A method and system for selecting the capacity of a supercapacitor and lithium battery hybrid energy storage system

Abstract

This invention discloses a method for selecting the capacity of a hybrid energy storage system using supercapacitors and lithium batteries, comprising: data initialization; determining the power reference value for the current cycle; calculating the SOC of the supercapacitor and lithium battery against the power reference value for the current cycle; and calculating the MPFR. 10 Smooth demand and settle accounts based on the power baseline value for this cycle; calculate the difference d between the actual turbine output and the power baseline value selected in the first capacity calculation; determine whether the system is in the charging or discharging range; settle the SOC value from the previous cycle; calculate the MPFR value for the current cycle. 10 The calculation process includes: calculating the wind power stabilization effect; determining time t; calculating the charging and discharging power, grid-connected power, and SOC at each moment, and calculating whether there is load shedding or wind curtailment; starting the calculation of the supercapacitor SOC demand settlement value for the next cycle; calculating the average wind power output of this cycle as the benchmark value for the next cycle; determining time T; and selecting different supercapacitor values ​​for repeated operation. The corresponding system, electronic equipment, and computer-readable storage medium are also disclosed.

Description

Technical Field

[0001] This invention relates to the field of energy storage system technology, and in particular to a method and system for selecting the capacity of a hybrid energy storage system of supercapacitors and lithium batteries. Background Technology

[0002] With the increasing global overconsumption of fossil fuels and the growing environmental pollution, a new energy revolution characterized by the large-scale development and utilization of renewable energy and the rapid development of new energy sources has emerged. However, all of this relies on energy storage devices for energy conversion, storage, and utilization. Based on storage characteristics, energy storage devices are divided into energy-type energy storage technologies and power-type energy storage technologies. Energy-type energy storage devices mainly include lead-acid batteries, lithium-ion batteries, sodium-ion batteries, and flow batteries, while power-type energy storage devices mainly include flywheel energy storage, supercapacitors, and lithium-ion capacitors. Different energy-type energy storage devices have different technical parameters; however, single energy storage systems (ESS) still face key challenges such as the inability to simultaneously achieve high power density and high energy density, incompatibility between high-temperature and low-temperature performance, and a lack of coordination between operating rate and cycle life.

[0003] Batteries have two key parameters: energy density and power density. Energy density is the amount of energy a battery can store per kilogram of its weight; power density is the amount of energy a device can move during charging and discharging. Lithium-ion batteries have traditionally stored energy chemically and have been widely used due to their high energy density; however, they charge quite slowly. Supercapacitors, on the other hand, store energy statically rather than chemically. This means they can charge and discharge much faster without compromising their internal structure, resulting in very high power densities. However, this is offset by their significantly lower energy density compared to chemical batteries.

[0004] Hybrid energy storage systems (HESS) combining energy-type and power-type energy storage technologies are highly efficient systems for energy and power management. They fully leverage the durability of energy-type storage and the speed of power-type storage, significantly improving the overall performance and economy of energy storage systems. This provides an important solution for grid energy storage under complex operating conditions, particularly in applications involving power plants. This is because HESS can mitigate the fluctuations in wind energy, making the energy storage technology suitable for large-scale grid-connected renewable energy generation. Wind power generation consists of frequency components of varying amplitudes; since HESS incorporates both low-speed and high-speed responses, it achieves better smoothing compared to a single ESS.

[0005] However, there is no specific method in the existing technology for selecting the capacity of a hybrid energy storage system of supercapacitors and lithium batteries under dynamic grid connection, so as to extend the service life of lithium batteries, solve the problem of power fluctuation, ensure grid stability, and provide high-rate current for charging and discharging during the start-up and shutdown of new energy power plants or during large fluctuations in the grid. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides the following technical solution: a method for selecting the capacity of a hybrid energy storage system using supercapacitors and lithium batteries. This method selects the capacity of supercapacitors and lithium batteries based on real-time power generation data from the power station, achieving a reasonable allocation of capacity and simultaneously enabling the calculation of the cost per kilowatt-hour of energy storage, thereby reducing the energy storage cost of the hybrid energy storage system.

[0007] This invention provides a method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries, comprising:

[0008] S1, obtain real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of the supercapacitor and the lithium battery to a first threshold; setting the power reference value for the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle.

[0009] S2, use the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for this cycle;

[0010] S3 calculates the SOC of the supercapacitor and lithium battery against the power reference value for this cycle.

[0011] S4, Calculate MPFR 10 To stabilize demand and settle accounts based on the power baseline for this cycle;

[0012] S5, calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection, including: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand per second.

