Hybrid energy storage system power distribution method and parameter configuration method based on wavelet transform

Abstract

The invention relates to the technical field of power distribution of a power system, and discloses a wavelet transform-based power distribution method of a hybrid energy storage system, the hybrid energy storage system comprises energy type energy storage and power type energy storage, and the method is characterized by comprising the following steps: S1, obtaining a power control instruction Pe (k) of the hybrid energy storage system, decomposing the power control instruction Pe (k) into a high-frequency power component and a low-frequency power component by using a fast Mallat algorithm of discrete wavelet transform; and S2, the low-frequency power component is responded by using energy-type energy storage, and the high-frequency power component is responded by using power-type energy storage. The hybrid energy storage system power distribution method is high in power distribution efficiency. The invention further discloses a hybrid energy storage system parameter configuration method based on wavelet transformation.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution of electric power systems, and in particular to a power distribution method and a parameter configuration method of a hybrid energy storage system based on wavelet transform. Background Art

[0002] Under the dual pressure of the growth of national electricity demand and the energy crisis, the development of traditional electricity can no longer meet the growth rate of electricity demand. Based on this, renewable energy such as wind power and solar energy will gradually replace fossil energy and continuously increase its proportion in energy consumption. In recent years, renewable energy is rapidly penetrating into all aspects of the world's energy system and has become the main direction of resource transformation.

[0003] However, the access of large-scale distributed power sources (wind power, solar power, etc.) to the power grid will lead to increased line losses, reduced power quality, and limited transmission and distribution capabilities of the power grid. Energy storage systems are devices that can convert electricity into other forms of energy for storage so that they can be released as electrical energy when needed. They balance supply and demand, improve power quality, and increase the flexibility of the power system. Therefore, energy storage systems play a vital role in renewable energy power generation systems.

[0004] Energy storage technology has been widely studied and has achieved a lot of technical results. According to the energy storage characteristics, common energy storage devices can be roughly divided into two categories: energy type and power type. Although energy type energy storage devices have high energy density, they have slow response speed and short cycle life. The power fluctuation of distributed power sources will have a greater impact on their service life. In contrast, power type energy storage devices have advantages such as high power density and fast response speed. If the two are combined to form a hybrid energy storage system, their respective characteristics can be brought into play, effectively smoothing the power fluctuation of the system while extending the service life of the energy storage device. In short, the hybrid energy storage system (HESS) realizes the complementary advantages of energy type energy storage devices and power type energy storage devices.

[0005] The improvement of the comprehensive performance of the hybrid energy storage system depends to a greater extent on the coordination and cooperation between the energy storage devices in the energy storage system. Therefore, how to improve the power distribution efficiency of the hybrid energy storage system, improve the coordinated control between the energy storage devices in the hybrid energy storage system, and optimize the capacity configuration of the energy storage devices are the key points of our research. These research focuses are of great significance in improving the response speed and work efficiency of the hybrid energy storage system, improving the utilization rate of renewable energy, reducing power fluctuations in the power grid system, and ensuring the safe and stable operation of the power grid system. Summary of the invention

[0006] In order to solve the technical problems of how to improve the power distribution efficiency of hybrid energy storage systems, improve the coordinated control between energy storage devices in hybrid energy storage systems, and optimize the capacity configuration of energy storage devices, the present invention provides a hybrid energy storage system power distribution method and parameter configuration method based on wavelet transform, which can be used to control the power control instruction P of the hybrid energy storage system. e (k) The power distribution efficiency is improved by using energy storage to respond to low-frequency power components and power storage to respond to high-frequency power components; the energy storage and power storage are coordinated and controlled, and the power control instructions P for M typical days are adopted. e (k) The final rated power and final rated capacity of the hybrid energy storage system calculated in a specific way are highly typical.

[0007] The present invention provides a hybrid energy storage system power allocation method based on wavelet transform, wherein the hybrid energy storage system includes energy type energy storage and power type energy storage, and comprises the following steps:

[0008] S1. Obtain the power control instruction P of the hybrid energy storage system e (k) The power control instruction P is converted into e (k) decomposition into high-frequency power components and low-frequency power components;

[0009] S2. Use energy-type energy storage to respond to low-frequency power components, and use power-type energy storage to respond to high-frequency power components.

[0010] Furthermore, in S1, the power control instruction P is converted into e (k) The decomposed expression is:

[0011] Where P e (k) represents the power control command of the hybrid energy storage system obtained at time k; n represents the number of decompositions of the discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i Represents the high-frequency power component decomposed i times.

