A method, system, device and medium for calculating the discharge voltage of end fittings

Abstract

The present invention discloses a method, system, device and medium for calculating the discharge voltage of end fittings, relating to the technical field of fittings. The finite element method is used to calculate the electric field distribution of structural data at multiple preset altitudes and multiple preset gap distances, and electric field distribution data is generated. Based on the electric field distribution data, a positive polarity switching impulse discharge test is carried out to determine the streamer critical inception voltage and the positive polarity switching impulse discharge voltage of the fittings. According to the streamer critical inception voltage, positive polarity switching impulse tests are respectively carried out on the intermediate altitudes corresponding to each preset altitude to generate discharge voltage test values. Based on the positive polarity switching impulse discharge voltage of the fittings and the discharge voltage test values, the model is updated to generate a target calculation model for the discharge voltage of the end fittings. The discharge voltage of the end fittings is calculated through the target calculation model for the discharge voltage of the end fittings. The streamer critical inception voltage is calculated by finite element simulation, and the voltage is applied starting from this voltage, reducing the test time and economic cost.

Description

Technical Field

[0001] The present invention relates to the technical field of fittings, and particularly to a method, system, device and medium for calculating the discharge voltage of end fittings. Background Art

[0002] The equipment in the valve hall of a converter station is an important part of the power system and is used to achieve the transmission and conversion of electrical energy. The discharge voltage of the end fittings of the equipment in the valve hall of a converter station is one of the important indicators for evaluating the equipment status and ensuring the safe operation of the equipment.

[0003] However, different altitudes will cause changes in environmental conditions such as atmospheric pressure and temperature, thus affecting the accurate measurement and judgment of the discharge voltage of end fittings, which brings troubles to equipment control and operation. The current solutions often measure environmental parameters such as atmospheric pressure and temperature through sensors and then perform compensation or correction. However, this method requires the installation and maintenance of sensors, increasing the equipment cost and the operation complexity. Summary of the Invention

[0004] The present invention provides a method, system, device and medium for calculating the discharge voltage of end fittings, and solves the technical problem that the existing method for calculating the discharge voltage of end fittings measures environmental parameters such as atmospheric pressure and temperature through sensors, which requires the installation and maintenance of sensors, increases the equipment cost, and has a high operation complexity.

[0005] A method for calculating the discharge voltage of end fittings provided by the present invention includes:

[0006] Obtain the structural data and the actual altitude of the end fittings, and use the finite element method to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances, and generate electric field distribution data;

[0007] Conduct a positive polarity switching impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the positive polarity switching impulse discharge voltage of the fitting;

[0008] Conduct positive polarity switching impulse tests on the intermediate altitudes corresponding to each of the preset altitudes according to the streamer critical inception voltage, and generate discharge voltage test values;

[0009] Update the initial fitting discharge voltage calculation model according to the positive polarity switching impulse discharge voltage of the fitting and the discharge voltage test values to generate a target fitting discharge voltage calculation model;

[0010] Substitute the actual altitude into the target fitting discharge voltage calculation model for voltage calculation to generate the discharge voltage corresponding to the end fitting.

[0011] Optionally, the step of performing a positive polarity switching impulse discharge test based on the electric field distribution data and determining the streamer critical inception voltage and the fitting positive polarity switching impulse discharge voltage of the fitting includes:

[0012] Substituting the electric field distribution data into a preset photoionization model to calculate the critical inception voltage value of the discharge streamer of the end fitting, and generating the streamer critical inception voltage;

[0013] The photoionization criterion corresponding to the preset photoionization model is:

[0014]

[0015] In the formula, r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionospheric boundary, determined by α = η; α is the ionization coefficient; η is the attachment coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor;

[0016] Starting from the streamer critical inception voltage, applying voltage to the test device corresponding to the end fitting to perform a positive polarity switching impulse discharge test, and generating the fitting positive polarity switching impulse discharge voltage.

[0017] Optionally, the step of updating the initial fitting discharge voltage calculation model according to the fitting positive polarity switching impulse discharge voltage and the discharge voltage test value to generate a target fitting discharge voltage calculation model includes:

[0018] Selecting the discharge voltage corresponding to the gap distance of the fitting positive polarity switching impulse discharge voltage from a preset rod-plate positive polarity switching impulse discharge voltage database to generate the gap distance discharge voltage;

[0019] Substituting the gap distance discharge voltage and the fitting positive polarity switching impulse discharge voltage into the initial fitting discharge voltage calculation model to calculate the model parameters, and generating the model parameters;

[0020] The initial fitting discharge voltage calculation model is:

[0021]

[0022] Among them, U is the discharge voltage; U0 is the rod-plate positive polarity switching impulse discharge voltage at an altitude of 0 m, with the unit of kV; H is the altitude, with the unit of m; k1 is the shape factor, k2 is the altitude factor, k1 and k2 are dimensionless, and e takes 2.7183;

[0023] Updating the initial fitting discharge voltage calculation model with the model parameters to generate an intermediate fitting discharge voltage calculation model;

[0024] Update the calculation model of the intermediate fitting discharge voltage according to the test value of the discharge voltage to generate a target fitting discharge voltage calculation model.

