Method and system for calculating audible noise of an ehv single circuit ac transmission line

Abstract

The application provides a method and system for calculating audible noise of an ultrahigh voltage single-circuit AC transmission line. The method and system equivalently regard the ultrahigh voltage single-circuit transmission line as a long straight charge element, meanwhile, the height H of the long straight charge element from the ground is determined according to the equivalence rationality m0 , the solving in a three-dimensional environment is reduced to a two-dimensional plane, and the surface potential gradient and the sound power level of the charge point are determined according to the voltage and the maximum sag of the transmission line m0 , the conductor parameters of the multi-bundle conductor used by the transmission line, and finally the audible noise of any point in the two-dimensional plane is calculated according to the sound power level of the charge point element and the height H m0 . Compared with the prior art, the method and system reduce the model in a three-dimensional environment to a two-dimensional plane, the mathematical model obtained is simpler, and the solving speed is greatly improved under the premise of ensuring that the solving result conforms to the engineering practice.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic environment in power transmission and transformation engineering, and more specifically, to a method and system for calculating audible noise in ultra-high voltage single-circuit AC transmission lines. Background Technology

[0002] The electromagnetic environment of AC transmission lines is receiving increasing attention. Consequently, relevant standards and parameter limits for the electromagnetic environment of AC transmission lines are becoming increasingly standardized, contributing to the standardization of transmission engineering design. Audible noise, as one of the electromagnetic environment parameters, has clearly defined voltage level limits in transmission line electromagnetic environment standards. Therefore, for AC transmission lines not yet under construction, it is essential to perform audible noise simulation calculations against these limits to determine whether the design dimensions of the AC transmission line may exceed the limits. Similarly, for AC transmission lines already in operation, it is also necessary to perform audible noise simulation calculations on the existing conductor parameters to determine whether the AC transmission line may exceed the limits under actual operating conditions.

[0003] However, existing technologies all involve simulating the audible noise of ultra-high voltage single-circuit AC transmission lines in a three-dimensional environment, which is labor-intensive, complex, and inefficient. Summary of the Invention

[0004] To address the problems of high workload, complex simulation calculations, and low efficiency in simulating the audible noise of ultra-high voltage single-circuit AC transmission lines in a three-dimensional environment, this invention provides a method for calculating the audible noise of ultra-high voltage single-circuit AC transmission lines. The method includes:

[0005] The catenary model of the m-phase transmission line in an ultra-high voltage single-circuit AC transmission line is equivalent to the m-th long straight charge element, where 1≤m≤Z, and Z is the number of phases of the single-circuit AC transmission line.

[0006] The m-th long straight charge element in a three-dimensional environment is equivalent to the m-th charge point element in a two-dimensional plane, and the ground is equivalent to a straight line, where the height H of the m-th charge point element above the ground is... m0 Take the height of the lowest point of the sag of the m-phase transmission line from the ground.

[0007] The equivalent radius r of the multi-split conductor is calculated based on the number of conductor splits n, the diameter d of each sub-conductor, and the diameter b of each split conductor used in ultra-high voltage single-circuit AC transmission lines. eq ;

[0008] Based on the voltage U of the m-phase transmission line corresponding to the m-th charge point element m and maximum sag C mmax The height H m0and the equivalent radius r of the multi-bundled conductor eq calculating the surface potential gradient g of the mth charge point element av (m) ;

[0009] calculating the surface potential gradient g of the mth charge point element according to the surface potential gradient g of the mth charge point element av (m) and the equivalent radius r of the multi-bundled conductor eq calculating the sound power level PWL(m) of the mth charge point element

[0010] calculating the sound power level PWL(m) of the mth charge point element according to the sound power level PWL(m) of the mth charge point element and the height H m0 and the vertical distance δ of the straight line representing the ground from any point in the two-dimensional plane, calculating the excess pressure single-circuit AC transmission line audible noise SLA of the point.

[0011] Optionally, the equivalent radius r of the multi-bundled conductor is calculated according to the number of bundled conductors n, the diameter d of each sub-conductor and the diameter b of the bundled conductor of the multi-bundled conductor used in the excess pressure single-circuit AC transmission line eq wherein the equivalent radius r of the multi-bundled conductor eq is calculated according to the following formula:

[0012]

[0013] wherein the units of d and b are mm.

