VSG-based energy storage power station adaptive inertial support control method, system, equipment and medium

Abstract

The invention provides a VSG-based energy storage power station adaptive inertial support control method, system and device and a medium, and relates to the technical field of energy storage power station control. The method comprises the steps that power grid operation parameters and energy storage battery pack state parameters are collected, the power grid operation parameters comprise the power grid frequency and the frequency change rate, and the energy storage battery pack state parameters comprise the remaining electric quantity and the battery temperature; calculating frequency deviation according to the power grid frequency and the power grid rated frequency, judging the power grid disturbance level according to the frequency change rate and the frequency deviation, and judging the battery safety state according to the residual electric quantity and the battery temperature; determining a disturbance adaptation coefficient according to the power grid disturbance level, determining a battery state correction coefficient according to the battery safety state, and dynamically optimizing an inertia time constant and a damping coefficient of the VSG based on the disturbance adaptation coefficient and the battery state correction coefficient; based on the inertia time constant and the damping coefficient, basic inertia support power is calculated in combination with a VSG rotor motion equation, and the basic inertia support power and a frequency modulation component of the AGC instruction are subjected to cooperative processing to obtain a final power instruction; and issuing the final power instruction to the energy storage converter for execution.

Description

Technical Field

[0001] This application relates to the field of energy storage power station control technology, and in particular to an adaptive inertial support control method, system, equipment and medium for energy storage power stations based on VSG, which is suitable for power systems with a high proportion of new energy grid connection and can improve grid frequency stability. Background Technology

[0002] With the large-scale application of new energy power generation technologies such as photovoltaics and wind power, the proportion of synchronous generators in the power system is constantly decreasing, leading to a significant decline in grid inertia. When traditional energy storage power stations are connected to the grid through energy storage converters (PCS), they mostly adopt constant power control mode, which can only output active and reactive power according to dispatch instructions. They cannot provide inertial support for the grid, resulting in increased frequency fluctuation amplitude and prolonged recovery time when the grid is subjected to disturbances such as load fluctuations and sudden changes in new energy output, seriously threatening the safe and stable operation of the grid.

[0003] Virtual synchronous generator (VSG) technology simulates the rotor inertia, damping characteristics, and speed and voltage regulation mechanisms of a synchronous generator in the PCS control strategy, enabling energy storage power stations to possess external characteristics similar to a synchronous generator. This allows them to provide inertial support and frequency regulation services to the power grid, making it a core technological direction for solving the "low inertia" problem of new energy power grids. However, existing technologies have the following drawbacks: Fixed inertial parameters: In existing VSG control methods, the inertial time constant and damping coefficient are mostly designed with fixed values ​​and cannot be dynamically adjusted. This can easily lead to over-control when the grid frequency fluctuates slightly, and it is difficult to provide sufficient inertial support when the frequency fluctuates significantly, resulting in poor adaptability.

[0004] Insufficient coordination of energy storage status: The control strategy is not fully integrated with the status parameters of the energy storage power station.

[0005] AGC commands and inertial support coupling conflict: In existing methods, the inertial support function of VSG and the grid AGC requirements are not precisely coordinated. During the inertial support process, the superposition interference of inertial response and AGC commands is prone to occur, resulting in a decrease in frequency regulation accuracy. Summary of the Invention

[0006] In view of this, this application provides an adaptive inertial support control method, system, equipment and medium for VSG-based energy storage power stations, which solves the above-mentioned technical problems.

[0007] In a first aspect, embodiments of this application provide an adaptive inertial support control method for energy storage power stations based on VSG, including: Collect grid operating parameters and energy storage battery pack status parameters. The grid operating parameters include grid frequency and frequency change rate, and the energy storage battery pack status parameters include remaining power and battery temperature. The frequency deviation is calculated based on the grid frequency and the grid rated frequency. The grid disturbance level is determined based on the frequency change rate and frequency deviation. The battery safety status is determined based on the remaining power and battery temperature. The disturbance adaptation coefficient is determined based on the grid disturbance level, the battery state correction coefficient is determined based on the battery safety status, and the inertial time constant and damping coefficient of the VSG are dynamically optimized based on the disturbance adaptation coefficient and the battery state correction coefficient. Based on the inertial time constant and damping coefficient, combined with the VSG rotor motion equation, the power of the foundation inertial support is calculated, and the power of the foundation inertial support is processed in conjunction with the frequency modulation component of the AGC command to obtain the final power command. The final power command is sent to the energy storage converter for execution.

