Power grid defense adjustment method and system for coping with short-time power impact

Abstract

The invention discloses a power grid defense adjustment method and system for coping with short-time power impact, and relates to the technical field of power system automation control, and the method comprises the steps: obtaining new energy prediction information, calculating a new energy station output interval through the new energy prediction information, and setting a power grid frequency control requirement; constructing a power grid frequency response model, and outputting a frequency response time domain expression through the power grid frequency response model; dividing a new energy output curve according to the output interval of the new energy station, calculating a frequency prediction value based on the frequency response time domain expression, and determining an optimal new energy output value; and according to the optimal new energy output value, the defensive measure quantity is calculated and executed. The method provided by the invention can adapt to time variation of frequency characteristics caused by different short-time power impacts, reduces over-control or under-control risks of defense measures, and can effectively compensate time variation of temporary impacts.

Description

Technical Field

[0001] The present invention relates to the technical field of power system automation control, and in particular to a power grid defense adjustment method and system for coping with short-term power shocks. Background Art

[0002] The existing power grid defense system has obvious deficiencies in dealing with short-term power shocks. Traditional defense methods mainly rely on the frequency regulation capabilities of conventional generator sets, but these units have large mechanical inertia and slow response speed, making it difficult to effectively suppress instantaneous power shocks. Especially in the context of increasing penetration of new energy, the system inertia is reduced and the frequency change rate is accelerated, making the lag of traditional defense methods more prominent, which may result in the frequency deviation not being suppressed in time.

[0003] In addition, the existing defense system also faces challenges in terms of regulation accuracy and flexibility. The frequency regulation characteristics of conventional units are relatively fixed, and it is difficult to flexibly adjust their response characteristics according to different types and degrees of power shocks. At the same time, traditional load-side regulation methods (such as low-frequency load reduction) usually adopt fixed load shedding strategies and lack refined regulation capabilities. This lack of regulation accuracy and flexibility may lead to excessive or insufficient defense measures, affecting the economy and reliability of the power grid and failing to meet the increasingly complex power grid operation needs. Summary of the invention

[0004] In view of the fact that the existing power grid defense system has the problems of slow response speed, low adjustment accuracy and insufficient flexibility when dealing with short-term power shocks, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is how to deal with the short-term power impact of new energy, reduce the risk of system frequency exceeding the limit, and ensure the safety of system frequency.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In the first aspect, an embodiment of the present invention provides a power grid defense adjustment method for responding to short-term power shocks, which includes obtaining new energy prediction information, calculating the output range of new energy sites, and setting power grid frequency control requirements; constructing a power grid frequency response model, and outputting a frequency response time domain expression through the power grid frequency response model; dividing the new energy output curve according to the output range of the new energy site, calculating the frequency prediction value based on the frequency response time domain expression, and determining the optimal new energy output value; calculating the amount of defense measures according to the optimal new energy output value and executing them.

[0008] As a preferred solution of the power grid defense adjustment method for coping with short-term power shocks described in the present invention, the calculation formula of the output range of the new energy station is as follows:

[0009]

[0010] in, For the prediction of power of new energy, α BD To preset the confidence probability, is the upper and lower limits of the output range of the new energy station, δ BD is the data standard deviation, K BD is the uncertainty interval coefficient, and the specific formula is as follows:

[0011]

[0012] Among them, α BD The default confidence probability.

[0013] As a preferred solution of the power grid defense adjustment method for dealing with short-term power shocks described in the present invention, wherein: constructing a power grid frequency response model includes the following steps: obtaining the inertia time constant of conventional power grid generators; constructing a power transfer function for power grid frequency modulation and short-term power shocks; using the power transfer function to construct a frequency response transfer function after a power grid fault; constructing a permanent fault scenario based on the current power grid operation mode, and obtaining a system frequency response curve Δf(t); using numerical analysis tools, performing parameter fitting on the frequency response function according to the system frequency response curve Δf(t) data to determine the parameter value to be calculated; and combining the parameter value to be calculated and the output range of the new energy station and frequency control requirements are transmitted to the stabilization control system.

