A system stability verification method and system based on a parallel process of a partitioned power grid

Abstract

The application discloses a kind of based on partition power grid parallel process system stability verification method and system, method includes: obtaining power grid topology and line parameter, network partition is carried out using GN splitting algorithm and the closeness of partition is evaluated;Select the reasonable partition scheme of closeness, establish the objective function with the optimization target of unit active output and load recovery amount and solve, obtain optimal parallel scheme;With the scheme as initial state, the method combining Newton-Raphson method and potential energy boundary method is used, the voltage, frequency dynamic oscillation process of system under N-1 / N-2 fault is iteratively simulated and analyzed;Based on oscillation level, unit inertia and load recovery rate, calculate the partition power grid parallel stability coefficient, determine system stability grade according to coefficient value.The application realizes the whole process quantitative evaluation from partition optimization, operation decision to dynamic simulation, significantly improves the accuracy and decision efficiency of stability verification before parallel operation.

Description

Technical Field

[0001] This invention belongs to the field of power system stability analysis technology, and in particular relates to a system stability verification method and system based on the parallel process of regional power grids. Background Technology

[0002] As the scale of the power grid expands and the degree of interconnection deepens, parallel operation of regional power grids is often required during system recovery after a fault or during planned operations. This process involves drastic changes in power balance, voltage, and frequency. If not properly controlled, it can easily lead to system instability, or even cause parallel operation failure or expand the scope of the accident.

[0003] Traditional methods for assessing grid parallel stability often rely on dispatcher experience, fixed operating procedures, or static safety analysis. These methods have the following shortcomings: First, they lack refined quantitative analysis of the dynamic partitioning of the grid topology and the tightness of its internal electrical connections; second, they do not adequately consider the coordinated optimization of unit output and load recovery during parallel operation; third, they are difficult to accurately predict and quantify the dynamic voltage and frequency oscillation risks that may occur in the system under typical fault scenarios such as N-1 or N-2; and fourth, the assessment process is relatively lagging, failing to provide rapid and quantitative stability criteria for real-time decision-making.

[0004] Therefore, there is an urgent need to develop a method that can integrate network partitioning optimization, operation mode decision-making, dynamic process simulation and stability quantitative assessment to improve the reliability, safety and decision-making efficiency of the paralleling process of regional power grids. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of existing technologies and provide a system and method for verifying system stability based on the parallel operation process of a zoned power grid. This method achieves rapid and accurate prediction and verification of the stability of the parallel operation process by quantifying the degree of zone tightness, optimizing the parallel operation mode, simulating and analyzing fault dynamics, and calculating the comprehensive stability coefficient.

[0006] In a first aspect, the present invention provides a system stability verification method based on the paralleling process of a regional power grid, comprising:

[0007] Obtain the topology and line parameters of the target power grid. Based on the topology and line reactance parameters, use the GN splitting algorithm to divide the network, obtain at least one partitioning scheme, and calculate the density value of at least one partitioning scheme.

[0008] Among the at least one partitioning scheme, a target partitioning scheme with a density value within a preset range is selected. Based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, a parallel objective function for the partitioned power grid is established with the active power output of the units and the load recovery amount as optimization variables.

[0009] Solve the objective function of the parallel regional power grid to obtain the optimal unit start-up combination and load recovery sequence;

[0010] Using the optimal unit start-up combination and load recovery sequence as the initial operating state, a preset iterative method is used to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state.

[0011] Based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, the parallel stability coefficient of the regional power grid is calculated, and the stability level of the system during the parallel connection process of the regional power grid is determined and output according to the numerical range of the parallel stability coefficient of the regional power grid.

[0012] Secondly, the present invention provides a system stability verification system based on the paralleling process of a regional power grid, comprising:

[0013] The partitioning module is configured to acquire the topology and line parameters of the target power grid, and based on the topology and line reactance parameters, perform network partitioning using the GN splitting algorithm to obtain at least one partitioning scheme and calculate the compactness value of at least one partitioning scheme.

