Method, system and sensor for predicting development trend of icing disaster of power transmission line

Abstract

The invention relates to the technical field of icing disaster trend prediction, in particular to a method, a system and a sensor for predicting the development trend of an icing disaster of a power transmission line, and aims to solve the problem of how to accurately predict the theoretical maximum icing thickness according to weather data in the icing process of the power transmission line. The invention provides a prediction method. The prediction method comprises the steps of judging whether a power transmission line meets a historical icing standard or not according to meteorological information; determining current icing data of the power transmission line according to the real-time image and the ultrasonic sensor; predicting the theoretical maximum icing thickness of the power transmission line in the target time period according to the future weather data and the historical icing data; when the theoretical maximum icing thickness is greater than or equal to the thickness safety threshold value of the power transmission line, marking the power transmission line as a to-be-maintained line; and calculating the safety maintenance duration of the to-be-maintained line according to the second historical average icing rate, and determining the maintenance priority according to the safety maintenance duration.

Description

Technical Field

[0001] The present invention relates to the technical field of icing disaster trend prediction, and in particular to a method, system and sensor for predicting the development trend of icing disasters on power transmission lines. Background Art

[0002] The winter temperature in some southern provinces of my country is relatively high, and the humidity is also high. This climate feature means that when cold air invades, the temperature may drop rapidly to freezing point, causing the moisture in the air to condense at low temperatures and form frost. Frost gradually accumulates on the transmission line and eventually forms a thick layer of ice. When the ice thickness of the transmission line exceeds the design requirements, it may cause electrical faults such as flashover and line breakage, affecting the normal operation of the line; in severe cases, the ice-covered line will rub against insulators, poles and towers, generating corona discharge, further aggravating electrical problems. When the ice is too thick, the load on components such as transmission lines and poles may increase, resulting in serious incidents such as power outages, line breaks, and tower collapses, which will take a long time to repair and be difficult to restore. Therefore, it is of great significance to monitor the real-time ice coverage of transmission lines and study ice coverage prediction methods.

[0003] The real-time monitoring method of ice coverage of transmission lines is mainly based on video imaging. The image sensor installed on the tower collects the image of the transmission line around the tower, determines whether the line is covered with ice based on the image data, and uses the image edge features to determine the type and thickness of ice coverage. However, the lens is easily obscured by ice and snow, and potential moving interfering objects, such as birds, insects, windblown branches and plants, will interfere with the video collection, resulting in blurred image data.

[0004] At present, the research on transmission line icing prediction methods and systems is mainly concentrated in the field of artificial intelligence models. However, most of the existing icing prediction methods use the basic models in artificial intelligence models, with low prediction accuracy, and cannot fully explore the non-static and non-temporal characteristics of the icing growth process.

[0005] Based on this, in order to ensure the safe operation of transmission lines, it is urgent to establish a timely, accurate, high-precision and strong generalization method for predicting transmission line icing disasters. Summary of the invention

[0006] The problem solved by the present invention is: how to accurately predict the theoretical maximum ice thickness based on weather data during the icing process of a power transmission line.

[0007] To solve the above problems, an embodiment of the present invention provides a method for predicting the development trend of icing disasters on power transmission lines, the prediction method comprising: obtaining meteorological information within a current detection period, and judging whether the power transmission line meets the historical icing standard according to the meteorological information; when the power transmission line meets the historical icing standard, obtaining a real-time image of the power transmission line through an icing monitoring system, and determining the current icing data of the power transmission line according to the real-time image and an ultrasonic sensor; obtaining weather changes within a target time period, obtaining future weather data, obtaining historical icing data of the power transmission line in a first target area, and predicting the theoretical maximum icing thickness of the power transmission line within the target time period according to the future weather data and the historical icing data; when the theoretical maximum icing thickness is greater than or equal to the thickness safety threshold of the power transmission line, marking the power transmission line as a line to be maintained; obtaining the geographical location of the line to be maintained, and obtaining the second historical average icing rate of the line to be maintained according to the geographical location; calculating the safe maintenance time of the line to be maintained according to the second historical average icing rate, and determining the priority order of maintenance of the line to be maintained according to the safe maintenance time.

[0008] Compared with the existing technology, the technical effects achieved by adopting this technical solution are: first, the acquisition of historical icing standards in the target area can obtain icing conditions that are more in line with the current working environment of the transmission line. The acquisition of real-time images makes the current icing data more accurate and reliable. The prediction of the theoretical maximum icing thickness in the target time period allows the future working status of the transmission line to be intuitively reflected, allowing the staff to have enough time to maintain the transmission line. The thickness safety threshold setting accurately gives the staff the time to maintain the line to be maintained, which is convenient for the arrangement of the overall maintenance work. Second, the acquisition of the historical average icing rate fully considers the differences in the working areas of different lines to be maintained, improves the accuracy of the prediction of the theoretical maximum icing thickness, and the setting of the priority order makes the maintenance work arrangement of all lines to be maintained in the target area more reasonable.

[0009] In one embodiment of the present invention, weather changes within a target time period are obtained, future weather data are obtained, historical icing data of the transmission line in the first target area are obtained, and the theoretical maximum icing thickness of the transmission line within the target time period is predicted based on the future weather data and the historical icing data, specifically including: obtaining a basic icing rate within a second target area based on future weather data, calculating a first correction coefficient for the transmission line within the second target area based on the basic icing rate and the historical icing data; setting a second correction coefficient for the second target area based on a time node corresponding to the target time period; correcting the basic icing rate based on the first correction coefficient and the second correction coefficient to obtain a corrected icing rate; correcting the prediction model based on the corrected icing rate and the basic icing rate, and determining an icing rate prediction value in combination with current icing data and future weather data; and calculating the theoretical maximum icing thickness based on the time node corresponding to the target time period and the icing rate prediction value.

