JP2005056279A - Lightning warning device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightning warning device and program capable of issuing an early warning of lightening strokes, sorting thunder clouds by scale, eliminating the need to hold constant the inclinations and sections of line segments into which a line such as a transmission line is divided, and predicting the probability of thunder strokes on the line. <P>SOLUTION: The lightening warning device determines the probability that the line will be struck by lightning on the basis of thunder cloud data showing the positions of thunder clouds and line data showing the length and position of the line, and issues a warning based on the probability. The device comprises a coordinate conversion means 3, a spatial distance calculation means 5, a lightning probability calculation means 7, a lightning probability adding means 9, and a warning canceling means 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lightning strike warning device and a lightning strike warning program for processing data on thunderclouds and tracks and generating warnings.

  Conventionally, as a method for performing lightning warning, for example, a conventional lightning warning method disclosed in Non-Patent Document 1 is a certain point on the ground (observation points by 28 sensors, usually represented by region names). A circle (concentric circle) is drawn at a certain distance from this center point, and when thunderclouds pass through the area within this concentric circle, or the lightning strike indicated by this concentric circle and the actual lightning strike and lightning forecast values. When the area where the probability is high overlaps, the name of the area targeted for lightning warning and the lightning warning level are specified.

  In addition, in the conventional lightning strike warning method, when issuing a warning against lightning based on the relationship between the position of the thundercloud and the position of the transmission line, etc., the dimension of the thundercloud or lightning related data is converted, For example, data conversion using Radon transform (see Tsuneo Saito, “Image Processing Algorithm”, pp104-105, Modern Science, October 1998) or two-dimensional FFT (Hiro Sakamaki et al., “ "High-speed wake detection method using two-dimensional FFT", IEICE Transactions B, Vol. J84-B No. 4 pp785-793, April 2001).

Here, the Radon conversion will be supplementarily described with reference to FIG.
FIG. 10 shows a relationship between a point (x, y) approximating a thundercloud and a line segment (straight line) y = αx + β approximating a line such as a power transmission line. The Radon transform R for this line segment is calculated by the following equation (1) using the line segment inclination α, intercept β, and end point ps as parameters.

  In this equation (1), L is the length of the line segment. Further, a distance d1 of a perpendicular drawn from a point (x, y) approximating a thundercloud to a line segment (straight line) y = αx + β approximating a line such as a power transmission line is calculated by the following equation (2) ( (See Mathematical Handbook for Science and Engineering, p236, Maruzen, October 1989).

  Further, in the conventional lightning warning method, image processing using image data relating to thunderclouds or lightning is performed, and this image processing calculates a horizontal plane image (see Japanese Patent No. 2752142) from image data in the elevation angle direction. Is.

Franklin Japan Co., Ltd., “Outline of JLDN”, [online], [searched July 11, 2003], Internet <URL: http: // www. fjc. co. jp>

  However, since the conventional lightning strike warning method does not grasp the trend of thunderclouds located outside the concentric circles, there is a problem that the warning may be delayed when the thundercloud approaches rapidly.

  Further, when the Radon transform is used for transforming the dimension of the data regarding thunderclouds or lightning strikes, the Radon transform is performed by, for example, a point (thundercloud 1 (x, y)) on a rectangular coordinate (x axis, y axis). When there is a line segment (L, transmission line, etc.), the length of the perpendicular drawn from the point to the line segment is the angle (inclination) between the line segment and the x-axis, and the y-axis obtained by extending the line segment Therefore, it is necessary to keep the slope and intercept of the line segment (transmission line or other line) constant. Similarly, when a two-dimensional FFT is used, it is necessary to make the slope and intercept of a line segment (a line such as a power transmission line) constant.

  Furthermore, in the conventional lightning strike warning method, thunderclouds are regarded as approximate points and warnings are given against lightning strikes, so it is difficult to distinguish between thunderclouds, that is, small thunderclouds and large thunderclouds. There is a problem that.

  Furthermore, the conventional lightning strike warning method is based on a specific point in a certain area. Lightning strikes are applied to linear conductors that are stretched over a wide area such as transmission lines. It is difficult to predict the probability of.

  Therefore, in the present invention, the above-described problems are solved, and even when a thundercloud approaches rapidly, warning against lightning can be issued early, the thundercloud scale can be distinguished, and a line segment obtained by dividing a line such as a transmission line can be distinguished. It is an object of the present invention to provide a lightning strike warning device and a lightning strike warning program capable of predicting the probability of lightning strike on the line without requiring constant inclination and intercept.

  In order to solve the above-mentioned problem, the lightning strike warning device according to claim 1 strikes lightning from the thundercloud to the line based on thundercloud data indicating the position of the thundercloud and line data indicating the length and position of the line. A lightning strike warning device that obtains a probability and issues a warning based on the probability, comprising coordinate conversion means, a spatial distance calculation means, a lightning probability calculation means, a lightning probability addition means, and a warning occurrence cancellation means The configuration.

