Method and system for quickly verifying the phase correctness of a neutral non-grounded system power grid

Abstract

The application discloses a method and system for quickly and batch verifying correctness of phases of a neutral point ungrounded system power grid, and utilizes voltage characteristics (one-phase reduction Delta U1 and two-phase increase Delta U2) of single-phase grounding fault of the neutral point ungrounded system to automatically trigger verification; a "reference bus voltage library" is constructed, and verified double power sources or superior power supply stations are automatically matched as reference references; a zero sequence voltage amplitude checking mechanism is innovatively introduced, on the basis of preliminary determination of phase consistency, further checking amplitude differences of each phase voltage and zero sequence voltage of the to-be-verified station and the reference station is performed; if the differences are all within a preset threshold Delta U, data is automatically included in the reference library to realize dynamic updating; if any difference is out of limit, an artificial closed-loop processing flow is triggered, and manual checking and correction are forced to be performed before the data can be stored in the library. Through the cooperative mechanism of "fault triggering + zero sequence checking + man-machine closed loop", the application realizes automation, high reliability and continuous self-evolution of reference data of the phase verification of the power grid.

Description

Technical Field

[0001] This invention belongs to the field of power system operation, maintenance and automation technology, and in particular relates to a method and system for rapidly batch verifying the phase correctness of a neutral-point ungrounded power grid. Background Technology

[0002] In 35kV and 10kV ungrounded neutral systems, phase sequence or phase errors often occur during the commissioning of newly built, expanded, or renovated equipment due to incorrect wiring during construction. If loop-closing is performed without verification, it can lead to serious accidents. Existing phase verification methods have the following drawbacks:

[0003] 1. Verification of single power supply stations is difficult: For single power supply stations, there is a lack of a second power source for direct comparison. Traditional methods require power outages or the use of dedicated testing equipment, which is inefficient and costly.

[0004] 2. Risks to the Quality of Reference Data: Existing methods often focus only on the phase consistency of three-phase voltages, neglecting the amplitude verification of zero-sequence voltage. If a substation has anomalies in zero-sequence voltage due to errors in the zero-sequence voltage transformer (PT) ratio, incorrect acquisition coefficient configuration, or significant differences in transition resistance at the grounding fault point, relying solely on three-phase voltage comparison may mistakenly include the substation with abnormal data in the reference database. Once erroneous data enters the reference database, it will cause a chain reaction of errors in subsequent cascaded verifications based on that reference, seriously affecting power grid safety.

[0005] 3. Lack of closed-loop processing mechanism: When data anomalies are detected, existing systems often only prompt errors, lacking a closed-loop process of "pause data entry - manual processing - confirmation of data entry". This results in abnormal data either being incorrectly entered into the database or being directly discarded and unusable, making it impossible to continuously accumulate verification capabilities.

[0006] 4. Excessive human intervention: The lack of automated fault identification, benchmark selection, and result entry processes makes it prone to errors and omissions due to reliance on manual judgment and recording. Summary of the Invention

[0007] To address the aforementioned problems, this invention provides a method and system for rapidly verifying the phase correctness of a neutral-point ungrounded system power grid in batches.

[0008] The present invention provides a method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid, comprising the following steps:

[0009] Step 1: Monitor the neutral point ungrounded system power grid in real time. When it is detected that the single-phase voltage of any bus at any station drops to the threshold ΔU1, and the voltage of the other two phases of the same bus rises to the threshold ΔU2, the phase verification process is automatically triggered and started.

[0010] Step 2: Collect bus three-phase voltage data and zero-sequence voltage data of all relevant substations within the fault power supply area through the power grid automation system.

[0011] Step 3: Call the established reference bus voltage library, automatically match and select the bus voltage data of the dual-power station or the upstream power station in the area with verified correct phase by bus name or grid topology as the reference phase reference; if automatic matching fails, output a prompt to manually select the reference phase reference.

[0012] Step 4: Based on the characteristics of single-phase grounding faults in a neutral-point ungrounded system, analyze the voltage distribution characteristics of the reference base to determine the current fault phase.

