Method for determining the proportion coefficient of rayleigh damping of icing unit in iced transmission line

Abstract

This application provides a method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing transmission line. After determining the first transmission line parameters and first damping ratio before icing, and the second transmission line parameters and second damping ratio after icing, the method can determine the first mode frequency of the target transmission line under the first mode shape before icing based on the first transmission line parameters, and determine the second mode frequency of the target transmission line under the second mode shape after icing based on the second transmission line parameters. Thus, the Rayleigh damping algorithm can be used to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing. Finally, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated, thereby enabling accurate calculation of the dynamic response of the line under icing and partial icing conditions.

Description

Technical Field

[0001] This application relates to the field of dynamic numerical simulation calculation technology for icing vibration of transmission lines, and in particular to a method for determining the Rayleigh damping ratio coefficient of icing unit in icing transmission lines. Background Technology

[0002] Ice storms on transmission lines are a common natural disaster affecting power grids. These storms can easily trigger phenomena such as transmission line galloping and ice-shedding jumps, and in severe cases, can even lead to flashovers, line breaks, and tower collapses. Currently, line damping is highly sensitive to the response in the problem of transmission line ice-shedding jumps; therefore, using the Rayleigh damping algorithm for parameter setting is often crucial. However, the methods for setting the damping ratios of icing and transmission conductors are not yet clear. Therefore, it is impossible to determine the damping coefficients of icing and transmission lines individually, and consequently, it is impossible to accurately calculate the dynamic response of lines under icing and certain icing conditions. Summary of the Invention

[0003] The purpose of this application is to at least solve one of the aforementioned technical defects, particularly the technical defect in the prior art that cannot determine the damping coefficients of icing and transmission lines, thus making it impossible to accurately calculate the dynamic response of lines under icing and partially icing conditions.

[0004] This application provides a method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line, the method comprising:

[0005] Determine the first transmission line parameters and first damping ratio before icing, and the second transmission line parameters and second damping ratio after icing;

[0006] The first mode frequency of the target transmission line under the first mode before icing is determined based on the first transmission line parameters of the target transmission line, and the second mode frequency of the target transmission line under the second mode after icing is determined based on the second transmission line parameters of the target transmission line.

[0007] The Rayleigh damping algorithm is adopted, and the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing are calculated based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing. The second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing are calculated based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing.

[0008] Using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient before the target transmission line is iced, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated.

[0009] Optionally, the parameters of the first transmission line include horizontal span, horizontal tension before icing, and mass per unit length; the first mode shape includes out-of-plane mode shape; and the frequency of the first mode shape includes out-of-plane vibration frequency.

[0010] The formula for determining the out-of-plane vibration frequency of the target transmission line under the out-of-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows:

[0011]

[0012] In the formula, ω co_n Let H be the nth out-of-plane vibration frequency, L be the horizontal span, and H be the horizontal span. c The horizontal tension before icing, m c This represents the mass per unit length before icing.

[0013] Optionally, the parameters of the first transmission line include horizontal span, horizontal tension before icing, mass per unit length, elastic modulus and cross-sectional area, and the first mode shape includes in-plane mode shape, and the frequency of the first mode shape includes in-plane antisymmetric vibration frequency and in-plane symmetric vibration frequency.

[0014] The formula for determining the in-plane antisymmetric vibration frequency of the target transmission line under the in-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows:

[0015]

[0016] In the formula, w cia_n Let H be the nth in-plane antisymmetric vibration frequency before icing, L be the horizontal span, and H be the frequency of the nth in-plane antisymmetric vibration. c For horizontal tension, m c Mass per unit length;

[0017] The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode shape before icing, based on the horizontal span, horizontal tension before icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows:

[0018]

[0019]

[0020]

[0021] Among them, w cis_n Let H be the nth in-plane symmetrical vibration frequency before icing, L be the horizontal span, and H be the... c The horizontal tension before icing, m c β is the mass per unit length before icing.c_n λ is the root of the nth-order characteristic equation. c E is the Irvine constant. c Let A be the elastic modulus of the target transmission line before icing. c The cross-sectional area of ​​the target transmission line before it becomes covered with ice.

[0022] Optionally, the second transmission line parameters include horizontal span, horizontal tension after icing, and mass per unit length; the second mode shape includes out-of-plane mode shape; and the second mode shape frequency includes out-of-plane vibration frequency.

[0023] The formula for calculating the out-of-plane vibration frequency of the target transmission line under out-of-plane mode after icing, based on the horizontal span, horizontal tension after icing, and mass per unit length, is as follows:

[0024]

[0025] In the formula, ω cio_n Let H be the nth out-of-plane vibration frequency after icing, L be the horizontal span, and H be the horizontal span. ci The horizontal tension after icing, m ci This represents the mass per unit length after icing.