[0014] The module is configured to select a target partitioning scheme with a density value within a preset range from the at least one partitioning scheme, and based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, establish a parallel objective function for the partitioned power grid with the active power output of the units and the load recovery amount as optimization variables.

[0015] The solution module is configured to solve the parallel objective function of the regional power grid to obtain the optimal unit start-up combination and load recovery sequence;

[0016] The simulation module is configured to use the optimal unit start-up combination and load recovery sequence as the initial operating state, and to use a preset iterative method to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state.

[0017] The calculation module is configured to calculate the parallel stability coefficient of the regional power grid based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, and determine and output the stability level of the system during the parallel connection process of the regional power grid according to the numerical range of the parallel stability coefficient of the regional power grid.

[0018] Thirdly, an electronic device is provided, comprising: at least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the steps of the system stability verification method based on the parallel process of a partitioned power grid according to any embodiment of the present invention.

[0019] Fourthly, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor performs the steps of the system stability verification method based on the parallel process of a partitioned power grid according to any embodiment of the present invention.

[0020] This application presents a system stability verification method and system based on the parallel operation of a regional power grid. It employs the GN splitting algorithm to measure the decision domain of each regional control node in the power grid, establishes a regional power grid parallel objective function that couples the active power output and load recovery of generating units, and uses the Newton-Raphson method and PEBS principle to iteratively analyze the voltage and frequency oscillations during the regional power grid parallel operation. It also flexibly adjusts the frequency recovery priority and voltage suppression coefficient, outputting a parallel stability coefficient. This approach improves the accuracy of decisions previously made solely based on historical experience and initial human judgment, expands the rationalization of various stability indicators under multiple scenarios of regional power grid parallel operation, enhances the decision-making efficiency of the dispatch control center in judging system stability during the regional power grid parallel operation, and ensures the safe and stable operation of the system during the parallel operation of the regional power grid. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A flowchart illustrating a system stability verification method based on the paralleling process of a partitioned power grid, provided in an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of the parallel connection process of a zoned power grid area is provided for a specific embodiment of the present invention;

[0024] Figure 3 A specific embodiment of the present invention provides a fluctuation diagram of the parallel frequency curve of a regional power grid;

[0025] Figure 4 A voltage fluctuation curve diagram of parallel stations in a zoned power grid is provided as a specific embodiment of the present invention;

[0026] Figure 5 A structural block diagram of a system stability verification system based on the parallel process of a partitioned power grid, provided in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Please see Figure 1 The diagram shows a flowchart of a system stability verification method based on the parallel process of a partitioned power grid according to this application.

[0030] like Figure 1 As shown, the system stability verification method based on the paralleling process of regional power grids specifically includes the following steps:

[0031] Step S101: Obtain the topology and line parameters of the target power grid. Based on the topology and line reactance parameters, use the GN splitting algorithm to divide the network, obtain at least one partitioning scheme, and calculate the density value of at least one partitioning scheme.

[0032] In this step, the expression for calculating the tightness value of at least one partitioning scheme is:

[0033] ,

[0034] In the formula, To measure the tightness of regional power grid partitioning using the GN splitting algorithm, and For nodes With nodes The edge weights of the line reactance between them. The total number of sides of the power grid. For the edge Indicator functions, and For nodes With nodes The state variable, which takes the value 0 or 1. Let v be the density value of the partitioned grid after removing edge v from the partitioned grid. and They are nodes With nodes The edge weights of the line reactance between them. For the edge Indicator functions, and For nodes With nodes The state variable, which takes the value 0 or 1. For multiplication.

