JP2984104B2 - Distribution line monitoring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution line monitoring device.

[0002]

2. Description of the Related Art In a modern society, instantaneous power outages are not allowed, and it is necessary to always grasp the state of power transmission or power distribution and to predict the occurrence of an accident or prevent the accident from occurring.

In response to such a demand, a conventional distribution line monitoring device used for an overhead distribution line has a zero-phase current transformer (hereinafter referred to as Z) built in a relay switch installed on a utility pole.
CT) or zero-phase transformer (hereinafter called ZPD)
The power distribution status was measured and monitored electrically.

[0006] FIG. 6 shows a state of installation of a relay switch 5 on a utility pole 1. A three-phase distribution line 2 is installed on a utility pole 1.
The distribution line 2 is fixed to the arm 4 on the power pole 1 by a tension insulator 3 provided for each fixed section on the power pole 1 and is stretched.

In FIG. 6, the distribution line 2 is kept slack, and devices such as a relay switch 5 are installed between subsequent connections. The three-phase distribution line 2 on the arrow 6 side is connected to the three-phase distribution line 2 on the arrow 7 side via the insulator 3 via the relay switch 5. The above-described ZCT or ZPD and a distribution line cutoff switch (both not shown) are built in the relay switch 5 shown in FIG. 6, and the ZCT or ZPD detects an abnormality in the distribution line. , To interrupt the communication or switch to the substation. Such an abnormality is configured to be transmitted to a substation or the like via a communication line 8 installed in the middle of the utility pole 1.

[0006]

As shown in FIG. 6,
The three distribution lines 2 are guided to the inside of the relay switch 5 and further Z
Focus on CT and other parts. Even in the case of ZPD, it is connected via a capacitor or the like. For this reason, the inter-phase voltage of the distribution line 2 is concentrated in a very narrow place, the insulation cannot be maintained depending on the deterioration due to long-time use or the airtight state of the relay switch 5, and the short circuit between the lines or the distribution line In some cases, the cause of the accident was caused by the short circuit of the equipment and the cause of the accident.

The distribution line monitoring device constantly monitors the current and voltage flowing through the distribution line to detect or predict an accident. This information can be stored over long periods of time,
In addition, there must be no error under any weather conditions such as rain and snow, and it must be stable.

[0008] The present invention takes into account the problems of such a conventional distribution line monitoring device, and can be installed for a long period of time.
It is another object of the present invention to provide a distribution line monitoring device capable of performing stable monitoring without causing an error under all weather conditions such as rain and snow.

[0009]

According to the present invention, there is provided an upper and lower case body for sandwiching and fixing a distribution line, and a stray capacitance between the distribution line and the ground which is built in the upper or lower case body by two conductors. A capacitor divider for dividing the voltage;
Built in the same case as the voltage divider
A first conductor connected to one conductor of the compressor;
A distribution line monitoring device comprising an optical voltage sensor housed between a capacitor divider and the first conductor and connected to two conductors of a capacitor divider.

Further, according to the present invention, the dimension of a case body in which a capacitor voltage divider and an optical system voltage sensor are accommodated in a direction parallel to a distribution line is smaller than a length of the capacitor voltage divider in a direction parallel to the distribution line. It is a distribution line monitoring device that is twice or more.

[0011] The present invention also relates to the above-mentioned distribution line of the capacitor voltage divider, wherein the width direction perpendicular to the distribution line of the outer shape of the case body accommodating the capacitor voltage divider and the optical voltage sensor is provided.
The distribution line monitoring device is characterized in that the width is at least twice the width in a direction perpendicular to the distribution line.

[0012] The present invention also relates to a distribution line monitoring method, wherein the cross-sectional shape of the case body accommodating the capacitor voltage divider and the optical type voltage sensor in the direction perpendicular to the distribution line has a trapezoidal shape having a shorter bottom side. Device.

