Air clearance computation method and system for shield ball fitting, device, and medium

Abstract

An air clearance computation method and system for a shield ball fitting, a device, and a medium, relating to the technical field of fittings. The air clearance computation method for a shield ball fitting comprises: respectively computing voltages corresponding to overlapping of boundaries of a shield ball fitting at a plurality of preset altitudes, and generating corresponding boundary voltages; according to the respective boundary voltages, performing positive switching impulse discharge tests, and generating discharge voltage test values; using the discharge voltage test values to perform model construction, performing discharge voltage computation, and generating an intermediate shield ball fitting discharge voltage computation model and discharge voltage computation values; on the basis of an error between each discharge voltage computation value and the corresponding discharge voltage test value, updating the intermediate shield ball fitting discharge voltage computation model, and generating a target shield ball fitting discharge voltage computation model; and by means of the target shield ball fitting discharge voltage computation model, acquiring an air clearance corresponding to the shield ball fitting at a target altitude. On the basis of switching impulse discharge tests performed at a plurality of altitudes, a more accurate air clearance computation result can be obtained.

Description

A method, system, device and medium for calculating air clearance of shielded ball fittings

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 24, 2023, with application number 202311592282.4 and invention name “A method, system, device and medium for calculating the air clearance of shielded ball hardware”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of hardware, and in particular to a method, system, equipment and medium for calculating the air clearance of shielding ball hardware. Background Art

[0003] Converter valves are critical devices for DC power transmission and conversion. Shielding ball fittings are widely used within converter valves to reduce electromagnetic interference and improve system stability. These fittings, by strategically placing clearances between the valve and the surrounding environment, create a shielding effect, reducing interference from electric and magnetic fields and ensuring safe and reliable operation of the converter valve. However, to ensure the effectiveness of these fittings, maintaining a clear air distance from the surrounding environment is crucial.

[0004] Air clearance refers to the minimum vertical gap between the shielding ball fitting and surrounding metal surfaces (such as cutting boards and partitions). Accurate calculation of air clearance can help avoid arcing, breakdown, and other faults, protect converter valve equipment, and improve system performance.

[0005] Current methods for calculating the air clearance between shielding ball fittings in converter valves have several problems and limitations. Existing methods are typically based on empirical formulas, simplified models, or theoretical assumptions, failing to fully account for the complexity and diversity of real-world engineering environments, resulting in low calculation accuracy.

[0006] Summary of the Invention

[0007] The present invention provides a method, system, device and medium for calculating the air clearance of shielded ball hardware, which solves the technical problem that the existing methods for calculating the air clearance of shielded ball hardware are usually based on empirical formulas, simplified models or theoretical assumptions, and cannot fully consider the complexity and diversity of the actual engineering environment, thereby resulting in low accuracy of the calculation results.

[0008] The present invention provides a method for calculating the air clearance of shielding ball hardware, comprising:

[0009] Acquiring structural data of the shielding ball hardware, using the structural data to respectively calculate voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, and generating boundary voltages corresponding to the preset altitudes;

[0010] Performing positive polarity operation impulse discharge tests according to the boundary voltage to generate discharge voltage test values ​​corresponding to the preset altitude;

[0011] The discharge voltage test value is used to construct a model and perform discharge voltage calculation to generate a discharge voltage calculation model for the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to the preset altitude;

[0012] updating the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value to generate a target shielding ball hardware discharge voltage calculation model;

[0013] The air clearance at the target altitude corresponding to the shielding ball hardware is obtained through the target shielding ball hardware discharge voltage calculation model, and the air clearance corresponding to the shielding ball hardware is generated.

[0014] Optionally, the step of using the structural data to respectively calculate the voltages corresponding to the overlapped boundaries of the shielding ball fittings at multiple preset altitudes to generate the boundary voltages corresponding to the preset altitudes includes:

[0015] Using multi-physics field simulation software to construct a model according to the structural data to generate a ball-plate model corresponding to the shielding ball hardware;

[0016] Performing spherical electrode voltage simulations at multiple preset altitudes on the spherical-plate model according to preset voltage application requirements, and generating electrode change data corresponding to the preset altitudes;

[0017] Substituting the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula respectively to perform boundary calculations to generate upper boundary data and lower boundary data corresponding to the electrode change data;

[0018] The preset upper boundary condition formula is:

[0019] Where d1 represents the electrode surface; d2 represents the distance between the upper boundary and the electrode surface; N crit represents the critical charge number required to form a streamer, which is 0.55×10 -8 ;α is the ionization coefficient; η is the adsorption coefficient; e represents the natural constant, which is 2.718;

[0020] The preset lower boundary condition formula is: α=η;

[0021] Where α is the ionization coefficient; η is the adsorption coefficient; the values ​​of α and η are related to the spatial electric field strength and the relative density of air. The calculation formula for the spatial electric field strength is:

[0022] Where α is the ionization coefficient; η is the adsorption coefficient; E is the electric field strength in space, kV / cm; e represents the natural constant, which is 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0023] Where δ is the relative density of air; t is the ambient temperature at each altitude, in °C; p is the atmospheric pressure at each altitude; p0 is the standard atmospheric pressure, which is 101 kPa.

[0024] When the upper boundary data is equal to the lower boundary data, the voltage value corresponding to the ball-plate model at the current moment is used as the boundary voltage corresponding to the preset altitude.

[0025] Optionally, the step of performing a positive polarity operation impulse discharge test according to the boundary voltage to generate a discharge voltage test value corresponding to the preset altitude includes:

[0026] simulating the test device according to the structural data to generate the test device;

[0027] According to the boundary voltage corresponding to the preset altitude, a positive polarity operating impulse voltage waveform is used to perform an impulse test of multiple preset gap distances on the test device to generate a discharge voltage test value corresponding to the preset altitude.

[0028] Optionally, the step of using the discharge voltage test value to construct a model and perform discharge voltage calculation to generate a discharge voltage calculation model for the intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude includes:

[0029] Dividing the discharge voltage test values ​​corresponding to all the preset altitudes according to the same gap spacing to generate multiple model training sets;

[0030] The model training set is used to input the initial shielding ball hardware discharge voltage calculation model to perform parameter calculation and determine the model parameters;

[0031] The calculation model of the discharge voltage of the initial shielding ball hardware is:

[0032] Where U 50 represents the discharge voltage test value; U0 represents the rod-plate positive polarity switching impulse discharge voltage at an altitude of 0m, in kV; H represents the altitude, in meters; e represents a natural constant, which is 2.718; k represents the shape factor, which is determined by the size of the shielding ball and the gap structure; A and B represent altitude factors, and k, A, and B are dimensionless.

