Preformed spacer corona discharge degree estimation method and system

Abstract

The invention relates to a pre-twisted spacer corona discharge degree estimation method and system. The method comprises the following steps: acquiring parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires and the diameter of a split conductor; obtaining the ratio of the average maximum electric field intensity of the surface of the pre-twisted spacer to the average maximum electric field intensity of the surface of the split conductor; obtaining the average maximum electric field intensity on the surface of the split conductor; obtaining the average maximum electric field intensity of the surface of the pre-twisted spacer; calculating the ratio of the average maximum electric field intensity to the corona onset electric field intensity on the surface of the pre-twisted spacer to obtain the corona discharge degree of the pre-twisted spacer; according to the estimation formula of the average maximum field intensity on the surface of the pre-twisted spacer, the field intensity on the surface of the pre-twisted spacer can be reduced by means of increasing the number and diameter of the pre-twisted wires and the like, so that the corona discharge level is reduced, and the electromagnetic environment problem caused by the corona discharge level is controlled.

Description

Technical Field

[0001] The invention relates to the technical field of high voltage power transmission, and in particular to a method and system for estimating the degree of corona discharge of a pre-twisted spacer rod. Background Art

[0002] At present, China's UHV transmission network has built and put into operation "20 direct and 18 cross" lines. The total length of UHV transmission lines in operation has exceeded 50,000 kilometers. UHV transmission lines have the characteristics of a wide distribution range, great differences in natural environment in different regions, and great differences in bearing characteristics in different regions. They need to face challenges such as large spans, large height differences, icing, and breeze vibration, which puts higher requirements on the electrical performance, mechanical performance and stability of power fittings in all aspects.

[0003] Spacers are used for split conductors of transmission lines of all voltage levels. The main purpose of spacers is to limit the relative movement between sub-conductors and maintain the geometric shape of the split conductors under normal circumstances. The mechanical strength of the spacers should be able to withstand the unbalanced tension of the conductors, sub-span oscillations, and the pulling and pressure between the sub-conductors applied by people on a single conductor. The spacers should have a firm grip on the conductors during normal operation or when the conductors are twisted.

[0004] According to the fixing method of the spacer bar and the conductor, the spacer bar can be divided into conventional spacer bars and pre-twisted spacer bars. Conventional spacer bars use the wire clamp cover on the wire clamp to clamp the conductor to fix the spacer bar to the conductor, while pre-twisted spacer bars use pre-twisted wire to wrap the wire clamp around the conductor to fix the spacer bar wire clamp to the conductor. Conventional spacer bars only contact the conductor at the wire clamp cover, and the contact area is small, so the static pressure of the contact surface is relatively large. Pre-twisted spacer bars use pre-twisted wire to fix the spacer bar, and the contact area between the pre-twisted wire and the conductor is larger, which can effectively disperse the internal static pressure of the hardware to a sufficiently large range, thereby effectively increasing the grip and avoiding wire breakage. They are mostly used in large spans, large height differences, high altitudes, and deserted areas.

[0005] The degree of corona discharge of the spacer bar is related to the electric field strength on its surface. The maximum electric field strength on the surface of a conventional spacer bar is located at the head of the wire clamp; the maximum electric field strength on the surface of a pretwisted spacer bar is located on the pretwisted wire, and the curvature radius of the pretwisted wire is smaller than that of the head of the wire clamp. Therefore, the maximum electric field strength on the surface of the pretwisted spacer bar is greater than that of the conventional spacer bar, and corona discharge is more likely to occur than conventional spacer bars, resulting in complex modeling and large amount of calculation when calculating the surface electric field of the pretwisted spacer bar, and the electromagnetic environment problems brought about are more prominent. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a method and system for estimating the degree of corona discharge of a pre-twisted spacer rod, which has the advantage of being able to solve the problems of complex modeling and large amount of calculation when calculating the surface electric field of the pre-twisted spacer rod; at the same time, the electromagnetic environment problems caused are controlled.

