An automatic generation control method and system under participation of a composite energy storage resource

Abstract

The application discloses an automatic generation control method and system under participation of composite energy storage resources. tie The application obtains a regional control deviation signal ACE according to the regional exchange power deviation ΔP and the frequency deviation amount Δf, obtains a high-frequency component and a low-frequency component of frequency modulation demand based on the regional control deviation signal ACE, uses a flywheel energy storage of an energy storage system to bear the high-frequency component of the frequency modulation demand, and uses electrochemical energy storage and a traditional frequency modulation unit to bear the low-frequency component of the frequency modulation demand. The application applies the power-type flywheel energy storage and the energy-type electrochemical energy storage to grid frequency modulation, and can complement different types of energy storage capacity and power, and complement economic cost and a service life.

Description

Technical Field

[0001] This invention relates to the field of automatic power generation control technology, specifically to an automatic power generation control method and system with the participation of composite energy storage resources. Background Technology

[0002] In recent years, an increasing number of distributed renewable energy sources (such as wind power and photovoltaics) have been connected to the power grid. Their inherent intermittent and fluctuating characteristics have exacerbated the imbalance between active power output and demand, leading to increased frequency fluctuations in the power grid. On the other hand, the increasingly heavy load and the expansion of the power grid have also increased the frequency regulation burden on the power system. Therefore, higher demands are placed on the frequency regulation capabilities of the power grid. Currently, traditional frequency regulation units are mainly thermal power units. These units have inherent drawbacks such as long response times, slow response speeds, and low ramp rates, resulting in limited frequency control capabilities for short cycles when frequency regulation capacity is limited. Compared to traditional frequency regulation units, energy storage systems offer a series of advantages, including short response times, high ramp rates, precise power regulation, and the ability to operate in four quadrants. They are increasingly participating in all aspects of the power system, including generation, transmission, distribution, and consumption, playing a role in smoothing intermittent energy power fluctuations, peak shaving and valley filling, and participating in voltage and frequency regulation. Compared to electrochemical energy storage, flywheel energy storage currently offers significant advantages in terms of safety, power density, cycle life, and environmental adaptability. Furthermore, flywheel energy storage is not affected by rapid and frequent charging and discharging, thus its technical performance and lifespan are not impacted. However, it requires a large initial investment and is slightly less efficient in terms of energy density. Therefore, combining power-type flywheel energy storage with energy-type electrochemical energy storage for grid frequency regulation can achieve complementarity in both capacity and power of different energy storage types, as well as in economic cost and lifespan. However, how to achieve coordinated dispatch of power-type flywheel energy storage and energy-type electrochemical energy storage remains a key technical problem that urgently needs to be solved. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an automatic power generation control method and system with the participation of composite energy storage resources. The present invention combines power-type flywheel energy storage with energy-type electrochemical energy storage for grid frequency regulation, which can achieve complementarity in the capacity and power of different types of energy storage, as well as complementarity in economic cost and life cycle.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] An automatic power generation control method involving composite energy storage resources includes:

[0006] S101, based on the inter-regional exchange power deviation ΔP tie The area control deviation signal ACE is obtained by measuring the frequency deviation Δf.

[0007] S102 obtains the high-frequency and low-frequency components of frequency regulation demand based on the regional control deviation signal ACE. The flywheel energy storage of the energy storage system is used to handle the high-frequency component of frequency regulation demand, while electrochemical energy storage and traditional frequency regulation units are used to handle the low-frequency component of frequency regulation demand.

[0008] Optionally, the functional expression for obtaining the area control deviation signal ACE in step S101 is:

[0009] A ce =P tie +Δf,

[0010] In the above formula, A ce The region control deviation signal ACE is represented by B, where B represents the frequency deviation coefficient and ΔP represents the inter-regional power exchange deviation. tie The difference between the inter-regional exchange power value and the rated value is given by Δf, and the frequency deviation is the difference between the system frequency value and the rated value.

[0011] Optionally, step S102 includes:

[0012] S201, the discrete Fourier transform of the regional control deviation signal ACE is used to obtain the frequency domain distribution of the frequency modulation requirement, and the boundary point between high and low frequencies in the frequency domain distribution is determined.

