JPS5813560Y2 - gas breaker - Google Patents

Description

[Detailed explanation of the idea] This proposal concerns the improvement of gas circuit breakers.

For example, a drive coil is installed in a 315 KV class gas breaker, and the cutoff current is commutated to the coil via the arc generated between the fixed and movable contacts when cutoff, and the interaction between the magnetic field from this coil and the arc itself. There are some types that self-extinguish the arc at the current zero point by driving the arc one rotation and cooling the arc column and attracting electrons by the relative speed with an arc-extinguishing insulating gas such as SF6 gas.

This proposal is applied to a gas breaker of this type, and the arc rotating surface of the electrode plate provided around the fixed contact is formed in a concave shape relative to the movable contact, thereby weakening the magnetic field for arc rotation. The aim is to increase the mechanical strength and alleviate the electric field between the movable contacts without causing any damage.

Fig. 1 shows an example of a conventional device, in which 1 is a fixed contact, 2 is a movable contact, 3 is an electrode plate whose outer tip is bent upward in the figure, and 4 is the fixed contact. A driving coil is electrically connected and mechanically disposed between the electrode plate 3 and the electrode plate 3, and the coil 4 is cast with a casting resin 5 using the electrode plate 3 as a casting container, for example. There is.

6 is a conductor, and 7 is an arc, which are housed in a container (not shown) filled with an arc-extinguishing gas 8 such as SF6 gas.

When the movable contact 2 moves in the direction of the arrow in response to the cutoff command and moves away from the fixed contact 1, an arc is generated between the two, but this arc easily transfers from the fixed contact 1 to the electrode plate 3, causing an arc. It becomes 7.

When the arc 7 moves to the electrode plate 3, a current flows through the drive coil 4 installed between the electrode plate 3 and the fixed contact 1, and a magnetic field H is generated.

The interaction between this magnetic field H and the arc 7 itself causes the arc 7 to be driven to rotate at high speed and extinguished at the current zero point.

When the current is commutated to the drive coil 4, the magnetic flux from the coil 4 passes through the electrode plate 3, so that an excessive electromagnetic repulsive force F acts on the electrode plate 3 as shown in FIG.

As a result, there is a drawback that the central portion of the electrode plate 3 undergoes plastic deformation and bulges toward the side opposite to the drive coil 4.

In order to deal with this, it is possible to increase the thickness of the electrode plate 3, but if this is done, the arc rotation surface of the electrode plate 3 will be 1
There is a drawback that the distance from the drive coil 4 weakens the magnetic field H, resulting in insufficient arc rotational force.

This proposal was devised in view of the above-mentioned points, and will be explained below based on FIG. 2.

In the figure, reference numeral 31 denotes an electrode plate having an arc rotating surface formed in a concave shape (bowl shape) so that the outer periphery is close to the movable contact 2 side. They are arranged so that the distance between them is approximately constant no matter where they are cast.

Reference numeral 41 denotes one drive coil, which is arranged in a concave shape along the electrode plate 31 (more specifically, along the back surface of the arc rotation surface).

The same parts as in Fig. 1 of the natural hair are indicated by the same reference numerals.

According to the present invention, the arc rotating surface of the electrode plate 31 is configured in a concave shape so that the outer periphery is close to the movable contact 2 and the distance from the movable contact 2 is approximately constant, and the fixed contact Since the drive coil 41 is wound in the radial direction of the electrode plate 31 and is arranged in a concave shape behind the arc rotation surface along the arc rotation surface, the mechanical strength of the electrode plate 31 is reduced without weakening the arc rotation magnetic field H in any way. It can significantly increase the strength and
Even if the movable contactor 2 moves away from the arc rotating surface of the electrode plate 31, the magnetic field acting on the arc does not decrease much.

Furthermore, since the distance between the movable contact 2 and the movable contact 2 is approximately the same no matter where on the electrode plate 31, the electric field between the movable contact 2 and the current cutoff/disconnection becomes equal and is relaxed. In addition to not causing any re-ignition, the structure is extremely simple and has extremely practical effects.

The electrode plate 31 is used as a casting container, and the drive coil 4 is inserted into the container.
When casting 1 side by side, it is convenient because it can be mounted extremely firmly.

According to the inventor's experiments, by adopting the configuration shown in Figure 2 for a 3/6'V class gas breaker, the plastic deformation limit can be roughly doubled, and the re-ignition voltage can be increased to about 1.5. It could be doubled.

[Brief explanation of drawings]

FIG. 1 shows a conventional device, and FIG. 2 shows an embodiment of the present invention, in which a is a vertical sectional view and b is a vertical sectional view of only the electrode plate. 1... Fixed contact, 2... Movable contact, 31...
Electrode plate, 41... Drive coil, 5... Casting resin, 8
...Insulating gas.

Claims (1)

[Scope of Claim for Utility Model Registration] ■ A movable contact and a fixed contact disposed in a container filled with an insulating arc-extinguishing gas, and an arc rotating surface attached to the fixed contact and described later in contact with the movable contact. an arc formed in a concave shape so that the distance between the movable contact and the movable contact, which is located in between and whose outer periphery is close to the movable contact and is pressed to the cutoff position, is approximately constant at any location; an electrode plate having a rotating surface, a button behind the arc rotating surface of the electrode plate and wound in the radial direction of the fixed contact, one end being connected to the fixed contact and the other end being connected to the electrode plate; A drive coil arranged in a concave shape, resting on the concave shape of the arc rotation surface,
A gas breaker consisting of: 2. The gas breaker according to claim 1, wherein the drive coil is cast behind the arc rotation surface of the electrode plate.