JP2010256134A - Equipment for probing accident point - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide equipment for probing an accident point which enables safe and easy probing of the accident point of a distribution line where a ground fault or the like has occurred. <P>SOLUTION: The equipment 1 for probing the accident point includes a plurality of connecting cable parts 21, 22 and 23 of which the tip portions are connected respectively to the individual distribution lines W1, W2 and W3 in a plurality, a DC power supply part 51 which is connected to the respective base end portions of the connecting cable parts 21, 22 and 23 and can impress DC voltage on the connecting cable parts 21, 22 and 23, a switch part 6 which is disposed between the connecting cable parts 21, 22 and 23 and the DC power supply part 51 and can select the connecting cable part whereon the DC voltage is impressed by the DC power supply part 51, and a DC current detecting part 8 which detects a DC current flowing through the distribution line W to which the connecting cable part whereon the DC voltage is impressed is connected. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an accident point search device for searching for an accident point of a distribution line in which an accident such as a ground fault has occurred.

  When a ground fault occurs in a distribution line, it is required to promptly repair the location of the accident (hereinafter referred to as “accident point”) and restore the power supply in the distribution line. For that purpose, it is necessary to quickly identify the accident point and to repair the accident point by blocking the accident occurrence section including the accident point as necessary.

  However, it is difficult to identify the accident point by, for example, measuring the insulation resistance or visually checking the operator. In particular, it is difficult to find a short circuit inside a switch provided on a pillar. Therefore, conventionally, an accident point search device has been used in order to quickly identify an accident point (see, for example, Patent Document 1).

  The fault point survey device is composed of a DC power supply unit for applying a DC voltage to the distribution line in the accident occurrence section, a connection cable unit for connecting the distribution line and the DC power supply unit, and a DC current flowing through the distribution line by applying the DC voltage. A direct current detection unit for detecting current.

  The fault point search device applies a DC voltage to the distribution line in the accident occurrence section, and searches for the presence or absence of a DC current flowing through the distribution line by applying the DC voltage. In other words, a ground fault current (DC current) flows between the application point of the DC voltage by the DC power supply unit in the distribution line and the accident point, but no ground fault current flows at other points on the distribution line. Therefore, the worker specifies the accident point based on whether or not the ground fault current is detected.

JP-A-2-17468

  By the way, for example, when an accident point search device searches for an accident point of a three-phase three-wire distribution line, the search is performed using a connection cable whose tip is divided into three. The tip of this trifurcated connection cable is connected to each of the three distribution lines of the three-phase three-wire distribution line, and the accident investigation device is connected to the three-phase three-wire distribution line 3 via the three-pronged connection cable. A DC voltage is simultaneously applied to the distribution lines.

  Therefore, for example, when one of the three distribution lines has a ground fault, a ground fault current flows only in one distribution line, so that the ground fault current flowing through the distribution line can be easily detected. However, when three of the three distribution lines are grounded, the ground fault current flows through the three distribution lines, so the ground fault current flowing through the three distribution lines becomes too small. This makes it difficult to detect a ground fault current.

  Thereby, when a ground fault has occurred in each of the three distribution lines of the three-phase three-wire distribution line, the tip part connected to the two distribution lines is removed from the three-pronged ends of the connection cable, A DC voltage was applied in this state. That is, for each line, the presence or absence of a ground fault current flowing through the distribution line is detected, and this is performed for each of the three distribution lines.

  In addition, when applying a DC voltage to a distribution line, an operator usually moves to a safe place away from the distribution line and applies the DC voltage because an arc or the like is dangerous. Therefore, in the case as described above, the worker has to climb the power pole every time one of the distribution lines is searched, and to remove and attach the tip of the connection cable. Thus, there has been a problem that exploration of an accident point of a three-phase three-wire distribution line using a conventional accident point exploration device takes a lot of time and effort.

