System short-circuit capacity estimation method and system considering voltage fluctuation quantity and reactive correction
By calculating the reactive power array and voltage fluctuation of the main power supply line in the power grid, the reactive power mutation point is identified and corrected, which solves the error problem of short-circuit capacity estimation in traditional methods and realizes higher accuracy short-circuit capacity measurement.
Patent Information
- Application Number
- CN202511650902.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-12
- Publication Date
- 2026-02-27
AI Technical Summary
In existing technologies, the voltage reactive power fluctuation method has a large deviation in short-circuit capacity estimation. In particular, it is easily affected by noise interference when the reactive power change is too small, and it is significantly underestimated when the reactive power change is too large, which affects the accuracy of the grid short-circuit capacity.
By calculating the total reactive power array of the power supply incoming line to the bus of interest, identifying reactive power abrupt changes, performing reactive power correction, and combining voltage fluctuations to calculate short-circuit capacity, the voltage and current signals are processed using Fourier transform to accurately measure the short-circuit capacity of the power grid.
It reduces calculation errors under high-power reactive power impacts, avoids the problem of short-circuit capacity calculation being easily affected by grid noise under small reactive power disturbances, and improves the accuracy of short-circuit capacity estimation.
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Figure CN121577958A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of power quality, in particular to a system short-circuit capacity estimation method and system considering voltage fluctuation and reactive power correction. BACKGROUND
[0002] In the operation of the power system, the short-circuit capacity refers to the product of the three-phase short-circuit current and the voltage before short-circuit when a three-phase short-circuit occurs at a power supply point. It can reflect the short-circuit current level, load carrying capacity and the strength of the connection between the power supply point and the power system. Therefore, it is not only the core basis for substation layout and equipment selection in power system planning and design, but also the key parameter for dispatching strategy optimization and fault risk prediction in operation mode development. It is also an important basis for evaluating the anti-disturbance ability of the power grid, the tolerance level of the equipment and the calculation of the power quality examination limit. The change of the operation mode of the power grid and the connection of the new energy to the power grid will affect the short-circuit capacity of the power grid. Therefore, it is of great practical significance to propose an accurate and efficient system short-circuit capacity estimation method to enhance the management and control of power quality.
[0003] Traditionally, the commonly used short-circuit capacity calculation methods mainly include simulation calculation method and estimation method using voltage and reactive power fluctuation. The simulation calculation method needs to obtain the key parameters of the power grid such as generators, transmission lines and power supply transformers. However, with the increasing proportion of distributed power sources such as wind power and photovoltaic power in the power system, the structure of the power grid tends to be complex and the operation mode is variable. Through simulation calculation of short-circuit capacity, not only the workload is huge, but also there will be a large calculation deviation due to inaccurate parameter acquisition. The national standard GB / T 12326-2008 "Power Quality - Voltage Fluctuation and Flicker" gives a short-circuit capacity estimation method based on voltage and reactive power fluctuation. However, this method also has a large estimation error in practical application. The main reasons are: when the reactive power variation is too small, it is easy to be disturbed by noise, resulting in a large random error in short-circuit capacity estimation; when the reactive power variation is too large, it will cause a large voltage drop, resulting in a significantly smaller short-circuit capacity estimation value. How to accurately measure the short-circuit capacity of the power grid through the operation data of the power grid is the main technical problem currently faced. SUMMARY
[0004] In view of the large deviation problem of the voltage and reactive power fluctuation method in the existing technology in the estimation of short-circuit capacity, the present application provides a system short-circuit capacity estimation method and system considering voltage fluctuation and reactive power correction, which can meet the demand for accurate calculation of the short-circuit capacity of the increasingly complex power system. The specific technical solutions are as follows: A system short-circuit capacity estimation method considering voltage fluctuation and reactive power correction, comprising the following steps: Step S1, calculating the reactive power array of the total incoming line of the power supply of the bus concerned; Step S2, identifying the reactive power mutation point corresponding to the maximum adjacent extreme point change in the monitored reactive power array to obtain the maximum reactive power value corresponding to the reactive power mutation point and the minimum reactive power value , and the maximum reactive power value and the minimum reactive power value corresponding to the fundamental wave voltage effective value of the concerned bus and ; Step S3, correcting the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point to obtain the corrected reactive power value under the nominal voltage; Step S4, calculating the voltage fluctuation amount according to the fundamental wave voltage effective value of the concerned bus and corresponding to the maximum reactive power value and the minimum reactive power value ; Step S5, calculating the short-circuit capacity based on the voltage fluctuation amount and the corrected reactive power value under the nominal voltage.
