JPS6036981Y2 - Particle trap for gas insulated equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the arrangement of particle traps in gas insulated equipment.

The insulation method used for connecting busbars between equipment, such as conduit aerial cables and circuit breakers and disconnectors, is a method in which IF 6 gas or the like is injected under pressure as an insulating medium.

For example, in the case of a conduit aerial cable that is press-fitted with SF6 gas, high voltage is applied to the conductor during power transmission, but despite the strict finishing during manufacturing, a small amount of conductor and insulation remains. Due to the above-mentioned fine particles and the above-mentioned fine particles generated by long-term use, a large discharge may occur between the conductor and the sheath from a weak local discharge during energization.

Such a phenomenon also occurs between conductors and cases in a small sealed substation space.

In order to avoid this, a particle trap is provided in a space such as a metal sheath or a casing that forms an outer wall with the conductor, and traps particles moving in the insulating gas to prevent discharge and the like.

As an example, let's take a conduit aerial cable. A hollow single-core or multi-core conductor made of aluminum or copper is inserted into a sheath made of aluminum or stainless steel plate by a highly insulative spacer made of epoxy injection product, etc. The sheath is supported and SF6 gas is pressurized into the sheath.

If power is transmitted under such conditions, the above-mentioned phenomenon may occur, so a particle trap is provided in the space created between the conductor and the sheath.

This particle trap is provided at various locations along the conduit cable line, but if the relative position of the trap and the spacer is not appropriate, it may lead to a decrease in insulation.

The present invention proposes a widely used arrangement of particle traps to solve these problems.

Next, one embodiment of the present invention will be described.

FIG. 1 is a cross-sectional view perpendicular to the length direction of the air conduit cable, and FIG. 2 is a cross-sectional view in the length direction.

The arrow in the figure indicates the direction directly above during installation.

When the columnar spacer 2 made of epoxy injection product etc. is installed,
The conductor 3 is fixed to the inner surface of a sheath 1 forming a metal outer wall so as to be directly above the conductor 3, and the conductor 3 is fitted into an annular portion formed by the other end of the columnar spacer 2 and supported by the columnar spacer 2.

Although only one spacer is shown in the figure, as the conduit extends, a columnar spacer is similarly attached at a position directly above the conduit when it is laid, and supports the conductor 3.

On the other hand, it extends inside the sheath 1 along the inner surface of the sheath 1 at a position directly above the conduit, that is, at a position on the opposite side beyond the conductor support part from the position where the spacer is attached, and A particle trapping electrode 5 made of a metal plate with many holes 4 drilled on its surface is supported by a support 6 so as to have the same potential as the sheath 1, and a space is created between the particle trapping electrode 5 and the sheath 1 facing it. A trap 7 is formed by this.

In this way, the traps 7 are provided corresponding to the fixed locations of the spacers 2 provided in the conduit, but such a configuration is required for each position of each columnar insulating spacer throughout the conduit. There's no need.

As I briefly explained earlier, fine particles floating in the insulating gas tend to move between the conductor and sheath toward the columnar insulating spacer made of dielectric material, and accumulate on the surface of the columnar insulating spacer. However, if such fine particles are semiconductive or conductive, they cause a flashover phenomenon on the surface of the columnar insulating spacer, causing insulation rupture.

Therefore, in the present invention, we pay close attention to the conductor support part by the spacer, where there is a high possibility of accidents occurring, and by providing a particle trap below the columnar insulating spacer, we can capture particles floating in this area with high accuracy, and It has the effect of eliminating the cause of.

In fact, the insulation distance is not shortened because there is no particle trap on the creeping side of the spacer, where the electrical characteristics tend to be low, and the electrical characteristics of the gas space are generally better than those on the creeping surface. There is no electrical problem with shortening the insulation distance.

[Brief explanation of the drawing]

Fig. 1 is a sectional view perpendicular to the length direction of a conduit aerial cable as an embodiment of the present invention, and Fig. 2 is a sectional view in the same length direction, where 1 is a sheath, 2 is a columnar 3 is a conductor, 5 is a particle trapping electrode, 4 is a hole drilled on the electrode, 6 is a support for the electrode, and 7 is a trap.

Claims (1)

[Scope of utility model registration request] A columnar insulating spacer is fixed to the inner surface of the sheath or the casing to support the conductor at a position directly above the conductor, and a columnar insulating spacer corresponding to the conductor is fixed at a position on the opposite side beyond the columnar insulating spacer and the conductor. A particle trap for gas insulated equipment, which is equipped with a particle trap.