An overhead line limit height difference coefficient calculation method based on relative sag coefficient method

Abstract

The application relates to an overhead line limit height difference coefficient calculation method based on a relative sag coefficient method, and comprises the following steps: obtaining target data; defining 0.445 as an absolute sag coefficient, and defining the product of the overhead line semi-curvature k at the sag lowest point and the span L as an intrinsic sag coefficient; constructing a limit height difference coefficient calculation formula: wherein k is the overhead line semi-curvature at the sag lowest point, 0.445 is the absolute sag coefficient corresponding to the minimum curvature at the overhead line suspension point, kL is the intrinsic sag coefficient, L is the span, h is the height difference, and p is the limit height difference coefficient; and the limit height difference coefficient is calculated based on the target data and the limit height difference coefficient calculation formula.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of based on relative sag coefficient method overhead line limit height difference coefficient calculation method, belong to electric power facilities parameter calculation technical field. BACKGROUND

[0002] Overhead transmission line specification stipulates that the maximum use stress of suspension point is not more than 1.1 times of the horizontal stress of sag minimum point, which is set to ensure that the stress of conductor suspension point under the annual average temperature does not exceed 22.5%, especially in the line of large mountainous area, due to the large height difference angle (its tangent value is defined as the ratio of suspension point height difference to span), which often exceeds this limit value. When designing the line, the suspension point stress is generally checked by the suspension point stress curve, but the original formula given by the design manual is too complex, which contains transcendental function, so that the program design iteration is difficult, and it is not convenient for engineering application. SUMMARY

[0003] In order to solve the problems existing in the prior art, the present application proposes an overhead line limit height difference coefficient calculation method based on relative sag coefficient method, which directly obtains the relationship between suspension point stress and curvature from the perspective of minimum curvature requirement, so as to be used for calculating limit height difference coefficient (also known as maximum allowable height difference coefficient).

[0004] The technical scheme of the present application is as follows:

[0005] In the first aspect, the present application proposes an overhead line limit height difference coefficient calculation method based on relative sag coefficient method, comprising the following steps:

[0006] Obtaining target data, including span L of target overhead line, ratio load corresponding to maximum load working condition And maximum use stress ;

[0007] Defining 0.445 as the absolute sag coefficient corresponding to the minimum curvature at the suspension point of overhead line, and defining the product of the half curvature of overhead line at sag minimum point and span L as eigenvalue sag coefficient;

[0008] Constructing limit height difference coefficient calculation formula based on the absolute sag coefficient and eigenvalue sag coefficient:

[0009] ;

[0010] Wherein, is the half curvature of overhead line at sag minimum point, is the absolute sag coefficient corresponding to the minimum curvature at the suspension point of overhead line, is eigenvalue sag coefficient, L is span, is limit height difference coefficient;​

[0011] The limit sag coefficient is calculated based on the target data and the limit sag coefficient calculation formula.

[0012] In a second aspect, the present application provides an overhead line limit sag coefficient calculation system based on the relative sag coefficient method, comprising:

[0013] The parameter acquisition module is configured to acquire target data, including the span L of the target overhead line, the specific load of the maximum load working condition and the maximum use stress

[0014] The parameter definition module is configured to define 0.445 as the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, and define the overhead line half curvature at the sag lowest point The product of the span L is the intrinsic sag coefficient.

[0015] The formula construction module is configured to construct a limit sag coefficient calculation formula based on the absolute sag coefficient and the intrinsic sag coefficient:

[0016] ;

[0017] Wherein, is the overhead line half curvature at the sag lowest point, is the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, is the intrinsic sag coefficient, and L is the span, is the limit sag coefficient.

[0018] The calculation module is configured to calculate the limit sag coefficient based on the target data and the limit sag coefficient calculation formula.

[0019] In a third aspect, the present application provides an electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to realize the overhead line limit sag coefficient calculation method based on the relative sag coefficient method according to any one of the embodiments of the present application.

[0020] In a fourth aspect, the present application provides a computer readable storage medium having a computer program stored thereon, wherein the program is executed by a processor to realize the overhead line limit sag coefficient calculation method based on the relative sag coefficient method according to any one of the embodiments of the present application.