[0013] S6, determine whether the hybrid energy storage system is in the charging or discharging range by judging the positive or negative value of the difference d;

[0014] S7, to settle the supercapacitor and lithium battery SOC of the previous cycle;

[0015] S8, perform MPFR for the current cycle. 10 The settlement of the stabilization effect, the MPFR of the current period 10The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both of which maintain a fixed numerical compensation for each cycle.

[0016] S9, increment the current time by 1, let t = t + 1, and determine whether t has reached 60s. If it has reached 60s, return to step S5; otherwise, continue to step S10.

[0017] S10, after completing the settlement at each time point, calculate the charging and discharging power, grid-connected power, and SOC of the supercapacitor and lithium battery at each time point, and calculate whether there is any load shedding or wind curtailment at each time point.

[0018] S11, after a complete 60s cycle, the calculation of the supercapacitor SOC demand settlement value for the next cycle begins, and every ten complete cycles, the calculation of the lithium battery SOC demand settlement value for the next ten cycles is performed once.

[0019] S12, calculate the average wind power output for this cycle and use it as the benchmark value for the next cycle;

[0020] S13, increment the current period time T by 1, let T = T + 1, and determine whether T has reached T1. max If the value is not reached, return to step S2; if the value is reached, it means that the data at each moment has been calculated once, and the program for calculating the current supercapacitor value ends.

[0021] S14: Select different supercapacitor values ​​and repeat S1-S13 to determine the changes in the cost per kilowatt-hour of energy storage and the initial investment cost of the hybrid energy storage system.

[0022] Preferably, the first threshold is 50%.

[0023] Preferably, the second threshold is 0.8MW.

[0024] Preferably, the calculation of MPFR in S4 10 Stabilizing demand includes:

[0025] (1) Calculate the allowable range every ten minutes based on the MPFR tolerance per minute;

[0026] (2) Set up an array T with a maximum capacity of ten. d The baseline value for the first cycle of every ten cycles is input into array T before the start of the cycle. d In, T is defined d The maximum value in is a max The minimum value is a min ;

[0027] (3) Calculate the current benchmark value and amax and a min The relationship, if greater than a max Then calculate whether the difference between the current benchmark value and the minimum value exceeds the tolerance. If it does, the excess value is injected into the energy storage system, and the tolerance is used as the new 'a'. max If the tolerance limit is not exceeded, then this value will be used directly as a. max Less than a min The case is greater than a max The situation is the same;

[0028] (4) The baseline value after the above processing is used as the true baseline value for this period and is placed into T in sequence. d middle;

[0029] (5) The baseline value for the first period is directly entered into T. d In this process, the baseline value for each subsequent cycle needs to undergo the same operation until the tenth cycle is completed, at which point a new cycle begins.

[0030] Preferably, in step S6, when the device is in the charging range, the power grid charges the energy storage device, including:

[0031] (1) The amount of electricity that needs to be released by the grid is multiplied by the first coefficient to obtain the amount of electricity to be charged into the supercapacitor. That is, when charging from the grid to the energy storage device, a certain amount of energy needs to be lost; the first coefficient is 0.95.

[0032] (2) During charging, the supercapacitor is charged first, and then the lithium battery is charged. During each charging, a simulation calculation is performed on the supercapacitor data. If the SOC of the supercapacitor is still less than the maximum value requirement after charging the required amount of electricity, the charging is completed directly. If the SOC of the supercapacitor exceeds the maximum value requirement after charging the required amount of electricity, the SOC of the supercapacitor is set to the maximum value, and the remaining uncharged electricity is charged into the lithium battery. If the lithium battery is also at its maximum value at this time, the SOC of the lithium battery is set to the maximum value, and the excess electricity is returned to the grid as the electricity that cannot be consumed, thus completing the main part of the charging.

[0033] Preferably, in step S6, when in the discharge range, releasing energy from the energy storage device to the power grid includes:

[0034] (1) Multiply the amount of electricity in the supercapacitor by the second coefficient to obtain the amount of electricity released from the energy storage device to the grid. That is, when releasing electricity from the energy storage device to the grid, a certain amount of energy needs to be lost; the second coefficient is 0.95.

[0035] (2) Start the supercapacitor to discharge first. If the discharge is still insufficient to meet the power required by the grid, the lithium battery will be discharged. The power in the lithium battery will be multiplied by the third coefficient to obtain the power released by the energy storage device to the grid. That is, when the power is released from the energy storage device to the grid, a certain amount of energy needs to be lost. The third coefficient is 0.95.

[0036] Preferably, S7 includes:

[0037] S71 calculates the SOC of the supercapacitor, including: at the end of each cycle, calculating the difference between the supercapacitor's SOC and 50%. If the difference is positive, a fixed amount of electricity is discharged to the grid every second in the next cycle. If the electricity is insufficient, it is supplemented by the lithium battery. If both are insufficient, it is the portion that cannot be absorbed. If the difference is negative, a fixed amount of electricity is absorbed from the grid every second in the next cycle. The same applies when it is fully charged.