  Further, when the two tip portions of the trifurcated connection cable are removed, the connection portion with the distribution line provided at the tip portion of the connection cable is exposed, and thus a protector for protecting the connection portion is required. Moreover, since the front-end | tip part of the two connection cables removed from the distribution line has the three ends of the connection cable, it will be in the state hung down from one distribution line. For this reason, there is a problem that the load concentrates on one tip portion and the connection with the distribution line becomes unstable.

  An object of the present invention is to provide an accident point search device that can safely and easily specify an accident point of a distribution line in which a ground fault or the like has occurred.

  The present invention is connected to a plurality of connection cable portions each having a distal end portion connected to each of a plurality of distribution lines, and to a base end portion of each of the plurality of connection cable portions, and applies a DC voltage to the plurality of connection cable portions. A possible DC power supply unit, a switch unit arranged between the plurality of connection cable units and the DC power supply unit and capable of selecting a connection cable unit to which a DC voltage is applied by the DC power supply unit, and the DC voltage And a direct current detection unit that detects a direct current flowing through the distribution line to which the connection cable unit to which the connection cable is applied is connected.

  Moreover, it is preferable that the accident point search apparatus of this invention is further equipped with the alerting | reporting part which alert | reports the said connection cable part which applied the said DC voltage among the said some connection cable parts.

  Moreover, it is preferable that the said alerting | reporting part is comprised with a light-emitting body.

  Moreover, it is preferable that the said some connection cable part is equipped with a clamp part in the said front-end | tip part.

  ADVANTAGE OF THE INVENTION According to this invention, the accident point search device which can identify the accident point of the distribution line which a ground fault etc. generate | occur | produced safely and easily can be provided.

It is the schematic which shows schematic structure of the accident point search apparatus which concerns on embodiment of this invention. It is a circuit diagram of the electric power distribution apparatus of the accident point search apparatus which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram illustrating a schematic configuration of an accident point search apparatus 1 according to the present embodiment.
As shown in FIG. 1, an accident point survey apparatus 1 according to the present embodiment includes a three-phase three-wire distribution line W1 having a red-phase distribution line W1, a white-phase distribution line W2, and a black-phase distribution line W3 as a plurality of distribution lines. , W2, and W3, when a ground fault occurs, a DC pulse voltage is selectively applied to the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3 in the accident section separated from the healthy section, and the red phase distribution line W1, The presence / absence of a ground fault current as a direct current flowing through the white phase distribution line W2 and the black phase distribution line W3 is searched. An operator specifies an accident point by the presence or absence of the ground fault current which flows into the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3 searched by the accident point search apparatus 1.

  As shown in FIG. 1, the accident point search device 1 according to the present embodiment includes a plurality of connection cable portions 21, 22, 23 connected to the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3. A plurality of CT sensor units 31, 32, 33 provided in the vicinity of the distal ends of the connection cable units 21, 22, 23, and a plurality of light emitting units 41, 42, 43 provided in the plurality of CT sensor units 31, 32, 33. And a direct current for detecting a direct current flowing through a distribution line to which a connection cable portion to which a direct current pulse voltage is selectively applied is connected among the plurality of connection cable portions 21, 22, and 23. A detection unit 8.

  The plurality of connection cable parts 21, 22, and 23 are connected to the first connection cable part 21 connected to the red phase distribution line W1, the second connection cable part 22 connected to the white phase distribution line W2, and the black phase distribution line W3. The third connection cable portion 23 is configured.

  In addition, since the 1st connection cable part 21, the 2nd connection cable part 22, and the 3rd connection cable part 23 are the same structures, the 2nd connection cable part 22 is demonstrated by demonstrating the structure of the 1st connection cable part 21. FIG. No. 22 is attached to the constituent elements and No. 23 series is attached to the constituent elements of the third connection cable portion 23, and the description of the second connection cable portion 22 and the third connection cable portion 23 is omitted.

  The 1st connection cable part 21 is provided with the cable part 21a and the clamp part 21b provided in the front-end | tip of the cable part 21a. The clamp part 21b is composed of a pair of clamp members that are rotatably connected by a hinge. The clamp part 21b is configured to be able to grip the red phase distribution line W1 by rotating a pair of clamp members so as to sandwich a conductor part (not shown) such as a core wire of the red phase distribution line W1.