[0033] Using the model parameters to update the initial shielding ball hardware discharge voltage calculation model to generate an intermediate shielding ball hardware discharge voltage calculation model;

[0034] The preset altitude is substituted into the middle shielding ball hardware discharge voltage calculation model for calculation to generate a discharge voltage calculation value corresponding to the preset altitude.

[0035] Optionally, the step of updating the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value to generate the target shielding ball hardware discharge voltage calculation model includes:

[0036] Calculate the error between the calculated discharge voltage value and the corresponding test discharge voltage value using a preset error calculation formula to generate a mean absolute error percentage;

[0037] The preset error calculation formula is:

[0038] Where Y represents the mean absolute error percentage; n represents the number of test altitude points; i is 1, 2, ..., n; U i Indicates the discharge voltage test value at the i-th altitude point; U' i represents the calculated value of discharge voltage at the i-th altitude point;

[0039] The intermediate shielding ball hardware discharge voltage calculation model is updated according to the mean absolute error percentage and a preset threshold value to generate a target shielding ball hardware discharge voltage calculation model.

[0040] Optionally, the step of updating the intermediate shielding ball hardware discharge voltage calculation model according to the mean absolute error percentage and a preset threshold to generate a target shielding ball hardware discharge voltage calculation model includes:

[0041] Determining whether the mean absolute error percentage is greater than a preset threshold;

[0042] If yes, then calculating the average value between the calculated discharge voltage value and the test discharge voltage value corresponding to the mean absolute error percentage to generate an adjustment parameter;

[0043] Using the adjustment parameters to modify the model parameters of the intermediate shielding ball hardware discharge voltage calculation model to generate a target shielding ball hardware discharge voltage calculation model;

[0044] If not, the middle shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model.

[0045] Optionally, the step of obtaining the air clearance at the target altitude corresponding to the shielding ball hardware by using the target shielding ball hardware discharge voltage calculation model and generating the air clearance corresponding to the shielding ball hardware includes:

[0046] The discharge voltage calculation model of the target shielding ball hardware is used to obtain the discharge voltage of the shielding ball hardware at different gap distances at the target altitude, and generate multiple shielding ball hardware discharge voltages;

[0047] Using the shielding ball hardware discharge voltage to perform nonlinear function fitting to generate a discharge voltage change relationship;

[0048] Obtaining the discharge voltage of the equipment end fittings in the valve hall of the converter station;

[0049] Substitute the discharge voltage of the equipment end fitting into the discharge voltage variation equation to calculate the air clearance corresponding to the shielding ball fitting.

[0050] The present invention also provides a shielding ball hardware air clearance calculation system, comprising:

[0051] a boundary voltage generating module, configured to obtain structural data of the shielding ball hardware, and use the structural data to respectively calculate the voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, thereby generating boundary voltages corresponding to the preset altitudes;

[0052] a discharge voltage test value generating module, configured to perform a positive polarity operation impulse discharge test according to the boundary voltage and generate a discharge voltage test value corresponding to the preset altitude;

[0053] a discharge voltage calculation value generation module, configured to use the discharge voltage test value to construct a model and perform discharge voltage calculation, thereby generating a discharge voltage calculation model for the intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude;

[0054] a calculation model generation module, configured to update the discharge voltage calculation model of the intermediate shielding ball hardware according to an error between the discharge voltage calculation value and the corresponding discharge voltage test value, and generate a target shielding ball hardware discharge voltage calculation model;

[0055] The air clearance generation module is used to obtain the air clearance at the target altitude corresponding to the shielding ball hardware through the target shielding ball hardware discharge voltage calculation model, and generate the air clearance corresponding to the shielding ball hardware.

[0056] The present invention also provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of implementing any of the above-mentioned methods for calculating the air clearance of shielded ball hardware.

[0057] The present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements any of the above-mentioned methods for calculating the air clearance of shielded ball hardware.

[0058] It can be seen from the above technical solutions that the present invention has the following advantages:

[0059] The present invention obtains structural data of shielding ball hardware and uses this data to calculate the voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, generating boundary voltages corresponding to the preset altitudes. Positive polarity operating impulse discharge tests are then conducted based on the boundary voltages to generate discharge voltage test values ​​corresponding to the preset altitudes. Model construction and discharge voltage calculations are performed using the discharge voltage test values ​​to generate a discharge voltage calculation model for an intermediate shielding ball hardware and a discharge voltage calculation value corresponding to the preset altitudes. The discharge voltage calculation model for the intermediate shielding ball hardware is updated based on the error between the discharge voltage calculation value and the corresponding discharge voltage test value to generate a target shielding ball hardware discharge voltage calculation model. The target shielding ball hardware discharge voltage calculation model is used to obtain the air clearance corresponding to the shielding ball hardware at the target altitude, generating the corresponding air clearance. This method solves the technical problem that existing shielding ball hardware air clearance calculation methods are typically based on empirical formulas, simplified models, or theoretical assumptions, and fail to fully consider the complexity and diversity of real-world engineering environments, resulting in low accuracy in the calculation results. Based on operating impulse discharge tests at multiple altitudes, the calculation of the air clearance of the shielding ball hardware is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0061] FIG1 is a flowchart of a method for calculating the air clearance of shielding ball hardware provided in a first embodiment of the present invention;

[0062] FIG2 is a flowchart of a method for calculating the air clearance of shielding ball hardware provided in a second embodiment of the present invention;

[0063] FIG3 is a layout diagram of a positive polarity standard operating impulse discharge test provided in Example 2 of the present invention;

[0064] 4 is a characteristic curve diagram of the 50% operating impulse discharge voltage U50%-air clearance d of a 1.1m shielded spherical fitting at an altitude of 3800m provided in the second embodiment of the present invention;

[0065] 5 is a characteristic curve diagram of the 50% operating impulse discharge voltage U50%-air clearance d of a 1.1m shielded spherical fitting at an altitude of 4500m provided in the second embodiment of the present invention;

[0066] FIG6 is a structural block diagram of a shielding ball fitting air clearance calculation system provided in a third embodiment of the present invention.

[0067] The reference numerals in FIG3 are: 1. impulse voltage generator; 2. bellows; 3. insulator; 4. crane; 5. three-hole equalizing ball; 6. test piece; 7. grounding pile. DETAILED DESCRIPTION

[0068] Embodiments of the present invention provide a method, system, device, and medium for calculating the air clearance of shielded ball hardware, which are used to solve the technical problem that existing methods for calculating the air clearance of shielded ball hardware are usually based on empirical formulas, simplified models, or theoretical assumptions, and cannot fully consider the complexity and diversity of the actual engineering environment, resulting in low accuracy of the calculation results.

[0069] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below 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 making creative work are within the scope of protection of the present invention.

[0070] Please refer to FIG1 , which is a flowchart of a method for calculating the air clearance of shielding ball fittings provided in a first embodiment of the present invention.