[0013] Step 5: Compare the three-phase bus voltage data of the substation to be verified in the area with the fault phase and voltage value characteristics of the reference benchmark.

[0014] Step 6: Determine the phase correctness of the plant to be verified based on the comparison results: If the low voltage phase of the plant to be verified is consistent with the fault phase of the reference benchmark, and the voltage rise of the non-fault phase meets the theoretical characteristics, then the phase is preliminarily determined to be correct; otherwise, the phase is determined to be incorrect.

[0015] Step 7: Generate a phase verification report and a bus voltage comparison report. For substations that are determined to have phase errors, generate an abnormal alarm and push it to the relevant maintenance department for rectification.

[0016] Step 8: For the substation bus voltage that was initially determined to be correct in phase in Step 6, further verify whether the differences between the phase voltage amplitude and zero-sequence voltage amplitude of this bus and the phase voltage amplitude and zero-sequence voltage amplitude of the reference base do not exceed the preset threshold ΔU. If all differences do not exceed ΔU, the substation bus voltage data will be automatically pushed to the reference bus voltage database to update the database. If any difference exceeds ΔU, a manual processing prompt will be generated, automatic data entry will be paused, and manual verification and processing will be performed before the substation bus voltage data is pushed to the reference bus voltage database to update the database.

[0017] Furthermore, in step 1, the threshold ΔU1 is set to below 80% of the normal phase voltage, and the threshold ΔU2 is set to above 130% of the normal phase voltage, which are used to identify the characteristics of single-phase grounding faults in a neutral-point ungrounded system.

[0018] Furthermore, in step 3, the reference bus voltage library stores the verified phase correct substation bus and its topology association information; the automatic selection logic prioritizes the verified substation with the closest electrical connection distance or the most direct power supply path to the substation to be verified as the reference benchmark.

[0019] Furthermore, in step 6, the phrase "the increase in voltage of the non-faulty phase conforms to theoretical characteristics" means that the voltage of the non-faulty phase increases to the level of the normal phase voltage. The voltage is approximately twice that of the three phases, and the three-phase line voltages remain symmetrical.

[0020] Furthermore, in step 7, the abnormal alarm includes the incorrect plant name, incorrect phase, voltage comparison data, and suggested corrective measures; if step 8 triggers manual processing, the alarm content will additionally include detailed information such as "voltage amplitude or zero-sequence voltage deviation exceeds the limit, manual review is required".

[0021] Furthermore, in step 8, manual processing includes: the system generating a work order containing the name of the plant to be verified, the over-limit voltage component, the deviation value, and the suggested inspection items; after the manual completion of on-site verification or system parameter correction, a "verification passed" confirmation operation is performed in the system, and the system then performs the warehousing operation.

[0022] Furthermore, step 8 enables the dynamic expansion and quality closed-loop control of the reference bus voltage library.

[0023] The system for implementing the above-described method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid includes:

[0024] Monitoring module: Used to monitor the grid bus voltage in real time and identify single-phase grounding faults that meet the conditions ΔU1 and ΔU2.

[0025] Data acquisition module: Used to collect three-phase and zero-sequence voltage data of each power plant in the fault area through the power grid automation system.

[0026] Reference Management Module: Used to maintain the reference bus voltage library, execute the logic of automatically or manually selecting reference references, and receive requests to add new verification data to the library.

[0027] Analysis and comparison module: used to determine the faulty phase, compare the voltage characteristics of the substation to be verified with the reference reference, and determine the phase correctness.

[0028] Multidimensional verification and manual review module: used to calculate the difference between the plant to be verified and the reference benchmark in terms of three-phase voltage amplitude and zero-sequence voltage amplitude; if all differences meet the ΔU threshold, the entry instruction is automatically triggered; if any difference exceeds ΔU, a manual review work order is generated and the entry status is locked, waiting for manual confirmation instruction.

[0029] Report push module: Used to generate verification reports, comparison reports and anomaly alarms, and push them to relevant terminals.

[0030] The beneficial technical effects of this invention compared to the prior art are as follows:

[0031] 1. Combination of automation and manual operation: The entire process from fault identification to result entry into the database is automated, while a rigorous closed-loop manual handling mechanism is designed for abnormal situations, balancing efficiency and security.