[0025] Optionally, the step of updating the calculation model of the intermediate fitting discharge voltage according to the test value of the discharge voltage to generate a target fitting discharge voltage calculation model includes:

[0026] Substitute the intermediate altitude corresponding to each preset altitude into the calculation model of the intermediate fitting discharge voltage to calculate the discharge voltage, and generate a discharge voltage calculation value;

[0027] Substitute the discharge voltage calculation value and the test value of the discharge voltage into a preset error calculation formula to calculate the error, and generate a relative root mean square error;

[0028] The preset error calculation formula is:

[0029]

[0030] In the formula, δ is the relative root mean square error; n represents the total number of intermediate altitudes; i takes values of 1, 2... n; U i is the test value of the discharge voltage at the i-th intermediate altitude; U' i is the calculated value of the discharge voltage at the i-th intermediate altitude;

[0031] Update the calculation model of the intermediate fitting discharge voltage according to the relative root mean square error and a preset error threshold to generate a target fitting discharge voltage calculation model.

[0032] Optionally, the step of updating the calculation model of the intermediate fitting discharge voltage according to the relative root mean square error and a preset error threshold to generate a target fitting discharge voltage calculation model includes:

[0033] Judge whether the relative root mean square error is greater than the preset error threshold;

[0034] If so, take the average value of the discharge voltage calculation value and the test value of the discharge voltage as the corresponding switching impulse discharge voltage;

[0035] Substitute the switching impulse discharge voltage into the calculation model of the intermediate fitting discharge voltage to correct the model parameters, and generate a target fitting discharge voltage calculation model;

[0036] If not, take the calculation model of the intermediate fitting discharge voltage as the target fitting discharge voltage calculation model.

[0037] The present invention also provides an end fitting discharge voltage calculation system, including:

[0038] An electric field distribution data generation module, configured to obtain the structural data of the end fitting and the actual altitude, and calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances by using the finite element method, so as to generate electric field distribution data;

[0039] A streamer critical inception voltage and fitting positive polarity switching impulse discharge voltage determination module, configured to perform a positive polarity switching impulse discharge test according to the electric field distribution data, and determine the streamer critical inception voltage and the fitting positive polarity switching impulse discharge voltage;

[0040] A discharge voltage test value generation module, configured to perform a positive polarity switching impulse test on the intermediate altitude corresponding to each of the preset altitudes according to the streamer critical inception voltage, so as to generate a discharge voltage test value;

[0041] A target fitting discharge voltage calculation model generation module, configured to update an initial fitting discharge voltage calculation model according to the fitting positive polarity switching impulse discharge voltage and the discharge voltage test value, so as to generate a target fitting discharge voltage calculation model;

[0042] A discharge voltage generation module, configured to substitute the actual altitude into the target fitting discharge voltage calculation model for voltage calculation, so as to generate the discharge voltage corresponding to the end fitting.

[0043] Optionally, the streamer critical inception voltage and fitting positive polarity switching impulse discharge voltage determination module includes:

[0044] A streamer critical inception voltage generation module, configured to substitute the electric field distribution data into a preset photoionization model to calculate the streamer critical inception voltage value of the end fitting, so as to generate a streamer critical inception voltage;

[0045] The photoionization criterion corresponding to the preset photoionization model is:

[0046]

[0047] In the formula, r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionization layer boundary, which is determined by α = η; α is the ionization coefficient; η is the adsorption coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor;

[0048] A fitting positive polarity switching impulse discharge voltage generation module, configured to perform a positive polarity switching impulse discharge test on the test device corresponding to the end fitting starting from the streamer critical inception voltage, so as to generate a fitting positive polarity switching impulse discharge voltage.

[0049] Optionally, the target fitting discharge voltage calculation model generation module includes:

[0050] A gap distance discharge voltage generation module, configured to select a gap distance discharge voltage corresponding to the positive polarity switching impulse discharge voltage of the fitting from a preset database of positive polarity switching impulse discharge voltages of a rod-plate, and generate a gap distance discharge voltage;

[0051] A model parameter generation module, configured to substitute the gap distance discharge voltage and the positive polarity switching impulse discharge voltage of the fitting into an initial fitting discharge voltage calculation model to perform model parameter calculation, and generate model parameters;

[0052] The initial fitting discharge voltage calculation model is:

[0053]

[0054] where U is the discharge voltage; U0 is the positive polarity switching impulse discharge voltage of a rod-plate at an altitude of 0 m, and its unit is kV; H is the altitude, and its unit is m; k1 is a shape factor, k2 is an altitude factor, k1 and k2 are dimensionless, and e takes 2.7183;

[0055] An intermediate fitting discharge voltage calculation model generation module, configured to update the initial fitting discharge voltage calculation model by using the model parameters, and generate an intermediate fitting discharge voltage calculation model;

[0056] A target fitting discharge voltage calculation model generation sub-module, configured to update the intermediate fitting discharge voltage calculation model according to the discharge voltage test value, and generate a target fitting discharge voltage calculation model.

[0057] The present invention further provides an electronic device, including a memory and a processor. 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 implementing the end fitting discharge voltage calculation method as described in any one of the above.

[0058] The present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed, the end fitting discharge voltage calculation method as described in any one of the above is implemented.

