JPS60185320A - Vacuum breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] Is the present invention a main electrode? This invention relates to an improved parallel magnetic field type vacuum circuit breaker.

[Background of the invention]

Vacuum circuit breakers, which are often used in power distribution systems, have a very strong arc-extinguishing force, and there is a current rupture phenomenon in which the current suddenly changes to zero when the circuit is shut off in the small direction. ■It was easy to generate pressure. Therefore, conventionally, surge absorbers such as capacitors and arresters have been used in combination to insulate and protect equipment from this overvoltage. However, surge absorbers lose the advantage of vacuum circuit breakers, namely their small size. To deal with this, how can I omit the surge absorber due to the current level that causes the current cutting phenomenon? This can be determined by the electrode material.

Examples of electrode materials with low cutting current levels include composite materials such as cobalt (CO), silver (Ag), and selenium (Se). Composite tunken material? When used in a parallel magnetic field type main electrode, the main electrode has an electrode substrate made of non-oxidized steel, and adjacent to the electrode substrate made of Co, Ag.

A contact layer consisting of Se is used, and the two are brazed, e.g.
G-braze it and make it into one piece. [7] Because it contains Be, the brazing properties are poor.Therefore, when manufacturing the Co-Ag-Se material for the contact layer of the Co substrate, it is attached by sintering and the contact layer between the electrode and the substrate is It is conceivable to place it in a Zandermante shape and braze it.

However, when a Co substrate is used as the main electrode, C.

Since the substrate is ferromagnetic, it acts as a magnetic shield and
Due to this, effective parallel magnetic field sound cannot be generated in the space between the electrodes.

Also, what is the size of the contact part at the center of the main electrode? In the main electrode, which is constructed more than that of the outer circumferential part and has an improved cutting current level, the electrode material is made of CC01A and Se.Limiting to the contact part, the electrode material made of Co, Ag and Se is used to prevent arcing. The voltage is about 12V, and the electrode material for general vacuum circuit breakers, such as copper (Cu)-bismuth (Bi) (
c- Since the arc voltage of the outer circumferential part used was 17-20V, the arc could not be transferred from the contact part to the main electrode surface of the outer circumferential part, and the arc was concentrated only on the contact part. What is the blocking performance? It's not about getting it.

For this reason, vacuum circuit breakers for large current line breaks with small breaking currents have traditionally been rejected.

[Purpose of the invention]

The object of the present invention is to have a low cutting force level, which eliminates the need for a surge absorber, and which has a large molar capacity of 25 kA or more.
Is a vacuum circuit breaker suitable for I&C? It is about providing.

[Summary of the invention]

The main 'U4L pole of the present invention has a contact part made of cobalt, silver, and selenium in the medium heat part, and a cobalt/coat part around the contact part.
The above object is achieved by comprising an outer peripheral portion made of silver and tellurium.

[Embodiments of the invention]

Below are examples of the present invention? This will be explained using a vacuum circuit breaker l shown in FIG.

The vacuum box disconnector 1 is provided with a conductive rod 6.7 passing through four end plates 3° in a vacuum container consisting of an insulating cylinder 2 and end plates 3 and 4, and a pair of electrodes 8 and 9, respectively. , conductive rod 6. in a vacuum container. It is made up of HC fixed. One conductive rod 7 is hermetically sealed to the end plate 4 via a bellows 10i.

The four electric rods 6 are directly attached to the end plate 3 and hermetically sealed. Movable side and fixed 1! A cylindrical metal vapor shield 11 surrounding the l electrodes 8 and 9 is attached to the middle part of the insulating cylinder 2 by a shield support 12. The conductive rod 7 is operated by an operation mechanism (not shown).
is driven upward in the axial direction.

The movable side electrode 8 comes into contact with the identification side electrode 9, the vacuum circuit breaker becomes a closed circuit state, and as the conductive rod 7 is driven axially downward 4ii1, the movable side electrode 8 separates from the fixed side electrode 9 and the vacuum is interrupted. The device moves to the open circuit state.

These electrodes 8.91d are composed of a coil electrode 13 and a main electrode 14, but since the structure of both electrodes is the same, what is the explanation for the fixed side electrode 8? omitted, and the second for the movable electrode 9.
This will be explained using the diagram.

The coil electrode 13 has a center 1fi with 7 conductive rods fixed to the back surface.
16 arms extending from the center to the outer circumferential direction are attached to l15, and the arm 16 is attached to the center part 15 (I- an outer circumferential part 18 which extends in the circumferential direction so as to surround it and whose other end corresponds to the gap 17). (r, integrally formed in the arm portion 16. Connection portion 19
is provided at the other end of the outer periphery and is electrically connected to the main electrode 14.

