Overhead line icing monitoring method, device and storage medium

Abstract

The present invention provides an overhead line icing monitoring method, device and storage medium, the method comprising: S1 obtaining the actual sag value of the overhead line under icing meteorological conditions; S2 assuming that the icing thickness value of the overhead line is; S3 calculating the stress and load condition ratio of the overhead line under icing meteorological conditions according to the icing thickness value, and calculating the icing meteorological sag calculation value of the overhead line; S4 judging whether the iteration end condition is met according to the actual sag value and the icing meteorological sag calculation value, if it is met, outputting the current icing thickness value, if not, taking and repeating step S3, calculating the icing increment; S5 judging whether an early warning is needed according to the output icing thickness value. The present invention can effectively realize the accurate measurement and online monitoring of the icing thickness of overhead power transmission lines in extremely cold / foggy weather.

Description

Technical Field

[0001] The present invention relates to the technical field of online monitoring of power transmission lines, and in particular to a method, a device and a storage medium for monitoring icing of overhead lines. Background Art

[0002] With the frequent occurrence of severe weather and the expansion of the power grid, catastrophic meteorological events have become one of the most important factors affecting the safe and stable operation of the power grid, and ice damage is the most widespread and harmful type of damage. Under the influence of low temperature, freezing rain, wet snow and other weather conditions, the ice on the surface of the transmission line grows rapidly. Once the ice is too thick and ice breaks off or is affected by wind, it is very easy to cause power grid disasters such as ice flash of insulator strings, conductor dancing, hardware breakage, overload disconnection or tower collapse. At present, some commonly used online ice monitoring technologies in power grids, such as video monitoring technology, distributed optical fiber detection technology, mechanical calculation of ice load based on weighing method or horizontal tension-inclination method, calculation based on inclination-sag method, etc., all have problems such as insufficient accuracy and insufficient stability.

[0003] In this regard, the present invention provides a method, device and storage medium for monitoring ice coverage on overhead lines. Through the positioning accuracy and communication stability of Beidou satellites, a physical simulation and calculation model is created for inverting the ice thickness of overhead lines using sag and meteorological parameters. This can effectively solve the problem of online ice monitoring and observation of transmission lines, reduce the maintenance cost of transmission lines, and guide the safe operation of power grids. Summary of the invention

[0004] The present invention aims to provide an overhead line icing monitoring method, which aims to solve the problems of insufficient accuracy and insufficient stability in the online icing monitoring technology in the prior art. The specific technical solution is as follows:

[0005] An overhead line icing monitoring method, comprising:

[0006] Step S1: Obtaining the actual sag value of the overhead line under icing weather conditions ;

[0007] Step S2: Assume that the ice thickness of the overhead line is ,Pick Equal to initial value ;

[0008] Step S3: According to the ice thickness value Calculating stresses in overhead lines under icing conditions Load case ratio , according to the stress Load case ratio Calculate the meteorological sag value of icing overhead lines ;

[0009] Step S4: According to the actual sag value and calculated sag values ​​of icing meteorological Determine whether the iteration end condition is met. If so, output the current ice thickness value. If not satisfied, take Then repeat step S3; wherein, Calculate increments for ice cover;

[0010] Step S5: According to the output ice thickness value Determine whether an early warning is necessary;

[0011] In step S1: the spatial position data of the lowest point of the overhead line sag is obtained by Beidou positioning. The spatial position data is converted through the mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system, combined with the actual sag under non-icing meteorological conditions. Calculate the actual sag value under icing weather conditions .

[0012] In the above technical solution, the icing meteorological sag calculation value is preferably The calculation method is:

[0013] (1),

[0014] in, is the span of the overhead line, is the elevation difference angle of the overhead line.