  According to such a configuration, the lightning strike warning device uses the coordinate conversion unit to generate a thundercloud consisting of a plurality of coordinates that are included in the thundercloud data and identify the position of the thundercloud based on the line data. The intersection of the straight line drawn from the spatial coordinates toward each line segment approximating a plurality of straight lines and the line segment is obtained as a reference point. The track data relates to tracks including power transmission lines, railway tracks, etc. (conductors stretched over the surface of the earth, or tracks that are not visible, such as air and sea routes, tracks other than conductors), and the length of the track (m ), The position (x, y, z) on the ground surface of the track. Each line segment is obtained by approximating a line to a straight line and dividing the line by an arbitrary number of times (at least 1 or more) until the length of the straight line reaches a predetermined length. Furthermore, thundercloud data is information observed by the Japan Meteorological Agency radar and includes the thundercloud shape, thundercloud total volume (thundercloud scale), thundercloud movement direction, thundercloud movement speed, etc., and the exact location of the thundercloud. The thundercloud spatial coordinates (x, y, z) indicating Incidentally, thunderclouds and rain clouds can be identified because the ascending air current of thunderclouds is higher than that of rain clouds based on information observed by the Japan Meteorological Agency radar. As an example, among rain clouds observed by the Japan Meteorological Agency radar, thunderclouds having a rainfall amount of 4 mm / h or more and a cloud top height data of 8 km or more are used. In addition, the shape of the thundercloud is determined from the thundercloud spatial coordinates, and the boundary between the thundercloud and the atmosphere around the thundercloud is defined. For example, the Japan Meteorological Agency radar is distributed in mesh units (two-dimensional squares), and thunderclouds are defined using these mesh units. Furthermore, when considering the line as a straight line from the line data (straightening), for example, taking a transmission line as an example, as an example, the start point is a substation, the end point is a broadcasting station, and the start point or the end point is linearized. .

  Subsequently, in this lightning strike warning device, the spatial distance calculation means calculates the spatial distance between the thundercloud and each line segment of the track based on the reference point obtained by the coordinate conversion means and the spatial coordinates of the thundercloud. For example, when the track is a power transmission line, the spatial distance is a distance of a straight line connecting a reference point of each line segment of the power transmission line and each point (spatial coordinates (x, y, z)). The distance of the straight line is obtained by taking the difference of each component between the coordinate indicating the reference point and the space coordinate and squaring, and obtaining the square root of the sum of the squares.

  Then, the lightning strike warning device uses the lightning probability calculating means as a random variable for the spatial distance calculated by the spatial distance calculating means, and each line segment based on the probability density distribution calculated in advance for the relationship between the spatial distance and the lightning probability. The probability of lightning strike is calculated, and the lightning strike probability adding means calculates the lightning strike probability of each line segment as the total lightning strike probability added in units of lines. The probability density distribution is obtained by calculating in advance the relationship between the spatial distance, which is the distance of a straight line connecting the spatial coordinates of the thundercloud and the reference point of the track, and the probability of a lightning strike. That is, it is assumed that the probability of a lightning strike from the thundercloud increases or decreases depending on the distance between the track and the thundercloud. The lightning strike probability adding means adds the lightning strike probability obtained for each line segment for each line, and obtains the total lightning strike probability that is the lightning strike probability for each line.

  The lightning strike warning device outputs a warning occurrence signal when the total lightning probability added by the lightning probability addition means is equal to or higher than a preset threshold by the warning occurrence release means, and outputs a warning release signal when it is less than the threshold. Is output. That is, by changing the threshold value, it is possible to set a lightning warning level that prompts a countermeasure such as refraining from going out to prevent a disaster caused by lightning.

  The lightning strike warning device according to claim 2 is the lightning strike warning device according to claim 1, wherein the thundercloud data is calculated based on data measured in advance, and it is assumed that lightning strikes occur from each of the thunderclouds. A thundercloud actual value indicating the current value of the lightning strike probability, and a thundercloud predicted value indicating a predicted value of the lightning probability when it is assumed that a lightning strike occurs from each of the thunderclouds, calculated based on previously measured data. It is characterized by being.

  According to this configuration, the lightning strike warning device includes the thundercloud actual value and the thundercloud predicted value in the thundercloud data. More specifically, the thundercloud actual value is data observed by the Meteorological Agency radar, The predicted value is data obtained by performing prediction processing on data observed by the Meteorological Agency radar. For example, a homepage on the Internet (http://www.jwa.or.jp/b/kisho_info/index.html, Japan Meteorological Association) , As of August 6, 2003). The “National Lightning Information” on this website is applicable.