[0010] Compared with the prior art, the technical effects achieved by adopting the technical scheme are as follows: the setting of the first target area and the second target area fully considers the differences in the working environments of the transmission lines, thereby improving the accuracy of the predicted value of the icing rate; the setting of the first correction coefficient considers the changes in the icing rate of the transmission lines in the first target area and the second target area; by setting the target time period, the influence of different time periods on the icing rate is divided, thereby improving the flexibility and adaptability of the prediction model; the correction of the prediction model combined with historical icing data and future meteorological data helps to form a more comprehensive analysis perspective and improve the credibility of the prediction; the calculation of the theoretical maximum icing thickness provides an important reference basis for line maintenance, enabling staff to carry out maintenance in a timely manner.

[0011] In one embodiment of the present invention, a first correction coefficient of a transmission line in a second target area is calculated based on a basic icing rate and historical icing data, specifically comprising: obtaining historical icing data of the transmission line in the first target area, including a first historical average icing rate; obtaining future weather data in the second target area, and inputting it into an input layer of a prediction model to obtain the basic icing rate in the second target area; and calculating a first correction coefficient of the transmission line in the second target area based on the basic icing rate and historical icing data.

[0012] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the setting of the first historical average icing rate takes into account the overall trend and changes of icing suffered by the transmission lines in the first target area during the historical detection period; the calculation of the first correction coefficient combines the historical average icing rate in the first target area and the basic icing rate in the second target area, which can enable the prediction model to more accurately predict the icing risk of the transmission lines in a specific local area and remind maintenance personnel to take preventive measures in time.

[0013] In one embodiment of the present invention, a second correction coefficient for a second target area is set according to a time node corresponding to a target time period, specifically including: dividing each natural day into a plurality of ice-covered time periods, and dynamically adjusting the division method of the ice-covered time periods according to the specific season in which the natural day is located; obtaining the average temperature of each ice-covered time period and the minimum temperature of each natural day, and determining the second correction coefficient based on the average temperature and the minimum temperature.

[0014] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the setting of the second correction coefficient takes into account the influence of seasonal factors on the icing condition of the transmission lines in the second target area, and dynamically adjusts the division of icing time periods according to different seasons, so that the second correction coefficient can reflect the seasonal characteristics of icing; the setting of the icing time period takes into account the temperature change trend between day and night, which can enable the prediction model to more scientifically reflect the icing condition of the transmission lines in the second target area at different time stages; the calculation of the minimum temperature takes into account the minimum temperature characteristics of natural days in different seasons, which can improve the adaptability of the prediction model.

[0015] In one embodiment of the present invention, the safe maintenance time of the line to be maintained is calculated according to the second historical average ice coverage rate, and the priority order of maintenance of the line to be maintained is determined according to the safe maintenance time, specifically including: calculating the thickness difference between the theoretical maximum ice thickness and the thickness safety threshold; calculating the safe maintenance time according to the thickness difference and the second historical average ice coverage rate; determining the priority order according to the safe maintenance time.

[0016] Compared with the existing technology, the technical effects achieved by adopting this technical solution are as follows: the setting of the second historical icing rate takes into account the local working environment of the line to be maintained, improves the scientificity and accuracy of the calculation of the safe maintenance time, and the calculation of the thickness difference between the theoretical maximum icing thickness and the thickness safety threshold can specifically quantify the icing risk faced by the line to be maintained, thereby providing data support for subsequent maintenance decisions; the setting of the safe maintenance time can effectively identify the lines to be maintained that are most in need of priority maintenance, ensure that the lines to be maintained are maintained in a timely and effective manner, and improve the efficiency of maintenance work.

[0017] In one embodiment of the present invention, the priority order is determined according to the safety maintenance time, specifically including: when the difference between the safety maintenance time and the historical average safety maintenance time is greater than the first management threshold, the priority order is determined according to the maintenance time; when the difference is less than or equal to the first management threshold, the ice coverage rate prediction value of the line to be maintained is calculated, and the ice coverage rate difference between the ice coverage rate prediction value and the second historical average ice coverage rate is obtained; when the ice coverage rate difference is greater than the second management threshold, the priority order is determined according to the ice coverage rate difference; when the ice coverage rate difference is less than or equal to the second management threshold, the ice coverage difference between the theoretical maximum ice coverage thickness and the historical maximum ice coverage thickness is obtained; the maintenance record of the line to be maintained is obtained, and the priority order of the line to be maintained is determined according to the maintenance record and the ice coverage difference.

[0018] Compared with the prior art, the technical effects achieved by adopting this technical solution are as follows: the setting of the historical average safe maintenance time and the second historical average ice coverage rate takes into account the scientificity and rationality of the setting of the first threshold and the second threshold. The setting of the first threshold and the second threshold takes into account the maintenance requirements of different types of lines to be maintained, so as to ensure that the maintenance work of each line to be maintained can be effectively arranged according to the maintenance priority within the safe maintenance time, which not only improves the scientificity of maintenance decisions, but also enhances the flexibility of maintenance work. Specifically, the first threshold is a basic definition of the maintenance work time, which can help identify the lines to be maintained that need to be handled in priority, so as to ensure that they are maintained in a safe manner. Measures can be taken quickly to maintain the line to be maintained within the maintenance time, so as to avoid obstacles to the line to be maintained. The second threshold focuses on the change of ice coverage rate. The maintenance strategy is adjusted in time through the difference of ice coverage rate. The setting of the historical maximum ice coverage thickness takes into account the ice coverage load capacity of the line to be maintained under extreme weather conditions, which provides an important reference for maintenance decisions. The maintenance record can help identify the historical failure mode, maintenance frequency and equipment condition of the line to be maintained. When the maintenance record of a line to be maintained shows frequent failures or reduced working performance, combined with the difference in ice coverage thickness, its maintenance needs can be accurately evaluated, thereby optimizing the allocation of maintenance resources and improving maintenance efficiency. In one embodiment of the present invention, the maintenance record of the line to be maintained is obtained, and the priority order of the line to be maintained is determined according to the maintenance record and the ice coverage difference, specifically including: when the ice coverage difference is greater than the thickness threshold, determining the priority order of the line to be maintained according to the theoretical maximum ice coverage thickness; when the ice coverage difference is less than or equal to the thickness threshold, converting the ice coverage difference according to the maintenance record to obtain a converted difference; and determining the priority order of the line to be maintained according to the converted difference.

