JP2008096336A - Simple detector of surge current - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple detector of surge current capable of detecting a location of a lightning strike on a main line of a power transmission line, regardless of the presence or absence of a fault on the power transmission line. <P>SOLUTION: A detector 5 connected to a surge current sensor 4 detects and controls information on the level, the propagation direction and the time of a surge current based on the surge current, and transmits each information by radio. The detector 5 is driven by a solar battery or a primary battery when a control part 9 and a transmission part 10 are actuated by the surge current. Information transmitted from the detector 5 is determined for a lightning location by a central unit provided in the ground section based on the information. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a simple surge current detector for detecting a lightning strike location by detecting a surge current generated in a power line of an overhead power transmission line due to a lightning strike or the like.

As a method for detecting a surge current generated in an overhead power transmission line due to a lightning strike or the like and grasping a failure point, there is a surge reception system disclosed in Patent Document 1.
This method detects the surge wave at the time of failure occurrence at both ends of the transmission line, detects the reception time, and uses the fact that the difference in reception time at both ends matches the propagation time difference of the surge to locate the failure point. is there.
JP-A-8-62277

  However, in the conventional surge reception system, in order to obtain the propagation time difference, a highly accurate time management is required and the apparatus power is generally large. In addition, surge reception is generally performed on an overhead ground wire, and the transmission is also performed using a wire such as an optical fiber. For this reason, when lightning strikes on the main line, those that do not respond to lightning strikes that do not lead to an accident are common.

  In addition, a CT (transformer) is generally used as a sensor for receiving a surge current. However, since a magnetic core is required, the problem is that the CT generates heat due to magnetic loss in the high frequency region, and the size of the CT increases. There was a problem that.

  Accordingly, the object of the present invention is to eliminate the drawbacks of the prior art, detect the surge current of the main line of the device and detect lightning strikes to the main line (power line), regardless of whether there is an accident in the transmission line, An object of the present invention is to provide a simple surge current detector capable of detecting a lightning strike position generated on a power line.

  Another object of the present invention is to provide a surge current detector capable of realizing downsizing and low consumption of the apparatus.

  To achieve the above object, a simple surge current detector according to the present invention includes a plurality of surge current sensors attached to a plurality of locations of a power line of an overhead power transmission line and receiving a surge current caused by a lightning strike, and the plurality of surge current sensors. Corresponding to the threshold transmission unit provided at the same number of predetermined locations of the overhead power transmission line, and at least when the level information of the surge current exceeds a predetermined value, operates in response to the startup signal. A control unit that manages surge detection information and surge detection time, a wireless transmission unit that operates according to a command from the control unit and transmits information, and a solar cell or primary battery power source for driving each unit. Wirelessly receiving surge current level information, propagation direction information, and time information from the detectors and the plurality of detectors, and using the surge current propagation direction information Identify the two detectors positioned on both sides of the di-generation point, characterized in that it comprises a determining central unit lightning strike position between the surge current level information and the time information of the two detectors.

  As the surge current sensor, a Rogowski coil or a Hall element is preferably used.

  According to the present invention, a solar cell includes a surge current sensor that receives a surge current caused by a lightning strike, and a detector that detects and manages current level information, propagation direction information, and time information. Alternatively, since it can be driven by the primary battery, it can be installed on the power line of the overhead power transmission line, so that it is possible to accurately detect and determine lightning strikes on the power line without being affected by the presence or absence of a power line accident.

Embodiments of the present invention will be described below with reference to the drawings.
The surge current simple detector of the present invention is roughly classified into a surge current sensor, a detector, and a central device. Hereinafter, description will be made separately for each component.

(Surge current sensor)
The surge current sensor is attached to a plurality of locations on the power line of the overhead power transmission line and receives a surge current caused by a lightning strike.
A Rogowski coil is preferably used as the surge current sensor. By using a Rogowski coil, there is no heat generation, saturation, and hysteresis due to magnetic loss compared to the case of using a conventional CT (transformer), and the size and weight can be reduced even when measuring large currents. Can do.
Even if a Hall element is used as the surge current sensor, it is possible to reduce the size and weight in measuring a large current.
Rogowski coils and Hall elements are effective in reducing the power consumption of the detector.

