Distributed checking system and method for anti-short-circuit capability of regional power grid transformer group

Abstract

The invention discloses a distributed checking system and method for anti-short-circuit capability of a regional power grid transformer group, and relates to the technical field of electric power engineering. The system comprises a distributed sensing module, a transformer group management and control module, a short-circuit checking module, a terminal centralized control module, a measurement center distributed in local power grid information, a transformer group management and control center and a regional power grid anti-short-circuit checking analysis center. According to the invention, the distributed sensing module collects data and preliminarily judges faults, the transformer group management and control module screens the faults and transformers needing to be checked, the short circuit checking module carries out multi-physics field checking, and the terminal centralized control module divides risk levels and carries out early warning. According to the method, the problems of low static checking efficiency, difficulty in adapting to power grid change and insufficient centralized computing power in the prior art are solved, dynamic and distributed checking is realized, and the operation and maintenance safety and stability of the power grid are improved.

Description

Technical Field

[0001] This invention relates to the field of power engineering technology, specifically a distributed verification system and method for the short-circuit withstand capability of a regional power grid transformer group. Background Technology

[0002] In the field of power engineering, transformers, as the core equipment for power transmission and distribution in regional power grids, directly determine the safety and stability of power grid operation due to their short-circuit withstand capability. When a short-circuit fault occurs in the power grid, the strong electromagnetic force and instantaneous high temperature generated by the short-circuit current can easily lead to transformer winding deformation, insulation damage, or even equipment failure. Therefore, accurate verification of the transformer's short-circuit withstand capability is a key aspect of power grid operation and maintenance.

[0003] Existing technologies for assessing transformer short-circuit withstand capability have established a certain research foundation. For example, Chinese patent application No. 202510428482.9, entitled "A Method for Assessing the Short-Circuit Withstand Capability of Transformer Windings," establishes an electromagnetic force-thermal calculation model and inputs relevant material property data. Through electromagnetic force-thermal coupling calculation, it obtains stress and temperature distribution data to achieve static verification of the transformer's short-circuit withstand capability. Chinese patent application No. 202211032410.5, entitled "A Simulation Calculation Method for Verifying the Short-Circuit Withstand Capability and Thermal Stability of Operating Transformers," further considers the cumulative deformation, residual stress, and thermal stability of operating transformer windings after multiple short-circuit current impacts.

[0004] It can be seen that existing assessments of the short-circuit withstand capability of power grid transformers mainly rely on static verification of each transformer before it is connected to the grid, which is inefficient. Furthermore, once a transformer is connected to a regional power grid, the short-circuit current may change accordingly with changes in the grid structure and operation mode. Moreover, short-circuit faults are numerous in the power grid, and short-circuit withstand verification centers, due to their high computing power requirements, cannot be distributed across various regional power grids. This means that existing technologies cannot use dynamic sensing of short-circuit faults to perform real-time distributed dynamic verification of the impact of each fault's short-circuit current on transformer groups at different operating locations. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies that cannot dynamically verify the short-circuit withstand capability of transformers based on changes in grid structure and power grid operation mode, and that cannot dynamically analyze the impact of short-circuit impacts on transformer groups within the regional power grid, while also addressing the problem of insufficient computing power in centralized short-circuit withstand verification, this invention proposes a distributed verification system and method for the short-circuit withstand capability of regional power grid transformer groups.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a distributed verification system for the short-circuit withstand capability of a regional power grid transformer group, wherein the regional power grid includes several local power grids, each local power grid is equipped with an information measurement center and a transformer group management and control center, the regional power grid is equipped with a short-circuit withstand verification and analysis center, distributed sensing modules are deployed in the information measurement centers of each local power grid, transformer group management and control modules and terminal centralized control modules are deployed in the transformer group management and control centers of each local power grid, and a short-circuit verification module is deployed in the short-circuit withstand verification and analysis center; The distributed sensing module is used to collect the operating parameter group and topology parameter group of the transformer group, and normalize them to provide data for group coupling calculation and output the standardized group dataset to the transformer group management and control module. The transformer group management module stores the basic equipment parameters of the transformers in the local power grid. Based on the basic equipment parameters and the operating parameters and topology parameters of the distributed sensing module, it establishes a transformer-line-node topology association table. Based on the group topology and transient operating data, it classifies the group short-circuit fault types and calculates the short-circuit current of each transformer based on the group impedance data, outputting the results to the short-circuit verification module. The group impedance data includes the transformer's own impedance, line impedance, and node impedance. The short-circuit verification module is used to perform multi-physics field verification on each transformer in the group according to priority, and output the group verification results to the terminal control module. The terminal control module is deployed in the local power grid transformer group management and control center. It is used to classify and store transformer data within the transformer group, classify the risks of the transformer group, and issue early warnings for transformers that need to be re-verified statically.

