Power distribution method and device of energy storage power station and energy storage power station

Abstract

The application discloses a power distribution method and device of an energy storage power station and the energy storage power station, and belongs to the technical field of electric power energy storage. The capacity weight coefficient overflow amount of each energy storage unit and the capacity weight coefficient overflow total amount of all energy storage units are determined according to the power weight coefficient and the capacity weight coefficient of each energy storage unit. If the capacity weight coefficient overflow total amount is 0, the total issued power of the energy storage power station is distributed to each energy storage unit according to the capacity weight coefficient; otherwise, the overflow amount of the overflow unit is evenly distributed to the non-overflow unit. The new capacity weight coefficient of each energy storage unit is determined through the capacity weight coefficient correction amount of each energy storage unit, and the capacity weight coefficient overflow amount of each energy storage unit and the capacity weight coefficient overflow total amount of the all energy storage units are determined again until the capacity weight coefficient overflow total amount is 0. Finally, the balance between the residual capacity of the energy storage unit and the power distribution is achieved, and the SOC of each energy storage unit is balanced.

Description

Technical Field

[0001] This invention relates to the technical field of power energy storage, and in particular to a power distribution method for an energy storage power station, a power distribution device for an energy storage power station, and an energy storage power station. Background Technology

[0002] With the increasing maturity of electrochemical energy storage technology, its application in power grids is becoming more and more widespread. Due to the rapid growth in the installed capacity of new energy power plants such as photovoltaic and wind power, as well as charging stations, the intermittent and fluctuating characteristics of the power system are becoming increasingly apparent. The power grid's regulation power gap is constantly widening, and the demand for large-capacity energy storage technology (hundreds of megawatts and above) is becoming increasingly strong. Electrochemical energy storage systems generally achieve energy storage and release through a combination of cells-packs-clusters-cluster groups-energy storage units. Cells, packs, clusters, and cluster groups need to be connected in series and parallel to meet the system's voltage and capacity requirements. In particular, clusters are generally connected in parallel to form cluster groups, which presents problems such as large short-circuit current, large fault range, easy formation of circulating current, and poor battery balancing capability. Therefore, the current development trend of energy storage systems is to prioritize the use of small battery clusters connected in series with small energy storage units to form modular small systems (energy storage units), and then connect multiple energy storage units in parallel to construct large-capacity energy storage power stations.

[0003] During the operation of an energy storage power station, the power command for the entire power station needs to be distributed among the individual energy storage units. However, in a parallel structure of multiple energy storage units, inconsistencies in SOC (State of Charge, i.e., the ratio of remaining battery capacity to its rated capacity) are very likely to occur among the individual units. If the total power demand is simply distributed to the individual energy storage units using an averaging method, it usually leads to unreasonable deviations between the total power demand and the actual response of the energy storage power station, as well as problems such as individual energy storage units reaching their charging upper limit or discharging lower limit earlier than others. This not only reduces the accuracy of the energy storage power station's response to power commands but also wastes the capacity of the energy storage system. If the imbalance between energy storage units is not addressed, it will also accelerate the decline in the overall operational life of the energy storage power station. Furthermore, existing SOC balancing methods for energy storage power stations typically require that the key specifications of each energy storage unit within the power station be consistent, such as rechargeable power, dischargeable power, and rated battery capacity. Otherwise, accurate power allocation results cannot be obtained. This undoubtedly greatly limits the applicability of such SOC balancing algorithms and cannot meet the requirements of SOC balancing control for energy storage power station systems with increasingly larger scales and more energy storage units. Summary of the Invention

[0004] The main objective of this invention is to provide a power distribution method, a power distribution device, and an energy storage power station, aiming to solve the technical problem of accurately and reasonably distributing power to the energy storage units of an energy storage power station in the prior art.

[0005] To achieve the above objectives, the present invention provides a power allocation method for an energy storage power station, the energy storage power station comprising multiple energy storage units, the power allocation method comprising the following steps:

[0006] Determine the total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit;

[0007] The capacity weight coefficient overflow of each energy storage unit is calculated based on the power weight coefficient and the capacity weight coefficient of each energy storage unit.

[0008] If any of the capacity weight coefficient overflows, the capacity weight coefficient correction amount, new capacity weight coefficient, and new capacity weight coefficient overflow of each energy storage unit are calculated based on the capacity weight coefficient overflow of each energy storage unit, the remaining available capacity of each energy storage unit, the capacity weight coefficient, and the power weight coefficient, until any of the new capacity weight coefficient overflows is 0.

[0009] The total output power of the energy storage power station is allocated to each energy storage unit according to the capacity weight coefficient when the overflow amount is 0.

[0010] Optionally, the step of determining the total power output of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit includes:

[0011] Obtain the total power demand of the energy storage power station, the maximum rechargeable power, the maximum dischargeable power, and the remaining available capacity of each energy storage unit;

[0012] The total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit are calculated based on the total power demand of the energy storage power station and the maximum rechargeable power, maximum dischargeable power, and remaining available capacity of each energy storage unit.

[0013] The charging power is represented by a negative value, and the discharging power is represented by a positive value.

[0014] Optionally, the step of calculating the total power output of the energy storage power station includes:

[0015] When the total demand power of the energy storage power station is equal to the charging power, the maximum rechargeable power of each energy storage unit is summed to obtain the total maximum rechargeable power value, and the larger value of the total demand power and the total maximum rechargeable power value is determined as the total output power of the energy storage power station.

[0016] When the total demand power of the energy storage power station is equal to the discharge power, the maximum dischargeable power of each energy storage unit is summed to obtain the total maximum dischargeable power value, and the smaller value between the total demand power and the total maximum dischargeable power value is determined as the total output power of the energy storage power station.

[0017] Optionally, the step of obtaining the remaining available capacity of each of the energy storage units includes:

[0018] When the total demand power of the energy storage power station is the charging power, determine the upper limit of the state of charge of the battery in each energy storage unit and the first charge difference of the current state of charge, and determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the first charge difference.

[0019] When the total demand power of the energy storage power station is the discharge power, determine the current state of charge of the battery in each energy storage unit and the second charge difference value of the state of charge limit. Determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the second charge difference value.

[0020] Optionally, the step of calculating the power weighting coefficient of each of the energy storage units includes:

[0021] When the total power demand of the energy storage power station is the charging power, the ratio of the maximum rechargeable power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0022] When the total power demand of an energy storage power station is equal to the discharge power, the ratio of the maximum discharge power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0023] Optionally, the step of calculating the capacity weighting coefficient of each of the energy storage units includes:

[0024] The total remaining available capacity is obtained by summing up the remaining available capacity of each energy storage unit;

[0025] The capacity weighting coefficient of each energy storage unit is determined based on the remaining available capacity of each energy storage unit and the total remaining available capacity.