[0021] In a fifth aspect, the present application provides an overhead line suspension point stress verification method based on the overhead line limit sag coefficient, comprising the following steps:

[0022] The limit sag coefficient calculation method based on the relative sag coefficient method is used to calculate a plurality of limit sag coefficients Data about the change of the span L;

[0023] Based on the limit sag coefficient Data about the change of the span L is plotted in a rectangular coordinate system The -L curve;

[0024] The stress checking unit calculates the allowable sag coefficient of the target overhead line suspension point, takes the lower part of the -L curve as a safety area, and judges whether the allowable sag coefficient of the target overhead line suspension point is in the safety area to complete stress checking. The stress checking unit calculates the allowable sag coefficient of the target overhead line suspension point, takes the lower part of the -L curve as a safety area, and judges whether the allowable sag coefficient of the target overhead line suspension point is in the safety area to complete stress checking.

[0025] In a sixth aspect, the present application provides an overhead line suspension point stress checking system based on an overhead line limit sag coefficient, comprising:

[0026] The drawing data acquisition unit is used to calculate a plurality of limit sag coefficients by using the limit sag coefficient calculation method based on the relative sag coefficient method. Data about the change of the span L;

[0027] The curve plotting unit is used to plot the limit sag coefficient Data about the change of the span L is plotted in a rectangular coordinate system The -L curve;

[0028] The stress checking unit calculates the allowable sag coefficient of the target overhead line suspension point, takes the lower part of the -L curve as a safety area, and judges whether the allowable sag coefficient of the target overhead line suspension point is in the safety area to complete stress checking. The stress checking unit calculates the allowable sag coefficient of the target overhead line suspension point, takes the lower part of the -L curve as a safety area, and judges whether the allowable sag coefficient of the target overhead line suspension point is in the safety area to complete stress checking.

[0029] In a seventh aspect, the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to realize the overhead line suspension point stress checking method based on an overhead line limit sag coefficient.

[0030] In an eighth aspect, the present application provides a computer readable storage medium, which stores a computer program, wherein the program is executed by a processor to realize the overhead line suspension point stress checking method based on an overhead line limit sag coefficient.

[0031] The present application has the following advantages:

[0032] 1. The overhead line limit height difference coefficient calculation method based on the relative sag coefficient method, in the case of known given parameters, the constant of the absolute sag coefficient 0.445 corresponding to the minimum curvature is used to simplify the formula into a physical model that can be understood by designers, the mathematical model is simple, whether manual calculation or using electronic spreadsheets is very convenient, and the application effect is very significant.

[0033] 2. The overhead line suspension point stress verification method based on the overhead line limit height difference coefficient is also proposed, a plurality of limit height difference coefficients are obtained by calculation The data about the span L is changed, and then -L curve is drawn, and stress verification is carried out through the -L curve, so that whether the overhead line suspension point meets the requirements can be quickly judged. DETAILED DESCRIPTION

[0034] Figure 1 The method flowchart of the first embodiment of the present application is shown in the figure;

[0035] Figure 2 The method flowchart of the fifth embodiment of the present application is shown in the figure;

[0036] Figure 3 The example diagram of the -L curve drawn in the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0038] It should be understood that the step numbers used herein are only for the convenience of description, and are not limited to the execution sequence of the steps.

[0039] It should be understood that the terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification and the appended claims, unless otherwise clear from the context, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0040] The terms "include" and "contain" indicate the presence of the described features, whole, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, whole, steps, operations, elements, components and / or sets thereof.

[0041] The term "and / or" means any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

[0042] Embodiment one:

[0043] Referring to Figure 1 , the embodiment proposes a relative sag coefficient method-based overhead line limit height difference coefficient calculation method, including the following steps:

[0044] S101, target data is acquired, including the span L of the target overhead line, the specific load corresponding to the maximum load working condition , and the maximum use stress ;

[0045] S102, 0.445 is defined as the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, and the overhead line half-curvature at the sag lowest point is defined , and the product of the overhead line half-curvature at the sag lowest point and the span L is the intrinsic sag coefficient, wherein the overhead line half-curvature at the sag lowest point refers to one half (that is, half) of the overhead line curvature at the sag lowest point;

[0046] S103, a limit height difference coefficient calculation formula based on the absolute sag coefficient and the intrinsic sag coefficient is constructed:

[0047] (Formula 1)

[0048] In formula 1, L is the span, with the unit of m;

[0049] 0.445 is the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, (note that it is 0 at the sag lowest point);

[0050] is half of the maximum curvature under the maximum load state, with the unit of 1 / m, that is, the overhead line half-curvature at the sag lowest point;

[0051] is half of the product of the maximum curvature under the maximum load state and the span, which is a dimensionless coefficient, and is called the intrinsic sag coefficient in the application;

[0052] is the specific load corresponding to the maximum load working condition, with the unit of N / (m.mm 2 );

[0053] is the limit height difference coefficient, which is dimensionless.