[0007] Further optimized, the distributed sensing module employs a four-feature group dynamic early warning triggering condition based on transformer groups: "current surge - voltage drop - time transient - harmonic distortion," to initially determine whether a short-circuit fault has occurred. Only when a short-circuit fault is determined, the standardized group dataset and fault early warning signal are simultaneously pushed to the transformer group management module. The four-feature group dynamic early warning triggering condition is specifically as follows: and and and ; Where m is the number of transformers in the group affected by the fault and connected to the faulty node, and k is the ordinal number of the affected transformer. Let be the peak value of the short-circuit current of the k-th transformer. Let be the average steady-state current before the failure of the k-th transformer. Let be the valley value of the short-circuit voltage of the k-th transformer. The rated voltage of the kth transformer is... The duration of the fault of the k-th transformer. For power frequency cycle, Total harmonic distortion rate of the short-circuit current of the kth transformer.

[0008] Furthermore, the transformer group management module acquires basic parameter groups, operating parameter groups, and topology parameter groups of equipment in the local power grid for the transformer group within the local power grid. It then associates the transformers and lines in the data according to the physical node dimension and associates the transformer transient information according to the timestamp dimension to obtain a transformer-line-node topology association table.

[0009] More preferably, the transformer group management module performs secondary confirmation of short-circuit faults based on the short-circuit faults detected by the distributed sensing module, and filters the affected transformer groups: Based on initial screening of electrical connections, the location of the fault point connected to the transformer group was identified. Equipment with no electrical connection was excluded based on transformers directly or indirectly connected by lines. Screening criteria: ; Let k be the electrical distance between the k-th transformer and the fault point. Let K be the positive sequence equivalent impedance of the k-th transformer and the fault point. For line impedance, This is the actual length of the line. The maximum interconnection distance of the regional power grid; To exclude transformers whose short-circuit current is significantly attenuated due to line impedance, a secondary screening is performed, retaining only transformers whose short-circuit current is within the allowable range. Screening criteria: ,in, Let RMS value be the short-circuit current flowing into the k-th transformer. The effective value of the short-circuit current at the fault point is obtained by the distributed sensing module collecting data from the current transformer at the fault point. This is the short-circuit current decay threshold.

[0010] More preferably, the transformer group management module uses a two-dimensional impact intensity index of "short-circuit current multiple - duration". The impact of quantification shock on transformers only when When the impact strength exceeds the threshold, the signal is sent to the short-circuit verification module. ; ; in, Let be the multiple of the short-circuit current of the k-th transformer. , Rated current; The duration of the short-circuit impact on the k-th transformer; The impact strength threshold is typically set to 0.6 for control.

[0011] More preferably, the short-circuit verification module receives transformer parameters from the verification list pushed by the transformer group management module, performs geometric modeling based on the transformer parameters to generate a three-dimensional geometric model, and then uses the measured transient short-circuit current waveform collected by the distributed sensing module as current excitation to the high, medium and low voltage winding terminals of the transformer. The short-circuit verification module uses an electromagnetic-force coupling field to verify the dynamic stability of the transformer under short-circuit impact; the short-circuit verification module uses an electromagnetic-thermal coupling field to verify the thermal stability of the transformer under short-circuit impact; the short-circuit verification module outputs a verification report for each transformer to be verified, including "dynamic stability index + thermal stability index + whether it meets the standard", and feeds it back to the terminal control module.

