JPH05343206A - Apparatus for indicating fault of arrestor - Google Patents

Abstract

PURPOSE:To obtain an apparatus which has a long life time and is easily mounted on a steel tower, by using a sublimable material. CONSTITUTION:An apparatus for indicating the fault of an arrestor comprises a sublimable material 45, a movable body 44, and an indicating part 48. The sublimable material 45 is conductive, and it is connected electrically in series with a nonlinear element 30, and further, it is brought directly from a solid state to a gas when heathed. The movable body 44 continues to press down the sublimable material 45 usually, and it is energized by springs when the sublimable material 45 is vaporized. The indicating part 48 flies out a self-contained indicating cloth 50 being struck with the energized movable body 44, and it indicates the fact that an arrestor 60 fitted with a series gap is faulty.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for indicating a failure of a lightning arrester mounted on a transmission tower and installed from a transmission line through a series gap.

[0002]

2. Description of the Related Art FIG. 6 is a sectional view showing a structural example of a lightning arrester mounted on a steel tower. The lightning arrester 6 is formed by stacking a plurality of non-linear elements 30 containing zinc oxide as a main component and storing them in a container 31. The container 31 is composed of an insulating cylinder 32 and metal stoppers 33A and 33B screwed into both ends of the insulating cylinder 32, and the outer circumference of the container 31 is covered with a jacket 34 made of heat-shrinkable rubber. The laminated body of the non-linear element 30 is a holding metal fitting 35.
It is clamped by the compression spring 36 via. The grounding side terminal 6B is bolted to the metal plug 33B through the upper end of the jacket 34 at the upper portion of the lightning arrester 6. On the other hand, in the lower part of the lightning arrester 6, the non-grounded side terminal 6A has the support fitting 3
7, the support fitting 37 is screwed to the metal stopper 33A by the nut 38 via the lower end of the jacket 34. Further, the non-ground side terminal 6A is provided with a mounting bracket 6 for mounting an arcing horn, which will be described later.
C is fixed.

In FIG. 6, the inside of the container 31 is sealed by an outer cover 34. A fold similar to that of a general porcelain porcelain tube is provided on the outer side of the jacket 34 to improve salt damage resistance. A power supply lead (not shown) is interposed between the retainer fitting 35 and the metal stopper 33A. The lightning current from the power transmission line is transferred from the mounting metal fitting 6C to the non-ground side terminal 6A, the supporting metal fitting 37, the metal plug 33A, the power supply lead, the holding metal fitting 35,
The non-linear element 30 and the metal plug 33B flow in this order and reach the ground-side terminal 6B.

FIG. 7 is a side view showing a structural example in which a conventional fault arrester for a lightning arrester is mounted on a steel tower. An insulator 2 is suspended from a power transmission tower (not shown) through a support metal fitting 1 (at a ground potential), and a power transmission line 3 is stretched at its tip. A pair of arcing horns 4 at both ends of the insulator 2.
A and 4B are provided to form the discharge gap 5.
Further, the lightning arrester 6 shown in FIG. 6 is installed on the support fitting 1 via an insulating spacer 9. Another pair of arcing horns 7A and 7B are provided on the non-grounded side terminal 6A of the lightning arrester 6 and the power transmission line 3 to form a series gap 8.

In FIG. 7, a lightning arrester 6 absorbs an overcurrent when an overvoltage enters and prevents a follow current from flowing from the power transmission line 3. The arcing horn is for discharging the gap when an overvoltage such as a lightning surge enters the power transmission line 3 and absorbing the overvoltage. The gap length between the discharge gap 5 and the series gap 8 is such that when the overvoltage reaches the transmission line 3, the series gap 8
Is set to discharge faster. Since the gap alone does not have the ability to block the follow-up current from the power transmission line 3, the ground fault continues and a power transmission failure occurs. To prevent this, a lightning arrester 6 is provided via a series gap 8. When an overvoltage is generated in the power transmission line 3, the series gap 8 is discharged and the discharge current flows through the lightning arrester 6. Since the lightning arrester 6 cuts off the discharge current instantaneously (0.5 to 1.0 cycle), the follow-up current due to the ground fault is suppressed. Recently, instead of the arcing horns 4A and 4B, it is becoming more common to install the lightning arrester 6 together with the arcing horns 7A and 7B.