[0014] As a preferred solution of the power grid defense adjustment method for coping with short-term power shocks described in the present invention, the specific formula of the frequency response transfer function is as follows:

[0015]

[0016] Where Δf is the system frequency deviation, ΔP is the system disturbance, D is the system damping including generator damping and load frequency coefficient, K G is the frequency factor of the load, a0, a1, b0, K G is the parameter to be calculated, T J is the inertia time constant, is the real-time output information of the current new energy, and s is the variable after pull-type change.

[0017] As a preferred solution of the power grid defense adjustment method for coping with short-term power shocks described in the present invention, the specific formula of the power transfer function is as follows:

[0018]

[0019] Among them, P tis the unbalanced power caused by grid frequency regulation and short-term power shock, Δf is the system frequency deviation, a0, a1, b0, K G is the parameter value to be calculated, Real-time output information of current new energy sources, Forecast power for new energy, i e N is the number of the new energy station. e is the total number of new energy stations.

[0020] As a preferred solution of the power grid defense adjustment method for dealing with short-term power shocks described in the present invention, determining the optimal new energy output value includes the following steps: obtaining fault information and unbalanced power; according to the output range of the new energy station Determine the number of divisions, division M q A new energy output curve is obtained; according to the time domain expression of the fault frequency response, the frequency prediction value and the prediction deviation are calculated; according to the prediction deviation, the optimal new energy output value is determined; the specific formula of the prediction deviation is as follows:

[0021]

[0022] Where Δf di (t it ) is the predicted value, Δf(t it ) is the actual value, t it Number the time interval.

[0023] As a preferred solution of the power grid defense adjustment method for dealing with short-term power shocks described in the present invention, wherein: the defense measure amount is calculated according to the optimal new energy output value and executed, including setting the emergency system defense measure amount C p Based on the defensive measures C p The time domain expression of the fault frequency response is modified; the frequency deviation value is calculated using the modified time domain expression of the fault frequency response; it is determined whether the frequency deviation value satisfies the system frequency stability constraint. If it does not satisfy the system frequency stability constraint, the defense measure quantity optimization process is executed to obtain the optimal defense measure quantity; the optimal defense measure quantity is sent to the emergency control system to perform corresponding power adjustment.

[0024] In the second aspect, an embodiment of the present invention provides a power grid defense adjustment system for responding to short-term power shocks, which includes a new energy information processing module for obtaining new energy prediction information, calculating the output range of new energy sites, and setting power grid frequency control requirements; a frequency response modeling module for constructing a power grid frequency response model, and outputting a frequency response time domain expression through the power grid frequency response model; a new energy output optimization module for dividing the new energy output curve according to the output range of the new energy site, calculating the frequency prediction value based on the frequency response time domain expression, and determining the optimal new energy output value; a defense measure execution module for calculating and executing the defense measure amount according to the optimal new energy output value.

[0025] In a third aspect, an embodiment of the present invention provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: when the computer program instructions are executed by the processor, the steps of the power grid defense adjustment method for responding to short-term power shocks as described in the first aspect of the present invention are implemented.

[0026] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program instructions are executed by a processor, the steps of the power grid defense adjustment method for responding to short-term power shocks as described in the first aspect of the present invention are implemented.

[0027] The beneficial effects of the present invention are as follows: the present invention acquires the prediction information of new energy in real time and calculates the output range, constructs an accurate power grid frequency response model, and realizes accurate grasp of the volatility of new energy. The method determines the optimal new energy output value based on the frequency response time domain expression, and adopts a closed-loop iteration strategy to dynamically optimize the amount of defense measures, which not only considers the impact of new energy output fluctuations, but also adjusts the defense strategy according to the real-time frequency response situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 Flowchart of a grid defense adjustment method for short-term power surges.

[0030] Figure 2 Schematic diagram of the grid defense adjustment method to cope with short-term power surges.

[0031] Figure 3The grid frequency response curve of the new energy power generation after the Jinsu DC dual-machine locking at 5%, 10%, and 15% for the grid defense adjustment method to cope with short-term power shocks.

[0032] Figure 4 The system frequency curve after a short-term power shock of the power grid defense adjustment method for coping with the short-term power shock.