(Detector)
FIG. 1 shows a schematic diagram of the configuration of the detector.
The detector 5 connected to the surge current sensor 4 includes an input circuit 6 that converts a signal from the surge current sensor 4 into a voltage signal, a filter circuit 7 that extracts the surge current from the voltage signal, and a magnitude of the surge current. The comparator 8 for discriminating the surge propagation direction by adding a positive / negative polarity signal to the surge current level using the signal output polarity from the sensor 4, and when the surge current level exceeds a predetermined value A threshold comparator 20 that generates a start signal, a controller 9 that operates in response to a signal from the threshold comparator 20 and manages the surge current level information, propagation direction information, and time information from the comparator 8 in memory. Drives each component of the transmission unit 10 that operates in response to a command from the control unit 9 and transmits memory-managed information to the ground unit, a clock (GPS) 11 that counts a predetermined time, and the detector 5 And it includes a power supply 12 to. The transmission unit 10 is constituted by a mobile phone or a mail transmission device, and the power source 12 is a solar battery or a lithium battery.

(Central device)
The central device is arranged on the ground and receives and aggregates information on the surge current level, surge propagation direction, and reception time detected by the detector 5 by radio, and based on these information, the position of the overhead power transmission line This is to identify whether a lightning strike has occurred.

(Installation example of a simple surge current detector)
An example of installation of the present surge current simple detector on an overhead power transmission line will be described with reference to FIGS.
In FIG. 2, a surge current sensor 4 and a detector 5 are attached to a main line 2 of four conductors of an overhead power transmission line to detect a surge on the main line.
On the other hand, FIG. 3 detects a surge on the GW by attaching the surge current sensor 4 to the overhead transmission line GW (aerial ground wire) 1 and the detector 5 on the top of the steel tower 3.

(Operation of simple surge current detector)
As shown in FIG. 4, a plurality of detectors 15 to 18 of a simple surge current detector are installed at predetermined intervals on the overhead power transmission line 14, and information on the detected surge current level, surge propagation direction, and time is stored in the central device 19. Keep it aggregated. A surge current sensor (not shown) is arranged at a position corresponding to each of the detectors 15 to 18. Hereinafter, the operation of the simple surge current detector will be described with reference to FIGS.

First, a surge current sensor receives a surge current, and the detectors 15 to 18 detect the level of surge current flowing in the overhead power transmission line 14 and the direction of surge propagation.
For example, when a lightning strike or the like occurs between the detector 15 and the detector 16 as shown in FIG. 4, a surge current flows from the surge occurrence point to the left and right. This surge current is detected by the respective surge current sensors provided at the detector 15, the detector 16, the detector 17, and the detector 18.

  The surge currents detected by these surge current sensors are respectively input into detectors 15-18. In the detectors 15 to 18, as shown in FIG. 1, the surge current signal is converted into a voltage signal by the input circuit 6, and then the surge current is extracted from the voltage signal by the filter circuit 7. Is input.

The comparison unit 8 performs step division according to the magnitude (crest value) of the surge current.
For example, as shown in FIG. 5, when the peak value of the surge 13 is between level 5 and level 6, the current level of the surge 13 is determined to be level 5.
Further, the comparison unit 8 determines the polarity, that is, the direction in which the surge current flows, from the surge current signal supplied from the surge current sensor. In the example shown in FIG. 4, in the detector 15, the direction in which the surge current flows is leftward in the figure, and in the detectors 16, 17, and 18, the direction in which the surge current flows is rightward. In the part 8, the polarity − is given, and in the comparison parts in the detectors 16, 17 and 18, the polarity + is given.

The surge current level information in the comparison unit 8, the propagation direction information to which the polarity is given, and the time information from the clock 11 are input to the control unit 9 that manages the memory, and the information managed in the memory is transmitted from the transmission unit 10 to the central unit of the ground unit. 19 (see FIG. 4) is transmitted wirelessly.
The controller 9 outputs an activation signal when the surge current level exceeds a predetermined value set in the threshold comparator 20. The transmission unit 10 operates and transmits in response to a transmission command from the control unit 9.
In normal times, the power consumption can be reduced by keeping the control unit 9 and the transmission unit 10 of the detector 5 in a dormant state.