  The lightning strike warning device according to claim 3 is the lightning strike warning device according to claim 1 or 2, wherein the lightning strike warning device according to claim 3 is based on the speed of movement of the thundercloud included in the thundercloud data. Threshold value setting means for setting the threshold value so that the threshold value decreases by a certain value is provided.

  According to this configuration, the lightning strike warning device sets the threshold based on the thundercloud moving speed by the threshold setting means. For example, when the thundercloud moving speed is 30 km / h, the threshold is set to 16.16. When the speed is 60 km / h, the threshold is set to 13.24.

  The lightning strike warning program according to claim 4 is based on thundercloud data indicating the position of thunderclouds and line data indicating the length and position of a line that is a conductor stretched on the ground surface. In order to obtain the probability of lightning strike and issue a warning based on this probability, the computer functions as a coordinate conversion means, a spatial distance calculation means, a lightning probability calculation means, a lightning probability addition means, a warning occurrence cancellation means, and did.

  According to such a configuration, the lightning strike warning program includes a plurality of line segments that are included in the thundercloud data and that specify the position of the thundercloud based on the line data. The intersection of the straight line drawn from the spatial coordinates of the thundercloud consisting of coordinates toward each line segment and the line segment is obtained as a reference point, and the reference point obtained by the coordinate conversion means and the spatial coordinates of the thundercloud are obtained by the spatial distance calculation means. Based on this, the spatial distance between the thundercloud and each line segment of the track is calculated. And this lightning strike warning program calculates the probability of lightning strike in each line segment from the probability density distribution with the spatial distance calculated by the spatial distance calculation means as a random variable by the lightning probability calculation means, and calculated by the lightning probability addition means. The lightning strike probability in each line segment is defined as the total lightning strike probability added in units of lines. Furthermore, the lightning strike warning program outputs a warning occurrence signal when the total lightning probability added by the lightning probability addition means is equal to or higher than a preset threshold by the warning occurrence release means, and also outputs a warning release signal when it is less than the threshold. Is output.

  According to the first and fourth aspects of the present invention, even when a thundercloud approaches rapidly, a warning against lightning strikes early based on the spatial distance from the thundercloud by a large number of reference points where the track is stretched. It is possible to predict the probability of a lightning strike on the line without having to make the slope and intercept of the line segment obtained by dividing the line such as a transmission line constant.

  The invention according to claim 2 can issue a lightning warning in consideration of the scale of the thundercloud based on the thundercloud actual value and the thundercloud prediction value.

  The invention according to claim 3 issues warning against lightning early, even if the thundercloud approaches rapidly, by setting a threshold value as a reference for issuing warning against lightning based on the moving speed of the thundercloud. Can do.

Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.
(Configuration of lightning warning device)
FIG. 1 is a block diagram of a lightning warning device. As shown in FIG. 1, a lightning strike warning device 1 receives transmission line data (line data) and thundercloud data, and issues a warning against a lightning strike intended for the transmission line (a warning occurrence signal and a warning release signal). Output coordinates), coordinate conversion means 3, spatial distance calculation means 5, lightning probability calculation means 7, lightning probability addition means 9, and warning occurrence cancellation means 11.

  The transmission line data includes the transmission line length (m), the position on the ground plane, and the ground surface, with the length (m) between the power poles as the minimum unit for each fixed range where the transmission line is stretched. And the position (spatial coordinates) of the power transmission line including the height of the power transmission line hung on the power pole that changes due to the unevenness.

  The thundercloud data includes a thundercloud position (spatial coordinates), a scale, a moving direction (east, west, north and south, etc.), a moving speed (speed), a thundercloud actual value, a thundercloud predicted value, and the like. More specifically, the thundercloud actual value is data observed by the Japan Meteorological Agency radar, and the thundercloud predicted value is data obtained by performing prediction processing on the data observed by the Japan Meteorological Agency radar. Moreover, instead of this thundercloud actual value and thundercloud predicted value, a thunderstorm actual value and a thundercloud predicted value can also be included. The actual lightning strike value is the data provided by TEPCO El Passo, and the predicted lightning strike value is the data provided by TEPCO's rainfall / lightning observation information that has undergone prediction processing (Tokyo Electric Power's website address on the Internet). Is http://www0.thunder.ne.jp/ (as of August 6, 2003)). The thundercloud's spatial coordinates can identify the thundercloud's position, and the thundercloud's scale can be considered to be larger as the number of thundercloud's spatial coordinates increases, and conversely, the thundercloud's spatial coordinates. The smaller the number, the smaller the scale.

