Power transmission line lightning path early warning method based on full flash movement direction and coverage

Abstract

The present application relates to the field of lightning monitoring and early warning, and specifically discloses a power transmission line lightning path early warning method based on total lightning movement direction and coverage range. The method identifies lightning active areas based on a multi-level neighborhood method lightning active area real-time monitoring algorithm, predicts the total lightning movement direction and coverage range of the lightning active area in a thunderstorm process under consideration of the merging and splitting process of the lightning active area, constructs a power transmission line early warning area and early warning index, and issues a power transmission line early warning signal. The method real-time monitors and predicts lightning disaster conditions of each line, calculates the time when a thunderstorm is expected to reach a key tower and the line section that may be affected, realizes fine early warning of "one line, one case" and "one tower, one strategy", and has great engineering practical value and economic significance for ensuring the safe and stable operation of important power transmission channels such as extra-high voltage and cross-region power grids.

Description

Technical Field

[0001] This invention belongs to the field of lightning monitoring and early warning, specifically a method for early warning of lightning paths on transmission lines based on the entire direction of lightning movement and coverage. Background Technology

[0002] Lightning strikes are the leading cause of power outages on overhead transmission lines. Lightning strikes can directly hit conductors or towers, or cause faults through induced overvoltages, seriously threatening the stable operation of the power grid. Although meteorological departments provide lightning activity forecasting and early warning services, industry and scale differences affect the accuracy of lightning warnings. Traditional post-fault maintenance in power systems is passive and inefficient. Operation and maintenance departments urgently need a technology that can predict lightning strike risks in advance to activate early warning and emergency mechanisms, achieving a shift from passive lightning protection to proactive lightning avoidance and prevention. To better implement proactive lightning protection technology in power systems, real-time lightning monitoring and early warning services for power equipment are necessary.

[0003] A key technology in lightning warning research is the study of lightning warning methods based on the entire lightning movement path. This patent discloses a lightning path warning method for transmission lines based on the entire lightning movement direction and coverage area. This method identifies active lightning regions using a multi-level neighborhood method for real-time monitoring of active lightning regions. Considering the merging and splitting processes of active lightning regions, it predicts the entire lightning movement direction and coverage area of ​​active lightning regions during a thunderstorm, constructs warning areas and indicators for transmission lines, and issues warning signals. This method monitors and predicts the lightning damage situation of each line in real time, calculates the expected arrival time of the thunderstorm at key towers and the line sections that may be affected, achieving refined early warning with "one plan per line" and "one policy per tower." This has significant engineering practical value and economic significance for ensuring the safe and stable operation of important transmission channels such as ultra-high voltage and inter-regional power grids. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for early warning of lightning paths on transmission lines based on the overall direction of lightning movement and coverage area. This method solves the problems in existing lightning warning technologies, such as industry and scale differences, inability to achieve refined early warning of transmission lines, and difficulty in predicting the specific time and affected sections of thunderstorms reaching key towers, which leads to the power system only being able to passively respond to lightning strike faults.

[0005] The method for early warning of lightning paths on transmission lines based on the direction and coverage of all lightning movements first identifies active lightning regions within a time interval based on all lightning data, tracks the active lightning movement path, and extracts real-time monitoring results of lightning activity. Second, considering the merging and splitting process of active lightning regions, it predicts the direction and coverage of all lightning movements within the active lightning regions. Finally, based on the prediction results of active lightning regions, it issues early warning results for each transmission line.

[0006] The real-time monitoring algorithm for lightning active areas based on the multi-level neighborhood method includes the following steps:

[0007] Step 1: Set the time interval The time intervals are integer multiples of 1 minute. Within each time interval, all lightning data are distributed in a geographic grid based on geographic coordinates to form a lightning density map.

[0008] Step 2: Use the multi-level neighborhood method to divide the lightning activity area within the time interval. First, identify the grid containing lightning events according to the eight-neighbor method to form the primary lightning active area. Then, set the spatial distance threshold according to the distance between the lightning active areas. Lightning active areas less than the threshold are merged to form the final lightning active area.

