JPS587234B2 - Hirai Kino Gear Tsupusouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gap device for a lightning arrester applicable to DC power transmission.

In power systems, lightning arresters are responsible for absorbing abnormal voltages such as lightning surges and switching surges, and then restoring the system to its original state.

For example, as shown in FIG. 1, a lightning arrester Ar.
is connected.

This lightning arrester Ar. is constructed by connecting gap elements G and characteristic elements T in multiple stages.

Recently, there has been a trend toward higher voltages in electric power systems, and as a result, handling of surge arresters has become increasingly difficult.

In other words, the energy processed by the lightning arrester is 1/2CV2 (c:
Line capacitance (■: switching surge voltage value) is proportional to the square of the voltage and requires a lightning arrester that can handle a large amount of energy.Also, in the case of a lightning arrester for DC power transmission, if the cable line is long, In many cases, lightning arresters must withstand heavy duty.

In order to satisfy these requirements, a pair of main electrodes and an auxiliary electrode are provided in the arc extinguishing chamber, and an auxiliary electrode is provided opposite to the main electrode, and a groove is provided on the arc extinguishing plate where the auxiliary electrode is located. We have developed a lightning arrester equipped with a re-ignition gap, which divides the arc during re-ignition into two and separates the discharge start point from the re-ignition point.

In a lightning arrester with this configuration, the arc does not stagnate in one place during high current, so there is very little damage to the arc extinguishing plate, and insulation recovery is easy because the discharge initiation part and the re-arculation part are separated. The results are good, and there is no fear that the discharge start characteristics will change.

However, in order to realize the gap element in this lightning arrester, the upper arc-extinguishing plate and the lower arc-extinguishing plate must be perfectly fitted.

A particularly important point is to eliminate the gap between the auxiliary electrode and the upper arc-extinguishing plate.

However, since this arc-extinguishing plate is a fired ceramic product, there are dimensional variations such as warpage after firing, and it is inevitable that some gaps will occur.

If there is a gap between the auxiliary electrode and the upper arc-extinguishing plate in this way, the ionized hot gas, which should originally be supplied only to the groove, is supplied through this gap, resulting in stable re-ignition. You won't be able to have sex.

In some cases, the supply of ionized hot gas from this gap may increase, causing a problem in which the re-ignition cannot be stopped and there is a possibility that the circuit cannot be shut off.

The object of the present invention is to prevent the supply of ionized hot gas from the gap between the auxiliary electrode and the arc-extinguishing plate, which cannot be avoided in manufacturing, by blocking the gap. The goal is to provide the following.

The present invention will be explained below with reference to FIGS. 2 to 7.

The lightning arrester of the present invention is hermetically housed in a tube in which discharge gap elements and characteristic elements are connected in multiple stages.

As shown in FIGS. 2 and 3, this discharge gap element 10 has an arc extinguishing chamber 13 formed by stacking disc-shaped arc extinguishing plates 11 and 12 made of an insulating material such as ceramics.

This arc-extinguishing plate 11 is not shown in FIG. 2, but is shown by a dotted line in FIG. 3.

Inside this arc extinguishing chamber 13, an auxiliary electrode 16 is provided opposite to the main electrodes 14 and 15.

Grooves 17a, 17 are formed on the surface of the arc-extinguishing plate 12 facing the auxiliary electrode 16.
b.

In this inverted T-shaped auxiliary electrode 16, a groove portion 18 consisting of an inverted T-shaped horizontal groove 18a and a vertical groove 18b is located along the center of the electrode surface on the opposite side to the grooves 17a and 17b provided in the arc-extinguishing plate 12.
5a is provided in this groove 18 as shown in FIG. 4.
A thin pipe 1 with a slit 20 in the side shown in , b
9a and 19b are provided in a T-shape.

As shown in FIGS. 6 and 7, pipes 19a and 19b
One end of the slit 20 is bonded or soldered to the grooves 18a and 18b to form an ionized hot gas blocking member 21.

