JPS5936090Y2 - busbar support device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a busbar support device used in electrical equipment such as closed switchboards and bus ducts.

Hereinafter, a conventional bus bar support device used in electrical equipment such as a closed switchboard or a bus duct, as shown in FIGS. 1 to 4, will be explained.

1 and 2 show a bus bar support device using an integrally molded insulating member, and FIGS. 3 and 4 show a bus bar support device using a support insulator, respectively.

In FIGS. 1 and 2, reference numeral 1 denotes the box body of the board, which is at ground potential.

Reference numeral 2 denotes a plurality of busbars housed in the box 1, and the figure shows a case in which three busbars are provided.

In other words, it forms a three-phase bus.

Reference numeral 3 denotes a first insulating member that is attached to a support fitting 5 (described later) with a bolt (not shown) and supports the bus bar 2 while maintaining the distance therebetween. Fixed.

Reference numeral 4 denotes a second insulating member provided on the first insulating member 3 and disposed between each bus bar 2 and between the bus bar 2 and the inner wall of the box body 1. It is integrally molded with the insulating member 3 of No. 1.

A supporting metal fitting 5 is attached to the inner wall of the box body 1, supports the first insulating member 3, and is at ground potential.

Regarding the conventional bus bar support device configured in this way,
Each bus bar 2 is insulated by a first insulating member 3 and a second insulating member 4 so that the distance therebetween is maintained, and insulation between phases and ground of the bus bar 2 is provided by the first insulating member 3 and the second insulating member 4. The surface creepage distance is maintained at .

Further, in the event of a short-circuit accident between phases, a large electromagnetic repulsive force or attractive force is generated between the bus bars 2.

The support strength that can withstand this large force is provided by the first insulating member 3,
This is achieved by the compressive and tensile strength of the second insulating member 4.

On the other hand, in FIGS. 3 and 4, 1 is a box, 2 is a busbar, and 6 is a support insulator that is attached to a support fitting 7 (described later) with bolts (not shown) and separately supports the busbar 2 while maintaining the interval. The support insulator 6 and the bus bar 2 are tightened and fixed with bolts (not shown).

I is a support metal fitting attached to the bottom plate of the box body 1, supporting the support insulator 6, and being at ground potential.

In the conventional bus bar support device configured in this way,
The distance between the busbars 2 is maintained by the support insulator 6,
Insulation between the phases of the bus bar 2 and between the ground and the ground is maintained by the length and diameter of the support insulator 6.

The bending strength of the support insulator 6 provides support strength capable of withstanding the large force generated between the busbars 2 in the event of a short-circuit accident between the casing and the phases.

However, each of the above-mentioned conventional busbar support devices has had various problems.

In the former case, since the insulation between the phases of the bus bar 2 and the ground is maintained by the surface creepage distance of the first insulating member 3 and the second insulating member 4, the first insulating member 3 and the second insulating member Part 4
When the dielectric strength between the phases and the ground of the bus bar 2 decreases due to deterioration of the bus bar 2, leading to creeping dielectric breakdown, there is a possibility that the dielectric breakdown between the phases will occur before the dielectric breakdown between the phases and the ground.

In other words, among the accidents on bus 2, the phase-to-phase short circuit accident, which should be avoided as much as possible, will occur first, and the fault on bus 2 cannot be detected due to the ground fault between the ground and bus 2. The damage to electrical equipment was extremely large, and there was a drawback of poor electrical reliability.

However, since the compressive and tensile strengths of the first insulating member 3 and the second insulating member 4 provide support strength capable of withstanding the large force generated between the busbars 2 in the event of a short-circuit accident between phases, sufficient support is provided. It has good strength and mechanical reliability.

On the other hand, in the latter case, the support insulator 6 attached to the support fitting 7 at the ground potential provides insulation between the phases and the ground of the bus bar 2.
Since the supporting insulator 6 is held in place by its length and diameter, when the dielectric strength between the phases and ground of the bus bar 2 decreases due to deterioration of the support insulator 6, leading to dielectric breakdown, the support metal 7 which is at ground potential Due to the action of , the dielectric breakdown between the ground and the ground occurs before the dielectric breakdown between the phases.

That is, a fault in the bus bar 2 can be detected from a fault in the ground fault, and damage to electrical equipment due to a fault in the bus bar 2 is minimized, resulting in excellent electrical reliability.

However, since the bending strength of the support insulator 6 has enough support strength to withstand the large force generated between the busbars 2 in the event of a short-circuit accident between phases, there is a risk that the support insulator 6 will be damaged, which may affect mechanical reliability. It had some disadvantages.

In order to improve this mechanical reliability, the supporting insulator 6 must be made larger, which has the disadvantage of being expensive.

This invention was made in view of the above-mentioned drawbacks, and the purpose is to provide a bus bar support device that has excellent electrical reliability and mechanical reliability.

An embodiment of this invention will be described below with reference to FIGS. 5 to 7.

In each of these figures, 1 is a box, 2 is a busbar, and 8 is a first insulating member that is attached to a support member 10 (described later) with bolts (not shown) and supports the busbar 2 while maintaining the interval. The insulating member 8 and bus bar 2 are fastened and fixed by bolts (not shown).