[0019] Compared with the existing technology, the technical effect achieved by adopting this technical solution is as follows: the setting of the ice difference takes into account the safe operation capability of the line to be maintained under different ice thicknesses, so as to reasonably arrange the maintenance priority order of the line to be maintained, give priority to high-risk lines to be maintained, and thus more effectively allocate maintenance resources to ensure that key lines to be maintained are maintained in time. The setting of the conversion difference takes into account the impact of the number of repairs on the ice thickness of the line to be maintained, and can specifically quantify the impact of the number of repairs on the ice thickness, so as to more comprehensively evaluate the actual ice situation of the line to be maintained and avoid misjudgment caused by a single data. Therefore, the introduction of the conversion difference can make up for the limitation of relying solely on the ice thickness, and provide a scientific and reasonable basis for determining the maintenance priority.

[0020] In one embodiment of the present invention, an ultrasonic sensor is provided, and the ultrasonic sensor is used to implement the method for predicting the development trend of icing disasters on power transmission lines recorded in the above embodiment. The ultrasonic sensor comprises: an ultrasonic probe, the ultrasonic probe is fixedly installed on the front of the transmission line, and the ultrasonic probe is used to detect a first distance from the ultrasonic sensor to the surface of the transmission line and a second distance from the ultrasonic sensor to the surface of the ice-covered transmission line, wherein the ultrasonic probe can calculate the ice thickness of the transmission line based on the first distance and the second distance.

[0021] Compared with the existing technology, the technical effect achieved by adopting this technical solution is: the setting of the ultrasonic sensor takes into account the reliability of the monitoring system under extreme weather conditions. It can adapt to different climate and environmental conditions, can operate stably under various weather conditions, and work together with the video image sensor to improve the accuracy and comprehensiveness of the monitoring system.

[0022] In one embodiment of the present invention, a prediction system for the development trend of icing disasters on transmission lines is also provided. The prediction method for the development trend of icing disasters on transmission lines recorded in the above embodiment is applied to the prediction system. The prediction system includes: a detection module, the detection module is used to detect meteorological information within the current detection period; a judgment module, the judgment module is used to judge whether the transmission line meets the historical icing standard according to the meteorological information; a calculation module, the calculation module is used to calculate the theoretical maximum ice thickness; a map module, the map module is used to store the geographical location of the line to be maintained. The prediction system has all the technical features of the above prediction method, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is one of the flow charts of the prediction method for the development trend of ice disasters on power transmission lines; Figure 2 This is the second flow chart of the prediction method for the development trend of ice disasters on power transmission lines; Figure 3 The third flow chart of the prediction method for the development trend of ice disasters on power transmission lines; Figure 4 This is the fourth flow chart of the prediction method for the development trend of ice disasters on power transmission lines; Figure 5 The fifth flow chart of the prediction method for the development trend of ice disasters on power transmission lines; Figure 6 A system diagram for predicting the development trend of ice disasters on power transmission lines; Figure 7 A monitoring system diagram for the development trend of ice disasters on power transmission lines; Description of reference numerals: 100-prediction system; 110-detection module; 120-judgment module; 130-calculation module; 140-map module; 200-monitoring system; 210-transmission line; 220-ultrasonic probe; L 1 - first distance; L 2 - Second distance. DETAILED DESCRIPTION

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0025] [First embodiment] See also Figure 1 In a specific embodiment, the present invention provides a method for predicting the development trend of icing disasters on power transmission lines, the prediction method comprising: S100, obtaining meteorological information in the current detection period, and judging whether the transmission line meets the historical icing standard according to the meteorological information; S200, when the transmission line meets the historical icing standard, obtaining a real-time image of the transmission line through an icing monitoring system, and determining current icing data of the transmission line according to the real-time image and the ultrasonic sensor; S300, obtaining weather changes within a target time period, obtaining future weather data, obtaining historical ice coverage data of the transmission lines in the first target area, and predicting the theoretical maximum ice coverage thickness of the transmission lines within the target time period based on the future weather data and the historical ice coverage data; S400, when the theoretical maximum ice thickness is greater than or equal to the thickness safety threshold of the transmission line, marking the transmission line as a line to be maintained; S500, obtaining a geographical location of the line to be maintained, and obtaining a second historical average ice coverage rate of the line to be maintained according to the geographical location; S600: Calculate the safe maintenance time of the line to be maintained according to the second historical average ice coverage rate, and determine the priority order of maintaining the line to be maintained according to the safe maintenance time.

[0026] In step S100, a natural year is divided into 12 detection cycles according to the month. The month in which the current natural day is located is the current detection cycle, and the detection cycle before the year or month in which the current natural day is located is recorded as the historical detection cycle. On each natural day, the weather information of the day is obtained through the weather forecast, and the transmission line is judged whether it meets the historical icing standard based on the meteorological information.

[0027] It should be noted that meteorological information includes but is not limited to the temperature, humidity, weather type and wind speed of the current natural day.

[0028] During the historical detection period, when the meteorological information meets the following conditions, the transmission line meets the historical icing standard: the temperature range is between 0~5℃, the relative humidity is maintained above 80%, the wind speed is controlled between 0 and 5.5 m / s, and there is dense fog and / or rain and / or snowfall, which lasts for more than 3 hours. For example, if the temperature in the area where the transmission line is located is -2℃, the air humidity is 85%, the wind speed is 5 m / s, and snowfall lasts for more than 3 hours, then it can be considered that the transmission line meets the historical icing standard.

[0029] In step S200, real-time images are acquired through multiple high-frame-rate video image sensors. These video image sensors monitor the same power transmission line in real time from different angles, synchronously capture image data at specific time intervals, and add timestamps. The image data captured at the moment is the real-time image. An image fusion algorithm is used to fuse the real-time images captured at the same time point, and the image data from multiple sources are synthesized into a high-quality fused image.

[0030] It should be noted that the specific time interval is 0.5-5s, preferably 0.5s, 1s and 2s, and the timestamp refers to the time information attached to the data or event, which is used to mark the specific time of each captured real-time image.