[0009] Step 3: Based on the process of merging and splitting of active lightning regions, pair up active lightning regions within consecutive time intervals to form the trajectory of active lightning regions during the thunderstorm process;

[0010]

[0011] In the formula, For the predicted speed of movement of lightning active areas, and These represent the movement speeds of each sub-region at the current and previous moments, respectively. The area of ​​each sub-region, This is the weighting coefficient, with a value ranging from 0.5 to 0.8; , These represent the number of rows and columns of the grid, respectively.

[0012] The prediction of lightning activity areas and movement paths for thunderstorm processes that consider the merging and splitting processes includes the following steps:

[0013] Step 1: Based on historical speeds and considering merging and splitting, predict the movement speed of lightning activity areas for the next three time intervals as follows:

[0014]

[0015]

[0016]

[0017] In the formula, , , For the future , , Predicting speed at any given moment and These are the current time and the previous time respectively. Line number The movement speed of the sub-region, The area of ​​each sub-region, These are the weighting coefficients;

[0018] Step 2: Based on the centroid velocity of the active lightning region, determine the future values ​​corresponding to each active lightning region. 2 and 3 Location, direction, and extent of lightning activity;

[0019] Step 3: Quantitatively evaluate the thunderstorm activity forecast results using three indicators: Point of Detection (POD), False Alarm Rate (FAR), and Critical Success Index (CSI).

[0020]

[0021]

[0022]

[0023] In the formula, The number of times a prediction was made correctly. The number of times the report was missed. This refers to the number of times false reporting occurred.

[0024] Constructing early warning zones and indicators for transmission lines includes the following steps:

[0025] Step 1: Divide the transmission line early warning area into three levels according to distance, setting them as 2 km, 5 km, and 10 km respectively. class, Level and Level 1 warning area;

[0026] Step 2: After real-time monitoring and prediction of the lightning activity area trajectory, it is necessary to determine whether it will pass through the power transmission line warning area;

[0027] Step 3: When the predicted trajectory of the active lightning area intersects with the transmission line, the active lightning area passes through the transmission line area. The estimated time for the active lightning area to reach the transmission line warning area is:

[0028]

[0029]

[0030]

[0031] In the formula, The shortest distance from the boundary of a lightning-active area to a power transmission line, in km; Predicted speeds for areas of high lightning activity, in km / min; , , Reaching the active lightning zone class, Level and The time required for a Level 1 warning area is measured in minutes.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. This invention, by fusing three-dimensional lightning location data, can map the movement path of lightning activity during thunderstorms in real time, thereby improving the active lightning monitoring capability of transmission lines;

[0034] 2. This invention considers the merging and splitting process of lightning active area trajectories. By analyzing the changes in the movement speed, direction and intensity of lightning active areas, it predicts the lightning active areas and movement paths during thunderstorms, which can effectively extend the warning time and leave valuable operation time for the power grid dispatch center.

[0035] 3. The early warning area and early warning indicators for transmission lines proposed in this invention can perform spatial overlay analysis of the predicted lightning movement path and the precise geographical coordinates and orientation of the power grid towers, calculate the expected time of the thunderstorm reaching the key towers and the line sections that may be affected, realize the refined early warning of "one plan for one line" and "one policy for one tower", and can be directly linked to the production management system to initiate targeted inspections or emergency repair preparations.

[0036] 4. The method of this invention can effectively improve the monitoring and early warning capabilities of lightning activity on transmission lines, and monitor and predict the lightning disaster situation of each line in real time. It has significant engineering practical value and economic significance for ensuring the safe and stable operation of important transmission channels such as ultra-high voltage and inter-regional power grids. Attached Figure Description

[0037] Figure 1 This is a flowchart of the transmission line lightning path early warning method based on the entire lightning movement direction and coverage area of ​​the present invention.