[0014] Optionally, the surface potential gradient g of the mth charge point element is calculated according to the voltage U of the mth phase transmission line corresponding to the mth charge point element m and the maximum sag C mmax , the height H m0 and the equivalent radius r of the multi-bundled conductor eq av (m), which is calculated according to the following formula:

[0015]

[0016] H m1 = H m0 + C mmax / 3

[0017] wherein the units of C mmax , H m0 and H m1 are m, and the unit of g av (m) is kV / cm.

[0018] Optionally, the surface potential gradient g of the mth charge point element is calculated according to the surface potential gradient g of the mth charge point element av (m) and the equivalent radius r of the multi-bundled conductor eq ​The sound power level PWL(m) of the mth charge point element is calculated according to the following formula:

[0019] PWL(m) = -164.6 + 120lgg av (m) + 55lgr eq .

[0020] Optionally, the audible noise SLA of the EHV single-circuit AC transmission line at an arbitrary point in a two-dimensional plane is calculated according to the sound power level PWL(m) of the mth charge point element and the vertical distance δ of the point to a straight line representing the ground. m0

[0021]

[0022] In the formula, SLA is the A-weighted sound level, and the unit is dB.

[0023] According to another aspect of the present application, the present application provides a system for calculating the audible noise of an EHV single-circuit AC transmission line, the system comprising:

[0024] A first equivalent unit is configured to equivalently convert a catenary model of an mth phase transmission line in an EHV single-circuit AC transmission line into an mth long straight charge element, wherein 1≤m≤Z, and Z is the number of phases of the single-circuit AC transmission line.

[0025] A second equivalent unit is configured to equivalently convert the mth long straight charge element in a three-dimensional environment into an mth charge point element in a two-dimensional plane, and equivalently convert the ground into a straight line, wherein the mth charge point element is at a height H m0 from the ground.

[0026] A first calculation unit is configured to calculate an equivalent radius r eq of a multi-bundled conductor according to the number n of bundled conductors, the diameter d of each sub-conductor, and the diameter b of the bundled conductor of the multi-bundled conductor used in the EHV single-circuit AC transmission line.

[0027] A second calculation unit is configured to calculate a surface electric potential gradient g m (m) of the mth charge point element according to a voltage U mmax of the mth phase transmission line corresponding to the mth charge point element, a maximum sag C m0 , the height H eq , and the equivalent radius r av of the multi-bundled conductor.

[0028] A third calculation unit is configured to calculate a surface electric potential gradient g av (m) of the mth charge point element according to the surface electric potential gradient g eq ​calculating the sound power level PWL(m) of the mth charge point element;

[0029] a result output unit configured to calculate the audible noise SLA of the ultra-high voltage single-circuit AC transmission line at an arbitrary point in a two-dimensional plane according to the sound power level PWL(m) of the mth charge point element, the height H m0 and the perpendicular distance δ of a straight line representing the ground from the arbitrary point in the two-dimensional plane.

[0030] Optionally, the first calculation unit is configured to calculate the equivalent radius r of the multi-bundled conductor according to the number of bundled conductors n, the diameter d of each sub-conductor and the diameter b of the bundled conductor used in the ultra-high voltage single-circuit AC transmission line eq wherein the equivalent radius r of the multi-bundled conductor is calculated according to the following formula: eq

[0031]

[0032] wherein the units of d and b are mm.

[0033] Optionally, the second calculation unit is configured to calculate the surface potential gradient g(m) of the mth charge point element according to the voltage U m of the mth phase transmission line corresponding to the mth charge point element, the maximum sag C mmax , the height H m0 and the equivalent radius r of the multi-bundled conductor eq av wherein the surface potential gradient g(m) of the mth charge point element is calculated according to the following formula:

[0034]

[0035] H m1 = H m0 + C mmax / 3

[0036] wherein the units of C mmax , H m0 and H m1 are m, and the unit of g av (m) is kV / cm.

[0037] Optionally, the third calculation unit is configured to calculate the sound power level PWL(m) of the mth charge point element according to the surface potential gradient g av (m) of the mth charge point element and the equivalent radius r of the multi-bundled conductor eq

[0038] PWL(m) = -164.6 + 120lgg av (m) + 55lgr eq .

[0039] ​​​Optionally, the result output unit calculates audible noise SLA of the super-high voltage single-circuit AC power transmission line according to the sound power level PWL(m) of the mth charge point element and the height H m0 , and the vertical distance delta of any point in the two-dimensional plane to the straight line representing the ground, the audible noise SLA of the point is calculated.

[0040]

[0041] In the formula, SLA is the A-weighted sound level, and the unit is dB.