[0012] In a further preferred embodiment, the terminal control module receives the verification report, assesses and classifies the overall risk level of the transformer group within the regional power grid, and implements differentiated cluster management and early warning for the transformers within the group based on the assessment and classification results, and uniformly schedules and manages the batches of transformers that need to be re-verified.

[0013] This invention also provides a distributed verification method for the short-circuit withstand capability of a regional power grid transformer group, the steps of which are as follows: Step 1: The distributed sensing module connects the power dispatching system and the auxiliary control system to collect, classify, transmit and store the operating mode and transformer multi-source state variable data in the local power grid. Based on the transformer rated parameters and power grid safety criteria, a short-circuit fault early warning threshold is set. When the fault early warning threshold is reached, the distributed sensing module transmits the fault early warning signal and transformer multi-source state variable data to the transformer group management module. Step 2: The transformer group management module receives the fault warning signal and transformer multi-source state variable data pushed by the distributed sensing module, performs secondary confirmation of short circuit faults and screening of transformers that need to be checked, and determines the impact intensity threshold of the confirmed short circuit faults. Step 3: After receiving the verification request, the short-circuit verification module performs multi-physics finite element modeling on the transformer to be verified, and verifies the transformer impact based on the short-circuit fault of the regional power grid. Step 4: Based on the verification results, the terminal control module classifies the overall risk level of the transformer group and implements clustered early warning and scheduling decisions.

[0014] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores computer-executable instructions, and the processor invokes the computer-executable instructions to perform various steps of the distributed verification method for the short-circuit withstand capability of the regional power grid transformer group.

[0015] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the various steps of the above-described distributed verification method for the short-circuit withstand capability of regional power grid transformer groups.

[0016] The present invention has the following advantages: Existing technologies rely on static verification of each transformer before it is connected to the grid, which cannot adapt to changes in short-circuit current caused by changes in the grid structure and operating mode. In this invention, the distributed sensing module collects operating and topology parameters in real time, and dynamically determines faults by combining four characteristics: "current surge - voltage drop - time transient - harmonic distortion". The transformer group management module updates the short-circuit current calculation accordingly, and the short-circuit verification module dynamically performs multi-physics field verification to ensure that the verification results always match the real-time state of the grid and avoid verification failure due to grid changes.

[0017] Traditional short-circuit withstand verification centers are difficult to distribute due to their high computing power requirements, making them unable to handle numerous short-circuit faults in the power grid. This system deploys distributed sensing modules and transformer group management modules in various local power grids, with only the short-circuit verification module deployed in the regional power grid short-circuit withstand verification and analysis center. Data preprocessing, initial fault identification, and screening are completed in the local power grids first, and only the data of transformers requiring precise verification is uploaded, significantly reducing data transmission volume and centralized computing power consumption, thus achieving efficient verification of multiple faults and multiple transformers within the regional power grid.

[0018] The transformer group management module uses dual screening based on electrical distance and short-circuit current attenuation to exclude unrelated and weakly impacted transformers, reducing the number of transformers requiring verification. The short-circuit verification module employs a meshing strategy of "winding densification + core / tank simplification," saving computational power while ensuring accuracy. It also performs dynamic and thermal stability verification according to IEC standards to ensure accurate results. The terminal centralized control module implements hierarchical management based on verification current ratios and verification results, enabling differentiated early warning and dispatching. This improves the targeting and efficiency of grid operation and maintenance, reduces transformer failure risks, and ensures the safe and stable operation of the power grid. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the distributed verification system for the short-circuit withstand capability of a regional power grid transformer group according to the present invention. Detailed Implementation

[0020] The present invention will be further explained in detail below with reference to the accompanying drawings and embodiments.