[0038] S72 calculates the SOC of the lithium battery, including: the total settlement value is calculated after the supercapacitor calculation, and the settlement is performed every ten cycles. The settlement rules and procedures are located in the same place as the supercapacitor.

[0039] A second aspect of the present invention provides a capacity selection system for a hybrid energy storage system combining supercapacitors and lithium batteries, comprising:

[0040] The data acquisition and initialization module is used to acquire real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of the supercapacitor and the lithium battery to a first threshold; setting the power reference value for the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle.

[0041] The cycle power reference value determination module is used to take the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for the current cycle.

[0042] The first settlement module is used to settle the SOC of the supercapacitor and lithium battery against the power reference value for this cycle.

[0043] The second settlement module is used to calculate MPFR. 10 To stabilize demand and settle accounts based on the power baseline for this cycle;

[0044] The energy storage demand calculation module is used to calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection. This includes: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand for each second.

[0045] The judgment module is used to determine whether the hybrid energy storage system is in the charging or discharging range by judging the positive or negative value of the difference d;

[0046] The third settlement module is used to settle the supercapacitor and lithium battery SOC of the previous cycle.

[0047] The fourth settlement module is used to perform MPFR for the current period. 10 The settlement of the stabilization effect, the MPFR of the current period 10 The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both of which maintain a fixed numerical compensation for each cycle.

[0048] The time point setting and judgment module is used to increment the current time point by 1, let t = t + 1, and judge whether t reaches 60s. If it reaches 60s, return to step S5; otherwise, continue to step S10.

[0049] The time-based calculation module is used to calculate the charging and discharging power, grid-connected power, and SOC of the supercapacitor and lithium battery at each time after completing the settlement at each time. It also calculates whether there is any load shedding or wind curtailment at each time.

[0050] The cycle calculation module starts calculating the supercapacitor SOC demand settlement value for the next cycle after a complete 60s cycle ends. Every ten complete cycles, it calculates the lithium battery SOC demand settlement value for the next ten cycles.

[0051] The next cycle benchmark value determination module is used to calculate the average wind power output of the current cycle and use it as the benchmark value for the next cycle.

[0052] The cycle time setting and judgment module is used to increment the current cycle time T by 1, let T = T + 1, and then determine whether T has reached T1. max If the value is not reached, return to step S2; if the value is reached, it means that the data at each moment has been calculated once, and the program for calculating the current supercapacitor value ends.

[0053] The supercapacitor value selection module is used to select different supercapacitor values ​​and repeatedly run S1-S13 to determine the cost per kilowatt-hour of energy storage and the changes in the initial investment cost of the hybrid energy storage system.

[0054] A third aspect of the present invention provides an electronic device including a processor and a memory, the memory storing a plurality of instructions, the processor being configured to read the instructions and execute the method as described in the first aspect.

[0055] A fourth aspect of the present invention provides a computer-readable storage medium storing a plurality of instructions which can be read by a processor and executed as described in the first aspect.

[0056] The present invention provides a method, system, and electronic device for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries, which has the following beneficial effects:

[0057] By combining real-time power generation data from the power station, the capacity of supercapacitors and lithium batteries can be selected to achieve a reasonable allocation of capacity. At the same time, the cost per kilowatt-hour of energy storage can be calculated, thereby reducing the energy storage cost of the hybrid energy storage system. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the capacity selection method for the hybrid energy storage system of supercapacitor and lithium battery described in this invention.

[0059] Figure 2 The schematic diagram of the capacity selection system for the hybrid energy storage system of supercapacitor and lithium battery provided by the present invention.

[0060] Figure 3 This is a schematic diagram of the structure of an embodiment of the electronic device provided by the present invention. Detailed Implementation

[0061] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0062] The method provided by this invention can be implemented in a terminal environment that may include one or more of the following components: a processor, a memory, and a display screen. The memory stores at least one instruction, which is loaded and executed by the processor to implement the method described in the following embodiments.

[0063] A processor may include one or more processing cores. The processor uses various interfaces and lines to connect various parts of the terminal, and performs various functions and processes data by running or executing instructions, programs, code sets or instruction sets stored in memory, and by calling data stored in memory.

[0064] Memory can include random access memory (RAM) or read-only memory (ROM). Memory can be used to store instructions, programs, code, code sets, or instructions.

[0065] The display screen is used to show the user interface of each application.