[0059] It can be seen from the above technical solutions that the present invention has the following advantages:

[0060] The present invention obtains the structural data of the end fitting and the actual altitude, calculates the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances by using the finite element method, and generates electric field distribution data. Based on the electric field distribution data, a positive polarity switching impulse discharge test is carried out to determine the streamer critical inception voltage and the positive polarity switching impulse discharge voltage of the fitting. According to the streamer critical inception voltage, positive polarity switching impulse tests are respectively carried out on the intermediate altitudes corresponding to each preset altitude to generate discharge voltage test values. Based on the positive polarity switching impulse discharge voltage of the fitting and the discharge voltage test values, the initial calculation model of the fitting discharge voltage is updated to generate a target calculation model of the fitting discharge voltage. The actual altitude is substituted into the target calculation model of the fitting discharge voltage for voltage calculation to generate the discharge voltage corresponding to the end fitting. It solves the technical problem that the existing calculation method of the end fitting discharge voltage measures environmental parameters such as atmospheric pressure and temperature through sensors, which requires the installation and maintenance of sensors, increases the equipment cost, and has high operation complexity. The streamer critical inception voltage is calculated by finite element simulation, and the voltage is applied starting from this voltage, reducing the test time and economic cost. The construction of the model takes into account the gap structure and altitude factors, making the calculation of the end fitting discharge voltage more accurate. Brief Description of the Drawings

[0061] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0062] Figure 1 It is a flowchart of the steps of a method for calculating the discharge voltage of an end fitting provided in Embodiment 1 of the present invention;

[0063] Figure 2 It is a flowchart of the steps of a method for calculating the discharge voltage of an end fitting provided in Embodiment 2 of the present invention;

[0064] Figure 3 It is an arrangement diagram of a positive polarity standard switching impulse discharge test provided in Embodiment 2 of the present invention;

[0065] Figure 4 It is a characteristic curve diagram of the discharge voltage U - altitude H of a 1.6 m diameter ring-shaped grading ring vertically facing the ground with a 3 m gap provided in Embodiment 2 of the present invention;

[0066] Figure 5 It is a characteristic curve diagram of the discharge voltage U - altitude H of a 1.6 m diameter ring-shaped grading ring vertically facing the ground with a 4 m gap provided in Embodiment 2 of the present invention;

[0067] Figure 6 It is the characteristic curve of the discharge voltage U - altitude H of the 1.6m diameter grading ring vertically facing the ground with a 6m gap provided in the second embodiment of the present invention;

[0068] Figure 7 It is the characteristic curve of the discharge voltage U - altitude H of the 2.6m diameter grading ring vertically facing the ground with a 1.5m gap provided in the second embodiment of the present invention;

[0069] Figure 8 It is the structural block diagram of a discharge voltage calculation system for end fittings provided in the third embodiment of the present invention.

[0070] Figure 3 The reference numerals in

[0071] are: 1. impulse voltage generator; 2. bellows; 3. insulator; 4. crane; 5. three - hole grading sphere; 6. test sample; 7. grounding pile.

[0072] The embodiments of the present invention provide a method, system, device and medium for calculating the discharge voltage of end fittings, which are used to solve the technical problems that the existing method for calculating the discharge voltage of end fittings measures environmental parameters such as atmospheric pressure and temperature through sensors, requires the installation and maintenance of sensors, increases the equipment cost, and has high operation complexity.

[0073] To make the objectives, features, and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described below are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0074] Please refer to Figure 1 , Figure 1 It is the step flowchart of a method for calculating the discharge voltage of end fittings provided in the first embodiment of the present invention.

[0075] A method for calculating the discharge voltage of end fittings provided in the first example of the present invention includes:

[0076] Step 101: Obtain the structural data of the end fitting and the actual altitude, and use the finite element method to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances, and generate electric field distribution data.

[0077] The preset altitude refers to the altitude set in advance, usually set to 0m, 1000m, 2000m, 3000m, 4000m, 5000m. The preset gap distance refers to the spacing distance set as needed.

[0078] In the embodiment of the present invention, the finite element method is used to obtain the electric field distribution of the end fitting at different gap distances at each altitude (0m, 1000m, 2000m, 3000m, 4000m, 5000m), so as to obtain the electric field distribution data.

[0079] Step 102: Perform a positive polarity operating impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the positive polarity operating impulse discharge voltage of the fitting.

[0080] In the embodiment of the present invention, the electric field distribution data is substituted into the preset photoionization model to calculate the streamer critical inception voltage value of the end fitting, and the streamer critical inception voltage is generated. Starting from the streamer critical inception voltage, a positive polarity operating impulse discharge test is performed on the test device corresponding to the end fitting to generate the positive polarity operating impulse discharge voltage of the fitting.

[0081] Step 103: Perform a positive polarity operating impulse test on the intermediate altitude corresponding to each preset altitude according to the streamer critical inception voltage to generate the test value of the discharge voltage.

[0082] In the embodiment of the present invention, positive polarity operating impulse tests are performed according to the intermediate heights (500m, 1500m, 2500m, 3500m, 4500m) between each altitude to obtain the test values of each discharge voltage.

[0083] Step 104: Update the initial fitting discharge voltage calculation model according to the positive polarity operating impulse discharge voltage of the fitting and the test value of the discharge voltage to generate the target fitting discharge voltage calculation model.

[0084] In the embodiment of the present invention, the discharge voltage corresponding to the gap distance of the positive polarity operating impulse discharge voltage of the fitting is selected from the preset rod-plate positive polarity operating impulse discharge voltage database to generate the gap distance discharge voltage. The gap distance discharge voltage and the positive polarity operating impulse discharge voltage of the fitting are substituted into the initial fitting discharge voltage calculation model to calculate the model parameters, and the model parameters are generated. The initial fitting discharge voltage calculation model is updated using the model parameters to generate the intermediate fitting discharge voltage calculation model. The intermediate fitting discharge voltage calculation model is updated based on the test value of the discharge voltage to generate the target fitting discharge voltage calculation model.

