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

Abstract

The present invention discloses a method, system, device and medium for calculating the air clearance of shielded ball hardware, and relates to the field of hardware technology. The voltages corresponding to the boundary overlap of the shielded ball hardware at multiple preset altitudes are calculated respectively, and the corresponding boundary voltages are generated. Positive polarity operation impact discharge tests are performed respectively according to the boundary voltages to generate discharge voltage test values. The discharge voltage test values ​​are used to construct a model and perform discharge voltage calculations to generate an intermediate shielded ball hardware discharge voltage calculation model and a discharge voltage calculation value. The intermediate shielded ball hardware discharge voltage calculation model is updated according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value to generate a target shielded ball hardware discharge voltage calculation model. The air clearance at the target altitude corresponding to the shielded ball hardware is obtained through the target shielded ball hardware discharge voltage calculation model. Based on the operation impact discharge test at multiple altitudes, the air clearance calculation result is more accurate.

Description

Technical Field

[0001] The 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

[0002] The converter valve is a key device for DC power transmission and conversion. Inside the converter valve, shielding ball fittings are widely used to reduce electromagnetic interference and improve system stability. The shielding ball fittings form a shielding effect by reasonably arranging the gap between the shielding ball fittings and the surrounding environment, reducing the interference of electric and magnetic fields and ensuring the safe and reliable operation of the converter valve. However, in order to ensure the effectiveness of the shielding ball fittings, it is crucial to ensure the air clearance between it and the surrounding environment.

[0003] Air clearance refers to the minimum vertical gap between the shielding ball fittings and the surrounding metal surface (such as chopping board, partition, etc.). Accurate calculation of air clearance can help avoid arc discharge, breakdown and other faults, protect the converter valve equipment and improve system performance.

[0004] At present, there are some problems and limitations in the calculation method of the air clearance of shielding ball fittings in converter valves. The existing calculation method of the air clearance of shielding ball fittings is usually based on empirical formulas, simplified models or theoretical assumptions, which cannot fully consider the complexity and diversity of the real engineering environment, resulting in low accuracy of the calculation results. Summary of the invention

[0005] 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 method for calculating the air clearance of shielded ball hardware is 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.

[0006] The present invention provides a method for calculating the air clearance of shielding ball hardware, comprising:

[0007] Acquire structural data of the shielding ball fitting, and use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fitting at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes;

[0008] Performing positive polarity operation impulse discharge tests according to the boundary voltages respectively to generate discharge voltage test values ​​corresponding to the preset altitudes;

[0009] The discharge voltage test value is used to construct a model and perform discharge voltage calculation, to generate a discharge voltage calculation model for an intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude;

[0010] The intermediate shielding ball hardware discharge voltage calculation model is updated 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;

[0011] 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.

[0012] Optionally, the step of using the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fittings at multiple preset altitudes to generate the boundary voltages corresponding to the preset altitudes includes:

[0013] Using multi-physics field simulation software to construct a model according to the structural data, and generating a ball-plate model corresponding to the shielding ball fitting;

[0014] According to the preset voltage application requirements, the ball electrode voltage simulations at multiple preset altitudes are respectively performed on the ball-plate model to generate electrode change data corresponding to the preset altitudes;

[0015] Substituting the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula to perform boundary calculations, thereby generating upper boundary data and lower boundary data corresponding to the electrode change data;

[0016] The preset upper boundary condition formula is:

[0017]

[0018] 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;

[0019] The preset lower boundary condition formula is:

[0020] α = η;

[0021] 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 density of air. The calculation formula for the spatial electric field strength is:

[0022]

[0023]

[0024] In the formula, α is the ionization coefficient; η is the adsorption coefficient; E is the spatial electric field intensity, kV / cm; e represents the natural constant, which is taken as 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0025]

[0026] In the formula, 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;

[0027] 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.

[0028] 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:

[0029] Simulating the test device according to the structural data to generate the test device;

[0030] 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.

[0031] 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 an intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude includes:

[0032] Dividing the discharge voltage test values ​​corresponding to all the preset altitudes according to the same gap spacing to generate multiple model training sets;

[0033] 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;

[0034] The calculation model of the discharge voltage of the initial shielding ball hardware is:

[0035]

[0036] 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, which is 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;

[0037] The model parameters are used to update the initial shielding ball hardware discharge voltage calculation model to generate an intermediate shielding ball hardware discharge voltage calculation model;

[0038] The preset altitude is substituted into the intermediate shielding ball hardware discharge voltage calculation model for calculation to generate a discharge voltage calculation value corresponding to the preset altitude.