Further, according to the present invention, the cross-sectional shape of the case housing the capacitor voltage divider and the optical voltage sensor in a direction perpendicular to the distribution line is substantially arc-shaped or semi-circular with respect to the center of the distribution line. It is a distribution line monitoring device in a state.

[0014]

According to the present invention, stable monitoring can be performed without errors even if the apparatus is installed for a long time or under all weather conditions such as rain and snow.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

First, the outline of the optical voltage sensor will be briefly described. The optical voltage sensor utilizes the Pockels effect and senses the amount of change in the birefringence of the crystal relative to the electric field when light passes through the Pockels element, and detects the electric field.

In the present invention, the current sensor is housed in the case at the same time as the voltage sensor. Therefore, the outline of the optical current sensor will be described. The optical type current sensor utilizes the Faraday effect, and detects a magnetic field generated in the vicinity when a current flows through an electric wire by the rotation angle of light passing through the Faraday element. FIG. 3 is a schematic diagram in which such a voltage sensor and a current sensor are integrated and installed on the distribution line 2.

A horseshoe-shaped core 32 having a gap 31 for a current sensor is installed on the distribution line 2, and an optical current sensor 108 is arranged in the gap 31. The optical voltage sensor 109 is provided with a capacitor voltage divider 110 for dividing the stray capacitance on the distribution line 2,
The two conductors are connected to the optical voltage sensor 109. Optical fibers for input and output are connected to these optical type voltage / current sensors, and one optical fiber cable 1 is connected midway.
13 and is led to the connector 37 at the end.

FIG. 4 shows an equivalent circuit between the distribution line 2, the voltage sensor 109 and the ground 42. A capacitor voltage divider 110 and a voltage sensor 109 are provided between the distribution line 2 and the ground 42. C ₁ 43 is the capacitance between the conductor of the distribution line 2 and the inner electrode of the capacitor voltage divider 110, and C ₂ 44 is the capacitance of the inner and outer electrodes of the capacitor voltage divider 110. C ₃ 45 is a capacitance between terminals of the voltage sensor connected in parallel to the inner and outer electrodes of the capacitor divider 110. C ₄ 46 is the capacitance including the atmosphere formed between the outer electrode of the capacitor voltage divider 110 and the ground 42.

These C ₁ 43, C ₂ 44, C ₃ 45, C ₄
Of the 46, C ₁ 43, C ₂ 44, and C ₃ 45 are determined by the composition of the component parts, but only C ₄ 46 has the degree of humidity in the atmosphere, the location of the earth portion which becomes the ground 42, The voltage output of the capacitor voltage divider 110 fluctuates due to the influence of whether or not a water film or snow can be formed between the outer electrode of the capacitor voltage divider 110 and the ground. Therefore, it is intended to obtain a divided voltage output by the capacitor voltage divider 110 which does not receive the fluctuation of the C ₄ 46.

That is, FIG. 5 shows a place which is considered to be changed by an external influence from the equivalent circuit. If the side or the outer periphery of the distribution line monitoring device is wet, the ground 1
The position of the outer electrode of the capacitor voltage divider 110 with respect to the position 2 and the high potential portion are confused and fluctuate. At this time, the capacitance between the grounds is C ₄ '52
The variable capacity is as follows. The present invention takes measures against the parts affected by water, including rain and snow.

Hereinafter, specific embodiments of the present invention will be shown and described in detail.