[0026] Optionally, the parameters of the first transmission line include horizontal span, horizontal tension after icing, mass per unit length, elastic modulus and cross-sectional area, and the second mode shape includes in-plane mode shape, and the frequency of the second mode shape includes in-plane asymmetric vibration frequency and in-plane symmetric vibration frequency.

[0027] The formula for determining the in-plane asymmetric vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span of the target transmission line, the horizontal tension after icing, and the mass per unit length, is as follows:

[0028]

[0029] In the formula, w ciia_n Let H be the in-plane asymmetric vibration frequency of the nth order, L be the horizontal span, and H be the horizontal span. ci For horizontal tension, m ci Mass per unit length;

[0030] The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span, horizontal tension after icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows:

[0031]

[0032]

[0033]

[0034] Among them, w ciis_n Let H be the nth in-plane symmetrical vibration frequency after icing, L be the horizontal span, and H be the... ci The horizontal tension after icing, m ci β is the mass per unit length after icing. ci_n λ is the root of the nth-order characteristic equation. ci E is the Irvine constant. c Let A be the elastic modulus of the target transmission line before icing. c The cross-sectional area of ​​the target transmission line before icing, E i Let A be the elastic modulus of the ice layer. i This represents the cross-sectional area of ​​the ice layer.

[0035] Optionally, the formula for calculating the horizontal tension after icing is as follows:

[0036]

[0037] In the formula, q ci q represents the weight of the target transmission line after it becomes icy. ci =(m c +m i )g;q c q is the weight of the target transmission line. c =m c g;E i Let A be the elastic modulus of the ice layer. i The cross-sectional area of ​​ice is calculated using the following formula:

[0038]

[0039] In the formula, b i For ice thickness; r c The radius of the target transmission line.

[0040] Optionally, the step of calculating the third mass damping ratio and the third stiffness damping ratio of the icing unit using the first mass damping ratio and the first stiffness damping ratio before icing of the target transmission line, and the second mass damping ratio and the second stiffness damping ratio after icing, includes:

[0041] Establish mathematical relationships among the stiffness, mass, and damping of the target transmission line before icing, the icing unit, and the target transmission line after icing;

[0042] Based on the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, and the mathematical relationship between stiffness, mass and damping among the three, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated.

[0043] This application also provides a device for determining the Rayleigh damping ratio coefficient of an icing unit in an icing transmission line, comprising:

[0044] The parameter acquisition module is used to determine the first transmission line parameters and the first damping ratio before the target transmission line is iced, and the second transmission line parameters and the second damping ratio after icing.

[0045] The mode frequency calculation module is used to determine the first mode frequency of the target transmission line under the first mode before icing based on the first transmission line parameters of the target transmission line, and to determine the second mode frequency of the target transmission line under the second mode after icing based on the second transmission line parameters of the target transmission line.

[0046] The first damping ratio coefficient determination module is used to use the Rayleigh damping algorithm to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing; and to calculate the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing.

[0047] The second damping ratio determination module is used to calculate the third mass damping ratio and the third stiffness damping ratio of the icing unit using the first mass damping ratio and the first stiffness damping ratio before the target transmission line is iced, and the second mass damping ratio and the second stiffness damping ratio after icing.

[0048] This application also provides a storage medium storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the steps of the method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line as described in any of the above embodiments.

[0049] This application also provides a computer device, including: one or more processors, and memory;

[0050] The memory stores computer-readable instructions, which, when executed by the one or more processors, perform the steps of the method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line as described in any of the above embodiments.

[0051] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0052] This application provides a method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line. After determining the first transmission line parameters and first damping ratio before icing, and the second transmission line parameters and second damping ratio after icing, the method can determine the first mode frequency of the target transmission line under the first vibration mode before icing based on the first transmission line parameters, and determine the second mode frequency of the target transmission line under the second vibration mode after icing based on the second transmission line parameters. This allows the use of the Rayleigh damping algorithm, and the method can be applied based on the first vibration mode before icing, the first mode frequency after icing, and the second mode frequency after icing. The process involves calculating the first mass damping proportional coefficient and the first stiffness damping proportional coefficient of the target transmission line before icing, based on the frequency and the first damping ratio. Then, based on the second mode shape, the second mode shape frequency, and the second damping ratio after icing, the second mass damping proportional coefficient and the second stiffness damping proportional coefficient of the target transmission line after icing are calculated. Finally, using the first mass damping proportional coefficient and the first stiffness damping proportional coefficient before icing, and the second mass damping proportional coefficient and the second stiffness damping proportional coefficient after icing, the third mass damping proportional coefficient and the third stiffness damping proportional coefficient of the icing unit are calculated. This process allows for the calculation of the damping coefficient of the icing unit by using the damping coefficients of the target transmission line before and after icing, thereby enabling accurate calculation of the dynamic response of the line under icing and partial icing conditions. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 A flowchart illustrating a method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line, as provided in an embodiment of this application.