The plurality of CT sensor units 31, 32, 33 are a first CT sensor unit 31 provided in the vicinity of the distal end portion of the first connection cable portion 21 and a second CT sensor unit 32 provided in the vicinity of the distal end portion of the second connection cable portion 22. And a third CT sensor portion 33 provided in the vicinity of the distal end portion of the third connection cable portion 23.
The first CT sensor unit 31 detects a direct current flowing through the first connection cable unit 21. Similarly, the second CT sensor unit 32 detects a direct current flowing through the second connection cable unit 22, and the third CT sensor unit 33 detects a direct current flowing through the third connection cable unit 23.

  The plurality of light emitting units 41, 42, and 43 are provided in the first light emitting unit 41 provided in the first CT sensor unit 31, the second light emitting unit 42 provided in the second CT sensor unit 32, and the third CT sensor unit 33. 3 light emitting units 43.

  The first light emitting unit 41 emits light when the first CT sensor unit 31 detects a direct current flowing through the first connection cable unit 21. Similarly, the second light emitting unit 42 emits light when the second CT sensor unit 32 detects a direct current flowing through the second connection cable unit 22, and the third light emitting unit 43 is connected to the third CT sensor unit 33 by the third connection. Light is emitted when a direct current flowing through the cable portion 23 is detected. In addition, LED is used for the light-emitting body in a light emission part.

  The power-applying device 5 is connected to the power supply unit 9 and generates a high-voltage (for example, 5 kV) DC pulse voltage. In addition, the power connection device 5 is connected to the base end portions of the first connection cable portion 21, the second connection cable portion 22, and the third connection cable portion 23, and the first connection cable portion 21, the second connection cable The generated high voltage (for example, 5 kV) DC pulse voltage is applied to the unit 22 and the third connection cable unit 23.

Here, FIG. 2 shows a circuit diagram of the power distribution device 5 of the accident point search device 1 according to the present embodiment.
As shown in FIG. 2, the power applicator 5 includes a casing 50, a DC high voltage generation circuit 51 as a DC power supply unit, a meter display unit 52, a DC / AC converter 59, a switch unit 6, and a notification unit. 7.

  The housing 50 constitutes the external appearance of the power application device 5 and is formed of an insulator. Further, the housing 50 is provided with a ground terminal portion 53 and an input terminal portion 54. An earth cord 53 a is connected to the earth terminal portion 53, and the earth cord 53 a is grounded to the ground G. An external power supply unit 9 is connected to the input terminal unit 54.

The DC high voltage generating circuit 51 has one side connected to the ground terminal portion 53 and the other side connected to a high voltage output terminal portion 55 provided inside the housing 50, and generates a high DC pulse voltage.
Further, a limiting resistor 56 is connected in series with the DC high voltage generating circuit 51 between the ground terminal portion 53 and the high voltage output terminal portion 55.

  The meter display unit 52 is connected in parallel with the DC high voltage generation circuit 51 between the ground terminal unit 53 and the high voltage output terminal unit 55. The meter display unit 52 displays the output amount of the high voltage DC pulse voltage generated by the DC high voltage generation circuit 51.

Further, a discharge resistor 58 is connected between the ground terminal portion 53 and the high-voltage output terminal portion 55 through a switch 57 in parallel with the DC high-voltage generation circuit 51. The discharge resistor 58 constitutes a safety device of the power application device 5.
For example, if the ground capacitance between the three-phase three-wire distribution lines W1, W2, W3 and the ground G is large, the three-phase three-wire distribution line W1 even if the output of the power application device 5 is reduced after work. , W2 and W3 are charged with a high voltage for a long time, and if an operator accidentally touches the three-phase three-wire distribution lines W1, W2 and W3, an electric shock may occur. For this reason, when the power supply device 5 is turned off, the switch 57 is automatically turned on, and the high-voltage output terminal portion 55 and the ground terminal portion 53 are grounded via the discharge resistor 58. The electric charge stored in the ground capacitance of the electric wires W1, W2, W3 is discharged, and the charging voltage of the three-phase three-wire distribution wires W1, W2, W3 can be forcibly lowered.