[0021] like Figure 1As shown, a distributed verification system for the short-circuit withstand capability of a transformer group in a regional power grid is provided. The regional power grid includes several local power grids (such as a municipal power grid). Each local power grid is equipped with an information measurement center and a transformer group management and control center. The regional power grid is equipped with a short-circuit withstand verification and analysis center. Distributed sensing modules are deployed in the information measurement centers of each local power grid. Transformer group management and control modules and terminal centralized control modules are deployed in the transformer group management and control centers of each local power grid. A short-circuit verification module is deployed in the short-circuit withstand verification and analysis center. The distributed sensing module is used to collect and normalize the operating parameter group and topology parameter group of the transformer group, providing data for group coupling calculation and outputting standardized transformer multi-source state variable data to the transformer group management module. The operating parameter group includes: three-phase current and voltage waveform data, active / reactive power, and switch status of the high, medium, and low voltage sides of the transformer. The data comes from instrument transformers and smart terminals installed on the transformer circuits. The topology parameter group includes the connection relationships of transformers, lines, and circuit breakers, as well as the node numbers and their affiliated regions. Data normalization processing includes: unit unification (current is unified to kA, voltage is unified to kV); time alignment, using the fault initiation time as the time zero point, interpolating and synchronizing the transient data of all transformers in the group; and format standardization, converting the waveform data into the power system standard COMTRADE format to form standardized transformer multi-source state variable data.

[0022] The aforementioned topology parameter group refers to the transformer group-line-node associated topology, which consists of all transformers, connecting lines, and access nodes within the local power grid. It is associated through physical node dimension (including the hardware connection relationship between transformers and access nodes and lines) and timestamp dimension (including the synchronization of transformer transient operation data and fault time), forming a spatiotemporal connection relationship of the local power grid, which can intuitively reflect the electrical conduction path between the fault point and the transformer group.

[0023] The transformer group management module stores the basic equipment parameters of the local power grid transformers, including the inner and outer diameters of the windings, axial length, conductor resistivity, material elastic modulus, coefficient of thermal expansion, core loss parameters, transformer manufacturer, and production batch for each transformer. It establishes a transformer-line-node topology association table based on the basic equipment parameters, the operating parameters from the distributed sensing module, and the topology parameters. Based on the topology parameters and transient operating data, it classifies short-circuit fault types and calculates the short-circuit current for each transformer based on the group impedance data, outputting the results to the short-circuit verification module. The group impedance data is the core set of parameters supporting short-circuit current calculations, including three categories: Transformer impedance: Taken from the equipment basic parameter group, including high, medium and low voltage sides, uniformly converted to 75℃ short-circuit impedance; Line impedance: Taken from the topology parameter group, including the positive sequence impedance and zero sequence impedance of all connecting lines from the fault point to the transformer (considering the differences in short-circuit fault types). Node impedance: Taken from the topology parameter group, including the equivalent impedance of the transformer-connected node (reflecting the connection strength between the node and the main power grid).

[0024] The short-circuit verification module is used to perform multi-physics field verification on each transformer in the group according to priority, and output the group verification results to the terminal control module. The terminal control module is deployed in the local power grid transformer group management and control center. It is used to classify and store transformer data within the transformer group, classify the risks of the transformer group, and issue early warnings for transformers that need to be re-verified statically.

[0025] The distributed sensing module adopts a dynamic early warning trigger condition based on a transformer group of four characteristics: "current surge - voltage drop - time transient - harmonic distortion" to initially determine whether a short circuit fault has occurred, thus avoiding false triggering by a single device.

[0026] Only when a short-circuit fault is determined, the standardized cluster dataset (including the transformer-line-node topology association table and transient operation data) and the fault warning signal are simultaneously pushed to the transformer group management module to provide data support for subsequent processes.