[0035] In this embodiment, by introducing the GN splitting algorithm, the decision domain of each partition control node is determined before assessing the parallel stability level of the partitioned power grid. This ensures the algorithm's sensitivity to initial values ​​and the invertibility of the system impedance matrix. Its advantage lies in quantifying the grid compactness by combining the edge weights of the partitioned power grid line reactances with the total number of edges, thus compensating for the neglect of dynamic topology response in traditional methods. This meets the requirements of new power systems for rapid and reliable stability assessment.

[0036] Step S102: Select a target partition scheme with a density value within a preset range from the at least one partition scheme, and establish a parallel objective function for the partitioned power grid with the active power output of the unit and the load recovery amount as optimization variables based on the target partition scheme, the power distribution information of the grid-connected units and the load distribution information.

[0037] In this step, the expression for the objective function of the parallel regional power grid is:

[0038] ,

[0039] In the formula, Let be the overall objective function. The weighting coefficients are the active output objective function. The objective function is to output the active power. These are the weighting coefficients for the objective function of load recovery. Let the objective function be the load recovery amount. To the rated power of the units participating in the parallel operation of the zone, This refers to the active power output of the generating units during the parallel operation process. For the unit Grid connection point busbar Transient voltage stability margin during a fault busbar The short-circuit capacity margin index, For partition nodes Maximum load recovery at the location, Used to represent partition nodes Whether the load is engaged or not, the value is 0 or 1. The total number of sides of the power grid. For partition nodes Load to be restored for The weighting coefficients.

[0040] In this embodiment, an active power output objective function is introduced. With the objective function of load recovery Together they form the overall objective function With busbar The short-circuit capacity margin indicator is the starting point, while fully meeting the unit's requirements. Grid connection point busbar Under the condition of transient voltage stability margin during faults, the active power output and load recovery margin of the units during the paralleling process of the regional power grid are improved.

[0041] Step S103: Solve the objective function of the parallel grid of the zoned power grid to obtain the optimal unit start-up combination and load recovery sequence.

[0042] In this step, an optimization solver (such as CPLEX, GUROBI, or intelligent optimization algorithms) is used to solve the objective function of the regional power grid parallel operation, and a set of optimal solutions is obtained, which determines which units are started at what power and which loads are restored in what order.

[0043] Step S104: Using the optimal unit start-up combination and load recovery sequence as the initial operating state, a preset iterative method is used to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state.

[0044] In this step, an iterative method combining the Newton-Raphson method and the potential energy boundary method is used to simulate and analyze the voltage and frequency deviations when power equipment fails during the parallel operation of the regional power grid under the initial operating conditions.

[0045] Determine the voltage deviation after oscillation recovery Frequency deviation Whether the preset security constraints are met, the expression for which the preset security constraints are:

[0046] ,

[0047] In the formula, The system's rated frequency, This is the system's rated voltage;

[0048] If the conditions are not met, the frequency recovery priority reference and voltage suppression coefficient are adjusted to ensure that the oscillation range of the voltage deviation and frequency deviation meets the preset safety constraints, thereby obtaining the target voltage deviation and the target frequency deviation. The expressions for the frequency recovery priority coefficient and the voltage suppression coefficient are as follows:

[0049] ,

[0050] In the formula, This serves as a reference value for frequency recovery priority. This is the frequency recovery priority coefficient. For the maximum frequency deviation, For the unit The actual frequency deviation, The time constant of the speed controller, For the servo mechanism time constant, This is the voltage suppression coefficient. This is the voltage recovery priority coefficient. For the unit The actual voltage deviation;

[0051] The constraints are:

[0052] ,

[0053] In the formula, As a constraint on the total adjustment coefficient, For voltage control gain constraints, , They are nodes The lower and upper limits of the voltage. For nodes voltage, The total number of nodes. , They are nodes The lower and upper limits of active power, For nodes active power, , They are nodes The lower and upper limits of reactive power, For nodes reactive power, , Regional power grids Lower and upper limits for the number of capacitor banks switched on / off at a substation. For regional power grid Number of capacitor banks switched on / off at the substation , Regional power grids Lower and upper limits for the number of reactor switching groups in a substation. For regional power grid Number of reactor switching groups in a substation , These represent the lower and upper limits, respectively, for the number of reactive power compensation devices (excluding capacitors and reactors) in a regional power grid. This refers to the number of reactive power compensation devices (excluding capacitors and reactors) in a regional power grid.

