Power cable withstand voltage test method and device based on withstand voltage equivalent analysis, and terminal

[0065] In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are set forth in order to provide a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0066] In order to make the objectives, technical solutions and advantages of the present invention clearer, the following descriptions will be given through specific embodiments in conjunction with the accompanying drawings.

[0067] Most of the breakdown accidents of Crosslinked Polyethylene Cable (XLPE) cables are closely related to the main insulation of the power cable system. The withstand voltage test is the basic test for evaluating the insulation performance of the cable. It is a handover test that must be carried out before the power cable is put into operation. It can find out the larger defects inside the power cable.

[0068] The pin plate electrode defect is a typical defect in power cables, and it is also one of the main reasons for cable insulation breakdown. Defects in the needle plate electrode will form an extremely uneven electric field inside the power cable, which will seriously reduce the breakdown voltage of the power cable.

[0069] The power cable insulation withstand voltage test is the basic test to evaluate the insulation performance of the power cable, and it is a handover test that must be carried out before the power cable is put into operation. The voltage type of withstand voltage assessment mainly includes AC withstand voltage, DC withstand voltage and 0.1Hz ultra-low frequency withstand voltage. However, due to differences in test voltages, test models and statistical methods, the test results are also biased or even inconsistent.

[0070] Based on the above problems, the embodiment of the present invention provides a power cable withstand voltage test method based on the withstand voltage equivalent analysis. According to the analysis results, follow-up power cable tests are carried out.

[0071] Here, firstly, the steps of the acquisition process of the preset equivalent analysis results are introduced, such as figure 1 shown:

[0072] Step S110 , applying a frequency voltage and a 0.1 Hz cosine square wave voltage respectively on a plurality of groups of insulation defect models with different insulation residual thicknesses to perform a withstand voltage test.

[0073] In some embodiments, the plurality of sets of insulation defect models with different insulation residual thicknesses include insulation defect models with insulation residual thicknesses of 0.2 mm, 0.3 mm, 0.4 mm, and 0.5 mm. It is also possible to make other insulation defect models with different insulation residual thicknesses according to the actual power cable testing requirements.

[0074] Optionally, the insulation defect model may be a pin plate electrode defect model. The needle plate electrode defect model is an important model to study extremely uneven electric field discharge, but no specific provisions are given in the relevant standards. Most of the needle electrodes in the traditional needle plate electrode defect model use a long needle directly inserted into the XLPE sample. Due to the hardness of XLPE, the insertion depth and angle are not easy to control, especially the insertion depth, which has a great influence on the distribution of the electric field of the electrode. This leads to the unsatisfactory control of the distance between the needle electrode and the plate electrode, that is, the remaining thickness of the insulation, and the poor consistency of the electric field distribution at the needle tip position, resulting in a large dispersion of test results.

[0075] To this end, the present invention provides a needle plate electrode defect model with high controllable insulation residual thickness, the overall structure is as follows figure 2 shown. Specifically, the needle plate electrode defect model includes:

[0076] The cross-linked polyethylene cable pressing sheet 203 is arranged between the high voltage electrode 202 and the low voltage electrode 201, wherein the high voltage electrode 202 and the low voltage electrode 201 are made of brass. One end of the tungsten needle electrode 205 is inserted into the cross-linked polyethylene cable pressing sheet 203 through the high voltage electrode 202 , and the other end is set on the screw-in dial 204 . Rotate the precession dial 204 to adjust the depth at which the tungsten needle electrode 205 is inserted into the XLPE cable pressing sheet 203 to obtain insulation defect models with different residual insulation thicknesses.

[0077] First, the XLPE cable pressing sheet 203 sample with a thickness of 2 mm and an area of ​​100 mm*100 mm is pressed with the high voltage electrode 202 and the low voltage electrode 201 . The above-mentioned high-voltage electrode 202 and low-voltage electrode 201 are all made of equal-diameter electrodes specified in GB/T 1408.1-2016, with a size of 25mm×25mm and a brass material with an edge chamfer of 3mm. Then, a screw-in type tungsten needle electrode 205 is placed in the high voltage electrode 202. The diameter of the head of the tungsten needle electrode 205 is 1 mm, the radius of curvature is 20 μm, and the tail is a screw with a pitch of 1 mm. Finally, the insertion depth of the tungsten needle electrode 205 is controlled by the precession dial 204 with a scale, and the depth of the tungsten needle electrode 205 is 0.1 mm per rotation of 36°. Because the needle tip is shorter, the pressure is reduced, and its own deformation is very small. The precession structure can effectively control the insertion depth, and the remaining thickness of the insulation is highly controllable. By controlling the insertion depth of the tungsten needle electrode 205, a plurality of groups of models with insulation remaining thicknesses of 0.2 mm, 0.3 mm, 0.4 mm and 0.5 mm can be prepared.