[0027] The four-feature group dynamic early warning trigger condition is based on the aforementioned collected operating parameter group (three-phase current, voltage, fault recording time, harmonic data). The four-feature group dynamic early warning trigger condition is set as follows: and and and ; The above four conditions must be met simultaneously for a short-circuit fault to be detected; otherwise, it is considered a non-short-circuit disturbance and the subsequent process is not triggered. This triggering mechanism can effectively avoid misjudgments caused by measurement errors of a single device. Where m is the number of transformers in the fault-affected group connected to the fault node, and k is the ordinal number of the affected transformer. Let be the peak value of the short-circuit current of the k-th transformer. Let be the average steady-state current before the failure of the k-th transformer. Let be the valley value of the short-circuit voltage of the k-th transformer. The rated voltage of the kth transformer is... The duration of the fault of the k-th transformer. For power frequency cycle, Total harmonic distortion rate of the short-circuit current of the kth transformer.

[0028] Furthermore, the transformer group management module acquires basic parameter groups, operating parameter groups, and topology parameter groups of equipment in the local power grid for the transformer group within the local power grid. It associates transformers and lines in the data according to the physical node dimension, and associates transformer transient information according to the timestamp dimension, to obtain a transformer-line-node topology association table, as shown in Table 1.

[0029] Table 1. Transformer-Line-Node Topology Association Table

[0030] Furthermore, the transformer group management module performs secondary confirmation of short-circuit faults based on the short-circuit faults detected by the distributed sensing module, and filters the affected transformer groups.

[0031] Based on initial screening of electrical connections, the location of the fault point connected to the transformer group was identified. Equipment with no electrical connection was excluded based on transformers directly or indirectly connected by lines. Screening criteria: ,in, Let k be the electrical distance between the k-th transformer and the fault point. Let K be the positive sequence equivalent impedance of the k-th transformer and the fault point. For line impedance, This is the actual length of the line. The maximum interconnection distance of the regional power grid is set according to the voltage level; 50km for 220kV power grid and 30km for 110kV power grid.

[0032] To exclude transformers whose short-circuit current is significantly attenuated due to line impedance, a secondary screening is performed, retaining only transformers whose short-circuit current is within the allowable range. Screening criteria: ,in, Let RMS value be the short-circuit current flowing into the k-th transformer. The effective value of the short-circuit current at the fault point is obtained by the distributed sensing module collecting data from the current transformer at the fault point. The short-circuit current attenuation threshold (for transformers of 110kV and above). Taking 0.3 means that when the transformer short-circuit current is less than 30% of the fault point current, the impact strength is weak and no verification is required.

[0033] Furthermore, the transformer group management module uses a two-dimensional impact intensity index of "short-circuit current multiple - duration" to... The impact of quantification shock on transformers only when When the impact strength exceeds the threshold, the signal is sent to the short-circuit verification module. ; ; in, Let be the multiple of the short-circuit current of the k-th transformer. , Rated current; The duration of the short-circuit impact on the k-th transformer; The impact strength threshold is typically set to 0.6 for control.

[0034] Furthermore, the short-circuit verification module receives transformer parameters from the verification list pushed by the transformer group management module. These parameters include winding inner diameter, outer diameter, axial height, number of coils, number of supports, conductor resistivity, material elastic modulus, coefficient of thermal expansion, and core loss. Based on these parameters, geometric modeling is performed, automatically generating three-dimensional geometric models of the windings (multi-strand wire windings), core (laminated structure), clamps, and tank. For 110kV and above transformers, the high-voltage side defaults to a star connection (neutral point directly grounded), while the medium and low-voltage sides default to a delta connection. A strategy of "refining the winding area and simplifying non-critical areas" is adopted. Specifically, a fine hexahedral mesh with a size less than 5mm is used for the winding conductors and their insulation areas; a tetrahedral mesh with a size of 20-50mm is used for the core, tank, and other structures. This strategy saves computational power while ensuring calculation accuracy. The measured transient short-circuit current waveform collected by the distributed sensing module is then used as the current excitation and applied to the high, medium, and low voltage winding terminals of the transformer. The transient electromagnetic field is solved, and the force on each winding coil is calculated. The time step setting is as follows: a small step is used during the short-circuit duration to ensure the capture of the peak value of the transient electromagnetic force; a large step is used after the duration.