  The DC / AC converter 59 is connected between the DC high voltage generation circuit 51 and the input terminal portion 54. The DC / AC converter 59 boosts the DC 12V of the in-vehicle battery, for example, when an in-vehicle battery as a power source is used.

The switch unit 6 includes a first switch unit 61 connected between the high-voltage output terminal unit 55 and the red-phase distribution line W1, and a second switch unit connected between the high-voltage output terminal unit 55 and the white-phase distribution line W2. 62 and a third switch portion 63 connected between the high-voltage output terminal portion 55 and the black phase distribution line W3.
The first switch unit 61 applies a DC pulse voltage to the red-phase distribution line W1 by pressing (selection) by the operator. That is, when the first switch unit 61 is pressed, a DC pulse voltage is applied to the red phase distribution line W1. Similarly, the second switch unit 62 applies a DC pulse voltage to the white phase distribution line W2 when pressed by the operator, and the third switch unit 63 applies a DC pulse voltage to the black phase distribution line W3 when pressed by the operator. . That is, when the second switch unit 62 is pressed, a DC pulse voltage is applied to the white phase distribution line W2, and when the third switch unit 63 is pressed, a DC pulse voltage is applied to the black phase distribution line W3.

  The notification unit 7 includes a first notification unit 71 connected between the first switch unit 61 and the red phase distribution line W1, and a second notification unit connected between the second switch unit 62 and the white phase distribution line W2. 72, and the 3rd notification part 73 connected between the 3rd switch part 63 and the black phase distribution line W3.

The 1st alerting | reporting part 71 is comprised by LED as a light-emitting body. The 1st alerting | reporting part 71 is comprised so that a predetermined | prescribed electric current may flow by the press of the 1st switch part 61, and, thereby, LED may light-emit.
Similarly, the second notification unit 72 and the third notification unit 73 are configured by a light emitter, and the second notification unit 72 emits light due to a current that flows when the second switch unit 62 is pressed, and the third notification unit 73. The light is emitted by the current that flows when the third switch 63 is pressed.

As shown in FIG. 1, the DC current detection unit 8 includes an insulating operation rod 80 formed in a rod shape, and a detection unit 81 connected to the tip of the insulation operation rod 80.
The insulating operation rod 80 is formed of an insulator such as fiber reinforced plastic. For example, an operator who has boarded an aerial work vehicle grips the base end portion of the insulating operation rod 80 and detects the distal end detection portion 81. Is used to lock the red phase distribution line W1, the white phase distribution line W2 and the black phase distribution line W3 at high places.

  The insulating operation rod 80 may be a joint type in which a plurality of insulating cylinders having different diameters are connected so as to be expandable and contractable in the axial direction. It is possible to position the detection unit 81 to a position far from the three-phase three-wire distribution line with a small movement amount in a work vehicle or the like.

The detection unit 81 includes a main body unit 82, a locking unit 83 that locks the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3, a red phase distribution line W1 that locks the locking unit 83, and white A current detector (not shown) for detecting a direct current flowing through the phase distribution line W2 or the black phase distribution line W3.
The main body portion 82 is formed in a substantially rectangular parallelepiped shape, and the distal end portion of the insulating operation rod 80 is connected to the lower portion of the main body portion 82. The main body 82 has a drip-proof structure because the detection unit 81 is used outdoors.

The locking portion 83 is formed at a position (in the vicinity) adjacent to the connecting portion of the insulating operation rod 80 in the lower portion of the main body portion 82. The locking portion 83 is formed so as to be cut out in a state of penetrating in the thickness direction upward of the main body portion 82.
The locking part 83 is for inserting the distribution line from the lower side of the main body part 82 and for locking the main body part 82 to the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3 so as to be hooked on the distribution line. Provided.
The current detection unit is built in the main body unit 82 and detects a ground fault current flowing through the red phase distribution line W1, the white phase distribution line W2, and the black phase distribution line W3.