The failure indicator of the lightning arrester 6 is very important for detecting whether the lightning arrester 6 is operating normally when it receives an overvoltage. If the lightning arrester 6 is out of order, the follow-on current from the power transmission line 3 continues to flow as described above, making it impossible to transmit power and damaging the devices connected to the system. FIG. 8 is a cross-sectional view showing the detailed configuration of the arrester failure display device of FIG. The current transformer 11 is composed of an iron core 14 which penetrates the conductor 10 in its window, and a winding 15 wound around the iron core 14, and its output 11S.
Are sent to the detector 12. The detector 12 includes an electric circuit 16 for converting the output 11S of the current transformer 11 into a pulse voltage, a container 17 having one opening, and a lid 18. In this container 17, an explosive container 2 further filled with explosive 19
0 and a long strip-shaped display cloth 13 are stored.

In FIG. 8, when a ground fault current flows through the conductor 10 for a predetermined time or longer, the electric circuit 16 injects a pulse voltage into the explosive container 20. The explosive powder 19 is set to explode by this injection energy, and the explosive container 20 is provided with a gas outlet 21. The gas blown out by the impact of the explosion pushes the lid 18 open, so that the display cloth 13 jumps out of the container 17.

The apparatus shown in FIG. 8 is installed in a steel tower as shown in FIG. The grounding side terminal 6B of the lightning arrester 6 and the support fitting 1 are conductively connected by a conductor 10, and a current transformer 11 is interposed in the conductor 10. The output of the current transformer 11 is sent to the detector 12, and when the lightning arrester 6 fails, the display cloth 13 hangs down as shown in FIG. The presence or absence of this indicator cloth 13 was detected from the lower part of the steel tower by the observer with binoculars to detect the failure of the arrester 6. The insulating spacer 9 serves to insulate the ground side terminal 6B from the support fitting 1 so that all the current flowing from the ground side terminal 6B to the support fitting 1 passes through the conductor 10. The entire support fitting 1 may be configured to pass through the current transformer 11. However, this requires that the window of the iron core 14 of the current transformer 11 be made large, which increases the size of the current transformer 11.

[0009]

However, the conventional failure display device as described above has a problem that it needs to be replaced in 3 to 5 years because it uses explosives.
In other words, the explosive performance in the detector changes if the seal of the explosive container is not made strict, because it chemically changes with time. The life of the explosive can be maintained considerably if it is tightly sealed with a metal like a bullet, but an electrode (not shown) for injecting a pulse voltage into the explosive container 20 is inserted as shown in FIG. It is necessary, and the outlet 21 is also provided. Due to such a complicated structure, it is very difficult to completely seal the explosive container 20 from the outside air. Therefore, the reliability cannot be guaranteed unless the detector 12 is replaced within 3 to 5 years.

Further, since the conventional device requires an electric circuit, not only the structure is complicated, but also the installation on the tower is not easy. The existing lightning arrestor requires modification of the support bracket 1, and the insulating spacer 9 and the conductor 10 are required.
I also had to add. Furthermore, since the insulating spacer 9 also receives the load of the lightning arrester 6, it must be constructed so that its mechanical strength can be sufficiently secured. for that reason,
A considerable amount of modification cost was required to attach the conventional failure display device to the steel tower.

It is an object of the present invention to provide a device which has a long life and is easily attached to a steel tower by using a sublimable substance.

[0012]

In order to achieve the above object, according to the present invention, a lightning arrester in which a laminated body of a plurality of nonlinear resistance elements is housed in a container and is installed from a transmission line through a series gap A device for indicating the failure of, having electrical conductivity and electrically connected in series to the laminate,
A sublimable object that directly turns into a gas when heated, a movable part that constantly presses this sublimable object and is urged when the sublimable object is vaporized, and by being struck by this movable part The built-in display body pops out and the display unit displays that the arrester has failed.