[0032] 2. High reliability of the benchmark library: Through dual verification of three-phase + zero sequence, data anomalies caused by incorrect acquisition coefficients and PT failures are effectively filtered out, preventing "faulty" data from contaminating the benchmark library and ensuring the accuracy of subsequent cascade verification.

[0033] 3. Precisely locate potential problems: The introduction of zero-sequence voltage verification can detect configuration errors in the acquisition system that cannot be identified by three-phase voltage alone (such as incorrect zero-sequence voltage coefficient settings), and accurately locate and resolve the problems through manual processing.

[0034] 4. Continuous accumulation of verification capabilities: Through the mechanism of "automatic entry into the database + manual correction before entry into the database", all single power supply stations that have been verified correctly (including stations that have been manually corrected) can be transformed into new benchmarks, realizing the dynamic expansion of the verification scope and full network coverage. Attached Figure Description

[0035] Figure 1 A flowchart of a method for rapidly verifying the phase correctness of a neutral-point ungrounded power grid in batches.

[0036] Figure 2 This is a schematic diagram of the normal operating voltage.

[0037] Figure 3 This is the voltage during a single-phase ground fault (taking phase A metallic ground fault as an example).

[0038] Figure 4 This is a schematic diagram of the power grid area in Example 1 (black squares in the diagram indicate the switch closed position, and white squares represent the switch open position).

[0039] Figure 5 This is a schematic diagram of the power grid area in Example 2 (black squares in the diagram indicate the switch closed position, and white squares represent the switch open position). Detailed Implementation

[0040] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0041] The flowchart of a method for rapid batch verification of the phase correctness of a neutral-point ungrounded system power grid is as follows: Figure 1 As shown, it includes the following steps:

[0042] Step 1: Monitor the neutral point ungrounded system power grid in real time. When it is detected that the single-phase voltage of any bus at any station drops to the threshold ΔU1, and the voltage of the other two phases of the same bus rises to the threshold ΔU2, the phase verification process is automatically triggered and started.

[0043] Threshold ΔU1 is set to below 80% of the normal phase voltage, and threshold ΔU2 is set to above 130% of the normal phase voltage. These are used to identify single-phase grounding fault characteristics in a neutral-point ungrounded system.

[0044] Step 2: Collect the three-phase bus voltage data (phase A, phase B, and phase C voltages) and zero-sequence voltage data of all relevant substations within the fault supply area through the power grid automation system. Normal operating voltages are as follows: Figure 2 As shown, the voltage characteristics of a single-phase ground fault are as follows: Figure 3 As shown.

[0045] Step 3: Call the established reference bus voltage library, automatically match and select the bus voltage data of the dual-power station or the upstream power station in the area with verified correct phase by bus name or grid topology as the reference phase reference; if automatic matching fails, output a prompt to manually select the reference phase reference.

[0046] The reference bus voltage library stores verified phase-correct substation buses and their topology association information; the automatic selection logic prioritizes the verified substation with the closest electrical connection distance or the most direct power supply path to the substation to be verified as the reference benchmark.

[0047] Step 4: Based on the characteristics of single-phase grounding faults in a neutral-point ungrounded system, analyze the voltage distribution characteristics of the reference base to determine the current fault phase.

[0048] Step 5: Compare the three-phase bus voltage data of the substation to be verified in the area with the fault phase and voltage value characteristics of the reference benchmark.

[0049] Step 6: Determine the phase correctness of the plant to be verified based on the comparison results: If the low voltage phase of the plant to be verified is consistent with the fault phase of the reference benchmark, and the voltage rise of the non-fault phase meets the theoretical characteristics, then the phase is preliminarily determined to be correct; otherwise, the phase is determined to be incorrect.

[0050] The voltage rise of the non-faulty phase conforming to the theoretical characteristics means that the voltage of the non-faulty phase rises to the level of the normal phase voltage. The voltage is approximately twice that of the three phases, and the three-phase line voltages remain symmetrical.

[0051] Step 7: Generate a phase verification report and a bus voltage comparison report. For substations that are determined to have phase errors, generate an abnormal alarm and push it to the relevant maintenance department for rectification.