[0071] A method for calculating the air clearance of shielding ball hardware provided in Example 1 of the present invention includes:

[0072] Step 101: Acquire structural data of the shielding ball hardware, use the structural data to calculate the voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes.

[0073] The preset altitude refers to the altitude set in advance for the test. The preset altitude is usually set to 0m, 1000m, 2000m, 3000m, 4000m, and 5000m.

[0074] In an embodiment of the present invention, the structural data of the shielding ball hardware is obtained, and a model is constructed according to the structural data using multi-physics field simulation software to generate a ball-plate model corresponding to the shielding ball hardware. The upper and lower boundaries of the critical volume of the shielding ball hardware at each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m) are respectively calculated to coincide with each other, that is, the boundary voltage when the critical volume is a point. Specifically, according to the preset voltage application requirements, the ball electrode voltage simulation at multiple preset altitudes is performed on the ball-plate model to generate electrode change data corresponding to the preset altitude. The electrode change data is respectively substituted into the preset upper boundary condition formula and the preset lower boundary condition formula for boundary calculation to generate upper boundary data and lower boundary data corresponding to the electrode change data. When the upper boundary data is equal to the lower boundary data, the voltage value corresponding to the ball-plate model at the current moment is used as the boundary voltage corresponding to the preset altitude.

[0075] Step 102: Perform a positive polarity operation impulse discharge test according to the boundary voltage to generate a discharge voltage test value corresponding to a preset altitude.

[0076] In an embodiment of the present invention, a test device is simulated according to the structural data to generate a test device. A positive polarity operating impulse voltage waveform is used to perform impulse tests on the test device at multiple preset gap distances according to the boundary voltage corresponding to the preset altitude, thereby generating discharge voltage test values ​​corresponding to the preset altitudes. Specifically, positive polarity operating impulse discharge tests are performed on the ball-plate gap at different preset gap distances (1.00m, 3.00m, 5.00m, 7.00m, and 9.00m) at each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, and 5000m), thereby obtaining 50% operating impulse discharge voltage test values, i.e., discharge voltage test values, corresponding to each preset altitude.

[0077] Step 103 : Use the discharge voltage test value to construct a model and perform discharge voltage calculation to generate a discharge voltage calculation model for the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to a preset altitude.

[0078] In an embodiment of the present invention, a shielding ball hardware discharge voltage calculation model is established for different preset altitudes at the same gap distance. The 50% operating impulse discharge voltage test values ​​of the shielding ball hardware at different preset altitudes are substituted into the model to determine the model parameters. Specifically, the discharge voltage test values ​​corresponding to all preset altitudes are divided according to the same gap spacing to generate multiple model training sets. The model training sets are respectively input into the initial shielding ball hardware discharge voltage calculation model for parameter calculation to determine the model parameters. The initial shielding ball hardware discharge voltage calculation model is updated using the model parameters to generate an intermediate shielding ball hardware discharge voltage calculation model. Each preset altitude is substituted into the intermediate shielding ball hardware discharge voltage calculation model for calculation to obtain the calculated value of the 50% operating impulse discharge voltage of the shielding ball hardware at each preset altitude, i.e., the discharge voltage calculated value.

[0079] Step 104 : updating the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and generating a target shielding ball hardware discharge voltage calculation model.

[0080] In this embodiment of the present invention, a preset error calculation formula is used to calculate the error between the calculated discharge voltage value and the corresponding test discharge voltage value, generating a mean absolute error percentage. Based on the mean absolute error percentage and a preset threshold, the intermediate shielding ball hardware discharge voltage calculation model is updated to generate the target shielding ball hardware discharge voltage calculation model.

[0081] Step 105: Obtain the air clearance at the target altitude corresponding to the shielding ball hardware through the target shielding ball hardware discharge voltage calculation model, and generate the air clearance corresponding to the shielding ball hardware.

[0082] In this embodiment of the present invention, a target shielding ball hardware discharge voltage calculation model is used to obtain the discharge voltage of the shielding ball hardware at different clearance distances at the target altitude, generating multiple shielding ball hardware discharge voltages. A nonlinear function fitting is performed using the shielding ball hardware discharge voltage to generate a discharge voltage variation equation. The discharge voltage of the equipment end hardware in the converter station valve hall is obtained. The equipment end hardware discharge voltage is substituted into the discharge voltage variation equation to calculate the corresponding air clearance distance of the shielding ball hardware.

[0083] In an embodiment of the present invention, structural data of a shielding ball hardware is obtained and used to calculate the voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, generating boundary voltages corresponding to the preset altitudes. Positive polarity operating impulse discharge tests are then conducted based on the boundary voltages to generate discharge voltage test values ​​corresponding to the preset altitudes. The discharge voltage test values ​​are used to construct a model and perform discharge voltage calculations, generating a discharge voltage calculation model for an intermediate shielding ball hardware and a discharge voltage calculation value corresponding to the preset altitudes. The discharge voltage calculation model for the intermediate shielding ball hardware is updated based on the error between the calculated discharge voltage value and the corresponding discharge voltage test value to generate a target shielding ball hardware discharge voltage calculation model. The target shielding ball hardware discharge voltage calculation model is used to obtain the air clearance corresponding to the shielding ball hardware at the target altitude, generating the corresponding air clearance. This method addresses the technical problem that existing shielding ball hardware air clearance calculation methods, which are typically based on empirical formulas, simplified models, or theoretical assumptions and fail to fully consider the complexity and diversity of real-world engineering environments, resulting in low calculation accuracy. Operating impulse discharge tests based on multiple altitudes provide more accurate calculation of the air clearance of shielding ball hardware.

[0084] Please refer to FIG. 2 , which is a flow chart showing the steps of a method for calculating the air clearance of shielding ball fittings provided in a second embodiment of the present invention.

[0085] Another method for calculating the air clearance of shielding ball hardware provided in Example 2 of the present invention includes:

[0086] Step 201: Obtain structural data of the shielding ball hardware, use the structural data to calculate the voltages corresponding to the overlapped boundaries of the shielding ball hardware at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes.

[0087] Furthermore, step 201 may include the following sub-steps S11-S14:

[0088] S11. Use multi-physics field simulation software to construct a model according to the structural data to generate a ball-plate model corresponding to the shielding ball hardware.

[0089] S12. Performing spherical electrode voltage simulations at multiple preset altitudes on the spherical-plate model according to preset voltage application requirements, and generating electrode change data corresponding to the preset altitudes.

[0090] S13. Substituting the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula respectively to perform boundary calculations, and generating upper boundary data and lower boundary data corresponding to the electrode change data.

[0091] S14. When the upper boundary data is equal to the lower boundary data, the voltage value corresponding to the ball-plate model at the current moment is used as the boundary voltage corresponding to the preset altitude.