[0026] Optionally, the step of calculating the capacity weighting coefficient overflow of each energy storage unit includes:

[0027] Determine the weighting coefficient difference between the capacity weighting coefficient and the power weighting coefficient for each energy storage unit;

[0028] When the difference in the weighting coefficients is greater than 0, the overflow amount of the capacity weighting coefficients is determined to be the difference in the weighting coefficients.

[0029] When the difference in the weighting coefficients is less than or equal to 0, the overflow amount of the capacity weighting coefficient is determined to be 0.

[0030] Optionally, the step of calculating the capacity weighting coefficient correction amount for each energy storage unit includes:

[0031] When the capacity weight coefficient overflow is greater than 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be an overflow unit, and the capacity weight coefficient correction amount of the overflow unit is determined to be 0.

[0032] When the capacity weight coefficient overflow is equal to 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be a non-overflow unit; the capacity weight coefficient overflow of each energy storage unit is summarized to obtain the total capacity weight coefficient overflow; the remaining available capacity of each non-overflow unit is summarized to obtain the total remaining available capacity of the non-overflow units; and the capacity weight coefficient correction amount of the non-overflow unit is calculated based on the remaining available capacity of each non-overflow unit, the total remaining available capacity, and the total capacity weight coefficient overflow.

[0033] Optionally, the step of calculating the capacity weighting coefficient correction amount of the non-overflow unit includes:

[0034] The ratio of the remaining available capacity of each non-overflow unit to the total remaining available capacity is multiplied by the total overflow amount of the capacity weight coefficient, and the result is used as the correction amount of the capacity weight coefficient of each non-overflow unit.

[0035] Optionally, the step of calculating the new capacity weighting coefficient for each energy storage unit includes:

[0036] The difference between the capacity weight coefficient and the overflow amount of the capacity weight coefficient for each energy storage unit, plus the correction amount of the capacity weight coefficient, is used as the new capacity weight coefficient for each energy storage unit.

[0037] In addition, to achieve the above objectives, the present invention also provides a power distribution device for an energy storage power station, the power distribution device for the energy storage power station comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the power distribution method for the energy storage power station as described above.

[0038] In addition, to achieve the above objectives, the present invention also provides an energy storage power station, which includes the power distribution device as described above and a plurality of energy storage units connected to the power distribution device, wherein the power distribution device distributes the total power output of the energy storage power station to each of the energy storage units.

[0039] This invention proposes a power allocation method, a power allocation device, and an energy storage power station. The method involves determining the total output power of the energy storage power station, the power weight coefficient of each energy storage unit, and the capacity weight coefficient of each energy storage unit. Based on the power weight coefficient and capacity weight coefficient of each energy storage unit, the overflow amount of the capacity weight coefficient of each energy storage unit is calculated. If any overflow amount of the capacity weight coefficient is not zero, based on the overflow amount of the capacity weight coefficient of each energy storage unit, the remaining available capacity of each energy storage unit, the capacity weight coefficient, and the power weight coefficient, the capacity weight coefficient correction amount, a new capacity weight coefficient, and a new capacity weight coefficient overflow amount of each energy storage unit are calculated until any new capacity weight coefficient overflow amount is zero. The total output power of the energy storage power station is allocated to each energy storage unit according to the capacity weight coefficient when the capacity weight coefficient overflow amount is zero.

[0040] First, the capacity weight coefficient overflow of each energy storage unit and the total capacity weight coefficient overflow of all energy storage units are determined based on the power weight coefficient and capacity weight coefficient of each energy storage unit. Then, if the total capacity weight coefficient overflow is 0, the total output power P of the energy storage power station is directly allocated to each energy storage unit according to the capacity weight coefficient. If the total capacity weight coefficient overflow is not 0, it means that if the total output power P of the energy storage power station is directly allocated to each energy storage unit according to the current capacity weight coefficient, some energy storage units will not be able to fully respond to the power command, which will eventually cause the actual response power of the entire energy storage power station to deviate from the total output power. Therefore, it is necessary to evenly distribute the overflow of the overflow units to the non-overflow units. The new capacity weight coefficient of each energy storage unit is determined by the correction amount of the capacity weight coefficient of each energy storage unit, and the capacity weight coefficient overflow of each energy storage unit and the total capacity weight coefficient overflow of all energy storage units are re-determined until the total capacity weight coefficient overflow is 0, so as to achieve a balance between the remaining capacity and power allocation of the energy storage units and make the SOC of each energy storage unit reach equilibrium.

[0041] By comprehensively considering the actual usable capacity of the energy storage units and the SOC deviation between each energy storage unit, the total output power is rationally allocated to make the SOC of each energy storage unit more consistent. This solves the problem of accurately and rationally allocating power to the energy storage units of the energy storage power station, avoids the deviation between the total output power and the actual response power of the overall energy storage system, thereby reducing the waste of energy storage power station capacity and extending the overall operating life of the energy storage power station. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the operating device of the hardware operating environment involved in the embodiments of the present invention;

[0043] Figure 2 This is a schematic flowchart of an embodiment of a power allocation method for an energy storage power station according to the present invention;

[0044] Figure 3 This is a schematic diagram of a multi-unit energy storage power station system involved in the embodiments of the present invention.

[0045] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0046] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0047] Reference Figure 1 , Figure 1 This is a schematic diagram of the operating device of the hardware operating environment involved in the embodiments of the present invention.

[0048] like Figure 1 As shown, the operating device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen and an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0049] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the operating equipment and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0050] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a data storage module, a network communication module, a user interface module, and computer programs.

[0051] exist Figure 1 In the illustrated operating device, the network interface 1004 is mainly used for data communication with other devices; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and memory 1005 in the operating device of the present invention can be installed in the operating device, and the operating device calls the computer program stored in the memory 1005 through the processor 1001 and performs the following operations:

[0052] Determine the total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit;

[0053] The capacity weight coefficient overflow of each energy storage unit is calculated based on the power weight coefficient and the capacity weight coefficient of each energy storage unit.

[0054] If any of the capacity weight coefficient overflows, the capacity weight coefficient correction amount, new capacity weight coefficient, and new capacity weight coefficient overflow of each energy storage unit are calculated based on the capacity weight coefficient overflow of each energy storage unit, the remaining available capacity of each energy storage unit, the capacity weight coefficient, and the power weight coefficient, until any of the new capacity weight coefficient overflows is 0.

[0055] The total output power of the energy storage power station is allocated to each energy storage unit according to the capacity weight coefficient when the overflow amount is 0.

[0056] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0057] The steps for determining the total power output of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit include:

[0058] Obtain the total power demand of the energy storage power station, the maximum rechargeable power, the maximum dischargeable power, and the remaining available capacity of each energy storage unit;

[0059] The total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit are calculated based on the total power demand of the energy storage power station and the maximum rechargeable power, maximum dischargeable power, and remaining available capacity of each energy storage unit.

[0060] The charging power is represented by a negative value, and the discharging power is represented by a positive value.