[0052] The abnormal alarm includes the incorrect plant name, incorrect phase, voltage comparison data, and suggested corrective measures; if step 8 triggers manual processing, the alarm content will additionally include detailed information such as "voltage amplitude or zero-sequence voltage deviation exceeds the limit, manual review is required".

[0053] Step 8: For the substation bus voltage that was initially determined to be correct in phase in Step 6, further verify whether the differences between the phase voltage amplitude and zero-sequence voltage amplitude of this bus and the phase voltage amplitude and zero-sequence voltage amplitude of the reference base do not exceed the preset threshold ΔU. If all differences do not exceed ΔU, the substation bus voltage data will be automatically pushed to the reference bus voltage database to update the database. If any difference exceeds ΔU, a manual processing prompt will be generated, automatic data entry will be paused, and manual verification and processing will be performed before the substation bus voltage data is pushed to the reference bus voltage database to update the database.

[0054] Manual processing includes: the system generating a work order containing the name of the plant to be verified, the over-limit voltage component (such as zero-sequence voltage), the deviation value, and suggested inspection items (such as zero-sequence PT ratio, acquisition coefficient configuration, wiring inspection); after the manual completion of on-site verification or system parameter correction, a "verification passed" confirmation operation is performed in the system, and the system then performs the data entry operation.

[0055] Step 8 realizes the dynamic expansion and quality closed-loop control of the reference bus voltage library: through the dual mechanism of "automatic verification + manual review", it ensures that only plant data with three-phase voltage and zero-sequence voltage that are consistent with the reference height can enter the reference library, preventing erroneous data from polluting the reference library due to incorrect acquisition coefficients or equipment abnormalities.

[0056] The system for implementing the above-described method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid includes:

[0057] Monitoring module: Used to monitor the grid bus voltage in real time and identify single-phase grounding faults that meet the conditions ΔU1 and ΔU2.

[0058] Data acquisition module: Used to collect three-phase and zero-sequence voltage data of each power plant in the fault area through the power grid automation system.

[0059] Reference Management Module: Used to maintain the reference bus voltage library, execute the logic of automatically or manually selecting reference references, and receive requests to add new verification data to the library.

[0060] Analysis and comparison module: used to determine the faulty phase, compare the voltage characteristics of the substation to be verified with the reference reference, and determine the phase correctness.

[0061] Multidimensional verification and manual review module: used to calculate the difference between the plant to be verified and the reference benchmark in terms of three-phase voltage amplitude and zero-sequence voltage amplitude; if all differences meet the ΔU threshold, the entry instruction is automatically triggered; if any difference exceeds ΔU, a manual review work order is generated and the entry status is locked, waiting for manual confirmation instruction.

[0062] Report push module: Used to generate verification reports, comparison reports and anomaly alarms, and push them to relevant terminals.

[0063] The technical solution of this invention can be summarized as follows:

[0064] 1. Automatic Trigger: The system monitors in real time and automatically starts the verification process when it detects a typical single-phase grounding characteristic on a busbar, where "one phase voltage drops by ΔU1 and the voltage of the other two phases rises by ΔU2".

[0065] 2. Full data acquisition: Use an automated system (such as D5000) to collect three-phase voltage and zero-sequence voltage data of all relevant substations in the fault area.

[0066] 3. Intelligent Reference Selection: The system accesses the "Reference Bus Voltage Library". First, it attempts to automatically match a verified dual-power station or upstream station as a reference reference based on the bus name or topology relationship; if automatic matching fails, it prompts for manual intervention to select a reference.

[0067] 4. Fault phase identification: Analyze the reference data to determine the fault phase (i.e., the phase with the lowest voltage).

[0068] 5. Batch Comparison: Compare the data of the plant to be verified with the benchmark. If the low voltage phase of the plant to be verified is consistent with the benchmark, and the voltage rise of the non-faulty phases meets the requirements... If the phase is correct according to the theory characteristics, then the phase is preliminarily determined to be correct; otherwise, the determination is incorrect.