[0092] The preset voltage application requirement refers to applying a voltage to the spherical electrode, gradually increasing from 0 kV with a step size of 1 kV. Each increase requires recalculating the upper and lower boundaries of the critical volume.

[0093] In the embodiment of the present invention, the boundary voltage when the upper and lower boundaries of the critical volume of the shielding ball metal fitting coincide at each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m) is calculated. A ball-plate model is established based on Comsol simulation software, i.e., multi-physics field simulation software. A voltage is applied to the ball electrode, gradually increasing from 0kV with a step size of 1kV. Each increase requires recalculating the upper and lower boundaries of the critical volume. When the upper and lower boundaries coincide, the voltage at this time is the desired boundary voltage. The preset upper boundary condition formula is:

[0094] Where d1 represents the electrode surface; d2 represents the distance between the upper boundary and the electrode surface; N crit represents the critical charge number required to form a streamer, which is 0.55×10 -8 ; α is the ionization coefficient; η is the adsorption coefficient; e represents the natural constant, which is 2.718.

[0095] The preset lower boundary condition formula is: α=η;

[0096] Where α is the ionization coefficient; η is the adsorption coefficient; the values ​​of α and η are related to the spatial electric field strength and the relative density of air. The calculation formula for the spatial electric field strength is:

[0097] Where α is the ionization coefficient; η is the adsorption coefficient; E is the electric field strength in space, kV / cm; e represents the natural constant, which is 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0098] Where δ is the relative density of air; t represents the ambient temperature at each altitude, in °C; p represents the atmospheric pressure at each altitude; and p0 represents the standard atmospheric pressure, which is 101 kPa.

[0099] Step 202: Perform a positive polarity operation impulse discharge test according to the boundary voltage to generate a discharge voltage test value corresponding to a preset altitude.

[0100] Furthermore, step 202 may include the following sub-steps S21-S22:

[0101] S21. Simulate the test device according to the structural data to generate the test device.

[0102] S22. According to the boundary voltage corresponding to the preset altitude, a positive polarity operating impulse voltage waveform is used to perform an impulse test on the test device at multiple preset gap distances to generate a discharge voltage test value corresponding to the preset altitude.

[0103] In this embodiment of the present invention, a test device is simulated based on the structural data to generate a test device. The test device consists of an impulse voltage generator 1, a corrugated tube 2, an insulator 3, a crane 4, a three-hole equalizing ball 5, a test specimen 6, and a grounding stake 7. Specifically, the test arrangement is shown in Figure 3, and a corresponding simulation is performed using computing equipment to construct the test device. Busbar connectors and insulator 3 connectors are installed inside the corner ball, and the top is vertically suspended by a composite suspension insulator 3. One end of the high-voltage lead is connected to the corner ball and the other end to the impulse voltage generator 1. Another busbar is arranged vertically, with its upper end connected to the bottom of the corner ball and its other end connected to the test specimen 6. Galvanized iron sheets are laid flat on the hall floor to simulate the ground. During the test, the impulse generator generates a 250 / 2500μs positive polarity operating impulse voltage waveform for the impulse test. When conducting positive polarity operating impulse tests for different gap types, the gap distance can be controlled by the crane 4. Positive polarity operating impulse discharge tests were conducted at various preset altitudes (0m, 1000m, 2000m, 3000m, 4000m, and 5000m) across the ball-plate gap with different preset gap distances (1.00m, 3.00m, 5.00m, 7.00m, and 9.00m). During each altitude test, the voltage was directly increased to the voltage obtained in step 1 and then continued to increase until the gap broke down. This yielded the 50% operating impulse discharge voltage test value, or discharge voltage test value. This method was used to obtain the discharge voltage test value corresponding to each preset altitude.

[0104] Step 203 : constructing a model and performing discharge voltage calculation using the discharge voltage test value to generate a discharge voltage calculation model for the intermediate shielding ball fitting and a discharge voltage calculation value corresponding to a preset altitude.

[0105] Furthermore, step 203 may include the following sub-steps S31-S34:

[0106] S31. Divide the discharge voltage test values ​​corresponding to all preset altitudes according to the same gap spacing to generate multiple model training sets.

[0107] S32. Use the model training set to input the initial shielding ball hardware discharge voltage calculation model to perform parameter calculation and determine the model parameters.

[0108] S33. Using the model parameters, the initial shielding ball hardware discharge voltage calculation model is updated to generate an intermediate shielding ball hardware discharge voltage calculation model.

[0109] S34: Substitute the preset altitude into the discharge voltage calculation model of the intermediate shielding ball hardware for calculation, and generate a discharge voltage calculation value corresponding to the preset altitude.

[0110] In the embodiment of the present invention, a calculation model for the discharge voltage of the initial shielding ball hardware at different altitudes under the same gap distance is established:

[0111] Where U 50 It represents the discharge voltage test value; U0 represents the rod-plate positive polarity operating impulse discharge voltage at an altitude of 0m, and its unit is kV; H represents the altitude, and its unit is m; e represents the natural constant, and its value is 2.718; k represents the shape factor, and its value is determined by the size of the shielding ball and the gap structure. For example, for a shielding ball with a diameter of 1.1m and a gap of 1.5m, the k value is 1.78; for a shielding ball with a diameter of 1.1m and a gap of 3m, the k value is 1.56; A and B represent altitude factors, and k, A, and B are dimensionless.

[0112] The comparison table of 50% switching impulse discharge voltage of rod-plate air gap at different gap distances at 0m altitude is shown in Table 1.

[0113] Table 1 Discharge voltage comparison table

[0114] The 50% operating impulse discharge voltage test value U50 of shielding ball hardware at different preset altitudes is substituted into the model to determine the model parameters. Specifically, the discharge voltage test values ​​corresponding to all preset altitudes are divided according to the same gap spacing to generate multiple model training sets. The model training sets are then input into the initial shielding ball hardware discharge voltage calculation model for parameter calculation to determine the model parameters. The initial shielding ball hardware discharge voltage calculation model is then updated using the model parameters to generate an intermediate shielding ball hardware discharge voltage calculation model. Finally, each preset altitude value is substituted into the intermediate shielding ball hardware discharge voltage calculation model to obtain the calculated 50% operating impulse discharge voltage value (i.e., discharge voltage calculated value) of the shielding ball hardware at each preset altitude.

[0115] Step 204 : updating the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and generating a target shielding ball hardware discharge voltage calculation model.

[0116] Furthermore, step 204 may include the following sub-steps S41-S42:

[0117] S41. Calculate the errors between the calculated discharge voltage value and the corresponding test discharge voltage value using a preset error calculation formula to generate a mean absolute error percentage.