[0039] 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:

[0040] The errors between the discharge voltage calculation value and the corresponding discharge voltage test value are calculated using a preset error calculation formula to generate a mean absolute error percentage;

[0041] The preset error calculation formula is:

[0042]

[0043] 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 ith altitude point; U i ' represents the calculated value of the discharge voltage at the i-th altitude point;

[0044] The intermediate shielding ball hardware discharge voltage calculation model is updated according to the mean absolute error percentage and the preset threshold value to generate a target shielding ball hardware discharge voltage calculation model.

[0045] 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:

[0046] Determine whether the mean absolute error percentage is greater than a preset threshold;

[0047] If yes, then 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 an adjustment parameter;

[0048] The adjustment parameters are used 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;

[0049] If not, the intermediate shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model.

[0050] 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 comprises:

[0051] The discharge voltage of the shielding ball hardware at different gap distances under the target altitude corresponding to the shielding ball hardware is obtained through the target shielding ball hardware discharge voltage calculation model, and a plurality of shielding ball hardware discharge voltages are generated;

[0052] The discharge voltage of the shielding ball hardware is used to perform nonlinear function fitting to generate a discharge voltage variation relationship;

[0053] Obtaining the discharge voltage of the equipment end fittings in the valve hall of the converter station;

[0054] 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.

[0055] The present invention also provides a shielding ball hardware air clearance calculation system, comprising:

[0056] A boundary voltage generating module, used to obtain structural data of the shielding ball fittings, and use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fittings at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes;

[0057] A discharge voltage test value generating module, used 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;

[0058] A discharge voltage calculation value generation module, used to use the discharge voltage test value to build 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;

[0059] A calculation model generation module, used for updating the discharge voltage calculation model of the intermediate shielding ball hardware 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;

[0060] 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.

[0061] The present invention also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, 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.

[0062] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed, any of the above-mentioned methods for calculating the air clearance of shielded ball fittings is implemented.

[0063] It can be seen from the above technical solutions that the present invention has the following advantages:

[0064] The present invention obtains structural data of shielding ball hardware, and uses the structural data to respectively calculate the voltage corresponding to the boundary overlap of the shielding ball hardware at multiple preset altitudes, and generates the boundary voltage corresponding to the preset altitude. Positive polarity operation impulse discharge test is performed according to the boundary voltage respectively, and the discharge voltage test value corresponding to the preset altitude is generated. Model construction is performed and discharge voltage calculation is performed using the discharge voltage test value, and a discharge voltage calculation model of the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to the preset altitude are generated. The discharge voltage calculation model of the intermediate shielding ball hardware is updated based on the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and a target shielding ball hardware discharge voltage calculation model is generated. 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. The existing shielding ball hardware air clearance calculation method is solved, which is usually based on empirical formulas, simplified models or theoretical assumptions, and cannot fully consider the complexity and diversity of the real engineering environment, thereby resulting in low accuracy of the calculation result. Based on the operation impulse discharge test at multiple altitudes, the calculation of the air clearance of the shielding ball hardware is more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative labor.

[0066] Figure 1 A flowchart of a method for calculating the air clearance of a shielding ball fitting provided in the first embodiment of the present invention;

[0067] Figure 2 A flowchart of the steps of a method for calculating the air clearance of shielding ball fittings provided in the second embodiment of the present invention;

[0068] Figure 3 A layout diagram of a positive polarity standard operating impulse discharge test provided in Example 2 of the present invention;

[0069] Figure 4 A characteristic curve diagram of 50% operating impulse discharge voltage U50%-air clearance d of a 1.1m shielded ball fitting at an altitude of 3800m provided in the second embodiment of the present invention;

[0070] Figure 5 A characteristic curve diagram of 50% operating impulse discharge voltage U50%-air clearance d of a 1.1m shielded ball fitting at an altitude of 4500m provided in the second embodiment of the present invention;

[0071] Figure 6 This is a structural block diagram of a shielding ball fitting air clearance calculation system provided in Example 3 of the present invention.

[0072] Figure 3 The reference numerals in the drawings are:

[0073] 1. Impulse voltage generator; 2. Bellows; 3. Insulator; 4. Crane; 5. Three-hole equalizing ball; 6. Test sample; 7. Grounding pile. DETAILED DESCRIPTION

[0074] The 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 the existing method for calculating the air clearance of shielded ball hardware is 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.

[0075] 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 creative work are within the scope of protection of the present invention.

[0076] See also Figure 1 , Figure 1 A flowchart of the steps of a method for calculating the air clearance of a shielding ball fitting provided in Embodiment 1 of the present invention.

