JPH01270678A - Monitoring apparatus of power distribution line - Google Patents

Abstract

PURPOSE:To install an apparatus and to enable the monitoring of each three-phase electric line in the state wherein the electric lines are installed at a prescribed interval between them, by forming a recessed part for installing the electric lines in a sensor accommodating frame body. CONSTITUTION:An apparatus comprises an optical type current sensor 12, an optical type voltage sensor 13, a sensor accommodating frame body 14, a core 15 for converging a magnetic field, a screw body for fixing the core, a T-shaped pin body 17 for fixing the frame body 14 to an electric line 11, and a protective cover body. As for the gist of installation, the frame body 14 wherein the optical type current sensor 12 or the optical type voltage sensor 13 is accommodated is held by hand and put in the electric line 11, the T-shaped member 17 for fixation, for instance, is inserted between the frame body 14 and the electric line 11, and the hand is detached from the frame body 4. Then the optical sensor 12 and 13 are fixed on the electric line 11. On the occasion, the positional relationship between the electric line 11 and the optical sensors 12, 13 can be fixed without an error. Then, by fitting the core 15 to the frame body 14, the concentration of a magnetic field on the optical sensors 12, 13 is facilitated, and by projecting a light to a sensor element after installation, the state of operation of the electric line 11 can be monitored.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a power distribution line monitoring device.
-7 The device is installed to monitor the operating status of relatively high voltage distribution lines or transmission lines.

In modern society, we are in a situation where instantaneous power outages are not tolerated, and it is necessary to constantly grasp the status of power transmission or distribution and to predict or prevent accidents from occurring.Distribution line monitoring device of the present invention In order to prevent such accidents, a current/voltage sensor is installed on each three-phase line to monitor the balance of the three phases.

Conventional technology Conventionally, distribution line monitoring devices used for overhead distribution lines have been installed on utility poles and built into relay switches. Three-phase electric wires were inserted into the hole and the signal output from the ZCT was detected when there was an imbalance in the voltage and current of each phase. However, in this method, the electrical lines to which high voltage is applied are grouped together in the ZCT section within the relay switch, making insulation extremely difficult. Also always Z
High voltages are in close proximity within the CT, and long-term reliability cannot be guaranteed. In the past, many accidents occurred in this area, and to prevent them, it was necessary to periodically replace the electrical lines in the relay switch. Figure 5 shows how relay switches are installed on utility poles.

A three-phase electric line 2 is installed on a utility pole 1. The electric line 2 is fixed and tensioned to a brace 4 on the electric pole 1 by means of tension insulators 3 provided at certain intervals on the electric pole 1''. In Figure 6, the electric line 2 is cut and pulled using a winch (not shown) to create a distribution line with no slack, and a device such as a relay switch 5 is installed between the connections. . In Fig. 6, a relay switch 5 is installed between the electric lines, and an arrow 6
The three-phase electric line 2 is connected to the three-phase electric line 2 indicated by the arrow 7 via the insulator 3 and the relay switch 5. The relay switch 5 shown in FIG. 5 has the above-mentioned ZCT and electric line cutoff switch (both not shown) built in, and when the ZCT detects an abnormality in the electric line, the switch is activated. It is something to cut.

Problems to be Solved by the Invention As shown in FIG. 5, three electric lines 2 are connected to a relay switch 5.
Concentrate on the section. Inside the K-type switch 5, the three electric lines become even closer and gather inside the ZCT. As a result, the phase voltage of the three wires is applied to a very narrow area, and depending on deterioration due to long-term use or the airtightness of the relay switch 5, insulation may not be maintained. This could lead to a short circuit between the line or between the line and the ZCT, resulting in a power outage. In order to solve this problem, the present invention attempts to obtain information on each power line by installing a monitoring device in a state where three-phase power lines and gland lines are installed at regular intervals. Furthermore, the information obtained is that the current and voltage flowing through the electric line can be constantly monitored at the same time without having to operate the electric line, and even after long-term installation, there will be no errors, and there are three electric lines. It must be something that has little variation in installation.