[0035] Furthermore, the short-circuit verification module applies an electromagnetic-force coupled field to verify the dynamic stability of the transformer under short-circuit impact. The electromagnetic force is used as a load and imported into the structural mechanics module. Material properties such as the elastic modulus and Poisson's ratio of the winding copper are set, and the transient dynamic equations are solved to obtain the displacement, stress, and strain fields of the winding. Based on the method provided in IEC 60076-5 standard "Power Transformers - Part 5: Short-Circuit Withstand Capacity", the maximum mechanical stress of the winding under the measured transient short-circuit current is calculated using the structural mechanics equations. Specifically, the mechanical stress can be calculated using the following formula: ; in, Here, E is the mechanical stress, E is the elastic modulus of the winding material, and ε is the winding strain calculated using the electromagnetic-force coupling field. The ratio of the maximum mechanical stress to the conductor cross-sectional area must be less than the yield strength of the copper conductor used in the transformer (usually the yield strength of copper conductor ≥ 160 MPa); otherwise, the short-circuit withstand test is deemed unqualified.

[0036] The thermal stability of a transformer under short-circuit impact is verified using an electromagnetic-thermal coupled field. The Joule heat during the short circuit is calculated based on the calculated short-circuit current and winding DC resistance, and this is used as a transient heat source. Based on the method provided in IEC 60076-7 standard "Power Transformers - Part 7: Loading Guidelines for Oil-Immersed Power Transformers", the thermal conductivity, specific heat capacity, and oil-to-winding heat dissipation coefficient of the winding are set in the thermal analysis module. The transient heat source is imported into the thermal analysis module, and the maximum temperature rise of the winding is calculated in the finite element model based on the heat conduction equation under the measured transient short-circuit current. The thermal stress is then calculated based on the maximum temperature rise of the winding and the thermal expansion equation. ; in, Where α is thermal stress and α is the coefficient of thermal expansion of the winding. The maximum temperature rise of the winding is calculated for the electromagnetic-thermal coupling field, where v is the Poisson's ratio of the winding material, describing the ratio of transverse strain to axial strain. According to the IEC 60076-7 standard, the temperature rise of the hottest spot in the winding must meet the following requirements: the maximum temperature rise of the winding is less than 80℃ and the thermal stress is less than 200MPa; otherwise, the short-circuit withstand test is deemed unqualified.

[0037] Furthermore, the short-circuit verification module outputs a verification report for each transformer requiring verification, including "dynamic stability index + thermal stability index + whether it meets the standard," and feeds it back to the terminal control module.

[0038] Furthermore, the terminal control module receives the verification report, assesses and classifies the overall risk level of the transformer group in the regional power grid, and implements differentiated cluster management and early warning for the transformers in the group based on the assessment and classification results (as shown in Table 2). It also performs unified scheduling and management for the batch of transformers that need to be re-verified.

[0039] Table 2

[0040] Among them, the verification current ratio , The measured effective value of the short-circuit current collected by the distributed sensing module. The measured peak value of the short-circuit current is collected by the distributed sensing module. This is the short-circuit current value selected during the static short-circuit withstand verification of the transformer before it is connected to the grid.

[0041] Another embodiment of the present invention provides a distributed verification method for the short-circuit withstand capability of a regional power grid transformer group, the steps of which are as follows: Step 1: The distributed sensing module connects the power dispatching system and the auxiliary control system to collect, classify, transmit and store the operating mode and transformer multi-source state variable data in the local power grid. Based on the transformer rated parameters and power grid safety criteria, a short-circuit fault early warning threshold is set. When the fault early warning threshold is reached, the distributed sensing module transmits the fault early warning signal and transformer multi-source state variable data to the transformer group management module. Step 2: The transformer group management module receives the fault warning signal and transformer multi-source state variable data pushed by the distributed sensing module, performs secondary confirmation of short circuit faults and screening of transformers that need to be checked, and determines the impact intensity threshold of the confirmed short circuit faults. Step 3: After receiving the verification request, the short-circuit verification module performs multi-physics finite element modeling on the transformer to be verified, and verifies the transformer impact based on the short-circuit fault of the regional power grid. Step 4: Based on the verification results, the terminal control module classifies the overall risk level of the transformer group and implements clustered early warning and scheduling decisions.