[0077] A method for calculating the air clearance of shielding ball fittings provided in Example 1 of the present invention includes:

[0078] Step 101: Acquire structural data of the shielding ball hardware, use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball hardware at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes.

[0079] 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, 5000m.

[0080] In an embodiment of the present invention, the structural data of the shielding ball hardware is obtained, and the 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, 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 substituted into the preset upper boundary condition formula and the preset lower boundary condition formula for boundary calculation, and the upper boundary data and lower boundary data corresponding to the electrode change data are generated. 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.

[0081] 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.

[0082] In the embodiment of the present invention, the test device is simulated according to the structural data to generate the test device, and the test device is subjected to multiple impact tests of preset gap distances using a positive polarity operating impulse voltage waveform according to the boundary voltage corresponding to the preset altitude, and the discharge voltage test value corresponding to the preset altitude is generated. Specifically, at each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m), the ball-plate gaps of different preset gap distances (1.00m, 3.00m, 5.00m, 7.00m, 9.00m) are subjected to positive polarity operating impulse discharge tests respectively, so as to obtain the 50% operating impulse discharge voltage test value corresponding to each preset altitude, i.e., the discharge voltage test value.

[0083] 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 fitting and a discharge voltage calculation value corresponding to a preset altitude.

[0084] In an embodiment of the present invention, a shielding ball hardware discharge voltage calculation model for different preset altitudes under the same gap distance is established, and 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 respectively substituted into the intermediate shielding ball hardware discharge voltage calculation model for calculation to obtain the 50% operating impulse discharge voltage calculation value of the shielding ball hardware at each preset altitude, that is, the discharge voltage calculation value.

[0085] 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 the target shielding ball hardware discharge voltage calculation model.

[0086] In the embodiment of the present invention, the preset error calculation formula is used to calculate the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and the average absolute error percentage is generated. The intermediate shielding ball hardware discharge voltage calculation model is updated based on the average absolute error percentage and the preset threshold value to generate the target shielding ball hardware discharge voltage calculation model.

[0087] 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.

[0088] In an embodiment of the present invention, the discharge voltage of the shielding ball fitting at different gap distances at the target altitude is obtained through the target shielding ball fitting discharge voltage calculation model, and multiple shielding ball fitting discharge voltages are generated. The shielding ball fitting discharge voltage is used for nonlinear function fitting to generate a discharge voltage change relationship. The equipment end fitting discharge voltage of the converter station valve hall is obtained. The equipment end fitting discharge voltage is substituted into the discharge voltage change relationship to calculate the air clearance corresponding to the shielding ball fitting.

[0089] In an embodiment of the present invention, by obtaining the structural data of the shielding ball hardware, the structural data is used to calculate the voltage corresponding to the boundary overlap of the shielding ball hardware at multiple preset altitudes, and the boundary voltage corresponding to the preset altitude is generated. The positive polarity operation impulse discharge test is performed according to the boundary voltage, and the discharge voltage test value corresponding to the preset altitude is generated. The discharge voltage test value is used to construct a model and perform discharge voltage calculation, and a discharge voltage calculation model of the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to the preset altitude are generated. The discharge voltage calculation model of the intermediate shielding ball hardware is updated according to the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and a target shielding ball hardware discharge voltage calculation model is generated. 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. The existing shielding ball hardware air clearance calculation method is usually based on empirical formulas, simplified models or theoretical assumptions, and cannot fully consider the complexity and diversity of the real engineering environment, thereby resulting in low accuracy of the calculation results. Based on the operation impulse discharge test at multiple altitudes, the calculation of the air clearance of the shielding ball hardware is more accurate.

[0090] See also Figure 2 , Figure 2 A flowchart of the steps of a method for calculating the air clearance of a shielding ball fitting provided in Embodiment 2 of the present invention.

[0091] Another method for calculating the air clearance of shielding ball fittings provided in Example 2 of the present invention includes:

[0092] Step 201: Obtain structural data of the shielding ball hardware, use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball hardware at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes.

[0093] Further, step 201 may include the following sub-steps S11-S14:

[0094] 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 fitting.

[0095] S12. According to the preset voltage application requirements, the ball electrode voltage simulations at multiple preset altitudes are respectively performed on the ball-plate model to generate electrode change data corresponding to the preset altitudes.

[0096] S13, substituting the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula to perform boundary calculation, and generating upper boundary data and lower boundary data corresponding to the electrode change data.

[0097] 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.

[0098] 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, and each increase requires recalculating the upper and lower boundaries of the critical volume.

[0099] 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 fittings coincide at each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m) is calculated respectively. Based on Comsol simulation software, i.e., multi-physics field simulation software, a ball-plate model is established, and 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:

[0100]

[0101] 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.