[0008] Secondly, embodiments of this application provide an adaptive inertial support control system for a VSG-based energy storage power station, comprising: The power grid status monitoring module is used to collect power grid operating parameters, including power grid frequency and frequency change rate. The battery status management module is used to monitor the status parameters of the energy storage battery pack, including the remaining power and battery temperature. The VSG control module includes a parameter optimization unit, a rotor motion equation calculation unit, and a power coordination unit. The parameter optimization unit calculates the frequency deviation based on the grid frequency and the grid's rated frequency, determines the grid disturbance level based on the frequency change rate and frequency deviation, determines the battery safety status based on the remaining charge and battery temperature, determines the disturbance adaptation coefficient based on the grid disturbance level, determines the battery status correction coefficient based on the battery safety status, and dynamically optimizes the VSG's inertial time constant and damping coefficient based on the disturbance adaptation coefficient and battery status correction coefficient. The rotor motion equation calculation unit calculates the basic inertial support power based on the inertial time constant and damping coefficient, combined with the VSG rotor motion equation. The power coordination unit coordinates the basic inertial support power with the frequency modulation component of the AGC command to obtain the final power command. The execution module is used to send the final power command to the energy storage converter for execution.

[0009] Thirdly, embodiments of this application provide a computer device including a processor and a memory, the memory storing programs or instructions that can run on the processor, the programs or instructions implementing the steps of the method as described in the first aspect when executed by the processor.

[0010] Fourthly, embodiments of this application provide a readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the method as described in the first aspect.

[0011] The adaptive inertial support control method, system, device, and medium for energy storage power stations based on VSG in this application embodiment can dynamically adjust the VSG inertial parameters and damping parameters according to different power grid disturbance scenarios, thereby improving the accuracy of inertial support. This solves the drawbacks of traditional fixed parameters, which are prone to over-control when the power grid frequency fluctuates slightly, and are unable to provide sufficient inertial support when it fluctuates significantly, resulting in poor adaptability. By integrating the energy storage battery state parameters, it ensures battery safety while providing inertial support, avoiding overcharging or over-discharging of the battery due to excessively high or low battery SOC, thus shortening battery life. It also achieves coordinated control of inertial support and AGC command frequency modulation components, improving the accuracy of power grid frequency regulation and reducing the amplitude of frequency fluctuations.

[0012] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0013] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 One of the flowcharts of the adaptive inertial support control method for energy storage power stations based on VSG according to an embodiment of this application is shown; Figure 2 This is a second schematic flowchart of the adaptive inertial support control method for energy storage power stations based on VSG, according to an embodiment of this application. Figure 3 A frequency comparison diagram of adaptive inertial control and fixed parameter inertial control under the same disturbance is shown in the embodiment of this application; Figure 4 A structural block diagram of an adaptive inertial support control system for a VSG-based energy storage power station, according to an embodiment of this application, is shown. Detailed Implementation

[0014] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0015] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0016] The existing VSG-based adaptive inertial support control method for energy storage power stations has the following problems: (1) Fixed inertial parameters: In the existing VSG control method, the inertial time constant and damping coefficient are mostly designed with fixed values, which cannot be dynamically adjusted according to the grid operating status. When the grid frequency fluctuates slightly, it is easy to cause over-control, and when it fluctuates significantly, it is difficult to provide sufficient inertial support, resulting in poor adaptability. (2) Insufficient coordination of energy storage status: The control strategy is not fully combined with the state parameters such as the remaining battery charge (SOC) and charging and discharging power limit of the energy storage power station. When the battery SOC is too high or too low, forcibly providing inertial support may lead to overcharging and over-discharging of the battery, shortening the battery life, or even causing safety risks. (3) Coupling conflict between AGC commands and inertial support: In the existing method, the inertial support function of VSG and the grid AGC demand are not precisely coordinated. During the participation of inertial support, the superposition interference of inertial response and AGC commands is easy to occur, resulting in a decrease in frequency regulation accuracy. Considering the above problems, the embodiments of this application provide an adaptive inertial support control scheme for energy storage power stations based on VSG, which can solve the above problems.