In such a structure, the sublimable object and the movable part are housed inside the container, the display part is attached to the outside of the container, and the movable part penetrates through the through hole provided in the container. Shall be equipped with a striking part,
In addition, the sublimable material is a polycaproamide (Polycaproamido).
de) is made of a conductive composite material modified to be conductive.

[0014]

According to the present invention, a sublimable substance connected in series with a non-linear element, a movable part that is urged when the sublimable substance is vaporized, and a display part having a display body that pops out by the movable part are provided. Composed. When the lightning arrester fails, the temperature of the sublimable object rises due to the ground fault current from the transmission line, and the sublimable object is vaporized. When the sublimable object vaporizes in the movable part, the object that has been constantly pressed until then disappears, and the supporting part is lost, and the accelerating motion starts. The urging of the movable part causes the display part to be struck, and the display part pops out a display body such as a display part that displays a failure of the arrester. By visually checking the presence or absence of this indicator from the lower part of the tower, it is possible to confirm the failure of the arrester.

Further, the sublimable substance and the movable body are built in the container, and the display unit is attached to the outside of the container. The movable unit includes a striking unit that strikes the display unit by penetrating a through hole provided in the container. With this configuration, since the failure display device is all attached to the lightning arrester side, it is easy to attach to the steel tower. Further, the sublimable body is formed of a conductive composite material obtained by modifying polycapramide to be conductive. As a result, the sublimable object is mechanically sturdy even when it is constantly pressed, and the reliability of the failure display device is improved.

[0016]

EXAMPLES The present invention will be described below based on examples.
FIG. 1 is a cross-sectional view of essential parts showing the structure of a fault display device for a lightning arrester according to an embodiment of the present invention. The failure display device includes a movable portion 44, a sublimable object 45, and a display portion 48. Metal movable part 4 into which a striking part 47 made of an insulating cylinder is screwed
4 and the ring-shaped sublimable object 45 are housed in the container 40 of the lightning arrester 60. On the other hand, the display unit 48 includes a hanging strap 49 having one end fastened to the support fitting 37, a display cloth 50 that is a long strip of cloth, and a case 51 that folds and stores the display cloth 50, and the case 51 is a container. It is adhered to the metal stopper 43B on the lower side of 40. The metal stopper 43B has
A through hole is provided and a hitting portion 47 is inserted. Also,
The packing 46 for sealing the inside of the container 40 is
It is arranged between the striking part 47 and the metallic 43B. Further, a slight gap is secured between the tip of the striking portion 47 and the case 51. The compression spring 42 constantly presses the nonlinear element 30 via the insulating ring-shaped insulating retainer 39, and the compression spring 41 always presses the sublimable object 45 via the movable portion 44. A power supply lead (not shown) is interposed between the movable portion 44 and the press fitting 35. Other configurations are the same as those of the lightning arrester 6 of FIG. The same parts are designated by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, the sublimable substance 45 is a solid having conductivity at all times. When a large current flows through this sublimable substance 45, the sublimable substance 45 is heated by its resistance loss, and when it reaches the sublimation temperature, it vaporizes directly from the solid state.
An example of this type of material is conductive plastic, for example. In recent years, plastic materials have undergone a great progress in modification technology for imparting conductivity to themselves for the purpose of protecting ICs from damage due to static electricity or electrostatic charge. As a modification method, conductive carbon black, a metal filler, or the like is compounded with plastic to form it.

Such a conductive composite material is mainly used in the IC-related packaging field (magazines, trays, containers, racks, cardboards, etc.), but the sublimable material 45 of the present invention is used.
Mechanically durable polycapramide as a material applicable to
(The product name is nylon 6 and is called Alamine in Japan)
There are some made conductive (for example, trade name DAIEL
EC EX1905A, manufactured by Dainippon Ink and Chemicals KK).
This material has a surface resistance of 8.6 kΩ and is electrically conductive. Tensile strength is as strong as 7.7 kg / cm ² . The compressive strength is also equal to or higher than the tensile strength value and does not deform even when constantly pressed.
When the polycapramide reaches the sublimation temperature, it is directly exposed to CO ₂ , CH
₄ , decomposes into low molecular weight gases such as NO ₂ .