[0033] Figure 5 The invention discloses a frequency curve of a power grid defense adjustment method for coping with short-term power shocks.

[0034] Figure 6 Computer equipment diagram of a method for adjusting the defense of a power grid to cope with short-term power surges. DETAILED DESCRIPTION

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0037] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0038] Example 1

[0039] Reference Figure 1 to Figure 6 , which is the first embodiment of the present invention, and provides a method for adjusting the power grid defense against short-term power shocks. The flow chart is as follows Figure 1 As shown in the schematic diagram Figure 2 As shown, including

[0040] S1: Obtain new energy forecast information, calculate the output range of new energy stations based on the new energy forecast information, and set power grid frequency control requirements.

[0041] Specifically, the following steps are included:

[0042] S1.1: Obtain real-time forecast information of new energy stations in the power grid.

[0043] Specifically, the real-time prediction information includes the predicted new energy power of the new energy stations.

[0044] S1.2: Obtain historical prediction information of new energy stations and their corresponding actual output information.

[0045] S1.3: Based on the preset signal probability and the predicted power of the new energy, the output range of the new energy station is calculated.

[0046] Optimized output range of new energy stations The calculation method is as follows:

[0047]

[0048] in, For the prediction of power of new energy, α BD To preset the confidence probability, K is the upper and lower limits of the output range of the new energy station, BD is the uncertainty interval coefficient, δ BD is the data standard deviation, and the specific formula is as follows:

[0049]

[0050] Among them, α BD To preset the confidence probability, For new energy stations e The actual output information, For new energy stations e Historical forecast information, N e is the total number of new energy stations, N h is the number of historical actual output information, i e is the number of the new energy station, μ y is the expected value of the new energy power prediction error.

[0051] It should be noted that α BD Determined according to the robust control requirements, the value is generally between 0.95-0.99.

[0052] Preferably, the calculation method effectively improves the accuracy and reliability of renewable energy output forecasting by introducing preset confidence probabilities and uncertainty interval coefficients. It fully considers the randomness and volatility of renewable energy power generation, and uses historical actual output and forecast data for statistical analysis to derive an output range that is closer to the actual situation. The flexibility of the method is reflected in allowing dispatchers to adjust the credibility level according to demand and balance forecast accuracy and system stability. By calculating the standard deviation and the expected value of the forecast error, the method effectively characterizes the uncertainty of renewable energy power generation and provides quantitative indicators for risk assessment. This easy-to-implement and understand probabilistic statistical method can be seamlessly integrated into the existing power dispatching system to improve the overall dispatching efficiency. The upper and lower limits of the output provide a clear reference for the operation of the power grid, which helps to formulate a more reasonable dispatching plan and improve the economy and safety of the system.

[0053] S1.4: Offline setting of grid frequency control requirements after a fault.

[0054] Specifically, the frequency control requirements include the maximum frequency deviation Δf zmax and the maximum steady-state frequency deviation Δf wmax .

[0055] S2: constructing a power grid frequency response model, and outputting a frequency response time domain expression through the power grid frequency response model.

[0056] Specifically, the following steps are included:

[0057] S2.1: Obtain the inertia time constant of the conventional generator of the power grid.

[0058] Specifically, the inertia time constant T J The specific formula is as follows:

[0059]

[0060] Among them, i c N is the number of the conventional generator. c is the total number of conventional generators, H c For conventional generator c The rotor inertia (obtained through the generator parameters), ω m For conventional generator c The mechanical angular velocity, ω mc For conventional generators c The mechanical angular acceleration.

[0061] S2.2: Construct the power transfer function for grid frequency regulation and short-term power surges.

[0062] Specifically, the specific formula of the power transfer function is as follows:

[0063]

[0064] Among them, P t is the unbalanced power caused by grid frequency regulation and short-term power shock, Δf is the system frequency deviation, a0, a1, b0, K G is the parameter value to be calculated, Real-time output information of current new energy sources, Forecast power for new energy, i e N is the number of the new energy station. e is the total number of new energy stations.

[0065] S2.3: Use the power transfer function to construct a frequency response transfer function after a power grid fault.