[0012] Furthermore, the energy type energy storage includes a battery, and the power type energy storage includes a supercapacitor; correspondingly, in S2, the power expressions of the battery and the supercapacitor are:

[0013] In the formula, k represents a certain moment; n represents the number of decompositions of discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i represents the high-frequency power component decomposed i times; P b(k) represents the battery charging and discharging power; P sc (k) represents the supercapacitor charging and discharging power.

[0014] Furthermore, in S2, it is assumed that the lowest frequency signal that the supercapacitor can respond to is f sc.min , then the minimum value of the high-frequency power signal assigned to the supercapacitor cannot be less than the value of the supercapacitor's lowest frequency signal, that is,

[0015] Furthermore, the hybrid energy storage system power allocation method further includes: S3, according to the frequency setting requirements of the response power required by the energy type energy storage and the power type energy storage, while considering the rationality of the parameter configuration of the hybrid energy storage system, determining the number of decompositions n of the fast Mallat algorithm of the discrete wavelet transform that meets the requirements, and then performing the power control instruction P e Decomposition of (k).

[0016] Compared with the prior art, the present invention has the following technical effects: the power distribution method of the hybrid energy storage system of the present invention uses this power distribution method to control the power control instruction P of the hybrid energy storage system e (k) distribution, using energy-type energy storage to respond to low-frequency power components, and using power-type energy storage to respond to high-frequency power components, can give full play to the characteristics of different types of energy storage devices (i.e., energy-type energy storage and power-type energy storage), and the power distribution efficiency is improved.

[0017] The present invention also provides a hybrid energy storage system parameter configuration method based on wavelet transform, comprising the following steps:

[0018] S1. Based on any of the above-mentioned hybrid energy storage system power allocation methods, obtain the power sequence of energy storage and power storage in the hybrid energy storage system on M typical days;

[0019] S2. Determine the rated power and rated capacity of the hybrid energy storage system in M ​​typical days based on the above power sequence;

[0020] S3. Based on the rated power and rated capacity of M typical days, the final rated power and final rated capacity of the hybrid energy storage system are calculated by weighted average.

[0021] Furthermore, the energy type energy storage includes a battery, and the power type energy storage includes a supercapacitor. In S2, the power expression of the rated power of the battery and the supercapacitor is:

[0022]

[0023] Where P b Represents the rated power of the battery; P b (k) represents the battery charging and discharging power; ub Represents the reliability factor of the battery rated power; P sc Represents the rated power of the supercapacitor, P sc (k) represents the supercapacitor charging and discharging power; μ sc Represents the rated power reliability factor of the supercapacitor; where u b and μ sc Both are greater than 1.

[0024] Furthermore, the energy type energy storage includes a battery, and the power type energy storage includes a super capacitor. In S2, the expressions of the rated capacities of the battery and the super capacitor are:

[0025]

[0026] In the formula, E b Represents the rated capacity of the battery, E b (K) represents the remaining capacity of the battery at time k, λ b Represents the rated capacity reliability factor of the battery; E sc Represents the rated capacity of the supercapacitor, E sc (K) represents the remaining capacity of the supercapacitor at time k, λ sc Represents the rated capacity reliability factor of the supercapacitor; where λ b and λ sc Both are greater than 1.

[0027] Furthermore, the calculation formula for the final rated power and final rated capacity of the energy storage system is:

[0028]

[0029] Where P rank.M and E rank.M It indicates that the rated power and rated capacity of M typical days are sorted by numerical value. The smaller M is, the larger the rated power or rated capacity of the typical day is, and vice versa. f represents the weight coefficient, where f1+f2+f3+f4+…+f M =1, the smaller M is, the greater the weight coefficient of the typical day is, and vice versa.

[0030] Compared with the prior art, the present invention has the following technical effects: the hybrid energy storage system parameter configuration method of the present invention coordinates the control of energy type energy storage and power type energy storage, adopts the power control instruction P of multiple typical days e (k) The final rated power and final rated capacity of the hybrid energy storage system calculated in a specific way are highly typical and have certain guiding significance for the parameter configuration of the hybrid energy storage system in practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 1 is a flow chart of a hybrid energy storage system power allocation method based on wavelet transform according to the first embodiment of the present invention;

[0032] Figure 2 is a schematic diagram of the decomposition number and the frequency of each component according to the first embodiment of the present invention;

[0033] Figure 3 Schematic diagram of the frequency range of the battery and the supercapacitor suitable for responding to the frequency according to the first embodiment of the present invention;

