KR102110564B1 - Comprehensive disaster prevention system for disaster prevention by occurrence of lightning - Google Patents

Abstract

The present invention relates to a total disaster prevention system for preventing a disaster attributable to lightning. The present invention includes: an earth field meter installed on the top or the outside surface of a building and measuring the electric field in the ground; an earth resistance meter installed so as to penetrate a multi-ground wire without contact with a ground surface and measuring earth resistance; a surge protector installed on a line electrically connecting a power station and an electronic device and protecting the electronic device by absorbing a surge voltage or a surge current flowing in from a commercial power source of the power station in the event of lightning; and a monitoring unit receiving electric field data from the earth field meter, receiving earth resistance data from the earth resistance meter, receiving surge voltage or current data from the surge protector, and determining whether lightning has occurred. In the case of occurrence, the monitoring unit transmits lightning information to one or both of a lightning management server of a management office and an administrator′s mobile communication terminal. According to the present invention, the screens of the office server and the terminal display the lightning information. Accordingly, the administrator can take measures for damage minimization with respect to lightning alarm information depending on the lightning information display status.

Description

A comprehensive disaster prevention system for the prevention of disasters caused by lightning strikes {COMPREHENSIVE DISASTER PREVENTION SYSTEM FOR DISASTER PREVENTION BY OCCURRENCE OF LIGHTNING}

The present invention relates to a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike, and particularly to a comprehensive disaster prevention system that receives and receives data of electric field, ground resistance, surge voltage or surge current in the ground when a lightning strike occurs, and comprehensively prevents it. It is about.

The items described in this background section are written to improve the understanding of the background of the invention, and may include matters other than the prior art already known to those of ordinary skill in the field to which this technology belongs.

In general, thunder or lightning, the most common cause of brain discharge, is thundercloud. These thunderclouds are charged with electricity, and generally the upper part forms ice charges with a positive charge, and the lower part consists of water droplets with a negative charge. As the charge accumulates in the thundercloud, uncharged charges and reverse polarity charges are induced on the surface directly below it, so the electric field strength between the two increases, and when the breakdown of the air insulation exceeds, a spark discharge occurs between the two and a so-called lightning strike occurs. .

When the electric charges gathered in the clouds are discharged to the earth, the electric field strength of the ground also increases. That is, electric charges are collected by a point on the ground by being induced by the electric charge of the lightning. At this time, the more prominent the electric charges can be, so the electric field of the most prominent region rises compared to the surroundings, and the lightning falls there. do.

The places where charges can be easily gathered are trees, people, buildings, etc. on flat ground, especially where dry or metallic material is more likely to gather than those that do not.

Recently, many high-rise buildings have been built, and accordingly, a lightning protection system has been provided to protect buildings from lightning strikes. In particular, the smart home / building to which safety technology is applied is increasing, and the need for an integrated preventive alarm system is increasing. In addition, there is a need to minimize damage from natural disasters.

However, there has not been a comprehensive disaster prevention system through real-time monitoring.

Korean Registered Patent Publication No. 10-1521134

In order to solve the above-described problems of the prior art, the present invention is to display the lightning information on the screen of the lightning management server of the management room and the screen of the mobile communication terminal of the administrator, so that the administrator can use the lightning warning information according to the display state of the lightning information. It is an object of the present invention to provide a comprehensive disaster prevention system for the prevention of disasters caused by lightning strikes that can implement measures to reduce damage to the minimum.

An object of the present invention is to provide a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike that enables a lightning strike to move and measure a high-sensitivity earth field that changes in real time on the ground.

Comprehensive disaster prevention system for preventing a disaster caused by a lightning strike according to an embodiment of the present invention, installed on the top or outer surface of the building, a ground electric field measuring device for measuring the electric field in the ground; A ground resistance meter installed through the multi-ground wire without contacting the ground to measure ground resistance; A surge protector installed on a line electrically connecting the power station and the electronics to protect the electronics by absorbing surge voltage or surge current flowing from the commercial power of the power station when a lightning strike occurs; And receiving electric field data from the earth field meter in real time, receiving ground resistance data from the ground resistance meter in real time, receiving surge voltage or surge current data from the surge protector in real time, and determining whether a lightning strike has occurred. And a monitoring unit that transmits lightning information to at least one of the lightning management server in the management room and the mobile communication terminal of the administrator when a lightning strike occurs.