[0085] Step 105: Substitute the actual altitude into the target fitting discharge voltage calculation model for voltage calculation to generate the discharge voltage corresponding to the end fitting.

[0086] In an embodiment of the present invention, after the target fitting discharge voltage calculation model corresponding to the end fitting is constructed, the actual altitude corresponding to the end fitting is substituted into the target fitting discharge voltage calculation model for voltage calculation, and the discharge voltage corresponding to the end fitting can be calculated.

[0087] In an embodiment of the present invention, by obtaining the structural data and the actual altitude of the end fitting, the finite element method is used to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances, and electric field distribution data is generated. Based on the electric field distribution data, a positive polarity switching impulse discharge test is carried out to determine the streamer critical inception voltage and the fitting positive polarity switching impulse discharge voltage. According to the streamer critical inception voltage, positive polarity switching impulse tests are respectively carried out on the intermediate altitudes corresponding to each preset altitude to generate discharge voltage test values. Based on the fitting positive polarity switching impulse discharge voltage and the discharge voltage test values, the initial fitting discharge voltage calculation model is updated to generate a target fitting discharge voltage calculation model. The actual altitude is substituted into the target fitting discharge voltage calculation model for voltage calculation to generate the discharge voltage corresponding to the end fitting. This solves the technical problem that the existing method for calculating the discharge voltage of the end fitting measures environmental parameters such as atmospheric pressure and temperature through sensors, which requires the installation and maintenance of sensors, increases the equipment cost, and has high operation complexity. The streamer critical inception voltage is calculated by finite element simulation, and the voltage is applied starting from this voltage, reducing the test time and economic cost. The construction of the model takes into account the gap structure and altitude factors, making the calculation of the discharge voltage of the end fitting more accurate.

[0088] Please refer to Figure 2 , Figure 2 which is the step flowchart of a method for calculating the discharge voltage of an end fitting provided in the second embodiment of the present invention.

[0089] Another method for calculating the discharge voltage of an end fitting provided in the second embodiment of the present invention includes:

[0090] Step 201: Obtain the structural data and the actual altitude of the end fitting, and use the finite element method to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances, and generate electric field distribution data.

[0091] In an embodiment of the present invention, the specific implementation process of step 201 is similar to that of step 101 and will not be elaborated here.

[0092] Step 202: Perform a positive polarity switching impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the fitting positive polarity switching impulse discharge voltage.

[0093] Further, step 202 may include the following sub-steps S11 - S12:

[0094] S11. Substitute the electric field distribution data into a preset photoionization model to calculate the critical initial voltage value of the streamer discharge of the end fitting, and generate the critical initial voltage of the streamer.

[0095] S12. Starting from the critical initial voltage of the streamer, apply a positive polarity impulse discharge test to the test device corresponding to the end fitting to generate the positive polarity impulse discharge voltage of the fitting.

[0096] 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 corrugated pipe 2, an insulator 3, a crane 4, a three-hole grading sphere 5, a test sample 6, and a grounding pile 7, that is, as Figure 3 Conduct test layout, and use a computing device to perform corresponding simulation layout, so as to construct the test device. A bus connector and an insulator 3 connector 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 bus is vertically arranged, the upper end is connected to the bottom end of the corner ball, and the other end is connected to the test sample 6. Galvanized iron sheets are laid flat on the hall floor to simulate the ground. During the test process, the impulse generator generates a standard positive polarity impulse voltage waveform to conduct the impulse test.

[0097] Use the preset photoionization model combined with the electric field distribution data to calculate the critical initial voltage value of the streamer discharge of the end fitting. The photoionization criterion is as follows. When the following formula is equal to 1, the critical initial voltage of the streamer can be obtained.

[0098]

[0099] In the formula, r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionosphere boundary, which is determined by α = η; α is the ionization coefficient; η is the adsorption coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor.

[0100] In the above formula, the values of α, η, and μ are related to the electric field strength and air density, and their calculation formulas are as follows:

[0101]

[0102]

[0103] μ = δμ0;

[0104] In the formula, E is the spatial electric field strength, kV / cm; δ is the relative air density, and the calculation formula is:

[0105]

[0106] Wherein, t represents the test ambient temperature; p represents the test ambient atmospheric pressure; p0 represents the standard atmospheric pressure.

[0107] Wherein the photon absorption coefficient μ is proportional to the relative air density, and μ0 is the photon absorption coefficient under standard atmospheric conditions.

[0108] At each altitude, starting from the streamer critical inception voltage, a positive polarity switching impulse discharge test is carried out by applying voltage to obtain the positive polarity switching impulse discharge voltage of the fitting.

[0109] Step 203: Conduct positive polarity switching impulse tests on the intermediate altitudes corresponding to each preset altitude according to the streamer critical inception voltage to generate discharge voltage test values.

[0110] In the embodiment of the present invention, the specific implementation process of step 203 is similar to that of step 103, and will not be elaborated here.

[0111] Step 204: Select the discharge voltage corresponding to the gap distance of the positive polarity switching impulse discharge voltage of the fitting from the preset rod-plate positive polarity switching impulse discharge voltage database to generate the gap distance discharge voltage.

[0112] The preset rod-plate positive polarity switching impulse discharge voltage database refers to a database including the rod-plate positive polarity switching impulse discharge voltage data at an altitude of 0m.

[0113] The 50% switching impulse discharge voltage comparison table of the rod-plate air gap at different gap distances at an altitude of 0m is shown in Table 1.