[0034] Figure 4 is a flow chart of a hybrid energy storage system parameter configuration method based on wavelet transform according to the second embodiment of the present invention;

[0035] Figure 5 is a data simulation diagram of the power control instruction Pe(k) of a typical day 2 in the second embodiment of the present invention;

[0036] Figure 6 is a data simulation diagram of the change of the low-frequency power component with the decomposition times according to the second embodiment of the present invention;

[0037] Figure 7 It is a data simulation diagram of the battery power and the supercapacitor power of the second embodiment of the present invention. DETAILED DESCRIPTION

[0038] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0039] Embodiment 1, as Figures 1 to 3 As shown, a hybrid energy storage system power allocation method based on wavelet transform includes the following steps:

[0040] S1. Obtain the power control instruction P of the hybrid energy storage system e (k) The power control instruction P is converted into e (k) decomposition into high-frequency power components and low-frequency power components;

[0041] S2. Use energy-type energy storage to respond to low-frequency power components, and use power-type energy storage to respond to high-frequency power components. Since there are differences in response speed, energy density and power density between power-type energy storage and energy-type energy storage, power allocation needs to be carried out according to the frequency of the signal to be responded to.

[0042] The hybrid energy storage system power allocation method of this embodiment uses this power allocation method to control the power control instruction P of the hybrid energy storage system. e(k) distribution, using energy-type energy storage to respond to low-frequency power components, and using power-type energy storage to respond to high-frequency power components, can give full play to the characteristics of different types of energy storage devices (i.e., energy-type energy storage and power-type energy storage), and the power distribution efficiency is improved.

[0043] Based on the above embodiment, in S1, the power control instruction P is converted into e (k) The decomposed expression is:

[0044] Where P e (k) represents the power control command of the hybrid energy storage system obtained at time k; n represents the number of decompositions of the discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i Represents the high-frequency power component decomposed i times.

[0045] On the basis of the above embodiments, the energy type energy storage includes a battery, and the power type energy storage includes a super capacitor; correspondingly, in S2, the power expressions of the battery and the super capacitor are: (2)

[0046] In the formula, k represents a certain moment; n represents the number of decompositions of discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i represents the high-frequency power component decomposed i times; P b (k) represents the battery charging and discharging power; P sc (k) represents the supercapacitor charging and discharging power.

[0047] Using the fast Mallat algorithm of discrete wavelet transform to calculate P e (k) Perform n decompositions. The relationship between the number of decompositions and the frequency of each component is as follows: Figure 2 According to the sampling theorem, if the original signal is sampled and the frequency of the sampled signal does not drop by more than one time, the original signal information will not be lost. When performing the fast Mallat algorithm of discrete wavelet transform, the length of the input signal and the output signal are kept consistent. Assuming that the original signal frequency is f s , after sampling, the signal frequency is f s / 2, after n times of decomposition, the frequency range of the low-frequency power signal is The frequency range of the 1st to nth high-frequency power signal is

[0048] According to the main performance parameters of energy-type energy storage and power-type energy storage, power-type energy storage has the characteristics of fast response speed, short charging and discharging time, and long cycle life, and is suitable for responding to high-frequency power signals; energy-type energy storage has a slow response speed, and its cycle life is lower than that of power-type energy storage, but it can be charged and discharged for a long time, and is suitable for responding to low-frequency power signals.

[0049] Therefore, in this embodiment, according to the characteristics of power-type energy storage and energy-type energy storage, energy-type energy storage (ie, battery) is used to respond to low-frequency power components, and power-type energy storage (ie, supercapacitor) is used to respond to high-frequency power components.

[0050] like Figure 3 As shown, the supercapacitor in this embodiment is suitable for responding to power signals in the millisecond to minute range, and the storage battery is suitable for responding to power signals in the second to hour range. Figure 3 It can be seen that the battery can respond to power signals at the hour level at the minimum, so the battery can respond to power signals with a frequency greater than the hour level, but using the battery to respond to signals with too high a frequency will increase the number and frequency of battery charge and discharge conversions, seriously affecting its service life. Supercapacitors can respond to power signals at the minute level at the minimum, and cannot respond to power signals with a lower frequency.

[0051] Based on the above embodiments, in S2, it is assumed that the lowest frequency signal that the supercapacitor can respond to is f sc.min , then the minimum value of the high-frequency power signal assigned to the supercapacitor cannot be less than the value of the supercapacitor's lowest frequency signal, that is,

[0052] According to the above conclusions, in this embodiment, a battery is used to bear power signals with a frequency below the minute level, and a supercapacitor is used to bear power signals with a frequency above the minute level.