The ground fault current due to lightning is shown in FIG. 1 as follows. , Then the non-linear element 30 in that order. The size of the sublimable object 45 is formed so that it sublimates itself when the lightning arrester 60 fails and the ground fault current flows for a predetermined time or longer. When the sublimable substance 45 is vaporized, the movable portion 44 is urged downward by the compression spring 41. At that moment, the striking part 47 slides and strikes the case 51. By this impact, the metal plug 43B and the case 51 are separated from each other, and the case 51 falls downward. This failure display device has a long service life because it does not use explosives as in the past.

FIG. 2 is a cross-sectional view of essential parts showing a state when the sublimable substance 45 of FIG. 1 is vaporized. The movable portion 44 is pushed downward, and the display portion 48 moves from the support fitting 37 to the hanging strap 49,
It is connected to the display unit 50 and the case 51 and hangs down. The case 51 is fixed to one end of the display cloth 50 so as not to drop to the ground. A failure of the lightning arrester 60 can be confirmed by the presence or absence of the display cloth 50 visually observed by the surveillance staff.

FIG. 3 is a side view showing a structure in which the device of FIG. 1 is mounted on a lightning arrester installed in a steel tower. The arrester 60 is directly attached to the support fitting 33, and the failure display device is provided on the non-grounded side terminal 60A of the arrester 60. Therefore, the insulating space on the steel tower, which was necessary for installing the conventional failure display device, is unnecessary. Even if a new failure display device is installed, no modification is required on the tower side. Since all the failure display devices are attached to the lightning arrester side, only the bolting of the grounding side terminal 6B is required for attachment to the steel tower, and the installation work at the site is easy.

FIG. 4 is a cross-sectional view of the essential parts showing the structure of the fault display device for the arrester according to another embodiment of the present invention. The failure display device includes a movable part 52, a sublimable object 53, and a display part 58.
Consists of. A metallic movable part 44 into which a striking part 57 made of an insulating cylinder is screwed, and a ring-shaped sublimable object 53 are housed in a lightning arrester 60 container 40. On the other hand, the display portion 58 is the hanging strap 5 whose one end is fastened to the support fitting 37.
9, a display cloth 61 that is a long strip of cloth, and a case 62 that folds and stores the display cloth 61, and the case 61 is bonded to the nut 38. A through hole is provided in the metal stopper 43B, and a hitting portion 57 is inserted therein. A slight gap is secured between the tip of the striking portion 57 and the case 61.
The compression spring 55 constantly presses the non-linear element 30 via the metallic metal retainer 54, the sublimable object 53, and the movable portion 52. A power supply lead (not shown) is interposed between the metal retainer 54 and the metal stopper 43B. Hitting part 5
A pressing plate 64 is attached to the lower end of 7 by a nut 63. Another compression spring 56 is interposed between the holding plate 64 and the metal stopper 43B. The other structure is the same as that of FIG.

The material, size and function of the sublimable substance 53 in FIG. 4 are the same as those described in FIG.
The ground fault current due to lightning is shown in FIG.
3, the movable part 52, the holding metal fitting 35, and the non-linear element 30 flow in this order. When the lightning arrester 60 breaks down and the sublimable object 53 vaporizes, the balance between the compression springs 55 and 56 is lost and the movable portion 52 is urged downward. At that moment, the striking portion 57 slides and strikes the case 61. By this impact, the adhesion between the case 61 and the nut 38 is peeled off, and the case 61 drops downward.

FIG. 5 is a cross-sectional view of essential parts showing a state when the sublimable substance 53 of FIG. 4 is vaporized. The movable part 52 is pushed downward, and the display part 58 moves from the support fitting 37 to the hanging string 59,
It is connected to the display cloth 61 and the case 62 and hangs down. The presence or absence of the display cloth 61 can be visually inspected by an observer to confirm the failure of the arrester. The configuration in which the lightning arrester on the tower is provided with the device of FIG. 4 is exactly the same as that of FIG.