[0066] Specifically, the specific formula of the frequency response transfer function is as follows:

[0067]

[0068] Where Δf is the system frequency deviation, ΔP is the system disturbance, D is the system damping including generator damping and load frequency coefficient, K g is the frequency factor of the load, a0, a1, b0, K G is the parameter to be calculated, T J is the inertia time constant, It provides real-time output information of current new energy sources.

[0069] Furthermore, the Laplace inverse transform is used to derive the time domain expression of the fault frequency response corresponding to the frequency response function. The specific formula is as follows:

[0070]

[0071] Where Δf yc is the predicted frequency curve, ΔP is the system disturbance power, C, C1, C2, C3 are intermediate calculation constants, K g is the frequency factor of the load, t is the time, is the real-time output information of the current new energy, a0, a1, b0, K G is the parameter value to be calculated, T J is the inertia time constant, and D is the system damping including generator damping and load frequency coefficient.

[0072] S2.4: Construct a permanent fault scenario based on the current grid operation mode and obtain the system frequency response curve Δf(t).

[0073] It should be noted that the power loss due to a fault is ΔP.

[0074] S2.5: Using numerical analysis tools (MATLAB toolbox), perform parameter fitting on the frequency response function according to the system frequency response curve Δf(t) data to determine the parameter values ​​to be calculated.

[0075] S2.6: Set the parameter value to be calculated and the output range of the new energy station and frequency control requirements are transmitted to the stabilization control system.

[0076] It should be noted that the parameter values ​​to be calculated include a0, a1, b0, K G , D, frequency control requirements include the maximum frequency deviation Δf zmax and the maximum steady-state frequency deviation Δf wmax .

[0077] Preferably, the construction method of the power grid frequency response model effectively captures the dynamic characteristics and frequency response behavior of the power grid through systematic steps. From obtaining the generator inertia time constant to constructing the power transfer function, to deriving the frequency response time domain expression, and finally performing parameter fitting through numerical analysis, this series of processes comprehensively considers factors such as conventional power generation, new energy impact and system disturbance. The significant advantage of this method is that it can accurately simulate the frequency response of the power grid under various operating conditions and fault conditions, providing a reliable theoretical basis and decision-making basis for power grid dispatching and stability control. By transmitting the calculation results to the stability control system, the seamless connection between theoretical analysis and practical application is achieved, which helps to improve the overall stability and reliability of the power grid, especially in the context of large-scale access to new energy, and provides strong support for the safe and economical operation of the power system.

[0078] S3: Divide the new energy output curve according to the output range of the new energy station, calculate the frequency prediction value based on the frequency response time domain expression, and determine the optimal new energy output value.

[0079] Specifically, the following steps are included:

[0080] S3.1: Obtain fault information and unbalanced power.

[0081] Specifically, the stabilization control system obtains the frequency deviation information of the power grid in real time for 300ms according to the fault trigger signal, and obtains a frequency deviation value every 1ms, which are Δf(t it ). Where t it The permanent unbalanced power ΔP caused by the fault is obtained. er .

[0082] S3.2: Based on the output range of new energy stations Determine the number of divisions, division M q New energy output curve.

[0083] It should be noted that new energy output The specific formula is as follows:

[0084]

[0085] in, is the upper and lower limits of the output range of the new energy station, i di M q The number of the new energy output curve, i di =1,2..M q .

[0086] It should be noted that M q It is determined according to the output range of new energy, and generally takes a value between 50-100.

[0087] S3.3: Calculate the frequency prediction value and prediction deviation based on the time domain expression of the fault frequency response.

[0088] Specifically, the prediction deviation is calculated by calculating the predicted value Δf 300ms before the frequency di (t it ) and the actual value Δf(t it )'s second-order norm ||Α di ||2, the specific formula is as follows:

[0089]

[0090] Where Δf di (t it ) is the predicted value, Δf(t it ) is the actual value, t it Number the time interval.

[0091] S3.4: Determine the optimal new energy output value.