[0069] 6. Results processing: Generate a report, trigger alarms at faulty stations and push rectification work orders.

[0070] 7. Multidimensional verification and closed-loop data entry:

[0071] For substations initially deemed correct, the differences between the voltage amplitude of each phase and the reference benchmark, as well as the difference between the zero-sequence voltage amplitude and the reference benchmark, are calculated. Automatic data entry path: If all differences do not exceed the preset threshold ΔU, the substation's data quality is deemed acceptable, and its data (including three-phase and zero-sequence voltage) is automatically written into the "Reference Bus Voltage Library," making it the new benchmark for subsequent verification. Manual closed-loop path: If any difference exceeds ΔU (e.g., excessive zero-sequence voltage deviation), the system pauses automatic data entry and generates a manual processing prompt (including deviation details and suggested checks). After manual on-site verification, parameter correction (such as adjusting the acquisition coefficient), or confirmation of accuracy, the "Confirm Data Entry" operation is executed in the system, and the system pushes the data to the benchmark library.

[0072] Example 1:

[0073] First-time fault verification and automatic data entry for 35kV power grid

[0074] Scenario: A certain 35kV power grid area, such as Figure 4As shown, station A is a dual-power station (verified correctly), while stations B, C, and D are single-power stations (unverified). The system's preset thresholds are: ΔU1 = 10% of rated voltage, ΔU2 = 130% of rated voltage, and ΔU = 2% of rated voltage (including zero-sequence voltage tolerance).

[0075] Implementation process:

[0076] S1 Trigger: On a certain day, a phase A ground fault occurred on the 35kV busbar of station A. The system monitored that the phase A voltage dropped to 1kV (meeting ΔU1), while phases B and C rose to 35kV (meeting ΔU2), and automatically initiated verification.

[0077] S2 data acquisition: Collects data from four stations: A, B, C, and D.

[0078] Station A (benchmark): A=1, B=35, C=35, zero sequence=60.

[0079] Bilibili: A=35, B=1, C=35, Zero sequence=60.

[0080] Station C: A=1, B=35, C=35, Zero sequence=60.

[0081] Station D: A=1, B=35, C=35, Zero sequence=60.

[0082] S3 Reference Selection: The system queries the reference library and finds that station A is a verified dual-power station, and automatically selects station A as the reference reference.

[0083] S4 fault phase identification: Analyzing the data from station A, phase A has the lowest value, indicating that phase A is grounded.

[0084] S5-S6 comparison:

[0085] Stations C and D: Phase A is the lowest, characteristics are consistent -> preliminary judgment is correct. Station B: Phase B is the lowest, characteristics are inconsistent -> judgment is incorrect.

[0086] S7 Report: A report is generated, and Bilibili's alarm is pushed to operations and maintenance; Bilibili and D sites are awaiting database verification.

[0087] S8 Multidimensional Validation and Automatic Data Entry:

[0088] C-station verification: Three-phase difference: |1-1|=0, |35-35|=0, both <ΔU. Zero-sequence difference: |60-60|=0, <ΔU. Result: All conditions are met, and the system automatically writes the C-station data (including zero-sequence) into the baseline database.

[0089] D-station verification: Three-phase difference: |1-1|=0, |35-35|=0, both <ΔU. Zero-sequence difference: |60-60|=0, <ΔU. Result: All conditions are met, and the system automatically writes the D-station data into the benchmark database.

[0090] Result: Two new valid benchmark points, C and D, were added to the benchmark library, and the data quality was confirmed to be correct by automatic verification.

[0091] Example 2:

[0092] Cascaded verification and manual closed-loop processing (zero-order coefficient error scenario)

[0093] Scenario: such as Figure 5 As shown, the operating mode has been adjusted, with station C now powered by station Z (stations Z, E, and F are all single-power sources and have not been verified). At this point, the reference library already contains data for stations A, C, and D. Assuming the three-phase voltage wiring at station F is correct, but its zero-sequence voltage acquisition coefficient is configured incorrectly (e.g., it should actually be 100V / 3V, but is configured as 100V / 1.5V), the zero-sequence voltage reading is only half of the normal value.

