JP3299584B2 - Arrester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightning arrester, and more particularly to a structure of a carbon trigger wire provided on a ceramic cylinder of the lightning arrester.

[0002]

2. Description of the Related Art A lightning arrester is formed by brazing and sealing an earth electrode and a line electrode to an end face of a ceramic cylinder, and sealing an inert gas such as an argon gas therein. When a surge enters from above, a discharge occurs between the line electrode and the ground electrode to protect the electrical equipment from external surges. Therefore, in order for the lightning arrester to exhibit a reliable protection function, it is necessary to reliably discharge in response to an external surge of a predetermined voltage or more, and a standard such as a discharge starting voltage is defined.

FIG. 4 shows a ceramic cylinder 1 used for a lightning arrester.
Indicates 0. The ceramic cylinder 10 is formed in a cylindrical shape as shown in the figure by a ceramic body, and is configured so that a carbon trigger wire 12 is provided on the inner wall thereof. In general, a lightning arrester is provided with a carbon trigger line in order to increase the response speed to a surge and to stabilize the discharge starting voltage of the lightning arrester.

The carbon trigger line 12 is provided by drawing from the end face of the ceramic cylinder 10 to the opposite end face as shown in the figure, and the carbon trigger wire 12 is provided shortly before reaching the opposite end face.
The tip of is stopped. FIG. 5 shows a state where the ceramic cylindrical body 10 is developed. FIG. 5 (a) shows an example in which four carbon trigger lines 12 are provided, and FIG. 5 (b) shows an example in which eight carbon trigger lines 12 are provided. It is formed so as to be pulled out from the end face in a different manner. The carbon trigger wire 12 is used to easily generate a discharge between the surge arrester and the electrode when an external surge enters the surge arrester, thereby improving the response speed to the external surge. Normally, when a carbon trigger line is provided, the carbon trigger line is formed on the inner surface of the ceramic cylinder 10 in the manner of drawing with a pencil.

[0005]

By the way, it is effective to increase the number of carbon trigger wires in order to increase the response speed to the surge applied to the lightning arrester.
As the number of carbon trigger lines increases as shown in the figure, the distance between adjacent carbon trigger lines decreases.
As a result, there has been a problem that insulation failure is likely to occur between the carbon trigger wires due to the influence of sputtering when the arrester discharges. When the lightning arrester discharges, the electrode material is sputtered and adheres to the inner wall of the ceramic cylinder. Therefore, the narrower the interval between the carbon trigger wires, the worse the insulation between the carbon trigger wires.

[0006] Insulation failure occurring between the carbon trigger lines due to discharge of the arrester affects the durability of the arrester, and those which are likely to cause insulation failure between the carbon trigger lines have low durability. . In the case where the carbon trigger wire is provided on the lightning arrester, the present invention can suppress the influence of the sputtering caused by the discharge of the lightning arrester and maintain a suitable insulating property between the carbon trigger wires, thereby providing a sufficient durability. Can be obtained,
An object of the present invention is to provide a lightning arrester having excellent characteristics with a fast response speed.

The present invention has the following arrangement to achieve the above object. That is, one end of the ceramic cylinder is grounded.
Avoid two or three poles where the line electrode is sealed to the pole and the other end.
In the detonator, the ceramic cylinder is provided on the inner surface of the ceramic cylinder.
From one end to the other end of the
A group of carbon trigger lines provided in parallel with the trigger lines
And from the other end of the ceramic cylinder toward one end.
A car with several carbon trigger lines placed in parallel
A predetermined distance in the circumferential direction of the ceramic cylinder
It is characterized by being provided alternately at intervals.

[0008]

The number of carbon trigger lines of the same electrode can be increased by forming a carbon trigger line group in which a plurality of carbon trigger lines are drawn close to each other, thereby improving the response speed of the arrester. it can. Furthermore, since the interval between the carbon trigger wire groups of different electrodes can be widened, it is possible to effectively prevent the occurrence of insulation failure between the carbon trigger wires due to sputtering when the arrester discharges.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is an explanatory view showing a state in which a ceramic tube portion is developed in a lightning arrester according to the present invention.
The arrester according to the present invention is also formed by alternately drawing the carbon trigger lines 12 from the opposite end faces of the ceramic cylinder as in the conventional example. The drawn carbon trigger line group is provided alternately from each end face facing in the circumferential direction.