[0114] Table 1 Comparison table of rod-plate positive polarity switching impulse discharge voltage at an altitude of 0m

[0115]

[0116] In the embodiment of the present invention, select the discharge voltage corresponding to the gap distance of the positive polarity switching impulse discharge voltage of the fitting from the preset rod-plate positive polarity switching impulse discharge voltage database to generate the gap distance discharge voltage.

[0117] Step 205: Substitute the gap distance discharge voltage and the positive polarity switching impulse discharge voltage of the fitting into the initial fitting discharge voltage calculation model to calculate the model parameters and generate the model parameters.

[0118] In the embodiment of the present invention, a fitting discharge voltage calculation model considering the influence of altitude with the rod-plate discharge voltage at 0m as the reference is established. Wherein, U is the discharge voltage; U0 is the rod-plate positive polarity switching impulse discharge voltage at an altitude of 0m, and its unit is kV; H is the altitude, and its unit is m; k1 is the shape factor, k2 is the altitude factor, k1 and k2 are dimensionless, and e takes 2.7183.

[0119] The breakdown voltages of the fitting at each altitude under positive polarity switching impulse are corresponded to the breakdown voltages of the rod-plane gap at 0 m altitude in the database, and the breakdown voltages at the corresponding gap distances are substituted into the calculation model to determine the specific values of the parameters k1 and k2 of the calculation model, so as to obtain the model parameters.

[0120] Step 206: Update the initial fitting breakdown voltage calculation model with the model parameters to generate an intermediate fitting breakdown voltage calculation model.

[0121] In the embodiment of the present invention, the calculated model parameters are used to update the initial fitting breakdown voltage calculation model, so as to obtain an intermediate fitting breakdown voltage calculation model.

[0122] Step 207: Update the intermediate fitting breakdown voltage calculation model according to the test values of the breakdown voltage to generate a target fitting breakdown voltage calculation model.

[0123] Further, step 207 may include the following sub-steps S21 - S23:

[0124] S21: Substitute the intermediate altitudes corresponding to each preset altitude into the intermediate fitting breakdown voltage calculation model to calculate the breakdown voltage and generate a breakdown voltage calculation value.

[0125] S22: Substitute the breakdown voltage calculation value and the test value of the breakdown voltage into a preset error calculation formula to calculate the error and generate a relative root mean square error.

[0126] The preset error calculation formula is:

[0127]

[0128] In the formula, δ is the relative root mean square error; n represents the total number of intermediate altitudes; i takes values of 1, 2... n; U i is the test value of the breakdown voltage at the i-th intermediate altitude; U' i is the breakdown voltage calculation value at the i-th intermediate altitude.

[0129] S23: Update the intermediate fitting breakdown voltage calculation model according to the relative root mean square error and a preset error threshold to generate a target fitting breakdown voltage calculation model.

[0130] Further, step S23 may include the following sub-steps S231 - S234:

[0131] S231: Determine whether the relative root mean square error is greater than the preset error threshold. If so, execute step S232; if not, execute step S234.

[0132] S232. Use the average value of the calculated discharge voltage and the tested discharge voltage as the corresponding switching impulse discharge voltage.

[0133] S233. Substitute the switching impulse discharge voltage into the intermediate fitting discharge voltage calculation model to correct the model parameters and generate the target fitting discharge voltage calculation model.

[0134] S234. Use the intermediate fitting discharge voltage calculation model as the target fitting discharge voltage calculation model.

[0135] The preset error threshold is 10%.

[0136] In the embodiment of the present invention, substitute the intermediate altitude between each altitude into the calculation model to calculate the error with the tested value of the intermediate altitude to determine the effectiveness of the calculation model and make corrections. Specifically, first, substitute the intermediate altitude corresponding to each preset altitude into the intermediate fitting discharge voltage calculation model to calculate the discharge voltage and generate the calculated discharge voltage value. Then, substitute the calculated discharge voltage value and the tested discharge voltage value into the preset error calculation formula to calculate the error and generate the relative root mean square error. Finally, update the intermediate fitting discharge voltage calculation model based on the relative root mean square error and the preset error threshold to generate the target fitting discharge voltage calculation model. That is, if the relative root mean square error is less than or equal to 10%, then adopt this calculation model, that is, use the intermediate fitting discharge voltage calculation model as the target fitting discharge voltage calculation model. If the relative root mean square error is greater than 10%, then use the average value between the calculated discharge voltage value and the tested discharge voltage value as the 50% switching impulse discharge voltage at this gap distance, obtain the corrected shape factor k1 and altitude factor k2, substitute them into the intermediate fitting discharge voltage calculation model, and finally obtain the corrected calculation model, that is, the target fitting discharge voltage calculation model.

[0137] Step 208. Substitute the actual altitude into the target fitting discharge voltage calculation model to calculate the voltage and generate the discharge voltage corresponding to the end fitting.

[0138] In the embodiment of the present invention, the specific implementation process of step 208 is similar to that of step 105 and will not be elaborated here.

[0139] Specifically, as Figure 3 and Figure 4 shown, conduct the switching impulse discharge test on the 1.6m diameter equalizing ring vertically facing the ground at 3m according to the above steps, and the test voltage waveform adopts the standard switching impulse voltage. Obtain the characteristic curve of the discharge voltage U - altitude H of the 1.6m diameter equalizing ring vertically facing the ground at 3m gap.

[0140] As Figure 3 and Figure 5As shown, the switching impulse discharge test will be carried out on the grading ring with a ring diameter of 1.6 m vertically 4 m above the ground according to the above steps, and the test voltage waveform will adopt the standard switching impulse voltage. The characteristic curve of the discharge voltage U - altitude H of the gap between the grading ring with a ring diameter of 1.6 m vertically 4 m above the ground is obtained.