[0042] The method and system for calculating audible noise of the super-high voltage single-circuit AC power transmission line provided by the technical scheme of the application equivalently regard the super-high voltage single-circuit AC power transmission line as a long straight charge element, and simultaneously, the height H m0 , the height H m0 , and the equivalent radius of the multi-bundle conductor is calculated according to the conductor parameters of the multi-bundle conductor used by the power transmission line, the surface potential gradient of the charge point element is determined according to the surface potential gradient and the equivalent radius of the multi-bundle conductor, the sound power level of the charge point element is determined according to the surface potential gradient and the equivalent radius of the multi-bundle conductor, and finally, the audible noise of any point in the two-dimensional plane is calculated according to the sound power level of the charge point element and the height H m0 The method and system and the prior art are compared, the model in the three-dimensional environment is reduced to the two-dimensional plane, the mathematical model obtained is simpler, and the solving speed is greatly improved on the premise that the solving result meets the engineering practice. BRIEF DESCRIPTION OF DRAWINGS

[0043] The exemplary embodiments of the application can be more completely understood by reference to the following drawings:

[0044] Figure 1 The flow chart of the method for calculating audible noise of the super-high voltage single-circuit AC power transmission line according to the preferred embodiment of the application is shown in the figure.

[0045] Figure 2 The equivalent diagram of the power transmission line according to the preferred embodiment of the application is shown in the figure.

[0046] Figure 3 The structure schematic diagram of the system for calculating audible noise of the super-high voltage single-circuit AC power transmission line according to the preferred embodiment of the application is shown in the figure. DETAILED DESCRIPTION

[0047] Reference will now be made to the drawings to describe the exemplary embodiments of the present application in greater detail. The present application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art. Like numbers refer to like elements throughout the description of the figures. In the drawings, the same elements have the same reference numerals.

[0048] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

[0049] Figure 1 A flow chart of a method for calculating audible noise of an extra-high voltage single-circuit AC power transmission line according to a preferred embodiment of the present application. As shown in Figure 1 the method for calculating audible noise of an extra-high voltage single-circuit AC power transmission line according to the preferred embodiment of the present application starts from step 101.

[0050] In step 101, a catenary model of an mth phase power transmission line in the extra-high voltage single-circuit AC power transmission line is equivalent to an mth long straight charge element, where 1≤m≤Z, and Z is the number of phases of the single-circuit AC power transmission line.

[0051] Figure 2 An equivalent diagram of a power transmission line according to a preferred embodiment of the present application. As shown in Figure 2 the geometry of the conductors of the extra-high voltage single-circuit AC power transmission line is a catenary model. Since this geometry is not the geometry of a standard electrical model, the physical model of this geometry needs to be segmented and refined for each conductor in a real three-dimensional engineering structure before numerical calculation can be performed with the aid of a theoretical model. The prior art generally uses an equal-length "straight segment" model in the standard electrical model for segmentation simulation. Each catenary-form conductor is artificially divided into multiple (assuming N) "straight segment charge elements", each with a length of l and a cross-sectional radius of r. For a single-circuit power transmission line, the calculation complexity of this segmentation simulation is O(3N), where N represents the number of segments of each conductor.

[0052] The simulation engineering progress of actual engineering requirements is often 1 m, so the length of the straight segment charge element needs to be controlled within a range of less than or equal to 0.5 m. With a typical engineering span of 300 m, the simulation calculation complexity is O(3*300 / 0.5), which is approximately O(2000).

[0053] To improve simulation efficiency and ensure consistent simulation results, this preferred embodiment employs a "dimensionality reduction optimization" method to perform equivalent simulations on the aforementioned actual engineering model, i.e., as follows: Figure 2 As shown, the conductor in the entire span is equivalent to a "long straight charge element", the length of which is equal to the span, and the radius of which is the equivalent radius of the conductor. Through the above equivalent method, the computational complexity is O(3), which is 1000 times more efficient than the former.

[0054] In step 102, the m-th long straight charge element in the three-dimensional environment is equivalent to the m-th charge point element in the two-dimensional plane, and the ground is equivalent to a straight line, where the height H of the m-th charge point element above the ground is... m0 Take the height of the lowest point of the sag of the m-phase transmission line from the ground.