[0066] In addition, those skilled in the art will understand that the structure of the terminal described above does not constitute a limitation on the terminal. The terminal may include more or fewer components, or combine certain components, or have different component arrangements. For example, the terminal may also include radio frequency circuits, input units, sensors, audio circuits, power supplies, and other components, which will not be described in detail here.

[0067] Example 1

[0068] like Figure 1 As shown, this embodiment provides a method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries, including:

[0069] S1, obtain real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of both the supercapacitor and the lithium battery to a first threshold; setting the power reference value for the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle.

[0070] In a preferred embodiment, the first threshold is 50%, thereby ensuring that the supercapacitor and lithium battery are chargeable and dischargeable, and can be flexibly configured according to grid requirements. SOC stands for state of charge, representing the battery's state of charge, which is the available state of the remaining charge in the battery. It is generally expressed as a percentage, typically the ratio of the remaining charge in the battery to its nominal (rated) charge capacity. In this embodiment, the second threshold is 0.8 MW.

[0071] S2, use the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for this cycle;

[0072] S3 calculates the SOC of the supercapacitor and lithium battery against the power reference value for this cycle.

[0073] S4, Calculate MPFR 10 To stabilize demand and settle accounts based on the power baseline for this cycle;

[0074] In a preferred embodiment, the calculation of MPFR 10 Stabilizing demand includes:

[0075] (1) Calculate the allowable range every ten minutes based on the MPFR tolerance per minute;

[0076] (2) Set up an array T with a maximum capacity of ten. d The baseline value for the first cycle of every ten cycles is input into array T before the start of the cycle. d In, T is defined d The maximum value in is a max The minimum value is a min ;

[0077] (3) Calculate the current benchmark value and a max and a min The relationship, if greater than a max Then calculate whether the difference between the current benchmark value and the minimum value exceeds the tolerance. If it does, the excess value is injected into the energy storage system, and the tolerance is used as the new 'a'. max If the tolerance limit is not exceeded, then this value will be used directly as a. max Less than a min The case is greater than a max The situation is similar;

[0078] (4) The baseline value after the above processing is used as the true baseline value for this period and is placed into T in sequence. d This makes subsequent calculations easier.

[0079] (5) The above operation is not performed on the reference value of the first period, but it is directly put into T. d In the middle, the baseline value of each subsequent cycle needs to be processed in the same way, until the tenth cycle is completed, at which point a new cycle will begin.

[0080] It should be noted that this part of the procedure needs to be placed after the SOC's calculation procedure for the benchmark value.

[0081] S5, calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection, including: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand per second.

[0082] S6, determine whether the hybrid energy storage system is in the charging or discharging range by judging the positive or negative value of the difference d;

[0083] In this embodiment, when the device is in the charging range, the power grid charges the energy storage device, as analyzed below:

[0084] (1) The amount of electricity that needs to be released by the grid is multiplied by the first coefficient (in this embodiment, the first coefficient is set to 0.95) as the amount of electricity to be charged into the supercapacitor. That is, when charging from the grid to the energy storage device, a certain amount of energy (in this embodiment, 5%) needs to be lost, and only 95% of the energy is charged into the energy storage device.

[0085] (2) During charging, the supercapacitor is charged first, and then the lithium battery is charged. During each charging, a simulation calculation is performed on the supercapacitor data. If the SOC of the supercapacitor is still less than the maximum value requirement after charging the required amount of electricity, the charging is completed directly. If the SOC of the supercapacitor exceeds the maximum value requirement after charging the required amount of electricity, the SOC of the supercapacitor is set to the maximum value, and the remaining uncharged electricity is charged into the lithium battery. If the lithium battery is also at its maximum value at this time, the SOC of the lithium battery is set to the maximum value, and the excess electricity is returned to the grid as the electricity that cannot be consumed, thus completing the main part of the charging.

[0086] When in the discharge range, energy is released from the energy storage device back into the grid, as analyzed below:

[0087] (1) Multiply the amount of electricity in the supercapacitor by the second coefficient (in this embodiment, the second coefficient is set to 0.95) as the amount of electricity released from the energy storage device to the grid. That is, when the energy storage device releases electricity to the grid, a certain amount of energy (in this embodiment, 5%) needs to be lost. Only 95% of the energy is released from the energy storage device to the grid. There is also a 5% energy loss. Only 95% can be successfully charged into the grid.

[0088] (2) Start the supercapacitor to discharge first. If the discharge is still insufficient to meet the power required by the grid, the lithium battery will be discharged. The power in the lithium battery will be multiplied by the third coefficient (in this embodiment, the third coefficient is set to 0.95) as the power released by the energy storage device to the grid. That is, when the power is released from the energy storage device to the grid, a certain amount of energy (in this embodiment, 5%) needs to be lost. Only 95% of the energy is released from the energy storage device to the grid. There is also a 5% energy loss. Only 95% can be successfully charged into the grid.