[0007] The above-mentioned object of the present invention is achieved through the following technical solutions: On the one hand, the present invention provides a method for estimating the degree of corona discharge of a pre-twisted spacer rod, comprising the following steps:

[0008] Obtain the parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split wires;

[0009] According to the connection mode between the pre-twisted spacer and the split conductor, the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the average maximum electric field intensity on the surface of the split conductor is calculated;

[0010] Calculating and obtaining the average maximum electric field strength on the surface of the split conductor;

[0011] Calculating and obtaining the average maximum electric field strength on the surface of the pre-twisted spacer rod;

[0012] The ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity is calculated, and the ratio indicates the extent of the corona discharge of the pre-twisted spacer.

[0013] Preferably, in the method for estimating the degree of corona discharge of the pre-twisted spacer provided by the present invention, the calculation formula for the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor is:

[0014]

[0015] Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

[0016] Preferably, in the method for estimating the degree of corona discharge of pre-twisted spacer bars provided by the present invention, for hook-type pre-twisted spacer bars, the value range of K1 is 0.9439-1.0419, the value range of K2 is 0.4382-0.4653, and the value range of K3 is 0.2796-0.3467.

[0017] Preferably, in the method for estimating the degree of corona discharge of pre-twisted spacer bars provided by the present invention, for forked pre-twisted spacer bars, the value range of K1 is 0.6816-0.7108, the value range of K2 is 0.8832-1.0418, and the value range of K3 is 0.4484-0.4913.

[0018] Preferably, in the method for estimating the degree of corona discharge of the pre-twisted spacer provided by the present invention, the calculation formula for the average maximum electric field intensity on the surface of the pre-twisted spacer is:

[0019] E=WE0

[0020] Wherein, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

[0021] Preferably, in the method for estimating the degree of corona discharge of pre-twisted spacer rods provided by the present invention, the surface electric field of the split conductor is calculated by using finite element method, simulated charge method or approximate formula method.

[0022] Preferably, in the method for estimating the degree of corona discharge of the pre-twisted spacer provided by the present invention, the calculation formula for the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity is:

[0023]

[0024] Wherein, Q is the average maximum electric field intensity and corona initiation electric field intensity on the surface of pre-twisted spacer; E is the average maximum electric field intensity on the surface of pre-twisted spacer, in kV / cm; E c -Corona initiation field strength on the surface of the split conductor, in kV / cm.

[0025] In another aspect, the present invention provides a system for estimating the degree of corona discharge of a pre-twisted spacer rod, comprising:

[0026] A parameter acquisition unit is configured to acquire parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split wires;

[0027] A ratio calculation unit is configured to calculate the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor according to the connection mode between the pre-twisted spacer and the split conductor;

[0028] The split conductor surface field strength calculation unit is configured to calculate and obtain the average maximum electric field strength on the surface of the split conductor;

[0029] A pre-twisted spacer surface electric field calculation unit is configured to calculate and obtain an average maximum electric field intensity on the surface of the pre-twisted spacer;

[0030] The discharge degree estimation unit is configured to calculate the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity, and the ratio indicates the magnitude of the corona discharge degree of the pre-twisted spacer.

[0031] Preferably, in the pre-twisted spacer corona discharge degree estimation system provided by the present invention, in the ratio calculation unit, the ratio calculation formula of the average maximum electric field intensity on the surface of the pre-twisted spacer to the average maximum electric field intensity on the surface of the split conductor is:

[0032]

[0033] Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

[0034] Preferably, in the pre-twisted spacer corona discharge degree estimation system provided by the present invention, in the pre-twisted spacer surface electric field calculation unit, the calculation formula for the average maximum electric field intensity on the surface of the pre-twisted spacer is:

[0035] E=WE0

[0036] Wherein, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

[0037] In summary, the beneficial technical effects of the present invention are as follows: the method and system for estimating the degree of corona discharge of a pre-twisted spacer provided in the present application, the method comprising the following steps: obtaining the parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires and the diameter of the split conductors; calculating the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductors according to the connection method between the pre-twisted spacer and the split conductors; calculating the average maximum electric field strength on the surface of the split conductors; calculating the average maximum electric field strength on the surface of the pre-twisted spacer; calculating the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the corona initiation electric field strength, and the ratio indicates the degree of corona discharge of the pre-twisted spacer. The system comprises a parameter acquisition unit, a ratio calculation unit, a split conductor surface field strength calculation unit, a pre-twisted spacer surface electric field calculation unit and a discharge degree estimation unit; the surface field strength of the pre-twisted spacer is calculated indirectly, and the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the corona initiation electric field strength is calculated to obtain the corona discharge degree of the pre-twisted spacer; according to the estimation formula of the average maximum field strength on the surface of the pre-twisted spacer, the surface field strength of the pre-twisted spacer can be reduced by increasing the number and diameter of the pre-twisted wires, thereby reducing the corona discharge level and controlling the electromagnetic environment problems caused thereby. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a flowchart of a method for estimating the degree of corona discharge of a pre-twisted spacer rod provided in an embodiment of the present invention.

[0039] Figure 2 It is a schematic structural diagram of a hook-type pre-twisted spacer rod provided in an embodiment of the present invention.

[0040] Figure 3 It is a schematic structural diagram of a fork-type pre-twisted spacer rod provided in an embodiment of the present invention.

[0041] Figure 4 It is a schematic diagram of the winding method of the pre-twisted wire and the split conductor in the hook-type pre-twisted spacer provided in an embodiment of the present invention.

[0042] Figure 5 It is a schematic diagram of the winding method of the pre-twisted wires and the split conductors in the fork-type pre-twisted spacer provided in an embodiment of the present invention.

[0043] Figure 6 This is the surface electric field cloud diagram of a conventional spacer rod.

[0044] Figure 7 It is a cloud diagram of the surface electric field of the pre-twisted wire in the hook-type pre-twisted spacer provided in an embodiment of the present invention.

[0045] Figure 8 It is a surface electric field cloud diagram of the pre-twisted wire in the fork-type pre-twisted spacer provided in an embodiment of the present invention.

[0046] Fig. 9 It is a structural block diagram of a system for estimating the degree of corona discharge of pre-twisted spacer rods provided in another embodiment of the present invention.

[0047] In the figure, 1. split conductor; 2. pre-twisted wire; 3. pre-twisted spacer rod corona discharge degree estimation system; 31. parameter acquisition unit; 32. ratio calculation unit; 33. split conductor surface field strength calculation unit; 34. pre-twisted spacer rod surface electric field calculation unit; 35. discharge degree estimation unit. DETAILED DESCRIPTION

[0048] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0049] Reference Figure 1 , is a method for estimating the degree of corona discharge of a pre-twisted spacer disclosed in the present invention, which calculates the average maximum electric field intensity on the surface of the pre-twisted spacer in an indirect manner according to the design parameters of the pre-twisted spacer and the split conductor 1 and the obtained voltage of the split conductor 1, wherein the method for estimating the degree of corona discharge of the pre-twisted spacer comprises the following steps:

[0050] S101, obtaining parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split conductors.

[0051] Reference Figures 2 to 5In order to avoid excessive field strength at the end of the pre-twisted wire 2, when installing the pre-twisted wire 2, the end of the pre-twisted wire should be polished into a duckbill shape or a hemispherical shape and placed inside the polygon formed by the split conductor 1.

[0052] The electric field on the surface of the pre-twisted spacer was calculated. The results showed that the maximum field strength on the surface of the pre-twisted spacer was located on the pre-twisted wire 2, and the number of pre-twisted wires, the diameter of the pre-twisted wires and the diameter of the split conductors jointly affected the ratio of the average maximum electric field strength on the surface of the pre-twisted wires to the average maximum electric field strength on the surface of the split conductors. Therefore, the parameters obtained were the number of pre-twisted wires n, the diameter of the pre-twisted wires d, and the diameter of the split conductors D. Figure 6 This is the surface electric field cloud diagram of the conventional spacer rod. Figure 7 The surface electric field cloud diagram of the pre-twisted wire in the hook-type pre-twisted spacer provided by the present invention, Figure 8 The electric field cloud diagram of the surface of the pre-twisted wire in the fork-type pre-twisted spacer provided by the present invention shows that the maximum electric field intensity on the surface of the pre-twisted spacer is greater than that on the surface of the conventional spacer, and the discharge area is larger, so the electromagnetic environment problems brought about are more prominent.