[0055] After equating the conductor to a long straight charge element, considering that the actual engineering model of the conductor is a catenary model that meets engineering requirements, it is necessary to consider the rationality of using a single "long straight charge element" to represent the entire conductor. Therefore, if... Figure 2 As shown in the diagram, this embodiment finds the most reasonable equivalent solution by adjusting the height H of the "long straight charge element" from the ground. This preferred embodiment iterates through all heights within the range from the ground to the tower, comparing each result with the simulation results of the actual engineering model without dimensionality reduction optimization, and obtains that the equivalent height of the long straight charge element from the ground is the height H of the lowest point of the conductor sag from the ground. m0 This can be perfectly equivalent. Therefore, when the height H of the equivalent long straight charge element above the ground is determined... m0 After that, the actual engineering model can be optimized from a three-dimensional environment to a two-dimensional environment. By further equating the long straight charge to a charge point element on a two-dimensional plane and simulating the charge point element, the audible noise of the transmission line can be accurately solved.

[0056] In step 103, the equivalent radius r of the multi-split conductor is calculated based on the number of conductor splits n, the diameter d of each sub-conductor, and the diameter b of the split conductors used in the ultra-high voltage single-circuit AC transmission line. eq .

[0057] Preferably, the equivalent radius r of the multi-split conductor is calculated based on the number of conductor splits n, the diameter d of each sub-conductor, and the diameter b of the split conductors used in the ultra-high voltage single-circuit AC transmission line. eq Among them, the equivalent radius r of the multi-split conductor eq The calculation formula is:

[0058]

[0059] In the formula, the units of d and b are mm.

[0060] In step 104, based on the voltage U of the m-phase transmission line corresponding to the m-th charge point element... m and maximum sag C mmax The height H m0 And the equivalent radius r of the multi-split conductor. eq Calculate the surface potential gradient g of the m-th charge point element. av (m).

[0061] Preferably, the voltage U of the m-phase transmission line corresponding to the m-th charge point element is used. m and maximum sag C mmax The height H m0 And the equivalent radius r of the multi-split conductor. eq Calculate the surface potential gradient g of the m-th charge point element. av (m), its calculation formula is:

[0062]

[0063] H m1 =H m0 +C mmax / 3

[0064] In the formula, C mmax H m0 and H m1 The unit is m, g av The unit of (m) is kV / cm.

[0065] In step 105, based on the surface potential gradient g of the m-th charge point element... av (m) and the equivalent radius r of the multi-split conductor eq Calculate the acoustic power level PWL(m) of the m-th charge point element.

[0066] Preferably, based on the surface potential gradient g of the m-th charge point element av (m) and the equivalent radius r of the multi-split conductor eq The sound power level PWL(m) of the m-th charge point element is calculated using the following formula:

[0067] PWL(m) = -164.6 + 120lgg av (m)+55lgr eq .

[0068] In step 106, based on the acoustic power level PWL(m) of the m-th charge point element and the height H... m0and the vertical distance δ of any point in a two-dimensional plane to a straight line representing the ground, to calculate the excess height of the point.

[0069] Preferably, the sound power level PWL(m) of the mth charge point element and the height H m0 and the vertical distance δ of any point in a two-dimensional plane to a straight line representing the ground, to calculate the excess height of the point.

[0070]

[0071] In the formula, SLA is the A-weighted sound level, in dB.

[0072] Figure 3 A schematic diagram of the system for calculating the audible noise of the ultra-high voltage single-circuit AC transmission line according to the preferred embodiment of the present application. As Figure 3 shown, the system for calculating the audible noise of the ultra-high voltage single-circuit AC transmission line according to the preferred embodiment of the present application comprises:

[0073] A first equivalent unit 301 for equivalently converting the catenary model of the mth phase transmission line in the ultra-high voltage single-circuit AC transmission line into a long straight charge element, wherein 1≤m≤Z, and Z is the number of phases of the single-circuit AC transmission line.

[0074] A second equivalent unit 302 for equivalently converting the mth long straight charge element in a three-dimensional environment into an mth charge point element in a two-dimensional plane, and equivalently converting the ground into a straight line, wherein the height H m0 of the mth charge point element to the ground is H

[0075] A first calculation unit 303 for calculating the equivalent radius r eq of the multi-bundled conductor according to the number of bundled conductors n, the diameter d of each sub-conductor, and the diameter b of the bundled conductor of the multi-bundled conductor used in the ultra-high voltage single-circuit AC transmission line.

[0076] A second calculation unit 304 for calculating the surface potential gradient g m (m) of the mth charge point element according to the voltage U mmax of the mth phase transmission line corresponding to the mth charge point element, the maximum sag C m0 , the height H eq , and the equivalent radius r av of the multi-bundled conductor.