[0042] Another embodiment of the present invention provides an electronic device including a memory and a processor, the memory storing computer-executable instructions, the processor invoking the computer-executable instructions to perform various steps of the distributed verification method for the short-circuit withstand capability of the regional power grid transformer group.

[0043] Another embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the various steps of the above-described distributed verification method for the short-circuit withstand capability of a regional power grid transformer group.

[0044] The above description merely illustrates preferred embodiments of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make modifications or alterations to the above-disclosed content to create equivalent embodiments. However, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A distributed verification system for the short-circuit withstand capability of a regional power grid transformer group, characterized in that, The regional power grid includes several local power grids. Each local power grid has an information measurement center and a transformer group management and control center. The regional power grid has a short-circuit resistance verification and analysis center. Distributed sensing modules are deployed in the information measurement centers of each local power grid. Transformer group management and control modules and terminal centralized control modules are deployed in the transformer group management and control centers of each local power grid. Short-circuit verification modules are deployed in the short-circuit resistance verification and analysis center. The distributed sensing module is used to collect the operating parameter group and topology parameter group of the transformer group, and normalize them to provide data for group coupling calculation and output the standardized group dataset to the transformer group management and control module. The transformer group management module is used to store the basic equipment parameter group of local power grid transformers, and to establish a transformer-line-node topology association table based on the basic equipment parameter group, the operating parameter group and topology parameter group data of the distributed sensing module; The group short-circuit fault types are classified based on group topology and transient operation data. The short-circuit current of each transformer is calculated based on group impedance data and output to the short-circuit verification module. The group impedance data includes the transformer's own impedance, line impedance, and node impedance. The short-circuit verification module is used to perform multi-physics field verification on each transformer in the group according to priority, and output the group verification results to the terminal control module. The terminal control module is deployed in the local power grid transformer group management and control center. It is used to classify and store transformer data within the transformer group, classify the risks of the transformer group, and issue early warnings for transformers that need to be re-verified statically.

2. The distributed verification system for the short-circuit withstand capability of regional power grid transformer groups according to claim 1, characterized in that, The distributed sensing module employs a four-feature group dynamic early warning trigger condition based on transformer groups: "current surge - voltage drop - time transient - harmonic distortion," to initially determine whether a short-circuit fault has occurred. Only when a short-circuit fault is determined will the standardized group dataset and fault early warning signal be synchronously pushed to the transformer group management module. The four-feature group dynamic early warning trigger condition is as follows: and and and ; Where m is the number of transformers in the group affected by the fault and connected to the faulty node, and k is the ordinal number of the affected transformer. Let be the peak value of the short-circuit current of the k-th transformer. Let be the average steady-state current before the failure of the k-th transformer. Let be the valley value of the short-circuit voltage of the k-th transformer. The rated voltage of the kth transformer is... The duration of the fault of the k-th transformer. For power frequency cycle, Total harmonic distortion rate of the short-circuit current of the kth transformer.

3. The distributed verification system for the short-circuit withstand capability of regional power grid transformer groups according to claim 1, characterized in that, The transformer group management module acquires basic parameter groups, operating parameter groups, and topology parameter groups of equipment in the local power grid for transformer groups. It associates transformers and lines in the data according to the physical node dimension and associates transformer transient information according to the timestamp dimension to obtain a transformer-line-node topology association table.