[0053] On the basis of the above embodiments, the power allocation method of the hybrid energy storage system further includes: S3, according to the frequency setting requirements of the response power required by the energy type energy storage and the power type energy storage, while considering the rationality of the parameter configuration of the hybrid energy storage system, determining the number of decompositions n of the fast Mallat algorithm of the discrete wavelet transform that meets the requirements, and then performing the power control instruction P e The decomposition times are set to a fixed value, and this power allocation method is used to control the power control instruction P of the hybrid energy storage system. e (k) is used for distribution, energy-type energy storage is used to respond to low-frequency power components, and power-type energy storage is used to respond to high-frequency power components, so that the power distribution efficiency is improved.

[0054] Embodiment 2, as Figures 4 to 7 As shown, a hybrid energy storage system parameter configuration method based on wavelet transform includes the following steps:

[0055] S1. Based on any of the above-mentioned hybrid energy storage system power allocation methods, obtain the power sequence of energy storage and power storage in the hybrid energy storage system on M typical days;

[0056] S2. Determine the rated power and rated capacity of the hybrid energy storage system in M ​​typical days based on the above power sequence;

[0057] S3. Based on the rated power and rated capacity of M typical days, the final rated power and final rated capacity of the hybrid energy storage system are calculated by weighted average.

[0058] The hybrid energy storage system parameter configuration method of this embodiment coordinates the control of energy type energy storage and power type energy storage, and adopts the power control instructions P of multiple typical days. e (k) The final rated power and final rated capacity of the hybrid energy storage system calculated in a specific way are highly typical and have certain guiding significance for the parameter configuration of the hybrid energy storage system in practical applications.

[0059] On the basis of the above embodiment, the energy type energy storage includes a battery, and the power type energy storage includes a super capacitor. In S2, the power expression of the rated power of the battery and the super capacitor is:

[0060]

[0061] Where P b Represents the rated power of the battery; P b (k) represents the battery charging and discharging power; u b Represents the reliability factor of the battery rated power; P sc Represents the rated power of the supercapacitor, P sc (k) represents the supercapacitor charging and discharging power; μ sc Represents the rated power reliability factor of the supercapacitor.

[0062] On the basis of the above embodiment, the energy type energy storage includes a battery, and the power type energy storage includes a super capacitor. In S2, the expressions of the rated capacities of the battery and the super capacitor are:

[0063]

[0064] In the formula, E b Represents the rated capacity of the battery, E b (K) represents the remaining capacity of the battery at time k, λ b Represents the rated capacity reliability factor of the battery; E sc Represents the rated capacity of the supercapacitor, E sc (K) represents the remaining capacity of the supercapacitor at time k, λ scRepresents the rated capacity reliability factor of the supercapacitor; where u b , μ sc , b and λ sc are greater than 1, but u b , μ sc , b and λ sc The specific value of the average can be flexibly configured according to the specific situation.

[0065] Specifically, the method of obtaining formula (4) and formula (5) is as follows:

[0066] The power expression for the rated power of batteries and supercapacitors is:

[0067]

[0068] In the formula, E represents the energy storage capacity of energy storage or power storage; T represents the operation time of energy storage or power storage; P(t) represents the energy storage power sequence of energy storage or power storage.

[0069]

[0070] In the formula, E b (0) and E sc (0) represents the initial capacity of the battery and supercapacitor respectively; E b (K) and E sc (K) represents the remaining energy capacity of the battery and supercapacitor at time k; P b (i) represents the low-frequency power component of the battery after decomposition i times; P sc (i) represents the high-frequency power component of the supercapacitor decomposed i times; Δt represents the operation time of the battery or supercapacitor.

[0071] The rated capacity of the battery and supercapacitor is E b and E sc The power expression of the maximum capacity required during the operation time can be expressed as:

[0072]

[0073] In the formula, max{E b (K)} and max{E sc (K)} represent the maximum value of the remaining capacity of the battery and supercapacitor at time k, min{E b (K)} and min{E sc (K)} represent the minimum value of the remaining capacity of the battery and the supercapacitor at time k respectively.

[0074] In order to prevent the lack of universality and guidance of the rated power and rated capacity of the hybrid energy storage system due to too little sample data analyzed, and to prevent extreme situations and uncertainties in the operation of the hybrid energy storage system, a reliability coefficient can be multiplied in formula (7) and formula (10) to obtain formula (4) and formula (5).

