Method for verifying relay protection setting value applicability through invisible fault diagnosis, electronic equipment and storage medium

Abstract

The invention discloses a method and software for verifying relay protection setting value applicability through invisible fault diagnosis, and relates to the technical field of line fault analysis, and the method comprises the following steps: 1, collecting fault data, and constructing a fault data set C; 2, current distribution conditions of the main line and the branch lines are obtained; step 3, fault simulation; actual fault point data of the fault line is input into the setting calculation platform, and fault simulation is carried out; step 4, comparing and analyzing data; performing comparative analysis on the actual fault current distribution condition and the distribution condition of the analog calculation to obtain a preliminary comparison result; step 5, fault reasons are eliminated; a relay protection fault reason database is established, the preliminary comparison results obtained in the fourth step are compared and eliminated one by one in the established fault reason database, and finally fault reason analysis is obtained; step 6, performing backstepping verification; and carrying out back-stepping verification on the fault reason obtained in the step 5 according to an inverse logic mode. Difference points are found through calculation and analysis of all the steps, hidden problems of faults are diagnosed, and therefore the correctness and applicability of setting calculation are effectively verified.

Description

Technical Field

[0001] The present invention relates to the technical field of equipment relay protection fault analysis, and specifically to a method, electronic equipment and storage medium for verifying the applicability of relay protection settings through invisible fault research; the applicability and accuracy of relay protection settings are verified through fault analysis and actual fault simulation calculation. Background Art

[0002] At present, the Northwest Power Grid is in the period of green and low-carbon energy transformation, with a high proportion of new energy and a high proportion of power electronic equipment, and the "double high" characteristics are obvious. The construction of new power systems has entered an "acceleration period", and the operating characteristics of the power grid have undergone profound changes. New situations have emerged in traditional stability problems and new risks in the power grid continue to emerge. The existing level of cognition, operation prevention and control, adjustment means, institutional mechanisms, and support and guarantee are not adapted.

[0003] The structure of the Northwest Power Grid is relatively complex, with a large number of electrical ring networks, electromagnetic ring networks, parallel double-circuit lines and other complex modes. The setting calculation itself has a lot of problems such as incompatibility and insufficient remote backup sensitivity. Coupled with uncertain external factors such as zero-sequence mutual inductance, the risk of relay protection misoperation and refusal to operate will be greatly increased. At the same time, under the new power system, the impact of the "double high" characteristics on the relay protection setting calculation is still under study, and the results are not clear. The risk of "missetting" of relay protection has increased significantly! At present, the relay protection setting calculation only relies on the relay protection setting calculation platform, and lacks effective verification means to prevent "missetting".

[0004] Therefore, we propose a method to study hidden faults and verify the applicability of relay protection settings in order to solve the problems raised above.

[0005] In the prior art, China's authorized patent announcement number: CN 118884072 A, discloses a fault diagnosis method for a relay protection device, including obtaining an unconventional historical fault data set S1 and a conventional historical fault data set S2; using S2 to initially train a relay protection device fault diagnosis model; preprocessing the abnormal state data in S1 to obtain a data set S3; using the initially trained model to filter S3 to obtain a filtered unconventional historical fault data set S3'; randomly modifying the historical operating state data in S2 to obtain a data set S4; using the data sets S1, S2, S3' and S4 to train a confrontation network model GAN; passing the operating state data X1 in S1 into the generator of the trained GAN to generate data X5, corresponding the fault diagnosis in the data set S1 and the generated data X5 to construct the data set S5; further training the relay protection device fault diagnosis model with the obtained data sets S5 and S2 to obtain the final relay protection device fault diagnosis model. Summary of the invention

[0006] The technical problem to be solved by the present invention is to address the deficiencies in the prior art and disclose a method, electronic device and storage medium for verifying the applicability of relay protection settings through invisible fault diagnosis, which verifies the applicability and accuracy of relay protection settings through fault analysis and actual fault simulation calculation.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: Step 1: Collect fault data; obtain the voltage and current waveforms of the main line equipment under the fault state, and construct a fault data set C;

[0008] Step 2: Obtain current distribution; check the current distribution of other power branches in the fault data set C;

[0009] Step 3: Fault simulation: Input the actual fault point data of the fault line into the setting calculation platform, simulate the fault, and record the current distribution of each power branch during the simulation;

[0010] Step 4: data comparison and analysis; compare and analyze the actual fault current distribution with the simulated distribution to obtain a preliminary comparison result. If the preliminary comparison result is abnormal, further analyze the actual fault current distribution with the simulated distribution.