[0054] is the relative sag (difference) coefficient f of the absolute sag coefficient and the intrinsic sag coefficient;

[0055] Relative increase coefficient of conductor elastic potential energy caused by relative sag coefficient f;

[0056] In the embodiment, the energy storage conversion coefficient corresponding to the intrinsic sag coefficient is defined.

[0057] In S104, the limit height difference coefficient is calculated based on the target data and the limit height difference coefficient calculation formula.

[0058] In the prior art, the original formula for calculating the limit height difference coefficient is too complex and contains transcendental functions, making the program design iteration difficult. The method proposed in the embodiment is based on this shortcoming and gives an elementary function expression without iterative calculation to calculate the limit height difference coefficient under the maximum load.

[0059] According to the measurement, the maximum error of the method proposed in the embodiment is not more than 0.2%, which can be basically ignored when the height difference is calculated in meters as an engineering unit, because the error is smaller than the allowable error caused by the stringing process.

[0060] Based on the above embodiment, the absolute sag coefficient 0.445 corresponding to the minimum curvature at the suspension point of the overhead line is given, and a polynomial formula is derived by simplifying the calculation with this coefficient. This coefficient is applicable to all overhead lines with a conductor safety factor of 2.5-3.5. The dimensionless (maximum curvature under maximum load condition multiplied by half of the span, intrinsic sag coefficient) is used as a variable to calculate the limit height difference coefficient. Since it is a dimensionless coefficient, the height difference coefficient is also a dimensionless coefficient. Such a formula is more practical for general curve design. When the span is 500m, the value of this is about 0.14-0.19.

[0061] To prove the effectiveness and superiority of the calculation method proposed in the embodiment, a specific application example is provided as follows:

[0062] A certain line, the design icing condition of a certain heavy icing area is the maximum load condition, the corresponding specific load is 0.0672 N / (m.mm 2 ), the maximum horizontal stress of the wire is 92MPa, the span L is 200m, and the limit height difference coefficient is calculated:

[0063] According to formula (1), we have:

[0064]

[0065] The calculation result is =0.3806. It can be seen that the method proposed in the embodiment adopts a relatively simple formula, and is particularly easy to realize rapid calculation through a spreadsheet or a common calculator, and is also applicable to computer program design.

[0066] The method of the application simplifies the formula to a physical model that can be understood by designers by using the constant of the absolute sag coefficient 0.445 corresponding to the minimum curvature under the condition that given parameters are known, and the main formula is (formula 1). The mathematical model is simple, and is very convenient for manual calculation or calculation using a spreadsheet, and thus the application effect is very significant.

[0067] Embodiment two:

[0068] The embodiment proposes an overhead line limit height difference coefficient calculation system based on a relative sag coefficient method, comprising:

[0069] A parameter acquisition module is configured to acquire target data, including the span L of the target overhead line, the specific load of the maximum load working condition , and the maximum use stress . The module is configured to realize the function of step S101 in the above embodiment one, and thus will not be described here again.

[0070] A parameter definition module is configured to define 0.445 as the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, and define the product of the overhead line half curvature at the sag lowest point and the span L as the intrinsic sag coefficient. The module is configured to realize the function of step S102 in the above embodiment one, and thus will not be described here again. A formula construction module is configured to construct a limit height difference coefficient calculation formula based on the absolute sag coefficient and the intrinsic sag coefficient:

[0071]

[0072]

[0073] wherein, is the overhead line half curvature at the sag lowest point, is the absolute sag coefficient corresponding to the minimum curvature at the suspension point of the overhead line, is the intrinsic sag coefficient, and L is the span, is the limit height difference coefficient. The module is configured to realize the function of step S103 in the above embodiment one, and thus will not be described here again.

[0074] A calculation module is configured to calculate the limit height difference coefficient based on the target data and the limit height difference coefficient calculation formula. The module is configured to realize the function of step S104 in the above embodiment one, and thus will not be described here again.

[0075] Embodiment three:

[0076] ​​The embodiment provides an electronic device, including a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor implements the relative sag coefficient method-based overhead line limit height difference coefficient calculation method according to any embodiment of the present application when executing the program.