[0038] Figure 2 This is a schematic diagram of the overhead line lightning early warning method based on the entire lightning movement path according to the present invention; wherein, Figure 2 (a) is a distribution map of all lightning data. Figure 2 (b) is a geographic grid division map. Figure 2 (c) is a lightning density map. Figure 2 (d) is a map identifying areas of active lightning. Figure 2 (e) is a schematic diagram of the movement path prediction and early warning area;

[0039] Figure 3 This is a flowchart of the real-time monitoring algorithm for lightning active areas based on the multi-level neighborhood method of this invention;

[0040] Figure 4 This invention considers the prediction flowchart of lightning active area and movement path of thunderstorm process considering the merging and splitting process;

[0041] Figure 5 A flowchart for constructing early warning areas and early warning indicators for power transmission lines is provided for this invention. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] like Figure 1 The method for lightning path early warning of transmission lines based on the entire lightning movement direction and coverage area first identifies active lightning regions within a time interval based on total lightning data, tracks the active lightning movement path, and extracts real-time monitoring results of lightning activity. Second, considering the merging and splitting process of active lightning regions, it predicts the entire lightning movement direction and coverage area of ​​the active lightning regions. Finally, based on the lightning activity region prediction results, early warning results are issued for each transmission line. A schematic diagram of the overhead line lightning early warning method based on the entire lightning movement path is shown below. Figure 2 .

[0044] A real-time monitoring algorithm for lightning active regions based on a multi-level neighborhood method is as follows: Figure 3 As shown:

[0045] Step 1: Collect all lightning data acquired by the all-lightning location system (see...) Figure 2 (a) ) gridding the coverage area of ​​the All Lightning Positioning System (see Figure 2 (b) Setting the time interval The time interval is an integer multiple of 1 minute. The total lightning data is distributed across a geographic grid based on geographic coordinates, forming a lightning density map, see [link / reference]. Figure 2 (c);

[0046] Step 2: A multi-level neighborhood method is used to divide the lightning activity area within the time interval. First, the grid containing lightning events is identified using the eight-neighbor method to form primary lightning active areas. Then, a spatial distance threshold is set based on the distance between the lightning active areas. Lightning active areas smaller than the threshold are merged to form the final lightning active area. (See...) Figure 2 (d);

[0047] Step 3: Based on the process of merging and splitting of active lightning regions, pair up active lightning regions within consecutive time intervals to form the trajectory of active lightning regions during the thunderstorm process;

[0048]

[0049] In the formula, For the predicted speed of movement of lightning active areas, and These represent the movement speeds of each sub-region at the current and previous moments, respectively. The area of ​​each sub-region, This is the weighting coefficient, with a value ranging from 0.5 to 0.8; , These represent the number of rows and columns of the grid, respectively.

[0050] The flowchart for predicting the active lightning region and movement path of thunderstorm processes considering the merging and splitting process is shown below. Figure 4 :

[0051] Step 1: Based on historical speeds and considering merging and splitting, predict the movement speed of lightning activity areas for the next three time intervals as follows:

[0052]

[0053]

[0054]

[0055] In the formula, , , For the future , , Predicting speed at any given moment and These are the current time and the previous time respectively. Line number The movement speed of the sub-region, The area of ​​each sub-region, These are the weighting coefficients.

[0056] Step 2: Based on the centroid velocity of the active lightning region, determine the future values ​​corresponding to each active lightning region. , and For the location, direction, and extent of lightning activity, see [link to relevant documentation]. Figure 2 (e);

[0057] Step 3: Quantitatively evaluate the thunderstorm activity forecast results using three indicators: Point of Detection (POD), False Alarm Rate (FAR), and Critical Success Index (CSI).

[0058]

[0059]

[0060]

[0061] In the formula, The number of times a prediction was made correctly. The number of times the report was missed. This refers to the number of times false reporting occurred.

[0062] See the flowchart for constructing early warning areas and early warning indicators for transmission lines. Figure 5 It includes the following steps:

[0063] Step 1: Divide the transmission line early warning area into three levels according to distance, setting them as 2 km, 5 km, and 10 km respectively. class, Level and Level 1 warning area, such as Figure 2 (e);

[0064] Step 2: After real-time monitoring and prediction of the lightning activity area trajectory, it is necessary to determine whether it will pass through the power transmission line warning area;

[0065] Step 3: When the predicted trajectory of the active lightning area intersects with the transmission line, the active lightning area passes through the transmission line area. The estimated time for the active lightning area to reach the transmission line warning area is:

[0066]

[0067]

[0068]

[0069] In the formula, The shortest distance from the boundary of a lightning-active area to a power transmission line, in km; Predicted speeds for areas of high lightning activity, in km / min; , , Reaching the active lightning zone class, Level and The time required for a Level 1 warning area is measured in minutes.