[0013] S202 divides the frequency domain distribution into high and low frequencies based on the high-low frequency boundary point, thereby obtaining the high-frequency and low-frequency components of the frequency regulation requirement. The flywheel energy storage of the energy storage system undertakes the high-frequency component of the frequency regulation requirement, while electrochemical energy storage and traditional frequency regulation units undertake the low-frequency component of the frequency regulation requirement.

[0014] Optionally, step S202 includes:

[0015] S301, the area control deviation signal ACE is low-pass filtered by a low-pass filter that uses the high-low frequency boundary as the cutoff frequency to obtain the low-frequency component ACE. low ;

[0016] S302, subtract the low-frequency component ACE from the area control deviation signal ACE. low Obtain high-frequency component ACE high ACE of high frequency components high Limiting is applied to the high-frequency components allocated to flywheel energy storage. ;

[0017] S303 subtracts the high-frequency component allocated to the energy storage system from the area control deviation signal ACE to obtain the low-frequency component allocated to the electrochemical energy storage and the traditional frequency regulation unit. ;

[0018] S304 uses a flywheel energy storage system to handle the high-frequency components of frequency regulation requirements. Electrochemical energy storage and traditional frequency regulation units handle the low-frequency components of frequency regulation requirements. .

[0019] Optionally, obtaining the frequency deviation Δf in step S101 includes: firstly, obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit, wherein the energy storage system includes flywheel energy storage and electrochemical energy storage and the traditional frequency regulation unit; then, obtaining the frequency regulation output of the energy storage system and the traditional unit, and the power exchange deviation ΔP between each region. tie and the continuous load disturbance ΔP of the system L The system power deviation is obtained by summing the results, and then the system power deviation is used to control the synchronous generator to generate electricity, thereby obtaining the frequency deviation Δf.

[0020] Optionally, when separately acquiring the frequency regulation output of the energy storage system and the traditional frequency regulation unit, acquiring the frequency regulation output of the electrochemical energy storage system includes:

[0021] S401, based on the real-time state of charge and state of charge limit of electrochemical energy storage in the energy storage system, calculate the upper limit and lower limit of frequency regulation power of the energy storage battery after correction according to the following formulas.

[0022]

[0023]

[0024] In the above formula, and These are the corrected upper and lower limits of frequency regulation power for energy storage batteries, respectively, P b,N S represents the rated charge and discharge power of the energy storage power station. oc This indicates the real-time state of charge of the energy storage system. S oc,low S oc,high and These represent the preset minimum, low, high, and maximum values ​​of the state of charge;

[0025] S402, based on the corrected upper and lower limits of the frequency regulation power of the energy storage battery, the frequency regulation output of the electrochemical energy storage system is calculated using the following formula:

[0026]

[0027] Wherein, ΔP b This indicates the frequency regulation output of the electrochemical energy storage system. and These are the adjusted upper and lower limits of frequency regulation power for energy storage batteries. A represents the low-frequency signal indicating the frequency modulation range deviation. ce This represents the area control deviation signal ACE.

[0028] Optionally, the calculation function expression for the real-time state of charge of the energy storage system is:

[0029]

[0030] In the above formula, S oc C represents the real-time state of charge of the energy storage system. ini ΔP represents the initial capacity of the electrochemical energy storage system. e (t) represents the final output of the energy storage system, C N This indicates the rated capacity of the energy storage system.

[0031] Optionally, when obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit respectively, the calculation function expression for the frequency regulation output of the traditional frequency regulation unit is:

[0032]

[0033] Wherein, ΔP g This indicates the frequency modulation output of a traditional frequency modulation unit. ΔP represents the low-frequency signal, denoted as the low-frequency component allocated to electrochemical energy storage and conventional frequency regulation units. b This indicates the frequency regulation output of the electrochemical energy storage system.

[0034] Furthermore, the present invention also provides an automatic power generation control system with the participation of composite energy storage resources, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the automatic power generation control method with the participation of composite energy storage resources.