[0089] S7 performs the SOC settlement for the previous cycle of supercapacitors and lithium batteries, including:

[0090] S71 calculates the SOC of the supercapacitor, including: at the end of each cycle, calculating the difference between the supercapacitor's SOC and 50%. If the difference is positive, a fixed amount of electricity is discharged to the grid every second in the next cycle. If the electricity is insufficient, it is supplemented by the lithium battery. If both are insufficient, it is the portion that cannot be absorbed. If the difference is negative, a fixed amount of electricity is absorbed from the grid every second in the next cycle. The same applies when it is fully charged.

[0091] S72, for the SOC of lithium battery, the calculation of total settlement value is performed after the supercapacitor calculation, and settlement is performed every ten cycles. The settlement rules and procedures are the same as those for supercapacitor.

[0092] S8, perform MPFR for the current cycle. 10The settlement of the stabilization effect, the MPFR of the current period 10 The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both maintaining a fixed numerical compensation for each cycle.

[0093] S9, increment the current time by 1, let t = t + 1, and determine whether t has reached 60s. If it has reached 60s, return to step S5; otherwise, continue to step S10.

[0094] S10, after completing the settlement at each time point, calculate the charging and discharging power, grid-connected power, and SOC of the supercapacitor and lithium battery at each time point, and calculate whether there is any load shedding or wind curtailment at each time point.

[0095] S11, after a complete 60s cycle, the calculation of the supercapacitor SOC demand settlement value for the next cycle begins, and every ten complete cycles, the calculation of the lithium battery SOC demand settlement value for the next ten cycles is performed once.

[0096] S12, calculate the average wind power output for this cycle and use it as the benchmark value for the next cycle;

[0097] S13, increment the current period time T by 1, let T = T + 1, and determine whether T has reached T1. max If the value is not reached, return to step S2; if the value is reached, it means that the data at each moment has been calculated once, and the program for calculating the current supercapacitor value ends.

[0098] S14 involves selecting different supercapacitor values ​​and repeating S1-S13 to determine the changes in the cost per kilowatt-hour of energy storage and the initial investment cost of the hybrid energy storage system. This allows for the allocation of the hybrid energy storage system capacity based on real-time wind farm power generation data.

[0099] Example 2

[0100] like Figure 2 As shown, this embodiment provides a capacity selection system for a hybrid energy storage system combining supercapacitors and lithium batteries, comprising:

[0101] The data acquisition and initialization module 101 is used to acquire real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of the supercapacitor and the lithium battery to a first threshold; setting the power reference value for the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle.

[0102] In a preferred embodiment, the first threshold is 50%, thereby ensuring that the supercapacitor and lithium battery are chargeable and dischargeable, and can be flexibly configured according to grid requirements. SOC stands for state of charge, representing the battery's state of charge, which is the available state of the remaining charge in the battery. It is generally expressed as a percentage, typically the ratio of the remaining charge in the battery to its nominal (rated) charge capacity. In this embodiment, the second threshold is 0.8 MW.

[0103] The cycle power reference value determination module 102 is used to take the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for the current cycle.

[0104] The first settlement module 103 is used to settle the SOC of the supercapacitor and lithium battery against the power reference value of the current cycle.

[0105] The second settlement module 104 is used to calculate MPFR. 10 To stabilize demand and settle accounts based on the power baseline for this cycle;

[0106] In a preferred embodiment, the calculation of MPFR 10 Stabilizing demand includes:

[0107] (1) Calculate the allowable range every ten minutes based on the MPFR tolerance per minute;

[0108] (2) Set up an array T with a maximum capacity of ten. d The baseline value for the first cycle of every ten cycles is input into array T before the start of the cycle. d In, T is defined d The maximum value in is a max The minimum value is a min ;

[0109] (3) Calculate the current benchmark value and a max and a min The relationship, if greater than a max Then calculate whether the difference between the current benchmark value and the minimum value exceeds the tolerance. If it does, the excess value is injected into the energy storage system, and the tolerance is used as the new 'a'. max If the tolerance limit is not exceeded, then this value will be used directly as a. max Less than a min The case is greater than a max The situation is similar;

[0110] (4) The baseline value after the above processing is used as the true baseline value for this period and is placed into T in sequence. d This makes subsequent calculations easier.

[0111] (5) The above operation is not performed on the reference value of the first period, but it is directly put into T. d In the middle, the baseline value of each subsequent cycle needs to be processed in the same way, until the tenth cycle is completed, at which point a new cycle will begin.

[0112] It should be noted that this part of the procedure needs to be placed after the SOC's calculation procedure for the benchmark value.