[0005] Preferably, the step S1 of calculating the reactive power array of the total incoming line of the power supply of the concerned bus specifically comprises the following steps: Step S11, collecting the three-phase voltage signal and the three-phase current signal of the concerned bus t at the moment; Step S12, performing Fourier transform on the three-phase voltage signal of the concerned bus t at the moment to obtain the three-phase fundamental wave voltage effective value and the three-phase fundamental wave voltage initial phase; Step S13, performing Fourier transform on the three-phase current signal of the concerned bus t at the moment to obtain the three-phase fundamental wave current effective value and the three-phase fundamental wave current initial phase; Step S14, calculating the three-phase total fundamental wave reactive power corresponding to the moment according to the three-phase fundamental wave voltage effective value and the three-phase fundamental wave voltage initial phase, the three-phase fundamental wave current effective value and the three-phase fundamental wave current initial phase, and further obtaining the reactive power array of the total incoming line of the power supply of the concerned bus. t
[0006] Preferably, the calculation method of the three-phase total fundamental wave reactive power in the step S14 is as follows: ; Wherein, k is the frequency domain array number after Fourier transform, and Q(k) is the kth three-phase total fundamental wave reactive power.
[0007] Preferably, the step S2 of identifying the corresponding reactive power mutation point with the largest change of adjacent extreme points in the monitored reactive power array comprises the following steps: In the monitored reactive power array, the extreme points of the reactive power array, including the maximum points and the minimum points, are identified, the reactive power difference values corresponding to the adjacent two maximum points and minimum points are calculated, and the two extreme points corresponding to the maximum reactive power difference value are selected as the corresponding reactive power mutation point.
[0008] Preferably, the corrected reactive power value under the nominal voltage in the step S3 comprises the maximum reactive power value under the corrected nominal voltage and the minimum reactive power value under the corrected nominal voltage, and the specific calculation method is as follows: ; ; In the formula, and are the maximum reactive power value under the corrected nominal voltage and the minimum reactive power value under the corrected nominal voltage respectively, is the nominal voltage value of the bus under attention.
[0009] Preferably, the calculation method of the voltage fluctuation amount in the step S4 is as follows: ; In the formula, is the voltage fluctuation amount, is the nominal voltage value of the bus under attention.
[0010] Preferably, the calculation method of the short-circuit capacity in the step S5 is as follows: ; In the formula, is the short-circuit capacity value of the bus under attention, and are the maximum reactive power value under the corrected nominal voltage and the minimum reactive power value under the corrected nominal voltage respectively, and d is the voltage fluctuation amount.
[0011] A system short-circuit capacity estimation system considering voltage fluctuation amount and reactive power correction, applying the method, comprising: A reactive power calculation module for calculating the reactive power array of the total incoming line of the power supply of the bus under attention; A mutation point identification module for identifying the corresponding reactive power mutation point with the largest change of adjacent extreme points in the monitored reactive power array, obtaining the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point, and the minimum reactive power value corresponding to the reactive power mutation point, and ; The reactive power correction module is used to adjust the maximum reactive power value corresponding to the reactive power abrupt change point. and minimum reactive power value Make corrections to obtain the corrected reactive power value under the nominal voltage. The voltage fluctuation calculation module is used to calculate the voltage fluctuation based on the maximum reactive power value. and minimum reactive power value The corresponding effective value of the fundamental voltage of the bus of interest and Calculate voltage fluctuation; The short-circuit capacity calculation module is used to calculate the short-circuit capacity based on the voltage fluctuation and the reactive power value under the corrected nominal voltage.
[0012] A computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device in which the computer-readable storage medium is located to perform the system short-circuit capacity estimation method that takes into account voltage fluctuations and reactive power correction.
[0013] A processor for running a program, wherein the program, when running, executes the system short-circuit capacity estimation method that takes into account voltage fluctuations and reactive power correction.