[0017] The following description, in conjunction with the accompanying drawings, details the adaptive inertial support control method, system, equipment, and medium for VSG-based energy storage power stations provided in this application through specific embodiments and application scenarios. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0018] This application provides an adaptive inertial support control method for energy storage power stations based on VSG, such as... Figure 1 and Figure 2 As shown, the method includes: Step 101: Collect grid operating parameters and energy storage battery pack status parameters. The grid operating parameters include grid frequency and frequency change rate, and the energy storage battery pack status parameters include remaining power and battery temperature.

[0019] In this step, multi-dimensional status information is collected. Real-time acquisition of grid operating parameters, including grid frequency f and frequency change rate df / dt, is performed. Additionally, energy storage battery pack status parameters are collected, including remaining charge (SOC), battery temperature T, and charge / discharge power limits Pmin / Pmax. The acquisition frequency is no less than 100Hz to ensure the real-time nature of the status information.

[0020] Step 102: Calculate the frequency deviation based on the grid frequency and the grid rated frequency, determine the grid disturbance level based on the frequency change rate and frequency deviation, and determine the battery safety status based on the remaining power and battery temperature.

[0021] Three levels of power grid disturbance are pre-defined: Level 1, Level 2, and Level 3. Each disturbance level corresponds to a different rate of frequency change and frequency deviation. For example, Level 1 disturbances correspond to an absolute value of the rate of frequency change less than or equal to a first rate of change threshold and a frequency deviation less than or equal to a first deviation threshold; Level 2 disturbances correspond to an absolute value of the rate of frequency change greater than the first rate of change threshold and less than or equal to a second rate of change threshold, and a frequency deviation greater than the first deviation threshold and less than or equal to the second deviation threshold; Level 3 disturbances correspond to an absolute value of the rate of frequency change greater than the second rate of change threshold and a frequency deviation greater than the second deviation threshold.

[0022] The first rate of change threshold is less than the second rate of change threshold, and the first deviation threshold is less than the second deviation threshold. The first rate of change threshold can be set to 0.1 Hz / s, and the second rate of change threshold can be set to 0.5 Hz / s; the first deviation threshold can be set to 0.1 Hz, and the second deviation threshold can be set to 0.3 Hz.

[0023] That is, based on the power grid frequency change rate df / dt and the frequency deviation Δf, Δf=|f-f0|, where f0 is the rated frequency of the power grid, for example, 50Hz, the power grid disturbance is divided into three levels: First-order perturbation (micro-perturbation): |df / dt|≤0.1Hz / s and Δf≤0.1Hz; Second-order disturbance (intermediate disturbance): 0.1Hz / s < |df / dt| ≤ 0.5Hz / s and 0.1Hz < Δf ≤ 0.3Hz; Level 3 disturbance (strong disturbance): |df / dt|>0.5Hz / s or Δf>0.3Hz.

[0024] Furthermore, three battery safety states are pre-defined: Level 1, Level 2, and Level 3. Each safety state corresponds to different remaining battery capacity and battery temperature. For example, Level 1 corresponds to the remaining battery capacity being in the second range and the battery temperature being in the first range; Level 2 corresponds to the remaining battery capacity being in the first or third range and the battery temperature being in the first range; Level 3 corresponds to the remaining battery capacity not being in the first, second, or third range, or the battery temperature not being in the first range.

[0025] The value in the second power range is greater than the value in the first power range and less than the value in the third power range. The first power range can be set to [20%, 40%], the second power range can be set to [40%, 60%], the third power range can be set to (60%, 80%), and the first temperature range can be set to [15℃, 35℃].

[0026] In other words, based on the remaining state of charge (SOC) and battery temperature (T), the battery safety status is divided into three levels: Level 1 state: SOC∈[40%, 60%], and T∈[15℃, 35℃]; Secondary state: SOC∈[20%, 40%) or (60%, 80%), and T∈[15℃, 35℃]; Level 3 State: SOC [20%, 80%] or T [15℃, 35℃].

[0027] After determining the frequency change rate df / dt and the frequency deviation Δf, the power grid disturbance level can be determined according to the classification rules. Specifically, when the frequency change rate df / dt and the frequency deviation Δf satisfy |df / dt|≤0.1Hz / s and Δf≤0.1Hz, the power grid disturbance level is classified as Level 1; when the frequency change rate df / dt and the frequency deviation Δf satisfy 0.1Hz / s<|df / dt|≤0.5Hz / s and 0.1Hz<Δf≤0.3Hz, the power grid disturbance level is classified as Level 2; and when the frequency change rate df / dt and the frequency deviation Δf satisfy |df / dt|>0.5Hz / s or Δf>0.3Hz, the power grid disturbance level is classified as Level 3.