[0113] The energy storage demand calculation module 105 is used to calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection, including: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand for each second.

[0114] The judgment module 106 is used to determine whether the hybrid energy storage system is in the charging range or the discharging range by judging the positive or negative value of the difference d;

[0115] In this embodiment, when the device is in the charging range, the power grid charges the energy storage device, as analyzed below:

[0116] (1) The amount of electricity that needs to be released by the grid is multiplied by the first coefficient (in this embodiment, the first coefficient is set to 0.95) as the amount of electricity to be charged into the supercapacitor. That is, when charging from the grid to the energy storage device, a certain amount of energy (in this embodiment, 5%) needs to be lost, and only 95% of the energy is charged into the energy storage device.

[0117] (2) During charging, the supercapacitor is charged first, and then the lithium battery is charged. During each charging, a simulation calculation is performed on the supercapacitor data. If the SOC of the supercapacitor is still less than the maximum value requirement after charging the required amount of electricity, the charging is completed directly. If the SOC of the supercapacitor exceeds the maximum value requirement after charging the required amount of electricity, the SOC of the supercapacitor is set to the maximum value, and the remaining uncharged electricity is charged into the lithium battery. If the lithium battery is also at its maximum value at this time, the SOC of the lithium battery is set to the maximum value, and the excess electricity is returned to the grid as the electricity that cannot be consumed, thus completing the main part of the charging.

[0118] When in the discharge range, energy is released from the energy storage device back into the grid, as analyzed below:

[0119] (1) Multiply the amount of electricity in the supercapacitor by the second coefficient (in this embodiment, the second coefficient is set to 0.95) as the amount of electricity released from the energy storage device to the grid. That is, when the energy storage device releases electricity to the grid, a certain amount of energy (in this embodiment, 5%) needs to be lost. Only 95% of the energy is released from the energy storage device to the grid. There is also a 5% energy loss. Only 95% can be successfully charged into the grid.

[0120] (2) Start the supercapacitor to discharge first. If the discharge is still insufficient to meet the power required by the grid, the lithium battery will be discharged. The power in the lithium battery will be multiplied by the third coefficient (in this embodiment, the third coefficient is set to 0.95) as the power released by the energy storage device to the grid. That is, when the power is released from the energy storage device to the grid, a certain amount of energy (in this embodiment, 5%) needs to be lost. Only 95% of the energy is released from the energy storage device to the grid. There is also a 5% energy loss. Only 95% can be successfully charged into the grid.

[0121] The third settlement module 107 is used to perform SOC settlement for the supercapacitors and lithium batteries in the previous cycle, including:

[0122] The supercapacitor SOC settlement submodule 1071 is used to settle the SOC of the supercapacitor, including: at the end of each cycle, calculating the difference between the supercapacitor SOC and 50%; if the difference is positive, then in the next cycle, an additional fixed amount of electricity is released to the grid every second; if the electricity is insufficient, it is supplemented by the lithium battery; if both are insufficient, it is the portion that cannot be absorbed; if the difference is negative, then in the next cycle, a fixed amount of electricity is absorbed from the grid every second, and the same applies when it is fully charged.

[0123] The lithium battery SOC settlement submodule 1072 is used to settle the SOC of the lithium battery, including: the calculation of the total settlement value is performed every ten cycles after the supercapacitor calculation, and the settlement rules and program are located in the same place as the supercapacitor.

[0124] The fourth settlement module 108 is used to perform MPFR for the current period. 10 The settlement of the stabilization effect, the MPFR of the current period 10 The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both of which maintain a fixed numerical compensation for each cycle.

[0125] The time point setting and judgment module 109 is used to increment the current time point by 1, let t = t + 1, and judge whether t reaches 60s. If it reaches 60s, return to step S5; otherwise, continue to step S10.

[0126] The time-based calculation module 110 is used to calculate the charging and discharging power, grid-connected power, and SOC of the supercapacitor and lithium battery at each time after completing the settlement at each time, and to calculate whether there is any load loss or wind curtailment at each time.

[0127] The cycle calculation module 111 starts calculating the supercapacitor SOC demand settlement value for the next cycle after a complete 60s cycle ends. Every ten complete cycles, it calculates the lithium battery SOC demand settlement value for the next ten cycles.

[0128] The next cycle reference value determination module 112 is used to calculate the average wind power output of the current cycle and use it as the reference value for the next cycle.

[0129] The cycle time setting and judgment module 113 is used to increment the current cycle time T by 1, let T = T + 1, and judge whether T has reached T. max If the value is not reached, return to step S2; if the value is reached, it means that the data at each moment has been calculated once, and the program for calculating the current supercapacitor value ends.