[0092] Specifically, compare M q The prediction deviations corresponding to the new energy output curves are calculated, and the new energy output curve with the smallest prediction deviation is selected to determine the corresponding new energy output value as the optimal new energy output value.

[0093] Furthermore, based on the optimal new energy output value, the second frequency curve Δf is predicted using the fault frequency response time domain expression. yc (t w +0.3)(after 300ms of the power grid), where t w is the predicted time, t w =0,0.01,0.02...25.

[0094] Preferably, this method effectively optimizes the output control of renewable energy in the power grid through refined analysis and prediction. First, by obtaining fault information and unbalanced power in real time, accurate initial conditions are provided for subsequent analysis. Then, the output curve is flexibly divided according to the output range of the renewable energy station, fully considering the adjustable range of renewable energy output. By combining these output curves with the time-domain expression of the frequency response, a series of frequency prediction values ​​and prediction deviations are calculated, realizing a comprehensive simulation of the frequency response of the power grid under different output conditions. Finally, by comparing the prediction deviations and selecting the optimal renewable energy output value, it is possible to not only minimize the frequency deviation to the greatest extent, but also predict the frequency change trend in the future. The advantage of this method is that it can respond quickly when a fault occurs in the power grid, reduce the impact of the fault by optimizing the output of renewable energy, and improve the stability of the system.

[0095] S4: Calculate and execute the amount of defense measures according to the optimal new energy output value.

[0096] Specifically, the following steps are included:

[0097] S4.1: Set emergency system defense measures C p .

[0098] It should be noted that the first emergency system defense measure can be set to 50MW.

[0099] S4.2: Modify the time domain expression of the fault frequency response based on the defensive measure quantity.

[0100] Specifically, the emergency system defense measure C p Incorporating this into the time domain expression of the fault frequency response, the modified time domain expression of the fault frequency response is Δf yc =(ΔP-C p )C, where ΔP is the system disturbance and C is a constant.

[0101] S4.3: Using the modified time domain expression of the fault frequency response, calculate the frequency deviation value.

[0102] It should be noted that the frequency deviation value includes the maximum transient frequency deviation value Δf yc_zmax (t w +0.3) and the maximum steady-state frequency deviation Δf yc_wmax (t w +0.3), the specific formula is as follows:

[0103] Δf yc_zmax (t w +0.3)=max{Δf yc (t w +0.3),t w ∈[0,25]}

[0104] Δf yc_wmax (t w +0.3)=max{Δf yc (t w +0.3),t w ∈[10,25]}

[0105] Where Δf yc (t w +0.3) is the second frequency curve.

[0106] S4.4: Determine whether the frequency deviation value satisfies the system frequency stability constraint.

[0107] It should be noted that the specific formula for the system frequency stability constraint is as follows:

[0108]

[0109] Where Δf yc_zmax (t w +0.3) is the maximum transient frequency deviation value, Δf yc_wmax (t w +0.3) is the maximum steady-state frequency deviation, Δf zmax is the maximum allowable deviation of transient frequency, Δf wmax It is the maximum allowable value of steady-state frequency deviation, which is determined by the power system operation regulations.

[0110] S4.5: If the system frequency stability constraint is not met, the defense measure quantity optimization process is executed to obtain the optimal defense measure quantity.

[0111] Specifically, the defense measure quantity optimization process includes: updating the defense measure quantity to C p =C p +ΔP step , use the updated defense measure quantity to recalculate the frequency response and constraint judgment, and repeat the above process until the optimal defense measure quantity that meets the system frequency stability constraint is found.

[0112] It should be noted that ΔP step The value range is 20-80MW.

[0113] S4.6: Send the optimal defense measure quantity to the emergency control system and perform corresponding power adjustment.

[0114] Preferably, the method achieves precise control and optimization of grid frequency stability through systematic steps. First, the initial defense measure quantity is set as the benchmark, and then a more accurate simulation of the system response is achieved by incorporating it into the modified frequency response time domain expression. By calculating the maximum transient and steady-state frequency deviations and comparing them with the system stability constraints, the method can accurately evaluate the effectiveness of the current defense measures. If the constraints are not met, the defense measure quantity is dynamically adjusted through an iterative optimization process until the optimal solution is found. This closed-loop iterative strategy can not only adapt to complex and changeable grid conditions, but also minimize intervention measures while ensuring system stability. Especially when considering the impact of fluctuations in renewable energy output, the method shows excellent adaptability and robustness. By sending the optimal defense measure quantity to the emergency control system and performing corresponding power regulation, a seamless connection between theoretical analysis and practical operation is achieved.