[0061] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0062] The step of calculating the total power output of the energy storage power station includes:

[0063] When the total demand power of the energy storage power station is equal to the charging power, the maximum rechargeable power of each energy storage unit is summed to obtain the total maximum rechargeable power value, and the larger value of the total demand power and the total maximum rechargeable power value is determined as the total output power of the energy storage power station.

[0064] When the total demand power of the energy storage power station is equal to the discharge power, the maximum dischargeable power of each energy storage unit is summed to obtain the total maximum dischargeable power value, and the smaller value between the total demand power and the total maximum dischargeable power value is determined as the total output power of the energy storage power station.

[0065] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0066] The step of obtaining the remaining available capacity of each of the energy storage units includes:

[0067] When the total demand power of the energy storage power station is the charging power, determine the upper limit of the state of charge of the battery in each energy storage unit and the first charge difference of the current state of charge, and determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the first charge difference.

[0068] When the total demand power of the energy storage power station is the discharge power, determine the current state of charge of the battery in each energy storage unit and the second charge difference value of the state of charge limit. Determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the second charge difference value.

[0069] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0070] The step of calculating the power weighting coefficient of each of the energy storage units includes:

[0071] When the total power demand of the energy storage power station is the charging power, the ratio of the maximum rechargeable power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0072] When the total power demand of an energy storage power station is equal to the discharge power, the ratio of the maximum discharge power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0073] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0074] The step of calculating the capacity weighting coefficient of each of the energy storage units includes:

[0075] The total remaining available capacity is obtained by summing up the remaining available capacity of each energy storage unit;

[0076] The capacity weighting coefficient of each energy storage unit is determined based on the remaining available capacity of each energy storage unit and the total remaining available capacity.

[0077] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0078] The step of calculating the capacity weighting coefficient overflow of each energy storage unit includes:

[0079] Determine the weighting coefficient difference between the capacity weighting coefficient and the power weighting coefficient for each energy storage unit;

[0080] When the difference in the weighting coefficients is greater than 0, the overflow amount of the capacity weighting coefficients is determined to be the difference in the weighting coefficients.

[0081] When the difference in the weighting coefficients is less than or equal to 0, the overflow amount of the capacity weighting coefficient is determined to be 0.

[0082] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0083] The step of calculating the capacity weighting coefficient correction amount for each energy storage unit includes:

[0084] When the capacity weight coefficient overflow is greater than 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be an overflow unit, and the capacity weight coefficient correction amount of the overflow unit is determined to be 0.

[0085] When the capacity weight coefficient overflow is equal to 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be a non-overflow unit; the capacity weight coefficient overflow of each energy storage unit is summarized to obtain the total capacity weight coefficient overflow; the remaining available capacity of each non-overflow unit is summarized to obtain the total remaining available capacity of the non-overflow units; and the capacity weight coefficient correction amount of the non-overflow unit is calculated based on the remaining available capacity of each non-overflow unit, the total remaining available capacity, and the total capacity weight coefficient overflow.

[0086] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0087] The step of calculating the capacity weighting coefficient correction amount of the non-overflow unit includes:

[0088] The ratio of the remaining available capacity of each non-overflow unit to the total remaining available capacity is multiplied by the total overflow amount of the capacity weight coefficient, and the result is used as the correction amount of the capacity weight coefficient of each non-overflow unit.

[0089] Furthermore, the processor 1001 can call a computer program stored in the memory 1005 and also perform the following operations:

[0090] The step of calculating the new capacity weighting coefficient for each energy storage unit includes:

[0091] The difference between the capacity weight coefficient and the overflow amount of the capacity weight coefficient for each energy storage unit, plus the correction amount of the capacity weight coefficient, is used as the new capacity weight coefficient for each energy storage unit.

[0092] Reference Figure 2 , Figure 2 This is a flowchart illustrating an embodiment of a power allocation method for an energy storage power station according to the present invention. The present invention provides a power allocation method for an energy storage power station. In this embodiment, the energy storage power station includes multiple energy storage units, and the power allocation method includes the following steps:

[0093] Step S10: Determine the total power output of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit.

[0094] Step S20: Calculate the capacity weight coefficient overflow of each energy storage unit based on the power weight coefficient and the capacity weight coefficient of each energy storage unit.

[0095] The power weight coefficient Kpi is the proportion of the maximum rechargeable power Pci or maximum dischargeable power Pdi of the current energy storage unit to the sum of the maximum rechargeable power or maximum dischargeable power of all energy storage units. It represents the amount of power that can be allocated to the current energy storage unit when the total power P of the energy storage station is allocated according to the power weight. Correspondingly, the capacity weight coefficient Kci(1) is the proportion of the remaining available capacity of the current energy storage unit to the sum of the remaining available capacity of all energy storage units. It represents the amount of power that can be allocated to the current energy storage unit when the total power P of the energy storage station is allocated according to the capacity weight. The capacity weight coefficient overflow Skci(1) is the difference between the capacity weight coefficient Kci(1) and the power weight coefficient Kpi. It represents the part of the capacity weight that exceeds the power weight. Correspondingly, the total capacity weight coefficient overflow Skcn(1) is the sum of the capacity weight coefficient overflow Skci(1) of all energy storage units. It is the overflow capacity weight coefficient that needs to be corrected.

[0096] Step S30: If any of the capacity weight coefficient overflows is not 0, calculate the capacity weight coefficient correction amount, new capacity weight coefficient and new capacity weight coefficient overflow of each energy storage unit based on the capacity weight coefficient overflow of each energy storage unit, the remaining available capacity of each energy storage unit, the capacity weight coefficient and the power weight coefficient, until any of the new capacity weight coefficient overflows is 0.

[0097] Step S40: Distribute the total output power of the energy storage power station to each energy storage unit according to the capacity weight coefficient when the overflow amount is 0.

[0098] If the total capacity weight coefficient overflow Skcn(1) is 0, it means that there is no overflow in any energy storage unit of the energy storage power station. That is, the capacity weight coefficient Kci(1) of all energy storage units is less than or equal to the power weight coefficient Kpi. The total power output P of the energy storage power station can be directly allocated to each energy storage unit according to the capacity weight coefficient Kci(1) to achieve the balance between the remaining capacity of the energy storage unit and the power allocation, so that the SOC of each energy storage unit tends to be consistent. At this time, the power output Pi allocated to each energy storage unit is equal to the total power output P * the capacity weight coefficient Kci(1) of the energy storage unit.