  The detection unit 81 includes a level detection circuit that determines the output of the ground fault current detected by the current detector, and a plurality of lights that emit light of a predetermined color according to the output level of the ground fault current determined by the level detection circuit. It is good also as a structure which provides this light-emitting body. By configuring the light emitter to emit a predetermined color according to the output level of the ground fault current of the level detection circuit, in addition to the presence or absence of the ground fault current, for example, the output level of the ground fault current can be easily visually determined from below. It becomes possible to confirm.

Next, the usage method of the accident point search apparatus 1 which concerns on this embodiment is demonstrated.
First, the worker grounds the ground cord 53 a provided in the power-applying device 5 to the ground G.
Next, the worker connects the first connection cable portion 21 to the red phase distribution line W1. Specifically, the operator holds the clamp part 21b provided at the tip of the first connection cable part 21 by the connecting conductor part (not shown) provided in the red-phase distribution line W1, 1 The connection cable part 21 is connected to the red phase distribution line W1.

  When the first connection cable part 21 is connected to the red phase distribution line W1, the operator then connects the second connection cable part 22 to the white phase distribution line W2, and similarly the third connection cable part 23 to the black phase distribution line W3. Connect.

  When the first connection cable part 21 is connected to the red phase distribution line W1, the second connection cable part 22 is connected to the white phase distribution line W2, and the third connection cable part 23 is connected to the black phase distribution line W3, the operator Next, the power application device 5 is connected to the power supply unit 9. For example, when using a vehicle-mounted battery as the power supply unit 9, it is connected to the vehicle-mounted battery.

When the power application device 5 is connected to the power supply unit 9, the operator hooks the DC current detection unit 8 at an arbitrary position of the red phase distribution line W <b> 1 and hooks the red phase distribution line W <b> 1 on the locking part 83 of the DC current detection unit 8. To lock.
When the DC current detection unit 8 is locked at an arbitrary position of the red phase distribution line W <b> 1, the operator presses the first switch unit 61 and applies a DC pulse voltage to the first connection cable unit 21.

  When the operator presses the first switch unit 61, the first notification unit 71 provided in the power application device 5 emits light to notify that the DC pulse voltage has been applied to the first connection cable unit 21. Similarly, the output amount of the DC pulse voltage output to the meter display unit 52 is displayed.

  Here, in the accident section cut off from the healthy section, when a ground fault has occurred at the point A of the red-phase distribution line W1 shown in FIG. 1, the ground G passes through the point A from the connection point of the clamp portion 21b. A ground fault current flows in When a ground fault current flows through the first connection cable unit 21, the first CT sensor unit 31 detects that a current has flowed through the first connection cable unit 21, and a first light emitting unit provided in the first CT sensor unit 31. 41 emits light. This makes it easy to recognize that a direct current is flowing through the first connection cable portion 21.

  In addition, a ground fault current corresponding to the DC pulse voltage flows between the connection point of the clamp part 21b and the point A, but the ground fault current does not flow in other sections. Therefore, for example, when the DC current detection unit 8 is locked at a position indicated by a solid line in FIG. 1, a ground fault current (DC current) is detected by the DC current detection unit 8. On the other hand, if the DC current detection unit 8 is locked at the position shown by the wavy line in FIG. 1, the ground current (DC current) is not detected by the DC current detection unit 8.

  In this way, the direct current detection unit 8 is positioned at an arbitrary position in the red phase distribution line W1, and the direct current pulse voltage is applied to the red phase distribution line W1 through the first connection cable unit 21 by the power application device 5. By this, it becomes possible to specify the accident point in the red phase distribution line W1.

  By performing the same operation as described above for the white phase distribution line W2 and the black phase distribution line W3, it is possible to specify the point of failure in the white phase distribution line W2 and the black phase distribution line W3.