[0031] The installation height of the video image sensor is adjusted according to the actual height of the transmission line to ensure that all parts of the transmission line are covered. The tilt angle is adjusted to maximize the capture of dynamic changes in the transmission line and avoid information blind spots caused by viewing angle limitations.

[0032] In step S300, the target time period is usually 12 hours. During this period, there may be a large temperature difference between day and night, or sudden weather changes, which makes it difficult to predict the icing of the transmission line. For example, the temperature during the day is 3°C, and the transmission line itself is already in an iced state. Under the current working environment, as the transmission line operates, the thickness of the ice gradually decreases. However, future weather data shows that the temperature at night will drop sharply to -10°C. If the transmission line is not maintained in time during the day, the probability of failure of the transmission line will increase during the operation of the transmission line at night.

[0033] By using future weather data, the maximum ice thickness of the transmission lines within the target time period is predicted, allowing workers to have sufficient time to maintain each transmission line and improve the stability of transmission line operations in the target area.

[0034] In step S400 and step S500, the thickness safety threshold refers to the maximum ice thickness allowed during the operation of the transmission line. As long as the ice thickness is less than the ice safety threshold, the transmission line will not fail due to ice. The line to be maintained refers to a transmission line that is currently in normal working condition, but within the target time period, due to future weather changes, the ice thickness of the transmission line increases and exceeds the ice safety threshold. The geographical location of the line to be maintained is usually displayed in the system through the GIS map module. The staff can quickly plan the maintenance of the line to be maintained through the map displayed by the system. The differences in weather conditions and geographical environments in different regions result in different average ice rates in different regions. The meteorological conditions in some areas are more conducive to the formation of ice. For such areas, it is necessary to calculate their ice rates separately to improve the accuracy of the prediction model.

[0035] In step S600, under normal circumstances, the lines to be maintained will not fail to work due to ice thickness within the safe maintenance time. Therefore, the staff can reasonably arrange the maintenance sequence of all the lines to be maintained within the safe maintenance time, optimize the maintenance plan, and complete the maintenance work of all the lines to be maintained in a shorter time.

[0036] First, the acquisition of historical icing standards in the target area can obtain icing conditions that are more in line with the current working environment of the transmission line. The acquisition of real-time images makes the current icing data more accurate and reliable. The prediction of the theoretical maximum icing thickness in the target time period allows the future working status of the transmission line to be intuitively reflected, allowing the staff to have enough time to maintain the transmission line. The thickness safety threshold setting accurately gives the staff the time to maintain the line to be maintained, which is convenient for the arrangement of the overall maintenance work. Second, the acquisition of the historical average icing rate fully considers the differences in the working areas of different lines to be maintained, improves the accuracy of the prediction of the theoretical maximum icing thickness, and sets the priority order to make the maintenance work arrangement of all lines to be maintained in the target area more reasonable.

[0037] [Second embodiment] See also Figure 2 In a specific embodiment, weather changes in a target time period are obtained, future weather data are obtained, historical ice coverage data of the power transmission line in the first target area is obtained, and the theoretical maximum ice coverage thickness of the power transmission line in the target time period is predicted according to the future weather data and the historical ice coverage data, specifically including: S310, obtaining a basic icing rate within the second target area according to future weather data, and calculating a first correction coefficient of the transmission line within the second target area according to the basic icing rate and historical icing data; S320, setting a second correction coefficient for the second target area according to the time node corresponding to the target time period; S330, correcting the basic ice coating rate according to the first correction coefficient and the second correction coefficient to obtain a corrected ice coating rate; S340, correcting the prediction model according to the corrected ice covering rate and the basic ice covering rate, and determining the ice covering rate prediction value in combination with the current ice covering data and the future weather data; S350: Calculate the theoretical maximum ice thickness according to the time node corresponding to the target time period and the ice coverage rate prediction value.

[0038] In step S310, the future weather data in the second target area is input into the input layer of the prediction model, and the predicted value obtained is the basic ice coverage rate in the second target area. The historical ice coverage data includes the first historical average ice coverage rate in the first target area under the same weather data. According to the ratio of the first historical average ice coverage rate to the basic ice coverage rate, the first correction coefficient corresponding to the second target area is calculated.

[0039] In step S320, the time node refers to a specific time point within the target time period, the first target area refers to the macroscopic working environment of the transmission line, covering the geographical location through which the transmission line passes and the climate characteristics, topography, and ecosystem of its surrounding areas, and other factors; the second target area refers to the local working environment of the transmission line, including the close space of the supporting tower base, conductors, and accessories along the transmission line, etc. The second target area is included in the first target area. For example, the urban area where the transmission line is located and the climate characteristics, topography, and other factors of the urban area belong to the first target area, and different counties, towns, villages, and close spaces of the transmission line under the same urban area where the transmission line is located belong to the second target area.

[0040] It should be noted that the historical ice cover data of the first target area are usually counted and can be directly obtained. However, the second target area usually covers a smaller area. In some cases, there is no corresponding historical ice cover data for the second target area to obtain. At this time, after obtaining the basic ice cover rate through the prediction model, the future weather data is combined with the historical ice cover data of the first target area to obtain the first correction coefficient to obtain the actual ice cover conditions that meet the second target area.

[0041] In step S330 and step S340, the calculation of the modified ice coating rate needs to take into account the difference in the service life of the same transmission line in different working environments. Generally, the service life of the same transmission line is different in different working environments. Similarly, the ice thickness of the same transmission line will also be different under different weather conditions. Therefore, according to the ice coating condition in the second target area of ​​the transmission line, combined with the overall ice coating condition of the transmission line in the first target area, the modified ice coating rate is calculated, and the prediction model is corrected to obtain a more accurate ice coating rate prediction value. The calculation formula of the modified ice coating rate is as follows: in, R c To correct the ice coverage rate, the unit is mm / h, R b is the basic ice coverage rate, in mm / h, k 1 is the first correction coefficient, k 2 is the second correction factor.