The embodiment shown in FIG. 1 (a) is an example in which a carbon trigger line group is formed by two carbon trigger lines 12 each, and is provided by four carbon trigger line groups. FIG. 1B shows an example in which a carbon trigger line group is formed by three carbon trigger lines 12. 1 (c) and 1 (d) are examples formed by two carbon trigger lines, FIG. 1 (c) is an example formed by four carbon trigger lines 12, and FIG. This is an example formed by carbon trigger lines 12.

As shown in FIG. 1, if the carbon trigger lines are formed by bringing the carbon trigger lines close to each other, the number of carbon trigger lines provided on the inner wall surface of the ceramic cylinder 10 can be increased, and the carbon trigger lines can be increased. Since it is possible to increase the space between the groups of wires, it is possible to effectively prevent the occurrence of insulation failure between the carbon trigger wires due to sputtering when the arrester discharges.

FIG. 2 and FIG. 3 show the results of actual discharge tests performed with a lightning arrester of the type shown in FIG. 1 (a) provided with two carbon trigger wires. Fig. 2 shows an AC test of 5 amps (5 times / 1 second) at 3 minute intervals, and DC (2 KV / s)
It is a measurement of the voltage and the firing voltage at the impulse voltage (500 V / μs). In the figure, DC is DC voltage test, IM
P indicates the result of the impulse test. The maximum value, the minimum value, and the average value of the discharge starting voltage are shown, respectively. The left side of the figure shows the measured values at the start of the test, and the right side shows the measured values at the end of the life test. FIG. 3 shows a surge current waveform of 8/20 μs, 5KA (± 5
FIG. 10 shows the results of measuring the discharge start voltage at the DC voltage and the impulse voltage when the voltage was applied 10 times. The measured values at the start of the test and at the end of the life test are shown as in the above example.

The above-mentioned discharge test is the strictest test as a standard test for a lightning arrester, but the test results maintain almost the same performance at the end of the test as at the start of the test. Insulation between the carbon trigger wires is sufficiently maintained by the above, and the discharge start characteristics suitable for the impulse test showing the response speed of the arrester are maintained. A good test result was obtained in which no deterioration occurred.

Since the surge arrester of this embodiment is formed by performing an operation of drawing a plurality of carbon trigger lines close to the inner wall surface of the ceramic cylinder, it is necessary to draw a carbon trigger line as compared with the conventional surge arrester. Although it takes a long time, there is an advantage that the conventional device can be used as it is, and the excellent performance that cannot be obtained with the conventional product that can improve the response speed by maintaining the insulation between the carbon trigger wires can be achieved. Obtainable. In the above description, a two-pole lightning arrester has been described as an example. However, it is of course possible to similarly apply to a three-pole lightning arrester. In addition, the number of carbon trigger lines provided in the carbon trigger line group, the number of carbon trigger line groups, and the like may be appropriately set according to product specifications such as a discharge starting voltage.

[0015]

According to the lightning arrester according to the present invention, as described above, the response speed to an external surge can be improved, and insulation failure between the carbon trigger wires due to sputtering when the lightning arrester discharges. It is possible to effectively prevent the occurrence of such a phenomenon, and it is possible to obtain a lightning arrester having excellent characteristics.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a ceramic cylinder body of a lightning arrester in a developed state.

FIG. 2 is a graph showing a discharge endurance test result of a lightning arrester by applying an AC voltage.

FIG. 3 is a graph showing a discharge endurance test result of a lightning arrester by applying a current surge.

FIG. 4 is an explanatory view showing a configuration of a ceramic cylinder of a lightning arrester.

FIG. 5 is an explanatory view showing a developed ceramic cylinder of a conventional arrester.

[Explanation of symbols]

 10 Ceramic cylinder 12 Carbon trigger wire

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01T 4/10-4/12 H01T 2/02

Claims (1)

(57) [Claims] An earth electrode is provided at one end of a ceramic cylinder.
For 2-pole or 3-pole arresters with line electrodes sealed at the ends
The ceramic tube is provided on the inner surface of the ceramic tube.
Multiple carbon triggers from one end of the body to the other
A group of carbon trigger lines, which are arranged in parallel and
From the other end of the ceramic cylinder toward one end,
A carbon trigger line with the carbon trigger line
The rigged wire group is spaced at a predetermined interval in the circumferential direction of the ceramic cylinder.
A lightning arrester characterized by being provided alternately .