[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: Under high-power reactive power impact conditions, this invention uses nominal voltage to correct the measured reactive power fluctuation. Simulation results show that the calculation error of this invention is reduced compared with the traditional voltage reactive power fluctuation method. It solves the problem of significant calculation error of the traditional voltage reactive power fluctuation method under high-power reactive power impact, and also avoids the problem that the short-circuit capacity calculation is easily affected by grid noise under small reactive power disturbance. Attached Figure Description
[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.
[0016] Figure 1 This is a flowchart of the method of the present invention.
[0017] Figure 2 This is a schematic diagram of the measurement points used when estimating the short-circuit capacity of the busbar of interest.
[0018] Figure 3 This is a graph showing the trend of the fundamental voltage variation of the transformer's incoming line during testing.
[0019] Figure 4 The figure of the reactive power variation trend of the transformer incoming line for testing.
[0020] Figure 5 The figure of the reactive power variation trend and its extreme value distribution of the transformer incoming line for testing.
[0021] Figure 6 The system principle diagram of the present application. DETAILED DESCRIPTION
[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.
[0023] It should be understood that the terms "comprising" and "including" as used in the specification and the appended claims indicate the presence of the described features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.
[0024] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise.
[0025] It should be further understood that the term "and / or" as used in the present application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations thereof, and includes these combinations.
[0026] Embodiment 1: As shown in the figure, the present embodiment provides a system short circuit capacity estimation method considering voltage fluctuation and reactive power correction, including the following steps: Figure 1 Step S1, calculating the reactive power array of the total incoming line of the power supply of the concerned bus; specifically including the following steps: Step S11, collecting the three-phase voltage signal and the three-phase current signal of the concerned bus at the moment; wherein, The three-phase voltage signal at the moment is expressed as t , t , , , , tThe three-phase current signal at time t is represented as , , In the formula, a, b, and c are the phase sequence identifiers of the power supply, representing phase A, phase B, and phase C respectively, and t is the time marker for sampling the voltage and current signals. Generally, the sampling frequency of a power quality analyzer is 12.8kHz or 25.6kHz. t The interval is 78.125. μs Or 39.0625 μs .Right now , , They represent t The voltage signals of phases A, B, and C at time 10:00. , , They represent t The current signals of phase A, phase B, and phase C at time 1.
[0027] Step S12, for the bus of interest t The effective value of the three-phase fundamental voltage is obtained by performing a Fourier transform on the three-phase voltage signal at time t. , , and the initial phase of the three-phase fundamental voltage , , ;Right now , , These are the effective values of the fundamental voltages for phases A, B, and C, respectively. , , These are the initial phases of the fundamental voltages for phases A, B, and C, respectively.
[0028] Step S13, for the bus of interest t The effective value of the three-phase fundamental current is obtained by performing a Fourier transform on the three-phase current signal at time t. , , and the initial phase of the three-phase fundamental current , , ;Right now , , These are the effective values of the fundamental currents for phases A, B, and C, respectively. , , These are the initial phases of the fundamental currents in phases A, B, and C, respectively.
[0029] Step S14: Calculate the corresponding values based on the effective values and initial phases of the three-phase fundamental voltages, and the effective values and initial phases of the three-phase fundamental currents.t The three-phase total fundamental reactive power at the moment is calculated, and then the reactive power array of the total incoming line of the power supply of the bus under attention is obtained. The calculation method of the three-phase total fundamental reactive power is as follows: ; Wherein, Q(k) is the kth three-phase total fundamental reactive power, k is the number of the frequency domain fundamental array after Fourier transform, in order to highlight the change process of voltage and reactive power, the window length of Fourier transform is taken as 1 power frequency cycle, and the sliding window length is taken as 0.5 power frequency cycle, that is, the time interval of the reactive power array is 10ms.
[0030] In step S2, the maximum reactive power mutation point corresponding to the maximum change of adjacent extreme points in the monitored reactive power array is identified, and the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point are obtained. The fundamental voltage effective value and of the bus under attention corresponding to the maximum reactive power value and the minimum reactive power value
[0031] are obtained. In the monitored reactive power array, the extreme points of the reactive power array, including the maximum value points and the minimum value points, are identified, the reactive power difference values corresponding to adjacent two maximum value points and minimum value points are calculated, and the two extreme points corresponding to the maximum reactive power difference value are selected as the corresponding reactive power mutation point.