[0042] The predicted value of icing rate is obtained through the multi-channel CNN-BiGRU-TPA prediction model. This prediction model extracts the characteristics of transmission line icing data from different angles and scales, captures the time series characteristics and long-term patterns of the data, and can predict the future icing rate of transmission lines based on meteorological data.

[0043] In step S350, the theoretical maximum ice thickness refers to the maximum ice thickness value that can be achieved by continuous ice coating at the predicted ice coating rate within the target time period, from the ice coating start time node to the ice coating end time node.

[0044] The setting of the first target area and the second target area fully considers the different working environments of the transmission lines and improves the accuracy of the ice coverage rate prediction value. The setting of the first correction coefficient considers the changes in the ice coverage rate of the transmission lines in the first target area and the second target area. By setting the target time period, the influence of different time periods on the ice coverage rate is divided, which improves the flexibility and adaptability of the prediction model. The correction of the prediction model combined with historical ice coverage data and future meteorological data helps to form a more comprehensive analysis perspective and improve the credibility of the prediction. The calculation of the theoretical maximum ice coverage thickness provides an important reference basis for line maintenance, enabling staff to carry out maintenance in a timely manner.

[0045] [Third embodiment] See also Figure 3 In a specific embodiment, calculating a first correction coefficient of the transmission line in the second target area according to the basic icing rate and the historical icing data specifically includes: S311, obtaining historical icing data of power transmission lines in a first target area, including a first historical average icing rate; S312, obtaining future weather data in the second target area, and inputting the data into an input layer of a prediction model, thereby obtaining a basic ice coverage rate in the second target area; S313: Calculate a first correction coefficient of the transmission line in the second target area according to the basic icing rate and historical icing data.

[0046] In step S311, the first historical average ice coverage rate is the arithmetic mean of multiple historical ice coverage rates, and the calculation formula is: in, is the first historical average ice coverage rate, in mm / h, R h is the historical ice coverage rate measured at different time points, in mm / h, i represents the i-th time point, and n is the number of measurements.

[0047] In step S313, the first correction coefficient is calculated based on the first historical average ice coverage rate and the basic ice coverage rate, and the calculation formula is: Among them, k 1 is the first correction coefficient, R b is the basic ice coverage rate, in mm / h, Rh is the historical ice coverage rate measured at different time points, in mm / h.

[0048] The setting of the first historical average icing rate takes into account the overall trend and changes in icing of the transmission lines in the first target area during the historical detection period. The calculation of the first correction coefficient combines the historical average icing rate in the first target area and the basic icing rate in the second target area, which can enable the prediction model to more accurately predict the icing risk of the transmission lines in a specific local area and remind maintenance personnel to take preventive measures in time.

[0049] [Fourth embodiment] See also Figure 3 In a specific embodiment, setting a second correction coefficient of the second target area according to a time node corresponding to the target time period specifically includes: S321, dividing each natural day into a plurality of ice-covered time periods, and dynamically adjusting the division method of the ice-covered time periods according to the specific season of the natural day; S322: Obtain the average temperature of each ice-covered time period and the minimum temperature of each natural day, and determine a second correction coefficient according to the average temperature and the minimum temperature.

[0050] In step S321, the specific season of the natural day is determined according to the season of the date corresponding to the natural day in the Gregorian calendar, and the division method of the ice-covered time period is determined based on the sunset time of the season of the natural day.

[0051] It should be noted that the sunset times in spring, summer, autumn and winter are different, especially in summer and winter. Therefore, when dividing the ice-covered time period, it is necessary to first determine the sunset time, and then divide each natural day into three time periods according to the specific meteorological conditions of the season in which the natural day is located, including the temperature drop stage from sunset to night, the stage before and after the lowest temperature of the day, and the temperature rise stage during the day, which are recorded as the first time period, the second time period and the third time period respectively. Specifically, spring includes March to May, and autumn includes September to November. The sunset times in these two seasons are similar, so each natural day in these two seasons can be divided into the following three time periods: The next three stages include: the first time period from 18:00 to 2:00, the second time period from 2:00 to 8:00, and the third time period from 8:00 to 18:00; the summer includes June to August, and each natural day is divided into three time periods, the first time period is from 19:00 to 2:00, the second time period is from 2:00 to 7:00, and the third time period is from 7:00 to 19:00; the winter includes December to February, and each natural day is divided into three time periods, the first time period is from 17:00 to 1:00, the second time period is from 1:00 to 9:00, and the third time period is from 9:00 to 17:00.

[0052] In step S321, the average temperature of each ice-covered time period is compared with the minimum temperature of each natural day to determine the second correction coefficient. The average temperature of the ice-covered time period is T 1 The lowest temperature of the natural day during the ice-covered period is T 2 , the second correction coefficient, the average temperature of the ice-covered period, and the minimum temperature of the natural day in which the ice-covered period occurs satisfy the following relationship: When T 1 =T 2 When K 2 =1; When T 1 <T 2 When K 2 =1.1; When T 1 >T 2 When K 2 =0.9.

[0053] For example, when the season of the natural day is winter and the ice-covered period is the first period, the average temperature of this period is calculated. If T 1 =-2℃, T 2 =1℃, then the second correction coefficient of the transmission line icing prediction model is determined to be 1.1. At this time, if the prediction model is not corrected, in the same working environment, the predicted value of the icing rate of the same transmission line is the basic icing rate. When the basic icing rate is 3mm / h, the predicted value of the icing rate obtained by the uncorrected prediction model is 3mm / h. After the prediction model is corrected, when the basic icing rate is 3mm / h, the first historical average icing rate is 2.50mm / h, the first correction coefficient is 1.05, and the second correction coefficient is 1.1. The calculated corrected icing rate is 3×1.1×1.05=3.465 mm / h. Correspondingly, the predicted value of the icing rate obtained by the corrected prediction model is compared with the predicted result obtained by the uncorrected model. The corrected predicted value of the icing rate increases. Then, in the same icing time period, the theoretical maximum icing thickness obtained according to the corrected icing rate prediction value also increases accordingly, which indicates that the transmission line will face a higher icing load, thereby reminding the staff to perform maintenance in time and reduce the risk of failure.