[0118] The preset error calculation formula is:

[0119] Where Y represents the mean absolute error percentage; n represents the number of test altitude points; i is 1, 2, ..., n; U i Indicates the discharge voltage test value at the i-th altitude point; U' i Represents the calculated value of the discharge voltage at the i-th altitude point.

[0120] S42. Update the intermediate shielding ball hardware discharge voltage calculation model according to the mean absolute error percentage and the preset threshold value to generate a target shielding ball hardware discharge voltage calculation model.

[0121] Furthermore, step S42 may include the following sub-steps S421-S424:

[0122] S421. Determine whether the mean absolute error percentage is greater than a preset threshold. If so, execute step S422; if not, execute step S424.

[0123] S422 , calculating the average value between the discharge voltage calculation value and the discharge voltage test value corresponding to the mean absolute error percentage, and generating an adjustment parameter.

[0124] S423: Modify the model parameters of the intermediate shielding ball hardware discharge voltage calculation model using adjustment parameters to generate the target shielding ball hardware discharge voltage calculation model.

[0125] S424: Using the intermediate shielding ball hardware discharge voltage calculation model as the target shielding ball hardware discharge voltage calculation model.

[0126] The preset threshold is a critical value corresponding to the error that is set in advance based on actual needs.

[0127] In an embodiment of the present invention, the error between the calculated value and the test value of the 50% operating impulse discharge voltage is calculated. The error is expressed as a mean absolute error percentage. This means that a preset error calculation formula is used to calculate the error between the calculated discharge voltage value and the corresponding test discharge voltage value, generating a mean absolute error percentage. The error between the calculated value and the test value of the 50% operating impulse discharge voltage is used to determine the validity of the calculation model and perform corrections. Specifically, a determination is made as to whether the mean absolute error percentage is greater than a preset threshold. Specifically, if the mean absolute error percentage is within 10%, the model parameters are deemed valid, and the intermediate shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model. If the mean absolute error percentage is greater than 10%, the average of the calculated value and the test value of the 50% operating impulse discharge voltage at each preset gap distance is used as the 50% operating impulse discharge voltage at that preset gap distance, and the model parameters are corrected. Specifically, the intermediate shielding ball hardware discharge voltage calculation model is corrected using adjustment parameters to generate the target shielding ball hardware discharge voltage calculation model.

[0128] Step 205 : Obtain the discharge voltages of the shielding ball hardware at different gap distances at the target altitude corresponding to the shielding ball hardware through the target shielding ball hardware discharge voltage calculation model, and generate multiple shielding ball hardware discharge voltages.

[0129] In the embodiment of the present invention, based on the target shielding ball hardware discharge voltage calculation model, the 50% operating impulse discharge voltage of the shielding ball hardware with different gap distances at the target altitude H1 can be obtained, thereby obtaining multiple shielding ball hardware discharge voltages.

[0130] Step 206: Perform nonlinear function fitting using the discharge voltage of the shielding ball hardware to generate a discharge voltage variation relationship.

[0131] In the embodiment of the present invention, the discharge voltage of the shielding ball hardware with different gap distances at the target altitude H1 is fitted by a nonlinear function to obtain a characteristic curve of the shielding ball hardware discharge voltage as a function of gap distance and a relationship between the 50% operating impulse discharge voltage of the shielding ball hardware and the gap distance, i.e., the discharge voltage variation relationship, which is: U 50％ =ad 2 +bd+c;

[0132] Where U 50％ It represents the 50% operating impulse discharge voltage of shielding ball hardware, and its unit is kV; d is the gap distance, and its unit is m; a, b and c are parameters.

[0133] Step 207: Obtain the discharge voltage of the equipment end fittings in the converter station valve hall.

[0134] In the embodiment of the present invention, the 50% operating impulse discharge voltage of the equipment end fittings in the converter station valve hall is calculated based on the typical impulse insulation withstand voltage level inside the converter station valve hall. The required minimum safe clearance is calculated according to the clearance formula under standard meteorological conditions. The 50% operating impulse discharge voltage used for the minimum air gap calculation is the equipment end fitting discharge voltage U 50 for:

[0135] Where U w It indicates the impulse insulation withstand level (SIWL, LIWL) of the equipment; σ is the coefficient of variation of the air gap impulse discharge voltage, which is generally 6% and 3% for operation and lightning impulse respectively.

[0136] Step 208: Substitute the discharge voltage of the equipment end fitting into the discharge voltage variation equation to calculate the air clearance corresponding to the shielding ball fitting.

[0137] In this embodiment of the present invention, the air clearance distance of the shielding ball hardware at the target altitude can be calculated based on the relationship between the 50% operating impulse discharge voltage of the shielding ball hardware and the gap distance. Specifically, the discharge voltage of the hardware at the equipment end is substituted into the discharge voltage relationship to calculate the corresponding air clearance distance of the shielding ball hardware.

[0138] Specifically, as shown in Figures 3 and 4, the present invention conducts a switching impulse discharge test on a 1.1m diameter metal shielding sphere and predicts its air clearance at an altitude of 3800m. The test voltage waveform uses a 250 / 2500μs standard switching impulse.

[0139] Step 1: Calculate the boundary voltage when the upper and lower boundaries of the critical volume of the shielding spherical metal fitting coincide at each altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m). When the upper and lower boundaries coincide, the voltage at that point is the boundary voltage U. c , calculate U at each altitude separately c1 , U c2 , U c3 , U c4 , U c5 , U c6 .

[0140] Step 2. Arrange the test as shown in Figure 3, place a 1.1m diameter shielding ball vertically on the ground, and perform positive polarity operating impulse discharge tests on the ball-plate gaps with different gap distances (1.00m, 3.00m, 5.00m, 7.00m, 9.00m) at various altitudes (0m, 1000m, 2000m, 3000m, 4000m, 5000m). During the test at each altitude, directly increase the voltage to the boundary voltage obtained in step 1, and then continue to increase the pressure until the gap breaks down, obtaining a 50% operating impulse discharge voltage test value, i.e., a discharge voltage test value.

[0141] Step 3: Establish a calculation model for the discharge voltage of shielding ball hardware at different altitudes under the same gap distance, namely, the initial calculation model for the discharge voltage of shielding ball hardware. Substitute the 50% operating impulse discharge voltage test values ​​of shielding ball hardware at different altitudes into the model to determine the model parameters.

[0142] Step 4: Substitute the preset altitude into the discharge voltage calculation model of the intermediate shielding ball hardware for calculation to generate the discharge voltage calculation value corresponding to the preset altitude; and calculate the error between the 50% operating impulse discharge voltage calculation value and the test value. The error is the mean absolute error percentage, that is, the error between the discharge voltage calculation value and the corresponding discharge voltage test value is calculated to generate the mean absolute error percentage.