[0054] If satisfied, then directly calculate the voltage deviation after oscillation recovery. Frequency deviation , respectively, are defined as the target voltage deviation and the target frequency deviation.

[0055] Figure 2 A schematic diagram of the parallel connection process of a zoned power grid is provided in a specific embodiment. The parallel connection process has the largest oscillation amplitude at the initial time sequence 1, that is, the parallel connection process of station 8 contained in zoned power grid I and station 9 contained in zoned power grid II. Figure 3 Frequency oscillation curves are provided when site 8 of zone I and site 9 of zone II are connected in parallel. Approximately 0.0183 , Approximately 0.036%, after recovery Figure 4 The voltage oscillation curves and voltage oscillation ranges of all stations within the parallel connection area are provided when station 8 of zone I and station 9 of zone II are connected in parallel. Approximately , Indicates the per-unit value. It is approximately 0.047%.

[0056] Step S105: Based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, calculate the parallel stability coefficient of the regional power grid, and determine and output the stability level of the system during the parallel connection process of the regional power grid according to the numerical range of the parallel stability coefficient of the regional power grid.

[0057] In this step, the expression for calculating the parallel stability coefficient of the partitioned power grid is:

[0058] ,

[0059] In the formula, For the parallel stability coefficient of the regional power grid, As the oscillation level factor, For the unit's inertia, For load recovery rate, This is a correction parameter for the oscillation level factor. For the maximum frequency deviation, This represents the maximum voltage fluctuation value. For the unit Rated capacity, For the unit inertia coefficient, For multiplication, The total number of sides of the power grid. For partition nodes Maximum load recovery at the location, Access bus restored for black start before parallel connection of regional power grid The load capacity, The time required to restore maximum load.

[0060] In this embodiment, by fusing the oscillation level factor Unit inertia With load recovery rate The parallel stability coefficient of the regional power grid is composed of various factors. A criterion for determining the stability of parallel operation processes in regional power grids was constructed, based on the oscillation level factor. By reasonably correcting algorithm errors, improving accuracy, real-time performance, and adaptability, quantitative indicators are provided for judging the stability of parallel grids in different zones, and rapid decision optimization is supported in multi-zone scenarios.

[0061] In summary, the method of this application, by employing the GN splitting algorithm to measure the decision domain of each control node in the power grid, establishing a parallel objective function for the parallel operation of the grid between the coupled generating units and the load recovery, and using the Newton-Raphson method and the PEBS principle to iteratively analyze the voltage and frequency oscillations during the parallel operation of the grid, and flexibly adjusting the frequency recovery priority and voltage suppression coefficient, outputs the parallel stability coefficient, etc., improves the accuracy of decision-making that previously relied solely on historical experience and preliminary human judgment, expands the rationalization of various stability indicators under multiple scenarios of power system grid parallel operation, improves the decision-making efficiency of the dispatch control center in judging system stability during the parallel operation of the grid, and ensures the safe and stable operation of the system during the parallel operation of the grid.

[0062] Please see Figure 5 The diagram shows a structural block diagram of a system stability verification system based on the parallel process of a partitioned power grid according to this application.

[0063] like Figure 5 As shown, the system stability verification system 200 includes a partitioning module 210, a construction module 220, a solution module 230, a simulation module 240, and a calculation module 250.