FIG. 1 is an exploded perspective view of a distribution line monitoring device according to the present invention. Lower case body 101 for distribution line 2
And the upper case body 102 is sandwiched from above and below, and as shown by the arrow 10, the upper case body 102 is turned over and fixed. Recesses 103 and 104 are formed in the lower case body 101 and the upper case body 102, respectively, and the distribution line 2 is fitted and fitted. The upper case body 102 has a depth that covers substantially the entire side surface of the lower case body 101. The lower case body 10
A hole 105 for inserting a core with a gap (not shown) installed in the upper case body 102 is formed in the upper surface portion where the one distribution line installation concave portion 103 is formed. Lower case body 1
01 has a box shape on the opposite side of the distribution line installation concave portion 103, and has an optical current sensor 108 and a voltage sensor 10 inside.
9. The capacitor voltage divider 110 for the voltage sensor is installed. The voltage sensor 109 and the electrode terminal 111 of the capacitor voltage divider 110 are connected. Input and output of light from the current sensor 108 and the voltage sensor 109 are performed by an optical fiber 112 and connected to an optical fiber cable 113 introduced from the outside in the lower case body 101. Current sensor 108, voltage sensor 109, capacitor voltage divider 1 in lower case body 101
After storing 10, the package is sealed with the back cover 114. Back cover 11
4, a conductor 116 is provided on the inner flat portion 115,
This conductor 116 is connected to one electrode terminal of the capacitor voltage divider 110 by a metal wire 117.

Although the upper surface of the upper case body 102 is not shown in FIG. 1, the distribution line installation concave portion 104 and the outside of the upper surface portion are separated from each other by about 30 mm, which is equivalent to the installation height of the gap. By separating the distribution line and the upper surface outside in this way, even if there is water leakage due to snow or rain on the outside, the effect can be reduced.

FIG. 2 is a sectional view of a distribution line monitoring device according to the present invention. A capacitor voltage divider 110 is mainly displayed inside the lower case body 101, and the capacitor voltage divider 110
Is composed of a dielectric substance 203 sandwiched between an inner electrode 201 and an outer electrode 202.

The condenser voltage divider 110 and the back cover 114
The space between them is embedded with the resin 204. Back cover 11
4, a conductor 116 is provided inside the capacitor voltage divider 1
It is connected to the ten outer electrodes 202 by metal wires 117. In this configuration, the optical voltage sensor 109 is provided between the outer electrode 202 of the capacitor voltage divider 110 and the conductor 116 provided inside the back cover 114. The connection between the terminal of the voltage sensor 109 and the capacitor voltage divider 110
As shown in the figure, one is connected to the inner electrode 201 of the capacitor voltage divider 110, the other is connected to the outer electrode 202, and the outer electrode 202 is connected to the conductor 116 of the back cover 114.

The outside of the back cover 114 has an uneven shape 118,
The structure has a longer horizontal surface distance and is less wettable.
The upper case body 102 overlaps and is fixed to the lower case body 101, but also has a box shape, and the overlapping portion 205 with the lower case body 101 is almost equal in height to the lower case body 101. The lower case body 101 becomes narrower toward the bottom and has a trapezoidal cross-sectional shape with a shorter bottom side. The reason for the effectiveness of this shape is that since the dielectric constant is different at the boundary between the sensor case and the outside air, the potential from the distribution line 2 is bent inward, and the influence of rain flowing along the side surface of the upper case body 102 due to the inward bending. This is because they will not be affected. By doing so, it is possible to prevent water from rising between the upper and lower cases by capillary action. Further, the upper case body 102 has an inclined upper surface portion 206, so that rainwater and snow are less likely to collect. In addition,
The cross-sectional shape of the upper surface of the
Changes the inclination angle of the upper part of the upper case like an ellipse
Make it harder for rainwater and snow to collect
be able to. The distance between the upper surface portion 206 and the distribution line 2 is set to be at least a certain value, and in the present invention, the distance is set to be at least 30 mm. The greater the distance, the smaller the effect of snow and the like.

Although not shown in FIGS. 1 and 2, the size of the condenser voltage divider 110 and the outer case body, especially the upper case body 202 which is in direct contact with rain and snow, should be at least twice as large as the condenser voltage divider 110 in the horizontal direction. Can reduce the influence.
Alternatively, the width direction of the lower case body 101 is configured to be at least twice the width of the capacitor voltage divider 110.

In the longitudinal direction, the length is set to be at least twice as large as that of the capacitor voltage divider, preferably three times. The reason for this is also to keep the leakage part due to rain etc. away from the high potential position of the distribution line.