[0130] The supercapacitor value selection module 114 is used to select different supercapacitor values ​​and repeatedly run S1-S13 to determine the changes in the cost per kilowatt-hour of energy storage and the initial investment cost of the hybrid energy storage system, thereby enabling the allocation of the hybrid energy storage system capacity based on the real-time power generation data of the wind farm.

[0131] This system can implement the method provided in Embodiment 1 above. For details of the method, please refer to the description in Embodiment 1, which will not be repeated here.

[0132] The present invention also provides a memory that stores multiple instructions for implementing the method as described in Embodiment 1.

[0133] like Figure 3 As shown, the present invention also provides an electronic device, including a processor 301 and a memory 302 connected to the processor 301. The memory 302 stores a plurality of instructions, which can be loaded and executed by the processor to enable the processor to perform the method as described in Embodiment 1.

[0134] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries, characterized in that, include: S1, obtain real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of the supercapacitor and the lithium battery to a first threshold; setting the power reference value for the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle. S2, use the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for this cycle; S3 calculates the SOC of the supercapacitor and lithium battery against the power reference value for this cycle. S4, Calculate MPFR 10 To stabilize demand and settle accounts based on the power baseline for this cycle; S5, calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection, including: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand per second. S6, determine whether the hybrid energy storage system is in the charging or discharging range by judging the positive or negative value of the difference d; S7, to settle the supercapacitor and lithium battery SOC of the previous cycle; S8, perform MPFR for the current cycle. 10 The settlement of the stabilization effect, the MPFR of the current period 10 The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both of which maintain a fixed value compensation for each cycle. S9, increment the current time by 1, let t = t + 1, and determine whether t has reached 60s. If it has reached 60s, return to step S5; otherwise, continue to step S10. S10, after completing the settlement at each time point, calculate the charging and discharging power, grid-connected power, and SOC of the supercapacitor and lithium battery at each time point, and calculate whether there is any load shedding or wind curtailment at each time point. S11, after a complete 60s cycle, the calculation of the supercapacitor SOC demand settlement value for the next cycle begins, and every ten complete cycles, the calculation of the lithium battery SOC demand settlement value for the next ten cycles is performed once. S12, calculate the average wind power output for this cycle and use it as the benchmark value for the next cycle; S13, increment the current period time T by 1, let T = T + 1, and determine whether T has reached T1. max If the value is not reached, return to step S2. If the value is reached, it means that the data at each time point has been calculated once, and the program for calculating the current supercapacitor value ends. S14: Select different supercapacitor values ​​and repeat S1-S13 to determine the changes in the cost per kilowatt-hour of energy storage and the initial investment cost of the hybrid energy storage system.

2. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, The first threshold is 50%.

3. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, The second threshold is 0.8MW.

4. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, The calculation of MPFR in S4 10 Stabilizing demand includes: (1) Calculate the allowable range every ten minutes based on the MPFR tolerance per minute; (2) Set up an array T with a maximum capacity of ten. d The baseline value for the first cycle of every ten cycles is input into array T before the start of the cycle. d In the middle, T is defined d The maximum value in is a max The minimum value is a min ; (3) Calculate the current benchmark value and a max and a min The relationship, if greater than a max Then calculate whether the difference between the current benchmark value and the minimum value exceeds the tolerance. If it does, the excess value is injected into the energy storage system, and the tolerance is used as the new 'a'. max If the tolerance limit is not exceeded, then this value will be used directly as a. max Less than a min The case is greater than a max The situation is the same; (4) The baseline value after the above processing is used as the true baseline value for this period and is placed into T in sequence. d middle; (5) The baseline value for the first period is directly entered into T. d In this process, the baseline value for each subsequent cycle needs to undergo the same operation until the tenth cycle is completed, at which point a new cycle begins.

5. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, In step S6, when the device is in the charging range, the power grid charges the energy storage device, including: (1) The amount of electricity that needs to be released by the grid is multiplied by the first coefficient to obtain the amount of electricity to be charged into the supercapacitor. That is, when charging from the grid to the energy storage device, a certain amount of energy needs to be lost; the first coefficient is 0.

95. (2) During charging, the supercapacitor is charged first, and then the lithium battery is charged. During each charging, a simulation calculation is performed on the supercapacitor data. If the SOC of the supercapacitor is still less than the maximum value requirement after charging the required amount of electricity, the charging is completed directly. If the SOC of the supercapacitor exceeds the maximum value requirement after charging the required amount of electricity, the SOC of the supercapacitor is set to the maximum value, and the remaining uncharged electricity is charged into the lithium battery. If the lithium battery is also at its maximum value at this time, the SOC of the lithium battery is set to the maximum value, and the excess electricity is returned to the grid as the electricity that cannot be consumed, thus completing the main part of the charging.

6. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, In step S6, when in the discharge range, releasing energy from the energy storage device to the power grid includes: (1) Multiply the amount of electricity in the supercapacitor by the second coefficient to obtain the amount of electricity released from the energy storage device to the grid. That is, when releasing electricity from the energy storage device to the grid, a certain amount of energy needs to be lost; the second coefficient is 0.

95. (2) Start the supercapacitor to discharge first. If the discharge is still insufficient to meet the power required by the grid, the lithium battery will be discharged. The power in the lithium battery will be multiplied by the third coefficient to obtain the power released by the energy storage device to the grid. That is, when the power is released from the energy storage device to the grid, a certain amount of energy needs to be lost. The third coefficient is 0.

95.

7. The method for selecting the capacity of a hybrid energy storage system combining supercapacitors and lithium batteries according to claim 1, characterized in that, S7 includes: S71 calculates the SOC of the supercapacitor, including: at the end of each cycle, calculating the difference between the supercapacitor's SOC and 50%. If the difference is positive, a fixed amount of electricity is discharged to the grid every second in the next cycle. If the electricity is insufficient, it is supplemented by the lithium battery. If both are insufficient, it is the portion that cannot be absorbed. If the difference is negative, a fixed amount of electricity is absorbed from the grid every second in the next cycle. The same applies when it is fully charged. S72 calculates the SOC of the lithium battery, including: the total settlement value is calculated after the supercapacitor calculation, and the settlement is performed every ten cycles. The settlement rules and procedures are located in the same place as the supercapacitor.

8. A capacity selection system for a hybrid energy storage system combining supercapacitors and lithium batteries, used to implement the method described in any one of claims 1-7, characterized in that, include: The data acquisition and initialization module (101) is used to acquire real-time power generation data of the power station and perform data initialization. The data initialization includes: setting the SOC of the supercapacitor and the lithium battery to a first threshold; setting the power reference value of the first capacity selection to a second threshold; setting the cycle time parameter T to 0; and setting the single time parameter t to 0 at the beginning of each sub-cycle. The cycle power reference value determination module (102) is used to take the average power of the supercapacitor and lithium battery in the previous cycle as the power reference value for the current cycle. The first settlement module (103) is used to settle the SOC of the supercapacitor and lithium battery against the power reference value of the current cycle. The second settlement module (104) is used to calculate MPFR. 10 To stabilize demand and settle accounts based on the power baseline for this cycle; The energy storage demand calculation module (105) is used to calculate the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection, including: creating a small loop in each cycle with a step size of 1 second, and using the difference d between the actual wind turbine output value and the power reference value selected in the first capacity selection as the energy storage demand for each second. The judgment module (106) is used to determine whether the hybrid energy storage system is in the charging range or the discharging range by judging the positive or negative value of the difference d; The third settlement module (107) is used to settle the supercapacitor and lithium battery SOC of the previous cycle. The fourth settlement module (108) is used to perform MPFR for the current period. 10 The settlement of the stabilization effect, the MPFR of the current period 10 The method for calculating the stabilization effect is similar to that for the supercapacitor and lithium battery SOC calculation in the previous cycle, both of which maintain a fixed value compensation for each cycle. The time point setting and judgment module (109) is used to increment the current time point by 1, let t = t + 1, and judge whether t reaches 60s. If it reaches 60s, return to step S5; otherwise, continue to step S10. The time calculation module (110) is used to calculate the charging and discharging power, grid connection power, and SOC of the supercapacitor and lithium battery at each time after the settlement at each time, and to calculate whether there is a loss of load and wind curtailment at each time. The cycle calculation module (111) starts calculating the supercapacitor SOC demand settlement value for the next cycle after a complete 60s cycle ends. Every ten complete cycles, the lithium battery SOC demand settlement value for the next ten cycles is calculated once. The next cycle reference value determination module (112) is used to calculate the average wind power output of the current cycle and use it as the reference value for the next cycle. The cycle time setting and judgment module (113) is used to increment the current cycle time T by 1, let T = T + 1, and judge whether T has reached T. max If the value is not reached, return to step S2. If the value is reached, it means that the data at each time point has been calculated once, and the program for calculating the current supercapacitor value ends. The supercapacitor value selection module (114) is used to select different supercapacitor values ​​and repeatedly run S1-S13 to determine the cost per kilowatt-hour of energy storage and the change in the initial investment cost of the hybrid energy storage system.

9. An electronic device, characterized in that, It includes a processor and a memory, the memory storing multiple instructions, and the processor being used to read the instructions and execute the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a plurality of instructions, which can be read by a processor and executed as described in any one of claims 1-7.

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