[0141] As Figure 3 and Figure 6 shown, the switching impulse discharge test will be carried out on the grading ring with a ring diameter of 1.6 m vertically 6 m above the ground according to the above steps, and the test voltage waveform will adopt the standard switching impulse voltage. The characteristic curve of the discharge voltage U - altitude H of the gap between the grading ring with a ring diameter of 1.6 m vertically 6 m above the ground is obtained.

[0142] As Figure 3 and Figure 7 shown, the switching impulse discharge test will be carried out on the grading ring with a ring diameter of 2.6 m vertically 1.5 m above the ground according to the above steps, and the test voltage waveform will adopt the standard switching impulse voltage. The characteristic curve of the discharge voltage U - altitude H of the gap between the grading ring with a ring diameter of 2.6 m vertically 1.5 m above the ground is obtained.

[0143] Through the above experiments, it can be calculated that k1 = 1.17 - 2.15 and k2 = 0.53 - 0.88.

[0144] In the embodiments of the present invention, by establishing a calculation formula for the discharge voltage corresponding to different gap types and gap distances, the discharge voltage values at different altitudes can be calculated, thereby achieving calibration. In this method, the photoionization criterion is used in combination with finite element simulation to calculate the critical onset voltage of streamers, and the voltage is applied starting from this voltage, reducing the test time and economic costs. For low-altitude areas, the rod-plate voltage is used as the calibration reference value. The rod-plate voltage is a kind of data that is common and widely collected, and can be obtained from the operation records and test data of many valve hall equipment in converter stations. Since the environmental conditions such as atmospheric pressure and temperature in low-altitude areas are relatively stable compared with other areas, the rod-plate voltage can be used as a reliable reference value for calibration. Compared with the traditional calibration method based on sensor measurement, the advantage of the present invention is that there is no need to install and maintain additional sensor devices, but the rod-plate voltage in the existing operation records and test data is used as the calibration reference. In this way, not only the problems of sensor cost and maintenance are avoided, but also a wide range of data sources can be used for calibration, improving the feasibility and universality of the calculation method. The model is established based on the rod-plate gap discharge voltage database at 0m altitude, considering the gap structure and altitude factors, making the calculation of the discharge voltage of fittings more accurate. The photoionization criterion is used in combination with finite element simulation to calculate the critical onset voltage of streamers, and the voltage is applied starting from this voltage, reducing the test time and economic costs. Taking the rod-plate discharge voltage at 0m with richer and more stable data as the reference, the work of the test at 0m altitude is reduced. It meets the reference basis for the safety and economy of the design and installation of the end fittings of the valve hall equipment in the actual project. It can not only accurately obtain the discharge voltage of various fittings in high-altitude areas, but also reduce the workload and save a large amount of costs.

[0145] Please refer to Figure 8 , Figure 8 which is the structural block diagram of a system for calculating the discharge voltage of end fittings provided in Embodiment 3 of the present invention.

[0146] A system for calculating the discharge voltage of end fittings provided in Embodiment 3 of the present invention includes:

[0147] An electric field distribution data generation module 801, configured to obtain the structural data of the end fittings and the actual altitude, and calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances by using the finite element method, and generate electric field distribution data.

[0148] A critical onset voltage of streamers and a positive polarity switching impulse discharge voltage determination module 802 of the fitting, configured to perform a positive polarity switching impulse discharge test according to the electric field distribution data, and determine the critical onset voltage of streamers and the positive polarity switching impulse discharge voltage of the fitting.

[0149] The discharge voltage test value generation module 803 is configured to perform a positive polarity switching impulse test on each intermediate altitude corresponding to a preset altitude according to the streamer critical inception voltage, and generate a discharge voltage test value.

[0150] The target fitting discharge voltage calculation model generation module 804 is configured to update the initial fitting discharge voltage calculation model based on the fitting positive polarity switching impulse discharge voltage and the discharge voltage test value, and generate a target fitting discharge voltage calculation model.

[0151] The discharge voltage generation module 805 is configured to substitute the actual altitude into the target fitting discharge voltage calculation model for voltage calculation, and generate the discharge voltage corresponding to the end fitting.

[0152] Optionally, the streamer critical inception voltage and fitting positive polarity switching impulse discharge voltage determination module 802 includes:

[0153] The streamer critical inception voltage generation module is configured to substitute the electric field distribution data into a preset photoionization model to calculate the streamer critical inception voltage value of the end fitting, and generate a streamer critical inception voltage.

[0154] The photoionization criterion corresponding to the preset photoionization model is:

[0155]

[0156] In the formula, r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionosphere boundary, which is determined by α = η; α is the ionization coefficient; η is the adsorption coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor.

[0157] The fitting positive polarity switching impulse discharge voltage generation module is configured to perform a positive polarity switching impulse discharge test on the test device corresponding to the end fitting starting from the streamer critical inception voltage, and generate a fitting positive polarity switching impulse discharge voltage.

[0158] Optionally, the target fitting discharge voltage calculation model generation module 804 includes:

[0159] The gap distance discharge voltage generation module is configured to select the gap distance discharge voltage corresponding to the fitting positive polarity switching impulse discharge voltage from a preset rod-plate positive polarity switching impulse discharge voltage database, and generate a gap distance discharge voltage.