[0035] Furthermore, the present invention also provides a computer-readable storage medium storing a computer program, the computer program being programmed or configured by a microprocessor to execute the automatic power generation control method involving the composite energy storage resources.

[0036] Compared with existing technologies, the present invention has the following main advantages: The automatic power generation control method of the present invention with the participation of composite energy storage resources includes obtaining the regional control deviation signal ACE based on the regional exchange power deviation and frequency deviation; obtaining the high-frequency component and low-frequency component of frequency regulation demand based on the regional control deviation signal ACE; using flywheel energy storage of the energy storage system to undertake the high-frequency component of frequency regulation demand; and using electrochemical energy storage and traditional frequency regulation units to undertake the low-frequency component of frequency regulation demand. The present invention can take into account the technical characteristics of flywheel energy storage and electrochemical energy storage respectively, allocating the high-frequency component of frequency regulation demand to the flywheel energy storage system, and having the low-frequency component jointly undertaken by the electrochemical energy storage system and the traditional frequency regulation unit. On the other hand, considering that battery overcharging and over-discharging will affect the lifespan of electrochemical energy storage, the maximum frequency regulation output of the electrochemical energy storage system can be corrected by real-time state of charge, which can achieve complementary advantages between various frequency regulation power sources. By applying power-type flywheel energy storage and energy-type electrochemical energy storage in combination for grid frequency regulation, it can achieve complementarity in the capacity and power of different types of energy storage, as well as complementarity in economic cost and life cycle. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the basic process of the method in an embodiment of the present invention.

[0038] Figure 2 This is a control block diagram of the automatic power generation control system for power grids according to an embodiment of the present invention.

[0039] Figure 3 This is a simplified simulation model diagram of the energy storage system in an embodiment of the present invention.

[0040] Figure 4 This is a schematic diagram of the all-day regional control deviation variation curve in an embodiment of the present invention.

[0041] Figure 5 This is a schematic diagram of the frequency regulation demand spectrum analysis results of an actual power system for a certain hour in an embodiment of the present invention.

[0042] Figure 6 This is a schematic diagram of the high-frequency and low-frequency fluctuation components of the actual hourly frequency regulation demand of the power distribution network in an embodiment of the present invention.

[0043] Figure 7 This is a schematic diagram illustrating the proportion of high-frequency components in the hourly frequency modulation demand throughout the day in an embodiment of the present invention.

[0044] Figure 8 This is a schematic diagram of the strategy for separating high-frequency and low-frequency signals in an embodiment of the present invention.

[0045] Figure 9 This is a schematic diagram of the division of the state of charge interval in an embodiment of the present invention.

[0046] Figure 10This is a schematic diagram of the upper and lower limits of the electrochemical energy storage frequency modulation power after state of charge correction in an embodiment of the present invention.

[0047] Figure 11 This is a schematic diagram of the continuous load disturbance curve in an embodiment of the present invention.

[0048] Figure 12 This is a schematic diagram of the frequency fluctuation curve in an embodiment of the present invention.

[0049] Figure 13 This is a schematic diagram of the unit output curve in an embodiment of the present invention.

[0050] Figure 14 This is a schematic diagram of the power output curve of the energy storage system in an embodiment of the present invention.

[0051] Figure 15 This is a schematic diagram of the state of charge change curve of the energy storage system in an embodiment of the present invention. Detailed Implementation

[0052] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The specific embodiments described herein are merely illustrative of the invention and not intended to limit it. It should also be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0053] like Figure 1 As shown, the automatic power generation control method with the participation of composite energy storage resources in this embodiment includes:

[0054] S101, based on the inter-regional exchange power deviation ΔP tie The area control deviation signal ACE is obtained by measuring the frequency deviation Δf.

[0055] S102 obtains the high-frequency and low-frequency components of frequency regulation demand based on the regional control deviation signal ACE. The flywheel energy storage of the energy storage system is used to handle the high-frequency components of frequency regulation demand, while electrochemical energy storage and traditional frequency regulation units (power plants) are used to handle the low-frequency components of frequency regulation demand.