[0032] Let the kth reactive power data be The maximum value point is calculated as follows: and for all m=1,2, …, M. The minimum value point is calculated as follows: and for all m=1,2, …, M. In order to improve the robustness of the extreme point calculation, M can be taken as 3-5.
[0033] The found maximum value points and minimum value points are arranged in time sequence in turn to obtain the extreme point array The difference value of adjacent two extreme points is calculated to obtain wherein: wherein i=2,3, …, I. Wherein I is the array length of the extreme points.
[0034] The reactive power data with the maximum difference value of adjacent two extreme points is found, that is, , assuming that when i = p, the reactive power difference of the adjacent two extreme points is maximum, then the maximum reactive power corresponding to the maximum extreme point is , and the minimum reactive power is .
[0035] When the maximum and minimum reactive power values are obtained, the fundamental voltage values U1 and U2 corresponding to the maximum and minimum reactive power values are found, where , .
[0036] Step S3, the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point are corrected to obtain the corrected reactive power value under the nominal voltage.
[0037] The corrected reactive power value under the nominal voltage includes the corrected maximum reactive power value under the nominal voltage and the corrected minimum reactive power value under the nominal voltage, and the specific calculation method is as follows: ; ; In the formula, and are the corrected maximum reactive power value under the nominal voltage and the corrected minimum reactive power value under the nominal voltage, is the nominal voltage value of the concerned bus.
[0038] Step S4, according to the maximum reactive power value and the minimum reactive power value , the fundamental voltage effective value and of the concerned bus are calculated. The calculation method of the voltage fluctuation under the relative nominal voltage is as follows: ; Where d is the voltage fluctuation, is the nominal voltage value of the concerned bus.
[0039] Step S5, based on the voltage fluctuation and the corrected reactive power value under the nominal voltage, the short circuit capacity under the nominal voltage is calculated. The calculation method of the short circuit capacity under the nominal voltage is as follows: ; Where, is the short circuit capacity value of the concerned bus, and are the corrected maximum reactive power value under the nominal voltage and the corrected minimum reactive power value under the nominal voltage, and d is the voltage fluctuation.
[0040] To clearly demonstrate the technical features and significant advantages of this invention, a detailed description is provided below in conjunction with simulation scenarios.
[0041] Taking the short-circuit capacity calculation of the 35kV low-voltage busbar in a 220kV / 35kV substation as an example, the simulation model parameters are set as follows: the nominal voltage of the 220kV busbar is 220kV, the nominal frequency is 50Hz, and the short-circuit capacity is... Rated capacity of 2000MVA; 220kV / 35kV transformer It has a rated capacity of 250MVA, a rated voltage of 220kV on the high-voltage side, a rated voltage of 35kV on the low-voltage side, and a short-circuit impedance of [missing information]. It is 16%.
[0042] Based on the simulation parameters above, the theoretical value of the 35kV bus short-circuit capacity can be calculated. The calculation process is as follows: a) Calculate the fundamental impedance of the 35kV system: .
[0043] b) Calculate the short-circuit capacity of the 35kV system: .
[0044] Verification of 35kV bus short-circuit capacity test results. Monitoring data of the three-phase voltage of the 35kV bus and the current of the low-voltage main incoming line of the 220kV / 35kV transformer at this substation was performed. Figure 2 As shown, the sampling rate of the testing instrument is 128kHz. Fourier transform is used to calculate the amplitude and phase of the three-phase fundamental voltage and current. The window length of the Fourier transform is one power frequency cycle, and the sliding window length is 0.5 power frequency cycles. The calculated trends of the three-phase fundamental voltage and three-phase fundamental reactive power are shown below. Figure 3 and Figure 4 As shown. The calculated reactive power extreme points are respectively as follows: Figure 5 As shown, since the reactive power fluctuates over multiple periods during the monitoring period, there are multiple maximum and minimum points. Since the reactive power change is greatest between the maximum and minimum extreme points, the data showing the largest reactive power fluctuation between two adjacent extreme points is selected. The corresponding simulation data statistics are as follows: Table 1 Simulation Data Short-circuit capacity is calculated using the traditional voltage and reactive power fluctuation method. Specifically, the calculation steps include the following: Voltage fluctuation: ; Short-circuit capacity: .