  The coordinate conversion means 3 is a straight line consisting of a plurality of straight lines, which is hung by a large number of power poles or the like located at a certain height from the ground surface and complicatedly extended based on the input power line data. It is regarded as a group, and each straight line included in this straight line group is decomposed into a plurality of line segments, and the reference point of this line segment is obtained. That is, in this coordinate conversion means 3, first, the transmission line stretched around like a mesh is divided into line segments (a plurality of line segments) that can be approximated to a straight line. The intersection between the straight line (perpendicular line) drawn from the spatial coordinates (x, y, z) of the thundercloud included in the thundercloud data and each line segment is used as a reference point. That is, the reference point is a spatial coordinate (x ′, y ′, z ′) that serves as a reference for calculating the distance between the line segment and the thundercloud. In this embodiment, a perpendicular line is drawn for each line segment from each of the thundercloud spatial coordinates, and the intersection of each perpendicular line and each line segment is used as a reference point.

  For example, a transmission line from a certain point a to a certain point b (a transmission line in which a section between a certain point a and a certain point b is refracted in a complicated manner) is linearly connected between a certain point a and a certain point b within an allowable error. Is divided into line segments for each length that can be approximated to, and a section between a point a and a point b is approximated by a plurality of line segments. The length of the approximated line segment depends on the allowable error, and the relationship between the allowable error and the length of the line segment will be described later. As a more specific example, a transmission line of about 10 m obtained by equally dividing a transmission line of a section of about 100 m into 10 equal parts is regarded as one line segment. The coordinate conversion means 3 obtains reference points on the line segment for all thunderclouds observed by the Japan Meteorological Agency radar. The next spatial distance calculation means 5 and the lightning strike probability calculation means 7 always use the line segment. Since the probability of lightning strikes is calculated for each, even if the moving speed of thunderclouds increases rapidly, warning against lightning strikes can be issued early.

  The spatial distance calculation means 5 calculates the spatial distance by the coordinate conversion means 3 based on the spatial coordinates of the reference points of the divided line segments and the thundercloud position (spatial coordinates) included in the thundercloud data. Is.

Here, how to calculate the spatial distance will be described with reference to FIGS.
2 and 3 show an embodiment for calculating the spatial distance. As shown in FIG. 2, a thundercloud 1 (X ₁ , Y ₁ ) whose position is specified by thundercloud data and a line segment 1 (straight line y = line) divided by the coordinate conversion means 3 based on the transmission line data. The distance d _{1 from} (part of αx + β) is calculated by the equation (2) described in the section of the prior art.

Then, as shown in FIG. 3, the distance d ₁ calculated by the formula (2) is set as the shortest distance, and the line segment 1 is calculated from the intersection of the perpendicular lines drawn from the thundercloud 1 (X ₁ , Y ₁ ) to the line segment 1. the distance l ₁ to the midpoint, thundercloud ₂ (X 2, Y 2) and the straight line distance d ₂ by subtracting the end point of the line segment 1 from an extension of the line 1 from the thundercloud ₂ (X 2, Y 2) A distance l ₂ from the intersection of the drawn perpendicular lines to the midpoint of the line segment 1 is used, and a spatial distance is calculated by performing a correction using these distances.

  In FIG. 3, in this embodiment, the length of the line segment is L, and the point where the perpendicular drawn from the thundercloud 1 intersects with the line segment 1 (reference point) is a. The spatial distance is calculated by dividing the processing range of 1 into a range of a ≦ L (range 1) and a range of a ≧ L (range 2).

In FIG. 3, in the range of a ≦ L, when the distance l ₁ from the point P (reference point) where the perpendicular drawn from the thundercloud 1 intersects the line segment 1 to the midpoint of the line segment 1 is, the spatial distance dmn is It is calculated by the following equation (3). Note that the subscript _mn of the spatial distance d _mn corresponds to the subscript attached to each line segment.

In Equation (3), k ₁ is a coefficient for correction.

In FIG. 3, in the range of a ≧ L, if the distance l ₂ from the point where the perpendicular drawn from the thundercloud 2 intersects on the extension of the line segment 1 to the midpoint of the line segment 1 is, the spatial distance d _mn is , Calculated by the following equation (4).

In this formula (4), the distance d ₂ of the straight line is calculated by the following formula (5).

図１に戻って説明を続ける。
落雷確率算出手段７は、空間距離算出手段５で算出された空間距離を確率変数とした確率密度分布から各線分における落雷の確率を算出するものである。この実施の形態では、確率密度分布（確率密度関数）として、いわゆる正規分布を使用している。また、落雷の確率は、確率変数とした空間距離が小さくなればなるほど、つまり、導体を含んで構成されている送電線と雷雲との距離が短くなればなるほど、高くなる傾向にある。

Returning to FIG. 1, the description will be continued.
The lightning strike probability calculating means 7 calculates the probability of lightning strikes in each line segment from the probability density distribution using the spatial distance calculated by the spatial distance calculating means 5 as a random variable. In this embodiment, a so-called normal distribution is used as the probability density distribution (probability density function). In addition, the probability of lightning strikes tends to increase as the spatial distance as a random variable decreases, that is, as the distance between a transmission line including a conductor and a thundercloud decreases.