[0055] Figure 2 A schematic flowchart illustrating the calculation of the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit provided in the embodiments of this application.

[0056] Figure 3 A schematic diagram of a device for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line, provided for an embodiment of this application;

[0057] Figure 4 This is a schematic diagram of the internal structure of a computer device provided in an embodiment of this application. Detailed Implementation

[0058] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0059] Currently, the methods for setting the damping ratios of icing and transmission lines are unclear. Therefore, it is impossible to determine the damping coefficients of icing and transmission lines, and consequently, it is impossible to accurately calculate the dynamic response of lines under icing and partial icing conditions. Based on this, this application proposes the following technical solution, as detailed below:

[0060] In one embodiment, such as Figure 1 As shown, Figure 1 A flowchart illustrating a method for determining the Rayleigh damping ratio of an icing unit in an icing power transmission line, provided in an embodiment of this application; this application provides a method for determining the Rayleigh damping ratio of an icing unit in an icing power transmission line, the method including:

[0061] S110: Determine the first transmission line parameters and first damping ratio before icing, and the second transmission line parameters and second damping ratio after icing.

[0062] In this step, when determining the Rayleigh damping ratio of the icing unit in the icing transmission line, the icing transmission line can be taken as the target transmission line. The first transmission line parameters and the first damping ratio of the target transmission line before icing, and the second transmission line parameters and the second damping ratio of the target transmission line after icing can be obtained. In this way, the damping coefficient of the target transmission line before icing can be determined by the first transmission line parameters and the first damping ratio, and the damping coefficient of the target transmission line after icing can be determined by the second transmission line parameters and the second damping ratio.

[0063] The first transmission line parameters of this application include, but are not limited to, the radius, horizontal span, horizontal tension before icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line. The second transmission line parameters can be obtained by collecting parameters such as the thickness of the ice, elastic modulus, self-weight, and cross-sectional area, and calculating these parameters with the first transmission line parameters.

[0064] The first damping ratio before icing and the second damping ratio after icing of the target transmission line in this application can be determined by collecting experimental data or relevant literature. For example, this application can collect the damping ratio before icing and the damping ratio after icing of the transmission line based on transmission line de-icing jump scale experiments, full-scale measurements, or relevant literature. Generally, the damping ratio before icing and the damping ratio after icing of the transmission line are taken as 0.02 and 0.1, respectively.

[0065] S120: Determine the first mode frequency of the target transmission line under the first mode before icing based on the first transmission line parameters of the target transmission line, and determine the second mode frequency of the target transmission line under the second mode after icing based on the second transmission line parameters of the target transmission line.

[0066] In this step, after obtaining the first transmission line parameters and the first damping ratio of the target transmission line before icing, and the second transmission line parameters and the second damping ratio after icing through S110, the first mode frequency of the target transmission line under the first mode before icing can be determined based on the first transmission line parameters, and the second mode frequency of the target transmission line under the second mode after icing can be determined based on the second transmission line parameters. In this way, the damping coefficient of the target transmission line before and after icing can be calculated using the first mode frequency and the second mode frequency, respectively.

[0067] It is understandable that the vibration modes of the target transmission line before and after icing can be divided into in-plane and out-of-plane modes, and the in-plane modes can be further divided into in-plane antisymmetric and in-plane symmetrical modes. Therefore, when calculating the modal frequencies of the target transmission line, this application can calculate the first modal frequency of the target transmission line under the first mode before icing, and the second modal frequency under the second mode after icing. In this way, the Rayleigh damping algorithm can be used for the analysis of structural vibration.

[0068] S130: The Rayleigh damping algorithm is adopted, and the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing are calculated based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing. The second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing are calculated based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing.

[0069] In this step, after determining the first mode frequency of the target transmission line under the first mode before icing and the second mode frequency under the second mode after icing through S120, this application can use the Rayleigh damping algorithm to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing based on the first mode, the first mode frequency and the first damping ratio of the target transmission line before icing, and calculate the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing based on the second mode, the second mode frequency and the second damping ratio of the target transmission line after icing.