Means for Solving the Problems The present invention provides four parts for installing electric wires in a sensor storage frame that houses an optical current or voltage sensor, and inserts electric wires into these four parts. Furthermore, a fixing member is inserted into the recess to fix the electric line to the storage frame.

Alternatively, a configuration may be used in which a magnetic field convergence core is attached to a part of the storage frame and a capacitor voltage divider is installed inside the storage frame, and the magnetic field convergence core is installed so that the electric line is located in the center. However, a configuration in which the optical current sensor is located in the air gap portion of the core is also possible.

Operation The above configuration makes it extremely easy to install the distribution line monitoring device on the power line. To install the sensor storage frame, hold the frame housing the optical current or voltage sensor in your hand and fit it into the power line, for example, insert a T-shaped fixing member between the sensor storage frame and the power line. When you release your hand, the monitoring sensor will be fixed on the wire. At this time, the positional relationship between the electric line and the optical sensor can be kept constant without any error. By attaching the core to the frame, it becomes possible to easily concentrate the magnetic field on the sensor. Furthermore, since the operating status of the power distribution line (electrical line) can be monitored by shining light into the sensor unit immediately after installation, it has a large impact on the surrounding area and can make a major contribution to the power-related industry. By detecting current or voltage using this optical method, the present invention enables a highly reliable detection system, which can reduce the causes of conventional accidents.Furthermore, by transmitting signals using optical fiber cables, it is possible to detect abnormalities or control them from a remote location. It becomes possible. The present invention monitors the operating status of power distribution lines, and is not limited to three-phase power lines; similar monitoring is also possible by monitoring negative-phase or two-phase lines.

EXAMPLE The principle of an example of the optical current sensor and voltage sensor used in the present invention will be briefly described. First, an optical current sensor utilizes the Faraday effect, and uses a magneto-optical element to detect the magnetic field generated in the vicinity when current flows through an electric line.

Refer to Figure 3 for a detailed explanation of the optical current sensor.
When you do this, random light 102 from a light source 101 such as an LED
The light is passed through a polarizing plate 103 to form linearly polarized light 104 and is made incident on a magneto-optic crystal 105 having a length of crystal.

When a magnetic field H106 is applied in the same direction as the traveling direction of this light, the polarization plane of the emitted light 107 is rotated by an angle θ108.

The magnitude of the rotation angle of θ108 can be extracted as light intensity using an analyzer 109 installed on the output side.

The transmitted polarization direction of the polarizer 103 and analyzer 109 is set to 45°.
When shifted, the light output intensity is expressed by the following equation.

pasin(2θ) ~ 2θ=2VLH (θ<<1) V: Verdet constant, L: material length, when θ(1), the optical output P is proportional to the magnetic field H106. With this configuration, the optical output P is proportional to the magnetic field H106. ), the magnitude of the flowing current can be measured by measuring the magnetic field 106 generated around the conductor.

Next, the optical voltage sensor utilizes the Pockels effect, and detects the electric field by sensing the amount that the crystal multilayer changes in response to the electric field when light passes through the Pockels element. Specifically, the optical voltage sensor will be explained with reference to FIG. 4. Random light 30 from a light source (not shown)
1 is passed through a polarizing plate 302 to become linearly polarized light 303, and then passed through a wavelength plate 304 of % of the light source wavelength to become circularly polarized light 305. Circularly polarized light 305 is passed through a Pockels element 306 and an analyzer 307
Receive it at At this time, a voltage 308 is applied to the conductor (for example, between an electric line and the ground) to the Pockels element 306, and depending on the directionality and the strength of the voltage application, the circularly polarized light 305 becomes vertically elongated elliptically polarized light 309, or the circularly polarized light 305 becomes horizontally elongated elliptically polarized light 310. It becomes.

This change is received by an analyzer 307, and the change in light amount is converted into a voltage change.