When the arc extinguishing plate 11 is placed like a lid on the arc extinguishing plate 12 provided with the auxiliary electrode 16 formed in this state and pressed, the pipes i9a and 19b of the blocking member 21 are provided with slits 20. Therefore, the gap between the auxiliary electrode 16 and the arc-extinguishing plate 11 is completely closed, and the arc-extinguishing plates 11, 1
2 are glued at their respective edges to discharge gap element 1
0 is formed.

The operation of the present invention will be explained.

For example, when a lightning serge enters this arrester and exceeds the discharge starting voltage of the arrester, a discharge occurs at the discharge starting part 23 between the main electrodes 14 and 15, and the arc A is driven by the magnetic field of a driving coil (not shown) and extends. The arc A1 is divided into two, and the arcs B1 and B2 are separated between the auxiliary electrode 16 and the main electrodes 14 and 15.

Grooves 17a and 1 extend further like arcs D1 and D2.
When the foot of the arc reaches the auxiliary electrode 16 on the opposite side of the main electrode 7b, the ionized hot gas of this arc is supplied to the re-ignition section 24 through the grooves 17a and 17b.

When the current of the arcs D1 and D2 is large and the amount of hot gas is large, the withstand voltage of the re-ignition section 24 becomes low and the re-ignited arcs C1 and C2 are driven again.

In this way, when the arc current is large, the arc is re-ignited and the arc drive is repeated, and when the current becomes small, the auxiliary electrode 16
The legs of the upper arcs D1 and D2 are grooves 17at17b
Even if the arc reaches 1, the amount of hot gas supplied to the re-ignition section 24 decreases, and the arc legs of the arcs D1 and D2 remain in the groove 1 without re-ignition.
7a and 17b, the arc extends and is finally driven like arcs E, , E2, the arc voltage rises and the current is cut off.

A pipe 19 provided in this ionized hot gas blocking member 21
The same effect can be obtained by using a bending member 30 shown in FIG. 8 instead of as19b.

The pipes 19a, 19b or the bending member 30 are made of metal such as copper or aluminum.

As described above, according to the present invention, the ionized hot gas blocking member 2 provided on the auxiliary electrode when the arc extinguishing plates 11 and 12 are joined together
By crushing the first metal pipe 19at19b, the gap between the auxiliary electrode 16 and the arc-extinguishing plate 11 is completely eliminated.
Pass only through b.

Therefore, ionized gas is not freely supplied from the gap created between the auxiliary electrode 16 and the arc-extinguishing plate 11 as in the conventional case, and it is possible to provide a lightning arrester equipped with a discharge cap element that has stable re-ignition characteristics. .

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a power transmission line, Fig. 2 is a front view of a discharge gap element of a surge arrester according to the present invention, Fig. 3 is a cross-sectional view taken along line 3-3 in Fig. A front view of the auxiliary electrode, Figures 5a and 5b are side views and sectional views of the metal pipe, Figures 6 and 7 are sectional views taken along lines 6-6 and 7-7 in Figure 4, and Figure 8a and b are a side view and a sectional view of the folding member. 11, 12... arc extinguishing plate, 14.15... main electrode, 16...
...Auxiliary electrode, 17a, 17b...Groove, 21...Blocking member, 23...Discharge starting part, 24...Re-ignition part, A, A1,
B1, B2, C1, C2, D1, D2, E1, E2...
arc.

Claims (1)

[Claims] 1. An arc extinguishing chamber formed by stacking disc-shaped silencers made of insulators, a pair of main electrodes facing each other across a discharge gap provided in this arc extinguishing chamber, and a re-ignition gap between the two main electrodes. and a first ionized hot gas provided on a surface of the arc-extinguishing plate facing the auxiliary electrode that guides the ionized hot gas to the re-ignition gap.
a groove, a second groove provided on the auxiliary electrode surface opposite to the first groove, and a groove formed between the second groove and the arc-extinguishing plate provided opposite to the second groove. A gap device for a lightning arrester consisting of a metallic blocking member that closes a gap.