[0056] The control methods for energy storage power stations participating in secondary frequency regulation are generally based on two allocation modes: Area Control Deviation (ACE) and Area Regulation Requirements (ARR) demand signals. The main difference between ACE and ARR is that the latter uses a proportional-integral controller for conversion. Then, based on different participation factors, the ACE or ARR signal is allocated to the frequency regulation power supply. To maximize the advantages of rapid frequency regulation of energy storage power stations, this embodiment adopts an automatic generation control method based on ACE signals. Typical application scenarios for energy storage systems participating in grid automatic generation control include joint frequency regulation between energy storage systems and power plants (traditional frequency regulation units). Figure 2 This is the control block diagram of the automatic generation control system for the power grid in this embodiment, where e,i represent the energy storage system, and G... g,j This refers to a traditional frequency regulation unit (power plant). See also... Figure 2 The control strategy in step S102 is implemented through the AGC controller. Furthermore, the functional expression for obtaining the area control deviation signal ACE in step S101 is:

[0057] A ce =ΔP tie +BΔf,

[0058] In the above formula, A ce The region control deviation signal ACE is represented by B, where B represents the frequency deviation coefficient and ΔP represents the inter-regional power exchange deviation. tie The difference between the inter-regional exchange power value and the rated value is given by Δf, and the frequency deviation is the difference between the system frequency value and the rated value.

[0059] This embodiment uses a method based on historical data statistics to determine frequency regulation demand. The ACE value of a certain actual automatic generation control system within a day is as follows: Figure 4 As shown. The frequency domain distribution of frequency modulation demand is analyzed using Discrete Fourier Transform. For a discrete N-point sequence x(n), its Discrete Fourier Transform function expression is:

[0060]

[0061] In the above formula, X(k) is the result of Discrete Fourier Analysis (DFT), which represents Offline Fourier Analysis (DFT). x(n) is the input signal, e is the natural constant, j is the imaginary unit, n is the number of time-domain signal sequences, N is the number of sampling points, and k is the number of frequency-domain signal sequences. When k = 0, it corresponds to the DC component. If the sampling time interval is Δt, according to the sampling theorem, the highest frequency of the spectrum obtained by Discrete Fourier Analysis is 1 / 2Δt Hertz. Figure 5 The spectrum analysis results for a certain hour are shown, with a sampling interval of 5 seconds. Using the frequency trial method and inverse Fourier transform, a schematic diagram of the high-frequency and low-frequency component fluctuations of the actual system's frequency modulation requirement for a certain hour is obtained, as shown below. Figure 6 As shown. Furthermore, the proportion of high-frequency components in the hourly frequency modulation demand for a representative day is statistically analyzed, such as... Figure 7 As shown.

[0062] In this embodiment, step S102 includes:

[0063] S201, the discrete Fourier transform of the regional control deviation signal ACE is used to obtain the frequency domain distribution of the frequency modulation requirement, and the boundary point between high and low frequencies in the frequency domain distribution is determined.

[0064] S202 divides the frequency domain distribution into high and low frequencies based on the high-low frequency boundary point, thereby obtaining the high-frequency and low-frequency components of the frequency regulation requirement. The flywheel energy storage of the energy storage system undertakes the high-frequency component of the frequency regulation requirement, while electrochemical energy storage and traditional frequency regulation units undertake the low-frequency component of the frequency regulation requirement.

[0065] Based on the respective technical characteristics of flywheel energy storage and electrochemical energy storage, the strategy design for automatic generation control of the power system considers dividing the frequency regulation demand into high-frequency and low-frequency components. The filtering frequency is determined by using a frequency trial method based on historical data. Flywheel energy storage is used to handle the high-frequency component, while electrochemical energy storage and traditional frequency regulation units handle the low-frequency component.