[0099] If the total capacity weight coefficient overflow Skcn(1) is not 0, it indicates that there are overflowing energy storage units in the energy storage power station, that is, there is a certain energy storage unit whose capacity weight coefficient Kci(1) is greater than the power weight coefficient Kpi. Directly allocating the total power P of the energy storage power station to each energy storage unit according to the capacity weight coefficient Kci(1) can achieve the balance between the remaining capacity of the energy storage unit and the power allocation, and make the SOC of each energy storage unit more consistent. However, some energy storage units will not be able to fully respond to the power command, which will eventually cause the actual response power of the entire energy storage power station to deviate from the total power. Therefore, it is necessary to further determine the new capacity weight coefficient Kci(2) of each energy storage unit according to the correction amount Rkci(1) of the capacity weight coefficient of each energy storage unit, and obtain the new capacity weight coefficient overflow amount Skci(2) of each energy storage unit after correction and the total new capacity weight coefficient overflow amount Skcn(2) of all energy storage units. If the total overflow of the new capacity weight coefficient Skcn(2) is 0, then the total power P of the energy storage power station is allocated to each energy storage unit according to the new capacity weight coefficient Kci(2). Otherwise, continue to determine the new capacity weight coefficient Kci(3) of each energy storage unit according to the correction amount Rkci(2) of the new capacity weight coefficient of each energy storage unit, and repeat the step of obtaining the capacity weight coefficient after correction until the new capacity weight coefficient Kci(N) is calculated and the total overflow of the new capacity weight coefficient Skcn(N) is 0.

[0100] In this embodiment, the total output power of the energy storage power station, the power weight coefficient of each energy storage unit, and the capacity weight coefficient of each energy storage unit are determined. Based on the power weight coefficient and capacity weight coefficient of each energy storage unit, the capacity weight coefficient overflow of each energy storage unit is calculated. If any capacity weight coefficient overflow is not zero, based on the capacity weight coefficient overflow, the remaining available capacity of each energy storage unit, the capacity weight coefficient, and the power weight coefficient, the capacity weight coefficient correction amount, a new capacity weight coefficient, and a new capacity weight coefficient overflow of each energy storage unit are calculated until any new capacity weight coefficient overflow is zero. The total output power of the energy storage power station is allocated to each energy storage unit according to the capacity weight coefficient when the capacity weight coefficient overflow is zero.

[0101] First, based on the power weight coefficient Kpi and capacity weight coefficient Kci(1) of each energy storage unit, determine the capacity weight coefficient overflow Skci(1) of each energy storage unit and the total capacity weight coefficient overflow Skcn(1) of all energy storage units; then, if the total capacity weight coefficient overflow Skcn(1) is 0, the total power output P of the energy storage power station is directly allocated to each energy storage unit according to the capacity weight coefficient Kci(1); if the total capacity weight coefficient overflow Skcn(1) is not 0, it means that if the total power output P of the energy storage power station is directly allocated to each energy storage unit according to the capacity weight coefficient Kci(1), the total capacity weight coefficient overflow Skcn(1) is not 0. If i(1) is allocated to each energy storage unit, some energy storage units will not be able to fully respond to the power command, which will eventually cause the actual response power of the entire energy storage power station to deviate from the total issued power P. Therefore, it is necessary to evenly allocate the overflow of the overflow unit to the non-overflow unit. The new capacity weight coefficient Kci(2) of each energy storage unit is determined by the capacity weight coefficient correction amount Rkci(1) of each energy storage unit, and the capacity weight coefficient overflow amount Skci(2) of each energy storage unit and the total capacity weight coefficient overflow amount Skcn(2) of all energy storage units are re-determined until the new capacity weight coefficient Kci(N) is calculated and the new capacity weight coefficient overflow amount Skcn(N) is 0. Finally, the balance between the remaining capacity and power allocation of the energy storage unit is achieved, so that the SOC of each energy storage unit is balanced.

[0102] By comprehensively considering the actual usable capacity and SOC deviation of the energy storage units, the total output power is rationally allocated to make the SOC of each energy storage unit more consistent. This solves the problem of accurately and rationally allocating power to the energy storage units of the energy storage power station, avoids the deviation between the total output power and the actual response power of the energy storage system as a whole, thereby reducing the waste of energy storage power station capacity and extending the overall operating life of the energy storage power station.

[0103] Furthermore, in another embodiment of the power allocation method for an energy storage power station provided by the present invention, the step of determining the total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit includes:

[0104] Obtain the total power demand of the energy storage power station, the maximum rechargeable power, the maximum dischargeable power, and the remaining available capacity of each energy storage unit;

[0105] The total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit are calculated based on the total power demand of the energy storage power station and the maximum rechargeable power, maximum dischargeable power, and remaining available capacity of each energy storage unit.

[0106] The charging power is represented by a negative value, and the discharging power is represented by a positive value.

[0107] The power values ​​mentioned below all follow the principle of negative charging and positive discharging, that is, negative values ​​represent charging power and positive values ​​represent discharging power. The steps below will not be repeated. The total power demand can be active power or reactive power. The input or output of active power and reactive power can ultimately be realized by the PCS (Power Conversion System) in the energy storage unit.

[0108] The total power demand of an energy storage power station may come from the target power value directly issued by the superior authority, or it may come from non-power parameters obtained from the grid connection point, key connection point or other power protection and control devices of the energy storage power station, and then be converted into the target power value after judgment and calculation.

[0109] Optionally, the step of calculating the total power output of the energy storage power station includes:

[0110] When the total demand power of the energy storage power station is equal to the charging power, the maximum rechargeable power of each energy storage unit is summed to obtain the total maximum rechargeable power value, and the larger value of the total demand power and the total maximum rechargeable power value is determined as the total output power of the energy storage power station.

[0111] When the total demand power of the energy storage power station is equal to the discharge power, the maximum dischargeable power of each energy storage unit is summed to obtain the total maximum dischargeable power value, and the smaller value between the total demand power and the total maximum dischargeable power value is determined as the total output power of the energy storage power station.

[0112] ① If the total demand power Pn < 0, then select all energy storage units with maximum rechargeable power Pci ≠ 0, determine the value of the maximum rechargeable power Pci of each of these energy storage units, and then sum up the maximum rechargeable power Pci of each energy storage unit to obtain the total maximum rechargeable power value Pci n.

[0113] ② If the total power demand Pn > 0, then select all energy storage units with maximum discharge power Pdi ≠ 0, determine the value of the maximum discharge power Pdi of each of these energy storage units, and then sum up the maximum discharge power Pdi of each energy storage unit to obtain the total maximum rechargeable power Pd in.

[0114] ③ If the total demand power Pn = 0, then directly set the output power of all energy storage units to 0 and continue to wait to receive the new total demand power.

[0115] Among them, the energy storage unit may have its maximum rechargeable power Pc i = 0 or its maximum dischargeable power Pd i = 0 due to reasons such as fault, offline, or exceeding the SOC limit.