[0077] Embodiment four:

[0078] The embodiment provides a computer readable storage medium, and a computer program is stored in the computer readable storage medium, and the program is executed by a processor to implement the relative sag coefficient method-based overhead line limit height difference coefficient calculation method according to any embodiment of the present application.

[0079] Embodiment five:

[0080] Referring to Figure 2 , the embodiment provides an overhead line suspension point stress checking method based on an overhead line limit height difference coefficient, and the method includes the following steps.

[0081] S201, a relative sag coefficient method-based overhead line limit height difference coefficient calculation method according to any embodiment of the present application is used to calculate and obtain a plurality of limit height difference coefficients Data about the change of the span L; engineering can be calculated according to an actual span range, and the range of 200m-1000m can be used to calculate when designing a general curve.

[0082] S202, the limit height difference coefficient Data about the change of the span L is plotted in a rectangular coordinate system by using an x-y scatter plot function of an electronic spreadsheet -L curve.

[0083] S203, an allowed height difference coefficient of a target overhead line suspension point is calculated, and the allowed height difference coefficient = L / L, is a height difference, and L is a span; the lower part of the -L curve is used as a safety area, and whether the allowed height difference coefficient of the target overhead line suspension point is in the safety area is judged to complete stress checking.

[0084] To help the person skilled in the art further understand the technical scheme of the embodiment, the following is described through a specific example.

[0085] It is known that a design icing condition of a heavy icing area is a maximum load condition, a corresponding specific load is 0.0672 N / (m.mm 2 ), a maximum value of a wire horizontal stress is 92MPa, a general engineering span range is between 200m and 1000m, so an electronic spreadsheet is used to calculate and obtain a plurality of limit height difference coefficients Data about the change of the span L are shown in Table 1.

[0086] Table 1 Limiting height difference angle curve data under icing control

[0087]

[0088] According to Table 1, the suspension point stress curve is drawn as shown in the following table. Figure 3

[0089] The present gear distance is 400m, and the height difference is 150m. The method for judging whether the stress of the suspension point exceeds the limit is as follows: the height difference coefficient of the suspension point is calculated as 150 / 400=0.375, and the curve is checked. Figure 2 The limiting height difference coefficient corresponding to the gear distance of 400m is about 0.3036, so the height difference coefficient 0.375 is not in the safe region, and therefore the stress of the gear height suspension point exceeds the limit value, and certain measures should be taken in engineering.

[0090] Further, a plurality of limiting height difference coefficients Regarding the data table of the change of the gear distance L, the limiting height difference coefficient and the linear relationship of the gear distance L are fitted according to the least square method, the formula is further simplified, and is provided for engineering design and checking personnel; in the above embodiment, the linear formula fitted according to the data in Table 1 is as follows: =(-0.000375*L+0.45415).

[0091] Embodiment six:

[0092] The present application provides an overhead line suspension point stress checking system based on the limiting height difference coefficient of overhead line, comprising:

[0093] A drawing data acquisition unit is used to calculate and acquire a plurality of limiting height difference coefficients about the change of the gear distance L by the overhead line limiting height difference coefficient calculation method based on the relative sag coefficient method according to any one of the embodiments of the present application; this module is used to realize the function of step S201 in the above embodiment five, and will not be repeated here.

[0094] A curve drawing unit is used to draw -L curve in the rectangular coordinate system based on the limiting height difference coefficient about the change of the gear distance L; this module is used to realize the function of step S202 in the above embodiment five, and will not be repeated here.

[0095] A stress checking unit is used to calculate the allowable height difference coefficient of the target overhead line suspension point, and the stress of the target overhead line suspension point is checked according to the ​The lower part of the L curve is as a safety region, and whether the allowable height difference coefficient of the overhead line suspension point is in the safety region is determined to complete stress checking; the module is used for realizing the function of step S203 in the fifth embodiment, and details are not described herein.

[0096] Embodiment seven:

[0097] The embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor realizes the overhead line suspension point stress checking method based on the limit height difference coefficient of an overhead line when executing the program.

[0098] Embodiment eight:

[0099] The embodiment provides a computer readable storage medium, and a computer program is stored in the computer readable storage medium, and the computer program is executable on the processor, and the processor realizes the overhead line suspension point stress checking method based on the limit height difference coefficient of an overhead line when executing the program.