[0160] The model parameter generation module is configured to substitute the gap distance discharge voltage and the fitting positive polarity switching impulse discharge voltage into the initial fitting discharge voltage calculation model for model parameter calculation, and generate model parameters.

[0161] The calculation model of the discharge voltage of the initial fitting is as follows:

[0162]

[0163] Among them, U is the discharge voltage; U0 is the switching impulse discharge voltage of the positive polarity of the rod-plate at an altitude of 0 m, and its unit is kV; H is the altitude, and its unit is m; k1 is the shape factor, k2 is the altitude factor, k1 and k2 are dimensionless, and e takes 2.7183;

[0164] The intermediate fitting discharge voltage calculation model generation module is used to update the initial fitting discharge voltage calculation model with model parameters to generate an intermediate fitting discharge voltage calculation model.

[0165] The target fitting discharge voltage calculation model generation sub-module is used to update the intermediate fitting discharge voltage calculation model according to the test value of the discharge voltage to generate a target fitting discharge voltage calculation model.

[0166] Optionally, the target fitting discharge voltage calculation model generation sub-module can perform the following steps:

[0167] Substitute the intermediate altitudes corresponding to each preset altitude into the intermediate fitting discharge voltage calculation model for discharge voltage calculation to generate discharge voltage calculation values;

[0168] Substitute the discharge voltage calculation values and the test values of the discharge voltage into a preset error calculation formula for error calculation to generate a relative root mean square error;

[0169] The preset error calculation formula is:

[0170]

[0171] In the formula, δ is the relative root mean square error; n represents the total number of intermediate altitudes; i takes values of 1, 2... n; U i is the test value of the discharge voltage at the i-th intermediate altitude; U′ i is the calculated value of the discharge voltage at the i-th intermediate altitude;

[0172] Update the intermediate fitting discharge voltage calculation model according to the relative root mean square error and the preset error threshold to generate a target fitting discharge voltage calculation model.

[0173] Optionally, the target fitting discharge voltage calculation model generation sub-module can also perform the following steps:

[0174] Judge whether the relative root mean square error is greater than the preset error threshold;

[0175] If so, take the average value of the discharge voltage calculation value and the discharge voltage test value as the corresponding switching impulse discharge voltage;

[0176] Substitute the switching impulse discharge voltage into the discharge voltage calculation model of the intermediate fitting to correct the model parameters, and generate the discharge voltage calculation model of the target fitting;

[0177] If not, then use the discharge voltage calculation model of the intermediate fitting as the discharge voltage calculation model of the target fitting.

[0178] An embodiment of the present invention also provides an electronic device, which 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 executes the discharge voltage calculation method of the end fitting in any of the above embodiments.

[0179] The memory may 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 program codes for executing any method steps in the above methods. For example, the storage space for program codes may include respective program codes for implementing various steps in the above methods. These program codes may be read out from or written into one or more computer program products. These computer program products include program code carriers such as hard disks, compact discs (CDs), memory cards, or floppy disks. The program codes may be compressed in a suitable form. When these codes are run by a computing processing device, the computing processing device is caused to execute each step in the discharge voltage calculation method of the end fitting described above.

[0180] An embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the discharge voltage calculation method of the end fitting in any of the above embodiments.

[0181] 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 foregoing method embodiments, and will not be elaborated herein.

[0182] In 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 illustrative. For example, the division of units is only a logical function division, and 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, the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of devices or units can be in electrical, mechanical, or other forms.

[0183] 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 over multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0184] In addition, each functional unit in various embodiments of the present invention may be integrated in a processing unit, may exist separately as individual physical units, or two or more units may be integrated in one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

[0185] 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 such an 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. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0186] The above embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of various embodiments of the present invention.

Claims

1. A method for calculating the discharge voltage of end fittings, characterized in that, Including: Obtain the structural data of the end fitting and the actual altitude, and use the finite element method to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances, and generate electric field distribution data; Conduct a positive polarity switching impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the positive polarity switching impulse discharge voltage of the fitting; Conduct a positive polarity switching impulse test on the intermediate altitude corresponding to each of the preset altitudes according to the streamer critical inception voltage to generate a discharge voltage test value; Update the initial fitting discharge voltage calculation model according to the positive polarity switching impulse discharge voltage of the fitting and the discharge voltage test value to generate a target fitting discharge voltage calculation model, including: select the discharge voltage corresponding to the gap distance of the positive polarity switching impulse discharge voltage of the fitting from the preset rod-plate positive polarity switching impulse discharge voltage database to generate a gap distance discharge voltage; Substitute the gap distance discharge voltage and the positive polarity switching impulse discharge voltage of the fitting into the initial fitting discharge voltage calculation model to calculate the model parameters and generate model parameters; the initial fitting discharge voltage calculation model is: Where U is the discharge voltage; U0 is the rod-plate positive polarity switching impulse discharge voltage at an altitude of 0m, and its unit is kV; H is the altitude, and its unit is m; k1 is the shape factor, k2 is the altitude factor, k1 and k2 are dimensionless, and e takes 2.7183; Update the initial fitting discharge voltage calculation model with the model parameters to generate an intermediate fitting discharge voltage calculation model; Update the intermediate fitting discharge voltage calculation model according to the discharge voltage test value to generate a target fitting discharge voltage calculation model; Substitute the actual altitude into the target fitting discharge voltage calculation model for voltage calculation to generate the discharge voltage corresponding to the end fitting.