[0054] The setting of the second correction coefficient takes into account the impact of seasonal factors on the icing of transmission lines in the second target area, and dynamically adjusts the division of icing time periods according to different seasons, so that the second correction coefficient can reflect the seasonal characteristics of icing. The setting of the icing time period takes into account the temperature change trend between day and night, which can enable the prediction model to more scientifically reflect the icing conditions of transmission lines in the second target area at different time stages. The calculation of the minimum temperature takes into account the minimum temperature characteristics of natural days in different seasons, which can improve the adaptability of the prediction model.

[0055] [Fifth embodiment] See also Figure 4 In a specific embodiment, the safe maintenance time of the line to be maintained is calculated according to the second historical average ice coverage rate, and the priority order of maintaining the line to be maintained is determined according to the safe maintenance time, specifically including: S610, calculating the thickness difference between the theoretical maximum ice cover thickness and the thickness safety threshold; S620, calculating the safety maintenance time according to the thickness difference and the second historical average ice coverage rate; S630, determining a priority order according to the duration of security maintenance; In step S610, the calculation of the theoretical maximum ice thickness involves the ice start time node, ice end time node and ice rate prediction value within the target time period. The specific calculation formula is as follows: in, D m is the theoretical maximum ice thickness, in mm, R p is the predicted value of ice coverage rate, in mm / h, t 0 is the start time node of ice covering in the target time period, and t is the end time node of ice covering.

[0056] The thickness safety threshold is determined based on the historical ice coverage data of the transmission line. Usually, the minimum ice coverage thickness when the working state of the transmission line changes from normal to abnormal due to ice coverage is defined as the thickness safety threshold. The transmission line with a theoretical maximum ice coverage thickness greater than or equal to the thickness safety threshold is marked as a line to be maintained.

[0057] In steps S620 and S630, since the local working environment of the line to be maintained is different from the macroscopic working environment of the transmission line, it is more scientific and accurate to calculate the safe maintenance time based on the historical average ice coating rate of the line to be maintained. The average ice coating rate of the line to be maintained in its local working environment during the historical detection period is obtained and defined as the second historical average ice coating rate. The safe maintenance time refers to the time required for the ice coating thickness to reach the thickness safety threshold from the theoretical maximum ice coating thickness when the line to be maintained is continuously iced at the second historical average ice coating rate. The calculation formula is as follows: Among them, t 1 It is the duration of security maintenance, in hours. D m is the theoretical maximum ice thickness, D s is the thickness safety threshold, in mm, is the second historical average ice coverage rate, in mm / h.

[0058] The setting of the second historical icing rate takes into account the local working environment of the line to be maintained, improves the scientificity and accuracy of the calculation of the safe maintenance time, and the calculation of the thickness difference between the theoretical maximum icing thickness and the thickness safety threshold can specifically quantify the icing risk faced by the line to be maintained, thereby providing data support for subsequent maintenance decisions. The setting of the safe maintenance time can effectively identify the lines to be maintained that are most in need of priority maintenance, ensure that the lines to be maintained are maintained in a timely and effective manner, and improve the efficiency of maintenance work.

[0059] [Sixth embodiment] See also Figure 5 In a specific embodiment, the priority order is determined according to the security maintenance duration, specifically including: S631. When the difference between the security maintenance duration and the historical average security maintenance duration is greater than a first management threshold, determine the priority order according to the maintenance duration; S632: when the difference is less than or equal to the first management threshold, calculate the predicted ice rate of the line to be maintained, obtain the ice rate difference between the predicted ice rate and the second historical average ice rate, and when the ice rate difference is greater than the second management threshold, determine the priority order according to the ice rate difference; S633: when the ice coverage rate difference is less than or equal to the second management threshold, obtaining the ice coverage difference between the theoretical maximum ice coverage thickness and the historical maximum ice coverage thickness; S634: Obtain maintenance records of the lines to be maintained, and determine the priority order of the lines to be maintained according to the maintenance records and the ice coverage difference.

[0060] In steps S631 and S632, the historical average safety maintenance time refers to the ratio of the total maintenance time of the line to be maintained within the historical detection period to the number of maintenance times, that is, the average maintenance time of the line to be maintained. The first management threshold and the second management threshold refer to pre-set safety maintenance standards, which are used to evaluate the urgency of maintenance work. Specifically, the first management threshold is intended to reflect the fluctuation range of the safety maintenance time within the normal maintenance period of the line to be maintained, and is usually set to 10% of the historical average safety maintenance time, so as to timely identify the line to be maintained that exceeds the normal maintenance period. The second management threshold is used to measure whether the change in the icing rate significantly affects the line stability, and is usually set to 5% of the second historical average icing rate, to ensure that the lines to be maintained with a higher risk of icing can be given priority maintenance under severe weather conditions, thereby reducing the risk of icing disasters in the lines to be maintained.

[0061] In step S633, the historical maximum ice thickness refers to the maximum ice load that the line to be maintained can withstand when operating normally within the historical detection period.

[0062] In step S634, the maintenance record is a detailed record of all maintenance and repairs of the line to be maintained within the historical detection period, which reflects the frequency of failures and maintenance requirements of the line to be maintained.

[0063] The setting of the historical average safe maintenance time and the second historical average ice coverage rate takes into account the scientificity and rationality of the setting of the first threshold and the second threshold. The setting of the first threshold and the second threshold takes into account the maintenance needs of different types of lines to be maintained, so as to ensure that the maintenance work of each line to be maintained can be effectively arranged according to the maintenance priority within the safe maintenance time, which not only improves the scientificity of maintenance decisions, but also enhances the flexibility of maintenance work. Specifically, the first threshold is the basic definition of the maintenance work time, which can help identify the lines to be maintained that need to be given priority, so as to ensure that measures can be taken quickly to maintain the lines to be maintained within the safe maintenance time, thereby avoiding obstacles to the lines to be maintained. The second threshold focuses on the change of ice coverage rate, and the maintenance strategy is adjusted in time through the difference in ice coverage rate. The setting of the historical maximum ice coverage thickness takes into account the ice coverage load capacity of the lines to be maintained under extreme weather conditions, which provides an important reference for maintenance decisions. The maintenance record can help identify the historical failure mode, maintenance frequency and equipment condition of the lines to be maintained. When the maintenance record of a line to be maintained shows frequent failures or reduced working performance, combined with the difference in ice coverage thickness, its maintenance needs can be accurately evaluated, thereby optimizing the allocation of maintenance resources and improving maintenance efficiency.