[0045] The method of the embodiment is used to calculate the system short-circuit capacity , comprising: a corrected maximum reactive power value: ; a corrected minimum reactive power value: ; a corrected maximum reactive power fluctuation: ; a short-circuit capacity calculation value: .
[0046] The theoretical value of the short-circuit capacity of the 35kV bus calculated according to the simulation parameters is 877.19MVA, the short-circuit capacity value calculated by the traditional method is 732.08MVA, the calculation error is 16.54%, and the short-circuit capacity value calculated by the method of the embodiment is 848.93MVA, the calculation error is 3.22%. The main reason for the error generated by the method of the embodiment is that the influence of active power on voltage drop is not considered, but the short-circuit capacity error calculated under the same power grid condition is reduced by 80.53% compared with the traditional method.
[0047] Embodiment 2 As shown in Figure 6 , based on the same inventive concept as embodiment 1, the embodiment provides a system short-circuit capacity estimation system considering voltage fluctuation and reactive power correction, and the method comprises: a reactive power calculation module for calculating a reactive power array of the total incoming line of the power supply of the concerned bus; a mutation point identification module for identifying the corresponding reactive power mutation point with the largest adjacent extreme point change in the monitored reactive power array, obtaining the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point , and the fundamental wave voltage effective value and of the concerned bus corresponding to the maximum reactive power value and the minimum reactive power value ; a reactive power correction module for correcting the maximum reactive power value and the minimum reactive power value corresponding to the reactive power mutation point to obtain the reactive power value under the corrected nominal voltage; a voltage fluctuation calculation module for calculating the voltage fluctuation according to the fundamental wave voltage effective value and of the concerned bus corresponding to the maximum reactive power value and the minimum reactive power value The short-circuit capacity calculation module is configured to calculate the short-circuit capacity based on the voltage fluctuation amount and the reactive power value under the corrected nominal voltage.
[0048] Embodiment 3 Based on the same inventive concept as Embodiment 1, this embodiment provides a computer readable storage medium comprising a stored program, wherein the program, when executed, controls the device where the computer readable storage medium is located to perform the system short-circuit capacity estimation method considering voltage fluctuation amount and reactive power correction.
[0049] Embodiment 4 Based on the same inventive concept as Embodiment 1, this embodiment provides a processor configured to execute a program, wherein the program, when executed, performs the system short-circuit capacity estimation method considering voltage fluctuation amount and reactive power correction.
[0050] Those skilled in the art can understand that the modules of the examples described in combination with the embodiments disclosed herein can be realized in electronic hardware, computer software or a combination of both, and the components of the examples have been described in general in the above description in order to clearly illustrate the interchangeability of hardware and software. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.
[0051] In the embodiments provided by the present application, it should be understood that the division of modules is only a logical functional division, and actual implementation can have another division manner, for example, multiple modules can be combined into one module, one module can be split into multiple modules, or some features can be ignored, etc.
[0052] In addition, each functional module in each embodiment of the present application can be integrated into one processing module, or each module can exist physically independently, or two or more modules can be integrated into one module. The integrated module can be realized in the form of hardware or in the form of a software functional module.
[0053] The integrated module, if implemented in the form of a software function module and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or say the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.
[0054] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.
Claims
1. A method for estimating the short-circuit capacity of a system that takes into account voltage fluctuations and reactive power correction, characterized in that, Includes the following steps: Step S1: Calculate the reactive power array of the total incoming power supply to the bus of interest; Step S2: Identify the reactive power abrupt change point corresponding to the largest change among adjacent extreme points in the monitored reactive power array, and obtain the maximum reactive power value corresponding to the reactive power abrupt change point. and minimum reactive power value and maximum reactive power value and minimum reactive power value The corresponding effective value of the fundamental voltage of the bus of interest and ; Step S3: Calculate the maximum reactive power value corresponding to the reactive power abrupt change point. and minimum reactive power value Make corrections to obtain the corrected reactive power value under the nominal voltage. Step S4, based on the maximum reactive power value and minimum reactive power value The corresponding effective value of the fundamental voltage of the bus of interest and Calculate voltage fluctuation; Step S5: Calculate the short-circuit capacity based on the voltage fluctuation and the reactive power value under the corrected nominal voltage.
