Flexible jumper wire raising position determination method and local hardening method

Abstract

The invention provides a soft jumper wire raising position determination method and a local hardening method, and relates to the technical field of power transmission lines, and the soft jumper wire raising position determination method comprises the steps: obtaining the three-dimensional real spot cloud data of a power transmission line strain tower and a soft jumper wire; converting the three-dimensional real scene point cloud data into a three-dimensional real scene model; determining the wind speed time history of the valley top based on the wind field characteristics of the slope wind; determining a wind load under the action of slope type wind according to the wind speed time history of the valley top; and importing the three-dimensional live-action model and the wind load into finite element simulation software for simulation, and determining the rising position of the flexible jumper wire according to a simulation result. According to the invention, the rising position of the flexible jumper can be determined, the rising deformation amount, the deformation length and the deformation position of the flexible jumper can be determined, a local hardening method of the flexible jumper is provided, a technical support is provided for the rising suppression measure of the flexible jumper, and the overall disassembly and modification of a traditional hardening device of the flexible jumper are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of power transmission lines, and in particular to a method for determining a rising position of a soft jumper and a local hardening method. Background Art

[0002] In the operation of the power system, there are many factors that affect the normal operation of the transmission line, including natural factors such as meteorological conditions and human factors such as operation and maintenance. Harsh natural conditions such as rainfall, lightning, and wind may affect the normal operation of the transmission line. In recent years, discharge flashover accidents caused by upward wind have occurred frequently, which shows that wind is an important factor affecting power supply reliability.

[0003] Under the action of wind, there are two main types of responses of transmission line conductors and jumpers: one is the wind deflection displacement of the insulator string of the straight tower and the jumper of the tension tower, and the other is the upward deformation of the jumper of the tension tower. At present, the research on the response characteristics of overhead transmission lines under the action of wind fields mainly focuses on the wind deflection of the insulator string of the straight tower, while there is little research on the upward deformation of the jumper of the tension tower, especially the research on the influence of special terrain conditions such as canyon wind and slope wind on the upward deformation of the jumper is almost blank. Summary of the invention

[0004] The purpose of the present invention is to provide a method for determining the upward position of a soft jumper and a local hardening method, which are used to solve the problems that there are few studies on the upward movement of jumpers in the prior art, the upward position of soft jumpers under the action of slope-type winds is unclear, and there is a lack of corresponding suppression measures. The method can determine the upward position of soft jumpers under the action of slope-type winds and provide technical support for the suppression measures for the upward movement of soft jumpers.

[0005] In order to achieve the above object, in a first aspect, the present invention provides a method for determining a rising position of a soft jumper, comprising: Obtain 3D real-time cloud data of transmission line tension towers and soft jumpers; Convert 3D real scene cloud data into 3D real scene model; Based on the wind field characteristics of slope wind, determine the wind speed time history at the top of the valley; Determine the wind load under slope wind action based on the wind speed time history at the top of the valley; The three-dimensional real-scene model and wind load are imported into the finite element simulation software and simulated, and the upward position of the soft jumper is determined according to the simulation results.

[0006] According to a method for determining the upward position of a soft jumper provided by the present invention, the wind field characteristics of the slope wind include: air humidity, temperature difference between the top and bottom of the valley, valley slope, and atmospheric pressure.

[0007] According to a method for determining the upward position of a soft jumper provided by the present invention, the expression of the wind speed time history at the valley top is:

[0008] in,

[0009]

[0010]

[0011] In the formula, represents the wind speed time history at the top of the valley; represents the wind speed time history at the valley bottom; Indicates the temperature of the valley floor; Indicates the temperature at the top of the valley; It indicates the temperature difference between the top and bottom of the valley; The adjustment factor that represents the effect of temperature difference on wind speed; It represents the average temperature of the valley top and valley bottom; Indicates the slope angle of the valley bottom; Indicates the slope angle of the valley top; An adjustment factor representing the effect of humidity on wind speed; It indicates the specific humidity of the valley bottom; It indicates the specific humidity at the valley top; is the adjustment factor for the effect of pressure difference on wind speed; Indicates the atmospheric pressure at the bottom of the valley; It indicates the atmospheric pressure at the top of the valley; It indicates the difference in air pressure between the bottom and top of the valley; is standard atmospheric pressure.