[0070] Generally speaking, Rayleigh damping can be divided into mass damping and stiffness damping, and its expression is:

[0071] [C] = α0[M] + α1[K]

[0072] In the formula, [C], [M], and [K] are the damping matrix, mass matrix, and stiffness matrix, respectively, α0 is the mass damping proportionality coefficient, and α1 is the stiffness damping proportionality coefficient.

[0073] Given the damping ratio ξ of any two mode shapes ω1 and ω2, the expressions for α0 and α1 are:

[0074]

[0075]

[0076] For structural vibration analysis, ω1 is often taken as the fundamental frequency of the structure, and ω2 can be selected as the frequency of the highest-order vibration mode that is most likely to occur in the actual dynamic response. After calculating the first mode frequency of the target transmission line under the first vibration mode before icing and the second mode frequency under the second vibration mode after icing, the corresponding first mode frequency and first damping ratio can be selected according to the actual situation to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the corresponding second mode frequency and second damping ratio can be selected to calculate the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing.

[0077] S140: Calculate the third mass damping ratio and the third stiffness damping ratio of the icing unit using the first mass damping ratio and the first stiffness damping ratio before the target transmission line is iced, and the second mass damping ratio and the second stiffness damping ratio after icing.

[0078] In this step, after calculating the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing through S130, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit can be calculated using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing. In this way, the dynamic response of the line under icing and partial icing conditions can be accurately calculated.

[0079] It is understandable that, as can be seen from the above Rayleigh damping expression, to calculate the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit, it is necessary to first determine the Rayleigh damping expressions for the target transmission line before icing, after icing, and the icing unit. Then, using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit can be calculated. Finally, by defining the stiffness damping ratio coefficient and the mass damping ratio coefficient of the transmission line and the icing respectively in the transmission line-icing structure, the Rayleigh damping setting can be completed.

[0080] In the above embodiments, after determining the first transmission line parameters and the first damping ratio before icing, and the second transmission line parameters and the second damping ratio after icing, the first mode frequency of the target transmission line under the first mode shape before icing can be determined based on the first transmission line parameters, and the second mode frequency of the target transmission line under the second mode shape after icing can be determined based on the second transmission line parameters. Thus, the Rayleigh damping algorithm can be used to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing based on the first mode shape, the first mode frequency, and the first damping ratio before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing based on the second mode shape, the second mode frequency, and the second damping ratio after icing. Finally, using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated. This process can calculate the damping coefficient of the icing unit by using the damping coefficient of the target transmission line before and after icing, and thus accurately calculate the dynamic response of the line under icing and partial icing conditions.

[0081] In one embodiment, the first transmission line parameters include horizontal span, horizontal tension before icing, and mass per unit length, the first mode shape includes an out-of-plane mode shape, and the first mode shape frequency includes an out-of-plane vibration frequency.

[0082] The formula for determining the out-of-plane vibration frequency of the target transmission line under the out-of-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows:

[0083]

[0084] In the formula, ω co_n Let H be the nth out-of-plane vibration frequency, L be the horizontal span, and H be the horizontal span. c The horizontal tension before icing, m c This represents the mass per unit length before icing.

[0085] In one embodiment, the first transmission line parameters include horizontal span, horizontal tension before icing, mass per unit length, elastic modulus, and cross-sectional area; the first mode shape includes in-plane mode shape; and the first mode shape frequency includes in-plane antisymmetric vibration frequency and in-plane symmetric vibration frequency.

[0086] The formula for determining the in-plane antisymmetric vibration frequency of the target transmission line under the in-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows:

[0087]

[0088] In the formula, w cia_n Let H be the nth in-plane antisymmetric vibration frequency before icing, L be the horizontal span, and H be the frequency of the nth in-plane antisymmetric vibration. c For horizontal tension, m c Mass per unit length;

[0089] The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode shape before icing, based on the horizontal span, horizontal tension before icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows:

[0090]

[0091]

[0092]

[0093] Among them, w cis_n Let H be the nth in-plane symmetrical vibration frequency before icing, L be the horizontal span, and H be the... c The horizontal tension before icing, m cβ is the mass per unit length before icing. c_n λ is the root of the nth-order characteristic equation. c E is the Irvine constant. c Let A be the elastic modulus of the target transmission line before icing. c The cross-sectional area of ​​the target transmission line before it becomes covered with ice.

[0094] In one embodiment, the second transmission line parameters include horizontal span, horizontal tension after icing, and mass per unit length; the second mode shape includes an out-of-plane mode shape; and the second mode shape frequency includes an out-of-plane vibration frequency.