[0025]

As described above, the present invention provides a sublimable object which is electrically conductive and is connected in series with a non-linear element,
A movable part that is urged when this sublimable object vaporizes,
The display unit is provided with a display body such as a display cloth that pops out by the movable unit. When the lightning arrester breaks down, the display body of the display section pops out, so it is possible to confirm the presence or absence of the display body from the lower part of the tower. Therefore, the explosive charge required in the conventional device becomes unnecessary, and the device has a long life.

Further, in the apparatus of the present invention, the sublimable body and the movable body are built in the container, and the display section is attached to the outside of the container. The movable unit includes a striking unit that strikes the display unit by penetrating a through hole provided in the container. With this configuration,
Since all the failure display devices are mounted on the side of the lightning arrester, the insulating spacer on the steel tower, which was necessary for installing the conventional failure display device, is unnecessary. Since it is not necessary to support the entire arrester with an insulating spacer, it is mechanically robust. Also, even if a new failure display device is installed, no modification is required on the steel tower side. Installation on the steel tower is only by bolting the grounding side terminal 6B, which facilitates on-site installation work.

Further, the sublimable body is formed of a conductive composite material obtained by modifying the polycapramide to be conductive. As a result, it is possible to provide a highly reliable failure display device which is mechanically sturdy even when the sublimable object is constantly pressed.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing the configuration of a lightning arrester failure device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of essential parts showing a state when the sublimable substance of FIG. 1 is vaporized.

FIG. 3 is a side view showing a configuration in which the device of FIG. 1 is mounted on a lightning arrester installed on a steel tower.

FIG. 4 is a cross-sectional view of an essential part showing the configuration of a lightning arrester failure device according to a different embodiment of the present invention.

5 is a cross-sectional view of essential parts showing a state when the sublimable substance in FIG. 4 is vaporized.

FIG. 6 is a cross-sectional view showing a configuration example of a lightning arrester mounted on a steel tower.

FIG. 7 is a side view showing a configuration example in which a conventional arrester failure display device is attached to a steel tower.

FIG. 8 is a cross-sectional view showing the detailed configuration of the fault arrester of the lightning arrester of FIG.

[Explanation of symbols]

 2 Insulator 3 Transmission line 4A Arcing horn 4B Arcing horn 7A Arcing horn 7B Arcing horn 5 Discharge gap 8 Series gap 60 Lightning arrester 60A Non-grounding side terminal 6C Mounting bracket 33 Supporting bracket 37 Supporting bracket 30 Non-linear element 32 Insulation cylinder 43B Metal plug 40 Container 39 Insulated presser 54 Metal presser 35 Presser metal fitting 34 Outer cover 38 Nut 63 Nut 44 Movable part 52 Movable part 45 Sublimable object 53 Sublimable object 46 Packing 47 Hitting part 57 Hitting part 48 Display part 58 Display part 49 Hanging string 59 Hanging string 50 indicator cloth 61 indicator cloth 51 case 62 case 64 pressing plate 41 compression spring 42 compression spring 55 compression spring 56 compression spring

Claims (3)

[Claims] 1. A device for accommodating a laminate of a plurality of non-linear resistance elements in a container and displaying a failure of a lightning arrester installed from a power transmission line through a series gap, said laminate having conductivity. Is electrically connected in series to a sublimable substance that directly becomes a gas when heated, and a movable part that constantly presses the sublimable substance and is urged when the sublimable substance vaporizes. A failure arrester for a lightning arrester, comprising: a display unit that causes a built-in display body to pop out by being struck by a movable portion, and displays that the lightning arrester has failed. 2. The through-hole according to claim 1, wherein the sublimable object and the movable part are housed inside the container, the display part is attached to the outside of the container, and the movable part is provided in the container. A fault arrester for a lightning arrester, comprising a striking portion that penetrates through the display portion and strikes the display portion. 3. The fault display device for a lightning arrester according to claim 1 or 2, wherein the sublimable body is formed of a conductive composite material obtained by modifying polycapramide to be conductive.