2. The method for estimating system short-circuit capacity considering voltage fluctuations and reactive power correction according to claim 1, characterized in that, Step S1, calculating the reactive power array of the total power input line to the bus of interest, specifically includes the following steps: Step S11, collect data on the bus of interest t The three-phase voltage signal and the three-phase current signal at each moment; Step S12, for the bus of interest t The effective value of the three-phase fundamental voltage and the initial phase of the three-phase fundamental voltage are obtained by performing a Fourier transform on the three-phase voltage signal at time t. Step S13, for the bus of interest t The effective value of the three-phase fundamental current and the initial phase of the three-phase fundamental current are obtained by performing a Fourier transform on the three-phase current signal at time t. Step S14: Calculate the corresponding values based on the effective values and initial phases of the three-phase fundamental voltages, and the effective values and initial phases of the three-phase fundamental currents. t The total fundamental reactive power of the three phases at a given time is used to obtain the reactive power array of the total incoming power supply to the bus of interest.
3. The method for estimating the short-circuit capacity of a system considering voltage fluctuations and reactive power correction as described in claim 1, characterized in that, The calculation method for the total fundamental reactive power of the three phases in step S14 is as follows: ； Where k is the frequency domain array number after Fourier transform, and Q(k) is the k-th three-phase total fundamental reactive power.
4. The method for estimating the short-circuit capacity of a system considering voltage fluctuations and reactive power correction according to claim 1, characterized in that, Step S2, identifying the reactive power abrupt change point corresponding to the largest change among adjacent extreme points in the monitored reactive power array, specifically includes the following steps: Identify the extreme points of the reactive power array in the monitored reactive power array, including maximum and minimum points. Calculate the reactive power difference between two adjacent maximum and minimum points. Select the two extreme points corresponding to the calculated maximum reactive power difference as the corresponding reactive power abrupt change points.
5. The method for estimating the short-circuit capacity of a system considering voltage fluctuations and reactive power correction according to claim 1, characterized in that, The corrected reactive power value under the nominal voltage in step S3 includes the maximum and minimum reactive power values under the corrected nominal voltage. The specific calculation method is as follows: ； ； In the formula, and These are the maximum and minimum reactive power values under the corrected nominal voltage, respectively. It focuses on the nominal voltage value of the busbar.
6. The method for estimating the short-circuit capacity of a system considering voltage fluctuations and reactive power correction according to claim 1, characterized in that, The voltage fluctuation in step S4 is calculated as follows: ； Where d is the voltage fluctuation. It focuses on the nominal voltage value of the busbar.
7. The method for estimating system short-circuit capacity considering voltage fluctuations and reactive power correction according to claim 1, characterized in that, The short-circuit capacity in step S5 is calculated as follows: ； in, To focus on the short-circuit capacity of the busbar, and These are the maximum and minimum reactive power values under the corrected nominal voltage, respectively, and d is the voltage fluctuation.
8. A system short-circuit capacity estimation system that takes into account voltage fluctuations and reactive power correction, characterized in that, The method described by any one of claims 1 to 7 includes: The reactive power calculation module is used to calculate the reactive power array of the main power supply line of the bus of interest; The mutation point identification module is used to identify the reactive power mutation point with the largest change among adjacent extreme points in the monitored reactive power array, and obtain the maximum reactive power value corresponding to the reactive power mutation point. and minimum reactive power value and maximum reactive power value and minimum reactive power value The corresponding effective value of the fundamental voltage of the bus of interest and ; The reactive power correction module is used to adjust the maximum reactive power value corresponding to the reactive power abrupt change point. and minimum reactive power value Make corrections to obtain the corrected reactive power value under the nominal voltage. The voltage fluctuation calculation module is used to calculate the voltage fluctuation based on the maximum reactive power value. and minimum reactive power value The corresponding effective value of the fundamental voltage of the bus of interest and Calculate voltage fluctuation; The short-circuit capacity calculation module is used to calculate the short-circuit capacity based on the voltage fluctuation and the reactive power value under the corrected nominal voltage.
9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the system short-circuit capacity estimation method taking into account voltage fluctuations and reactive power correction as described in any one of claims 1 to 7.
10. A processor, characterized in that, The processor is used to run a program, wherein the program executes the system short-circuit capacity estimation method that takes into account voltage fluctuations and reactive power correction as described in any one of claims 1 to 7.