[0078] In some embodiments, first, in order to prevent the XLPE insulation sample from being affected by surface flashover when the dielectric withstand voltage test is performed in the air, the above-mentioned multiple groups of insulation defect models with different insulation residual thicknesses are placed in the test tank. in insulating oil. And the liquid level of the insulating oil in the test tank is higher than the height of the insulation defect model. The top of the test tank is equipped with a pressure relief valve to prevent explosion that may be caused by sudden pressure increase at the moment of breakdown.

[0079] Then, a power frequency voltage with a preset amplitude and a 0.1 Hz cosine square wave voltage with a preset amplitude are respectively applied to the plurality of groups of the insulation defect models with different residual insulation thicknesses. Specifically, for a 10kV power cable, when using 60min for the withstand voltage test assessment, the preset amplitude value of 2U can be used. 0 The power frequency voltage, and the preset amplitude is 2.5U 0 0.1Hz cosine square wave voltage. For this purpose, the 10kV power cable U 0 As the benchmark, the above-mentioned insulation defect models with different insulation residual thicknesses are respectively applied with a frequency voltage of 2U 0 Voltage and 0.1Hz cosine square wave voltage 2.5U 0 Voltage.

[0080] Finally, when the power frequency voltage of the preset amplitude and the 0.1Hz cosine square wave voltage of the preset amplitude are respectively reached, keep the voltage unchanged, and test the withstand voltage time of the insulation defect model of the remaining insulation thickness of the target group. Specifically, when the voltage reaches the preset amplitude, keep the preset voltage amplitude unchanged, start timing, when the test voltage instantly becomes 0 volts, that is, the insulation defect model is broken down, and stop the timing, that is, the corresponding model is in the corresponding Withstand time at preset voltage.

[0081] Step S120 , obtaining the Weibull distribution of the power frequency voltage and the 0.1 Hz cosine square wave voltage of different insulation residual thicknesses according to the multiple groups of breakdown times and breakdown failure probability obtained by the withstand voltage test.

[0082] In some embodiments, the Weibull distribution is the most common for solid state insulation electrical breakdown test data distributions, which has broad applicability and is of great value for the type of extreme value distribution where the weakest point fails. The invention processes the withstand voltage test data with a two-parameter Weibull distribution.

[0083]

[0084] Among them, t is the breakdown time, F(t) is the breakdown failure probability, α is the scale parameter, and β is the shape parameter. α refers to the breakdown time when the failure probability is 0.632, and β is the slope of the above formula, indicating the dispersion of the test data. The larger the β, the smaller the variation range of the breakdown time. The values ​​of α and β were calculated using White's method. like image 3 and Figure 4 are the Weibull distribution diagrams under the power frequency voltage and 0.1Hz cosine square wave voltage, respectively. in, image 3The curve 1 is the Weibull distribution diagram of the sample with power frequency voltage 0.2mm insulation residual thickness, the curve 2 is the Weibull distribution diagram of the power frequency voltage 0.3mm insulation residual thickness sample, and the curve 3 is the power frequency voltage 0.4mm insulation residual thickness. The Weibull distribution diagram of the thickness sample, curve 4 is the Weibull distribution diagram of the remaining thickness of the insulation sample with a power frequency voltage of 0.5 mm. Figure 4 The curve in is the Weibull distribution of the 0.1Hz cosine square wave voltage 0.2mm insulation residual thickness sample.

[0085] It should be noted here that due to the residual thickness of the 0.3mm, 0.4mm and 0.5mm insulation specimens in 2.5U 0 Under the action of voltage, no breakdown occurred under the condition of the longest action time of 3h, so only the breakdown data statistics of 0.2mm insulation residual thickness samples are given.