[0028] After determining the remaining state of charge (SOC) and battery temperature (T), the battery's safety state can be determined according to the battery safety state classification rules. Specifically, when SOC ∈ [40%, 60%] and T ∈ [15℃, 35℃], the battery safety state is classified as Level 1; when SOC ∈ [20%, 40%] or (60%, 80%) and T ∈ [15℃, 35℃], the battery safety state is classified as Level 2; and when SOC... [20%, 80%] or T At [15℃, 35℃], the battery safety status is determined to be Level 3.

[0029] In one embodiment, SOC [20%, 80%] or T The safety restriction mechanism can be triggered at [15℃, 35℃].

[0030] Step 103: Determine the disturbance adaptation coefficient based on the grid disturbance level, determine the battery state correction coefficient based on the battery safety status, and dynamically optimize the inertial time constant and damping coefficient of the VSG based on the disturbance adaptation coefficient and the battery state correction coefficient.

[0031] In this step, the disturbance adaptation coefficient k is determined based on the grid disturbance level. For example, when the disturbance is classified as Level 1, the disturbance adaptation coefficient k is 0.5 to 0.8; when it is classified as Level 2, the disturbance adaptation coefficient k is 1.0 to 1.2; and when it is classified as Level 3, the disturbance adaptation coefficient k is 1.2 to 1.5. The stronger the disturbance, the larger k is, providing stronger inertial support. Additionally, the battery state correction coefficient m is determined based on the battery safety state. For example, when the battery state is classified as Level 1, the battery state correction coefficient m is 1.0; when it is classified as Level 2, the battery state correction coefficient m is 0. The closer the SOC is to the boundary, the smaller m is, reducing the inertial support strength to protect the battery; when the battery state is classified as Level 3, the battery state correction coefficient m is 0, that is, when the SOC exceeds the boundary, m is 0, indicating that inertial support is suspended.

[0032] Furthermore, based on the disturbance adaptation coefficient, battery state correction coefficient, and preset reference inertial time constant J0 and reference damping coefficient D0, the inertial time constant J and damping coefficient D are dynamically optimized according to the dynamic adjustment model of VSG, ensuring that the damping coefficient and inertial parameters are matched in synergy. The dynamic adjustment model of inertial time constant J and damping coefficient D is as follows: J = J0 × k × m; D = D0 × k × (2 - m); Where J represents the inertial time constant, D represents the damping coefficient, J0 represents the reference inertial time constant, D0 represents the reference damping coefficient, k represents the disturbance adaptation coefficient, and m represents the battery state correction coefficient.

[0033] Step 104: Based on the inertial time constant and damping coefficient, and combined with the VSG rotor motion equation, calculate the basic inertial support power, and then process the basic inertial support power in conjunction with the frequency modulation component of the AGC command to obtain the final power command.

[0034] In this step, based on the VSG rotor motion equations, the power of the foundation inertial support, i.e., the active power command P of the foundation inertial support, is calculated. VSG0 :P VSG0 =(J×df / dt)+D×(f-f0), where (J×df / dt) is the inertial response power and D×(f-f0) is the damping adjustment power. Further, the basic inertial support power and the frequency modulation component of the AGC command are processed collaboratively to obtain the final power command.

[0035] In one embodiment of this application, the basic inertial support power and the frequency modulation component of the AGC command are processed collaboratively to obtain the final power command, including: The low-frequency and high-frequency components in the AGC command are separated by a low-pass filter, and the high-frequency components are superimposed on the basic inertial support power to obtain the inertial support power. The sum of the inertial support power and the low-frequency component is calculated as the final power command.

[0036] In this embodiment, the active power command, i.e., the AGC command P, is received from the power grid dispatch center. AGC This instruction includes the dynamic power demand required for grid frequency regulation, which is separated by a low-pass filter. AGC The low-frequency component P in AGC低 (Frequency modulation steady-state requirements) and high-frequency component P AGC高 (Disturbance transient demand), the high-frequency component P AGC高 Superimposed on P VSG0 This yields the inertial support power, which is the actual inertial support active power command P. VSG =P VSG0 +P AGC高 And, the low-frequency component P AGC低 As the basic power command, it forms the final power command P. f P f =P VSG +P AGC低 Achieving synergy between transient inertial support response and steady-state AGC frequency modulation control.