Next, FIG. 1 is a cross section of a device according to an embodiment of the present invention attached to an electric line, showing a sensor section and a core section.

The capacitor voltage dividing section is shown. The configuration of the monitoring section of the present invention includes an optical current sensor 12 having a lap integration core (magnetic core) 15 for concentrating the magnetic field generated around the electric line 11, and a link between the electric lines 11 and 9. .

Voltage divider 201 that divides the voltage between the ground and the capacitor
Optical voltage sensor 13 to which a divided voltage of
It becomes more. A sensor storage frame 14 in which these are integrated is installed and fixed on the electric line 11.

The voltage divider 201 and the optical voltage sensor 13 are connected to a thin wire 202.
Wired by. Also light method current.

Optical fibers 19 are connected from the voltage sensors 12 and 13 to external light emitting and receiving elements (not shown in FIG. 1).

Although FIG. 1 shows a structure in which the frame 14 is attached to the electric line 11 as a single piece, the distribution line is actually three-phase, and the same frame 14 is installed on each of the three electric lines. That will happen. For installation of the monitoring device on the electric line, the optical current sensor 12 housed inside is located in the air gap of the core for converging the magnetic field of circuit integration.

Taking these into consideration, as is clear from FIG. 2, the frame body 14 has a recess 22 for installing a live electric line, a core 15 for converging the magnetic field can be fixed, and a capacitor voltage divider 201 is installed. It has a built-in protrusion 10 and a base 14A. The four parts 22 of the frame 14 are connected to the electric line 11
, and insert the single-shaped pin body 17 as shown by the arrow 23 and fix it. The core gap core 15 is installed on the convex portion 14A of the fixed frame body 14 as shown by the arrow 24, and the screw body 16 for fixing the core is moved in the direction of the arrow 27 and coupled to the screw 28 of the frame body 14.

That is, a portion 26 of the screw body 16 is cut, and the screw body 16 is fitted into the electric line 11 using the portion 26, moved in the direction of the arrow 27, and screwed into the frame convex portion 14A. A current sensor and a voltage sensor are inserted and fixed into the frame 14 from below, and an optical fiber 19 is connected from each sensor.
A and 19B are exposed and are configured to enter a signal processing circuit (not shown). Further, the frame body 14 is configured to be covered with an overall cover 18 to protect the sensor section from the external environment.

Further, an example will be described using FIG. 2. FIG. 2 shows in detail the schematic diagram shown in FIG. 1 in a specific example of implementation, and is an exploded perspective view when it is fixed to an electric line.

Therefore, it is not shown in FIG. Whole cover and JL,
3. ; The screw body that fixes the core, the pin body that fixes it to the electric wire, etc. are shown. FIG. 2 shows a part of a distribution line monitoring device installed on a single tree power line 11. The device monitors the balance of the three-phase power lines, and the sensors installed on the three power lines are exactly the same. The distribution line monitoring device includes an optical current sensor 12, an optical voltage sensor 13,
A frame body 14 that accommodates those sensors, a magnetic field convergence core 1
6. Consists of a screw body 16 for fixing the core, a single-shaped pin body 17 for fixing the frame body 14 to the electric line 11, and a protective cover body 18.

The optical current sensor 12 and the optical voltage sensor 13 are guided into the interior of each sensor case body by an optical fiber 19, and the current sensor is passed through a Faraday element (inside the sensor). The voltage sensor passes through a Pockels element (inside the sensor). Such a current sensor 12 and voltage sensor 13
The storage section 20 provided in the sensor storage frame 14 from below
(partially not shown). The current sensor 12 is the frame body 1
It is inserted into the storage section 20 of No. 4 and installed so as to look into the core storage section 21. It goes without saying that it is better to install the current sensor 12 and voltage sensor 13 in advance in terms of workability, and also prevents displacement due to vibration. Note that the case may be further secured from below (not shown). The thing prepared in this way is installed from below the electric line 11 into the recess 22 formed in a part of the frame 1 to 1. The single-shaped insertion pin body 14 is inserted into the frame body 14 from the rear in the figure in the direction of arrow 23. This single-shaped insertion pin body 14 has a circumferential shape with the same thickness as the electric line 11, and fits perfectly with the electric line 11.