[0053] S102. According to the connection mode between the pre-twisted spacer and the split conductor 1, a ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor is calculated.

[0054] Among them, the calculation formula for the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the average maximum electric field strength on the surface of the split conductor is:

[0055]

[0056] Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

[0057] Since the winding methods of the pre-twisted wire 2 of the hook-type pre-twisted spacer and the fork-type pre-twisted spacer are different, the values ​​of K1, K2, and K3 are also different. For the hook-type pre-twisted spacer, the value range of K1 is 0.9439~1.0419, the value range of K2 is 0.4382~0.4653, and the value range of K3 is 0.2796~0.3467; for the fork-type pre-twisted spacer, the value range of K1 is 0.6816~0.7108, the value range of K2 is O.8832~1.0418, and the value range of K3 is 0.4484~0.4913.

[0058] S103. Calculate and obtain the average maximum electric field strength on the surface of the split conductor.

[0059] Among them, the amount of calculation of the surface electric field of the split conductor 1 is relatively much smaller, and the calculation of the average maximum field strength of the split conductor 1 has a mature theoretical support. The calculation of the surface electric field of the split conductor can be calculated using the finite element method, the simulated charge method or the approximate formula method.

[0060] S104, calculating and obtaining the average maximum electric field intensity on the surface of the pre-twisted spacer rods.

[0061] Among them, the calculation formula for the average maximum electric field strength on the surface of the pre-twisted spacer is:

[0062] E=WE0

[0063] Among them, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

[0064] Specifically, in order to verify the effectiveness and accuracy of the above-mentioned calculation method of the average maximum electric field strength on the surface of the pre-twisted spacer, a comparative verification was carried out using different parameters of four-, six-, and eight-split pre-twisted spacers used in my country's ±660kV, ±800kV, and ±1100kV DC transmission projects.

[0065] Among them, under different voltage levels and split numbers, multiple examples with different line parameters and spacer bar structural parameters were randomly selected for comparative verification and formula calculation and simulation calculation. The splitting spacing of the split conductor 1 used in this embodiment is fixed at 450mm, and the value range of the conductor diameter D is 34-58mm; the pre-twisted wire diameter of the hook-type pre-twisted spacer is 3.6-6mm, and the number of twisted wires is 2-6; the pre-twisted wire diameter of the fork-type pre-twisted spacer is 7.6-11.6mm, and the number of pre-twisted wires is 2, 4, 6, and 8.

[0066] The calculation results are shown in Tables 1, 2, 3, 4, 5, and 6.

[0067] Table 1 Surface field strength analysis and verification of hook-type four-split pre-twisted spacer

[0068]

[0069] Table 2 Surface field strength analysis and verification of hook-type six-split pre-twisted spacer rods

[0070]

[0071] Table 3 Surface field strength analysis and verification of hook-type eight-split pre-twisted spacer rods

[0072]

[0073]

[0074] Table 4 Surface field strength analysis and verification of forked four-split pre-twisted spacer rods

[0075]

[0076] Table 5 Surface field strength analysis and verification of forked six-split pre-twisted spacer rods

[0077]

[0078] Table 6 Surface field strength analysis and verification of forked eight-split pre-twisted spacer rods

[0079]

[0080] This embodiment provides a reference for the preset value of the hook-type pre-twisted spacer: K1 = 0.9934,

[0081] K2=0.4518, K3=0.3018; fork type pre-twisted spacer preset value reference: K1=0.7024, K2=0.9376, K3=0.4698. From the above calculation results, it can be seen that the relative error of the formula calculation value proposed by the present invention is controlled within ±1% compared with the finite element simulation value.

[0082] By proposing an estimation formula for the average maximum electric field strength on the surface of pre-twisted spacer rods, the maximum error of the prediction does not exceed ±1%.

[0083] The average maximum field strength on the surface of the pre-twisted spacer is 1.7-1.9 times that of the split conductor, so the corona discharge at the pre-twisted wire 2 is stronger. According to the estimation formula of the average maximum field strength on the surface of the pre-twisted spacer, the surface field strength of the pre-twisted spacer can be reduced by increasing the number and diameter of the pre-twisted wires, thereby reducing the corona discharge level and controlling the electromagnetic environment problems caused by it, providing a technical reference for the corona prevention and control of pre-twisted spacers.