4. The distributed verification system for the short-circuit withstand capability of a regional power grid transformer group according to claim 1, characterized in that, The transformer group management module performs secondary confirmation of short-circuit faults based on the short-circuit faults detected by the distributed sensing module, and filters the affected transformer groups: Based on initial screening of electrical connections, the location of the fault point connected to the transformer group was identified. Equipment with no electrical connection was excluded based on transformers directly or indirectly connected by lines. Screening criteria: , Let k be the electrical distance between the k-th transformer and the fault point. Let K be the positive sequence equivalent impedance of the k-th transformer and the fault point. For line impedance, This is the actual length of the line. The maximum interconnection distance of the regional power grid; A second screening is conducted, retaining only transformers with short-circuit currents within the allowable range. Screening criteria: ,in, Let RMS value be the short-circuit current flowing into the k-th transformer. The effective value of the short-circuit current at the fault point is obtained by the distributed sensing module collecting data from the current transformer at the fault point. This is the short-circuit current decay threshold.

5. The distributed verification system for the short-circuit withstand capability of a regional power grid transformer group according to claim 1, characterized in that, The transformer group management module uses a two-dimensional impact intensity index of "short-circuit current multiple - duration" to determine the impact intensity. The impact of quantification shock on transformers only when When the impact strength exceeds the threshold, the signal is sent to the short-circuit verification module. ； ； in, Let be the multiple of the short-circuit current of the k-th transformer. , Rated current; The duration of the short-circuit impact on the k-th transformer; This is the impact strength threshold.

6. The distributed verification system for the short-circuit withstand capability of regional power grid transformer groups according to claim 1, characterized in that, The short-circuit verification module receives transformer parameters from the verification list pushed by the transformer group management module, performs geometric modeling based on the transformer parameters, generates a three-dimensional geometric model, and then uses the measured transient short-circuit current waveform collected by the distributed sensing module as current excitation, which is applied to the high, medium and low voltage winding terminals of the transformer. The short-circuit verification module uses an electromagnetic-force coupling field to verify the dynamic stability of the transformer under short-circuit impact; the short-circuit verification module uses an electromagnetic-thermal coupling field to verify the thermal stability of the transformer under short-circuit impact; the short-circuit verification module outputs a verification report for each transformer to be verified, including "dynamic stability index + thermal stability index + whether it meets the standard", and feeds it back to the terminal control module.

7. The distributed verification system for the short-circuit withstand capability of regional power grid transformer groups according to claim 1, characterized in that, The terminal control module receives the verification report, assesses and classifies the overall risk level of the transformer group in the regional power grid, and implements differentiated cluster management and early warning for the transformers in the group based on the assessment and classification results. It also performs unified scheduling and management for batches of transformers that need to be re-verified.

8. A distributed verification method for the short-circuit withstand capability of a regional power grid transformer group based on the system described in any one of claims 1-7, characterized in that, The steps are as follows: Step 1: The distributed sensing module connects the power dispatching system and the auxiliary control system to collect, classify, transmit and store the operating mode and transformer multi-source state variable data in the local power grid. Based on the transformer rated parameters and power grid safety criteria, a short-circuit fault early warning threshold is set. When the fault early warning threshold is reached, the distributed sensing module transmits the fault early warning signal and transformer multi-source state variable data to the transformer group management module. Step 2: The transformer group management module receives the fault warning signal and transformer multi-source state variable data pushed by the distributed sensing module, performs secondary confirmation of short circuit faults and screening of transformers that need to be checked, and determines the impact intensity threshold of the confirmed short circuit faults. Step 3: After receiving the verification request, the short-circuit verification module performs multi-physics finite element modeling on the transformer to be verified, and verifies the transformer impact based on the short-circuit fault of the regional power grid. Step 4: Based on the verification results, the terminal control module classifies the overall risk level of the transformer group and implements clustered early warning and scheduling decisions.

9. An electronic device comprising a memory and a processor, the memory storing computer-executable instructions, characterized in that, The processor invokes computer-executable instructions to execute each step of the distributed verification method for the short-circuit withstand capability of a regional power grid transformer group as described in claim 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements each step of the distributed verification method for the short-circuit withstand capability of regional power grid transformer groups as described in claim 8.

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