[0015] The preferred technical solution is that the load condition ratio of the overhead line under icing weather conditions is The calculation method is:

[0016] = (2),

[0017] Overhead lines are covered with ice when the thickness is and wind speed Hourly ice weight load for:

[0018] (3),

[0019] Overhead lines are covered with ice when the thickness is and wind speed Hourly wind pressure load for:

[0020] (4),

[0021] Overhead lines are covered with ice when the thickness is and wind speed Vertical total load for:

[0022] (5),

[0023] in, is the standard ice density, is the wind speed, is the acceleration due to gravity, A is the cross-sectional area of ​​the overhead line, π is the circumference of a circle, is the diameter of the overhead line, b is the ice thickness, is the wind load adjustment factor, is the wind pressure span coefficient, is the wind carrier shape coefficient, is the standard value of the benchmark wind pressure; It is the deadweight load ratio of the overhead line.

[0024] The preferred technical solution is to calculate the stress of the overhead line under icing meteorological conditions according to the physical model of the icing state of the overhead line. , the physical model of ice covering state is:

[0025] (6),

[0026] in, E is the elastic modulus, is the span of the overhead line, is the height difference angle of the overhead line, is the stress of overhead lines under non-icing meteorological conditions, is the linear expansion coefficient of the overhead line, To obtain stress The temperature at is the temperature under icing meteorological conditions, Obtaining stress for overhead lines The load case specific load at It is the load condition ratio of overhead lines under icing meteorological conditions.

[0027] In the above technical solution, preferably, the stress state model of the overhead line under non-icing meteorological conditions is used to calculate the stress state of the overhead line under non-icing meteorological conditions. , the initial stress state model is:

[0028] (7),

[0029] in, The actual sag of the overhead line under non-icing meteorological conditions; based on the point cloud data of the overhead line, a three-dimensional model of the overhead line under non-icing meteorological conditions is established to obtain the actual sag of the overhead line under non-icing meteorological conditions .

[0030] In the above technical solutions, preferably, a mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system is established, specifically:

[0031] Get the actual sag at the lowest point of the overhead line sag The corresponding spatial position data is transformed into Gaussian coordinates through longitude and latitude coordinate conversion, and then the transformed Gaussian coordinates are mapped to the point cloud data coordinate system to establish a mapping relationship.

[0032] In the above technical solution, preferably, in step S4, the actual sag value and calculated sag values ​​of icing meteorological If formula (8) is satisfied, the current ice thickness value is output If not satisfied, take Then repeat step S3;

[0033] (8),

[0034] in, N is the judgment threshold.

[0035] The present invention also provides an overhead line icing monitoring device, which includes a power module, a monitoring module, a control module, a communication module, a fixing module and a data calculation module; the power module, the monitoring module, the control module, the communication module and the fixing module form a field installation device installed at the lowest point of the sag of the overhead line, the power module is used to supply power to the monitoring module, the control module, the communication module and the fixing module, the monitoring module is used to collect environmental data and spatial position data, the communication module is used to realize communication between the field installation device and the data calculation module, the fixing module is used to realize the installation of the field installation device on the overhead line, the control module is used to control the working status of the power module, the monitoring module and the fixing module, and the data calculation module executes the overhead line icing monitoring method to realize the monitoring of the icing status of the overhead line.

[0036] The present invention also provides a storage medium, in which the overhead line icing monitoring method is stored.

[0037] The application of the technical solution of the present invention has the following beneficial effects:

[0038] The overhead line icing monitoring method provided by the present invention is based on the positioning accuracy and communication stability of Beidou satellites, and uses sag, meteorological parameters and simulation calculation models to invert the ice thickness of overhead lines, effectively realizing the precise measurement and online monitoring of the ice thickness of overhead transmission lines in extremely cold / foggy weather, providing a data basis for the melting and de-icing of transmission lines and the analysis and prediction of line icing, which has great engineering significance.