[0064] The partitioning module 210 is configured to acquire the topology and line parameters of the target power grid, and based on the topology and line reactance parameters, perform network partitioning using the GN splitting algorithm to obtain at least one partitioning scheme and calculate the density value of at least one partitioning scheme. The construction module 220 is configured to select a target partitioning scheme whose density value falls within a preset range from the at least one partitioning scheme, and based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, establish a parallel objective function for the partitioned power grid with active power output and load recovery as optimization variables. The solution module 230 is configured to solve the parallel objective function of the partitioned power grid to obtain... The system employs an optimal generator set start-up combination and load recovery sequence. A simulation module 240 is configured to use this optimal generator set start-up combination and load recovery sequence as the initial operating state, and employ a preset iterative method to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under this initial operating state. A calculation module 250 is configured to calculate the regional power grid parallel operation stability coefficient based on the target voltage deviation and target frequency deviation, combined with the optimal generator set start-up combination and load recovery sequence, and determine and output the system's stability level during the regional power grid parallel operation based on the numerical range of the regional power grid parallel operation stability coefficient.

[0065] It should be understood that Figure 5 The modules and references described in the document Figure 1 The steps described in the text correspond to those in the method described above. Therefore, the operations, features, and corresponding technical effects described above also apply to the method described in the text. Figure 5 The various modules in the document will not be described in detail here.

[0066] In other embodiments, the present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein when the program instructions are executed by a processor, the processor performs the system stability verification method based on the parallel process of a partitioned power grid in any of the above method embodiments.

[0067] In one embodiment, the computer-readable storage medium of the present invention stores computer-executable instructions, which are configured as follows:

[0068] Obtain the topology and line parameters of the target power grid. Based on the topology and line reactance parameters, use the GN splitting algorithm to divide the network, obtain at least one partitioning scheme, and calculate the density value of at least one partitioning scheme.

[0069] Among the at least one partitioning scheme, a target partitioning scheme with a density value within a preset range is selected. Based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, a parallel objective function for the partitioned power grid is established with the active power output of the units and the load recovery amount as optimization variables.

[0070] Solve the objective function of the parallel regional power grid to obtain the optimal unit start-up combination and load recovery sequence;

[0071] Using the optimal unit start-up combination and load recovery sequence as the initial operating state, a preset iterative method is used to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state.

[0072] Based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, the parallel stability coefficient of the regional power grid is calculated, and the stability level of the system during the parallel connection process of the regional power grid is determined and output according to the numerical range of the parallel stability coefficient of the regional power grid.

[0073] Computer-readable storage media may include a stored program area and a stored data area, wherein the stored program area may store an operating system and an application program required for at least one function; the stored data area may store data created based on the use of the system stability verification system based on the partitioned power grid paralleling process. Furthermore, the computer-readable storage medium may include high-speed random access memory, and may also include memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the computer-readable storage medium may optionally include memory remotely disposed relative to a processor, which can be connected to the system stability verification system based on the partitioned power grid paralleling process via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0074] Figure 6 This is a schematic diagram of the structure of the electronic device provided in the embodiment of the present invention, such as... Figure 6 As shown, the device includes a processor 310 and a memory 320. The electronic device may also include an input device 330 and an output device 340. The processor 310, memory 320, input device 330, and output device 340 can be connected via a bus or other means. Figure 6Taking a bus connection as an example, the memory 320 is the computer-readable storage medium described above. The processor 310 executes various server functions and data processing by running non-volatile software programs, instructions, and modules stored in the memory 320, thereby implementing the system stability verification method based on the parallel connection process of the partitioned power grid described in the above embodiment. The input device 330 can receive input digital or character information and generate key signal inputs related to user settings and function control of the system stability verification system based on the parallel connection process of the partitioned power grid. The output device 340 may include a display screen or other display device.

[0075] The aforementioned electronic device can execute the method provided in the embodiments of the present invention, and has the corresponding functional modules and beneficial effects for executing the method. Technical details not described in detail in this embodiment can be found in the method provided in the embodiments of the present invention.