[0143] Step 5: Determine the validity of the calculation model based on the error between the calculated and tested 50% operating impulse discharge voltage values ​​and make corrections. If the error is within 10%, the model parameters are considered valid. If the error is greater than 10%, the average of the calculated and tested 50% operating impulse discharge voltage values ​​at each gap distance is used as the 50% operating impulse discharge voltage at that gap distance. The model parameters are then corrected to determine the new discharge voltage calculation model, which is the target shielding ball hardware discharge voltage calculation model.

[0144] Step 6. Based on the discharge voltage calculation model, the 50% operating impulse discharge voltage of the shielding ball hardware at different gap distances at the target altitude can be obtained, and the characteristic curve of the shielding ball hardware discharge voltage changing with the gap distance can be obtained through nonlinear function fitting, and the relationship between the 50% operating impulse discharge voltage of the shielding ball hardware and the gap distance, that is, the discharge voltage change relationship, can be obtained.

[0145] Step 7: Based on the typical impulse insulation withstand voltage level within the converter station valve hall, calculate the 50% operating impulse discharge voltage of the converter station valve hall equipment end fittings, that is, the discharge voltage of the equipment end fittings in the converter station valve hall. For the 800kV converter station DC main equipment operating impulse withstand voltage of 1600kV, the corresponding U50 voltage is calculated to be 1818kV. Based on the relationship between the 50% operating impulse discharge voltage of the shielding ball fittings and the gap distance obtained in Step 5, the air clearance of the shielding ball fittings at the target altitude can be obtained. The calculated air clearance of the 1.1m shielding ball fittings in the 800kV converter station valve hall at an altitude of 3800m is 8.054m.

[0146] Specifically, as shown in Figures 3 and 5, the embodiments of the present invention will conduct an operating impulse discharge test on a 1.1m diameter metal shielding ball and predict its air clearance at an altitude of 4500m. The test voltage waveform uses a 250 / 2500μs standard operating impulse. According to the above steps 1 to 7, it can be calculated that the air clearance of the 1.1m shielding ball metal fitting in the valve hall of an 800kV converter station at an altitude of 4500m is 8.685m. According to the calculations in various embodiments, k = 1.47 ~ 1.78, A = 350.9 ~ 474.7, and B = 0.2 ~ 1.5.

[0147] In an embodiment of the present invention, a target shielding ball hardware discharge voltage calculation model is established based on operating impulse discharge tests at multiple altitudes and gap distances, making the calculation of the shielding ball hardware air clearance more accurate. This target shielding ball hardware discharge voltage calculation model takes into account factors such as electrode shape and altitude, and incorporates a relatively complete database of operating impulse discharge voltages for rod-plate gaps at 0 m altitude, making the model more practical. A characteristic curve and relationship between the shielding ball hardware discharge voltage and gap distance are obtained through nonlinear function fitting. The shielding ball hardware air clearance at the target altitude is calculated based on the typical impulse insulation withstand voltage levels within the converter station valve hall. This model provides a reference for ensuring the safety and cost-effective design and installation of converter station valve hall hardware in actual projects. It not only accurately determines the shielding ball hardware air clearance, improving design quality, but also reduces workload and saves significant costs. It can be widely applied to the selection of air clearances for shielding ball hardware in converter station valve halls.

[0148] Please refer to FIG. 6 , which is a structural block diagram of a shielding ball fitting air clearance calculation system provided in a third embodiment of the present invention.

[0149] A shielding ball fitting air clearance calculation system provided in Example 3 of the present invention includes:

[0150] The boundary voltage generating module 601 is used to obtain the structural data of the shielding ball hardware, calculate the voltage corresponding to the boundary overlap of the shielding ball hardware at multiple preset altitudes using the structural data, and generate the boundary voltage corresponding to the preset altitude.

[0151] The discharge voltage test value generating module 602 is configured to perform a positive polarity operation impulse discharge test according to a boundary voltage, and generate a discharge voltage test value corresponding to a preset altitude.

[0152] The discharge voltage calculation value generating module 603 is used to construct a model and perform discharge voltage calculation using the discharge voltage test value, and generate a discharge voltage calculation model of the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to a preset altitude.

[0153] The calculation model generation module 604 is used to update the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and generate a target shielding ball hardware discharge voltage calculation model.

[0154] The air clearance generation module 605 is used to obtain the air clearance at the target altitude corresponding to the shielding ball hardware through the target shielding ball hardware discharge voltage calculation model, and generate the air clearance corresponding to the shielding ball hardware.

[0155] Optionally, the boundary voltage generating module 601 includes:

[0156] The ball-plate model generation module is used to construct a model according to the structural data using multi-physics field simulation software to generate a ball-plate model corresponding to the shielding ball hardware.

[0157] The electrode change data generation module is used to perform ball electrode voltage simulation at multiple preset altitudes on the ball-plate model according to the preset voltage application requirements, and generate electrode change data corresponding to the preset altitudes.

[0158] The upper boundary data and lower boundary data generation module is used to substitute the electrode change data into the preset upper boundary condition formula and the preset lower boundary condition formula for boundary calculation, and generate the upper boundary data and lower boundary data corresponding to the electrode change data.

[0159] The preset upper boundary condition formula is:

[0160] Where d1 represents the electrode surface; d2 represents the distance between the upper boundary and the electrode surface; N crit represents the critical charge number required to form a streamer, which is 0.55×10 -8 ; α is the ionization coefficient; η is the adsorption coefficient; e represents the natural constant, which is 2.718.

[0161] The preset lower boundary condition formula is: α=η;

[0162] Where α is the ionization coefficient; η is the adsorption coefficient; the values ​​of α and η are related to the spatial electric field strength and the relative density of air. The calculation formula for the spatial electric field strength is:

[0163] Where α is the ionization coefficient; η is the adsorption coefficient; E is the electric field strength in space, kV / cm; e represents the natural constant, which is 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0164] Where δ is the relative density of air; t represents the ambient temperature at each altitude, in °C; p represents the atmospheric pressure at each altitude; and p0 represents the standard atmospheric pressure, which is 101 kPa.

[0165] The boundary voltage generation submodule is used to use the voltage value corresponding to the ball-plate model at the current moment as the boundary voltage corresponding to the preset altitude when the upper boundary data is equal to the lower boundary data.

[0166] Optionally, the discharge voltage test value generating module 602 includes:

[0167] The test device generation module is used to simulate the test device according to the structural data and generate the test device.

[0168] The discharge voltage test value generation submodule is used to perform multiple impact tests of preset gap distances on the test device using a positive polarity operating impact voltage waveform according to the boundary voltage corresponding to the preset altitude, and generate the discharge voltage test value corresponding to the preset altitude.

[0169] Optionally, the discharge voltage calculation value generating module 603 includes:

[0170] The model training set generation module is used to divide the discharge voltage test values ​​corresponding to all preset altitudes according to the same gap spacing to generate multiple model training sets.