[0039] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0041] Figure 1 is a flow chart of the overhead line icing monitoring method in Example 1;

[0042] Figure 2 is a framework diagram of an overhead line icing monitoring device in Example 2;

[0043] Figure 3 It is a structural schematic diagram of the on-site installation device in the overhead line icing monitoring device in Example 2. DETAILED DESCRIPTION

[0044] In order to facilitate the understanding of the present invention, the present invention will be described more fully below, and preferred embodiments of the present invention are provided. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0046] Embodiment 1:

[0047] See also Figure 1 This embodiment provides an overhead line icing monitoring method, including:

[0048] Step S1: Obtaining the actual sag value of the overhead line under icing weather conditions ;

[0049] Step S2: Assume that the ice thickness of the overhead line is ,Pick Equal to initial value ;

[0050] Step S3: According to the ice thickness value Calculating stresses in overhead lines under icing conditions Load case ratio , according to the stress Load case ratio Calculate the meteorological sag value of icing overhead lines ;

[0051] Step S4: According to the actual sag value and calculated sag values ​​of icing meteorological Determine whether the iteration end condition is met. If so, output the current ice thickness value. If not satisfied, take Then repeat step S3; wherein, Calculate increments for ice cover;

[0052] Step S5: According to the output ice thickness value Determine whether an early warning is necessary.

[0053] The following is a detailed description of each step:

[0054] Preferably, step S1 specifically includes:

[0055] S1.1. Collect point cloud data of overhead lines under non-icing meteorological conditions, establish a three-dimensional model of overhead lines under non-icing meteorological conditions based on the point cloud data of overhead lines, and obtain the actual sag of overhead lines under non-icing meteorological conditions ; Wherein, the three-dimensional model is obtained by fitting the point cloud data through a multi-point fitting curve algorithm.

[0056] S1.2. Under icing weather conditions, the spatial position data of the lowest point of the overhead line sag is obtained through Beidou positioning. The spatial position data is converted through the mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system, combined with the actual sag under non-icing weather conditions. Calculate the actual sag value under icing weather conditions .

[0057] Preferably, environmental data and spatial position data are obtained by installing a monitoring device at the lowest point of the sag of the overhead line, wherein the spatial position data is obtained by a Beidou positioning device, and the environmental data includes wind speed, temperature and humidity, which can be obtained by corresponding detection devices respectively, or by an integrated detection device for wind speed, temperature and humidity. Furthermore, installing a monitoring device at the lowest point of the sag of the overhead line does not affect the sag change of the overhead line.

[0058] In actual operation, the overhead line may be scanned to obtain point cloud data first, and then the monitoring device is installed at the lowest point of the sag of the overhead line. In this case, the mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system is established, specifically:

[0059] The environmental data when acquiring the overhead line point cloud data is used as the comparative environmental data, and the environmental data and spatial position data are collected in real time at the lowest point of the overhead line sag; if the real-time collected t If the environmental data at the moment is consistent with the comparison environmental data, t The spatial position data at a certain moment is transformed into Gaussian coordinates through longitude and latitude coordinate conversion, and then the transformed Gaussian coordinates are mapped to the point cloud data coordinate system to establish a mapping relationship.

[0060] It can be understood by those skilled in the art that since the coordinate system of Beidou data is different from the coordinate system of point cloud data, before the mapping relationship is established, the change of spatial position data cannot directly reflect the sag change of overhead lines; t If the environmental data at the moment is consistent with the comparison environmental data, it means that the overhead line t The sag at the time and the actual sag when collecting point cloud data Consistent, then t The spatial position data obtained by Beidou positioning at the moment corresponds to the actual sag , using this as the calculation zero point, the sag changes of the overhead lines can be directly obtained according to the changes in the spatial position data of Beidou positioning, that is, the sag changes of the overhead lines can be monitored through Beidou positioning.

[0061] Of course, in some embodiments, it is also possible to first install a monitoring device at the lowest point of the sag of the overhead line, and then scan the overhead line to obtain point cloud data. In this case, the actual sag obtained based on the point cloud data There is a spatial position data obtained by Beidou positioning at the same moment. In this case, a mapping relationship is established between the Beidou data coordinate system and the point cloud data coordinate system. Specifically, the spatial position data when scanning the point cloud data is transformed into Gaussian coordinates through longitude and latitude coordinate conversion, and then the transformed Gaussian coordinates are mapped to the point cloud data coordinate system. The mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system can also be directly established.

