JPH0124334B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a gas insulated disconnector.

Conventional disconnectors were responsible for disconnecting and connecting the grid during no-load conditions, and only had to have the ability to switch on and off the charging current of the power transmission line. However, recently, as switchgear has become insulated with SF ₆ gas, load current switching capabilities have become required for disconnectors due to the need for equipment simplification and economical operation.

An example of this is the two systems A and B shown in Figure 1.
This is the disconnection of one system when the power supply side and load side of the power transmission bus are shared and a loop is formed.

In FIG. 1, when one of the systems is disconnected by opening the disconnector _D1 or _D2 , all current flows to the system on the side of the closed disconnector _D1 in the illustrated case.
Therefore, the voltage drop of the closed system is applied to the disconnector _D2 , which opens to cut off the current.

When the loop is long, the recovery voltage at the time of disconnection or disconnection increases, so the specifications for disconnection and disconnection duty become stricter. If the method does not involve spraying, the shearing ability will be insufficient.

In order to increase the disconnection capacity, some disconnectors use a buffer method, but the operating force is quite large, so it is not economical for small capacity. As a method that does not require an increase in operating force, there is a method in which the arc is rotationally driven by a magnetic field using an arc drive coil, thereby extinguishing the arc.

However, in this method, when the charging current is cut off and restrike occurs, a high surge voltage is applied to the coil. As a result, the insulation of the coil may be broken and a short circuit may occur. If the coil is shorted, the loop current will be shunted and there will not be enough magnetic field to rotate the arc.

The present invention was made in view of the above circumstances, and has a simple structure and excellent loop current breaking performance.
Another object of the present invention is to provide a gas-insulated disconnector having a structure that protects the coil from overvoltage when the charging current is cut off and can maintain the cutting ability for a long time.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 2 is a diagram for explaining the overall structure of a gas insulated disconnector according to an embodiment of the present invention, and the detailed structure of its main parts is shown in FIGS. 3a and 3b.

In FIG. 2, a fixed electrode part 3 is fixed inside the case 2 by an insulating spacer 3a supporting a conductor 4a, and is arranged opposite to the fixed electrode part 3 inside a cylindrical case 2 filled with an insulating gas 1. movable electrode part 5
is an insulating spacer 3b that similarly supports the conductor 4b.
Fix it to case 2 with. However, there are other methods of fixing the electrode parts 3 and 5, and the method is not limited to this method. A movable contactor 6 constituting a part of the movable electrode section 5 is connected to an operation mechanism section (not shown) via an insulator 7 and a link 8.

In addition, the energization paths during closing are 4a, 3, 6, 5,
The order is 4b.

FIG. 3 is an upper half vertical cross-sectional view showing the detailed structure of the fixed electrode part 3 and the movable contact part 6 shown in FIG. 2, and shows the state during closing.

Describing the detailed structure of the fixed electrode section 3, a contact base 32 is fixed to the fixed main current-carrying conductor 31. A fixed current-carrying contact 3 is mounted on the contact base 32.
3 is attached and comes into contact with a movable current-carrying contact 61 disposed opposite to the fixed current-carrying contact 33 so as to be able to freely come into contact with and separate from the movable current-carrying contact 61 .

In order to obtain the contact pressure at this time, a spring 34 and a spring cover 35 are attached to the upper part of the fixed current-carrying contact 33. Further, a fixed arc finger contact 36 is arranged concentrically inside the fixed current-carrying contact 33. Base 3 of fixed arc finger contact 36
6a is fixed to the fixed main conductor 31 with bolts 38. A movable arc finger contact 62 is provided concentrically inside the movable energizing contact 61 and comes into contact with the fixed arc finger contact 36 so as to be able to move toward and away from it.

The tip of the movable arc finger contact 61 is made of an arc-resistant member 62a in order to come into contact with the fixed arc finger contact 36, and an arc drive coil 62b formed in a cylindrical shape is provided at the intermediate outer periphery thereof. The arc drive coil 62b has one end connected to an arc-resistant member 62a.
The other end is electrically connected to the coil end ring 62c and is also structurally joined.

A cylindrical auxiliary member 62d made of an insulating material is provided on the inner surface of the arc drive coil 62b as an arc-resistant member 62.
a and the coil end ring 62c. Tooth-like protrusions 62e are provided on the arc-resistant member 62a and the coil end ring 62c that contact the inner surface of the auxiliary member 62d. Further, a gap is provided inside the auxiliary member 62d between the opposing surfaces of the arc-resistant member 62a and the coil end ring 62c,
An overvoltage protection gap 63 is formed electrically in parallel with the arc drive coil 62b.