[0064] [Seventh embodiment] See also Figure 5In a specific embodiment, the maintenance records of the lines to be maintained are obtained, and the priority order of the lines to be maintained is determined according to the maintenance records and the ice coverage difference, which specifically includes: S634a, when the ice cover difference is greater than the thickness threshold, determining the priority order of the lines to be maintained according to the theoretical maximum ice cover thickness; S634b, when the ice cover difference is less than or equal to the thickness threshold, convert the ice cover difference according to the maintenance record to obtain a converted difference; S634c. Determine the priority order of the lines to be maintained according to the converted difference.

[0065] In step S634a, the thickness threshold is a pre-set safety standard used to determine the impact of the icing state of the line to be maintained on its working state. When the difference between the theoretical maximum icing thickness and the historical maximum icing thickness exceeds the thickness threshold, it may cause the line to be maintained to fail. Therefore, the setting of the thickness threshold is usually based on 20% of the historical maximum icing thickness to ensure that maintenance measures are taken in time when the actual icing situation is close to the historical maximum value, thereby effectively reducing the risk of failure of the line to be maintained and ensuring its safe operation.

[0066] In steps S634b and S634c, the ice coverage difference needs to be converted according to the maintenance records. The reason is that once a transmission line fails and undergoes maintenance, its subsequent working state often cannot be restored to the initial stable state. Transmission lines that have been repaired many times may contain deeper problems, such as material fatigue, structural aging, etc. These factors will cause the line to show greater vulnerability when facing icing disasters. Therefore, for lines to be maintained that have failed in a short period of time, the evaluation criteria for their maintenance priority should be more stringent. The more failures there are, the less ideal the operating conditions of the line to be maintained, and there may be higher risks. In this case, although the ice coverage difference of the line to be maintained is less than or equal to the ice thickness threshold, its risk of failure may be higher than those lines to be maintained with fewer maintenance records. Therefore, the ice coverage difference is converted by the number of repairs to obtain an ice thickness that is more in line with the actual working state of the line to be maintained. The specific formula is as follows: Among them, k 3 is the weight coefficient, which indicates the influence of the number of maintenance times on the icing risk. If the number of maintenance times is less than or equal to 3 times, k is set 3 is 0.1, the number of maintenance times is greater than 3 times and less than or equal to 5 times, set k 3 is 0.3, the number of maintenance times is greater than 5, and k is set 3 is 0.4.

[0067] For example, when the theoretical maximum ice thickness of the line to be maintained is 17mm, the historical maximum ice thickness is 20mm, the number of maintenance times is 6, the calculated thickness threshold is 4mm, the ice difference is 3mm, and the conversion difference is -4.2mm. That is to say, the actual ice difference of the line to be maintained is -4.2mm, and its theoretical maximum ice thickness also increases accordingly to 24.2mm, indicating that the risk of failure due to icing on the line to be maintained is high in the current working environment, and the maintenance priority should be adjusted dynamically.

[0068] The setting of the ice difference takes into account the safe operation capability of the lines to be maintained under different ice thicknesses, so as to reasonably arrange the maintenance priority of the lines to be maintained, give priority to high-risk lines to be maintained, and allocate maintenance resources more effectively to ensure that key lines to be maintained are maintained in time. The setting of the conversion difference takes into account the impact of the number of repairs on the ice thickness of the lines to be maintained, and can specifically quantify the impact of the number of repairs on the ice thickness, so as to more comprehensively evaluate the actual ice situation of the lines to be maintained and avoid misjudgment caused by single data. Therefore, the introduction of the conversion difference can make up for the limitations of relying solely on ice thickness and provide a scientific and reasonable basis for determining maintenance priorities.

[0069] [Eighth embodiment] See also Figure 6 In a specific embodiment, an ultrasonic sensor is provided. The ultrasonic sensor is used to implement the method for predicting the development trend of ice disasters on power transmission lines described in the above embodiment. The ultrasonic sensor includes: Ultrasonic probe 220, which is fixedly mounted on the front of the power transmission line 210, and is used to detect the first distance from the ultrasonic sensor to the surface of the power transmission line 210 L 1 and a second distance from the ultrasonic sensor to the ice-covered surface of the transmission line 210 L 2 , wherein the ultrasound probe can be based on the first distance L 1 and the second distance L 2 Calculate the ice thickness on transmission lines.

[0070] It should be noted that when the ultrasonic probe 220 receives the returned ultrasonic signal, the amplifier is used to amplify the signal, and the amplified signal is filtered to remove noise and unnecessary frequency components, and the effective ultrasonic signal is retained. The ice thickness of the transmission line 210 is the first distance L 1 and the second distance L 2 The difference.

[0071] The setting of the ultrasonic sensor takes into account the reliability of the monitoring system 200 under extreme weather conditions. It can adapt to different climate and environmental conditions, can operate stably under various weather conditions, and work together with the video image sensor to improve the accuracy and comprehensiveness of the monitoring system 200. [Ninth embodiment] See also Figure 7 In a specific embodiment, the present invention further provides a prediction system 100 for the development trend of icing disasters on power transmission lines. The prediction method for the development trend of icing disasters on power transmission lines recorded in the above embodiment is applied to the prediction system 100. The prediction system 100 includes: a detection module 110, the detection module 110 is used to detect meteorological information within the current detection period; a judgment module 120, the judgment module 120 is used to judge whether the power transmission line meets the historical icing standard according to the meteorological information; a calculation module 130, the calculation module 130 is used to calculate the theoretical maximum ice thickness; a map module 140, the map module 140 is used to store the geographical location of the line to be maintained. The prediction system has all the technical features of the above prediction method, which will not be repeated here.