[0062] Preferably, the icing meteorological sag calculation value in step S3 is The calculation method is:

[0063] (1),

[0064] in, is the span of the overhead line, is the elevation difference angle of the overhead line.

[0065] Furthermore, the load conditions of overhead lines under icing weather conditions are The calculation method is:

[0066] = (2),

[0067] in, For overhead lines, the ice thickness is and wind speed The vertical total load ratio at For overhead lines, the ice thickness is and wind speed The ice weight load at For overhead lines, the ice thickness is and wind speed The wind pressure load ratio is is the deadweight load of the overhead line, ;

[0068] Preferably, ice weight specific load The calculation method is:

[0069] (3),

[0070] Preferably, the wind pressure ratio The calculation method is:

[0071] (4),

[0072] Preferably, the vertical total load ratio The calculation method is:

[0073] (5),

[0074] in, is the mass per unit length of the overhead line; is the standard ice density; is the wind speed; is the acceleration due to gravity;A is the cross-sectional area of ​​the overhead line; π is the ratio of pi; is the diameter of the overhead line; b is the ice thickness; is the wind load adjustment factor, is the wind pressure span coefficient, is the wind carrier shape coefficient, , , The values ​​are taken according to the corresponding wind load standards; is the standard value of the base wind pressure, =0.625 2 .

[0075] Furthermore, the stress of overhead lines under icing meteorological conditions is calculated based on the physical model of the icing state of overhead lines. , the physical model of ice covering state is:

[0076] (6),

[0077] in, E is the elastic modulus, is the span of the overhead line, is the height difference angle of the overhead line, is the stress of overhead lines under non-icing meteorological conditions, is the linear expansion coefficient of the overhead line, To obtain stress The temperature at is the temperature under icing meteorological conditions, Obtaining stress for overhead lines The load case specific load at It is the load condition ratio of overhead lines under icing meteorological conditions.

[0078] Specifically, for ice thickness After the assignment, the load condition ratio of the overhead line under icing weather conditions can be calculated according to formula (2)-formula (5): Then, according to formula (6), the stress of the overhead line under icing weather conditions is calculated: Finally, the ice thickness is calculated according to formula (1): Calculation value of meteorological sag of icing overhead lines .

[0079] Furthermore, after establishing a three-dimensional model based on point cloud data, the initial stress state model of the overhead line under non-icing meteorological conditions can be obtained through the simplified oblique parabola mechanical distribution force analysis. According to the initial stress state model of the overhead line under non-icing meteorological conditions, the stress of the overhead line under non-icing meteorological conditions can be calculated. ; The initial stress state model is:

[0080] (7),

[0081] in, It is the actual sag of the overhead line under non-icing meteorological conditions, that is, the actual sag of the overhead line when the point cloud data is scanned.

[0082] Preferably, in step S4, the actual sag value and calculated sag values ​​of icing meteorological If formula (8) is satisfied, the current ice thickness value is output If not satisfied, take Then repeat step S3; by continuously adjusting the ice thickness value Assign values ​​so that the calculated icing meteorological sag value Gradually approaching the actual value of sag , when the judgment condition formula (8) is met, it means that the ice thickness value at this time is Close to the actual ice thickness value on the overhead line, output the ice thickness value at this time That is, obtain the actual ice thickness value on the overhead line.

[0083] (8)

[0084] in, N The judgment threshold is generally 0.1%≤ N ≤0.5%.

[0085] Preferably, the ice thickness value in this embodiment is Initial value of Take 0.1mm, ice coverage calculation increment Take 0.1mm.

[0086] Preferably, in step S5 of this embodiment, when the output ice thickness value An early warning will be issued when the ice thickness of the overhead line reaches 60% of the design value.