According to the accident point search device 1 according to the present embodiment having the above-described configuration, the following effects can be obtained.
The accident point search device 1 according to the present embodiment is selected as the first connection cable portion 21, the second connection cable portion 22, and the third connection cable portion 23 connected to the three-phase three-wire distribution lines W1, W2, W3. The first switch unit 61, the second switch unit 62, and the third switch unit 63 for applying a direct current pulse voltage are provided. Therefore, the DC pulse voltage is applied by selecting the three-phase three-wire distribution lines W1, W2, and W3 to which the first connection cable portion 21, the second connection cable portion 22, and the third connection cable portion 23 are connected one by one. It becomes possible to make it. Thereby, even when all of the three-phase three-wire distribution lines W1, W2, and W3 are grounded, for example, the shunt current of the ground-fault current that flows through each of the three-phase three-wire distribution lines W1, W2, and W3 This makes it possible to prevent the ground fault current from becoming excessively small and thereby making it difficult to detect the ground fault current.

  In addition, for example, in a state where the first connection cable portion 21, the second connection cable portion 22, and the third connection cable portion 23 are connected to the three-phase three-wire distribution lines W1, W2, and W3, respectively, the first switch portion 61, Since the DC pulse voltage is applied by the second switch unit 62 and the third switch unit 63, each time one of the three-phase three-wire distribution lines W1, W2, W3 is searched as in the prior art, it climbs to the utility pole, There is no need to remove and attach the tip of the connection cable portion 2. This makes it possible to easily search for the distribution line in a short time.

  In addition, the first connection cable part 21, the second connection cable part 22, and the third connection cable part 23 are explored in a state where they are connected to the three-phase three-wire distribution lines W1, W2, and W3, respectively. There is no need for a protector or the like for protecting the clamp portions 21b of the connection cable portions 21, 22, and 23. In addition, since the search is performed in the connected state, the load is concentrated on the distribution line to be searched among the three-phase three-wire distribution lines W1, W2, and W3, and the connection with the distribution line may become unstable. Absent.

  In addition, for example, even in the case of a one-phase ground fault, it is possible to quickly limit phases by applying one line at a time using the switch unit.

  Moreover, what is called a cable clamp which has a clamp part in a front-end | tip part is used for the accident point investigation apparatus 1 which concerns on this embodiment as a connection cable part. Therefore, for example, it becomes possible to attach the cable clamp to the distribution line by operating the insulating jacket. Thereby, the attachment work of a connection cable part becomes a safe and simple thing.

In addition, this invention is not limited to the said embodiment at all, and the technical scope of this invention is not limited to these.
For example, in the present embodiment, the three-phase three-wire distribution line composed of the red-phase distribution line W1, the white-phase distribution line W2, and the black-phase distribution line has been described as the plurality of distribution lines, but the present invention is not limited to this. . A plurality of distribution lines can be effectively used for two or more distribution lines.

DESCRIPTION OF SYMBOLS 1 Accident point search device 5 Power supply device 6 Switch part 7 Notification part 8 DC current detection part 9 Power supply part 21 1st connection cable part 21b 1st clamp part 22 2nd connection cable part 22b 2nd clamp part 23 3rd connection cable Part 23b Third clamp part 51 DC high voltage generation circuit (DC power supply part)
W1 Red phase distribution line W2 White phase distribution line W3 Black phase distribution line

Claims (4)

A plurality of connecting cable parts each having a tip connected to each of the plurality of distribution lines;
A direct current power supply unit connected to a base end portion of each of the plurality of connection cable portions, and capable of applying a direct current voltage to the plurality of connection cable portions;
A switch unit that is arranged between a plurality of the connection cable units and the DC power supply unit, and is capable of selecting a connection cable unit to which a DC voltage is applied by the DC power supply unit;
A direct current detection unit for detecting a direct current flowing in the distribution line to which the connection cable unit to which the direct current voltage is applied is connected;
An accident point search device characterized by comprising:   The accident point search device according to claim 1, further comprising a notification unit that notifies the connection cable unit to which the DC voltage is applied among the plurality of connection cable units.   The accident point search device according to claim 2, wherein the notification unit includes a light emitter.   The accident point search device according to claim 1, wherein the plurality of connection cable portions include a clamp portion at the tip portion.

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