[0066] like Figure 8 As shown, step S202 in this embodiment includes:

[0067] S301, the area control deviation signal ACE is low-pass filtered by a low-pass filter that uses the high-low frequency boundary as the cutoff frequency to obtain the low-frequency component ACE. low ;

[0068] S302, subtract the low-frequency component ACE from the area control deviation signal ACE. low Obtain high-frequency component ACE high ACE of high frequency components high Limiting is applied to the high-frequency component A allocated to flywheel energy storage. ce，hight ;

[0069] S303 subtracts the high-frequency component allocated to the energy storage system from the area control deviation signal ACE to obtain the low-frequency component A allocated to the electrochemical energy storage and the traditional frequency regulation unit. ce，low ;

[0070] S304, using flywheel energy storage in an energy storage system to handle the high-frequency component A of frequency regulation requirements. ce，hight Electrochemical energy storage and traditional frequency regulation units handle the low-frequency component A of frequency regulation requirements. ce，low .

[0071] In this embodiment, obtaining the frequency deviation Δf in step S101 includes: firstly, obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit, wherein the energy storage system includes flywheel energy storage and electrochemical energy storage and the traditional frequency regulation unit; then, obtaining the frequency regulation output of the energy storage system and the traditional unit, and the power exchange deviation ΔP between each region. tie and the continuous load disturbance ΔP of the system L The system power deviation is obtained by summing the results. This deviation is then used to control the synchronous generator to generate electricity, thereby obtaining the frequency deviation Δf. In this embodiment, the transfer function of the synchronous generator is:

[0072]

[0073] Where M represents the inertia constant of the synchronous generator, and S represents the load damping constant.

[0074] In this embodiment, when obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit respectively, the acquisition of the frequency regulation output of the electrochemical energy storage system includes:

[0075] S401, based on the real-time state of charge and state of charge limit of electrochemical energy storage in the energy storage system, calculate the upper limit and lower limit of frequency regulation power of the energy storage battery after correction according to the following formulas.

[0076]

[0077]

[0078] In the above formula, and These are the corrected upper and lower limits of frequency regulation power for energy storage batteries, respectively, P b，N S represents the rated charge and discharge power of the energy storage power station. oc S represents the real-time state of charge of the energy storage system. oc，min S oc，low S oc，high and S oc，max These represent the minimum, low, high, and maximum values ​​of the preset state of charge, distributed as follows: Figure 9 As shown;

[0079] S402, based on the corrected upper and lower limits of the frequency regulation power of the energy storage battery, the frequency regulation output of the electrochemical energy storage system is calculated using the following formula:

[0080]

[0081] Wherein, ΔP b This indicates the frequency regulation output of the electrochemical energy storage system. and These are the corrected upper and lower limits of frequency regulation power for energy storage batteries, respectively. ce，low A represents the low-frequency signal indicating the frequency modulation range deviation. ce This represents the area control deviation signal ACE. Since overcharging and over-discharging can affect the lifespan of energy storage batteries, the output of an energy storage power station needs to consider the limitations of the state of charge (SOC) during operation. Therefore, the SOC is divided into intervals, specifically as follows: Figure 9 As shown. The corrected upper and lower limits of frequency regulation power for each energy storage power station are calculated based on the State of Charge (SOC) range, as follows: Figure 10 As shown. Based on the corrected upper and lower limits of frequency regulation power, the electrochemical energy storage system prioritizes responding to the low-frequency components of the frequency regulation demand. When the energy storage frequency regulation capacity is insufficient, the remaining portion is regulated by the traditional frequency regulation unit.

[0082] In research on energy storage systems' participation in grid frequency regulation, the main focus is on the external output characteristics of the energy storage. Therefore, the energy storage system can be modeled using a first-order inertial element and control gain. A simplified simulation model of the energy storage system is as follows: Figure 3 As shown. Where, T e K represents the time constant of the energy storage system, determined by its own characteristics. e For control signal ΔP c (s) and the final output ΔP of the energy storage system e The conversion factor between (s); C N S represents the rated capacity of the energy storage system. oc，in Let S be the initial value of the energy storage state of charge, and S is given. oc，in =C ini / C N S oc The control signal ΔP represents the real-time state of charge of the energy storage system. c (s) after the transfer function model K e / (1+T e The final output ΔP of the energy storage system is obtained after limiting the amplitude (s) and amplitude. e (s), after a 1 / 3600s delay, the hourly charging and discharging power of the energy storage system is obtained, and this power can be used to calculate the real-time state of charge (SOC) of the energy storage system. In this embodiment, the calculation function expression for the real-time SOC of the energy storage system is:

[0083]

[0084] In the above formula, S oc C represents the real-time state of charge of the energy storage system. ini ΔP represents the initial capacity of the electrochemical energy storage system. e (t) represents the final output of the energy storage system, C N This represents the rated capacity of the energy storage system. In this embodiment, the final output power ΔP of the energy storage system is defined. e (t) is positive during discharge and negative during charging.