Here, the earth electric field measuring device measures the electric field in the earth through the amount of charge induced.

In addition, the ground resistance meter is a CT (Current Transformer).

In addition, the monitoring unit stores information on the reference electric field value corresponding to the lightning alarm signal, receives information on the electric field value measured in real time while communicating with the lightning detector, and compares the reference electric field value with the measured electric field value. A lightning alarm that generates a lightning warning signal when the electric field value is higher than; A lightning counter that checks the time at which the lightning alarm generated the lightning alarm signal when a lightning strike occurs, and counts and displays the number of lightning strikes during the period input on the screen; A fire receiving panel displaying an alarm lamp in the fire generating area while an alarm sounds when a fire occurs due to a lightning strike; A lightning protection signal is received from a lightning alarm, and is composed of a body and a lightning rod, but the lightning rod includes a lightning arrester control unit that exposes the lightning rod from the top of the body in a lightning arrestor coupled to the body.

In addition, the body is connected to the hydraulic device, and the lightning device control unit exposes the lightning rod from the top of the body by the hydraulic operation of the hydraulic device when a lightning strike occurs.

In addition, the lightning protection controller operates a timer when a lightning strike occurs, and when the set time has elapsed, receives an operation release signal from the timer to release the operation of the hydraulic device so that the lightning rod is inserted into the upper portion of the body.

In addition, the lightning information includes lightning location information, lightning size, and type of lightning.

According to the present invention, the lightning information is displayed on the screen of the lightning management server of the management room and the screen of the mobile communication terminal of the manager, so that the administrator executes measures to minimize damage to the lightning alarm information according to the display state of the lightning information Can be.

According to the present invention, it is possible to measure the earth electric field changing in real time on the ground with high sensitivity as a lightning strike occurs and moves.

1 is a block diagram of a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a detailed configuration of the monitoring unit of FIG. 1.
Figure 3 is a schematic diagram showing the ground field measurement principle of the earth field meter according to an embodiment of the present invention.
Figure 4 is a schematic diagram showing the grounding resistance measurement principle of the ground resistance meter according to an embodiment of the present invention.
5 is a schematic view before the lightning rod is exposed to the upper portion of the body in a state in which the lightning arrester according to an embodiment of the present invention is connected to the hydraulic system.
Figure 6 is a schematic view after the lightning rod is exposed to the upper portion of the body in the state that the lightning protection device according to an embodiment of the present invention is connected to the hydraulic device.
7 is a flow chart showing a process from the lightning rod signal is generated according to an embodiment of the present invention until the lightning rod is exposed from the top of the body.
8 is a flow chart showing a process until a lightning rod is inserted into an upper portion of a body after a lightning strike according to an embodiment of the present invention.
9 is a time chart showing the operation status of a lightning rod after a lightning strike according to an embodiment of the present invention over time.
10 is a screen of a manager's mobile communication terminal on which lightning information is displayed after a lightning strike according to an embodiment of the present invention.

Advantages and features of the present invention, and a method of achieving them will be apparent with reference to embodiments described below in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. Only embodiments are provided to make the disclosure of the present invention complete, and to fully inform the person of ordinary skill in the art to which the present invention pertains, the scope of the present invention being defined by the scope of the claims. That's it.

1 is a block diagram of a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike according to an embodiment of the present invention.

Referring to FIG. 1, a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike may include a ground electric field meter 100, a ground resistance meter 200, a surge protector 300, and a monitoring unit 400.

The ground electric field measuring device 100 is installed on the top or outside of the building to measure the electric field in the ground. Here, the ground electric field measuring device 100 measures the electric field in the ground through the amount of charge to be induced (field mill method).

The ground resistance meter 200 is installed through the multiple ground wires without contacting the ground to measure ground resistance. The ground resistance meter may be a CT (Current Transformer). This method of measuring ground resistance can be used to measure whether the ground electrode is in good condition.

The surge protector 300 is installed on a line that electrically connects the power station and the electronics to protect the electronics by absorbing surge voltage or surge current flowing from the commercial power of the power station when a lightning strike occurs.