Reference numeral 9 denotes a second insulating member, for example, two insulating members arranged between each bus bar 2 and provided on the first insulating member 8, and the second insulating member 9 and the first insulating member 8 are integrally molded. has been done.

Reference numeral 10 denotes a support member disposed between the second insulating members 9, attached to the bottom plate of the box body 1, supporting the first insulating member 8, and at ground potential, supporting the first insulating member 8. It is composed of a support 10a and an enclosure 10b surrounding the support.

In the bus bar support device of this invention configured as described above, the bus bar 2 is connected to the first insulating member 8 and the second insulating member 9.
Insulation between the phases of the bus bar 2 and the ground is maintained by the surface creepage distance of the first insulating member 8 and the second insulating member 9.

The compressive and tensile strengths of the first insulating member 8 and the second insulating member 9 provide support strength capable of withstanding the force generated between the busbars 2 in the event of a short-circuit accident between the phases.

The first insulating member 8 is supported by a support member 10 placed between the second insulating members 9 and at ground potential.

However, even if the dielectric strength between the phases and ground of the bus bar 2 decreases due to deterioration of the first insulating member 8 and the second insulating member 9, resulting in creepage breakdown, the Due to the action of the support member 10 at ground potential, a ground-to-ground fault occurs prior to a short-circuit fault between phases.

Therefore, a fault in the bus bar 2 can be detected in a ground fault fault between the bus bar 2 and the ground, and damage to electrical equipment due to a fault in the bus bar 2 is minimized, resulting in excellent electrical reliability.

In addition, since the compressive and tensile strengths of the first insulating member 8 and the second insulating member 9 provide support strength capable of withstanding the large force generated between the busbars 2 in the event of a short-circuit accident between phases, the supporting insulator structure It is less bulky and cheaper than , and has sufficient support strength and excellent mechanical reliability.

As mentioned above, the drawbacks of the conventional busbar support devices shown in FIGS. 1 and 2 that cause a short circuit accident between phases, and the mechanical reliability of the conventional busbar support devices shown in FIGS. 3 and 4 are explained. It is possible to obtain a highly reliable bus bar support device that simultaneously eliminates the disadvantages of increasing the size of the support insulator 6 and high cost.

In the above embodiment, two second insulating members 9 are arranged between each bus bar 2 and provided on the first insulating member 8, and a support member 10 at ground potential is arranged between the second insulating members 9. As described above, if three or more second insulating members 9 are arranged between each bus bar 2 and provided on the first insulating member 8, a ground fault between the phases and the ground can be prevented before a short circuit between phases. A support member 10 may be arranged between the second insulating members 9 so that this occurs.

Further, in the above embodiment, the case where the support member 10 is composed of the support body 10a and the enclosure body 10b, that is, the case where it surrounds the support part of the first insulating member 8, has been described, but there are some effects. However, the enclosure 10b is omitted and the support 1
The support member 10 may be configured only with Oa.

In the above embodiment, when three busbars 2 are provided, that is,
Although I mentioned the three-phase bus, this bus 2 has at least two phases.
It is only necessary to have each one individually, and the same effects as in the above embodiment can be achieved.

By the way, in the above explanation, the invention was applied to a busbar support device used in closed switchboards and bus duct electrical equipment, but it can also be applied to busbar support devices used in other electrical equipment. Of course.

As explained above, in this invention, a plurality of busbars are supported by a first insulating member, a plurality of second insulating members arranged between each busbar are provided on this first insulating member, and this second insulating member is provided with a plurality of second insulating members arranged between each busbar. Since the support member at ground potential is provided between the insulating members to support the first insulating member, it is possible to obtain a bus bar support device with excellent electrical reliability and mechanical reliability.

[Brief explanation of the drawing]

FIG. 1 is a sectional front view showing a conventional bus bar support device, FIG. 2 is a sectional view taken along the H-line in FIG. 1, and FIG. 3 is a sectional front view showing another type of conventional bus bar support device. 4 is a sectional view taken along the rV-rV line in FIG. 3, FIG. 5 is a sectional front view showing a bus bar support device according to an embodiment of this invention, and
The figure is a sectional view taken along the line VI--VI in FIG. 5, and FIG. 7 is a sectional view taken along the line ■--■ in FIG. In the figure, 2 is a bus bar, 8 is a first insulating member, and 9 is a second insulating member.
10 is an insulating member, and 10 is a support member. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (υ A first insulating member supporting a plurality of bus bars, and a plurality of second insulating members installed between each of the bus bars and provided on the first insulating member. , and a support member disposed between the second insulating members to support the first insulating member and being at ground potential. (2) The first insulating member and the second insulating member. The bus bar support device according to claim 1 of the utility model registration claim, characterized in that the bus bar support device is configured integrally with the bus bar. (3) The bus bar support device is characterized in that two second insulating members are disposed between each bus bar. Scope of claims for utility model registration, paragraph 1 or 2
Busbar support device as described in Section 1. (4) The busbar support device according to any one of claims 1 to 3, wherein the support member surrounds and supports the support portion of the first insulating member.