[0116] If the total demand power Pn exceeds the current maximum charging / discharging capacity of the energy storage station, then the current maximum charging / discharging capacity is used as the total output power P; if the total demand power Pn does not exceed the current maximum charging / discharging capacity of the energy storage station, then the total demand power Pn is used as the total output power P. The specific calculation method is as follows:

[0117] ① If the total demand power Pn < 0, then the total output power P = Max(total demand power Pn, total maximum rechargeable power Pci n). That is, if the total demand for the energy storage station is the charging demand, then the value of the total output power P is equal to the smaller absolute value between the total demand power Pn and the total maximum rechargeable power Pc in.

[0118] ② If the total demand power Pn > 0, then the total output power P = Mi n (total demand power Pn, maximum dischargeable power combined Pd in). That is, if the total demand for the energy storage power station is the discharge demand, then the value of the total output power P is equal to the smaller value between the total demand power Pn and the maximum dischargeable power combined Pc in.

[0119] Optionally, the step of obtaining the remaining available capacity of each of the energy storage units includes:

[0120] When the total demand power of the energy storage power station is the charging power, determine the upper limit of the state of charge of the battery in each energy storage unit and the first charge difference of the current state of charge, and determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the first charge difference.

[0121] When the total demand power of the energy storage power station is the discharge power, determine the current state of charge of the battery in each energy storage unit and the second charge difference value of the state of charge limit. Determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the second charge difference value.

[0122] Determine the current state of charge (SOCi) of each energy storage unit;

[0123] Determine the rated capacity Cei of the batteries in each energy storage unit;

[0124] ① If the total demand power Pn < 0, then determine the upper limit of SOC SOChi of each energy storage unit, determine the remaining rechargeable SOC of each energy storage unit = upper limit of SOC SOChi of each energy storage unit - current state of charge SOCi, and the remaining usable capacity Cri of the energy storage unit = rated capacity Cei × remaining rechargeable SOC.

[0125] ② If the total demand power Pn>0, then determine the lower limit of SOC li for each energy storage unit, and determine the remaining dischargeable SOC of each energy storage unit = current state of charge SOCi - lower limit of SOC li for each energy storage unit, and the remaining usable capacity Cri of the energy storage unit = rated capacity Cei × remaining dischargeable SOC.

[0126] To achieve a balanced SOC (State of Charge) across all energy storage units, the standard for calculating the remaining rechargeable SOC or remaining dischargeable SOC of each unit should be consistent. Specifically, the upper limit SOC (SOChi) or lower limit SOC (SOCLi) of each unit should be the same. Since the types, specifications, manufacturing processes, and operating environments of the batteries in each energy storage unit may differ, the charging cutoff SOC (to prevent overcharging) or discharging cutoff SOC (to prevent over-discharging) may vary. However, these differences will not affect the accuracy of the calculation steps and results of this invention. Energy storage units that have reached their charging or discharging cutoff SOC will have their maximum rechargeable power or maximum dischargeable power reach 0 due to exceeding the SOC limit, thus receiving protection. Energy storage units with a maximum rechargeable power of 0 will not participate in the allocation of charging power, and those with a maximum dischargeable power of 0 will not participate in the allocation of discharging power.

[0127] When calculating the remaining usable capacity Ci of each energy storage unit, it is not required that each energy storage unit have a consistent rated battery capacity Cei. The different rated battery capacities Cei between different energy storage units will not affect the correctness of the calculation steps and results of this invention.

[0128] Optionally, the step of calculating the power weighting coefficient of each of the energy storage units includes:

[0129] When the total power demand of the energy storage power station is the charging power, the ratio of the maximum rechargeable power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0130] When the total power demand of an energy storage power station is equal to the discharge power, the ratio of the maximum discharge power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

[0131] The power weighting coefficient Kpi of an energy storage unit refers to the ratio between the maximum rechargeable power Pci or the maximum dischargeable power Pdi of the energy storage unit and the total output power P of the energy storage power station. When the total output power P of the energy storage power station is the charging power expressed as a negative value, then the power weighting coefficient Kpi of the energy storage unit = the maximum rechargeable power Pci of the energy storage unit / the total output power P of the energy storage power station; correspondingly, when the total output power P of the energy storage power station is the discharge power expressed as a positive value, then the power weighting coefficient Kpi of the energy storage unit = the maximum dischargeable power Pdi of the energy storage unit / the total output power P of the energy storage power station. It should be noted that when the maximum rechargeable power Pci or the maximum dischargeable power Pdi of the energy storage unit remains unchanged, and the total output power P of the energy storage power station also remains unchanged, the power weighting coefficient Kpi of each energy storage unit is a constant value in subsequent steps.

[0132] Optionally, the step of calculating the capacity weighting coefficient of each of the energy storage units includes:

[0133] The total remaining available capacity is obtained by summing up the remaining available capacity of each energy storage unit;

[0134] The capacity weighting coefficient of each energy storage unit is determined based on the remaining available capacity of each energy storage unit and the total remaining available capacity.

[0135] The capacity weighting coefficient Kci(1) of a certain energy storage unit refers to the ratio between the remaining available capacity Cri of a certain energy storage unit and the total remaining available capacity Crn(1) of all energy storage units. The remaining available capacity Cri of each energy storage unit in the energy storage power station is summed to obtain the total remaining available capacity Crn(1) of all energy storage units. The capacity weighting coefficient Kci(1) of each energy storage unit is determined as: remaining available capacity Cri / total remaining available capacity Crn(1).

[0136] Furthermore, in another embodiment of the power allocation method for an energy storage power station provided by the present invention, the step of calculating the capacity weighting coefficient overflow of each energy storage unit includes:

[0137] Determine the weighting coefficient difference between the capacity weighting coefficient and the power weighting coefficient for each energy storage unit;

[0138] When the difference in the weighting coefficients is greater than 0, the overflow amount of the capacity weighting coefficients is determined to be the difference in the weighting coefficients.

[0139] When the difference in the weighting coefficients is less than or equal to 0, the overflow amount of the capacity weighting coefficient is determined to be 0.

[0140] The difference between the capacity weight coefficient Kci(1) and the power weight coefficient Kpi is determined. If the difference is greater than 0, the capacity weight coefficient overflow Skci(1) of the energy storage unit is the difference in weight coefficients. If the difference is less than or equal to 0, the capacity weight coefficient overflow Skci(1) of the energy storage unit is 0. The total capacity weight coefficient overflow Skcn(1) is obtained by summing the capacity weight coefficient overflow Skci(1) of all energy storage units in the energy storage power station.

[0141] Furthermore, in another embodiment of the power allocation method for an energy storage power station provided by the present invention, the step of calculating the capacity weighting coefficient correction amount of each energy storage unit includes:

[0142] When the capacity weight coefficient overflow is greater than 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be an overflow unit, and the capacity weight coefficient correction amount of the overflow unit is determined to be 0.

[0143] When the capacity weight coefficient overflow is equal to 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be a non-overflow unit; the capacity weight coefficient overflow of each energy storage unit is summarized to obtain the total capacity weight coefficient overflow; the remaining available capacity of each non-overflow unit is summarized to obtain the total remaining available capacity of the non-overflow units; and the capacity weight coefficient correction amount of the non-overflow unit is calculated based on the remaining available capacity of each non-overflow unit, the total remaining available capacity, and the total capacity weight coefficient overflow.