[0100] In the embodiments of the present application, "at least one" refers to one or more, and "multiple" refers to two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which means that A exists alone, A and B exist together, and B exists alone. Wherein A and B can be singular or plural. The character " / " generally represents that the front and rear associated objects are in an "or" relationship. "At least one of the following" and the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b, and c can be single or multiple.

[0101] Those skilled in the art can realize that the units and algorithm steps described in the embodiments disclosed in the present application can be realized by electronic hardware, computer software and combination of electronic hardware and computer software. Whether the functions are realized by hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0102] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, and details are not described herein.

[0103] In several embodiments provided in the present application, any function, if realized in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application or the parts of the technical solutions that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various media that can store program codes.

[0104] The above description is only some embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, based on the content of the specification and drawings of the present application, are also included in the patent protection scope of the present application.

Claims

1. A method for calculating the maximum height difference coefficient of overhead lines based on the relative sag coefficient method, characterized in that: The following steps are involved: Obtain target data, including target overhead line span L and specific load corresponding to the maximum load condition and maximum operating stress ; Define 0.445 as the absolute sag coefficient corresponding to the minimum curvature at the overhead line suspension point, and define the half curvature of the overhead line at the lowest point of the sag The product of the span L is the intrinsic sag coefficient; The calculation formula of the limit height difference coefficient based on the absolute sag coefficient and the intrinsic sag coefficient is constructed as follows: ； in, is the half curvature of the overhead line at the lowest point of sag, is the absolute sag coefficient corresponding to the minimum curvature at the overhead line suspension point, is the intrinsic sag coefficient, L is the span, is the maximum height difference coefficient; The limit height difference coefficient is calculated based on the target data and the limit height difference coefficient calculation formula.

2. A system for calculating the maximum height difference coefficient of overhead lines based on the relative sag coefficient method, characterized in that: include: Parameter acquisition module, used to obtain target data, including the target overhead line span L, the specific load corresponding to the maximum load condition and maximum operating stress ; Parameter definition module, used to define 0.445 as the absolute sag coefficient corresponding to the minimum curvature at the overhead line suspension point, and define the half curvature of the overhead line at the lowest point of the sag The product of the span L is the intrinsic sag coefficient; A formula construction module is used to construct a calculation formula for the limit height difference coefficient based on the absolute sag coefficient and the intrinsic sag coefficient: ； in, is the half curvature of the overhead line at the lowest point of sag, is the absolute sag coefficient corresponding to the minimum curvature at the overhead line suspension point, is the intrinsic sag coefficient, L is the span, is the maximum height difference coefficient; The calculation module calculates the maximum height difference coefficient based on the target data and the maximum height difference coefficient calculation formula.

3. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the method for calculating the overhead line limit height difference coefficient based on the relative sag coefficient method as claimed in claim 1 is implemented.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for calculating the maximum height difference coefficient of an overhead line based on the relative sag coefficient method as claimed in claim 1 is implemented.

5. A method for checking stress of overhead line suspension points based on the overhead line limit height difference coefficient, characterized in that: The following steps are involved: Based on the calculation method of the overhead line limit height difference coefficient based on the relative sag coefficient method described in claim 1, several limit height difference coefficients are calculated and obtained Data on the change of gear distance L; Based on the above limit height difference coefficient The data on the change of gear distance L is plotted in the rectangular coordinate system -L curve; Calculate the allowable height difference coefficient of the target overhead line suspension point, using the The area below the -L curve is used as the safety area to determine whether the allowable height difference coefficient of the target overhead line suspension point is in the safety area to complete stress verification.

6. An overhead line suspension point stress calibration system based on the overhead line limit height difference coefficient, characterized in that: include: A drawing data acquisition unit for calculating and acquiring a plurality of limit height difference coefficients by using the overhead line limit height difference coefficient calculation method based on the relative sag coefficient method according to claim 1 Data on the change of gear distance L; Curve drawing unit, used to draw the curve based on the above limit height difference coefficient The data on the change of gear distance L is plotted in the rectangular coordinate system -L curve; Stress verification unit calculates the allowable height difference coefficient of the target overhead line suspension point, based on the The area below the -L curve is used as the safety area to determine whether the allowable height difference coefficient of the target overhead line suspension point is in the safety area to complete stress verification.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the overhead line suspension point stress calibration method based on the overhead line limit height difference coefficient as described in claim 5 is implemented.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for verifying the stress of the overhead line suspension point based on the overhead line limit height difference coefficient as described in claim 5 is implemented.

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