The main electrode 14 has 20 eight linear slits extending from the outer periphery toward the center. The slit 20 is the conductive rod 7
The current flows through the coil electrode 13 and flows through the connection 19 to the arc 100 of the main electrode 14 and the coil electrode 1
3, a parallel magnetic field (not shown) 4 is generated. When a parallel magnetic field is applied to the 14 main electrodes, eddy currents flow in the main electrodes 14,
The eddy current can be reduced by the slit 20. For this reason, does the parallel magnetic field become depolarized by the magnetic field caused by the eddy current? You can do it with less.

As shown in FIG. 3, the structure of the main electrode 14 is such that one end of the electrode substrate 2, for example, non-oxidized copper, is connected to the connecting portion 19, and the other end surrounds the contact portion 23 and the contact portion via the Co substrate 22. With the outer peripheral part 24? They are fixed together by brazing. As shown in FIG. 4, the contact portion 23 may be formed into a ring-shaped contact portion 23A having 25 central grooves in the center. The height of the contact portion 23 is higher than that of the outer peripheral portion 24, and the electrode material of the contact portion 23 is made of Co, Ag, and Se. The component range of the contact part 23 is for Co: 20 to 80
(%), Ag 13-50 (punishment, S e it, t 7
It is comprised within the range of ~30(%).

The electrode material of the outer peripheral portion 24 is made of Co, Ag, and Te (tellurium). The component range at the outer periphery is Co
-1720~80(%), Agit l 8~72(
%), T e i: 5 to 22 (%).

According to this configuration of the main electrode 14, the Co substrate 22 is limited to the contact portion 23, the magnetic shielding effect of the Co substrate 22 is small, and most of the inter-electrode space is effectively parallel to the outer peripheral portion 24. Can generate magnetic field sound. On the other hand, as shown in FIG.
The arc 100 ignited smoothly moves to the outer peripheral portion 24, and the contact portion 23 is not melted and damaged, and the arc 100 can be improved.

As shown in FIG. 5(B), the rupture current (I) between the contact portion 23 and the outer peripheral portion 24 is higher in the outer peripheral portion 24 than in the contact portion 2.
Slightly larger than 3. Therefore, the arc 100 ignited in the outer circumferential portion 24 at the time of interruption is quickly extinguished by the contact portion 23. It is because the vapor pressure of Te is lower than that of Se (, T
e1j: Since it evaporates faster than Se, the arc 100 is extinguished at the outer peripheral part 23 earlier than the contact part 23, and then
Since the current is ignited, the current is extinguished at or near the current zero point. Therefore, as shown in FIG. Since the surge voltage (V) can be reduced, the present invention eliminates the need to use a conventional surge absorber, making it possible to downsize the vacuum circuit breaker.

In this embodiment, the four magnetic field generating parts consisting of the arm part and the outer peripheral part use coil electrodes that generate parallel magnetic field sound in the same direction (also, two symmetrically arranged magnetic field generating parts of the four magnetic field generating parts A coil electrode may be used which generates parallel magnetic fields in different directions, or a coil electrode may be used which is wound around a coil outside the vacuum container.

[Effects of the Invention] As described above, according to the vacuum circuit breaker of the present invention, the generated surge is small. This is no longer necessary and the vacuum circuit breaker can be made smaller.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a vacuum circuit breaker shown as an embodiment of the present invention, FIG. 2 is a perspective view of the movable side electrode used in FIG. 1,
3 is a side sectional view of FIG. 2, FIG. 4 is a side sectional view of an electrode as another example, and FIGS. 5(A) and 5(B) are characteristic diagrams of arc voltage and cutting current. 2... Vacuum vessel, 8 and 9... Fixed side and movable side electrodes, 13... Coil electrode, 14... Main electrode, 2
3...Contact part, 24...Outer peripheral part.

Claims (1)

[Claims] 1. At least one pair of piezo electrodes that can be freely brought into contact and separated from the vacuum container?
In a vacuum circuit breaker which applies a parallel magnetic field to the main electrode, the main electrode has a contact part made of cobalt, silver and selenium in the center, and an outer peripheral part made of cobalt, silver and tellurium around the contact part. Vacuum circuit breaker with features: 2. Does the main electrode have the contact part and outer peripheral part on the electrode substrate? Arrangement L % The vacuum according to claim 1, characterized in that the outer circumferential portion and the electrode substrate are integrally formed by brazing each other with a cobalt layer interposed between the contact portion and the electrode substrate. circuit breaker. 3. What is the height of the contact part? The vacuum circuit breaker according to claim 1 or 2, characterized in that the vacuum circuit breaker is constructed higher than that of the outer peripheral portion.