[0072] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for predicting the development trend of icing disasters on power transmission lines, characterized in that: The prediction method comprises: Acquire meteorological information in a current detection period, and determine whether the transmission line meets the historical icing standard according to the meteorological information; When the transmission line meets the historical icing standard, a real-time image of the transmission line is obtained through an icing monitoring system, and current icing data of the transmission line is determined according to the real-time image and an ultrasonic sensor; Obtain weather changes within a target time period, obtain future weather data, obtain historical icing data of the power transmission lines in a first target area, and predict a theoretical maximum icing thickness of the power transmission lines within the target time period based on the future weather data and the historical icing data; When the theoretical maximum ice thickness is greater than or equal to a thickness safety threshold of the transmission line, marking the transmission line as a line to be maintained; Acquire the geographical location of the line to be maintained, and acquire a second historical average ice coverage rate of the line to be maintained according to the geographical location; The safe maintenance duration of the line to be maintained is calculated according to the second historical average ice coverage rate, and the priority order of maintaining the line to be maintained is determined according to the safe maintenance duration.

2. The method for predicting the development trend of icing disasters on power transmission lines according to claim 1 is characterized in that: The step of obtaining weather changes within a target time period, obtaining future weather data, obtaining historical ice coverage data of the power transmission line in the first target area, and predicting the theoretical maximum ice coverage thickness of the power transmission line within the target time period according to the future weather data and the historical ice coverage data specifically includes: Acquire a basic ice coverage rate in a second target area according to the future weather data; Calculating a first correction coefficient of the power transmission line in the second target area according to the basic icing rate and the historical icing data; Setting a second correction coefficient for the second target area according to a time node corresponding to the target time period; Correcting the basic ice coating rate according to the first correction coefficient and the second correction coefficient to obtain a corrected ice coating rate; Correcting the prediction model according to the modified ice covering rate and the basic ice covering rate, and determining the ice covering rate prediction value in combination with the current ice covering data and the future weather data; The theoretical maximum ice thickness is calculated according to the time node corresponding to the target time period and the ice coverage rate prediction value.

3. The method for predicting the development trend of icing disasters on power transmission lines according to claim 2 is characterized in that: The calculating the first correction coefficient of the power transmission line in the second target area according to the basic icing rate and the historical icing data specifically includes: Acquire the historical icing data of the power transmission line in the first target area, including a first historical average icing rate; Acquire the future weather data in the second target area, and input the future weather data into the input layer of the prediction model, so as to acquire the basic ice coverage rate in the second target area; The first correction coefficient of the transmission line in the second target area is calculated according to the basic icing rate and the historical icing data.

4. The method for predicting the development trend of icing disasters on power transmission lines according to claim 2 is characterized in that: The step of setting the second correction coefficient of the second target area according to the time node corresponding to the target time period specifically includes: Dividing each natural day into a plurality of ice-covered time periods, and dynamically adjusting the division method of the ice-covered time periods according to the specific season of the natural day; The average temperature of each ice-covered time period and the minimum temperature of each natural day are obtained, and the second correction coefficient is determined according to the average temperature and the minimum temperature.

5. The method for predicting the development trend of icing disasters on power transmission lines according to claim 1, characterized in that: The calculating the safe maintenance duration of the line to be maintained according to the second historical average ice coverage rate, and determining the priority order of maintaining the line to be maintained according to the safe maintenance duration, specifically includes: Calculating a thickness difference between the theoretical maximum ice coverage thickness and the thickness safety threshold; Calculating the safety maintenance duration according to the thickness difference and the second historical average ice coverage rate; The priority order is determined according to the security maintenance duration.

6. The method for predicting the development trend of icing disasters on power transmission lines according to claim 5, characterized in that: Determining the priority order according to the security maintenance duration specifically includes: When the difference between the safety maintenance duration and the historical average safety maintenance duration is greater than a first management threshold, determining the priority order according to the maintenance duration; When the difference is less than or equal to the first management threshold, calculating the predicted ice-covering rate of the line to be maintained, obtaining the ice-covering rate difference between the predicted ice-covering rate and the second historical average ice-covering rate, and when the ice-covering rate difference is greater than the second management threshold, determining the priority order according to the ice-covering rate difference; When the ice coverage rate difference is less than or equal to the second management threshold, obtaining the ice coverage difference between the theoretical maximum ice coverage thickness and the historical maximum ice coverage thickness; The maintenance records of the lines to be maintained are obtained, and the priority order of the lines to be maintained is determined according to the maintenance records and the ice coverage difference.

7. The method for predicting the development trend of icing disasters on power transmission lines according to claim 6, characterized in that: The obtaining of the maintenance record of the line to be maintained, and determining the priority order of the line to be maintained according to the maintenance record and the ice coverage difference specifically includes: When the ice coverage difference is greater than a thickness threshold, determining the priority order of the lines to be maintained according to the theoretical maximum ice coverage thickness; When the ice coverage difference is less than or equal to the thickness threshold, converting the ice coverage difference according to the maintenance record to obtain a converted difference; The priority order of the lines to be maintained is determined according to the conversion difference.

8. An ultrasonic sensor, characterized in that: The ultrasonic sensor is used to implement the method for predicting the development trend of icing disasters on power transmission lines according to any one of claims 1 to 7, and the ultrasonic sensor comprises: An ultrasonic probe, the ultrasonic probe is fixedly mounted on the front of the transmission line, and the ultrasonic probe is used to detect a first distance from the ultrasonic sensor to the surface of the transmission line and a second distance from the ultrasonic sensor to the ice-covered surface of the transmission line; The ultrasonic probe is capable of calculating the ice thickness of the transmission line according to the first distance and the second distance.

9. A system for predicting the development trend of icing disasters on power transmission lines, characterized in that: The prediction method according to any one of claims 1 to 7 is applied to the prediction system, wherein the prediction system comprises: A detection module, the detection module is used to detect the meteorological information within the current detection period; A judgment module, the judgment module is used to judge whether the transmission line meets the historical icing standard according to the meteorological information; A calculation module, the calculation module is used to calculate the theoretical maximum ice thickness; A map module is used to store the geographical location of the line to be maintained.

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