[0012] According to a method for determining a rising position of a soft jumper provided by the present invention, the rising position of the soft jumper includes an rising deformation amount, a deformation length, and a deformation position of the soft jumper.

[0013] According to a method for determining the rising position of a soft jumper provided by the present invention, a three-dimensional real scene model and wind load are imported into finite element simulation software and simulated, and the rising position of the soft jumper is determined according to the simulation results, including: The three-dimensional real-scene model and wind load are imported into the finite element simulation software, and simulation calculations of the three-dimensional real-scene model are carried out under two working conditions: horizontal rightward and horizontal leftward, to determine the upward deformation amount, deformation length and deformation position of the left and right parts of the soft jumper.

[0014] In a second aspect, the present invention provides a method for local hardening of a soft jumper, comprising: The method for determining the rising position of the soft jumper of the first aspect is adopted to determine the rising position of the soft jumper, and the local hardening length and hardening position of the soft jumper are determined according to the rising position of the soft jumper. A local hardening device is installed based on the local hardening length and hardening position of the soft jumper to suppress the rising of the soft jumper.

[0015] According to a method for local hardening of a soft jumper provided by the present invention, the local hardening device includes a damping member, two wire clamps, a fastener, and a support rod. The two wire clamps are respectively connected to the two ends of the support rod through fasteners. The wire clamp is provided with a wire hole. The damping member is arranged in the wire hole. The soft jumper passes through the wire hole, and the damping member is used to realize a fixed connection between the soft jumper and the wire clamp.

[0016] According to a method for local hardening of a soft jumper provided by the present invention, the damping member is made of rubber, and the support rod is made of aluminum alloy.

[0017] According to a method for local hardening of a soft jumper provided by the present invention, the transmission line is a 500kV overhead transmission line.

[0018] According to a method for local hardening of a soft jumper provided by the present invention, there are two local hardening devices, and the transmission line includes four soft jumpers; one local hardening device connects two soft jumpers, and another local hardening device connects the other two soft jumpers; the support rods of the two local hardening devices are cross-arranged.

[0019] The technical solution of the present invention has at least the following technical effects: The present invention provides a method for determining the rising position of a soft jumper and a local hardening method, the method for determining the rising position of a soft jumper includes: obtaining three-dimensional real-life cloud data of a transmission line tension tower and a soft jumper; converting the three-dimensional real-life cloud data into a three-dimensional real-scene model; determining the wind speed time series of the valley top based on the wind field characteristics of the slope-type wind; determining the wind load under the action of the slope-type wind according to the wind speed time series of the valley top; importing the three-dimensional real-scene model and the wind load into finite element simulation software and performing simulation, and determining the rising position of the soft jumper according to the simulation results. The present invention can determine the rising position of the soft jumper, including the deformation amount, deformation length, and deformation position of the soft jumper, and proposes a local hardening method for the soft jumper, providing technical support for the soft jumper rising suppression measures, and avoiding the overall disassembly and modification of the traditional soft jumper hardening device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] In the attached picture: Figure 1 It is a flow chart of the method for determining the rising position of the soft jumper of the present invention; Figure 2 It is a structural schematic diagram of the local hardening device of the present invention; Figure 3It is a schematic diagram of the local hardening device of the present invention installed on the soft jumper of the transmission line.

[0022] Reference numerals: 1. Damping element; 2. Two-wire clamp; 3. Fastener; 4. Support rod; 100. Local hardening device; 200. Soft jumper. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Some embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0025] When the tension tower jumper is affected by wind on a hillside and in flat terrain, its upward movement is very different. This is because slope wind is generated in special landforms such as valleys, and its wind field characteristics are affected by many factors such as topography, air humidity, temperature difference between the top and bottom of the valley, and air pressure difference between the top and bottom of the valley.