[0144] ①If the capacity weight coefficient overflow amount Skci(1) of a certain energy storage unit i is greater than 0, then the energy storage unit is determined to be an overflow unit, and the capacity weight coefficient correction amount Rkci(1) of the overflow unit is determined to be 0.

[0145] Optionally, the step of calculating the capacity weighting coefficient correction amount of the non-overflow unit includes:

[0146] The ratio of the remaining available capacity of each non-overflow unit to the total remaining available capacity is multiplied by the total overflow amount of the capacity weight coefficient, and the result is used as the correction amount of the capacity weight coefficient of each non-overflow unit.

[0147] ② If the capacity weight coefficient overflow amount Skc i(1) of a certain energy storage unit i is 0, then the energy storage unit is determined to be a non-overflow unit, and the capacity weight coefficient correction amount Rkci(1) of the non-overflow unit is determined according to the remaining available capacity Cri of the non-overflow unit, the total remaining available capacity Crn(2) of all non-overflow units, and the total capacity weight coefficient overflow amount Skcn(1); the capacity weight coefficient correction amount Rkci(1) of the non-overflow unit = the remaining available capacity Cri of the non-overflow unit / the total remaining available capacity Crn(2) of all non-overflow units × the total capacity weight coefficient overflow amount Skcn(1).

[0148] Furthermore, in another embodiment of the power allocation method for an energy storage power station provided by the present invention, the step of calculating the capacity weighting coefficient correction amount of the non-overflow unit includes:

[0149] The ratio of the remaining available capacity of each non-overflow unit to the total remaining available capacity is multiplied by the total overflow amount of the capacity weight coefficient, and the result is used as the correction amount of the capacity weight coefficient of each non-overflow unit.

[0150] Optionally, the step of calculating the new capacity weighting coefficient for each energy storage unit includes:

[0151] The difference between the capacity weight coefficient and the overflow amount of the capacity weight coefficient for each energy storage unit, plus the correction amount of the capacity weight coefficient, is used as the new capacity weight coefficient for each energy storage unit.

[0152] When determining the new capacity weight coefficient Kci(2) of each energy storage unit based on the capacity weight coefficient correction amount Rkci(1), the difference between the capacity weight coefficient Kci(1) and the capacity weight coefficient overflow amount Skci(1) of each energy storage unit, plus the capacity weight coefficient correction amount Rkci(1), is used as the new capacity weight coefficient Kci(2) of each energy storage unit.

[0153] Therefore, the new capacity weighting coefficient Kci(2) of the energy storage unit is equal to the capacity weighting coefficient Kci(1) of the energy storage unit - the capacity weighting coefficient overflow Skci(1) + the capacity weighting coefficient correction amount Rkci(1). In other words, for the energy storage unit with the capacity weighting coefficient overflow Skci(1) > 0, the new capacity weighting coefficient Kci(2) is equal to the power weighting coefficient Kpi; for the energy storage unit with the capacity weighting coefficient overflow Skci(1) = 0, the new capacity weighting coefficient Kci(2) is equal to the capacity weighting coefficient Kci(1) + the capacity weighting coefficient correction amount Rkci(1).

[0154] For the overflow unit, the new capacity weight coefficient Kci(2) is its power weight coefficient Kpi, so after the first round of correction, the overflow unit becomes a non-overflow unit.

[0155] For non-overflow units, the new capacity weight coefficient Kci(2) is based on its capacity weight coefficient Kci(1) with the addition of the capacity weight coefficient correction amount Rkci(1). At this time, the new capacity weight coefficient Kci(2) of the non-overflow unit may be greater than its power weight coefficient Kpi, or it may still be less than its power weight coefficient Kpi. That is to say, after the first round of correction, it may become an overflow unit or it may still be a non-overflow unit.

[0156] After the first round of correction, the total overflow of capacity weight coefficient Skcn(1) is allocated among the non-overflow units according to the ratio of the remaining available capacity Cri of the non-overflow units to the total remaining available capacity Crn(2) of all the non-overflow units. Then, new overflow units and new non-overflow units are determined, and the above allocation process is repeated for subsequent rounds of correction until a new capacity weight coefficient Kci(N) is calculated and the total overflow of the new capacity weight coefficient Skcn(N) is 0.

[0157] Based on the above embodiments, referring to Figure 3 According to Table 1, in an application example of the power allocation method of an energy storage power station of the present invention, the energy storage power station comprehensively considers the actual available capacity of the energy storage units and the SOC deviation between each energy storage unit, and rationally allocates the total output power so that the SOC of each energy storage unit tends to be consistent. This solves the problem of difficulty in accurately and rationally allocating power to the energy storage units of the energy storage power station, avoids the deviation between the total output power and the actual response power of the overall energy storage system, thereby reducing the waste of energy storage power station capacity and extending the overall operating life of the energy storage power station.

[0158] 1. Confirm the total required power Pn (negative charging, positive discharging)

[0159] The total power demand may come from the target power value directly issued by the superior authority, or it may be non-power parameters obtained from the grid connection point of the energy storage power station, key connection point or other power protection and control devices. It needs to be judged and calculated before it can be converted into the target power value.

[0160] 2. Determine the sign of the total power demand Pn

[0161] ① If the total demand power Pn < 0, then all energy storage units with maximum rechargeable power Pci ≠ 0 are screened out, and the value of the maximum rechargeable power Pci of each of these energy storage units is determined. Then proceed to step 3. Subsequent steps only involve these screened energy storage units, that is, energy storage units with maximum rechargeable power Pci = 0 are no longer involved in subsequent steps.

[0162] ② If the total demand power Pn > 0, then all energy storage units with maximum discharge power Pdi ≠ 0 are screened out, and the value of the maximum discharge power Pdi of each of these energy storage units is determined. Then proceed to step 3. Subsequent steps only involve the screened energy storage units, that is, energy storage units with maximum discharge power Pdi = 0 are no longer involved in subsequent steps.

[0163] ③ If the total power demand Pn = 0, then directly set the power of all energy storage units to 0 and return to step 1.

[0164] 3. Determine the current state of charge (SOCi) of the batteries in each energy storage unit.

[0165] 4. Determine the sign of the total power demand Pn

[0166] ① If the total power demand Pn < 0, then determine the upper limit of SOC SOChi for each energy storage unit.

[0167] ② If the total power demand Pn > 0, then determine the lower limit of SOC for each energy storage unit, SOC li.

[0168] 5. Determine the rated capacity Cei of the batteries in each energy storage unit.

[0169] 6. Determine the sign of the total power demand Pn

[0170] ①If the total power demand Pn < 0, then the maximum rechargeable power Pci of each energy storage unit is summed to obtain the total maximum rechargeable power Pci n.