[0076] In one implementation, the above-described electronic device is applied in a system stability verification system based on a partitioned power grid paralleling process, serving as a client, and includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to:

[0077] Obtain the topology and line parameters of the target power grid. Based on the topology and line reactance parameters, use the GN splitting algorithm to divide the network, obtain at least one partitioning scheme, and calculate the density value of at least one partitioning scheme.

[0078] Among the at least one partitioning scheme, a target partitioning scheme with a density value within a preset range is selected. Based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, a parallel objective function for the partitioned power grid is established with the active power output of the units and the load recovery amount as optimization variables.

[0079] Solve the objective function of the parallel regional power grid to obtain the optimal unit start-up combination and load recovery sequence;

[0080] Using the optimal unit start-up combination and load recovery sequence as the initial operating state, a preset iterative method is used to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state.

[0081] Based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, the parallel stability coefficient of the regional power grid is calculated, and the stability level of the system during the parallel connection process of the regional power grid is determined and output according to the numerical range of the parallel stability coefficient of the regional power grid.

[0082] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of various embodiments or some parts of embodiments.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A system stability verification method based on the paralleling process of a regional power grid, characterized in that, include: Obtain the topology and line parameters of the target power grid. Based on the topology and line reactance parameters, use the GN splitting algorithm to divide the network, obtain at least one partitioning scheme, and calculate the density value of at least one partitioning scheme. Among the at least one partitioning scheme, a target partitioning scheme with a density value within a preset range is selected. Based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, a parallel objective function for the partitioned power grid is established with the active power output of the units and the load recovery amount as optimization variables. Solve the objective function of the parallel regional power grid to obtain the optimal unit start-up combination and load recovery sequence; Using the optimal unit start-up combination and load recovery sequence as the initial operating state, a preset iterative method is used to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state. This includes: using an iterative method combining the Newton-Raphson method and the potential energy boundary method to simulate and analyze the voltage deviation and frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state. Determine the voltage deviation after oscillation recovery Frequency deviation Whether the preset security constraints are met, the expression for which the preset security constraints are: ， In the formula, The system's rated frequency, This is the system's rated voltage; If the conditions are not met, the frequency recovery priority reference and voltage suppression coefficient are adjusted to ensure that the oscillation range of the voltage deviation and frequency deviation meets the preset safety constraints, thereby obtaining the target voltage deviation and the target frequency deviation. The expressions for the frequency recovery priority coefficient and the voltage suppression coefficient are as follows: ， In the formula, This serves as a reference value for frequency recovery priority. This is the frequency recovery priority coefficient. For the maximum frequency deviation, For the unit The actual frequency deviation, The time constant of the speed controller, For the servo mechanism time constant, This is the voltage suppression coefficient. This is the voltage recovery priority coefficient. For the unit The actual voltage deviation; If satisfied, then directly calculate the voltage deviation after oscillation recovery. Frequency deviation , respectively, are defined as the target voltage deviation and the target frequency deviation; Based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, the parallel stability coefficient of the regional power grid is calculated, and the stability level of the system during the parallel connection process of the regional power grid is determined and output according to the numerical range of the parallel stability coefficient of the regional power grid.

2. The system stability verification method based on the parallel process of a zoned power grid according to claim 1, characterized in that, The expression for calculating the tightness value of at least one partitioning scheme is: ， In the formula, To measure the tightness of regional power grid partitioning using the GN splitting algorithm, and For nodes With nodes The edge weights of the line reactance between them. The total number of sides of the power grid. For the edge Indicator functions, and For nodes With nodes The state variable, which takes the value 0 or 1. Let v be the density value of the partitioned grid after removing edge v from the partitioned grid. and They are nodes With nodes The edge weights of the line reactance between them. For the edge Indicator functions, and For nodes With nodes The state variable, which takes the value 0 or 1. For multiplication.