The monitoring unit 400 receives data of the electric field in real time from the earth field meter 100, receives data of the ground resistance from the ground resistance meter 200 in real time, and surge voltage or surge current from the surge protector 300. It receives the data in real time, determines whether a lightning has occurred, and transmits the lightning information to at least one of the lightning management server 10 in the management room and the mobile communication terminal 20 of the manager when a lightning strike occurs.

RS-485 (Recommended Standard 485) method is used as a method for the monitoring unit 400 to receive data from the earth field meter 100, the ground resistance meter 200, and the surge protector 300. RS-485 is an extended version of the existing RS-232 and RS-422 methods and is a kind of serial communication protocol standard that supports home networks. The RS-485 method allows all devices to transmit and receive data on the same line.

The lightning information includes lightning location information, lightning size, and type of lightning. Lightning location information can be represented using direction and distance. The average lightning size is 30kA ~ 40kA, and the lightning size is expressed using kA units. The types of lightning can be classified according to polarity, generation mechanism, and type of lightning. Lightning is classified into positive and negative lightning discharges according to polarity, and classified into heat strikes, lightning strikes, lightning strikes, topographical strikes, and natural lightning strikes according to the mechanism of occurrence. Can be.

On the screen of the lightning management server 10 in the management room and the screen of the administrator's mobile communication terminal 20, lightning information including lightning location information, the size of the lightning, and the type of lightning is displayed. Measures can be implemented to minimize damage to alarm information. The lightning information displayed on the screen of the manager's mobile communication terminal 20 will be described in detail with reference to FIG. 10.

FIG. 2 is a block diagram showing a detailed configuration of the monitoring unit of FIG. 1. Referring to FIGS. 1 and 2, the monitoring unit 400 may include a lightning alarm 410, a lightning counter 420, a fire receiving panel 430 and a lightning protection device control unit 440.

The lightning alarm 410 stores information on the reference electric field value corresponding to the lightning alarm signal, receives information on the electric field value measured in real time while communicating with the lightning detector (not shown), and compares it with the reference electric field value. When the measured electric field value is higher than the reference electric field value, a lightning warning signal is generated.

The reference electric field value is set to a reference lightning predicted electric field value and a reference lightning electric field value, and the lightning warning signal may include a lightning preliminary warning signal and a lightning occurrence alarm signal. At this time, it is preferable that the reference lightning predicted electric field value is about 6 KV / m ² , and the reference lightning electric field value is about 10 KV / m ² to 30 KV / m ² . If the reference electric field value is 15KV / m ² and the measured electric field value is 20KV / m ^{2, a} lightning alarm signal is generated.

The lightning warning signal may be at least one of an alarm sound or a message. By displaying a lightning warning signal or generating an alarm sound on the screen of the lightning management server 10 of the corresponding management room and on the screen of the mobile communication terminal 20 of the manager, the administrator can prevent the damage caused by the lightning as much as possible.

The lightning counter 420 checks the time when the lightning alarm 410 generates a lightning warning signal when a lightning strike occurs, and counts and displays the number of lightning strikes during the period input on the screen.

The fire receiving panel 430 displays an alarm lamp in the fire generating area while an alarm sounds when a lightning strike occurs.

The lightning arrester control unit 440 receives the lightning alarm signal from the lightning alarm 410, and is composed of a body and a lightning rod, but the lightning rod is a lightning rod coupled to the body in a detachable manner, so that the lightning rod is exposed from the top of the body. The operation of controlling the lightning protection device of the lightning protection device control unit 440 will be described in detail with reference to FIGS. 5 and 6.

Figure 3 is a schematic diagram showing the ground field measurement principle of the earth field meter according to an embodiment of the present invention.

Referring to Figure 3, it shows the structure of the earth field meter 100. The ground electric field measuring device 100 includes a base plate 110, a PCB (Printed Curcuit Board, 120), a rotating plate (or rotating conductor, 130), a DC motor 140, a sensing plate 150, a supporting member 160, and a connection It is composed of a member 170.

The DC motor 140 is connected to the rotating plate 130 to receive a drive input from the PCB 120 to rotate the rotating plate 130, which is coupled to the rotating shaft of the DC motor 140 and rotates together with the rotating shaft. , Two or more rotating blades are formed at equal intervals in the circumferential direction with respect to the center.