[0086] Step S130 , analyzing the equivalence of the power frequency voltage and the 0.1 Hz cosine square wave voltage based on the scale parameters, shape parameters and topographic features of the breakdown channel in the Weibull distribution to obtain an equivalent analysis result.

[0087] In some embodiments, based on the above Weibull distribution image 3 and Figure 4 , and Tables 1 and 2 below, it can be seen that for the power frequency voltage, with the increase of the remaining thickness of the insulation, 2U 0 The α-scale parameters and β-shape parameters under the voltage are gradually increased, the breakdown time is gradually increased, and the variation range of the breakdown time is gradually decreased. For 0.1Hz cosine square wave voltage, all defective samples are at 2.5U 0 Under the action of voltage, no breakdown occurred under the condition of the longest action time of 3h, so only the breakdown data statistics of 0.2mm insulation residual thickness samples are given, which means 2.5U 0 For this type of defect, it is impossible to find such defects under the specified withstand voltage time of 60min.

[0088] Among them, the scale parameters and shape parameters of the power frequency breakdown test are shown in Table 1.

[0089] Table I

[0090] Insulation remaining thickness/mm α/min β 0.5 59.48 1.45 0.4 40.24 1.58 0.3 23.23 1.00 0.2 6.07 0.92

[0091] The scale parameters and shape parameters of the 0.1Hz cosine square wave breakdown test are shown in Table 2.

[0092] Table II

[0093] Insulation remaining thickness/mm α/min β 0.2 348.62 1.11

[0094] For an insulation residual thickness of 0.5mm, the breakdown time is approximately equal to 60min. This means 2U 0 For this type of defect, the residual thickness of the defect can be found to be 0.5mm at most. For the defect of 0.2mm insulation residual thickness, the power frequency voltage only needs 6min to complete the breakdown.

[0095] For the remaining thickness of insulation of 0.2mm, the breakdown time is about 345min, which is much longer than the breakdown time of about 6min under the action of power frequency voltage. This means 2.5U 0 For this type of defect, it is impossible to find such defects under the specified withstand voltage time of 60min.

[0096] further, as Figure 5 and Image 6 Front and side views of the topographical features of the breakdown channel shown, where, Figure 5 and Image 6 The picture on the left is the morphological characteristics of the breakdown channel of the power frequency voltage, and the picture on the right is the morphological characteristics of the breakdown channel of the 0.1Hz cosine square wave voltage. By observing the morphological characteristics of the breakdown channel, it can be seen that the diameter of the breakdown channel of the power frequency voltage is larger than the cosine square wave voltage of 0.1Hz, the breakdown channel is relatively smooth, and the low-voltage electrode side of the breakdown channel is obviously thicker, indicating that the breakdown channel The energy injection at the moment of breakdown is relatively sufficient, and the XLPE material is fully vaporized during the breakdown process. On the other hand, the breakdown channel under 0.1Hz cosine square wave voltage is relatively rough, but relatively uniform, indicating that the energy injection during breakdown is obviously small, the gasification process is insufficient, and the cumulative effect is not significant.

[0097] Through the equivalence analysis of the above-mentioned power frequency voltage and the 0.1Hz cosine square wave voltage, it can be concluded that under the condition of the needle plate electrode defect model, the strength of the 0.1Hz cosine square wave voltage on the cable withstand voltage test is significantly lower than that of the power frequency Voltage. Increasing the voltage of the cosine square wave, the frequency of the cosine square wave or increasing the test time will improve the strength of the cable withstand voltage test.

[0098] After obtaining the preset equivalent analysis results, the withstand voltage test can be performed on the target power cable, such as Figure 7 As shown, the steps of the power cable withstand voltage test method based on the withstand voltage equivalent analysis provided by the embodiment of the present invention include:

[0099] Step S710 , using a 0.1 Hz cosine square wave voltage to perform a withstand voltage test on the target power cable to obtain an initial test result.

[0100] In some embodiments, a 0.1Hz cosine square wave voltage is continuously applied to the target power cable, and when the preset voltage value reaches 2.5U 0 , start timing and keep the preset voltage value of 2.5U 0 constant;

[0101] When the test voltage is displayed as 0, that is, the target power cable is broken down, stop the timing, and obtain the initial withstand voltage time.