[0070] The embodiments of the present invention are given for the purposes of illustration and description. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Any changes, modifications, substitutions and variations made by those skilled in the art to the above embodiments within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for early warning of lightning paths on transmission lines based on the entire direction of lightning movement and coverage area, characterized in that, Includes the following steps: Step 1: Real-time monitoring algorithm for lightning active areas based on multi-level neighborhood method; Step 2: Predict the active lightning region and movement path of thunderstorm processes that consider the merging and splitting process; Step 3: Construct early warning areas and indicators for transmission lines, and issue early warning signals for transmission lines.

2. The method for early warning of lightning paths on transmission lines based on the entire direction of lightning movement and coverage area as described in claim 1, characterized in that, The real-time monitoring algorithm for lightning active areas based on the multi-level neighborhood method in step 1 includes the following steps: Step 1: Set the time interval The time intervals are integer multiples of 1 minute. Within each time interval, all lightning data are distributed in a geographic grid based on geographic coordinates to form a lightning density map. Step 2: Use the multi-level neighborhood method to divide the lightning activity area within the time interval. First, identify the grid containing lightning events according to the eight-neighbor method to form the primary lightning active area. Then, set the spatial distance threshold according to the distance between the lightning active areas. Lightning active areas less than the threshold are merged to form the final lightning active area. Step 3: Based on the process of merging and splitting of active lightning regions, pair up active lightning regions within consecutive time intervals to form the trajectory of active lightning regions during the thunderstorm process; In the formula, For the predicted speed of movement of lightning active areas, and These represent the movement speeds of each sub-region at the current and previous moments, respectively. The area of ​​each sub-region, This is the weighting coefficient, with a value ranging from 0.5 to 0.8; , These represent the number of rows and columns of the grid, respectively.

3. The method for early warning of lightning paths on transmission lines based on the entire lightning movement direction and coverage area as described in claim 1, characterized in that, Step 2, which considers the merging and splitting process, includes the following steps for predicting the active lightning area and movement path of thunderstorm processes: Step 1: Based on historical speeds and considering merging and splitting, predict the movement speed of lightning activity areas for the next three time intervals as follows: In the formula, , , For the future , , Predicting speed at any given moment and These are the current time and the previous time respectively. Line number The movement speed of the sub-region, The area of ​​each sub-region, These are the weighting coefficients; Step 2: Based on the centroid velocity of the active lightning region, determine the future values ​​corresponding to each active lightning region. , and Location, direction, and extent of lightning activity; Step 3: Quantitatively evaluate the thunderstorm activity forecast results using three indicators: Point of Detection (POD), False Alarm Rate (FAR), and Critical Success Index (CSI). In the formula, The number of times a prediction was made correctly. The number of times the report was missed. This refers to the number of times false reporting occurred.

4. The method for early warning of lightning paths on transmission lines based on the entire direction of lightning movement and coverage area as described in claim 1, characterized in that, Step 3, which involves constructing the early warning area and early warning indicators for transmission lines, includes the following steps: Step 1: Divide the transmission line early warning area into three levels according to distance, setting them as 2 km, 5 km, and 10 km respectively. class, Level and Level 1 warning area; Step 2: After real-time monitoring and prediction of the lightning activity area trajectory, it is necessary to determine whether it will pass through the power transmission line warning area; Step 3: When the predicted trajectory of the active lightning area intersects with the transmission line, the active lightning area passes through the transmission line area. The estimated time for the active lightning area to reach the transmission line warning area is: In the formula, The shortest distance from the boundary of a lightning-active area to a power transmission line, in km; Predicted speeds for areas of high lightning activity, in km / min; , , Reaching the active lightning zone class, Level and The time required for a Level 1 warning area is measured in minutes.

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