[0077] A third calculation unit 305 for calculating the sound power level PWL(m) of the mth charge point element according to the surface potential gradient g av (m) of the mth charge point element and the equivalent radius req Calculate the acoustic power level PWL(m) of the m-th charge point element;

[0078] The result output unit 306 is used to output the sound power level PWL(m) of the m-th charge point element and the height H. m0 And calculate the audible noise SLA of the ultra-high voltage single-circuit AC transmission line at any point in the two-dimensional plane by the perpendicular distance δ from the straight line representing the ground.

[0079] Preferably, the first calculation unit 303 calculates the equivalent radius r of the multi-split conductor based on the number of conductor splits n, the diameter d of each sub-conductor, and the diameter b of the split conductors used in the ultra-high voltage single-circuit AC transmission line. eq Among them, the equivalent radius r of the multi-split conductor eq The calculation formula is:

[0080]

[0081] In the formula, the units of d and b are mm.

[0082] Preferably, the second calculation unit 304 calculates the voltage U of the m-phase transmission line corresponding to the m-th charge point element. m and maximum sag C mmax The height H m0 And the equivalent radius r of the multi-split conductor. eq Calculate the surface potential gradient g of the m-th charge point element. av (m), its calculation formula is:

[0083]

[0084] H m1 =H m0 +C mmax / 3

[0085] In the formula, C mmax H m0 and H m1 The unit is m, g av The unit of (m) is kV / cm.

[0086] Preferably, the third calculation unit 305 calculates based on the surface potential gradient g of the m-th charge point element. av (m) and the equivalent radius r of the multi-split conductor eq The sound power level PWL(m) of the m-th charge point element is calculated using the following formula:

[0087] PWL(m) = -164.6 + 130lgg av (m)+55lgr eq .

[0088] Preferably, the result output unit 306 calculates the sound pressure level PWL(m) of the mth charge point element and the height H m0 The audible noise SLA of the EHV single-circuit AC transmission line at an arbitrary point in a two-dimensional plane is calculated according to the vertical distance δ of the line representing the ground from the point, and the formula is:

[0089]

[0090] In the formula, SLA is the A-weighted sound level, in dB.

[0091] The system for calculating the audible noise of the EHV single-circuit AC transmission line according to the present application reduces the dimension of the three-dimensional model of the EHV single-circuit AC transmission line, and the steps for calculating the audible noise of an arbitrary point in a two-dimensional plane are the same as those of the method for calculating the audible noise of the EHV single-circuit AC transmission line according to the present application, and the technical effects are also the same, which will not be described here.

[0092] The present application has been described by reference to a few embodiments. However, as known to those skilled in the art, other embodiments, which are within the scope of the present application, are equivalent to the embodiments disclosed above and are limited only by the claims accompanying the present patent.

[0093] Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a" or "an" means "at least one" unless otherwise clearly indicated by the context of the disclosure. The steps of any methods disclosed herein need not be performed in the exact order disclosed, unless explicitly stated.

[0094] Those skilled in the art will appreciate that embodiments of the present application can be devised for use with three-dimensional, two-dimensional, and / or one-dimensional systems. One skilled in the art will further appreciate that the application can be embodied as a method, data processing system, or computer program product. Accordingly, the present application can take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects all generally referred to herein as a "circuit" or "module." Furthermore, the present application can take the form of a computer program product on a data storage medium having computer-readable program code embodied in the medium.

[0095] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks. Figure 1 one or more flow or blocks.

[0096] These computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart block or blocks. Figure 1 one or more flow or blocks. Figure 1 one or more flow or blocks.

[0097] The computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks. Figure 1 one or more flow or blocks. Figure 1 one or more flow or blocks.

[0098] Finally, it should be noted that the above-mentioned embodiments are merely intended to illustrate the technical solutions of the present application, but not to limit the same. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalent replaced without departing from the spirit and scope of the present application, and any modification or equivalent replacement should be covered within the scope of protection of the claims of the present application.