[0102] The default lower boundary condition formula is:

[0103] α = η;

[0104] 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 density of air. The calculation formula for the spatial electric field strength is:

[0105]

[0106]

[0107] In the formula, α is the ionization coefficient; η is the adsorption coefficient; E is the spatial electric field intensity, kV / cm; e represents the natural constant, which is taken as 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0108]

[0109] 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.

[0110] 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.

[0111] Further, step 202 may include the following sub-steps S21-S22:

[0112] S21. Simulate the test device according to the structural data to generate the test device.

[0113] 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 a plurality of preset gap distances to generate a discharge voltage test value corresponding to the preset altitude.

[0114] In the embodiment of the present invention, the test device is simulated according to the structural data to generate the test device. The test device is composed of an impulse voltage generator 1, a bellows 2, an insulator 3, a crane 4, a three-hole equalizing ball 5, a test piece 6, and a grounding pile 7. Figure 3 The test arrangement is carried out, and the corresponding simulation arrangement is carried out using computing equipment to construct the test device. Busbar connectors and insulator 3 connectors are arranged 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 is connected to the impulse voltage generator 1. Another busbar is arranged vertically, with the upper end connected to the bottom of the corner ball and the other end connected to the test piece 6. Galvanized iron plates are laid flat on the floor of the hall to simulate the ground. During the test, the impulse generator generates a 250 / 2500μs positive polarity operating impulse voltage waveform for impulse testing. When conducting positive polarity operating impulse tests of different gap types, the gap distance can be controlled by a crane 4. At each preset altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m), the ball-plate gap with different preset gap distances (1.00m, 3.00m, 5.00m, 7.00m, 9.00m) was subjected to positive polarity operating impulse discharge tests. During each altitude test, the voltage was directly increased to the voltage obtained in step 1, and then the pressure was continued until the gap broke down, and a 50% operating impulse discharge voltage test value, i.e., a discharge voltage test value, was obtained. The discharge voltage test value corresponding to each preset altitude was obtained in this way.

[0115] Step 203: 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.

[0116] Further, step 203 may include the following sub-steps S31-S34:

[0117] S31. Divide the discharge voltage test values ​​corresponding to all preset altitudes according to the same gap spacing to generate multiple model training sets.

[0118] S32, using the model training set to input the initial shielding ball hardware discharge voltage calculation model to perform parameter calculation and determine the model parameters.

[0119] S33, using model parameters to update the initial shielding ball hardware discharge voltage calculation model to generate an intermediate shielding ball hardware discharge voltage calculation model.

[0120] S34, substituting the preset altitude into the discharge voltage calculation model of the intermediate shielding ball hardware for calculation, and generating a discharge voltage calculation value corresponding to the preset altitude.

[0121] 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:

[0122]

[0123] 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 value of k is 1.78, and for a shielding ball with a diameter of 1.1m and a gap of 3m, the value of k is 1.56; A and B represent altitude factors, and k, A, and B are dimensionless.

[0124] The comparison table of 50% operating impulse discharge voltage of rod-plate air gap at different gap distances at 0m altitude is shown in Table 1.

[0125] Table 1 Discharge voltage comparison table

[0126]

[0127] Substitute the 50% operating impulse discharge voltage test value U50 of the shielding ball hardware at different preset altitudes into the model to determine the model parameters. That is, divide the discharge voltage test values ​​corresponding to all preset altitudes according to the same gap spacing to generate multiple model training sets. Use the model training set to input the initial shielding ball hardware discharge voltage calculation model for parameter calculation to determine the model parameters. Then use 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. Finally, substitute each preset altitude value into the intermediate shielding ball hardware discharge voltage calculation model to obtain the 50% operating impulse discharge voltage calculation value of the shielding ball hardware at each preset altitude, that is, the discharge voltage calculation value.

[0128] 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 the target shielding ball hardware discharge voltage calculation model.

[0129] Further, step 204 may include the following sub-steps S41-S42:

[0130] S41. Calculate the errors between the discharge voltage calculation value and the corresponding discharge voltage test value using a preset error calculation formula to generate a mean absolute error percentage.

[0131] The preset error calculation formula is:

[0132]

[0133] 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 ith altitude point; U i ' represents the calculated value of the discharge voltage at the i-th altitude point.

[0134] S42, updating the intermediate shielding ball hardware discharge voltage calculation model according to the mean absolute error percentage and the preset threshold value, and generating the target shielding ball hardware discharge voltage calculation model.