The sensing plate 150 measures the electric field in the ground through the amount of charge generated while rotating according to the rotation of the rotating plate 130. Such a field electric field measuring method is called a field mill method, and the field mill method allows a high-sensitivity measurement of a ground electric field that changes in real time on the ground due to lightning and moving.

The support member 160 is connected to the base plate 110 and the PCB 120 to support the PCB 120.

The connecting member 170 is connected to the PCB 120 and the rotating plate 130 so that the rotating plate 130 does not deviate from the base plate 110.

Figure 4 is a schematic diagram showing the grounding resistance measurement principle of the ground resistance meter according to an embodiment of the present invention.

Referring to FIG. 4, the ground resistance meter 200 is installed through the multiple ground wires 30 without being in contact with the ground, and shows that the ground resistance is measured. The ground resistance meter 200 is exemplified that a CT (Current Transformer, or a current transformer for an instrument) is used, but is not limited thereto.

For grounding, multiple ground wires 30 are installed, and the instrument panel 40 is connected to the CT 200 installed through the multiple ground wires 30. The CT 200 is a device used to change the magnitude of the current and usually transforms a large current into a low current. The instrument panel 40 is connected to the CT 200 by wire, and the current value is displayed on the instrument panel 40.

FIG. 5 is a schematic view of the lightning rod before being exposed on the upper part of the body in the state where the lightning protection device according to an embodiment of the present invention is connected to the hydraulic device, and FIG. 6 is the lightning protection device according to an embodiment of the present invention connected to the hydraulic device It is a schematic diagram after the lightning rod is exposed to the upper part of the body in the state.

2, 5, and 6, the hydraulic device 50 generates hydraulic pressure by a hydraulic operation, an oil tank that stores hydraulic oil, and a hydraulic pump that is disposed inside the oil tank to suck and discharge hydraulic oil. And, a drive element for driving the hydraulic pump, a control element for controlling at least one of the hydraulic oil discharged from the hydraulic pump and supplied to the actuator, and the hydraulic oil refluxed from the actuator to the oil tank, and the oil tank, drive motor, control A manifold on which the device is mounted may be provided. The hydraulic device 50 is not limited to this as an example, and various modifications are possible.

The lightning protection device 60 is composed of a body 61 and a lightning rod 62, but the lightning rod 62 is detachably coupled to the body 61. The lightning protection device 60 connects the body 61 to the hydraulic device 50 so that when a lightning strike occurs, the lightning rod 62 is exposed from the upper portion of the body 61 by the hydraulic operation of the hydraulic device 50 to protect the lightning current. To release. The body 61 may be installed on the base plate 1 together with the hydraulic device 50. The fact that the lightning rod 62 is inserted into the upper portion of the body 61 means that the lightning current has been returned to the absence of a lightning current.

The lightning protection control unit 440 receives the lightning warning signal from the lightning alarm 410 to operate the hydraulic device 50 so that the lightning rod 62 inserted in the body 61 is exposed from the upper portion of the body 61. At this time, the hydraulic device 50 pushes the lightning rod 62 inserted into the body 61 by the hydraulic operation to the upper portion of the body 61.

A timer (not shown) in the lightning protection device control unit 440 counts the time after a lightning strike has occurred. The lightning arrester control unit 440 operates a timer when a lightning strike occurs and releases the operation of the hydraulic system 50 when the set time has elapsed so that the lightning rod 62 is inserted into the upper portion of the body 61. The set time is set in the timer by the user. For example, the set time may be 30 minutes, but is not limited thereto.

7 is a flow chart showing a process from the lightning rod signal is generated according to an embodiment of the present invention until the lightning rod is exposed from the top of the body.

Referring to FIGS. 1 and 5 to 7, a lightning warning signal is generated to show the process from the upper portion of the body 61 to the exposed portion of the body 61. Let the reference electric field value be 20KV / m ² .

First, the lightning alarm 100 communicates with the lightning detector 10 and receives information about the electric field value measured in real time (S110). The lightning alarm 100 stores information on the reference electric field value 20KV / m ² corresponding to the lightning alarm signal.

After S110, the lightning alarm 100 compares the measured electric field value with a reference electric field value of 20 KV / m ² (S120).