[0171] The model parameter determination module is used to use the model training set to input the initial shielding ball hardware discharge voltage calculation model to perform parameter calculation and determine the model parameters.

[0172] The calculation model of the initial shielding ball hardware discharge voltage is:

[0173] Where U 50Indicates the discharge voltage test value; U0 represents the rod-plate positive polarity operating impulse discharge voltage at an altitude of 0m, in kV; H represents the altitude, in meters; e represents a natural constant, which is 2.718; k represents a shape factor, whose value is determined by the size of the shielding ball and the gap structure; A and B represent altitude factors, and k, A, and B are dimensionless.

[0174] The intermediate shielding ball hardware discharge voltage calculation model generation module is used to update the initial shielding ball hardware discharge voltage calculation model using model parameters to generate the intermediate shielding ball hardware discharge voltage calculation model.

[0175] The discharge voltage calculation value generation module is used to substitute the preset altitude into the intermediate shielding ball hardware discharge voltage calculation model for calculation, and generate the discharge voltage calculation value corresponding to the preset altitude.

[0176] Optionally, the calculation model generation module 604 includes:

[0177] The mean absolute error percentage generating module is used to calculate the error between the discharge voltage calculated value and the corresponding discharge voltage test value using a preset error calculation formula to generate a mean absolute error percentage.

[0178] The preset error calculation formula is:

[0179] Where Y represents the mean absolute error percentage; n represents the number of test altitude points; i is 1, 2, ..., n; U i Indicates the discharge voltage test value at the i-th altitude point; U' i Represents the calculated value of the discharge voltage at the i-th altitude point.

[0180] The target shielding ball hardware discharge voltage calculation model generation submodule is used to update the intermediate shielding ball hardware discharge voltage calculation model according to the mean absolute error percentage and the preset threshold value to generate the target shielding ball hardware discharge voltage calculation model.

[0181] Optionally, the target shielding ball hardware discharge voltage calculation model generation submodule may perform the following steps:

[0182] Determine whether the mean absolute error percentage is greater than a preset threshold;

[0183] If so, the average value between the calculated discharge voltage value and the test discharge voltage value corresponding to the mean absolute error percentage is calculated to generate the adjustment parameter;

[0184] The model parameters of the intermediate shielding ball hardware discharge voltage calculation model are modified by using adjustment parameters to generate the target shielding ball hardware discharge voltage calculation model;

[0185] If not, the discharge voltage calculation model of the intermediate shielding ball hardware is used as the discharge voltage calculation model of the target shielding ball hardware.

[0186] Optionally, the air clearance generation module 605 includes:

[0187] The shielding ball hardware discharge voltage generation module is used to obtain the discharge voltage of the shielding ball hardware at different gap distances under the target altitude corresponding to the target shielding ball hardware through the target shielding ball hardware discharge voltage calculation model, and generate multiple shielding ball hardware discharge voltages.

[0188] The discharge voltage variation relationship generation module is used to perform nonlinear function fitting using the shielded ball hardware discharge voltage to generate a discharge voltage variation relationship.

[0189] The equipment end fitting discharge voltage acquisition module is used to obtain the equipment end fitting discharge voltage of the converter station valve hall.

[0190] The air clearance generation submodule is used to substitute the discharge voltage of the equipment end fittings into the discharge voltage change relationship to calculate the air clearance corresponding to the shielding ball fittings.

[0191] An embodiment of the present invention further provides an electronic device, comprising: a memory and a processor, wherein a computer program is stored in the memory; when the computer program is executed by the processor, the processor executes the air clearance calculation method for shielding ball hardware as described in any of the above embodiments.

[0192] The memory can be an electronic memory such as a flash memory, an EEPROM (Electrically Erasable Programmable Read-Only Memory), an EPROM, a hard disk, or a ROM. The memory has storage space for program codes for executing any of the method steps in the above method. For example, the storage space for program codes can include individual program codes for implementing the various steps in the above method. These program codes can be read from or written to one or more computer program products. These computer program products include program code carriers such as a hard disk, a compact disk (CD), a memory card, or a floppy disk. The program code can be compressed, for example, in an appropriate form. When these codes are run by a computing and processing device, the computing and processing device executes the various steps in the shielded ball hardware air clearance calculation method described above.

[0193] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for calculating the air clearance of shielding ball hardware according to any of the above embodiments is implemented.

[0194] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0195] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0196] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0197] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0198] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, and other media that can store program code.

[0199] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for calculating the air clearance of a shielding ball fitting, characterized in that, it includes: Obtain the structural data of the shielding ball fitting, and use the structural data to calculate the voltages corresponding to the boundary coincidence of the shielding ball fitting at multiple preset altitudes respectively, and generate the boundary voltages corresponding to the preset altitudes; Conduct positive polarity operating impulse discharge tests respectively according to the boundary voltages, and generate the test values of the discharge voltages corresponding to the preset altitudes; Use the test values of the discharge voltages to construct a model and calculate the discharge voltages, and generate an intermediate shielding ball fitting discharge voltage calculation model and the calculated values of the discharge voltages corresponding to the preset altitudes; Update the intermediate shielding ball fitting discharge voltage calculation model according to the error between the calculated value of the discharge voltage and the corresponding test value of the discharge voltage, and generate a target shielding ball fitting discharge voltage calculation model; Obtain the air clearance corresponding to the target altitude of the shielding ball fitting through the target shielding ball fitting discharge voltage calculation model, and generate the air clearance corresponding to the shielding ball fitting.

2. The method for calculating the air clearance of a shielding ball fitting according to claim 1, characterized in that, The step of using the structural data to calculate the voltages corresponding to the boundary coincidence of the shielding ball fitting at multiple preset altitudes respectively, and generating the boundary voltages corresponding to the preset altitudes includes: Use multi-physics field simulation software to construct a model according to the structural data, and generate a sphere-plate model corresponding to the shielding ball fitting; Conduct sphere electrode voltage simulations at multiple preset altitudes on the sphere-plate model according to the preset voltage application requirements, and generate the electrode change data corresponding to the preset altitudes; Substitute the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula respectively for boundary calculation, and generate the upper boundary data and the lower boundary data corresponding to the electrode change data; The preset upper boundary condition formula is as follows: where d 1 represents the electrode surface; d 2 represents the distance from the upper boundary to the electrode surface; N crit represents The critical charge number required to form a streamer, with a value of 0.55×10 -8 ; α is the ionization coefficient; η is the adsorption coefficient; e represents the natural constant, taking the value of 2.718; The preset lower boundary condition formula is: α = η; In the formula, α is the ionization coefficient; η is the adsorption coefficient; the values of α and η are related to the spatial electric field strength and the relative air density. The calculation formula for the spatial electric field strength is: Wherein, α is the ionization coefficient; η is the adsorption coefficient; E is the spatial electric field strength, kV / cm; e represents the natural constant, taking 2.718; δ is the relative air density, and the calculation formula for the relative air density is: Where δ is the relative air density; t represents the ambient temperature at each altitude in °C; p represents the atmospheric pressure at each altitude; p 0 represents the standard atmospheric pressure, with a value of 101 kPa; When the upper boundary data is equal to the lower boundary data, use the voltage value corresponding to the sphere-plate model at the current moment as the boundary voltage corresponding to the preset altitude.