Here, with reference to FIG. 4, a method for calculating the lightning strike probability will be described.
FIG. 4 shows the relationship between the spatial distance and the degree of lightning strike (probability). As shown in FIG. 4, when the lightning probability density function is a normal distribution and the spatial distance d _mn is a random variable, the lightning probability P _mn is calculated by the following equation (6).

That is, on the probability density function, the degree of lightning strike corresponding to the spatial distance d ₁₂ is the lightning strike probability P ₁₂ (line segment 1), and the degree of lightning strike corresponding to the spatial distance d ₁₁ is the lightning strike probability P ₁₁ . (Line segment 1), the degree of lightning strike corresponding to the spatial distance d ₂₁ is the lightning probability P ₂₁ (line segment 2), and the degree of lightning strike corresponding to the spatial distance d ₂₂ is the lightning probability P ₂₂ ( Line 2). In addition, when the top height data of thundercloud is 8km to 13km, it is a low level thundercloud, and when the top height data of thundercloud is 14km, the thundercloud is a high level, and the lightning generated from the low level thundercloud is a weak thundercloud. The lightning generated from the thundercloud is defined as a strong lightning, the coefficient of lightning is 0.5, the coefficient of lightning is 1, and the probability of lightning P _mn in equation (6) is multiplied by this coefficient to obtain a line from each thundercloud. The probability of a lightning strike to the minute.

The lightning strike probability adding means 9 calculates a total lightning strike probability by adding the lightning strike probability P _mn obtained for each line segment in units of transmission lines. That is, the lightning probability P _mn is subjected to the following addition process to calculate the total lightning probability. In this embodiment, the lightning strike probability addition processing for each line segment is performed by assuming the simultaneous probability that lightning strikes from each thundercloud to each line segment as an independent event at an arbitrary time, using the following formulas (7), ( 8) (Hisao Ogura, “Introduction to Stochastic Process”, pp14-pp15, pp192, Morikita Publishing, November 1998).

なお、この数式（８）は、Ｐａｒｓｅｖａｌの等式である。

The equation (8) is a Parsval equation.

Since the lightning strike probabilities P _mn (x ₁ ), P _mn (x ₂ ),..., P _mn (x _N ) obtained in Expression (7) are constants at an arbitrary time, Expression (8 ), A _n and b _n are 0. Therefore, the simultaneous probability of a lightning strike to a line segment due to a thundercloud at an arbitrary time is calculated by the following equation (9).

この実施の形態では、数式（９）の分母の定数２の代わり係数ｋ₂を用いると共に、雷雲の個数を対数に変換する次の数式（１０）を使用して各線分の落雷の確率を算出している。

In this embodiment, the coefficient k ₂ is used in place of the constant 2 of the denominator of the formula (9), and the lightning probability of each line segment is calculated using the following formula (10) that converts the number of thunderclouds to a logarithm. doing.

また、この実施の形態では、各送電線への落雷の確率Ｐ_total（合計落雷確率）は、各線分の落雷の確率Ｐ_mnを単純に加算する次の数式（１１）によって算出される。

In this embodiment, the lightning strike probability P _total (total lightning strike probability) to each power transmission line is calculated by the following formula (11) that simply adds the lightning strike probability P _mn of each line _segment .

Returning to FIG. 1, the description will be continued.
The warning occurrence canceling means 11 outputs a warning occurrence signal and outputs a total lightning probability (when the total lightning probability (P _total ) obtained by the lightning probability adding means 9 exceeds a preset threshold value (warning value). When _Ptotal ) is less than the threshold value, a warning release signal is output. These processes are referred to as a warning value setting process. Further, the warning occurrence canceling means 11 includes a threshold setting means 11a for setting a threshold based on the moving speed of the thundercloud included in the thundercloud data. The threshold setting means 11a sets the threshold low when the thundercloud moving speed increases, and sets the threshold high when the thundercloud moving speed decreases. That is, the threshold setting unit 11a increases or decreases the threshold in proportion to the moving speed of the thundercloud.

Here, a warning value setting process will be described with reference to FIG.
FIG. 5 (a) schematically shows a thundercloud moving over the surface of the earth, and FIG. 5 (b) assumes a case where the thundercloud is approaching and is located at substantially the center where the transmission line is divided. This indicates that a warning value (threshold value, approximately 13.24 in FIG. 5B) is set based on the probability of lightning strike (total lightning strike probability) 15 minutes before reaching the line segment. The axis represents the probability of lightning strikes (total lightning probability (P _total )), and the horizontal axis represents the time before the thundercloud arrived and the time after the thundercloud passed, with the time when the thundercloud reached directly above the transmission line as 0. Represents.

That is, the lightning strike probability P _m1, which is the probability of a lightning strike from one thundercloud to the line segment m, is calculated according to the following equation (12) using equations (6) to (10).