[0135] Further, step S42 may include the following sub-steps S421-S424:

[0136] S421. Determine whether the mean absolute error percentage is greater than a preset threshold. If so, execute step S422; if not, execute step S424.

[0137] 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.

[0138] S423, using adjustment parameters to modify the model parameters of the intermediate shielding ball hardware discharge voltage calculation model, and generating a target shielding ball hardware discharge voltage calculation model.

[0139] S424, using the intermediate shielding ball hardware discharge voltage calculation model as the target shielding ball hardware discharge voltage calculation model.

[0140] The preset threshold is a critical value corresponding to the error that is set in advance based on actual needs.

[0141] 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, and the error is the average absolute error percentage, that is, the error between the calculated value of the discharge voltage and the corresponding test value of the discharge voltage is calculated using a preset error calculation formula to generate an average absolute error percentage. The validity of the calculation model is determined and corrected by the error between the calculated value and the test value of the 50% operating impulse discharge voltage. That is, it is determined whether the average absolute error percentage is greater than a preset threshold. Specifically: when the average absolute error percentage is within 10%, the parameters of the model are considered to be valid, and the intermediate shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model. When the average absolute error percentage is greater than 10%, the average value of the calculated value and the test value of the 50% operating impulse discharge voltage under each preset gap distance is used as the 50% operating impulse discharge voltage under the preset gap distance and the model parameters are corrected, that is, the model parameters of the intermediate shielding ball hardware discharge voltage calculation model are corrected using the adjustment parameters to generate the target shielding ball hardware discharge voltage calculation model.

[0142] 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.

[0143] 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.

[0144] Step 206: Use the shielding ball hardware discharge voltage to perform nonlinear function fitting to generate a discharge voltage variation relationship.

[0145] 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, and a characteristic curve of the shielding ball hardware discharge voltage changing with the gap distance can be obtained, and a relationship between the 50% operating impulse discharge voltage of the shielding ball hardware and the gap distance, that is, a discharge voltage change relationship, can be obtained. The relationship is:

[0146] U 50％ =ad 2 +bd+c;

[0147] Where U 50％ It represents the 50% operating impulse discharge voltage of the shielding ball fittings, and its unit is kV; d is the gap distance, and its unit is m; a, b and c are parameters.

[0148] Step 207: Obtain the discharge voltage of the equipment end fittings in the converter station valve hall.

[0149] In the embodiment of the present invention, the 50% operating impulse discharge voltage of the end fittings of the converter station valve hall equipment is calculated in combination with 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, i.e., the discharge voltage U50 of the equipment end fittings, is:

[0150]

[0151] Where Uw represents 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.

[0152] 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.

[0153] In the embodiment of the present invention, the air clearance of the shielding ball fitting at the target altitude can be obtained according to the relationship between the 50% operating impulse discharge voltage of the shielding ball fitting and the gap distance. That is, the discharge voltage of the equipment end fitting is substituted into the discharge voltage change relationship to calculate the air clearance corresponding to the shielding ball fitting.

[0154] Specifically, Figure 3 and Figure 4 As shown, the embodiment of the present invention conducts an operating impulse discharge test on a metal shielding ball with a diameter of 1.1m, and predicts its air clearance at an altitude of 3800m. The test voltage waveform adopts a 250 / 2500μs standard operating impulse.

[0155] Step 1: Calculate the boundary voltage when the upper and lower boundaries of the critical volume of the shielding spherical metal fittings coincide at each altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m) respectively. When the upper and lower boundaries coincide, the voltage at this time is the required boundary voltage U c , calculate U at each altitude separately c1 , U c2 , U c3 , U c4 , U c5 , U c6 .

[0156] Step 2: Figure 3The test arrangement is shown in the figure, a shielding ball with a diameter of 1.1m is placed vertically on the ground, and positive polarity operating impulse discharge tests are carried out 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, the voltage is directly increased to the boundary voltage obtained in step one, and then the pressure is continued to be increased until the gap breaks down, so as to obtain a 50% operating impulse discharge voltage test value, i.e., a discharge voltage test value.

[0157] Step 3: Establish a calculation model for the discharge voltage of shielding ball fittings at different altitudes under the same gap distance, namely, an initial calculation model for the discharge voltage of shielding ball fittings. Substitute the test values ​​of the 50% operating impulse discharge voltage of shielding ball fittings at different altitudes into the model to determine the model parameters.

[0158] Step 4: Substitute the preset altitude into the discharge voltage calculation model of the intermediate shielding ball hardware for calculation, and 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, calculate the error between the discharge voltage calculation value and the corresponding discharge voltage test value, and generate the mean absolute error percentage.