[0102] Specifically, the test applied voltage was 30.75kV, and a 0.1Hz cosine square wave voltage was continuously applied to the target 10kV power cable with a residual insulation thickness of 0.2mm. When the preset voltage value reached 2.5U 0 When the voltage breakdown time is 348.62 minutes.

[0103] Step S720: Correct the initial test result according to the preset equivalent analysis result, and determine the corrected test result as the final test result of the target power cable.

[0104] In some embodiments, according to the withstand voltage time of the power frequency voltage and the 0.1Hz cosine square wave voltage to the insulation defect model of the same insulation residual thickness, the initial withstand voltage time of the initial test is performed according to a preset ratio Correction, the corrected withstand voltage time is determined as the final test result of the target power cable.

[0105] Specifically, the strength of the cable withstand voltage assessment through the above-mentioned 0.1Hz cosine square wave voltage is significantly lower than that of the power frequency voltage. The breakdown time of a power cable with a residual thickness of 0.2mm of insulation tested with a 0.1Hz cosine square wave voltage was 348.62 minutes, while when the same model was tested with a power frequency voltage, the breakdown time was only 6.07 minutes. In order to obtain accurate test results, the initial withstand voltage time of the 0.1Hz cosine square wave voltage test must be corrected according to the preset ratio. The preset ratio is a number greater than 1 to obtain accurate withstand voltage time. For different specifications of power cables, different test models, and different test voltages, the preset ratio here is not specifically limited, and the user can limit it according to the specific situation to ensure the accuracy of the test.

[0106] In some embodiments, the frequency of the cosine square wave can also be increased, and the strength of the test to withstand voltage of the cable can also be increased.

[0107] Using a 0.5Hz cosine square wave at 2.5U 0 Under the voltage, the same model as above is used to test, and the test results are shown in Table 3. The scale parameters and shape parameters of the 0.5Hz cosine square wave breakdown test are shown in Table 3. It can be seen that increasing the frequency greatly reduces the breakdown time to about 37.1 min, and the shape parameter β also increases to a certain extent.

[0108] Table 3

[0109] Insulation remaining thickness/mm α/min β 0.2 37.10 1.21

[0110] According to the above equivalence analysis results, the original test results are increased according to a preset ratio, and an accurate withstand voltage test time can be obtained.

[0111] It is also possible to increase the voltage, frequency or test time of the cosine square wave to improve the strength of its withstand voltage assessment, thereby improving the accuracy of the test.

[0112] The embodiment of the present invention provides a power cable withstand voltage test method based on withstand voltage equivalent analysis. First, a 0.1Hz cosine square wave voltage is used to perform a withstand voltage test on a target power cable to obtain an initial test result. Then, the initial test result is corrected according to the preset equivalent analysis result, and finally, the corrected test result is determined as the final test result of the target power cable. Among them, the process of obtaining the preset equivalent analysis results includes: first, applying a frequency voltage and a 0.1Hz cosine square wave voltage to a plurality of groups of insulation defect models with different residual insulation thicknesses to carry out a withstand voltage test; then, according to the withstand voltage The multiple groups of breakdown time and breakdown failure probability obtained from the test can obtain the Weibull distribution of the power frequency voltage and 0.1Hz cosine square wave voltage of different insulation residual thicknesses, respectively. Finally, based on the scale parameters, shape parameters and the morphological characteristics of the breakdown channel in the Weibull distribution, the equivalence of the power frequency voltage and the 0.1Hz cosine square wave voltage is analyzed, and the equivalent analysis results are obtained. In this way, firstly, by analyzing the equivalence of power frequency voltage and 0.1Hz cosine square wave voltage, after obtaining the equivalence analysis result, the power cable can be tested on the basis of the equivalence analysis result, so as to To ensure the accuracy of the withstand voltage test results.

[0113] It should be understood that the size of the sequence numbers of the steps in the above embodiments does not mean the sequence of execution, and the execution sequence of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0114] Based on the power cable withstand voltage test method based on the withstand voltage equivalent analysis provided by the above embodiments, correspondingly, the present invention also provides a withstand voltage equivalent test method applied to the power cable withstand voltage test method based on the withstand voltage equivalent analysis. The specific implementation of the analyzed power cable withstand voltage test device. See the examples below.