[0085] In this embodiment, when obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit respectively, the calculation function expression of the frequency regulation output of the traditional frequency regulation unit is:

[0086]

[0087] In the above formula, ΔP g A represents the frequency modulation output of a traditional frequency modulation unit. ce，low ΔP represents the low-frequency signal, denoted as the low-frequency component allocated to electrochemical energy storage and conventional frequency regulation units. b This indicates the frequency regulation output of the electrochemical energy storage system. Figure 2 G ing，j The transfer function of a traditional frequency-regulating generator unit generally includes two parts: the governor and the prime mover. After simplification, both can be represented by a first-order inertial model. For example, the transfer function of a traditional thermal power unit can be simplified as follows:

[0088] G g (s)=1 / [(1+T g s)(1+T q s)]

[0089] In the above formula, T g T is the time constant of the speed controller. q The prime mover time constant.

[0090] also, Figure 11 This is a schematic diagram of the continuous load disturbance curve in an embodiment of the present invention. The curve is the load curve after continuous disturbance is added to the system. Figure 12 This is a schematic diagram of frequency fluctuation curves in an embodiment of the present invention. Curve Case 1f is the frequency fluctuation curve of the composite energy storage system provided in the embodiment of the present invention participating in the automatic power generation control of the grid. Curve Case 2f is the frequency fluctuation curve of only a single electrochemical energy storage system participating in the automatic power generation control of the grid in a certain proportion. Figure 13 This is a schematic diagram of the unit output curve in an embodiment of the present invention. Curve Case1Pg is the output curve of a conventional unit under the automatic power generation control of the grid with the participation of the composite energy storage system provided in the embodiment of the present invention. Curve Case2Pg is the output curve of a conventional unit under the automatic power generation control of the grid with only a single electrochemical energy storage system participating in a certain proportion. Figure 14 This is a schematic diagram of the power output curves of the energy storage system in the embodiments of the present invention. Curve Case1Pfly is the power output curve of the flywheel energy storage system under the automatic power generation control of the grid provided in the embodiments of the present invention. Curve Case1Pbatt is the power output curve of the electrochemical energy storage system under the automatic power generation control of the grid provided in the embodiments of the present invention. Curve Case2Pbatt is the power output curve of the electrochemical energy storage system under the automatic power generation control of the grid with only a single electrochemical energy storage system participating in a certain proportion. Figure 15 This is a schematic diagram of the state of charge (SOC) change curves of the energy storage system in this embodiment of the invention. Curve Case1Soc,batt is the SOC change curve of the electrochemical energy storage system under automatic grid generation control provided by the composite energy storage system in this embodiment of the invention. Curve Case1Soc,fly is the SOC change curve of the flywheel energy storage system under automatic grid generation control provided by the composite energy storage system in this embodiment of the invention. Curve Case2Pbatt is the SOC curve of the electrochemical energy storage system under automatic grid generation control with only a single electrochemical energy storage system participating in a fixed proportion. Figure 12It can be seen that the overall frequency fluctuation amplitude of the composite energy storage system participating in the automatic generation control of the power grid is smaller; by Figure 13 It can be seen that the frequency regulation mileage of traditional generating units participating in the automatic generation control of the grid under the composite energy storage system is relatively small, and the demand for frequency regulation reserve capacity is also relatively small; by Figure 14 It can be seen that the flywheel energy storage and battery energy storage systems participating in the automatic generation control of the grid under the composite energy storage system assume corresponding responsibilities for the high-frequency and low-frequency components of frequency regulation demand, which is consistent with their respective operating characteristics. Only the electrochemical energy storage system participating in the automatic generation control of the grid under the single electrochemical energy storage system under the fixed proportion bears the frequent fluctuations in frequency regulation demand alone. Figure 15 It can be seen that the state of charge (SOC) of flywheel energy storage under automatic grid generation control, involving the composite energy storage system, fluctuates around the initial value of 0.3, while the overall trend of electrochemical energy storage is an initial decrease followed by a significant rebound. Analysis of these results shows that under automatic grid generation control involving the composite energy storage system, flywheel and battery energy storage respectively assume corresponding responsibilities for the high-frequency and low-frequency components of frequency regulation demand, conforming to their respective operating characteristics and effectively reducing the frequency regulation reserve of traditional units and the frequency fluctuation of the grid. Furthermore, because the electrochemical energy storage system establishes a frequency regulation output function relationship based on SOC correction, it plays a certain role in maintaining the SOC of electrochemical energy storage. By combining different types of energy storage systems to participate in automatic grid generation control, the impact of overcharging and over-discharging on battery energy storage lifespan can be eliminated, and the rapid response output characteristics of flywheel energy storage can be fully utilized.