[0159] Step 5: Determine the validity of the calculation model through the error between the calculated value and the test value of the 50% operating impulse discharge voltage and make corrections. When the error is within 10%, the parameters of the model are considered valid. When the error is greater than 10%, the average value of the calculated value and the test value of the 50% operating impulse discharge voltage at each gap distance is used as the 50% operating impulse discharge voltage at the gap distance and the model parameters are corrected to determine a new discharge voltage calculation model, that is, the target shielding ball hardware discharge voltage calculation model.

[0160] Step six, 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 varying 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 varying with the gap distance, that is, the discharge voltage variation relationship, can be obtained.

[0161] Step 7. Combined with the typical impulse insulation withstand voltage level inside the converter station valve hall, calculate the 50% operating impulse discharge voltage of the equipment end fittings in the converter station valve hall, 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. According to the relationship between the 50% operating impulse discharge voltage of the shielding ball fitting and the gap distance obtained in step 5, the air clearance of the shielding ball fitting at the target altitude can be obtained. The air clearance of the 1.1m shielding ball fitting in the valve hall of the 800kV converter station at an altitude of 3800m is calculated to be 8.054m.

[0162] Specifically, Figure 3 and Figure 5 As shown, the embodiment of the present invention will conduct an operating impulse discharge test on a 1.1m diameter hardware 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 one to seven, the test can be calculated to obtain a 1.1m diameter shielding ball hardware clearance of 800kV converter station valve hall at an altitude of 4500m. According to the calculations of each embodiment, k = 1.47 ~ 1.78, A = 350.9 ~ 474.7, B = 0.2 ~ 1.5.

[0163] In an embodiment of the present invention, the establishment of the target shielding ball hardware discharge voltage calculation model is based on the operation impulse discharge test at multiple altitude points and multiple gap distances, so that the calculation of the air clearance of the shielding ball hardware is more accurate. The target shielding ball hardware discharge voltage calculation model takes into account the factors of electrode shape and altitude, and introduces a relatively complete database of rod-plate gap operation impulse discharge voltage at 0m altitude, making the model more practical. The characteristic curve of the shielding ball hardware discharge voltage changing with the gap distance and its relationship are obtained by nonlinear function fitting; combined with the typical impulse insulation withstand voltage level inside the converter station valve hall, the air clearance of the shielding ball hardware at the target altitude is calculated. It provides a reference basis for the safety and economy of the design and installation of the converter station valve hall hardware in actual engineering, which can not only accurately obtain the air clearance of the shielding ball hardware, improve the design quality, but also reduce the workload and save a lot of costs. It can be widely used in the selection of the air clearance of the shielding ball hardware in the converter station valve hall.

[0164] See also Figure 6 , Figure 6 This is a structural block diagram of a shielding ball fitting air clearance calculation system provided in Example 3 of the present invention.

[0165] A shielding ball fitting air clearance calculation system provided in Example 3 of the present invention comprises:

[0166] The boundary voltage generating module 601 is used to obtain the structural data of the shielding ball fittings, and use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fittings at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes.

[0167] The discharge voltage test value generating module 602 is used to perform a positive polarity operation impulse discharge test according to the boundary voltage, and generate a discharge voltage test value corresponding to a preset altitude.

[0168] The discharge voltage calculation value generation module 603 is used to use the discharge voltage test value to build a model and perform discharge voltage calculation, and generate a discharge voltage calculation model of the intermediate shielding ball hardware and a discharge voltage calculation value corresponding to a preset altitude.

[0169] 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.

[0170] 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.

[0171] Optionally, the boundary voltage generating module 601 includes:

[0172] The ball-plate model generation module is used to construct the model according to the structural data using multi-physics field simulation software to generate a ball-plate model corresponding to the shielding ball fitting.

[0173] 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 preset voltage application requirements, and generate electrode change data corresponding to the preset altitudes.

[0174] 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.

[0175] The preset upper boundary condition formula is:

[0176]

[0177] 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.

[0178] The default lower boundary condition formula is:

[0179] α = η;

[0180] 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 density of air. The calculation formula for the spatial electric field strength is:

[0181]

[0182]

[0183] In the formula, α is the ionization coefficient; η is the adsorption coefficient; E is the spatial electric field intensity, kV / cm; e represents the natural constant, which is taken as 2.718; δ is the relative density of air, and the calculation formula for the relative density of air is:

[0184]

[0185] 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.

[0186] 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.

[0187] Optionally, the discharge voltage test value generating module 602 includes:

[0188] The test device generation module is used to simulate the test device according to the structural data and generate the test device.