[0037] In one embodiment, a power limit verification function is also included: the battery state parameters also include the battery charge / discharge power limit P. min / P max Combined with the battery charging and discharging power limit P min / P max For the final power command P f =P VSG +P AGC低 Perform a verification to ensure P min ≤P f ≤P max Furthermore, it can be done beyond P.min and P max Amplitude limiting is applied at certain times.

[0038] Step 105: Send the final power command to the energy storage converter for execution.

[0039] In this step, the optimized final power command P is... f The control unit, which sends the data to the energy storage converter PCS, adjusts the power output through IGBT switching timing.

[0040] In one embodiment of this application, after the final power command is issued to the energy storage converter for execution, the method further includes: The output power of the energy storage converter and the grid frequency feedback value are collected in real time, and the control error is calculated. When the control error and frequency deviation meet the preset conditions, the inertial time constant and damping coefficient are re-optimized.

[0041] In this embodiment, the PCS output power P and the grid frequency feedback value f are acquired in real time, and the control error e = |PP| is calculated. f | / P f The frequency recovery deviation Δf = |f - f0|, when the preset conditions of e > 5% or Δf > 0.1Hz are met, return to step 103 to re-optimize the inertial parameters and damping coefficient; otherwise, adjust the control frequency deviation Δf to the target range according to the current inertial parameters and damping parameters.

[0042] In one specific embodiment of this application, the energy storage power station scale is: lithium battery energy storage system, SOC operating range of 20% to 80%, and rated charge and discharge power of 500kW; PCS parameters: adopts a three-level NPC topology, with a rated capacity of 500kVA; Monitoring equipment: voltage sensor with an accuracy of 0.2 class, frequency acquisition unit with a sampling rate of 1kHz, and battery temperature sensor with an accuracy of ±0.5℃; Initial state: grid frequency 50Hz, energy storage battery SOC=50%, temperature 25℃, PCS in standby state, VSG reference parameters J0=1s, D0=50kW / Hz; Disturbance occurred: The power grid experienced a sudden drop in frequency due to a sudden increase in load, with df / dt = -6Hz / s and Δf = 0.4Hz detected, which was determined to be a level 3 disturbance; the battery status was normal, m = 1.0; Parameter optimization: For a level 3 disturbance, k=1.4, the calculated J=1×1.4×1.0=1.4s, D=50×1.4×(2-1.0)=70kW / Hz; Power calculation: Inertial support power P VGC0=1.4×(-6)+70×(49.6-50)=-8.4-28=-36.4kW (the negative sign indicates discharge); Receive frequency modulation command P AGC =-300kW, after low-pass filtering, the low-frequency component -270kW and the high-frequency component -30kW are separated, and finally P f =-36.4+(-30)+(-270)=-336.4kW, within the battery discharge power limit of -500kW; Execution and feedback: The PCS discharges according to the command of -336.4kW. After 0.2s, the grid frequency rises back to 49.8Hz, Δf=0.2Hz, control error e=2%, and continues to operate; after 0.5s, the grid frequency recovers to 50Hz, and the inertial support ends.

[0043] Figure 3 The diagram shows a frequency comparison between the adaptive inertial control method of this application and the fixed parameter inertial control of the prior art under the same disturbance. It shows that the method does not cause over-control when the grid frequency fluctuates slightly, and can provide sufficient inertial support when the frequency fluctuates significantly, thus exhibiting good adaptability.

[0044] This application embodiment supports a dynamic adjustment mechanism for inertial parameters that adapts to disturbances: breaking through the traditional fixed parameter design, it divides disturbance levels based on the power grid frequency change rate and frequency deviation, matches the inertial support requirements of different intensities, and solves the problems of excessive micro-disturbances and insufficient strong disturbances.

[0045] The embodiments of this application have a deep coupling strategy of energy storage state and inertial control: the remaining charge and temperature of the battery are introduced as correction factors for the inertial parameters, so as to prioritize the safety of the battery during grid disturbances, avoid overcharging and over-discharging, and extend the battery cycle life. This application embodiment has a collaborative control logic for inertial support and AGC command frequency modulation component: the steady-state basic component and frequency modulation transient component are parsed from the AGC command issued by the power grid, and the frequency modulation transient component is superimposed with the VSG inertial support power to achieve functional decoupling of inertial response (transient) and AGC frequency modulation (steady-state), thereby improving the accuracy of power grid frequency regulation and reducing frequency fluctuation amplitude.