[0026] See also Figure 1 The embodiment of the present invention provides a method for determining the rising position of a jumper, which can be applied to determine the rising position of a 500kV soft jumper under the action of slope wind. The method comprises: S1. Obtaining 3D real-time cloud data of transmission line tension towers and jumpers; Specifically, laser radar equipment can be used to scan the transmission line tension towers and jumpers to obtain three-dimensional real-time point cloud data of the transmission line tension towers and jumpers.

[0027] S2, converting the 3D real scene cloud data into a 3D real scene model; S3. Determine the wind speed time history at the top of the valley based on the wind field characteristics of the slope wind; Specifically, the wind field characteristics of slope wind include: air humidity, temperature difference between the top and bottom of the valley, valley slope, and atmospheric pressure. The study of the wind field characteristics of slope wind can be divided into the following steps: S3.1. Calculate the effect of the temperature difference between the valley bottom and the valley top on the wind speed of the slope wind. The effect of the temperature difference on the wind speed can be calculated using the following formula:

[0028]

[0029]

[0030] In the formula, represents the wind speed time history at the top of the valley (i.e., the relationship between wind speed and time t); Indicates the wind speed history at the bottom of the valley, i.e. the design wind speed of the tension tower The pulsating wind speed time history under the Indicates the temperature of the valley floor; Indicates the temperature at the top of the valley; It indicates the temperature difference between the top and bottom of the valley; It represents the average temperature of the valley top and valley bottom; It is the adjustment factor for the temperature difference, which is determined based on the experimental data under the corresponding environment.

[0031] S3.2. Calculate the impact of valley terrain and slope on slope wind speed. When the wind blows from the bottom of the valley to the top of the valley, the wind speed will change due to factors such as terrain slope. The following formula can be used for calculation:

[0032]

[0033] In the formula, k is the adjustment factor for wind speed changes due to slope changes; is the slope angle of the canyon bottom (i.e. the angle between the wind speed direction at the bottom of the valley and the horizontal plane); It is the slope angle of the canyon top (i.e. the angle between the wind and the horizontal plane before it approaches the valley top).

[0034] S3.3. Calculate the effect of air humidity on slope wind speed. The effect of air humidity on wind speed can be calculated using the following formula:

[0035] In the formula, It is the adjustment factor of the effect of humidity on wind speed, which is determined based on experimental data under the corresponding environment; It is the specific humidity in the canyon, which refers to the mass of water vapor contained in a unit mass of air; is the specific humidity of the valley bottom; The specific humidity at the top of the valley. The specific humidity can usually be calculated by the following formula:

[0036] In the formula, is the mass of water vapor; is the mass of dry air.

[0037] S3.4. The effect of atmospheric pressure on wind speed can be calculated using the following formula:

[0038]

[0039] In the formula, It is the adjustment factor of the effect of air pressure difference on wind speed, which is determined based on experimental data under the corresponding environment; is the atmospheric pressure at the bottom of the valley; is the atmospheric pressure at the top of the valley; It is the difference in air pressure between the valley bottom and the valley top; is standard atmospheric pressure.

[0040] S3.5. The calculation method for determining the wind speed at the top of the valley is based on factors such as temperature difference, valley slope, air humidity, and atmospheric pressure. It can be expressed by the following formula:

[0041] S4. Determine the wind load under the action of slope wind according to the wind speed time history at the top of the valley; S5. Import the three-dimensional real-scene model and wind load into the finite element simulation software and perform simulation, and determine the upward position of the soft jumper according to the simulation results.

[0042] Specifically, the rising position of the soft jumper includes the rising deformation amount, deformation length, and deformation position of the soft jumper.