  Further, the lightning strike probability P warning, which is the probability of lightning strikes from one thundercloud to the transmission line, is calculated by the following equation (13) based on the result of the equation (12).

According to this lightning warning device 1, the coordinate conversion means 3 subtracts the line segment obtained by dividing the transmission line (track) from the spatial coordinates of the thundercloud included in the thundercloud data based on the transmission line data (line data). The intersection of the perpendicular and each line segment is obtained as a reference point. Subsequently, the spatial distance calculation means 5 calculates the spatial distance between the thundercloud and each line segment of the track based on the reference point obtained by the coordinate conversion means 3 and the spatial coordinates of the thundercloud included in the thundercloud data. The Then, the lightning strike probability calculating means 7 calculates the lightning probability P _mn in each line segment from the probability density distribution using the spatial distance calculated by the spatial distance calculating means 5 as a random variable, and the lightning probability adding means 9 calculates each line calculated. The probability P _mn of lightning strikes per minute is taken as the total lightning strike probability P _total added in units of transmission lines (tracks).

When the total lightning probability P _total added by the lightning probability adding means 9 is greater than or equal to a preset threshold value (warning value) by the warning occurrence canceling means 11, a warning occurrence signal is output and the threshold value (warning value) If it is less than, a warning release signal is output. For this reason, by extending a certain point on the ground, which was the object of lightning warning, to a line such as a power transmission line, the lightning warning range covers a wide area on the surface, and thunderclouds rapidly Even when approaching, warning against lightning can be issued early.

  In addition, by calculating the spatial distance, which is the distance between each line segment obtained by dividing the transmission line and each thundercloud, for each thundercloud, the probability of lightning strikes increases or decreases. In other words, when the thundercloud scale increases, it is considered that the thundercloud quantity has increased, and conversely, when the thundercloud scale decreases, it is considered that the thundercloud quantity has decreased. As a result, the increase or decrease of can contribute to the discrimination of thundercloud scale.

  Further, depending on how the spatial distance is calculated by the spatial distance calculation means 5, there is no need to make the slope and intercept of the line segment obtained by dividing the transmission line or the like constant, and the lightning strike probability is predicted for the line. can do.

  Further, according to the lightning strike warning device 1, the thundercloud data includes a thundercloud actual value indicating a thundercloud scale and a moving direction, and a thundercloud predicted value indicating a thundercloud scale and a moving direction after a predetermined time. More accurate lightning strike probability can be calculated.

  Further, according to the lightning strike warning device 1, the threshold value changing unit 11a of the warning occurrence canceling unit 11 changes the threshold based on the moving speed of the thundercloud, and refrains from going out in order to prevent a disaster caused by a lightning strike. It is possible to change the lightning warning level that prompts to deal with the situation.

(Operation of lightning warning device)
Next, the operation of the lightning warning device 1 will be described with reference to the flowchart shown in FIG. 6 (see FIG. 1 as appropriate). The operation of the lightning strike warning device 1 describes a series of processes when power line data is input in advance to the lightning strike warning device 1 and thundercloud data that changes every moment is inputted.
First, the lightning strike warning device 1 uses the coordinate conversion means 3 to make the transmission line a plurality of line segments based on the transmission line data, and based on the thundercloud spatial coordinates of the thundercloud data, Conversion) is obtained (step S1).

Subsequently, the lightning strike warning device 1 calculates the spatial distance by the spatial distance calculation means 5 based on the reference point on each line segment and the spatial coordinates of the thundercloud of the thundercloud data (step S2). Here, the spatial distance is obtained by the number of thundercloud spatial coordinates included in the thundercloud data. Then, the lightning strike warning device 1 uses the lightning strike probability calculating means 7 to calculate the lightning strike probability P _mn of each line _segment using each spatial distance as a random variable (step S3).

Then, the lightning strike warning device 1 obtains the total lightning probability P _total by adding the lightning probability P _mn of each line _segment in units of transmission lines by the lightning probability adding means 9 (step S4). Then, the lightning strike warning device 1 determines whether or not the total lightning strike probability P _total that is the lightning strike probability with respect to the transmission line is equal to or higher than a preset threshold value (warning value) by the warning occurrence canceling means 11 (step S5).

Here, when it is determined that the total lightning strike probability P _total is equal to or greater than a preset threshold value (warning value) (step S5, Yes), the lightning strike warning device 1 outputs a warning signal to the outside (step). S6). Moreover, when it is not determined in step S5 that the total lightning strike probability _Ptotal is equal to or higher than a preset threshold value (warning value) (step S5, No), the warning occurrence signal is currently the lightning warning device 1 concerned. It is determined whether or not it is output from (step S7). When it is determined that the warning occurrence signal is output from the lightning strike warning device 1 (step S7, Yes), the lightning strike warning device 1 outputs a warning release signal to the outside (step S8).