[0095] The formula for calculating the out-of-plane vibration frequency of the target transmission line under out-of-plane mode after icing, based on the horizontal span, horizontal tension after icing, and mass per unit length, is as follows:

[0096]

[0097] In the formula, ω cio_n Let H be the nth out-of-plane vibration frequency after icing, L be the horizontal span, and H be the horizontal span. ci The horizontal tension after icing, m ci This represents the mass per unit length after icing.

[0098] In one embodiment, the first transmission line parameters include horizontal span, horizontal tension after icing, mass per unit length, elastic modulus, and cross-sectional area; the second mode shape includes in-plane mode shape; and the second mode shape frequency includes in-plane asymmetric vibration frequency and in-plane symmetric vibration frequency.

[0099] The formula for determining the in-plane asymmetric vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span of the target transmission line, the horizontal tension after icing, and the mass per unit length, is as follows:

[0100]

[0101] In the formula, w ciia_n Let H be the in-plane asymmetric vibration frequency of the nth order, L be the horizontal span, and H be the horizontal span. ci For horizontal tension, m ci Mass per unit length;

[0102] The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span, horizontal tension after icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows:

[0103]

[0104]

[0105]

[0106] Among them, w ciis_n Let H be the nth in-plane symmetrical vibration frequency after icing, L be the horizontal span, and H be the... ci The horizontal tension after icing, m ci β is the mass per unit length after icing. ci_n λ is the root of the nth-order characteristic equation. ci E is the Irvine constant. c Let A be the elastic modulus of the target transmission line before icing. c The cross-sectional area of ​​the target transmission line before icing, E i Let A be the elastic modulus of the ice layer. i This represents the cross-sectional area of ​​the ice layer.

[0107] Furthermore, after calculating the vibration frequencies of the target transmission line under out-of-plane modes, in-plane antisymmetric vibration frequencies and in-plane symmetric vibration frequencies under in-plane modes before icing, and the vibration frequencies of the target transmission line under out-of-plane modes, in-plane asymmetric vibration frequencies and in-plane symmetric vibration frequencies under in-plane modes after icing, this application can substitute the first vibration frequency and the first damping ratio of the target transmission line in the first two or more stages before icing into the formulas for the mass damping proportional coefficient and the stiffness damping proportional coefficient, respectively, to obtain the first mass damping proportional coefficient and the first stiffness damping proportional coefficient of the target transmission line before icing; this application can also substitute the second vibration frequency and the second damping ratio of the target transmission line in the first two or more stages after icing into the formulas for the mass damping proportional coefficient and the stiffness damping proportional coefficient, respectively, to obtain the second mass damping proportional coefficient and the second stiffness damping proportional coefficient of the target transmission line after icing.

[0108] In one embodiment, the formula for calculating the horizontal tension after icing is as follows:

[0109]

[0110] In the formula, q ci q represents the weight of the target transmission line after it becomes icy. ci =(m c +m i )g;q c q is the weight of the target transmission line. c =m c g;E i Let A be the elastic modulus of the ice layer. i The cross-sectional area of ​​ice is calculated using the following formula:

[0111] A i =π(b) i2 +2r c b i )

[0112] In the formula, b i For ice thickness; r c The radius of the target transmission line.

[0113] In one embodiment, such as Figure 2 As shown, Figure 2 The flowchart illustrating the calculation of the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit provided in this application embodiment is as follows: S140, using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, to calculate the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit, may include:

[0114] S141: Establish the mathematical relationships of stiffness, mass, and damping among the target transmission line before icing, the icing unit, and the target transmission line after icing.

[0115] S142: Based on the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, and the mathematical relationship between stiffness, mass and damping among the three, calculate the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit.

[0116] In this embodiment, when calculating the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit, the mathematical relationship between stiffness, mass, and damping among the target transmission line before icing, the icing unit, and the target transmission line after icing can be established first. Then, based on the first mass damping ratio coefficient and the first stiffness damping ratio coefficient before icing, the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, and the mathematical relationship between stiffness, mass, and damping among the three, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit can be calculated.

[0117] In one specific implementation, for better representation, the subscript c will represent the target transmission line before icing, the subscript i will represent the icing unit, and the subscript ci will represent the target transmission line after icing.