[0084] S105, calculating the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity, the ratio indicating the extent of the corona discharge of the pre-twisted spacer.

[0085] Specifically, the corona initiation electric field strength of the conductor is calculated with reference to the peek formula, and the average maximum electric field strength on the surface of the pre-twisted spacer obtained by S104 is ratioed to the corona initiation electric field strength.

[0086] Among them, the calculation formula for the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer rod to the corona initiation electric field intensity is:

[0087]

[0088] Wherein, Q is the average maximum electric field intensity and corona initiation electric field intensity on the surface of pre-twisted spacer; E is the average maximum electric field intensity on the surface of pre-twisted spacer, in kV / cm; E c -Corona initiation field strength on the surface of the split conductor, in kV / cm.

[0089] Specifically, a ratio Q less than 1 indicates no discharge, and a ratio Q greater than 1 indicates that corona discharge will occur in the pre-twisted spacer, and the larger the ratio, the more severe the discharge.

[0090] Continue to refer to Fig. 9 Another embodiment provides a system 3 for estimating the degree of corona discharge of a pre-twisted spacer, comprising: a parameter acquisition unit 31, configured to acquire parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split conductor; a ratio calculation unit 32, configured to calculate the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor according to the connection mode between the pre-twisted spacer and the split conductor 1; a split conductor surface field strength calculation unit 33, configured to calculate the average maximum electric field strength on the surface of the split conductor; a pre-twisted spacer surface electric field calculation unit 34, configured to calculate the average maximum electric field strength on the surface of the pre-twisted spacer;

[0091] The discharge degree estimation unit 35 is configured to calculate the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity, and the ratio indicates the extent of the corona discharge of the pre-twisted spacer.

[0092] The specific processing of the parameter acquisition unit 31, the ratio calculation unit 32, the split wire surface field strength calculation unit 33, the pre-twisted spacer surface electric field calculation unit 34 and the discharge degree estimation unit 35 of the pre-twisted spacer corona discharge degree estimation system 3 in this embodiment can be referred to Figure 1 Corresponding to S101, S102, S103, S104 and S105 in the embodiment.

[0093] Among them, in the ratio calculation unit 32, the calculation formula for the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the average maximum electric field strength on the surface of the split conductor is:

[0094]

[0095] Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

[0096] Furthermore, in this embodiment, in the pre-twisted spacer surface electric field calculation unit 34, the calculation formula for the average maximum electric field intensity on the surface of the pre-twisted spacer is:

[0097] E=WE0

[0098] Wherein, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

[0099] Among them, in the discharge degree estimation unit 35, the calculation formula for the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer rod to the corona initiation electric field intensity is:

[0100]

[0101] Wherein, Q is the average maximum electric field intensity and corona initiation electric field intensity on the surface of pre-twisted spacer; E is the average maximum electric field intensity on the surface of pre-twisted spacer, in kV / cm; E c -Corona initiation field strength on the surface of the split conductor, in kV / cm.

[0102] In the discharge degree estimation unit 35, a ratio Q less than 1 indicates no discharge, and a ratio Q greater than 1 indicates that corona discharge occurs in the spacer bar, and the larger the ratio, the more severe the discharge.

[0103] The present application provides a method and system for estimating the degree of corona discharge of a pre-twisted spacer rod, the method comprising the following steps: obtaining the parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires and the diameter of the split conductor; calculating the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the average maximum electric field strength on the surface of the split conductor according to the connection mode of the pre-twisted spacer rod and the split conductor 1; calculating the average maximum electric field strength on the surface of the split conductor; calculating the average maximum electric field strength on the surface of the pre-twisted spacer rod; calculating the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the corona initiation electric field strength, the ratio indicating the degree of corona discharge of the pre-twisted spacer rod; the system The system includes a parameter acquisition unit 31, a ratio calculation unit 32, a split conductor surface field strength calculation unit 33, a pre-twisted spacer surface electric field calculation unit 34 and a discharge degree estimation unit 35; the surface field strength of the pre-twisted spacer is calculated indirectly, and the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the corona initiation electric field strength is calculated to obtain the corona discharge degree of the pre-twisted spacer; according to the estimation formula of the average maximum field strength on the surface of the pre-twisted spacer, the surface field strength of the pre-twisted spacer can be reduced by increasing the number and diameter of the pre-twisted wires, thereby reducing the corona discharge level and controlling the electromagnetic environment problems caused thereby.