  If it is not determined in step S7 that a warning signal has been output from the lightning warning device 1 (No in step S7), whether or not new thundercloud data has been input to the lightning warning device 1. If it is determined (step S9) and it is determined that it has been input (step S9, Yes), the process returns to step S2, and if it is not determined that it has been input (step S9, No), the operation is terminated.

(Supplement, how to approximate the transmission line to the line segment, the distance between the transmission line and thundercloud)
Next, a method for approximating a power transmission line to a line segment and a distance between the power transmission line and a thundercloud will be described with reference to FIG. FIG. 7A shows an error in the case of dividing (approximate) a complicatedly extended power transmission line into each line segment. In FIG. 7A, the distance from the thundercloud to the line segment is d, and the distance from the thundercloud to the power transmission line is d + Δd. If the allowable error is er, Δd is calculated by the following equation (14).

また、この数式（１４）において、Ｐｂ（ｑ）は次の数式（１５）によって算出される。

Further, in this equation (14), Pb (q) is calculated by the following equation (15).

  When the allowable error er is given by these mathematical formulas (14) and (15), Δd is calculated by the following mathematical formula (16).

  FIG. 7B shows the relationship between the transmission line and the degree of lightning strike (probability), the horizontal axis represents the distance between the transmission line and thundercloud, and the vertical axis represents the degree of lightning strike (probability). Yes.

  FIG. 7C shows the relationship between the transmission line and the approximation error, the horizontal axis represents the distance between the transmission line and the thundercloud, and the vertical axis represents the approximation error value. Further, in FIG. 7C, curves with an error of 50%, 40%, 30%, 20%, 10%, 5%, and 0.5% are shown from above.

(About the output result output from the lightning warning device)
Next, with reference to FIG. 8, an output result (screen displayed on a display device not shown) output from the lightning warning device 1 will be described (see FIG. 1 as appropriate). FIG. 8 shows an example of a display screen displayed on a display device (not shown).

  In the output result (display screen), the lightning strike degree (probability) calculated by the lightning strike probability adding means 9 of the lightning strike warning device 1 is displayed in a time-series line graph, and the spatial distance calculating means of the device 1 is displayed. The distance (spatial distance) between the transmission line and thundercloud calculated in 5 is displayed in a time-series line graph, and the change in thundercloud movement speed and direction (change in situation) can be confirmed visually. Has been.

  In addition, in this output result (display screen), a certain threshold (warning value) is set for the degree of lightning strike (probability), and the current situation is ranked as "normal", "caution", "warning" They are displayed separately. In this case, there are two threshold values set by the threshold value setting means 11a of the warning occurrence canceling means 11, and these two threshold values are a first threshold value at which a warning occurrence signal is output at the “caution” stage, and “ And a second threshold value at which a warning signal is output at the stage of “warning”. When the lightning strike probability exceeds the “warning” rank, an alarm sound is output from a speaker (not shown) and notified.

  Furthermore, in this output result (display screen), the movement of thunderclouds around the observation area observed by the Japan Meteorological Agency radar from the past one week to the present is accumulated in the accumulation means (not shown) on the drawn map. Display and monitor thundercloud movement.

(About remarkable effect of lightning warning device)
Next, with reference to FIG. 9, the remarkable effect of the lightning warning device 1 will be described.
FIG. 9 shows in advance a personal generator in advance when a lightning strike occurs due to a lightning strike when a lightning strike is guarded by the conventional method and when a lightning strike is alerted by this method (lightning strike warning device 1). This shows the operation time when operating the generator, the time from the start of the private generator to the power failure, and the time from the power failure to the generator stop.

In this case, for setting the threshold value (warning value), an approximation error obtained by approximating the power transmission line with a line segment is set to 2 km from the power transmission line in both directions. As the coefficients, k ₁ is 100, σ is 10, and k ₂ is 3.1. Further, assuming that a private power generator is operated in advance assuming a power failure, it is set that an operator who operates the private power generator takes 10 minutes to operate the private power generator. Furthermore, the conventional method sets 30 km in both directions from the transmission line as a warning frame. As input data, thundercloud data and cloud top height data with a rainfall amount of 4 mm / h or more acquired from the Meteorological Agency radar were used.

  As shown in FIG. 9, when the conventional method and this method are compared, the operation time of the private generator is reduced by an average of 5 hours. In other words, in the conventional method, there is a possibility that the warning will be delayed for a lightning lightning that approaches rapidly, and it was difficult to distinguish the thundercloud scale, whereas in this method, the thundercloud that approaches rapidly It is possible to accurately alert to lightning strikes, and to alert early on the arrival of large-scale thunderclouds (attack) compared to the arrival (attack) of small-scale thunderclouds. .

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment. For example, the processing of each component of the lightning warning device 1 can be regarded as a lightning warning program described in a general-purpose computer language. In this case, the same effect as that of the lightning warning device 1 can be obtained.