[0091] In summary, this embodiment provides an automatic power generation control method involving composite energy storage resources. This method involves a composite energy storage system composed of power-type flywheel energy storage and energy-type electrochemical energy storage participating in the automatic power generation control of the power grid. Combining historical data on frequency regulation demand, it uses Discrete Fourier Transform to analyze the characteristics of regional control deviation in the frequency domain, rationally determining the filtering frequency within the frequency fluctuation range. Flywheel energy storage handles the high-frequency components, while electrochemical energy storage and traditional frequency regulation units handle the low-frequency components. Based on the premise of priority energy storage scheduling, and considering that overcharging and over-discharging will affect the lifespan of electrochemical energy storage, the maximum frequency regulation output of electrochemical energy storage is corrected in real-time using state of charge sensing. This embodiment's automatic power generation control method involving composite energy storage resources can take into account the respective technical characteristics of flywheel energy storage and electrochemical energy storage. It allocates the high-frequency components of frequency regulation demand to the flywheel energy storage system, while the low-frequency components are shared by the electrochemical energy storage system and traditional frequency regulation units. Furthermore, considering that overcharging and over-discharging of batteries will affect the lifespan of electrochemical energy storage, the maximum frequency regulation output of the electrochemical energy storage system is corrected in real-time using state of charge, enabling complementary advantages among various frequency regulation power sources.

[0092] Furthermore, this embodiment also provides an automatic power generation control system with the participation of composite energy storage resources, including a microprocessor and a memory interconnected, wherein the microprocessor is programmed or configured to execute the aforementioned automatic power generation control method with the participation of composite energy storage resources. Additionally, this embodiment also provides a computer-readable storage medium storing a computer program for being programmed or configured by the microprocessor to execute the aforementioned automatic power generation control method with the participation of composite energy storage resources.

[0093] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable apparatus for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0094] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. An automatic power generation control method involving composite energy storage resources, characterized in that, include: S101, based on the inter-regional exchange power deviation Frequency deviation Acquire the area control deviation signal ACE; S102, based on the regional control deviation signal ACE, obtains the high-frequency and low-frequency components of the frequency regulation demand, uses the flywheel energy storage of the energy storage system to bear the high-frequency component of the frequency regulation demand, and electrochemical energy storage and traditional frequency regulation units to bear the low-frequency component of the frequency regulation demand. Frequency deviation in step S101 The acquisition includes: firstly, acquiring the frequency regulation output of the energy storage system and the traditional frequency regulation unit, where the energy storage system includes flywheel energy storage and electrochemical energy storage, and the traditional frequency regulation unit; then, acquiring the frequency regulation output of the energy storage system and the traditional unit, and the power exchange deviation between different areas. and continuous load disturbances of the system The system power deviation is obtained by summing the results. The system power deviation is then used to control the synchronous generator to generate electricity, thereby obtaining the frequency deviation. When obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit respectively, the acquisition of the frequency regulation output of the electrochemical energy storage system includes: S401, based on the real-time state of charge and state of charge limit of electrochemical energy storage in the energy storage system, calculate the upper limit and lower limit of frequency regulation power of the energy storage battery after correction according to the following formulas. ， ， In the above formula, and These are the adjusted upper and lower limits of frequency regulation power for energy storage batteries. This indicates the rated charging and discharging power of the energy storage power station. This indicates the real-time state of charge of the energy storage system. , , and These represent the preset minimum, low, high, and maximum values ​​of the state of charge; S402, based on the corrected upper and lower limits of the frequency regulation power of the energy storage battery, the frequency regulation output of the electrochemical energy storage system is calculated using the following formula: in, This indicates the frequency regulation output of the electrochemical energy storage system. and These are the adjusted upper and lower limits of frequency regulation power for energy storage batteries. This represents the low-frequency component allocated to electrochemical energy storage and traditional frequency regulation units. This represents the area control deviation signal ACE.