[0043] The corresponding wind load parameters are set on the finite element simulation software, and simulation calculations are performed taking the gravity field into consideration. The uplift deformation, deformation length, and deformation position of the soft jumper of the tension tower are determined based on the simulation results.

[0044] In some embodiments, S5 specifically includes: importing the three-dimensional real-scene model and wind load into finite element simulation software, performing simulation calculations of the three-dimensional real-scene model under two working conditions: horizontal to the right and horizontal to the left, and determining the upward deformation amount, deformation length, and deformation position of the left and right parts of the soft jumper.

[0045] Another embodiment of the present invention provides a method for local hardening of a soft jumper, comprising: using the method for determining the rising position of the soft jumper of the aforementioned embodiment to determine the rising position of the soft jumper, determining the local hardening length and hardening location of the soft jumper according to the rising position of the soft jumper, and installing a local hardening device based on the local hardening length and hardening location of the soft jumper to suppress the rising of the soft jumper.

[0046] It should be noted that the soft jumper will rise under the action of wind, which may cause discharge tripping. The present invention installs a local hardening device at the rising position of the jumper, which can achieve local hardening of the soft jumper to suppress the rising of the soft jumper, thereby avoiding disassembly and modification of the entire soft jumper.

[0047] Specifically, Figure 2As shown, the local hardening device includes a damping member 1, two wire clamps 2, a fastener 3, and a support rod 4. The two wire clamps 2 are respectively connected to the two ends of the support rod 4 through the fasteners 3. The wire clamps 2 are provided with wire holes. The damping member 1 is arranged in the wire holes. The soft jumper wire passes through the wire holes, and the soft jumper wire and the wire clamp 2 are fixedly connected through the damping member 1.

[0048] The damping member 1 is made of rubber and has the functions of buffering and vibration prevention. It is used to reduce the friction loss between the wire clamp 2 and the soft jumper and prevent vibration. The wire clamp 2 is provided with a first connection hole and a wire hole. The damping member 1 is embedded in the wire hole. The soft jumper passes through the wire hole of the wire clamp 2. The size of the wire hole can match the soft jumpers of different diameters and can ensure a certain grip. The fastener 3 is used to connect and fix the wire clamp 2 and the support rod 4. The two ends of the support rod 4 are provided with a second connection hole. The fastener 3 passes through the first connection hole and the second connection hole and cross-fixes the support rod 4 to the wire clamp 2. The material of the support rod 4 is aluminum alloy. The aperture size of the second connection hole is consistent with that of the first connection hole. The support rod 4 of a certain length is fixed to the wire clamp 2 by the fastener 3. The length of the support rod 4 is determined by the local hardening length of the soft jumper.

[0049] Specifically, the transmission line is a 500kV overhead transmission line. Figure 3 As shown, there are two local hardening devices 100, and the transmission line includes four flexible jumpers 200; one local hardening device 100 connects two flexible jumpers 200, and another local hardening device 100 connects the other two flexible jumpers 200; the support rods 4 of the two local hardening devices 100 are cross-arranged.

[0050] In summary, the method for determining the rising position of the soft jumper and the local hardening method provided by the present invention can be applied to the determination of the rising position of the soft jumper and the local hardening measures of the 500kV overhead transmission line. In view of the effect of the wind field under the valley terrain, the influence of factors such as the canyon slope, the temperature difference between the top and the bottom of the valley, the air humidity, and the pressure difference between the top and the bottom of the valley on the wind field are considered. Based on the three-dimensional real-life model of the soft jumper of the 500kV tension tower under special terrain, the finite element simulation calculation is used to determine the rising deformation amount, deformation length, and deformation position of the soft jumper of the 500kV tension tower, and a local hardening method for the soft jumper is proposed to provide technical support for the soft jumper rising suppression measures. Local hardening of the soft jumper can be achieved to suppress the rise of the jumper. The local hardening length and hardening position are determined based on the simulation calculation of the three-dimensional real-life model, and a local hardening device is installed for the position, which can effectively suppress the rise of the soft jumper and avoid the overall disassembly and modification of the traditional soft jumper hardening device.