Although the present invention has been described with reference to the drawings in which all the configurations shown in the embodiments are employed, it is effective to use each invention alone or in combination. In the present embodiment, the description has been made of a single distribution line. However, the same configuration and effect can be obtained even when each of the three-phase distribution lines is installed.

[0031]

As is apparent from the above description, in the distribution line monitoring apparatus according to the present invention,
It is possible to provide a stable device which can reduce a change in characteristics due to a climatic change, in particular, wetness due to rainwater and a change in characteristics due to snow. Further, according to this configuration, it becomes possible without increasing the size of the device.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a distribution line monitoring device according to an embodiment of the present invention.

FIG. 2 is a partial sectional view of the same device.

FIG. 3 is a conceptual diagram of the device using an optical voltage sensor and a current sensor.

FIG. 4 is an equivalent circuit diagram of a distribution line, a capacitor voltage divider, and the ground on the voltage sensor side of the device.

FIG. 5 is an equivalent circuit diagram when there is an external influence between a distribution line, a capacitor voltage divider, and the ground.

FIG. 6 is an installation diagram on a utility pole of a relay switch incorporating a conventional zero-phase current transformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power pole 2 Distribution line 5 Relay switch 8 Communication line 101 Lower case body 102 Upper case body 108 Current sensor 109 Voltage sensor 110 Capacitor voltage divider 113 Optical fiber 114 Back cover 116 Conductor 117 Metal wire 118 Unevenness 201 Inner electrode 202 Outside Electrode 203 dielectric substance 204 resin

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kazuo Toda 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Tohru Matsuda 3-2-2 Nakanoshima, Kita-ku, Osaka-shi, Kansai, Kansai Inside Electric Power Company (72) Inventor Shoichiro Nishimura 3-2-2, Nakanoshima, Kita-ku, Osaka-shi, Osaka Prefecture Inside Kansai Electric Power Company (72) Inventor Hiroyuki Fudo 3-2-2, Nakanoshima, Kita-ku, Osaka, Kansai (56) References JP-A-1-270679 (JP, A) JP-A-3-255963 (JP, A) JP-A-5-34377 (JP, A) JP-A-61-176457 (JP) , U) (58) Field surveyed (Int.Cl. ⁶ , DB name) G01R 15/06 G01R 15/24

Claims (5)

(57) [Claims] An upper and lower case body for sandwiching and fixing a distribution line, a capacitor voltage divider built in the upper or lower case body, and dividing a stray capacitance between the distribution line and the ground by two conductors. Same case as the capacitor voltage divider
And is connected to one conductor of the capacitor voltage divider.
Connected first conductor, the capacitor voltage divider and the second
A distribution line monitoring device comprising: an optical voltage sensor housed between one conductor and connected to two conductors of the capacitor voltage divider. 2. A dimension of a contour of the case body accommodating the capacitor voltage divider and the optical voltage sensor in a direction parallel to the distribution line is a length of the capacitor voltage divider in a direction parallel to the distribution line. The distribution line monitoring device according to claim 1, wherein the distribution line monitoring device is at least twice as large. 3. The power distribution of the capacitor voltage divider, wherein the width direction of the outer shape of the case body in which the capacitor voltage divider and the optical voltage sensor are housed is perpendicular to the distribution line.
2. The distribution line monitoring device according to claim 1, wherein the width is at least twice the width in a direction perpendicular to the line. 4. A cross-sectional shape of the case body accommodating the capacitor voltage divider and the optical voltage sensor in a direction perpendicular to the distribution line is a trapezoidal shape having a shorter bottom side. The distribution line monitoring device according to claim 1. 5. A sectional shape of the case body accommodating the capacitor voltage divider and the optical voltage sensor, which is substantially arc-shaped or semi-circular in a direction perpendicular to the distribution line, centering on the distribution line center. The distribution line monitoring device according to claim 1, wherein the distribution line monitoring device has a semi-elliptical shape.