In S120, when the measured electric field value is 20 KV / m ^{2 or} more, the lightning alarm 100 generates a lightning warning signal (S130). However, in S120, when the measured electric field value is less than 20KV / m ² , it feeds back to S110 (feedback).

Apart from S130, the lightning alarm 100 may transmit a lightning warning signal to the administrator's lightning management server 10 and the administrator's mobile communication terminal 20. The lightning warning signal may be at least one of an alarm sound or a message. By displaying a lightning warning signal or generating an alarm sound on the screen of the lightning management server 10 in the management room and on the screen of the manager's mobile communication terminal 20, the administrator can prevent the damage caused by the lightning as much as possible.

In addition, separately from S130, the lightning alarm 100 generates lightning information including lightning location information, lightning size, and lightning type from the measured electric field value, and the lightning management server 10 in the management room and the mobile communication terminal of the administrator ( 20). On the screen of the lightning management server 10 in the management room and the screen of the administrator's mobile communication terminal 20, lightning information including lightning location information, the size of the lightning, and the type of lightning is displayed. Measures can be implemented to minimize damage to alarm information.

After S130, the lightning rod 62 inserted in the body 61 is exposed from the top of the body 61 (S140). At this time, the hydraulic device 50 pushes the lightning rod 62 inserted into the body 61 by the hydraulic operation to the upper portion of the body 61.

8 is a flowchart illustrating a process from the occurrence of a lightning strike according to an embodiment of the present invention until the lightning rod is inserted into the upper portion of the body.

2, 5, 6 and 8, after the lightning strike, the lightning rod 62 shows the process from being inserted into the upper portion of the body 61. For example, suppose that the setting time is 30 minutes.

First, after a lightning strike, the timer operates (S210) to determine whether 30 minutes have passed (S220). The reason for determining whether 30 minutes has elapsed is to release the operation of the hydraulic device 50 so that the lightning rod 62 is inserted into the upper portion of the body 61.

In S220, if 30 minutes have elapsed since the occurrence of a lightning strike, the lightning protection controller 440 releases the operation of the hydraulic device 50 (S230) so that the lightning rod 62 is inserted into the upper portion of the body 61 (S240). The fact that the lightning rod 62 is inserted into the upper portion of the body 61 means that the lightning current has been returned to the absence of a lightning current. In S220, if 30 minutes have not elapsed since the lightning strike, feedback is returned to S210.

9 is a time chart showing the operation status of a lightning rod after a lightning strike according to an embodiment of the present invention over time.

2, 5, 6 and 9, the operation status of the lightning rod 62 according to the time after the lightning strike is shown. For example, suppose that the setting time is 30 minutes.

The lightning arrester control unit 440 operates a timer when a lightning strike occurs, wherein the lightning rod 62 inserted in the body 61 is exposed from the top of the body 61. At this time, the hydraulic device 50 pushes the lightning rod 62 inserted into the body 61 by the hydraulic operation to the upper portion of the body 61.

When 30 minutes have elapsed after the timer operation, the lightning arrester control unit 440 releases the operation of the hydraulic device 50 so that the lightning rod 62 is inserted into the upper portion of the body 61. The fact that the lightning rod 62 is inserted into the upper portion of the body 61 means that the lightning current has been returned to the absence of a lightning current.

10 is a screen of a manager's mobile communication terminal on which lightning information is displayed after a lightning strike according to an embodiment of the present invention.

Referring to FIG. 10, it can be seen that the lightning information including the lightning location information, the lightning size and the lightning type is displayed on the manager's mobile communication terminal.

On the mobile communication terminal of the manager in the management room, lightning information such as "We will inform you of the lightning. A lightning strike with a lightning current of 50 kA occurred 2.5km northwest of the lightning protection device." At this time, it can be seen that the lightning location information is around 2.5 km in the northwest, the lightning current is 50 kA, and the lightning type is a positive polarity lightning discharge.

In addition, a text suggesting a safety measure such as "Please take safety measures by an administrator" was displayed. After checking the screen of the mobile communication terminal, the administrator may execute measures to minimize damage to lightning information on the screen of the mobile communication terminal.