[0118] Due to the use of the Rayleigh damping matrix, the damping of the target transmission line before icing, the icing unit, and the target transmission line after icing in this application can be expressed as:

[0119] [C c ]=α 0c [M c ]+α1c [K c (1)

[0120] [C i ]=α 0i [M i ]+α 1i [K i (2)

[0121] [C ci ]=α 0ci [M ci ]+α 1ci [K ci (3)

[0122] In the numerical simulation, the transmission line unit and the icing unit share nodes, and both slip, meaning their deformation and displacement are the same. Therefore, it is not difficult to deduce the mass relationship between the target transmission line before icing, the icing unit, and the target transmission line after icing as follows:

[0123] [M ci ] = [M c ]+[M i (4)

[0124] The damping relationship is as follows:

[0125] [C ci ] = [C c ]+[C i (5)

[0126] Stiffness is defined as the force corresponding to a unit displacement. Since the deformation and displacement of the target transmission line and the icing unit are the same, the stiffness relationship is as follows:

[0127] [K ci ] = [K c ]+[K i (6)

[0128] It is understandable that, in the dynamics of in-plane vibration, this application can derive the stiffness relationship between the target transmission line and the icing element by the vertical load components borne by the icing element and the target transmission line respectively under load.

[0129] Next, this application can solve for the vertical stiffness relationship between the target transmission line before icing, the icing element, and the target transmission line after icing. This process can be converted into a uniformly distributed load q. e When the same vertical displacement is generated under the action, the relationship between the uniformly distributed load components borne by the target transmission line before icing, the icing unit, and the target transmission line after icing is expressed as:

[0130] q e =qec +q ei (7)

[0131] In the formula, q e The total uniformly distributed load borne by the target transmission line after icing, q ec The uniformly distributed load component borne by the target transmission line before icing, q ei The uniformly distributed load component borne by the icing unit.

[0132] Since the target transmission line before icing is in close contact with the icing unit, and the strain of the target transmission line before icing and the icing unit is the same under load, it can be deduced that:

[0133]

[0134] In the formula, ΔH c ΔH represents the increase in horizontal tension of the target transmission line before icing under load. i This represents the horizontal tension increment of the icing unit under load.

[0135] Furthermore, since the target transmission line and the icing do not slip, their relative positions remain unchanged. From geometric relationships and mechanical equilibrium conditions, we can conclude that:

[0136]

[0137] We can calculate from formulas (8) and (9):

[0138]

[0139] From formula (10), the vertical stiffness relationship between the target transmission line before icing and the icing unit is as follows:

[0140]

[0141] The mass relationship between the target transmission line before icing and the icing unit is as follows:

[0142]

[0143] By combining formulas (1) to (6), (11), and (12), the third stiffness damping proportionality coefficient α of the icing element can be obtained. 1i and the third mass damping proportionality coefficient α 0i :

[0144]

[0145]

[0146] Finally, by defining the stiffness damping ratio coefficient and mass damping ratio coefficient of the transmission line and the icing respectively in the transmission line-icing structure, the Rayleigh damping can be set.

[0147] The following describes the apparatus for determining the Rayleigh damping ratio of the icing unit in an icing power transmission line provided in the embodiments of this application. The apparatus for determining the Rayleigh damping ratio of the icing unit in an icing power transmission line described below can be referred to in correspondence with the method for determining the Rayleigh damping ratio of the icing unit in an icing power transmission line described above.

[0148] In one embodiment, such as Figure 3 As shown, Figure 3 This application provides a schematic diagram of a device for determining the Rayleigh damping ratio of an icing unit in an icing power transmission line, as provided in an embodiment of the present application. The application also provides a device for determining the Rayleigh damping ratio of an icing unit in an icing power transmission line, which may include a parameter acquisition module 210, a mode shape frequency calculation module 220, a first damping ratio determination module 230, and a second damping ratio determination module 240, specifically including the following:

[0149] The parameter acquisition module 210 is used to determine the first transmission line parameters and the first damping ratio before the target transmission line is iced, and the second transmission line parameters and the second damping ratio after icing.

[0150] The mode frequency calculation module 220 is used to determine the first mode frequency of the target transmission line under a first mode before icing based on the first transmission line parameters of the target transmission line, and to determine the second mode frequency of the target transmission line under a second mode after icing based on the second transmission line parameters of the target transmission line.

[0151] The first damping ratio determination module 230 is used to calculate the first mass damping ratio and the first stiffness damping ratio of the target transmission line before icing based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing, using the Rayleigh damping algorithm, and to calculate the second mass damping ratio and the second stiffness damping ratio of the target transmission line after icing based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing.

[0152] The second damping ratio determination module 240 is used to calculate the third mass damping ratio and the third stiffness damping ratio of the icing unit using the first mass damping ratio and the first stiffness damping ratio before the target transmission line is iced, and the second mass damping ratio and the second stiffness damping ratio after icing.