[0011] Step 5: Eliminate the cause of the fault; establish a relay protection fault cause database, compare and eliminate the preliminary comparison results obtained in step 4 one by one in the established fault cause database, and finally obtain a fault cause analysis. If the preliminary comparison result does not meet any item in the fault cause database, it is automatically added to the fault cause database;

[0012] Step 6: reverse verification; reverse the fault cause obtained in step 5 in a reverse logic manner.

[0013] Further:

[0014] The simulated fault process in step 3 is as follows:

[0015] Step 3.1: Perform drawing operation in the setting calculation platform, set the line and set the line parameters in the drawing;

[0016] Step 3.2: Get the theoretical value by setting two cases: parallel lines and lines erected on the same pole;

[0017] Step 3.3: Calculate the parallel lines and the lines erected on the same pole on the setting calculation platform to obtain calculation results;

[0018] Step 3.4: Based on step 3.3, input the mutual inductance impedance value to simulate the fault condition.

[0019] Further:

[0020] The process of reverse verification in step 6 is as follows:

[0021] Step 6.1: Based on the fault cause analysis obtained in step 5, the actual data of the actual fault recording of the fault line A and the fault line B are compared with the simulated fault data of the setting calculation platform;

[0022] Step 6.2: Compare and analyze the actual conditions of the faulty line A and the faulty line B.

[0023] Step 6.3: Use the setting platform to simulate the fault line, deduce the fault cause by simulating the fault situation, and then input the inversely derived fault data into the setting calculation platform to finally obtain the calculation result. The calculation result is consistent with the actual data, proving that the inference is correct;

[0024] Step 6.4: To further verify the effectiveness of the measured data and the inverse method, the staff measured the fault point and compared the measured values ​​with the values ​​obtained by the inverse method.

[0025] Further:

[0026] The fault cause database includes: line parameter errors, line protection current transformer ratio errors, line secondary circuit wiring errors, neutral point grounding conditions of the main transformer in the network are inconsistent with the actual situation, main transformer equipment parameter errors, calculation methods of the setting calculation platform of the relay protection, parameter settings, system settings, maintenance mode settings errors, correctness of the system interface impedance, and grounding resistance errors of the grounding grid of the Imperial Palace Substation.

[0027] Further:

[0028] The device comprises:

[0029] a processor configured to execute computer executable instructions;

[0030] A memory stores one or more computer executable instructions.

[0031] Further:

[0032] The processor is configured to execute computer executable instructions. When the computer executable instructions are executed by the processor, the steps of the method for realizing relay protection fault diagnosis and processing based on multi-source information described in any one of claims 1 to 4 are implemented.

[0033] Further:

[0034] The step 1 is to collect fault data through a fault recorder.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The method of the present invention performs fault simulation on a setting platform, then performs actual calculation on the fault point, and then performs reverse calculation. The two results are compared to verify the accuracy of the data. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the process of the present invention;

[0038] Figure 2 This is a schematic diagram of actual fault recording of the present invention;

[0039] Figure 3 It is a schematic diagram of recording the fault waveform of the line parallel to the fault line of the present invention;

[0040] Figure 4 Simulate the line current distribution table for this fault;

[0041] Figure 5 This is the current distribution table for each branch of the fault simulation line. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] like Figure 1 As shown, it shows a schematic flow chart of the method of the present invention, and the process is as follows:

[0044] Step 1: Collect fault data; obtain the voltage and current waveforms of the main line equipment under the fault state, and construct the fault data set C;

[0045] Step 2: Obtain current distribution; check the current distribution of other power branches in the fault data set C;

[0046] Step 3: Fault simulation: Input the actual fault point data of the fault line into the setting calculation platform, simulate the fault, and record the current distribution of each power branch during the simulation;

[0047] Step 4: data comparison and analysis; compare and analyze the actual fault current distribution with the simulated distribution to obtain a preliminary comparison result. If the preliminary comparison result is abnormal, further analyze the actual fault current distribution with the simulated distribution.

[0048] Step 5: Eliminate the cause of the fault; establish a relay protection fault cause database, compare and eliminate the preliminary comparison results obtained in step 4 one by one in the established fault cause database, and finally obtain a fault cause analysis. If the preliminary comparison result does not meet any item in the fault cause database, it is automatically added to the fault cause database;

[0049] Step 6: reverse verification; reverse the fault cause obtained in step 5 in a reverse logic manner.

