each maximum output power is the same, determining the number N of battery packs for supplying power to the load by the following formula: N=int (P / Pmax); where int(...) represents rounding up, P is the output power of the load, and Pmax is the maximum output power.

3. The method of claim 2, wherein, The number N of the battery packs for supplying power to the load is determined according to the output power of the load, the maximum output power and the ranking table, including: When the maximum output power is different, if the difference between the first sum and the output power of the load is less than or equal to a preset threshold, the number of the battery packs for supplying power to the load is determined as N, wherein the first sum is the sum of the maximum output power of the first N battery packs in the ranking table.

4. The method of claim 1, wherein, The method further includes: when the output power of the load connected to the parallel energy storage device changes, returning to the step of determining the number N of the battery packs for supplying power to the load according to the output power of the load, the maximum output power and the ranking table.

5. A controller characterized by comprising: The controller includes at least one processor; and a memory connected in communication with the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the discharging method of the parallel energy storage device according to any one of claims 1-4.

6. An energy storage inverter, characterized by, The energy storage inverter includes a parallel energy storage module and an inverter module; The parallel energy storage module includes M parallel battery packs, wherein M is greater than 2; The inverter module includes M parallel DC / DC conversion modules, an inverter module and the controller according to claim 5, wherein the battery packs are connected to the input ends of the DC / DC conversion modules one by one, the output ends of the DC / DC conversion modules are first connected in parallel and then connected to the input ends of the inverter module, and the battery packs, the DC / DC conversion modules and the inverter module are all connected to the controller.

7. An energy storage system characterized by, The energy storage system pre-stores a plurality of discharging modes and a plurality of control instructions, wherein at least one of the discharging modes adopts the discharging method of the parallel energy storage device according to any one of claims 1-4, and each control instruction corresponds to a discharging mode; the energy storage system is configured to receive the control instructions, obtain the corresponding discharging mode according to the control instructions, and supply power to the load by using the corresponding discharging mode.

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