[0189] The discharge voltage test value generation submodule is used to perform impact tests on the test device at multiple preset gap distances using a positive polarity operating impact voltage waveform according to the boundary voltage corresponding to the preset altitude, and generate a discharge voltage test value corresponding to the preset altitude.

[0190] Optionally, the discharge voltage calculation value generating module 603 includes:

[0191] 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.

[0192] 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.

[0193] The calculation model of the initial shielding ball hardware discharge voltage is:

[0194]

[0195] 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, which is 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 altitude factors, and k, A, and B are dimensionless.

[0196] The intermediate shielding ball hardware discharge voltage calculation model generation module is used to update the initial shielding ball hardware discharge voltage calculation model by using model parameters to generate the intermediate shielding ball hardware discharge voltage calculation model.

[0197] 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.

[0198] Optionally, the calculation model generation module 604 includes:

[0199] The mean absolute error percentage generation module is used to calculate the error between the discharge voltage calculation value and the corresponding discharge voltage test value using a preset error calculation formula to generate a mean absolute error percentage.

[0200] The preset error calculation formula is:

[0201]

[0202] 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 ith altitude point; U i ' represents the calculated value of the discharge voltage at the i-th altitude point.

[0203] 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.

[0204] Optionally, the target shielding ball hardware discharge voltage calculation model generation submodule may perform the following steps:

[0205] Determine whether the mean absolute error percentage is greater than a preset threshold;

[0206] If yes, then 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;

[0207] 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;

[0208] If not, the intermediate shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model.

[0209] Optionally, the air clearance generation module 605 includes:

[0210] The shielding ball hardware discharge voltage generation module is used to 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.

[0211] The discharge voltage variation relational expression generation module is used to perform nonlinear function fitting using the shielded ball fitting discharge voltage to generate a discharge voltage variation relational expression.

[0212] The equipment end fitting discharge voltage acquisition module is used to obtain the equipment end fitting discharge voltage of the converter station valve hall.

[0213] 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.

[0214] 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 fittings as in any of the above embodiments.

[0215] 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 a storage space for a program code for executing any method step in the above method. For example, the storage space for the program code may include individual program codes for implementing the various steps in the above method respectively. 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 performs the various steps in the air clearance calculation method for shielded ball fittings described above.

[0216] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method for calculating the air clearance of shielded ball fittings as in any of the above embodiments is implemented.

[0217] Those skilled in the art can 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.

[0218] In the several embodiments provided in the present 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 only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation. For example, 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 interfaces, devices or units, which can be electrical, mechanical or other forms.

[0219] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0220] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0221] 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, in essence, 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, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment 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 codes.

[0222] 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 the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. 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 embodiments of the present invention.

Claims

1. A method for calculating the air clearance of shielding ball fittings, characterized in that: include: Acquire structural data of the shielding ball fitting, and use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fitting at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes; Performing positive polarity operation impulse discharge tests according to the boundary voltages respectively to generate discharge voltage test values ​​corresponding to the preset altitudes; The discharge voltage test value is used to construct a model and perform discharge voltage calculation, to generate a discharge voltage calculation model for an intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude; The intermediate shielding ball hardware discharge voltage calculation model is updated 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; 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; 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 an intermediate shielding ball fitting and a discharge voltage calculation value corresponding to the preset altitude includes: Dividing the discharge voltage test values ​​corresponding to all the preset altitudes according to the same gap spacing to generate multiple model training sets; 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; The calculation model of the discharge voltage of the initial shielding ball hardware is: ； Where U 50 Indicates the discharge voltage test value; It represents the rod-plate positive polarity switching impulse discharge voltage at 0m altitude, 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; A and B represent the altitude factors, and k, A, and B are dimensionless; The model parameters are used to update the initial shielding ball hardware discharge voltage calculation model to generate an intermediate shielding ball hardware discharge voltage calculation model; The preset altitude is substituted into the intermediate shielding ball hardware discharge voltage calculation model for calculation to generate a discharge voltage calculation value corresponding to the preset altitude.