In the central device 19 shown in FIG. 4, the surge occurrence point is determined based on the surge current level information, propagation direction information and time information received from the detectors 15 to 18.
First, the central device 19 groups the same time information based on the time information.
Based on the surge current propagation direction information received from the grouped information detectors 15 to 18 at the same time, two detectors located on both sides of the surge occurrence point are identified. In FIG. 4, information with a negative polarity is received from the detector 15, and information with a positive polarity is received from the detector 16, so that a lightning strike that has generated a surge current is between the detector 15 and the detector 16. It can be determined that it occurred.
Next, based on the surge current level information received from the detector 15 and the detector 16, at which position between the detector 15 and the detector 16 by proportional calculation according to the attenuation rate at the time of surge propagation of the attached power line. Determine if a lightning strike has occurred.
A method for identifying a lightning strike will be described with reference to FIG. 6. The detection of the detector 15 is detected in three detectors 15 to 17 (of which the detector 15 and the detectors 16 and 17 have different polarities). The attenuation line 22 is drawn with reference to the level A, the attenuation line 23 is drawn with reference to the detection level B of the detector 16 and the detection level C of the detector 17, and the intersection is specified as a lightning strike location.

(Effect of simple surge current detector)
The simple surge current detector of the present embodiment has the following effects.
(1) Wireless transmission for information transmission, and it can be driven by solar cells or primary batteries as a power source, so it can be installed not only on overhead ground wires but also on the main line. Be able to discover.
(2) As the configuration to be attached to the overhead power transmission line, only the surge current sensor that receives the surge current due to lightning strike and the detector that detects and manages the current level information, propagation direction information, and time information are used. The lightning strike on the power line can be accurately detected and determined without being affected by the presence or absence of a power line accident.
(3) By setting the magnitude of the surge current to simple level information with a comparator, it is possible to simplify the apparatus and simplify the amount of transmission information.
(4) Since the time information is intended for grouping of the same surge, extremely high accuracy is not required and the apparatus can be simplified.
(5) The power consumption can be reduced by keeping the control unit and the transmission unit of the detector in a dormant state during normal times.
(6) Since information transmission is wireless and can be driven by a solar cell or a primary battery as a power source, it can be easily applied to a transmission line having no transmission means such as a transmission line power line and an OPGW optical fiber.
(7) Since a Rogowski coil is used as a surge current sensor, there is no heat generation, saturation, or hysteresis due to magnetic loss, and it is possible to reduce the size and weight of large current measurement and contribute to low consumption of the detector. it can.
(8) If a detector is installed on the overhead ground line of the overhead power transmission line as shown in FIG. 2, lightning strikes on the overhead ground line can be easily detected as well.

It is a block diagram which shows the structure of the detector of the simple surge current detector which concerns on this invention. It is the schematic explaining the example of installation of the surge current simple detector which concerns on this invention. It is the schematic explaining the example of installation of the surge current simple detector which concerns on this invention. It is a block diagram of the failure determination system using the simple surge current detector which concerns on this invention. It is a graph which shows an example of a surge current. It is a graph explaining the method for pinpointing a lightning strike point.

Explanation of symbols

1 GW
2 main lines 3 steel tower 4 surge current sensor 5 detector 6 input circuit 7 filter circuit 8 comparison unit 9 control unit 10 transmission unit 11 clock 12 power supply 13 surge 15, 16, 17, 18 detector 19 central device 20 threshold comparison unit 22 23 Attenuation line

Claims (3)

A plurality of surge current sensors that are attached to a plurality of power lines of an overhead power transmission line and receive a surge current caused by a lightning strike,
A threshold comparison unit that is provided in the same number at predetermined locations of the overhead power transmission line corresponding to the plurality of surge current sensors, and that generates a startup signal at least when the level information of the surge current exceeds a predetermined value, and the startup A control unit that operates in response to a signal and manages surge detection information and surge detection time, a wireless transmission unit that operates according to a command from the control unit and transmits information, and a solar cell or a primary battery for driving each unit A power source, and a detector comprising:
Wirelessly receives surge current level information, propagation direction information, and time information from the plurality of detectors, and identifies two detectors located on both sides of the surge occurrence point by the surge current propagation direction information. A central device for determining a lightning strike point between the two detectors from the surge current level information and time information;
A surge current simple detector comprising:   2. The surge current simple detector according to claim 1, wherein a Rogowski coil is used as the surge current sensor.   The simple surge current detector according to claim 1, wherein a hall element is used as the surge current sensor.

Images