Claims

1. A method of calculating audible noise of an ultrahigh voltage single circuit AC transmission line, characterized by, The method comprises: A catenary model of a super-high voltage single circuit AC transmission line is equivalent to a string of straight charge elements wherein the catenary model of a phase of the super-high voltage single circuit AC transmission line is equivalent to a string of straight charge elements wherein the catenary model of a phase of the super-high voltage single circuit AC transmission line is equivalent to a string of straight charge elements , is the number of phases of the single circuit AC transmission line The first long straight charge element in a three-dimensional environment is equivalent to the first charge point element in a two-dimensional plane, and the ground is equivalent to a straight line, wherein the height of the first charge point element from the ground The height of the lowest point of the transmission line sag from the ground; The number of sub-conductors of a multi-bundled conductor used in an extra-high voltage single circuit AC transmission line , diameter of each sub-conductor and diameter of the bundled conductor calculating the equivalent radius of the multi-bundled conductor ; According to the first charge point element corresponding to the voltage of the transmission line and the maximum sag , the height , and the equivalent radius of the multi-bundled conductor , the surface potential gradient of the first charge point element is calculated , and the calculation formula is: wherein , and in m, in kV / cm; According to the first surface potential gradient of the charge point element and the equivalent radius of the multi-split wire calculating the sound power level of the first charge point element ; According to the first sound power level of the charge point element and the height , and the perpendicular distance of the straight line representing the distance of any point in the two-dimensional plane from the ground Calculate the audible noise of the super-high voltage single-circuit AC transmission line at this point .

2. The method of claim 1, wherein, The number of sub-conductors of a multi-bundled conductor used in an ultra-high voltage single circuit AC transmission line the diameter of each sub-conductor and the diameter of the bundled conductor calculating the equivalent radius of the multi-bundled conductor wherein the equivalent radius of the multi-bundled conductor is calculated by the formula: wherein and in mm.

3. The method of claim 1, wherein, According to the first Surface potential gradient of the first Equivalent radius of the multi-split wire Calculating the sound power level of the first Charge point element The formula is: 。 4. The method of claim 1, wherein, According to the first sound power level of the charge point element and the height , and the vertical distance of the straight line representing the distance of any point in the two-dimensional plane from the ground The audible noise of the super-high voltage single-circuit AC transmission line at the point is calculated The calculation formula is: In the formula, is Sound pressure level, in dB .

5. A system for calculating audible noise of an ultrahigh voltage single circuit AC transmission line, characterized by, The system comprises: The first equivalent unit is used for equivalent of catenary model of single-circuit AC transmission line with extra-high voltage The first equivalent unit is used for equivalent of catenary model of single-circuit AC transmission line with extra-high voltage The first equivalent unit is used for equivalent of catenary model of single-circuit AC transmission line with extra-high voltage The first equivalent unit is used for equivalent of catenary model of single-circuit AC transmission line with extra-high voltage is the phase number of single-circuit AC transmission line The second equivalent unit is used for equivalent the first The length of the straight charge element to the first Charge point element in a two-dimensional plane, and the ground is equivalent to a straight line, wherein the first Charge point element is at a height of Take The height of the lowest point of the transmission line sag from the ground. a first calculation unit configured to calculate a number of sub-conductors of a multi-bundled conductor used in an ultra-high voltage single-circuit AC power transmission line a diameter of each sub-conductor and a diameter of the bundled conductor calculate an equivalent radius of the multi-bundled conductor ; The second computing unit is configured to calculate the surface potential gradient of the first charge point element according to the voltage and the maximum sag of the power transmission line corresponding to the first charge point element, the height, and the equivalent radius of the multi-bundled conductor. , the computing formula being:​​​​​​​ wherein , and in m, in kV / cm; The third calculation unit is used to calculate based on the first... Surface potential gradient of a charge point element Equivalent radius of multi-split conductors Calculate the first The sound power level of a single charge point element ; The result output unit is used to output the result based on the first... The sound power level of a single charge point element and the height And the perpendicular distance from any point in a two-dimensional plane to a straight line representing the ground. Calculate the audible noise of the ultra-high voltage single-circuit AC transmission line at this point. .

6. The system of claim 5, wherein, The first calculation unit calculates the number of sub-conductors of a multi-bundled conductor used in an extra-high voltage single-circuit AC power transmission line , a diameter of each sub-conductor , and a diameter of the bundled conductor The equivalent radius of the multi-bundled conductor is calculated wherein the equivalent radius of the multi-bundled conductor is calculated by the following formula wherein and in mm.

7. The system of claim 5, wherein, The third calculation unit calculates the surface potential gradient of the first charge point element according to the formula: and the equivalent radius of the multi-split conductor The fourth calculation unit calculates the sound power level of the first charge point element according to the formula: The fifth calculation unit calculates the sound power level of the first charge point element according to the formula:​​ 。 8. The system of claim 5, wherein, The result output unit calculates the audible noise of the super-high voltage single-circuit AC transmission line at the point according to the sound power level of the first charge point element and the height and the vertical distance of the straight line representing the distance of any point in the two-dimensional plane from the ground to the ground The calculation formula is: ​ In the formula, is Sound pressure level, in dB .

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