The above-described embodiments of the present invention have been described with reference to the embodiments shown in the drawings to aid understanding, but these are merely exemplary, and various modifications and equivalent other embodiments can be obtained from those skilled in the art. You will understand that it is possible. Therefore, the true technical protection scope of the present invention should be defined by the appended claims.

DESCRIPTION OF SYMBOLS 1 Base plate 10 Lightning management server 20 Mobile communication terminal 30 Multi-grounding line
40: instrument panel 50: hydraulic system
60: lightning arrester 61: body
62: lightning rod 100: earth field meter
110: base plate 120: PCB
130: rotating plate 140: DC motor
141: rotating shaft 150: detecting plate 160: supporting member 170: connecting member 200: ground resistance meter 300: surge protector 400: monitoring unit 410: lightning alarm 420: lightning counter 430: fire receiving panel 440: control unit

Claims (7)

A ground electric field measuring device 100 installed on the top or outside surface of the building to measure the electric field in the ground;
A ground resistance meter 200 installed through the multi-ground wire 30 in a state of not contacting the ground to measure ground resistance;
A surge protector 300 that is installed on a line electrically connecting the power station and the electronic device to protect the electronic device by absorbing surge voltage or surge current flowing from commercial power of the power station when a lightning strike occurs; And
Real-time data of the electric field is received from the earth field meter 100, real-time data of the ground resistance is received from the ground resistance meter 200, and surge voltage or surge current data is received from the surge protector 300. It includes a monitoring unit 400 that receives in real time, determines whether a lightning strike has occurred, and transmits lightning information to at least one of a lightning management server in the management room and a mobile communication terminal of the manager when a lightning strike occurs,
The monitoring unit 400 stores information on a reference electric field value corresponding to a lightning alarm signal, receives information on the electric field value measured in real time while communicating with a lightning detector, and compares the measured electric field value with the reference electric field value. A lightning alarm 410 for generating a lightning warning signal when the calculated electric field value is greater than or equal to the reference electric field value; A lightning counter 420 that checks the time at which the lightning alarm 410 generates a lightning warning signal when a lightning strike occurs, and counts and displays the number of lightning strikes during the period input on the screen; A fire receiving panel 430 displaying an alarm lamp in the fire generating area while an alarm sounds when a fire occurs due to a lightning strike; Lightning alarm signal received from the lightning alarm 410, consisting of a body 61 and a lightning rod 62, but the lightning rod 62 is a lightning protection device that is detachably coupled to the body 61, the lightning rod ( 62) includes an arrester control unit 440 to be exposed from the top of the body 61,
The body 61 is connected to a hydraulic device, and the lightning arrester control unit 440 causes the lightning rod 62 to be exposed from the upper portion of the body 61 by the hydraulic operation of the hydraulic device when a lightning strike occurs,
The lightning protection control unit 440 operates a timer when a lightning strike occurs, and when the set time has elapsed, receives an operation release signal from the timer to release the operation of the hydraulic device, so that the lightning rod 62 of the body 61 Comprehensive disaster prevention system for preventing a disaster caused by a lightning strike, characterized in that it is inserted into the upper part.
According to claim 1,
The reference electric field value is set to a reference lightning predicted electric field value and a reference lightning electric field value, and the lightning alarm signal includes a lightning warning warning signal and a lightning occurrence alarm signal,
The lightning alarm is a comprehensive disaster prevention system for preventing a disaster caused by a lightning strike characterized in that it transmits a lightning warning signal to the mobile communication terminal of the administrator.
According to claim 1,
The earth field measuring instrument 100 is connected between the base plate 110 and the PCB 120 and a support member 160 for supporting the PCB 120,
DC motor 140 which is connected to the rotating plate 130 and receives a driving input from the PCB 120 to rotate the rotating plate 130,
A sensing plate 150 for measuring the electric field in the ground through the amount of charge generated while rotating according to the rotation of the rotating plate 130,
It is connected to the PCB 120 and the rotating plate 130 and includes a connecting member 170 for fixing the rotating plate 130 so as not to be separated from the base plate 110,
The rotating plate 130 is coupled to the rotating shaft of the DC motor 140 and rotates together with the rotating shaft, and two or more rotating blades are formed at equal intervals in the circumferential direction relative to the center of the disaster caused by lightning. Disaster prevention system for prevention.
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