2. The method for calculating the discharge voltage of end fittings according to claim 1, characterized in that, The step of conducting a positive polarity switching impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the positive polarity switching impulse discharge voltage of the fitting includes: Substitute the electric field distribution data into the preset photoionization model to calculate the streamer critical inception voltage value of the discharge of the end fitting and generate the streamer critical inception voltage; The photoionization criterion corresponding to the preset photoionization model is: where r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionospheric boundary, determined by α = η; α is the ionization coefficient; η is the adsorption coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor; Start pressurizing from the streamer critical inception voltage to conduct a positive polarity switching impulse discharge test on the test device corresponding to the end fitting to generate the positive polarity switching impulse discharge voltage of the fitting.

3. The method for calculating the discharge voltage of end fittings according to claim 2, characterized in that, The step of updating the intermediate fitting discharge voltage calculation model according to the discharge voltage test value to generate a target fitting discharge voltage calculation model includes: Substitute the intermediate altitude corresponding to each of the preset altitudes into the intermediate fitting discharge voltage calculation model for discharge voltage calculation to generate a discharge voltage calculation value; Substitute the discharge voltage calculation value and the discharge voltage test value into a preset error calculation formula for error calculation to generate a relative root mean square error; The preset error calculation formula is: Where δ is the relative root mean square error; n represents the total number of intermediate altitude levels; i takes values of 1, 2... n; U i is the test value of the discharge voltage at the i-th intermediate altitude level; U i ' is the calculated value of the discharge voltage at the i-th intermediate altitude level; Update the intermediate fitting discharge voltage calculation model according to the relative root mean square error and the preset error threshold to generate a target fitting discharge voltage calculation model.

4. The method for calculating the discharge voltage of end fittings according to claim 3, characterized in that, The step of updating the intermediate fitting discharge voltage calculation model according to the relative root mean square error and the preset error threshold to generate a target fitting discharge voltage calculation model includes: Determine whether the relative root mean square error is greater than the preset error threshold; If so, use the average value of the calculated discharge voltage value and the test discharge voltage value as the corresponding switching impulse discharge voltage; Substitute the switching impulse discharge voltage into the intermediate fitting discharge voltage calculation model to correct the model parameters and generate a target fitting discharge voltage calculation model; If not, use the intermediate fitting discharge voltage calculation model as the target fitting discharge voltage calculation model.

5. A system for calculating the discharge voltage of end fittings, characterized in that, including: An electric field distribution data generation module, configured to obtain the structural data of the end fitting and the actual altitude, and use the finite element method to calculate the electric field distribution of the structural data at multiple preset altitudes and multiple preset gap distances to generate electric field distribution data; A streamer critical inception voltage and fitting positive switching impulse discharge voltage determination module, configured to perform a positive switching impulse discharge test according to the electric field distribution data to determine the streamer critical inception voltage and the fitting positive switching impulse discharge voltage; A discharge voltage test value generation module, configured to perform a positive switching impulse test on the intermediate altitude corresponding to each preset altitude according to the streamer critical inception voltage to generate a discharge voltage test value; A target fitting discharge voltage calculation model generation module, configured to update the initial fitting discharge voltage calculation model according to the fitting positive switching impulse discharge voltage and the discharge voltage test value to generate a target fitting discharge voltage calculation model, including: selecting the discharge voltage corresponding to the gap distance of the fitting positive switching impulse discharge voltage from a preset rod-plate positive switching impulse discharge voltage database to generate a gap distance discharge voltage; Substitute the gap distance discharge voltage and the fitting positive switching impulse discharge voltage into the initial fitting discharge voltage calculation model to calculate the model parameters. The initial fitting discharge voltage calculation model is: where U is the discharge voltage; U0 is the rod-plate positive switching impulse discharge voltage at an altitude of 0m, with the unit of kV; H is the altitude, with the unit of m; k1 is the shape factor, k2 is the altitude factor, k1 and k2 are dimensionless, and e takes 2.7183; Use the model parameters to update the initial fitting discharge voltage calculation model to generate an intermediate fitting discharge voltage calculation model; Update the intermediate fitting discharge voltage calculation model according to the discharge voltage test value to generate a target fitting discharge voltage calculation model; A discharge voltage generation module, configured to substitute the actual altitude into the target fitting discharge voltage calculation model to calculate the voltage and generate the discharge voltage corresponding to the end fitting.

6. The end fitting discharge voltage calculation system according to claim 5, wherein, The streamer critical inception voltage and fitting positive switching impulse discharge voltage determination module includes: A streamer critical initial voltage generation module, configured to substitute the electric field distribution data into a preset photoionization model to calculate the streamer critical initial voltage value of the end fitting, and generate a streamer critical initial voltage; The photoionization criterion corresponding to the preset photoionization model is: where r is the electrode radius; r1 is the radius of the head of the electron avalanche; z i represents the ionospheric boundary, determined by α = η; α is the ionization coefficient; η is the adsorption coefficient; γ ph is the surface photoelectron emission coefficient; μ is the photon absorption coefficient; g(l) is the geometric factor; A positive-polarity switching impulse discharge voltage generation module for the end fitting, configured to perform a positive-polarity switching impulse discharge test on the test device corresponding to the end fitting starting from the streamer critical initial voltage, and generate a positive-polarity switching impulse discharge voltage for the end fitting.

7. An electronic device, wherein, It includes a memory and a processor. 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 discharge voltage of the end fitting according to any one of claims 1 to 4.

8. A computer-readable storage medium having a computer program stored thereon, wherein, When the computer program is executed, it implements the method for calculating the discharge voltage of the end fitting according to any one of claims 1 to 4.

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