[0171] ②If the total power demand Pn>0, then the maximum dischargeable power Pd i of each energy storage unit is summed to obtain the total maximum dischargeable power Pd in;

[0172] 7. Calculate the total power output P. If the total power demand Pn exceeds the current maximum charging / discharging capacity of the energy storage station, then the current maximum charging / discharging capacity is used as the total power output P; if the total power demand Pn does not exceed the current maximum charging / discharging capacity of the energy storage station, then the total power demand Pn is used as the total power output P. The specific calculation method is as follows:

[0173] ① If the total demand power Pn < 0, then the total output power P = Max(total demand power Pn, total maximum rechargeable power Pci n). That is, if the total demand for the energy storage station is the charging demand, then the value of the total output power P is equal to the smaller absolute value between the total demand power Pn and the total maximum rechargeable power Pc in.

[0174] ② If the total demand power Pn > 0, then the total output power P = Min (total demand power Pn, maximum dischargeable power combined Pd in). That is, if the total demand for the energy storage power station is the discharge demand, then the value of the total output power P is equal to the smaller value between the total demand power Pn and the maximum dischargeable power combined Pc in.

[0175] 8. Calculate the power weighting coefficient Kpi for each energy storage unit.

[0176] ①If the total power demand Pn < 0, then Kpi ​​= Pci / P;

[0177] ②If the total power demand Pn>0, then Kpi=Pd i / P;

[0178] 9. Calculate the remaining usable capacity Ci of the batteries in each energy storage unit.

[0179] ①If the total power demand Pn < 0, then Cri = rated capacity of the energy storage battery Cei * (SOChi - SOCi);

[0180] ②If the total power demand Pn>0, then Cri=rated capacity of energy storage battery Cei*(SOCi-SOC li);

[0181] 10. The sum of Cri yields the first-order total remaining available capacity Crn(1).

[0182] 11. Calculate the first-order capacity weighting coefficient Kci(1) for each energy storage unit, Kci(1)=Cr i / Crn(1)

[0183] 12. Calculate the overflow amount Skci(1) of the first-order capacity weighting coefficient for each energy storage unit. Skci(1) = the difference between the first-order capacity weighting coefficient Kci(1) and the power weighting coefficient Kpi, where the difference is greater than 0. If the difference is ≤ 0, then let Skci(1) = 0.

[0184] 13. The total overflow of the first-order capacity weight coefficient Skcn(1) is obtained by summing Skci(1).

[0185] 14. The remaining usable capacity Ci of the energy storage units whose first-order capacity weighting coefficient overflow Skci(1) = 0, i.e., whose first-order capacity weighting coefficient Kci(1) does not overflow, is summed to obtain the second-order total remaining usable capacity Crn(2).

[0186] 15. Calculate the first-order capacity weighting coefficient correction factor Rkci(1). The calculation principle is as follows:

[0187] ① If the overflow amount Skci(1) of the first-order capacity weight coefficient of a certain energy storage unit i is greater than 0, that is, the first-order capacity weight coefficient Kci(1) overflows, then the first-order capacity weight coefficient correction amount Rkci(1) of the energy storage unit is 0.

[0188] ② If the overflow amount Skci(1) of the first-order capacity weight coefficient of a certain energy storage unit i is 0, that is, the first-order capacity weight coefficient Kci(1) does not overflow, then the first-order capacity weight coefficient correction amount Rkci(1) of the energy storage unit is Cr i / Crn(2)*Skcn(1).

[0189] 16. Calculate the second-order capacity weighting coefficient Kci(2) for each energy storage unit.

[0190] Kci(2)=Kci(1)-Skci(1)+Rkci(1)

[0191] 17. Calculate the overflow amount Skci(2) of the second-order capacity weighting coefficient for each energy storage unit. Skci(2) = the difference between the second-order capacity weighting coefficient Kci(2) and the power weighting coefficient Kpi, where the difference is greater than 0. If the difference is ≤ 0, then let Skci(2) = 0.

[0192] 18. The summation of Skci(2) yields the total overflow of the second-order capacity weight coefficient Skcn(2).

[0193] ①If Skcn(2)=0, then proceed to step 19;

[0194] ② If Skcn(2) > 0, repeat steps 14 to 18, and calculate the third-order capacity weight coefficient Kci(3) / third-order capacity weight coefficient overflow Skci(3) / third-order capacity weight coefficient overflow Skcn(3) according to the method of calculating the second-order capacity weight coefficient overflow Skcn(2), the fourth-order capacity weight coefficient Kci(4) / fourth-order capacity weight coefficient overflow Skci(4) / fourth-order capacity weight coefficient overflow Skcn(4) ... N-order capacity weight coefficient Kci(N) / N-order capacity weight coefficient overflow Skci(N) / N-order capacity weight coefficient overflow Skcn(N) until Skcn(N) = 0, and then proceed to step 19;

[0195] The specific calculation method for data of order (N-1) to N (N>1) is as follows:

[0196] 18.1 We obtain the (N-1)th order capacity weight coefficient Kci(N-1), the (N-1)th order capacity weight coefficient overflow Skci(N-1), and the (N-1)th order capacity weight coefficient overflow total Skcn(N-1);

[0197] 18.2 The remaining usable battery capacity Cra of all (N-1) order capacity weight coefficient overflow Skci(N-1) = 0, that is, the remaining usable battery capacity Crn(N) of the energy storage unit whose (N-1) order capacity weight coefficient Kci(N-1) does not overflow is summed to obtain the total remaining usable capacity Crn(N) of the Nth order.

[0198] 18.3 Calculate the (N-1)th order capacity weighting coefficient correction factor Rkci(N-1), the calculation principle is as follows:

[0199] ① If the overflow amount Skci(N-1) of the (N-1)th order capacity weight coefficient of a certain energy storage unit is greater than 0, that is, the overflow of the (N-1)th order capacity weight coefficient Kci(N-1), then the correction amount Rkci(N-1) of the (N-1)th order capacity weight coefficient of the energy storage unit is 0.

[0200] ② If the overflow amount Skci(N-1) of the (N-1)th order capacity weight coefficient of a certain energy storage unit is 0, that is, the (N-1)th order capacity weight coefficient Kci(N-1) does not overflow, then the correction amount Rkci(N-1) of the (N-1)th order capacity weight coefficient of the energy storage unit is Cri / Crn(N)*Skcn(N-1);

[0201] 18.4 Calculate the Nth-order capacity weighting coefficient Kci(N) for each energy storage unit, Kci(N)=Kci(N-1)-Skci(N-1)+Rkci(N-1);

[0202] 18.5 Calculate the overflow amount Skci(N) of the second-order capacity weighting coefficient for each energy storage unit. Skci(N) = N-order capacity weighting coefficient Kci(N) - power weighting coefficient Kpi and the difference that is greater than 0. If the difference is ≤ 0, then let Skci(N) = 0.