3. The system stability verification method based on the parallel process of a zoned power grid according to claim 1, characterized in that, The expression for the objective function of the parallel regional power grid is: ， In the formula, Let be the overall objective function. The weighting coefficients are the active output objective function. The objective function is to output the active power. These are the weighting coefficients for the objective function of load recovery. Let the objective function be the load recovery amount. To the rated power of the units participating in the parallel operation of the zone, This refers to the active power output of the generating units during the parallel operation process. For the unit Grid connection point busbar Transient voltage stability margin during a fault busbar The short-circuit capacity margin index, For partition nodes Maximum load recovery at the location, Used to represent partition nodes Whether the load is engaged or not, the value is 0 or 1. The total number of sides of the power grid. For partition nodes Load to be restored for The weighting coefficients.

4. The system stability verification method based on the parallel process of a zoned power grid according to claim 1, characterized in that, The expression for calculating the parallel stability coefficient of the regional power grid is as follows: ， In the formula, For the parallel stability coefficient of the regional power grid, As the oscillation level factor, For the unit's inertia, For load recovery rate, This is a correction parameter for the oscillation level factor. For the maximum frequency deviation, This represents the maximum voltage fluctuation value. For the unit Rated capacity, For the unit inertia coefficient, For multiplication, The total number of sides of the power grid. For partition nodes Maximum load recovery at the location, Access bus restored for black start before parallel connection of regional power grid The load capacity, The time required to restore maximum load.

5. A system stability verification system based on the paralleling process of a regional power grid, characterized in that, include: The partitioning module is configured to acquire the topology and line parameters of the target power grid, and based on the topology and line reactance parameters, perform network partitioning using the GN splitting algorithm to obtain at least one partitioning scheme and calculate the compactness value of at least one partitioning scheme. The module is configured to select a target partitioning scheme with a density value within a preset range from the at least one partitioning scheme, and based on the target partitioning scheme, the power distribution information of the grid-connected units, and the load distribution information, establish a parallel objective function for the partitioned power grid with the active power output of the units and the load recovery amount as optimization variables. The solution module is configured to solve the parallel objective function of the regional power grid to obtain the optimal unit start-up combination and load recovery sequence; The simulation module is configured to use the optimal unit start-up combination and load recovery sequence as the initial operating state, and to use a preset iterative method to simulate and analyze the target voltage deviation and target frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state. This includes: using an iterative method combining the Newton-Raphson method and the potential energy boundary method to simulate and analyze the voltage deviation and frequency deviation when power equipment fails during the parallel operation of the regional power grid under the initial operating state. Determine the voltage deviation after oscillation recovery Frequency deviation Whether the preset security constraints are met, the expression for which the preset security constraints are: ， In the formula, The system's rated frequency, This is the system's rated voltage; If the conditions are not met, the frequency recovery priority reference and voltage suppression coefficient are adjusted to ensure that the oscillation range of the voltage deviation and frequency deviation meets the preset safety constraints, thereby obtaining the target voltage deviation and the target frequency deviation. The expressions for the frequency recovery priority coefficient and the voltage suppression coefficient are as follows: ， In the formula, This serves as a reference value for frequency recovery priority. This is the frequency recovery priority coefficient. For the maximum frequency deviation, For the unit The actual frequency deviation, The time constant of the speed controller, For the servo mechanism time constant, This is the voltage suppression coefficient. This is the voltage recovery priority coefficient. For the unit The actual voltage deviation; If satisfied, then directly calculate the voltage deviation after oscillation recovery. Frequency deviation , respectively, are defined as the target voltage deviation and the target frequency deviation; The calculation module is configured to calculate the parallel stability coefficient of the regional power grid based on the target voltage deviation and the target frequency deviation, combined with the optimal unit start-up combination and load recovery sequence, and determine and output the stability level of the system during the parallel connection process of the regional power grid according to the numerical range of the parallel stability coefficient of the regional power grid.

6. An electronic device, characterized in that, include: At least one processor, and a memory communicatively connected to the at least one processor, wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the method described in any one of claims 1 to 4.

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