The configuration between each contact is current-carrying contacts 33, 61.
After the arc contacts 36 and 62 are opened, the arc contacts 36 and 62 are opened.

Further, the fixed electrode section is provided with a shield 37 that covers the outer periphery of the side surface of the current-carrying contact 33.
Further, FIG. 3a is an enlarged view of the fixed arc finger contact 36 viewed from the direction of the arrow shown in the figure. As shown in FIG. 3b, the fixed arc finger contact 36 is formed into a finger shape by providing a plurality of grooves 36b in the axial direction, so that contact pressure can be obtained by the spring property.

FIG. 4 is a diagram showing a state in which the gas insulated disconnector according to the present invention is in an open state.

Fixed arc contactor 36 and movable arc contactor 62
The arc 30 generated between the arc-resistant members 62a is rotationally driven by the magnetic field generated by the arc drive coil 62b. This enhances the cooling effect. That is, the illustrated magnetic flux φ has a component orthogonal to the arc 30, and its value can also be set large.

The arc 30 is cooled by the above action and extinguished at the current zero point. By the way, when the charging current is interrupted and restarted, a high surge voltage is applied to the arc drive coil 62b. However, due to the discharge of the overvoltage protection gap 63 provided between the opposing surfaces of the arc-resistant member 62a and the coil end ring 62c and inside the auxiliary member 62d, no surge voltage is applied to the arc drive coil 62b. The insulation of 62b will be protected. Furthermore, since the arc finger contacts 36 and 62 are provided inside each of the energizing contacts 33 and 61, the arc 30 can be generated at a position away from the case 2, thereby reducing the occurrence of short circuit accidents. can do. On the other hand, since a large electromagnetic force acts on the arc drive coil 62b due to the current, if the strength of the coil is not sufficient, the arc drive coil 62b
b will suffer mechanical damage.

However, in the present invention, since an auxiliary member made of an insulating material is attached to the inside of the arc drive coil 62b, it can sufficiently withstand large electromagnetic forces that act when the current is interrupted.

As explained above, according to the present invention, it has a simple structure and excellent loop breakage performance, and when the charging current stops, the arc drive coil can be protected from overvoltage and the breakage ability can be maintained for a long time. A gas insulated disconnector having a structure can be provided.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining a disconnector placed in a system and charged with loop current switching responsibilities, FIG. 2 is a schematic configuration diagram of a gas-insulated disconnector according to an embodiment of the present invention, and FIG.
4 and 4 are detailed views of the main parts of the gas insulated disconnector shown in FIG. 2, and are diagrams showing a state in which the contact is being opened and a state in which the contact is being opened. 1... Insulating gas, 2... Cylindrical case, 33...
Fixed energizing contact, 36... Fixed arc finger contact, 61... Movable energizing contact, 62... Movable arc finger contact, 62a... Arc resistant member, 62
b...Arc drive coil, 62c...Coil end ring, 62d...Auxiliary member, 63...Gap for overvoltage protection.

Claims (1)

[Claims] 1. A fixed current-carrying contact in a cylindrical case filled with an insulating gas, a fixed arc finger-like contact placed inside the fixed current-carrying contact and electrically connected to the current-carrying contact, and the current-carrying contact. A gas insulated disconnector comprising: a fixed arc finger contact; and a movable arc finger contact disposed so as to freely come and go; and a movable arc finger contact disposed so as to freely come and go. In the device, the movable arc finger contact is arranged concentrically with the arc-resistant member forming the tip and the movable current-carrying contact, one side is electrically connected to the arc-resistant member, and the other side is electrically connected to the arc-resistant member. A coil end ring that is electrically connected to the movable current-carrying contact is provided with an arc drive coil that is electrically connected, and the coil end ring and the arc-resistant member are electrically connected in parallel with the arc drive coil. A gap is provided between opposing surfaces to form an overvoltage protection gap, and the arc drive coil is disposed on the outer periphery of an intermediate portion between the arc-resistant member of the movable arc finger contact and the coil end ring. A gas insulated disconnect switch characterized by having an auxiliary member made of insulating material attached to the inside.