Naturally, the same shape is formed on the frame body in the portion that contacts the electric wire. It is conceivable that a part of the circumferential shape could be made to prevent the frame 14 from slipping laterally (
(not shown).

In this state, even if you put your hand forward from the frame 14, it will not fall and the subsequent work can be done easily.

Next, the magnetic field convergence core 15 is moved in the direction of the insertion arrow 24 from the arrow 24 in front of the frame and installed in the core storage section 21 .

At this time, the current sensors 12, which are inserted and fixed 1 to 1, are fitted into the air gap portion 2513 \-2 of the core 15 in advance. This core 15 is continuous except for the gap 25, and has a structure in which the magnetic flux is highly concentrated without interruption.

Next, a core fixing screw body 16 having a notch 26 in a part for fixing the core is fitted into the electric line 11 and inserted in the direction of the arrow 27, and the screwed core 15 is fixed by the screw portion 28. the gap in the core 15 and the voltage divider and sensor 12,
The positional relationship with 13 is set accurately.

In order to protect the integrated sensor section as described above, a protective cover 18 is placed over it from above. In addition, in this state, if there is a risk of moisture infiltration due to wind and rain, you may consider covering it from below.

With the above configuration and assembly, sensors are also installed on the other two electric lines. There is still a separate control box located in the middle of the utility pole (
3. In the above embodiments, the optical sensor is used as a voltage sensor (not shown).

Although we have described a device that accommodates two types of current, it is also possible to use either one, and the optical sensor also has a capacity of 14 g.
-9 may be based on another principle. ``Furthermore, the capacitor voltage divider, core, etc. are not essential, and the positions of some of them can be arbitrarily selected depending on the configuration.

Effect of the invention According to the present invention, the following effects can be achieved.

In other words, we have created a monitoring device that can perform optical current or voltage detection, maintain high insulation, and enable remote control by transmitting signals using twisted optical fiber cables.
It can be installed up to the point where the electric line is in a live state, and can be fixed by simply inserting a pin, etc. Moreover, it is easy to remove and does not affect the power distribution line system. Furthermore, the installation location of the current sensor or voltage sensor can be determined in advance within the frame, and there is no need to make any adjustments when installing it on the electric line. By attaching the magnetic field convergence core to the storage frame or installing the capacitor voltage divider inside the frame, there will be no deviation due to vibration, and the positional relationship between the sensor and the core or voltage divider can always be set accurately. It becomes possible to do 15-7.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view of the main parts of a distribution line monitoring device according to an embodiment of the present invention, Fig. 2 is an exploded perspective view of a distribution line monitoring device according to an embodiment of the present invention, and Fig. 3 is an optical current sensor. Figure 4 is the principle diagram of the optical voltage sensor. Figure 5 is the principle diagram of the optical voltage sensor.
The figure shows a conventional relay switch with a built-in zero-phase current transformer installed on a utility pole. 11...Electric line, 12...Optical current sensor, 13...Optical voltage sensor, 14...
... Sensor storage frame, 16 ... Core for magnetic field convergence, 16 ... Screw body for fixing the core, 17 ...
・1-shaped pin body, 18... Protective cover integrated.

Claims (2)

[Claims] (1) A sensor storage frame housing an optical current or voltage sensor is formed with a recess for installing an electric line, the electric line is inserted into the recess, and a fixing member is inserted into the recess. Distribution line monitoring equipment. (2) The distribution line monitoring device according to claim 1, characterized in that a magnetic field convergence core is attached to a part of the storage frame, and a capacitor voltage divider is installed inside the storage frame. (3) The arrangement according to claim 1, characterized in that a magnetic field convergence core is installed so that the electric line is located at the center, and an optical current sensor is located in the air gap of this core. Wire monitoring device.