  In addition, instead of thundercloud data input to the lightning strike warning device 1, it is possible to input raincloud data including the moving direction and speed of the raincloud, or to input flowering prediction data that predicts cherry blossoms. It can also be used as a warning device or a flowering prediction device.

It is a block diagram of the lightning warning device which concerns on embodiment. It is a figure explaining how to calculate the spatial distance. It is a figure explaining how to calculate a spatial distance (a line segment is shown horizontally). It is the figure which showed the relationship between spatial distance and the degree (probability) of a lightning strike. (A) is a figure which shows typically the thundercloud which moves over the sky on the surface of the earth, and (b) is a figure which shows setting a warning value on the assumption that the thundercloud approaches. It is the flowchart explaining operation | movement of the lightning strike warning device shown in FIG. (A) is the figure which showed the error at the time of dividing | segmenting (approximate) the power transmission line extended in complexity, (b) showed the relationship between a power transmission line and the degree (probability) of a lightning strike. (C) is the figure which showed the relationship between a power transmission line and an approximation error. It is the figure which showed the output result output from the lightning strike warning device shown in FIG. It is the figure which showed the operation time, the time from the start to the power failure, and the time from the power failure to the stop, when the lightning is warned by the conventional method and when the lightning is warned by this method (lightning warning device). . It is a figure explaining the conventional radon conversion.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lightning strike warning device 3 Coordinate conversion means 5 Spatial distance calculation means 7 Lightning strike probability calculation means 9 Lightning strike probability addition means 11 Warning occurrence cancellation means 11a Threshold setting means

Claims (4)

Based on thundercloud data indicating the position of the thundercloud and line data indicating the length and position of the track, a lightning strike warning device that obtains a probability of lightning from the thundercloud to the track and issues a warning based on the probability. ,
Based on the track data, straight lines that are included in the thundercloud data and are drawn toward each line segment that approximates the lines from a thundercloud spatial coordinate that includes a plurality of coordinates that specify the position of the thundercloud. , Coordinate conversion means for obtaining the intersection with each line segment as a reference point;
Based on the reference point obtained by the coordinate conversion means and the spatial coordinates of the thundercloud, a spatial distance calculation means for calculating a spatial distance between the thundercloud and a reference point of each line segment of the line,
The lightning probability calculation means for calculating the lightning probability in each line segment based on a probability density distribution in which the spatial distance calculated by the spatial distance calculation means is a random variable and the relationship between the spatial distance and the lightning probability is calculated in advance. ,
Lightning probability addition means for setting the lightning probability in each line segment calculated by the lightning probability calculation means as a total lightning probability added for each line,
A warning occurrence cancellation means for outputting a warning occurrence signal when the total lightning probability added by the lightning probability addition means is equal to or higher than a preset threshold value, and outputting a warning release signal when the total lightning probability is less than the threshold value;
A lightning warning device characterized by comprising:   The thundercloud data was calculated based on pre-measured data calculated based on pre-measured data, the thundercloud actual value indicating the current value of the probability of lightning strikes assuming that lightning strikes occur from each of the thunderclouds. The thundercloud warning device according to claim 1, further comprising a thundercloud predicted value indicating a predicted value of the probability of a thunderbolt when it is assumed that a thundercloud occurs from each of the thunderclouds.   The apparatus further comprises threshold setting means for setting the threshold so that the threshold decreases by a constant value every time the moving speed increases by a constant speed based on a moving speed of the thundercloud included in the thundercloud data. A lightning strike warning device according to claim 1 or 2. Based on thundercloud data indicating the position of the thundercloud and line data indicating the length and position of the track, a computer is used to determine the probability of lightning from the thundercloud to the track, and to issue a warning based on this probability.
Based on the track data, straight lines that are included in the thundercloud data and are drawn toward each line segment that approximates the lines from a thundercloud spatial coordinate that includes a plurality of coordinates that specify the position of the thundercloud. , A coordinate conversion means for obtaining an intersection with the line segment as a reference point;
Based on the reference point obtained by the coordinate conversion means and the spatial coordinates of the thundercloud, a spatial distance calculation means for calculating a spatial distance between the thundercloud and a reference point of each line segment of the line,
The lightning probability calculation means for calculating the lightning probability in each line segment based on a probability density distribution in which the spatial distance calculated by the spatial distance calculation means is a random variable, and the relationship between the spatial distance and the lightning probability is calculated in advance.
Lightning probability addition means for setting the lightning strike probability in each line segment calculated by the lightning probability calculation means to be the total lightning probability added for each line,
A warning occurrence cancellation means for outputting a warning occurrence signal when the total lightning probability added by the lightning probability addition means is equal to or higher than a preset threshold value, and outputting a warning release signal when the total lightning probability is less than the threshold value,
Lightning warning program characterized by functioning as

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