[0203] 18.6Skci(N) sums to obtain the total overflow of the Nth-order capacity weight coefficient Skcn(N);

[0204] 19. Calculate the power Pi to be transmitted to each energy storage unit, Pi = P * Kci(N), where P is the total transmitted power, and Kci(N) is the Nth-order capacity weighting coefficient satisfying Skcn(N) = 0. Then, transmit power commands to each energy storage unit according to the calculation results.

[0205]

[0206]

[0207] Table 1

[0208] Furthermore, embodiments of the present invention also provide a power distribution device for an energy storage power station, the power distribution device for the energy storage power station comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the power distribution method for the energy storage power station as described above.

[0209] Furthermore, this embodiment of the invention also provides an energy storage power station, which includes the power distribution device as described above and a plurality of energy storage units connected to the power distribution device, wherein the power distribution device distributes the total power output of the energy storage power station to each of the energy storage units.

[0210] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0211] 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.

[0212] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they 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) as described above, 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 described in the various embodiments of the present invention.

[0213] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A power distribution method for an energy storage power station, characterized in that, The energy storage power station includes multiple energy storage units, and the power distribution method of the energy storage power station includes the following steps: Determine the total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit; The capacity weight coefficient overflow of each energy storage unit is calculated based on the power weight coefficient and the capacity weight coefficient of each energy storage unit. If any of the capacity weight coefficients overflows, calculate the capacity weight coefficient correction amount, the new capacity weight coefficient, and the new capacity weight coefficient overflow for each energy storage unit until any of the new capacity weight coefficients overflows. The total output power of the energy storage power station is allocated to each energy storage unit according to the capacity weight coefficient when the overflow amount of the capacity weight coefficient is 0. The step of calculating the capacity weighting coefficient correction amount for each energy storage unit includes: When the capacity weight coefficient overflow is greater than 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be an overflow unit, and the capacity weight coefficient correction amount of the overflow unit is determined to be 0. When the capacity weight coefficient overflow is equal to 0, the energy storage unit corresponding to the capacity weight coefficient overflow is determined to be a non-overflow unit; the capacity weight coefficient overflow of each energy storage unit is summarized to obtain the total capacity weight coefficient overflow; the remaining available capacity of each non-overflow unit is summarized to obtain the total remaining available capacity of the non-overflow units; and the capacity weight coefficient correction amount of the non-overflow unit is calculated based on the remaining available capacity of each non-overflow unit, the total remaining available capacity, and the total capacity weight coefficient overflow.

2. The power allocation method for an energy storage power station as described in claim 1, characterized in that, The steps for determining the total power output of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit include: Obtain the total power demand of the energy storage power station, the maximum rechargeable power, the maximum dischargeable power, and the remaining available capacity of each energy storage unit; The total output power of the energy storage power station, the power weighting coefficient of each energy storage unit, and the capacity weighting coefficient of each energy storage unit are calculated based on the total power demand of the energy storage power station and the maximum rechargeable power, maximum dischargeable power, and remaining available capacity of each energy storage unit. The charging power is represented by a negative value, and the discharging power is represented by a positive value.

3. The power allocation method for an energy storage power station as described in claim 2, characterized in that, The step of calculating the total power output of the energy storage power station includes: When the total demand power of the energy storage power station is equal to the charging power, the maximum rechargeable power of each energy storage unit is summed to obtain the total maximum rechargeable power value, and the larger value of the total demand power and the total maximum rechargeable power value is determined as the total output power of the energy storage power station. When the total demand power of the energy storage power station is equal to the discharge power, the maximum dischargeable power of each energy storage unit is summed to obtain the total maximum dischargeable power value, and the smaller value between the total demand power and the total maximum dischargeable power value is determined as the total output power of the energy storage power station.

4. The power allocation method for an energy storage power station as described in claim 2, characterized in that, The step of obtaining the remaining available capacity of each of the energy storage units includes: When the total demand power of the energy storage power station is the charging power, determine the upper limit of the state of charge of the battery in each energy storage unit and the first charge difference of the current state of charge, and determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the first charge difference. When the total demand power of the energy storage power station is the discharge power, determine the current state of charge of the battery in each energy storage unit and the second charge difference value of the state of charge limit. Determine the remaining available capacity of each energy storage unit based on the rated capacity of the battery in each energy storage unit and the second charge difference value.

5. The power allocation method for an energy storage power station as described in claim 2, characterized in that, The step of calculating the power weighting coefficient of each of the energy storage units includes: When the total power demand of the energy storage power station is the charging power, the ratio of the maximum rechargeable power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit. When the total power demand of an energy storage power station is equal to the discharge power, the ratio of the maximum discharge power of each energy storage unit to the total output power is determined as the power weighting coefficient of each energy storage unit.

6. The power allocation method for an energy storage power station as described in claim 2, characterized in that, The step of calculating the capacity weighting coefficient of each of the energy storage units includes: The total remaining available capacity is obtained by summing up the remaining available capacity of each energy storage unit; The capacity weighting coefficient of each energy storage unit is determined based on the remaining available capacity of each energy storage unit and the total remaining available capacity.

7. The power allocation method for an energy storage power station as described in claim 1, characterized in that, The step of calculating the capacity weighting coefficient overflow of each energy storage unit includes: Determine the weighting coefficient difference between the capacity weighting coefficient and the power weighting coefficient for each energy storage unit; When the difference in the weighting coefficients is greater than 0, the overflow amount of the capacity weighting coefficients is determined to be the difference in the weighting coefficients. When the difference in the weighting coefficients is less than or equal to 0, the overflow amount of the capacity weighting coefficient is determined to be 0.

8. The power allocation method for an energy storage power station as described in claim 1, characterized in that, The step of calculating the capacity weighting coefficient correction amount of the non-overflow unit includes: The ratio of the remaining available capacity of each non-overflow unit to the total remaining available capacity is multiplied by the total overflow amount of the capacity weight coefficient, and the result is used as the correction amount of the capacity weight coefficient of each non-overflow unit.

9. The power allocation method for an energy storage power station as described in claim 1, characterized in that, The step of calculating the new capacity weighting coefficient for each energy storage unit includes: The difference between the capacity weight coefficient and the overflow amount of the capacity weight coefficient for each energy storage unit, plus the correction amount of the capacity weight coefficient, is used as the new capacity weight coefficient for each energy storage unit.

10. A power distribution device for an energy storage power station, characterized in that, The power distribution device of the energy storage power station includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the power distribution method of the energy storage power station as described in any one of claims 1 to 9.

11. An energy storage power station, characterized in that, The energy storage power station includes the power distribution device as described in claim 10 and a plurality of energy storage units connected to the power distribution device, wherein the power distribution device distributes the total power output of the energy storage power station to each of the energy storage units.

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