JPS626816Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a gas-insulated bus bar incorporating three-phase conductors.

[Technical background and problems of the invention]

In recent years, in substations and switchyards in and around large cities, equipment such as circuit breakers, transformers, current transformers, and disconnectors are housed in insulating gas tanks, and they are insulated with gas. By connecting them with busbars and arranging them three-dimensionally, we aim to reduce the land area.

The gas insulated bus bar that connects each device in this way is constructed as shown in FIGS. 1 and 2. That is, 1 is a cylindrical case, and bus conductors 3a, 3b, 3c for three phases arranged triangularly are inserted in the axial direction into an insulating gas (SF ₆ etc.) in this case 1, and these conductors 3a, 3b , 3c are supported by insulating spacers 2 provided at the case connection portions. 4a, 4b
are pipe-shaped branch conductors branched from bus conductors 3a and 3b, and these branch conductors 4a and 4b are case 1.
Branch cases 6 connected to the tube seats 5a and 5b, respectively.
a and 6b lead to a predetermined device. Insulating spacers 7 support the branch conductors 4a and 4b, respectively.

By the way, when a branch conductor is provided for the three-phase bus conductors 3a, 3b, and 3c arranged triangularly in the case 1 as described above, the branch conductor 4b branching from the one-phase conductor 3b is inevitably the bus conductor of another phase. 3
It will be pulled out through the space between a and 3c. Therefore, this conductor 4b and the bus conductors 3a, 3 that intersect with this conductor 4b
The insulating interval between C and C is shorter than other parts, and this part becomes a weak point in terms of insulation. Furthermore, in order to ensure a sufficient insulation interval in this part, the case itself must be made larger, and the diameter of the insulation spacer must also be increased, which increases manufacturing costs and makes the case expensive.

[Purpose of invention]

The present invention has been devised in view of the above points, and an object of the present invention is to provide an economical gas-insulated busbar that can ensure sufficient insulation at busbar branch portions without increasing the size of the busbar case.

[Summary of the idea]

The present invention includes a cylindrical case, bus conductors for three phases arranged triangularly inside the case and inserted in the axial direction, and a bus conductor branching from one phase conductor of the bus conductors and connecting the bus conductors of the other two phases. In a gas-insulated busbar having a pipe-like branch conductor led out through the
The intersecting portion of the branch conductor with the bus conductor of the other phase is formed to have a diameter smaller than that of this conductor, and the conductor is provided with a ventilation hole for circulating the gas in the case inside the conductor by convection. shall be.

[Example of idea]

FIGS. 3 and 4 show an embodiment of the present invention, and the gas insulated busbar shown in the figure is a three-phase busbar conductor 3a arranged triangularly in a cylindrical case 1 and inserted in the axial direction.
A pipe-shaped branch conductor 4b that branches from the bus conductor 3b of one phase among the conductors 3b and 3c of the other phase and is led to the branch case 6b between the conductors 3a and 3c of the other phase, the intersection portion 4b with the other phase conductors 3a and 3c is connected to this conductor. The conductor 4b is formed to have a smaller diameter than the conductor diameter D of the conductor 4b.
Vent holes 8a and 8b opening into the case 1 are provided at the bottom and top of the case 1, respectively.
The insulating gas inside the case is circulated through the conductor 4b by convection as shown by the arrow. In the drawings, the same parts and corresponding parts as those shown in FIGS. 1 and 2 are given the same reference numerals.

With this configuration, it is possible to provide a sufficient insulation distance between the branch conductor 4b and the other phase conductors 3a and 3b that intersect with it without increasing the size of the case 1, thereby increasing the withstand voltage of the entire device. It can be stabilized.
Further, since the small diameter portion of the branch conductor 4b is cooled by the insulating gas flowing from the inside and outside by natural convection, the temperature rise due to the increase in resistance is effectively reduced, and a sufficient current carrying capacity can be provided.

In the embodiment shown in FIG. 5, a plurality of cooling fins 9 are spirally provided on the inner peripheral surface of the branch conductor 4b, and the cooling effect of the branch conductor can be further enhanced. Further, as shown in FIG. 5, cooling fins 10 may be provided on the outer circumferential surface of the tube seat 5b provided in the case 1. In this way, the heat dissipation of the case 1 is improved and the cooling effect of the branch conductor is enhanced. In addition, it has the effect of improving the strength against the load of the equipment attached to the tube seat 5b.

[Effect of idea]

According to the present invention, it is possible to secure the interphase insulation distance at the branch part of the bus conductor to a desired value without increasing the size of the case containing the bus conductor.
An economical gas-insulated bus bar with stable voltage resistance can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional gas insulated bus bar, FIG. 2 is a sectional view taken along the line in FIG.
The figures are Fig. 3 - a sectional view taken along the line, Fig. 5 is a sectional view showing another embodiment of the present invention, and Fig. 6 is Fig. 5 -
FIG. 1...Case, 3a-3c...Conductor, 4a, 4
b...Branch conductor, 8a, 8b...Vent hole.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) Bus conductors for three phases arranged triangularly in a cylindrical case filled with insulating gas and inserted in the axial direction of the case, and one phase of these bus conductors. A pipe-shaped branch conductor is branched from the bus conductor of the bus conductor and is drawn out through between the bus conductors of the other two phases, and the intersection portion of the branch conductor with the bus conductor of the other phase is larger than the conductor diameter of the bus conductor. 1. A gas insulated bus bar, characterized in that the bus conductor is formed to have a small diameter and is provided with a ventilation hole for circulating the gas in the case through the bus conductor by convection. (2) The gas insulated bus bar according to claim 1 of the utility model registration, wherein cooling fins are provided on the inner circumferential surface of the branch conductor.