[0087] Furthermore, in this embodiment, by recording the output ice thickness value b, a historical ice data change curve of the overhead line is formed.

[0088] The overhead line icing monitoring method provided in this embodiment is based on the positioning accuracy and communication stability of Beidou satellites, and uses sag, meteorological parameters and simulation calculation models to invert the ice thickness of overhead lines, effectively realizing the precise measurement and online monitoring of the ice thickness of overhead transmission lines in extremely cold / foggy weather, providing a data basis for transmission line de-icing and line icing analysis and prediction, and has great engineering significance.

[0089] Embodiment 2:

[0090] See also Figure 2-Figure 3 This embodiment provides an overhead line icing monitoring device, which includes a power module, a monitoring module, a control module, a communication module, a fixing module 1.1 and a data calculation module 2; the power module, the monitoring module, the control module, the communication module and the fixing module 1.1 form a field installation device 1 installed at the lowest point of the sag of the overhead line, the power module is used to power the monitoring module, the control module, the communication module and the fixing module, the monitoring module is used to collect environmental data and spatial position data, the communication module is used to realize communication between the field installation device 1 and the data calculation module 2, the fixing module is used to realize the installation of the field installation device 1 on the overhead line, the control module is used to control the working status of the power module, the monitoring module and the fixing module, and the data calculation module 2 executes the overhead line icing monitoring method in Example 1 to monitor the icing status of the overhead line.

[0091] Preferably, the power module is configured as a photovoltaic plus battery, which continues to charge when the power is less than 100%, and stops charging after being fully charged to 100% but still maintains a charging connection state.

[0092] Preferably, the monitoring module includes a wind speed, temperature, humidity integrated detection unit and a Beidou positioning device, and the Beidou positioning device is used to obtain spatial position data.

[0093] Preferably, the communication module is an integrated device (i.e., a substation), and the communication module and the main station can transmit data via 4G or Beidou communication.

[0094] Preferably, the fixing module includes a locking buckle, a transmission assembly and a driving motor. The driving motor outputs power to the transmission assembly, thereby driving the locking buckle to move so that the monitoring device is installed on the overhead line. The driving motor receives a control signal from the control module to operate. The fixing module can be used to mount the monitoring device on a drone. The control module receives a control command from a remote end and sends a control signal to drive the locking buckle to lock or unlock.

[0095] Preferably, the control module can control the monitoring frequency of the monitoring module. During the non-icing period, the monitoring frequency can be once a day to reduce the power consumption of the device and keep the device online. During the icing period, the minimum frequency can be selected as once every 10 minutes for high-frequency data collection.

[0096] Preferably, the data calculation module 2 is a remote computing center. When the output ice thickness value needs to be warned, the data calculation module can remind the staff through pop-up windows, sound and light warnings, etc. At the same time, the data calculation module also has a historical data recording function. By recording the ice thickness data information, a historical ice data change curve of the monitoring point is formed. In addition, when the monitoring data is missing, the data calculation module can issue an alarm to prompt. Further, the data calculation module includes a storage medium, and the storage medium stores the overhead line icing monitoring method in Example 1.

[0097] Preferably, when the monitoring device is installed on the overhead line, when the altitude monitoring data collected by the device at the front and rear positions along the line all show an increasing trend, it is considered that this place is the lowest point of the sag. After the position is selected correctly, the fixing device is controlled to fix it and separated from the installing drone, and the installation can be completed to monitor the environmental data and spatial position data.