[0153] In the above embodiments, after determining the first transmission line parameters and the first damping ratio before icing, and the second transmission line parameters and the second damping ratio after icing, the first mode frequency of the target transmission line under the first mode shape before icing can be determined based on the first transmission line parameters, and the second mode frequency of the target transmission line under the second mode shape after icing can be determined based on the second transmission line parameters. Thus, the Rayleigh damping algorithm can be used to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing based on the first mode shape, the first mode frequency, and the first damping ratio before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing based on the second mode shape, the second mode frequency, and the second damping ratio after icing. Finally, using the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, and the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated. This process can calculate the damping coefficient of the icing unit by using the damping coefficient of the target transmission line before and after icing, and thus accurately calculate the dynamic response of the line under icing and partial icing conditions.

[0154] In one embodiment, this application also provides a storage medium storing computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing transmission line as described in any of the above embodiments.

[0155] In one embodiment, this application also provides a computer device, including: one or more processors, and memory.

[0156] The memory stores computer-readable instructions, which, when executed by the one or more processors, perform the steps of the method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line as described in any of the above embodiments.

[0157] Indicatively, such as Figure 4 As shown, Figure 4 This is a schematic diagram of the internal structure of a computer device 300 provided in an embodiment of this application. The computer device 300 can be provided as a server. (Refer to...) Figure 4The computer device 300 includes a processing component 302, which further includes one or more processors, and memory resources represented by memory 301 for storing instructions, such as application programs, that can be executed by the processing component 302. The application programs stored in memory 301 may include one or more modules, each corresponding to a set of instructions. Furthermore, the processing component 302 is configured to execute instructions to perform the method for determining the Rayleigh damping ratio coefficient of the icing unit in the icing transmission line of any of the above embodiments.

[0158] The computer device 300 may also include a power supply component 303 configured to perform power management of the computer device 300, a wired or wireless network interface 304 configured to connect the computer device 300 to a network, and an input / output (I / O) interface 305. The computer device 300 may operate on an operating system stored in memory 301, such as Windows Server™, Mac OS X™, Unix™, Linux™, Free BSD™, or similar.

[0159] Those skilled in the art will understand that Figure 4 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0160] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0161] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0162] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line, characterized in that, The method includes: Determine the first transmission line parameters and first damping ratio before icing, and the second transmission line parameters and second damping ratio after icing; The first mode frequency of the target transmission line under the first mode before icing is determined based on the first transmission line parameters of the target transmission line, and the second mode frequency of the target transmission line under the second mode after icing is determined based on the second transmission line parameters of the target transmission line. The Rayleigh damping algorithm is adopted, and the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing are calculated based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing. The second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing are calculated based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing. Using the first mass damping proportional coefficient and the first stiffness damping proportional coefficient of the target transmission line before icing, and the second mass damping proportional coefficient and the second stiffness damping proportional coefficient after icing, the third mass damping proportional coefficient and the third stiffness damping proportional coefficient of the icing unit are calculated, including: Establish mathematical relationships among the stiffness, mass, and damping of the target transmission line before icing, the icing unit, and the target transmission line after icing; Based on the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, and the mathematical relationship between stiffness, mass and damping among the three, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated.

2. The method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing transmission line according to claim 1, characterized in that, The first transmission line parameters include horizontal span, horizontal tension before icing, and mass per unit length; the first mode shape includes out-of-plane mode shape; and the first mode shape frequency includes out-of-plane vibration frequency. The formula for determining the out-of-plane vibration frequency of the target transmission line under the out-of-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows: In the formula, For the first n Out-of-plane vibration frequency, L For horizontal spacing, H c The horizontal tension before icing. m c This represents the mass per unit length before icing.

3. The method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line according to claim 1 or 2, characterized in that, The first transmission line parameters include horizontal span, horizontal tension before icing, mass per unit length, elastic modulus and cross-sectional area; the first mode shape includes in-plane mode shape; the first mode shape frequency includes in-plane antisymmetric vibration frequency and in-plane symmetric vibration frequency. The formula for determining the in-plane antisymmetric vibration frequency of the target transmission line under the in-plane vibration mode before icing, based on the horizontal span, horizontal tension before icing, and mass per unit length, is as follows: In the formula, Before the ice cover n In-plane antisymmetric vibration frequency, L For horizontal spacing, H c The horizontal tension before icing. m c Mass per unit length; The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode shape before icing, based on the horizontal span, horizontal tension before icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows: in, Before the ice cover n In-plane symmetrical vibration frequency, L For horizontal spacing, H c The horizontal tension before icing. m c The mass per unit length before icing. For the first n The roots of the first-order characteristic equation, λ c It is the Irvine constant. E c The elastic modulus of the target power transmission line before icing. A c The cross-sectional area of ​​the target transmission line before it becomes covered with ice.