[0115] like Figure 8 As shown, a power cable withstand voltage test device 800 based on withstand voltage equivalent analysis is provided, and the device includes:

[0116] The initial test module 810 is used to perform a withstand voltage test on the target power cable by using a 0.1Hz cosine square wave voltage to obtain an initial test result;

[0117] A correction module 820, configured to correct the initial test result according to the preset equivalent analysis result, and determine the corrected test result as the final test result of the target power cable;

[0118] Among them, the acquisition process of the preset equivalent analysis results is as follows: applying a frequency voltage and a 0.1Hz cosine square wave voltage to a plurality of groups of insulation defect models with different residual insulation thicknesses to carry out a withstand voltage test; Set breakdown time and breakdown failure probability, and obtain the Weibull distribution of power frequency voltage and 0.1Hz cosine square wave voltage for different insulation residual thicknesses respectively; based on the scale parameters, shape parameters and the topography of the breakdown channel in the Weibull distribution The equivalence of power frequency voltage and 0.1Hz cosine square wave voltage is analyzed, and the equivalent analysis result is obtained.

[0119] In a possible implementation, it also includes:

[0120] The withstand voltage test module 830 is used to respectively apply a frequency voltage and a 0.1Hz cosine square wave voltage on a plurality of groups of insulation defect models with different insulation residual thicknesses to perform a withstand voltage test;

[0121] The generating distribution module 840 is used to obtain the Weibull distribution of the power frequency voltage and the 0.1Hz cosine square wave voltage of different insulation residual thicknesses according to the multiple sets of breakdown time and breakdown failure probability obtained by the withstand voltage test;

[0122]The equivalent analysis module 850 is used to analyze the equivalence of the power frequency voltage and the 0.1Hz cosine square wave voltage based on the scale parameters, shape parameters and the topographic characteristics of the breakdown channel in the Weibull distribution to obtain an equivalent analysis result;

[0123] Withstand voltage test module 830, also used for

[0124] Place multiple groups of insulation defect models with different insulation residual thicknesses in the insulating oil in the test oil tank; wherein, the liquid level of the insulating oil in the test oil tank is higher than the height of the insulation defect models;

[0125] Apply a power frequency voltage with a preset amplitude and a 0.1Hz cosine square wave voltage with a preset amplitude on multiple groups of insulation defect models with different residual insulation thicknesses;

[0126] When the power frequency voltage of the preset amplitude and the 0.1Hz cosine square wave voltage of the preset amplitude are respectively reached, keep the voltage unchanged, and test the withstand voltage time of the insulation defect model of the remaining thickness of the insulation of the target group; The insulation defect model of the remaining thickness is any one of a plurality of groups of insulation defect models of different insulation remaining thicknesses.

[0127] In a possible implementation manner, the initial test module 810 is also used for

[0128] Continuously apply 0.1Hz cosine square wave voltage to the target power cable, when the preset voltage value is reached, start timing and keep the preset voltage value unchanged;

[0129] When the test voltage is displayed as 0, the target power cable is broken down, and the timing is stopped to obtain the initial withstand voltage time.

[0130] In a possible implementation manner, the correction module 820 is further configured to

[0131] According to the power frequency voltage and 0.1Hz cosine square wave voltage to the withstand voltage time of the insulation defect model of the same insulation residual thickness, the initial withstand voltage time of the initial test is corrected according to the preset ratio, and the corrected withstand voltage time is determined as the target Final test results for power cables.

[0132] In a possible implementation manner, the insulation defect model is a needle plate electrode defect model;

[0133] Needle plate electrode defect models include:

[0134] The cross-linked polyethylene cable pressing sheet arranged between the high-voltage electrode and the low-voltage electrode; wherein, the high-voltage electrode and the low-voltage electrode are made of brass;

[0135] Tungsten needle electrode, one end is inserted into the cross-linked polyethylene cable pressing sheet through the high-voltage electrode, and the other end is set on the screw-in dial; The depth in the sheet is obtained, and the insulation defect model of different insulation residual thickness is obtained.

[0136] In a possible implementation manner, the multiple groups of insulation defect models with different residual insulation thicknesses include insulation defect models with residual insulation thicknesses of 0.2 mm, 0.3 mm, 0.4 mm and 0.5 mm.