2. The automatic power generation control method with the participation of composite energy storage resources according to claim 1, characterized in that, The functional expression for obtaining the area control deviation signal ACE in step S101 is: ， In the above formula, This represents the area control deviation signal ACE. B This represents the frequency deviation coefficient and the inter-regional power exchange deviation. The frequency deviation is the difference between the inter-regional exchange power value and the rated value. This is the difference between the system frequency value and the rated value.

3. The automatic power generation control method with the participation of composite energy storage resources according to claim 1, characterized in that, Step S102 includes: S201, the discrete Fourier transform of the regional control deviation signal ACE is used to obtain the frequency domain distribution of the frequency modulation requirement, and the boundary point between high and low frequencies in the frequency domain distribution is determined. S202 divides the frequency domain distribution into high and low frequencies based on the high-low frequency boundary point, thereby obtaining the high-frequency and low-frequency components of the frequency regulation requirement. The flywheel energy storage of the energy storage system undertakes the high-frequency component of the frequency regulation requirement, while electrochemical energy storage and traditional frequency regulation units undertake the low-frequency component of the frequency regulation requirement.

4. The automatic power generation control method with the participation of composite energy storage resources according to claim 3, characterized in that, Step S202 includes: S301, the area control deviation signal ACE is low-pass filtered by a low-pass filter that uses the high-low frequency boundary as the cutoff frequency to obtain the low-frequency component ACE. low ; S302, subtract the low-frequency component ACE from the area control deviation signal ACE. low Obtain high-frequency component ACE high ACE of high frequency components high Limiting is applied to the high-frequency components allocated to flywheel energy storage. ; S303 subtracts the high-frequency component allocated to the energy storage system from the area control deviation signal ACE to obtain the low-frequency component allocated to the electrochemical energy storage and the traditional frequency regulation unit. ; S304 uses a flywheel energy storage system to handle the high-frequency components of frequency regulation requirements. Electrochemical energy storage and traditional frequency regulation units handle the low-frequency components allocated to them. .

5. The automatic power generation control method with the participation of composite energy storage resources according to claim 1, characterized in that, The calculation function expression for the real-time state of charge of the energy storage system is as follows: In the above formula, This indicates the real-time state of charge of the energy storage system. Indicates the initial capacity of the electrochemical energy storage system. Indicates the final output of the energy storage system. This indicates the rated capacity of the energy storage system.

6. The automatic power generation control method with the participation of composite energy storage resources according to claim 1, characterized in that, When obtaining the frequency regulation output of the energy storage system and the traditional frequency regulation unit respectively, the calculation function expression of the frequency regulation output of the traditional frequency regulation unit is: in, This indicates the frequency modulation output of a traditional frequency modulation unit. This represents the low-frequency component allocated to electrochemical energy storage and traditional frequency regulation units. This indicates the frequency regulation output of the electrochemical energy storage system.

7. An automatic power generation control system with the participation of composite energy storage resources, comprising a microprocessor and a memory interconnected, characterized in that, The microprocessor is programmed or configured to execute the automatic power generation control method with the participation of composite energy storage resources as described in any one of claims 1 to 6.

8. A computer-readable storage medium storing a computer program, characterized in that, The computer program is used to be programmed or configured by a microprocessor to execute the automatic power generation control method with the participation of composite energy storage resources as described in any one of claims 1 to 6.

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