[0075] Based on the above embodiments, the calculation formula for the final rated power and the final rated capacity of the energy storage system is:

[0076]

[0077] Where P rank.M and E rank.M It indicates that the rated power and rated capacity of M typical days are sorted by numerical value. The smaller M is, the larger the rated power or rated capacity of the typical day is, and vice versa. f represents the weight coefficient, where f1+f2+f3+f4+…+f M =1, the smaller M is, the greater the weight coefficient of the typical day is, and vice versa.

[0078] Next, four days are randomly selected from the measured wind power data of a wind farm in Hubei Province in 2021 as typical days, that is, M=4, which are typical day 1, typical day 2, typical day 3 and typical day 4. The power control instructions P e (k) As the research object, four groups of power control instructions P e (k) Simulation is performed, and the simulation results of typical day 2 are used as an example to demonstrate and analyze the power control instruction P of typical day 2. e (k) Figure 5 shown.

[0079] In the power control command P e (k) Before decomposition, we first need to determine the decomposition times n of the hybrid energy storage system. From the power allocation method of the hybrid energy storage system, we know that the fast Mallat algorithm of discrete wavelet transform needs to decompose the low-frequency power component with minute level as the boundary and the high-frequency power component of each level. The control period of the energy storage system is set to 15s, that is, the control frequency is 1 / 15. According to the above formula (3), we can derive

[0080] According to the above formula (11), the power control instruction P e (k) After 1 to 4 decompositions, the low-frequency power component and high-frequency power component that meet the requirements can be obtained, and the power control instruction P e (k) The low-frequency power components obtained by decomposing 1 to 4 times are as follows Figure 6 As shown, Figure 6The total energy storage power in is the energy storage power of the hybrid energy storage system. Figure 6 It can be seen that as the number of decompositions increases, the fluctuation amplitude of the low-frequency power component of the energy storage power of the hybrid energy storage system is smaller and smaller than that of the original energy storage power. At the same time, as the frequency of the energy storage component gradually decreases, the change trend of the low-frequency power component of the energy storage becomes smoother, that is, the number of charge and discharge conversions of the low-frequency power component gradually decreases with the increase of the number of decompositions. According to the hybrid energy storage system parameter configuration method of the hybrid energy storage system, the specific relationship between the number of decompositions of the discrete wavelet transform and the parameters of the hybrid energy storage system is shown in Table 1 below.

[0081] Table 1 Relationship between discrete wavelet transform decomposition times and hybrid energy storage system parameters

[0082]

[0083] From the data in Table 1, it can be seen that as the number of decompositions increases, the required rated power and charge-discharge conversion times of the battery decrease rapidly, and the required rated capacity also decreases gradually; the required rated power and rated capacity of the supercapacitor gradually increase, and the charge-discharge conversion times decrease slowly as the number of decompositions increases. In terms of the number of charge-discharge conversions, the more decompositions there are, the more beneficial it is to extend the service life of the hybrid energy storage system. However, the unit capacity cost of the supercapacitor is much greater than that of the battery. Considering the investment cost of the hybrid energy storage system, it is decided to set the power control instruction P e (k) is decomposed twice. Since the Daubechies series wavelet function has good suppression ability in denoising, filtering and data compression, after a lot of simulation analysis, the db4 wavelet is finally selected to deal with the power control instruction P of the typical day 2. e (k) is decomposed. The battery power and supercapacitor power obtained according to formula (2) are as follows: Figure 7 shown.

[0084] Then, according to formula (4) and formula (5), the power control command P of four typical days is calculated. e (k) The rated power and rated capacity of the hybrid energy storage system obtained are shown in Table 2 below.

[0085] Table 2 Configuration parameters of the rated power and rated capacity of the hybrid energy storage system on each typical day

[0086]

[0087]

[0088] According to formula (6), we can derive

[0089] In the formula, f1+f2+f3+f4=1, f1, f2, f3, f4 are 0.6, 0.25, 0.1, 0.05 respectively.

[0090] The configuration parameters of the final rated power and final rated capacity of the hybrid energy storage system calculated according to formula (12) are shown in Table 3 below.

[0091] Table 3 Configuration parameters of the final rated power and final rated capacity of the hybrid energy storage system

[0092] Energy storage equipment Rated power / MW Rated capacity / kW·h Supercapacitor 2.959 21.211 Battery 1.765 49.657

[0093] The embodiments described above are only preferred embodiments of the present invention and are only used to explain the present invention, not to limit the scope of implementation of the present invention. For those skilled in the art, other implementation methods can certainly be easily made by replacement or modification based on the technical contents disclosed in this specification. Therefore, all changes and improvements made to the principles and process conditions of the present invention should be included in the scope of the patent application of the present invention.