[0051] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the embodiments disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for determining the rising position of a soft jumper, characterized in that: include: Obtain 3D real-time cloud data of transmission line tension towers and soft jumpers; Converting the three-dimensional real scene point cloud data into a three-dimensional real scene model; Based on the wind field characteristics of slope wind, determine the wind speed time history at the top of the valley; Determine the wind load under the slope wind action according to the wind speed time history at the valley top; The three-dimensional real-scene model and the wind load are introduced into finite element simulation software and simulated, and the upward position of the soft jumper is determined according to the simulation results.

2. The method for determining the upward position of a soft jumper according to claim 1, characterized in that: The wind field characteristics of the slope wind include: air humidity, temperature difference between the valley top and valley bottom, valley slope, and atmospheric pressure.

3. The method for determining the upward position of a soft jumper according to claim 2, characterized in that: The expression of the wind speed time history at the valley top is: in, In the formula, represents the wind speed time history at the top of the valley; represents the wind speed time history at the valley bottom; Indicates the temperature of the valley floor; Indicates the temperature at the top of the valley; It indicates the temperature difference between the top and bottom of the valley; An adjustment factor that represents the effect of temperature difference on wind speed; It represents the average temperature of the valley top and valley bottom; Indicates the slope angle of the valley bottom; Indicates the slope angle of the valley top; An adjustment factor that represents the effect of humidity on wind speed; It indicates the specific humidity of the valley bottom; It indicates the specific humidity at the valley top; is the adjustment factor for the effect of pressure difference on wind speed; Indicates the atmospheric pressure at the bottom of the valley; It indicates the atmospheric pressure at the top of the valley; It indicates the difference in air pressure between the bottom and top of the valley; is standard atmospheric pressure.

4. The method for determining the upward position of a soft jumper according to claim 1, characterized in that: The rising position of the soft jumper includes the rising deformation amount, deformation length and deformation position of the soft jumper.

5. The method for determining the upward position of a soft jumper according to claim 4, characterized in that: The step of importing the three-dimensional real scene model and the wind load into finite element simulation software and performing simulation, and determining the upward position of the soft jumper according to the simulation result, comprises: The three-dimensional real-scene model and the wind load are imported into the finite element simulation software, and simulation calculations of the three-dimensional real-scene model are performed under two working conditions: horizontal rightward and horizontal leftward, to determine the upward deformation amount, deformation length, and deformation position of the left and right parts of the soft jumper.

6. A method for local hardening of a soft jumper, characterized in that: include: The method for determining the rising position of the soft jumper as described in any one of claims 1 to 5 is used to determine the rising position of the soft jumper, and the local hardening length and hardening position of the soft jumper are determined according to the rising position of the soft jumper. A local hardening device is installed based on the local hardening length and hardening position of the soft jumper to suppress the rising of the soft jumper.

7. The method for local hardening of a soft jumper according to claim 6, characterized in that: The local hardening device includes a damping member, two wire clamps, a fastener, and a support rod. The two wire clamps are respectively connected to the two ends of the support rod through the fasteners. The wire clamp is provided with a wire hole. The damping member is arranged in the wire hole. The soft jumper wire passes through the wire hole, and the soft jumper wire and the wire clamp are fixedly connected through the damping member.

8. The method for local hardening of a soft jumper according to claim 7, characterized in that: The damping element is made of rubber, and the support rod is made of aluminum alloy.

9. The method for local hardening of a soft jumper according to claim 7, characterized in that: The transmission line is a 500kV overhead transmission line.

10. The method for local hardening of a soft jumper according to claim 9, characterized in that: The number of the local hardening devices is two, and the power transmission line includes four soft jumpers; one local hardening device is connected to two soft jumpers, and the other local hardening device is connected to the other two soft jumpers; the support rods of the two local hardening devices are cross-arranged.

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