[0094] Implementation process:

[0095] S1 Trigger: On a certain day, a phase A ground fault occurred in the power supply area of ​​station C. The system detected an abnormal voltage at station C and triggered verification.

[0096] S2 data collection: Collects data from stations C, Z, E, and F.

[0097] Station C (baseline): A=0.51, B=36, C=36, zero sequence=62.

[0098] Station Z: A=0.52, B=36, C=36, Zero sequence=62.

[0099] Station E: A=0.5, B=36.2, C=36, Zero sequence=62.

[0100] Station F (Abnormal): A=0.52, B=36, C=36.1, Zero Sequence=31 (caused by coefficient error).

[0101] S3 Reference Baseline Selection: The system automatically selects Station C (already included in Implementation Example 1) as the reference baseline.

[0102] S4-S6 comparison:

[0103] The reference station C is determined to have phase A grounding. Stations Z, E, and F: Phase A is the lowest, and the three-phase voltage characteristics are consistent with the reference station -> preliminary determination of correct phase. Note: At this time, station F is not determined to have a phase error because the three-phase voltages are phase matched.

[0104] S7 report: Stations Z, E, and F have been preliminarily determined to be correct. Proceed to S8 for verification.

[0105] S8 Multidimensional Verification and Manual Loop Closure:

[0106] Z-station and E-station verification: All three-phase and zero-sequence differences <ΔU-> are automatically entered into the database.

[0107] F-station verification: All three-phase differences are less than ΔU. Zero-sequence difference: |31-62|=31, far exceeding ΔU (2%). Result: Triggered the "Difference Exceeds Limit" condition. The system pauses automatic data entry and generates a work order prompt: "F-station zero-sequence voltage amplitude deviation exceeds limit (deviation 31kV), please manually check the acquisition coefficient or PT wiring." Manual handling: The maintenance personnel receive the work order, check the F-station automation system configuration, and find that the zero-sequence voltage acquisition coefficient configuration is incorrect. The maintenance personnel correct the coefficient configuration and re-acquire or simulate to verify that the data is normal. The maintenance personnel click "Confirm Correction, Apply for Data Entry" in the system. System response: The system receives the manual confirmation instruction and pushes the corrected voltage data of F-station (or marked as corrected) to the reference bus voltage database.

[0108] Results: Stations Z and E were automatically entered into the database; Station F was successfully entered into the database after manual correction, thus improving the baseline database and avoiding data contamination by errors.

[0109] This invention utilizes the voltage characteristics (one phase decreases by ΔU1, two phases increase by ΔU2) of a single-phase ground fault in a neutral-point ungrounded system to automatically trigger verification. It constructs a "reference bus voltage library," automatically matching verified dual-power sources or upstream power stations as reference benchmarks. It innovatively introduces a zero-sequence voltage amplitude verification mechanism, further verifying the amplitude differences of each phase voltage and zero-sequence voltage between the station to be verified and the reference station, based on an initial determination of phase consistency. If all differences are within a preset threshold ΔU, the data is automatically added to the reference library for dynamic updates; if any difference exceeds the limit, a manual closed-loop processing procedure is triggered, forcing manual verification and correction (such as adjusting acquisition coefficients and confirming wiring) before data can be added to the library. This invention, through a collaborative mechanism of "fault triggering + zero-sequence verification + human-machine closed-loop," achieves automation, high reliability, and continuous self-evolution of power grid phase verification and reference data.