[0046] As a specific implementation of the aforementioned VSG-based adaptive inertial support control method for energy storage power stations, this application provides a VSG-based adaptive inertial support control device for energy storage power stations. Figure 4 As shown, the VSG-based adaptive inertial support control device 300 for energy storage power stations includes: The power grid status monitoring module 301 is used to collect power grid operating parameters, including power grid frequency and frequency change rate. The battery status management module 302 is used to monitor the status parameters of the energy storage battery pack, including the remaining power and battery temperature. VSG control module 303 includes a parameter optimization unit 3031, a rotor motion equation calculation unit 3032, and a power coordination unit 3033. The parameter optimization unit 3031 calculates the frequency deviation based on the grid frequency and the grid rated frequency, determines the grid disturbance level based on the frequency change rate and frequency deviation, determines the battery safety status based on the remaining charge and battery temperature, determines the disturbance adaptation coefficient based on the grid disturbance level, determines the battery status correction coefficient based on the battery safety status, and dynamically optimizes the VSG's inertial time constant and damping coefficient based on the disturbance adaptation coefficient and battery status correction coefficient. The rotor motion equation calculation unit 3032 calculates the basic inertial support power based on the inertial time constant and damping coefficient, combined with the VSG rotor motion equation. The power coordination unit 3033 coordinates the basic inertial support power with the frequency modulation component of the AGC command to obtain the final power command. PCS execution module 304 is used to send the final power command to the energy storage converter for execution.

[0047] The VSG-based adaptive inertial support control system 300 for energy storage power stations provided in this application embodiment can achieve... Figure 1 and Figure 2 The various processes implemented in the VSG-based adaptive inertial support control method for energy storage power stations will not be described in detail here to avoid repetition.

[0048] This application also provides a computer device, which includes a processor and a memory. The memory stores a program or instructions that can be run on the processor. When the program or instructions are executed by the processor, they implement the various steps of the above-described VSG-based adaptive inertial support control method for energy storage power stations and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0049] Memory can be used to store software programs and various data. Memory can primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area can store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, memory can include volatile memory or non-volatile memory, or both. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (Synchlink DRAM, SLDRAM), and direct memory bus RAM (DRRAM). The memory in the embodiments of this application includes, but is not limited to, these and any other suitable types of memory.

[0050] The processor may include one or more processing units; optionally, the processor integrates an application processor and a modem processor, wherein the application processor mainly handles operations related to the operating system, user interface, and applications, while the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into the processor.

[0051] This application also provides a readable storage medium storing a program or instructions. When the program or instructions are executed by a processor, they implement the various processes of the above-described VSG-based adaptive inertial support control method for energy storage power stations and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0052] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0053] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. An adaptive inertial support control method for a VSG-based energy storage power station, characterized in that, include: Collect grid operating parameters and energy storage battery pack status parameters. The grid operating parameters include grid frequency and frequency change rate, and the energy storage battery pack status parameters include remaining power and battery temperature. The frequency deviation is calculated based on the grid frequency and the grid rated frequency. The grid disturbance level is determined based on the frequency change rate and frequency deviation. The battery safety status is determined based on the remaining power and battery temperature. The disturbance adaptation coefficient is determined based on the grid disturbance level, the battery state correction coefficient is determined based on the battery safety status, and the inertial time constant and damping coefficient of the VSG are dynamically optimized based on the disturbance adaptation coefficient and the battery state correction coefficient. Based on the inertial time constant and damping coefficient, combined with the VSG rotor motion equation, the power of the foundation inertial support is calculated, and the power of the foundation inertial support is processed in conjunction with the frequency modulation component of the AGC command to obtain the final power command. The final power command is sent to the energy storage converter for execution.

2. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 1, characterized in that, The power grid disturbance levels are divided into three levels; The method of determining the power grid disturbance level based on the frequency change rate and frequency deviation includes: When the absolute value of the frequency change rate is less than or equal to the first change rate threshold and the frequency deviation is less than or equal to the first deviation threshold, the power grid disturbance level is determined to be a level one disturbance. When the absolute value of the frequency change rate is greater than the first change rate threshold and less than or equal to the second change rate threshold, and the frequency deviation is greater than the first deviation threshold and less than or equal to the second deviation threshold, the power grid disturbance level is determined to be a level two disturbance. When the absolute value of the rate of change of frequency is greater than the second rate of change threshold and the frequency deviation is greater than the second deviation threshold, the power grid disturbance level is determined to be a level three disturbance. Among them, the first rate of change threshold is less than the second rate of change threshold, and the first deviation threshold is less than the second deviation threshold.

3. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 1, characterized in that, The battery safety status is divided into three levels; The method of determining the battery safety status based on remaining power and battery temperature includes: When the remaining power is within the second power range and the battery temperature is within the first temperature range, the battery safety status is determined to be Level 1. When the remaining power is within the first or third power range and the battery temperature is within the first temperature range, the battery safety status is determined to be level two. When the remaining power is not within the first, second, or third power range, or the battery temperature is not within the first temperature range, the battery safety status is determined to be Level 3. The values ​​within the second power range are greater than those within the first power range and less than those within the third power range.

4. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 3, characterized in that, The process of determining the disturbance adaptation coefficient based on the grid disturbance level and the battery state correction coefficient based on the battery safety state includes: The disturbance adaptation coefficient is 0.5 to 0.8 for first-level disturbances, 1.0 to 1.2 for second-level disturbances, and 1.2 to 1.5 for third-level disturbances. The battery state correction coefficient is 1.0 for Level 1, 0.6 to 0.9 for Level 2, and 0 for Level 3.

5. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 1, characterized in that, The dynamic optimization of the VSG's inertial time constant and damping coefficient based on the perturbation adaptation coefficient and battery state correction coefficient includes: The inertial time constant J = J0 × k × m, the damping coefficient D = D0 × k × (2-m), J0 represents the reference inertial time constant, D0 represents the reference damping coefficient, k represents the disturbance adaptation coefficient, and m represents the battery state correction coefficient.

6. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 1, characterized in that, The step of co-processing the basic inertial support power with the frequency modulation component of the AGC command to obtain the final power command includes: The low-frequency and high-frequency components in the AGC command are separated by a low-pass filter, and the high-frequency components are superimposed on the basic inertial support power to obtain the inertial support power. The sum of the inertial support power and the low-frequency component is calculated as the final power command.

7. The adaptive inertial support control method for energy storage power stations based on VSG according to claim 1, characterized in that, After issuing the final power command to the energy storage converter for execution, the method further includes: The output power of the energy storage converter and the grid frequency feedback value are collected in real time, and the control error is calculated. When the control error and frequency deviation meet the preset conditions, the inertial time constant and damping coefficient are re-optimized.

8. An adaptive inertial support control system for a VSG-based energy storage power station, characterized in that, include: The power grid status monitoring module is used to collect power grid operating parameters, including power grid frequency and frequency change rate. The battery status management module is used to monitor the status parameters of the energy storage battery pack, including the remaining power and battery temperature. The VSG control module includes a parameter optimization unit, a rotor motion equation calculation unit, and a power coordination unit. The parameter optimization unit is used to calculate the frequency deviation based on the grid frequency and the grid rated frequency, determine the grid disturbance level based on the frequency change rate and frequency deviation, determine the battery safety status based on the remaining power and battery temperature, determine the disturbance adaptation coefficient based on the grid disturbance level, determine the battery status correction coefficient based on the battery safety status, and dynamically optimize the inertial time constant and damping coefficient of the VSG based on the disturbance adaptation coefficient and the battery status correction coefficient. The rotor motion equation calculation unit is used to calculate the power of the foundation inertial support based on the inertial time constant and damping coefficient, combined with the VSG rotor motion equation; the power coordination unit is used to coordinate the power of the foundation inertial support with the frequency modulation component of the AGC command to obtain the final power command. The PCS execution module is used to send the final power command to the energy storage converter for execution.

9. A computer device, characterized in that, It includes a processor and a memory, the memory storing a program or instructions that run on the processor, the program or instructions being executed by the processor to implement the steps of the VSG-based adaptive inertial support control method for energy storage power stations as described in any one of claims 1 to 7.

10. A readable storage medium storing a program or instructions, characterized in that, When the program or instructions are executed by the processor, they implement the steps of the adaptive inertial support control method for VSG-based energy storage power stations as described in any one of claims 1 to 7.

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