3. The method for calculating the air clearance of a shielding ball fitting according to claim 1, characterized in that, The step of conducting positive polarity operating impulse discharge tests respectively according to the boundary voltages, and generating the test values of the discharge voltages corresponding to the preset altitudes includes: Conduct simulation of the test device according to the structural data, and generate a test device; According to the boundary voltage corresponding to the preset altitude, use a positive polarity operating impulse voltage waveform to conduct impulse tests on the test device at multiple preset gap distances, and generate the test values of the discharge voltages corresponding to the preset altitudes.

4. The method for calculating the air clearance of a shielding ball fitting according to claim 1, characterized in that, The step of using the test values of the discharge voltages to construct a model and calculate the discharge voltages, and generating an intermediate shielding ball fitting discharge voltage calculation model and the calculated values of the discharge voltages corresponding to the preset altitudes includes: Divide the discharge voltage test values corresponding to all the preset altitude heights according to the same gap spacing to generate multiple model training sets; Use the model training sets to input the initial discharge voltage calculation model of the shielding ball fitting respectively for parameter calculation to determine the model parameters; The discharge voltage calculation model of the initial shielding ball fitting is as follows: Wherein, U 50 represents the test value of the discharge voltage; U 0 represents the rod - plate positive - polarity switching impulse discharge voltage at an altitude of 0 m, and its unit is kV; H represents the altitude, and its unit is m; e represents the natural constant, taking 2.718; k represents the shape factor, and its value is determined by the size of the shielding ball and the gap structure; A and B represent the altitude factors, and k, A, and B are dimensionless; Update the initial discharge voltage calculation model of the shielding ball fitting with the model parameters to generate an intermediate discharge voltage calculation model of the shielding ball fitting; Substitute the preset altitude height into the intermediate discharge voltage calculation model of the shielding ball fitting for calculation to generate the calculated discharge voltage value corresponding to the preset altitude height.

5. The method for calculating the air clearance of the shielding ball fitting according to claim 1, characterized in that, the step of updating the intermediate discharge voltage calculation model of the shielding ball fitting according to the error between the calculated discharge voltage value and the corresponding discharge voltage test value to generate a target discharge voltage calculation model of the shielding ball fitting includes; Use a preset error calculation formula to calculate the error between the calculated discharge voltage value and the corresponding discharge voltage test value respectively to generate a mean absolute error percentage; The formula for the preset error is as follows: Wherein, Y represents the percentage of mean absolute error; n represents the number of test altitude points; i takes values of 1, 2, …, n; U i represents the test value of the discharge voltage at the i-th altitude point; U i ' represents the calculated value of the discharge voltage at the i-th altitude point; Update the intermediate discharge voltage calculation model of the shielding ball fitting according to the mean absolute error percentage and a preset threshold to generate a target discharge voltage calculation model of the shielding ball fitting.

6. The method for calculating the air clearance of the shielding ball fitting according to claim 5, characterized in that, the step of updating the intermediate discharge voltage calculation model of the shielding ball fitting according to the mean absolute error percentage and a preset threshold to generate a target discharge voltage calculation model of the shielding ball fitting includes: Judge whether the mean absolute error percentage is greater than a preset threshold; If so, calculate the average value between the calculated discharge voltage value corresponding to the mean absolute error percentage and the discharge voltage test value to generate an adjustment parameter; Use the adjustment parameter to correct the model parameters of the intermediate discharge voltage calculation model of the shielding ball fitting to generate a target discharge voltage calculation model of the shielding ball fitting; If not, use the intermediate discharge voltage calculation model of the shielding ball fitting as the target discharge voltage calculation model of the shielding ball fitting.

7. The method for calculating the air clearance of the shielding ball fitting according to claim 1, characterized in that, the step of obtaining the air clearance corresponding to the shielding ball fitting at the target altitude corresponding to the shielding ball fitting through the target discharge voltage calculation model of the shielding ball fitting to generate the air clearance corresponding to the shielding ball fitting includes: Obtain the discharge voltages at different gap distances at the target altitude corresponding to the shielding ball fitting through the target discharge voltage calculation model of the shielding ball fitting to generate multiple discharge voltages of the shielding ball fitting; Use the discharge voltages of the shielding ball fitting for non-linear function fitting to generate a discharge voltage change relation; Obtain the discharge voltage of the equipment end fitting in the converter valve hall; Substitute the discharge voltage of the equipment end fitting into the discharge voltage change relation to calculate and obtain the air clearance corresponding to the shielding ball fitting.

8. A system for calculating the air clearance of a shielding ball fitting, characterized in that, comprising: A boundary voltage generation module, configured to obtain the structural data of the shielding ball fitting, calculate the voltages corresponding to the boundary coincidence of the shielding ball fitting at multiple preset altitudes by using the structural data, and generate the boundary voltages corresponding to the preset altitudes; A discharge voltage test value generation module, configured to perform a positive polarity switching impulse discharge test respectively according to the boundary voltages, and generate the discharge voltage test values corresponding to the preset altitudes; A discharge voltage calculation value generation module, configured to perform model construction by using the discharge voltage test values and perform discharge voltage calculation, and generate an intermediate shielding ball fitting discharge voltage calculation model and the discharge voltage calculation values corresponding to the preset altitudes; A calculation model generation module, configured to update the intermediate shielding ball fitting discharge voltage calculation model according to the error between the discharge voltage calculation values and the corresponding discharge voltage test values, and generate a target shielding ball fitting discharge voltage calculation model; An air clearance generation module, configured to obtain the air clearance corresponding to the target altitude of the shielding ball fitting through the target shielding ball fitting discharge voltage calculation model, and generate the air clearance corresponding to the shielding ball fitting.

9. An electronic device characterized in that it includes a memory and a processor, and a computer program is stored in the memory. When the computer program is executed by the processor, the processor is caused to execute the steps of the method for calculating the air clearance of the shielding ball fitting according to any one of claims 1 to 7.

10. A computer-readable storage medium, on which a computer program is stored characterized in that when the computer program is executed, the method for calculating the air clearance of the shielding ball fitting according to any one of claims 1 to 7 is implemented. ​

Images