Claims

1. A method for rapidly verifying the phase correctness of a neutral-point ungrounded power grid in batches, characterized in that, Includes the following steps: Step 1: Monitor the neutral point ungrounded system power grid in real time. When it is detected that the single-phase voltage of any bus at any station drops to the threshold ΔU1, and the voltage of the other two phases of the same bus rises to the threshold ΔU2, the phase verification process is automatically triggered and started. Step 2: Collect bus three-phase voltage data and zero-sequence voltage data of all relevant substations within the fault power supply area through the power grid automation system; Step 3: Call the established reference bus voltage library, automatically match and select the bus voltage data of the dual-power station or the upstream power station in the area with verified correct phase by bus name or grid topology as the reference phase reference; if automatic matching fails, output a prompt to manually select the reference phase reference. Step 4: Based on the characteristics of single-phase grounding faults in a neutral-point ungrounded system, analyze the voltage distribution characteristics of the reference base to determine the current fault phase; Step 5: Compare the three-phase bus voltage data of the substations to be verified within the area with the fault phase and voltage value characteristics of the reference benchmark; Step 6: Determine the phase correctness of the plant to be verified based on the comparison results: If the low voltage phase of the plant to be verified is consistent with the fault phase of the reference, and the voltage rise of the non-fault phase is consistent with the theoretical characteristics, then the phase is preliminarily determined to be correct. Otherwise, a phase error is determined. Step 7: Generate a phase verification report and a bus voltage comparison report. For substations that are determined to have phase errors, generate an abnormal alarm and push it to the relevant maintenance department for rectification. Step 8: For the substation bus voltage that was initially determined to be in the correct phase in Step 6, further verify whether the difference between the phase voltage amplitude and zero-sequence voltage amplitude of the bus and the phase voltage amplitude and zero-sequence voltage amplitude of the reference standard does not exceed the preset threshold ΔU. If all differences do not exceed ΔU, the bus voltage data of the plant will be automatically pushed to the reference bus voltage library to update the reference library. If any difference exceeds ΔU, a manual processing prompt will be generated, automatic data entry will be suspended, and manual verification and processing will be conducted before the bus voltage data of the plant is pushed to the reference bus voltage database to update the reference database.

2. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, In step 1, the threshold ΔU1 is set to below 80% of the normal phase voltage, and the threshold ΔU2 is set to above 130% of the normal phase voltage, which are used to identify the characteristics of single-phase grounding faults in a neutral-point ungrounded system.

3. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, In step 3, the reference bus voltage library stores the verified phase correct substation bus and its topology association information; the automatic selection logic prioritizes the verified substation with the closest electrical connection distance or the most direct power supply path to the substation to be verified as the reference benchmark.

4. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, In step 6, "the increase in voltage of the non-faulty phase conforms to the theoretical characteristics" means that the voltage of the non-faulty phase increases to the level of the normal phase voltage. The voltage is twice that of the three phases, and the three-phase line voltages remain symmetrical.

5. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, In step 7, the abnormal alarm includes the incorrect plant name, incorrect phase, voltage comparison data, and suggested corrective measures; if step 8 triggers manual processing, the alarm content will additionally include detailed information such as "voltage amplitude or zero-sequence voltage deviation exceeds the limit, manual review is required".

6. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, In step 8, manual processing includes: the system generating a work order containing the name of the plant to be verified, the over-limit voltage component, the deviation value, and the suggested inspection items; after the manual completion of on-site verification or system parameter correction, a "verification passed" confirmation operation is performed in the system, and the system then performs the warehousing operation.

7. The method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid according to claim 1, characterized in that, Step 8 enables the dynamic expansion and quality closed-loop control of the reference bus voltage library.

8. A system for implementing the method for rapidly batch verifying the phase correctness of a neutral-point ungrounded system power grid as described in any one of claims 1-7, characterized in that, include: Monitoring module: Used to monitor the grid bus voltage in real time and identify single-phase grounding faults that meet the conditions ΔU1 and ΔU2; Data acquisition module: used to collect three-phase and zero-sequence voltage data of each substation in the fault area through the power grid automation system; Reference Management Module: Used to maintain the reference bus voltage library, execute the logic for automatic or manual selection of reference references, and receive requests to add new verification data to the library; Analysis and comparison module: used to determine the faulty phase, compare the voltage characteristics of the plant to be verified with the reference reference, and determine the phase correctness; Multidimensional verification and manual review module: used to calculate the difference between the plant to be verified and the reference benchmark in terms of three-phase voltage amplitude and zero-sequence voltage amplitude; if all differences meet the ΔU threshold, the entry instruction is automatically triggered; if any difference exceeds ΔU, a manual review work order is generated and the entry status is locked, waiting for manual confirmation instruction. Report push module: Used to generate verification reports, comparison reports and anomaly alarms, and push them to relevant terminals.

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