[0115] Furthermore, the present embodiment also provides a power grid defense adjustment system for responding to short-term power shocks, including a new energy information processing module, which is used to obtain new energy prediction information, calculate the output range of new energy sites, and set power grid frequency control requirements; a frequency response modeling module, which is used to construct a power grid frequency response model, and output a frequency response time domain expression through the power grid frequency response model; a new energy output optimization module, which is used to divide the new energy output curve according to the output range of the new energy site, calculate the frequency prediction value based on the frequency response time domain expression, and determine the optimal new energy output value; a defense measure execution module, which is used to calculate and execute the defense measure amount according to the optimal new energy output value.

[0116] This embodiment also provides a computer device, which is applicable to the case of a power grid defense adjustment method for dealing with short-term power shocks, and includes a memory and a processor; the memory is used to store computer executable instructions, and the processor is used to execute the computer executable instructions to implement the power grid defense adjustment method for dealing with short-term power shocks proposed in the above embodiment. Figure 6 shown.

[0117] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, an operator network, NFC (near field communication) or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or a key, trackball or touchpad provided on the housing of the computer device, or an external keyboard, touchpad or mouse, etc.

[0118] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method for adjusting the power grid defense against short-term power shocks proposed in the above embodiment is implemented.

[0119] In summary, the present invention acquires new energy prediction information in real time and calculates the output range to construct an accurate power grid frequency response model, thereby achieving an accurate grasp of the volatility of new energy. This method determines the optimal new energy output value based on the frequency response time domain expression, and uses a closed-loop iterative strategy to dynamically optimize the amount of defense measures. It not only considers the impact of new energy output fluctuations, but also adjusts the defense strategy according to the real-time frequency response. The method proposed in the present invention can adapt to the time-varying frequency characteristics caused by different short-term power shocks, reduces the risk of over-control or under-control of the defense measures, and can effectively compensate for the time-varying nature of temporary shocks.

[0120] Example 2

[0121] Reference Figure 1 to Figure 6 , which is the second embodiment of the present invention, provides a dual-arm robot dynamic task adjustment method based on machine learning. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0122] Specifically, the calculation is based on the operation mode of the East China Power Grid in 2023, with the new energy scale accounting for 73% and thermal power accounting for 19%. The frequency response curve of the power grid after the Jinsu DC dual-machine interlocking is calculated at 5%, 10%, and 15% of new energy generation, as shown in the figure below: Figure 3 shown.

[0123] Furthermore, according to the frequency response curve, the parameters a0, a1, b0, K G The estimated values ​​are shown in Table 1.

[0124] Table 1a0, a1, b0, K G Estimated value of

[0125] parameter <![CDATA[a0]]> <![CDATA[a1]]> <![CDATA[b0]]> <![CDATA[K G ]]> Estimated value 144.45 212.49 53.43 1.5

[0126] Furthermore, after the 1000kV Anji-Lanjiang Sanyong N-1 fault in East China was simulated, a large amount of renewable energy entered the low-voltage circuit and provided a large amount of short-term power impact. The system frequency curve is as follows: Figure 4 As shown. Using the defense method proposed by this method, the system frequency response is as follows Figure 5 As shown, the horizontal axis of the system is time, and the vertical axis is the per-unit value of the system frequency deviation. It can be seen that the frequency stability characteristics of the system are greatly improved.

[0127] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A power grid defense adjustment method for coping with short-term power shocks, characterized in that: include, Obtain new energy forecast information, calculate the output range of new energy stations, and set grid frequency control requirements; Constructing a power grid frequency response model, and outputting a frequency response time domain expression through the power grid frequency response model; Divide the new energy output curve according to the output range of the new energy station, calculate the frequency prediction value based on the frequency response time domain expression, and determine the optimal new energy output value; The amount of defensive measures is calculated and executed according to the optimal new energy output value.