[0104] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0105] Finally, it should be noted that: Obviously, the above embodiments are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from this are still within the scope of protection of the present invention.

Claims

1. A method for estimating the degree of corona discharge of a pre-twisted spacer, characterized in that: The steps include: Obtain the parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split wires; According to the connection mode between the pre-twisted spacer and the split conductor, the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the average maximum electric field intensity on the surface of the split conductor is calculated; Calculating and obtaining the average maximum electric field strength on the surface of the split conductor; Calculating and obtaining the average maximum electric field strength on the surface of the pre-twisted spacer rod; The ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity is calculated, and the ratio indicates the extent of the corona discharge of the pre-twisted spacer.

2. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 1, characterized in that: The calculation formula for the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the average maximum electric field strength on the surface of the split conductor is: Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

3. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 2, characterized in that: For hook-type pre-twisted spacers, the value range of K1 is 0.9439~1.0419, the value range of K2 is 0.4382~0.4653, and the value range of K3 is 0.2796~0.3467.

4. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 2, characterized in that: For the fork-type pre-twisted spacer rod, the value range of K1 is 0.6816~0.7108, the value range of K2 is 0.8832~1.0418, and the value range of K3 is 0.4484~0.4913.

5. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 1, characterized in that: The calculation formula for the average maximum electric field strength on the surface of the pre-twisted spacer rod is: E=WE0 Wherein, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

6. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 1, characterized in that: The split conductor surface electric field calculation is performed using a finite element method, a simulated charge method or an approximate formula method.

7. The method for estimating the degree of corona discharge of a pre-twisted spacer rod according to claim 1, characterized in that: The calculation formula for the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer rod to the corona initiation electric field intensity is: Wherein, Q is the average maximum electric field intensity and corona initiation electric field intensity on the surface of pre-twisted spacer rods; E is the average maximum electric field intensity on the surface of pre-twisted spacer rods, in kV / cm; E c -Corona initiation field strength on the surface of the split conductor, in kV / cm.

8. A pre-twisted spacer rod corona discharge degree estimation system, characterized in that: include: A parameter acquisition unit is configured to acquire parameters of the number of pre-twisted wires, the diameter of the pre-twisted wires, and the diameter of the split wires; A ratio calculation unit is configured to calculate the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor according to the connection mode between the pre-twisted spacer and the split conductor; The split conductor surface field strength calculation unit is configured to calculate and obtain the average maximum electric field strength on the surface of the split conductor; A pre-twisted spacer surface electric field calculation unit is configured to calculate and obtain an average maximum electric field intensity on the surface of the pre-twisted spacer; The discharge degree estimation unit is configured to calculate the ratio of the average maximum electric field intensity on the surface of the pre-twisted spacer to the corona initiation electric field intensity, and the ratio indicates the magnitude of the corona discharge degree of the pre-twisted spacer.

9. The pre-twisted spacer rod corona discharge degree estimation system according to claim 8, characterized in that: In the ratio calculation unit, the calculation formula for the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer rod to the average maximum electric field strength on the surface of the split conductor is: Wherein, n is the number of pre-twisted wires; d is the diameter of the pre-twisted wire; D is the diameter of the split conductor; K1, K2, and K3 are preset constants.

10. The pre-twisted spacer rod corona discharge degree estimation system according to claim 1, characterized in that: In the pre-twisted spacer surface electric field calculation unit, the calculation formula for the average maximum electric field intensity on the pre-twisted spacer surface is: E=WE0 Wherein, E0 is the average maximum electric field strength on the surface of the split conductor, in kV / cm; E is the average maximum electric field strength on the surface of the pre-twisted spacer, in kV / cm; W is the ratio of the average maximum electric field strength on the surface of the pre-twisted spacer to the average maximum electric field strength on the surface of the split conductor.

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