4. The method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line according to claim 1, characterized in that, The second transmission line parameters include horizontal span, horizontal tension after icing, and mass per unit length; the second mode shape includes out-of-plane mode shape; and the second mode shape frequency includes out-of-plane vibration frequency. The formula for calculating the out-of-plane vibration frequency of the target transmission line under out-of-plane mode after icing, based on the horizontal span, horizontal tension after icing, and mass per unit length, is as follows: In the formula, For the first time after the ice was covered n Out-of-plane vibration frequency, L For horizontal spacing, The horizontal tension after icing. This represents the mass per unit length after icing.

5. The method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line according to claim 1 or 4, characterized in that, The first transmission line parameters include horizontal span, horizontal tension after icing, mass per unit length, elastic modulus and cross-sectional area; the second mode shape includes in-plane mode shape; and the second mode shape frequency includes in-plane asymmetric vibration frequency and in-plane symmetric vibration frequency. The formula for determining the in-plane asymmetric vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span of the target transmission line, the horizontal tension after icing, and the mass per unit length, is as follows: In the formula, For the first n In-plane asymmetric vibration frequency, L For horizontal spacing, The horizontal tension after icing. Mass per unit length; The formula for determining the in-plane symmetrical vibration frequency of the target transmission line under the in-plane mode after icing, based on the horizontal span, horizontal tension after icing, mass per unit length, elastic modulus, and cross-sectional area of ​​the target transmission line, is as follows: in, For the first time after the ice was covered n In-plane symmetrical vibration frequency, L For horizontal spacing, The horizontal tension after icing. The mass per unit length after icing. For the first n The roots of the first-order characteristic equation, λ ci It is the Irvine constant. E c The elastic modulus of the target power transmission line before icing. A c The cross-sectional area of ​​the target transmission line before icing. E i The elastic modulus of the ice layer. A i Let be the cross-sectional area of ​​the ice layer. H c The horizontal tension before icing.

6. The method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line according to claim 5, characterized in that, The formula for calculating the horizontal tension after icing is as follows: In the formula, q ci The target power transmission line's own weight after being covered with ice. q ci = ( m c + m i ) g ; q c The weight of the transmission line itself. q c =m c g ; E i The elastic modulus of the ice layer. A i The cross-sectional area of ​​ice is calculated using the following formula: In the formula, b i The ice is thick; r c The radius of the target transmission line.

7. A device for determining the Rayleigh damping ratio coefficient of an icing unit in an icing power transmission line, characterized in that, include: The parameter acquisition module is used to determine the first transmission line parameters and the first damping ratio before the target transmission line is iced, and the second transmission line parameters and the second damping ratio after icing. The mode frequency calculation module is used to determine the first mode frequency of the target transmission line under the first mode before icing based on the first transmission line parameters of the target transmission line, and to determine the second mode frequency of the target transmission line under the second mode after icing based on the second transmission line parameters of the target transmission line. The first damping ratio coefficient determination module is used to use the Rayleigh damping algorithm to calculate the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing based on the first mode shape, the first mode shape frequency and the first damping ratio of the target transmission line before icing; and to calculate the second mass damping ratio coefficient and the second stiffness damping ratio coefficient of the target transmission line after icing based on the second mode shape, the second mode shape frequency and the second damping ratio of the target transmission line after icing. The second damping ratio determination module is used to calculate the third mass damping ratio and the third stiffness damping ratio of the icing unit using the first mass damping ratio and the first stiffness damping ratio before icing of the target transmission line, and the second mass damping ratio and the second stiffness damping ratio after icing. This includes: Establish mathematical relationships among the stiffness, mass, and damping of the target transmission line before icing, the icing unit, and the target transmission line after icing; Based on the first mass damping ratio coefficient and the first stiffness damping ratio coefficient of the target transmission line before icing, the second mass damping ratio coefficient and the second stiffness damping ratio coefficient after icing, and the mathematical relationship between stiffness, mass and damping among the three, the third mass damping ratio coefficient and the third stiffness damping ratio coefficient of the icing unit are calculated.

8. A storage medium, characterized in that: The storage medium stores computer-readable instructions that, when executed by one or more processors, cause the one or more processors to perform the steps of the method for determining the Rayleigh damping ratio coefficient of an icing unit in an icing transmission line as described in any one of claims 1 to 6.

9. A computer device, characterized in that, include: One or more processors, and memory; The memory stores computer-readable instructions, which, when executed by the one or more processors, perform the steps of the method for determining the Rayleigh damping ratio coefficient of the icing unit in an icing transmission line as described in any one of claims 1 to 6.

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