2. The method for adjusting the power grid defense against short-term power shocks according to claim 1, characterized in that: The calculation formula for the output range of the new energy station is as follows: in, For the predicted power of new energy, α BD To preset the confidence probability, is the upper and lower limits of the output range of the new energy station, δ BD is the data standard deviation, K BD is the uncertainty interval coefficient, and the specific formula is as follows: Among them, α BD The default confidence probability.

3. The method for adjusting the power grid defense against short-term power shocks according to claim 2, characterized in that: The construction of the power grid frequency response model comprises the following steps: Obtain the inertia time constant of conventional generators in the power grid; Construct power transfer functions for grid frequency regulation and short-term power surges; constructing a frequency response transfer function after a power grid fault using the power transfer function; Construct a permanent fault scenario based on the current grid operation mode and obtain the system frequency response curve Δf(t); Using numerical analysis tools, the frequency response function is parameter-fitted according to the system frequency response curve Δf(t) data to determine the parameter values ​​to be calculated; The parameter values ​​to be calculated and the output range of the new energy station and frequency control requirements are transmitted to the stabilization control system.

4. The method for adjusting the power grid defense against short-term power shocks according to claim 3, characterized in that: The specific formula of the frequency response transfer function is as follows: Where Δf is the system frequency deviation, ΔP is the system disturbance, D is the system damping including generator damping and load frequency coefficient, K G is the frequency factor of the load, a0, a1, b0, K G is the parameter to be calculated, T J is the inertia time constant, It provides real-time output information of current new energy sources.

5. The method for adjusting the power grid defense against short-term power shocks according to claim 3, characterized in that: The specific formula of the power transfer function is as follows: Among them, P t is the unbalanced power caused by grid frequency regulation and short-term power shock, Δf is the system frequency deviation, a0, a1, b0, K G is the parameter value to be calculated, Real-time output information of current new energy sources, Forecast power for new energy, i e N is the number of the new energy station. e is the total number of new energy stations.

6. The method for adjusting the power grid defense against short-term power shocks according to claim 1, characterized in that: Determining the optimal new energy output value comprises the following steps: Obtain fault information and unbalanced power; According to the output range of new energy stations Determine the number of divisions, division M q New energy output curve; According to the time domain expression of fault frequency response, the frequency prediction value and prediction deviation are calculated; Determining the optimal new energy output value according to the prediction deviation; The specific formula of the prediction deviation is as follows: Where Δf di (t it ) is the predicted value, Δf(t it ) is the actual value, t it Number the time interval.

7. The method for adjusting the power grid defense against short-term power shocks according to claim 1, characterized in that: The calculation and execution of the defensive measures according to the optimal new energy output value includes: Set up emergency system defense measures C p ; Based on the defensive measure quantity C p Modify the time domain expression of fault frequency response; Calculate the frequency deviation value using the modified time domain expression of the fault frequency response; Determine whether the frequency deviation value satisfies the system frequency stability constraint. If it does not satisfy the system frequency stability constraint, execute the defense measure quantity optimization process to obtain the optimal defense measure quantity. The optimal defense measures are sent to the emergency control system to perform corresponding power adjustments.

8. A power grid defense adjustment system for coping with short-term power shocks, based on the power grid defense adjustment method for coping with short-term power shocks according to any one of claims 1 to 7, characterized in that: Also includes, New energy information processing module, used to obtain new energy forecast information, calculate the output range of new energy stations, and set grid frequency control requirements; A frequency response modeling module is used to construct a power grid frequency response model and output a frequency response time domain expression through the power grid frequency response model; A new energy output optimization module, used to divide the new energy output curve according to the output range of the new energy station, calculate the frequency prediction value based on the frequency response time domain expression, and determine the optimal new energy output value; The defense measure execution module is used to calculate and execute the defense measure amount according to the optimal new energy output value.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the power grid defense adjustment method for coping with short-term power shocks described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power grid defense adjustment method for coping with short-term power shocks described in any one of claims 1 to 7 are implemented.

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