[0050] Specific implementation example: In the actual project, the 110Kv Huanggu and Huangge wirings failed, and the protection function worked correctly. Now the fault analysis is carried out:

[0051] Step 1: Collect fault recording information, check the voltage and current waveforms of the faulty equipment, and analyze whether they are consistent with the fault situation; collect the fault recording diagram and the timing of the protection device, and two conclusions can be confirmed: the cause of the 110Kv Huanggu wiring fault is clear, and the protection operates correctly; the 110Kv Huangge line tripped due to the Huanggu wiring fault, which is indeed a false operation of the fault-free protection.

[0052] like Figure 2 and 3 As shown, it shows the schematic diagram of the fault recording of the 110Kv Huanggu line and Huangge line;

[0053] Step 2: Check the current distribution of other power branches in the fault recording, analyze whether there is any abnormality and record the data; Figure 4 As shown, it shows the zero-sequence current distribution of each grounding branch when the 110Kv Huanggu pull-wire fails.

[0054] Step 3: According to the actual fault point, simulate the fault in the setting calculation platform and record the data, such as Figure 5 As shown, it shows the zero-sequence current distribution of each grounding branch when the 110Kv Huangge tie-line fails;

[0055] Step 4: Compare and analyze the actual fault current distribution with the distribution calculated by simulation to see if there is any abnormality. If there is any abnormality, further analyze it.

[0056] Step 5: Eliminate the factors that affect the abnormal increase of zero-sequence current of Huangge line; eliminate them one by one: 1. Suspect that the line parameters of 110 kV Huangge line are wrong; 2. Suspect that the ratio of CT protection of Huangge line is wrong; 3. Suspect that the wiring of secondary circuit of Huangge line is wrong; 4. Suspect that the neutral point grounding of main transformer in the network is inconsistent with the actual situation or the equipment parameters are wrong; 5. Suspect that the calculation method, parameter setting, system setting and maintenance mode setting of relay protection setting calculation platform are wrong; 6. Verify the correctness of system boundary impedance; 7. Suspect that the grounding resistance of Huanggong transformer grounding network does not meet the countermeasure requirements; After the above one-by-one verification and on-site investigation, the above doubts are correct. After another on-site connection, it was learned that Huangge line and Huanggu line are parallel, and the zero-sequence mutual inductance is suspected.

[0057] Step 6: Reverse verification; verify that the zero-sequence mutual inductance impedance is the cause of this line fault.

[0058] According to conventional methods, we can only verify the inference by measuring the zero-sequence mutual inductance of the two lines after power outage to find out that the zero-sequence mutual inductance may be the cause of the malfunction of the Huangge line. Otherwise, we cannot quickly and effectively prove that our inference is correct. However, through unremitting efforts and a strong desire for knowledge, we finally found a way to verify our inference without actual measurement. The specific steps are as follows:

[0059] Step 6.1: To prove the influence of zero-sequence mutual inductance, we first check if the actual zero-sequence distribution is consistent with the theoretical calculation value of the setting calculation platform if there is no influence of zero-sequence mutual inductance according to the anti-logical way of thinking. To further prove it, the staff retrieved the fault recording file of Huanggu Line. Both Huangyou Line and Huanggu Pull Line are radioactive terminal ungrounded lines. The Huangyou Line and Huangge Line are installed in opposite paths, so it is impossible for zero-sequence mutual inductance to exist.

[0060] Step 6.2: Through comparative analysis of the zero-sequence current distribution when the Huangyou line and the Huanggu line failed, it was found that when the Huangyou line failed, the zero-sequence current flowing through the Huangge line was basically consistent with the calculated value of the setting calculation platform, and the fault current of the Huangyou line was basically similar to the fault current of the Huanggu line, and the zero-sequence current flowing through the Huangge line was more obvious, which was enough to prove that only when the Huanggu line failed, the zero-sequence current flowing through the Huangge line became abnormally large, which means that there was indeed a mutual influence between the Huanggu line and the Huangge line. At the same time, it was also found that when the Huangyou line failed, the zero-sequence current flowing through the Huangyuan line became abnormally large, and when the Huanggu line failed, the zero-sequence current flowing through the Huangyuan line was basically consistent with the theoretical calculated value. After verification with the site, the Huangyuan line and the Huangyou line were also laid in parallel throughout the entire line, which once again fully proved that our inference was correct and that there was indeed a zero-sequence mutual inductance impedance between the Huanggu line and the Huangge line.