Claims

1. A power allocation method for a hybrid energy storage system based on wavelet transform, wherein the hybrid energy storage system includes energy type energy storage and power type energy storage, characterized in that: The following steps are involved: S1. Obtain the power control instruction P of the hybrid energy storage system e (k) The power control instruction P is converted into e (k) decomposition into high-frequency power components and low-frequency power components; S2. Use energy-type energy storage to respond to low-frequency power components, and use power-type energy storage to respond to high-frequency power components.

2. The hybrid energy storage system power distribution method according to claim 1, characterized in that: In S1, the power control instruction P is converted into e (k) The decomposed expression is: Where P e (k) represents the power control command of the hybrid energy storage system obtained at time k; n represents the number of decompositions of the discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i Represents the high-frequency power component decomposed i times.

3. The hybrid energy storage system power distribution method according to claim 1, characterized in that: Energy-type energy storage includes batteries, and power-type energy storage includes supercapacitors; correspondingly, in S2, the power expressions of batteries and supercapacitors are: In the formula, k represents a certain moment; n represents the number of decompositions of discrete wavelet transform; A n represents the low-frequency power component decomposed n times; D i represents the high-frequency power component decomposed i times; P b (k) represents the battery charging and discharging power; P sc (k) represents the supercapacitor charging and discharging power.

4. The hybrid energy storage system power distribution method according to claim 3, characterized in that: In S2, it is assumed that the lowest frequency signal that the supercapacitor can respond to is f sc.min , then the minimum value of the high-frequency power signal assigned to the supercapacitor cannot be less than the value of the supercapacitor's lowest frequency signal, that is, (3).

5. The hybrid energy storage system power distribution method according to claim 1, characterized in that: The hybrid energy storage system power allocation method further includes: S3, according to the frequency setting requirements of the response power required by the energy type energy storage and the power type energy storage, while considering the rationality of the parameter configuration of the hybrid energy storage system, determining the decomposition times n of the fast Mallat algorithm of the discrete wavelet transform that meets the requirements, and then performing the power control instruction P e Decomposition of (k).

6. A hybrid energy storage system parameter configuration method based on wavelet transform, characterized in that: The following steps are involved: S1. Based on the power allocation method of the hybrid energy storage system according to any one of claims 1 to 5, the power sequence of the energy storage and power storage in the hybrid energy storage system on M typical days is obtained; S2. Determine the rated power and rated capacity of the hybrid energy storage system in M ​​typical days based on the above power sequence; S3. Based on the rated power and rated capacity of M typical days, the final rated power and final rated capacity of the hybrid energy storage system are calculated by weighted average.

7. The hybrid energy storage system parameter configuration method according to claim 6, characterized in that: Energy type energy storage includes batteries, power type energy storage includes super capacitors, and in S2, the power expression of the rated power of the battery and super capacitor is: Where P b Represents the rated power of the battery; P b (k) represents the battery charging and discharging power; u b Represents the reliability factor of the battery rated power; P sc Represents the rated power of the supercapacitor, P sc (k) represents the supercapacitor charging and discharging power; μ sc Represents the rated power reliability factor of the supercapacitor; where u b and μ sc Both are greater than 1.

8. The hybrid energy storage system parameter configuration method according to claim 6, characterized in that: Energy type energy storage includes batteries, and power type energy storage includes supercapacitors. In S2, the expressions for the rated capacities of batteries and supercapacitors are: In the formula, E b Represents the rated capacity of the battery, E b (K) represents the remaining capacity of the battery at time k, λ b Represents the rated capacity reliability factor of the battery; E sc Represents the rated capacity of the supercapacitor, E sc (K) represents the remaining capacity of the supercapacitor at time k, λ sc Represents the rated capacity reliability factor of the supercapacitor; where λ b and λ sc Both are greater than 1.

9. The hybrid energy storage system parameter configuration method according to claim 6, characterized in that: The calculation formula for the final rated power and final rated capacity of the energy storage system is: Where P rank.M and E rank.M It indicates that the rated power and rated capacity of M typical days are sorted by numerical value. The smaller M is, the larger the rated power or rated capacity of the typical day is, and vice versa. f represents the weight coefficient, where f1+f2+f3+f4+…+f M =1, the smaller M is, the greater the weight coefficient of the typical day is, and vice versa.

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