2. The method for calculating the air clearance of shielding ball fittings according to claim 1, characterized in that: The step of using the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fittings at multiple preset altitudes to generate the boundary voltages corresponding to the preset altitudes includes: Using multi-physics field simulation software to construct a model according to the structural data, and generating a ball-plate model corresponding to the shielding ball fitting; According to the preset voltage application requirements, the ball electrode voltage simulations at multiple preset altitudes are respectively performed on the ball-plate model to generate electrode change data corresponding to the preset altitudes; Substituting the electrode change data into a preset upper boundary condition formula and a preset lower boundary condition formula to perform boundary calculations, thereby generating upper boundary data and lower boundary data corresponding to the electrode change data; The preset upper boundary condition formula is: ； In the formula, represents the electrode surface; represents the distance between the upper boundary and the electrode surface; 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; The preset lower boundary condition formula is: ； 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 density of air. The calculation formula for the spatial electric field strength is: ； ； In the formula, α is the ionization coefficient; η is the adsorption coefficient; E is the spatial electric field intensity, kV / cm; e represents the natural constant, which is 2.718; is the relative density of air, and the calculation formula of the relative density of air is: ； In the formula, is the relative density of air; t is the ambient temperature at each altitude, in °C; p is the atmospheric pressure at each altitude; Indicates standard atmospheric pressure, with a value of 101 kPa; 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.

3. The method for calculating the air clearance of shielding ball fittings according to claim 1, characterized in that: 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: Simulating the test device according to the structural data to generate the test device; 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.

4. The method for calculating the air clearance of shielding ball fittings according to claim 1, characterized in that: The step of updating the intermediate shielding ball hardware discharge voltage calculation model according to the error between the discharge voltage calculated value and the corresponding discharge voltage test value, and generating a target shielding ball hardware discharge voltage calculation model comprises; The errors between the discharge voltage calculation value and the corresponding discharge voltage test value are calculated using a preset error calculation formula to generate a mean absolute error percentage; The preset error calculation formula is: ； In the formula, represents the mean absolute error percentage; n represents the number of test altitude points; i takes values ​​of 1, 2, …, n; Indicates the discharge voltage test value at the ith altitude point; represents the calculated value of the discharge voltage at the i-th altitude point; The intermediate shielding ball hardware discharge voltage calculation model is updated according to the mean absolute error percentage and the preset threshold value to generate a target shielding ball hardware discharge voltage calculation model.

5. The method for calculating the air clearance of shielding ball fittings according to claim 4, characterized in that: The step of updating the intermediate shielding ball hardware discharge voltage calculation model according to the mean absolute error percentage and the preset threshold to generate the target shielding ball hardware discharge voltage calculation model includes: Determine whether the mean absolute error percentage is greater than a preset threshold; If yes, then 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 an adjustment parameter; The adjustment parameters are used 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; If not, the intermediate shielding ball hardware discharge voltage calculation model is used as the target shielding ball hardware discharge voltage calculation model.

6. The method for calculating the air clearance of shielding ball fittings according to claim 1, characterized in that: 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 comprises: The discharge voltage of the shielding ball hardware at different gap distances under the target altitude corresponding to the shielding ball hardware is obtained through the target shielding ball hardware discharge voltage calculation model, and a plurality of shielding ball hardware discharge voltages are generated; The discharge voltage of the shielding ball hardware is used to perform nonlinear function fitting to generate a discharge voltage variation relationship; Obtain the discharge voltage of the equipment end fittings in the converter station valve hall; 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.

7. A shielding ball fitting air clearance calculation system, characterized in that: include: A boundary voltage generating module, used to obtain structural data of the shielding ball fittings, and use the structural data to respectively calculate the voltages corresponding to the overlap of the boundaries of the shielding ball fittings at multiple preset altitudes, and generate boundary voltages corresponding to the preset altitudes; A discharge voltage test value generating module, used 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; A discharge voltage calculation value generation module, used to use the discharge voltage test value to build 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; A calculation model generation module, used to update the discharge voltage calculation model of the intermediate shielding ball hardware 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; An air clearance generation module, 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; The discharge voltage calculation value generation module includes: A model training set generation module, used to divide the discharge voltage test values ​​corresponding to all the preset altitudes according to the same gap spacing to generate multiple model training sets; A model parameter determination module, 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; The calculation model of the discharge voltage of the initial shielding ball hardware is: ； Where U 50 Indicates the discharge voltage test value; It represents the rod-plate positive polarity switching impulse discharge voltage at 0m altitude, 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; A and B represent the altitude factors, and k, A, and B are dimensionless; An intermediate shielding ball hardware discharge voltage calculation model generation module is used to update the initial shielding ball hardware discharge voltage calculation model using the model parameters to generate an intermediate shielding ball hardware discharge voltage calculation model; The discharge voltage calculation value generation module is used to substitute the preset altitude into the discharge voltage calculation model of the intermediate shielding ball hardware for calculation, so as to generate a discharge voltage calculation value corresponding to the preset altitude.

8. An electronic device, characterized in that: It comprises a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the method for calculating the air clearance of shielded ball fittings as described in any one of claims 1 to 6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the method for calculating the air clearance of shielding ball fittings as described in any one of claims 1 to 6 is implemented.

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