[0061] Step 6.3: In order to further prove the influence of zero-sequence mutual inductance impedance on the setting calculation, we simulated the fault of Huanggu Pulling Line and Huangyou Line from the relay protection setting platform, and simulated the situation consistent with the zero-sequence distribution during the fault, and then deduced the value of zero-sequence mutual inductance impedance. The nominal value of the zero-sequence mutual inductance impedance between Huanggu Pulling Line and Huangge Line is 0.6426×13.225=8.498 ohms. Then the deduced zero-sequence mutual inductance impedance is input into the setting calculation platform, and the calculated zero-sequence current distribution is indeed consistent with the actual current flowing through the fault recording, which is enough to prove that our inference is absolutely correct.

[0062] Step 6.4: In order to further promote the actual measurement of zero-sequence mutual inductance impedance and further verify the effectiveness of our reverse deduction method, the staff simultaneously shut down the Huangge line and the Huanggu line to conduct parameter measurement work. The measured zero-sequence mutual inductance impedance was 8.3648 ohms, and the inferred zero-sequence mutual inductance impedance was 8.498 ohms. The test results were almost the same as the reverse deduction results, and the conclusions were completely consistent.

[0063] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for verifying the applicability of relay protection settings by invisible fault diagnosis. Features: The following steps are involved: Step 1: Collect fault data; obtain the voltage and current waveforms of the main line equipment under the fault state, and construct the fault data set C; Step 2: Obtain current distribution; check the current distribution of other power branches in the fault data set C; Step 3: Fault simulation: Input the actual fault point data of the fault line into the setting calculation platform, perform fault simulation, and record the current distribution of each power branch during the simulation; Step 4: Data comparison and analysis; Compare and analyze the actual fault current distribution with the distribution of the simulated calculation to obtain a preliminary comparison result. If the preliminary comparison result is abnormal, further analyze the actual fault current distribution with the simulated calculation; Step 5: Eliminate the cause of the fault; establish a relay protection fault cause database, compare and eliminate the preliminary comparison results obtained in step 4 one by one in the established fault cause database, and finally obtain a fault cause analysis. If the preliminary comparison result does not meet any item in the fault cause database, it is automatically added to the fault cause database; Step 6: reverse verification; reverse the fault cause obtained in step 5 in a reverse logic manner.

2. According to claim 1, a method for verifying the applicability of relay protection setting values ​​by invisible fault diagnosis, Features: The fault simulation process in step 3 is as follows: Step 3.1: Perform drawing operation in the setting calculation platform, set the line and set the line parameters in the drawing; Step 3.2: Get the theoretical value by setting two cases: parallel lines and lines erected on the same pole; Step 3.3: Calculate the parallel lines and the lines erected on the same pole on the setting calculation platform to obtain calculation results; Step 3.4: Based on step 3.3, input the mutual inductance impedance value to simulate the fault condition.

3. According to claim 1, a method for verifying the applicability of relay protection setting values ​​by invisible fault diagnosis, Features: The process of reverse verification in step 6 is as follows: Step 6.1: Based on the fault cause analysis obtained in step 5, the actual data of the actual fault recording of the fault line A and the fault line B are compared with the simulated fault data of the setting calculation platform; Step 6.2: Compare and analyze the actual conditions of the faulty line A and the faulty line B. Step 6.3: Use the setting platform to simulate the fault line, deduce the fault cause by simulating the fault situation, and then input the inversely derived fault data into the setting calculation platform to finally obtain the calculation result. The calculation result is consistent with the actual data, proving that the inference is correct; Step 6.4: To further verify the effectiveness of the measured data and the inverse method, the staff measured the fault point and compared the measured values ​​with the values ​​obtained by the inverse method.

4. According to claim 1, a method for verifying the applicability of relay protection setting values ​​by diagnosing invisible faults, Features: The fault cause database includes: line parameter errors, line protection current transformer ratio errors, line secondary circuit wiring errors, main transformer neutral point grounding conditions in the network are inconsistent with the actual situation, main transformer equipment parameter errors, calculation method of the setting calculation platform of the relay protection, parameter settings, system settings, maintenance mode setting errors, correctness of system interface impedance, and grounding resistance errors of the substation grounding network.

5. According to claim 1, a method for verifying the applicability of relay protection setting values ​​by diagnosing invisible faults, Features: The step 1 is to collect fault data through a fault recorder.

6. An electronic device, characterized in that: including processor and storage medium; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1 to 5.

7. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the program is executed by a processor, the steps of any method of any of claims 1 to 5 are implemented.

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