[0098] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for monitoring icing of overhead lines, characterized in that: include: Step S1: Obtaining the actual sag value of the overhead line under icing weather conditions ; Step S2: Assume that the ice thickness of the overhead line is ,Pick Equal to initial value ; Step S3: According to the ice thickness value Calculating stresses in overhead lines under icing conditions Load case ratio , according to the stress Load case ratio Calculate the meteorological sag value of icing overhead lines ; Step S4: According to the actual sag value and calculated sag values ​​of icing meteorological Determine whether the iteration end condition is met. If so, output the current ice thickness value. If not satisfied, take Then repeat step S3; wherein, Calculate increments for ice cover; Step S5: According to the output ice thickness value Determine whether an early warning is necessary; In step S1: the spatial position data of the lowest point of the overhead line sag is obtained by Beidou positioning. The spatial position data is converted through the mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system, combined with the actual sag under non-icing meteorological conditions. Calculate the actual sag value under icing weather conditions ; Load case ratio of overhead lines under icing weather conditions The calculation method is: = （2）， Overhead lines are covered with ice when the thickness is and wind speed Hourly ice weight load for: （3）， Overhead lines are covered with ice when the thickness is and wind speed Hourly wind pressure load for: （4）， Overhead lines are covered with ice when the thickness is and wind speed Vertical total load for: （5）， in, is the standard ice density, is the wind speed, is the acceleration due to gravity, A is the cross-sectional area of ​​the overhead line, π is the circumference of a circle, is the diameter of the overhead line, b is the ice thickness, is the wind load adjustment factor, is the wind pressure span coefficient, is the wind carrier shape coefficient, is the standard value of the benchmark wind pressure; is the deadweight load of the overhead line; Calculate the stress of overhead lines under icing meteorological conditions based on the physical model of icing state of overhead lines , the physical model of ice covering state is: （6）， in, E is the elastic modulus, is the span of the overhead line, is the height difference angle of the overhead line, is the stress of overhead lines under non-icing meteorological conditions, is the linear expansion coefficient of the overhead line, To obtain stress The temperature at is the temperature under icing meteorological conditions, Obtaining stress for overhead lines The load case specific load at It is the load condition ratio of overhead lines under icing meteorological conditions.

2. The overhead line icing monitoring method according to claim 1, characterized in that: The calculated value of the icing meteorological sag The calculation method is: （1）， in, is the span of the overhead line, is the elevation difference angle of the overhead line.

3. The overhead line icing monitoring method according to claim 1, characterized in that: Calculate the stress of overhead lines under non-icing meteorological conditions based on the initial stress state model of overhead lines under non-icing meteorological conditions , the initial stress state model is: （7）， in, The actual sag of the overhead line under non-icing meteorological conditions; based on the point cloud data of the overhead line, a three-dimensional model of the overhead line under non-icing meteorological conditions is established to obtain the actual sag of the overhead line under non-icing meteorological conditions .

4. The overhead line icing monitoring method according to claim 1, characterized in that: Establish the mapping relationship between the Beidou data coordinate system and the point cloud data coordinate system, specifically: Get the actual sag at the lowest point of the overhead line sag The corresponding spatial position data is transformed into Gaussian coordinates through longitude and latitude coordinate conversion, and then the transformed Gaussian coordinates are mapped to the point cloud data coordinate system to establish a mapping relationship.

5. The overhead line icing monitoring method according to claim 1, characterized in that: In step S4, the actual sag value and calculated sag values ​​of icing meteorological If formula (8) is satisfied, the current ice thickness value is output If not satisfied, take Then repeat step S3; （8）， in, N is the judgment threshold.

6. An overhead line icing monitoring device, characterized in that: The monitoring device includes a power module, a monitoring module, a control module, a communication module, a fixing module and a data calculation module; the power module, the monitoring module, the control module, the communication module and the fixing module form a field installation device installed at the lowest point of the sag of the overhead line, the power module is used to supply power to the monitoring module, the control module, the communication module and the fixing module, the monitoring module is used to collect environmental data and spatial position data, the communication module is used to realize communication between the field installation device and the data calculation module, the fixing module is used to realize the installation of the field installation device on the overhead line, the control module is used to control the working status of the power module, the monitoring module and the fixing module, and the data calculation module executes the overhead line icing monitoring method as described in any one of claims 1-5 to realize the monitoring of the icing status of the overhead line.

7. A storage medium, characterized in that: The storage medium stores the overhead line icing monitoring method according to any one of claims 1 to 5.

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