[0137] In one possible implementation, the Weibull distribution is:

[0138]

[0139] Among them, t is the breakdown time, F(t) is the breakdown failure probability, α is the scale parameter, and β is the shape parameter.

[0140] Figure 9 It is a schematic diagram of a terminal provided by an embodiment of the present invention. like Figure 9 As shown, the terminal 9 of this embodiment includes: a processor 90 , a memory 91 , and a computer program 92 stored in the memory 91 and executable on the processor 90 . When the processor 90 executes the computer program 92, the steps in each of the foregoing embodiments of the power cable withstand voltage test method based on the withstand voltage equivalent analysis are implemented, for example, Figure 7 The shown steps 710 to 720, or, when the processor 90 executes the computer program 92, implements the functions of the modules/units in the foregoing device embodiments, for example, Figure 8 The functions of modules 810 to 820 are shown.

[0141] Exemplarily, the computer program 92 can be divided into one or more modules 9, and the one or more modules 9 are stored in the memory 91 and executed by the processor 90 to complete the present invention . The one or more modules/units may be a series of computer program instruction segments capable of performing specific functions, and the instruction segments are used to describe the execution process of the computer program 92 in the terminal 9 . For example, the computer program 92 may be divided into Figure 8 Modules 810 to 820 are shown.

[0142] The terminal 9 may be a computing device such as a desktop computer, a notebook computer, a palmtop computer, and a cloud server. The terminal 9 may include, but is not limited to, a processor 90 and a memory 91 . Those skilled in the art can understand that, Figure 9 It is only an example of the terminal 9, and does not constitute a limitation on the terminal 9. It may include more or less components than the one shown, or combine some components, or different components. For example, the terminal may also include input and output devices. , network access equipment, bus, etc.

[0143] The so-called processor 90 may be a central processing unit (Central Processing Unit, CPU), and may also be other general-purpose processors, digital signal processors (Digital Signal Processors, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

[0144] The memory 91 may be an internal storage unit of the terminal 9 , such as a hard disk or a memory of the terminal 9 . The memory 91 may also be an external storage device of the terminal 9, such as a plug-in hard disk equipped on the terminal 9, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, Flash card (Flash Card) and so on. Further, the memory 91 may also include both an internal storage unit of the terminal 9 and an external storage device. The memory 91 is used to store the computer program and other programs and data required by the terminal. The memory 91 can also be used to temporarily store data that has been output or will be output.

[0145] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned functions can be allocated to different functional units, Module completion, that is, dividing the internal structure of the device into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment may be integrated in one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit, and the above-mentioned integrated units may adopt hardware. It can also be realized in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing from each other, and are not used to limit the protection scope of the present application. For the specific working processes of the units and modules in the above-mentioned system, reference may be made to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0146] In the foregoing embodiments, the description of each embodiment has its own emphasis. For parts that are not described or described in detail in a certain embodiment, reference may be made to the relevant descriptions of other embodiments.

[0147] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of the present invention.

[0148] In the embodiments provided by the present invention, it should be understood that the disclosed apparatus/terminal and method may be implemented in other manners. For example, the apparatus/terminal embodiments described above are only illustrative. For example, the division of the modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or Components may be combined or may be integrated into another system, or some features may be omitted, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.

[0149] The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.

[0150] 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 alone, or two or more units may be integrated into one unit. The above-mentioned integrated units may be implemented in the form of hardware, or may be implemented in the form of software functional units.

[0151] The integrated modules, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium. Based on this understanding, the present invention can implement all or part of the processes in the methods of the above embodiments, and can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer When the program is executed by the processor, the steps of the above-mentioned embodiments of the power cable withstand voltage test method based on the withstand voltage equivalent analysis can be implemented. Wherein, the computer program includes computer program code, and the computer program code may be in the form of source code, object code, executable file or some intermediate form, and the like. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, removable hard disk, magnetic disk, optical disk, computer memory, Read-Only Memory (ROM), Random Access Memory (Random Access Memory, RAM), electric carrier signal, telecommunication signal, software distribution medium, etc. It should be noted that the content contained in the computer-readable media may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable media Excluded are electrical carrier signals and telecommunication signals.

[0152] The above-mentioned embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; 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: it can still be used for the foregoing implementations. The technical solutions described in the examples are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the within the protection scope of the present invention.