JPS587787Y2 - Bus duct line mainly used for large capacity - Google Patents

Description

[Detailed description of the invention] This invention is an improvement of a bus duct line constructed using a so-called insulated bus duct, in which the bus bars of each phase are placed in close contact with each other via their insulation coatings and housed in a duct housing. Regarding.

The insulated bus duct is more compact and has an impedance of 7>D compared to the so-called fully stunned F-type bus duct, in which the bus bars of each phase are housed in a duct housing with intervals between them.
The J-shaped structure also had the feature of high short-circuit strength, and was widely used in practical use. Basically, it had the following structure.

That is, to explain with reference to FIG. 1, a pair of duct joint plates 1 as
A duct housing D provided with b, and a bus bar BR of each phase that are housed in parallel in close contact with each other in this duct housing D with an insulating coating interposed therebetween.

If BS and BT are to be connected to each other, the respective duct joint plates 1a and 1b are connected in an overlapping manner, and between the sides of the duct joint plates 1a and 1b, the bus lines BR and BS of each phase are connected. , while the longitudinal ends of the BTs are expanded and protruded so as to be spaced apart from each other, the respective busbars are overlapped with each other,
Then, an insulating spacer 3 is interposed between the different phases of this overlapping part and between the duct joint plate Iaslb, and a bolt 4 is passed through between the duct joint plates 1a and lb, and a nut 5
By tightening with , a configuration in which the overlapping portions of each phase are collectively connected by pressure can be achieved.

By the way, this type of bus duct is usually 2500A or less, and is constructed with one conductor per conductor in parallel on the left and right. Therefore, unless the current capacity is made larger than this, the height in the duct cross section will increase. The length is only about 30 cm, and the characteristics of an insulated bus duct can be fully demonstrated.

However, if the current capacity is higher than that, two or three conductors are used per phase - and one parallel conductor for each phase is arranged in a two- or three-story structure above and below. Usually, the duct is constructed in such a way that the height of the cross section of the duct can be as large as about 800 m, which cannot be said to be compact anymore.

Moreover, since the two or three conductors that make up one phase are each independent and connected separately and in an insulated state, there is a tendency for a potential difference to occur between conductors of the same phase, and it is necessary to correct the potential difference. As a voltage equalizer, it is required to install a special conductor in the duct that shorts the conductors of the same phase.
This necessitated an increase in connection man-hours and parts, which was uneconomical.

On the other hand, in order to solve these problems, large-capacity bus ducts of 3,000 A or more can be constructed using conductors of large thickness and large cross-sectional area.
Due to the increase in the wall skin coefficient and the decrease in heat dissipation efficiency, which is considered to be a conductor structure, the current conduction efficiency (allowable current per unit cross-sectional area) is significantly reduced, and it cannot be an economical design.

The present invention was developed in view of the existing circumstances, and its purpose is to maintain the compactness of the insulated bus duct, increase current carrying efficiency, and make it suitable for large capacity applications. The point is to provide a bus duct line.

In other words, as shown in Figs. 1 to 3, the line of the present invention employs an insulated bus duct, and in addition to the distribution line, the buses BR, BS, and BT of each phase are insulated on the circumference of a rectangular conductor. It is constituted by a group bus bar in which a plurality of insulated conductors 2a * 2b - 2c formed by applying the above are brought into close contact with each other via the insulation coating, and the respective insulated conductors 2a and 2a and 2b and 2b in this group bus bar are and 2c and 2
c 7%.

The conductor terminals of the insulated conductors from which the insulation coating has been removed are directly overlapped at the overlapping part set between the insulating spacers 3 for each phase, and the duct joint plate 1a*1
The reason is that the bolts 4 and nuts 5 passing through the space B are brought into contact with each other by the tightening force, thereby making the parts conductive.

The figure shows an example of a three-wire insulated bus duct in which one phase is composed of two insulated conductors.

Insulated conductor 2a 2a is R phase, same <'2b-2b is S
t[&2cm2c constitute the T phase.

The duct housing D is assembled by a [shape steel plate duct) l) 1 m DI that tightens and holds these six insulated conductors, and a duct) D2 @D2 that closes the upper and lower sides of this duct.

6 is a bolt for tightening and assembling the ducts Dl and Dl together.

7 indicates a Belleville washer.

Referring to the above example, if the thickness of one conductor is t,
The thickness of the conductor per unit is equivalent to 2t, but since each conductor is in close contact with each other through an insulating coating, the skin coefficient is equivalent to 2t of conductor 1
It can be made much smaller than in the case of one sheet.

According to the present invention as described above, the skin effect can be sufficiently reduced compared to a single conductor within the thickness, and it is also possible to reduce the skin effect, which is common in configurations in which the bus bar per unit is made of two or more double conductors. This can be achieved by direct connections between the conductors themselves, without the need for special short-circuiting members, and without increasing the installation space and preventing drift in the respective in-phase conductors. Therefore, it is possible to install a bus duct line with a space factor close to that of an insulated bus duct that uses one conductor per conductor, and has the practical benefit of being able to economically provide a bus duct line that is more compact and suitable for large capacity applications. play.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway plan explanatory diagram showing an embodiment of the bus duct line of the present invention, and FIG. 3 is the same as that shown in FIG.
It is a Y-line cross-sectional explanatory diagram. D=Duct housing, BR, BS BT: Phase bus, 2
a, 2b, 2c: insulated conductor, 3: insulated spacer, 4:
Boruto, 5: Natsuto.

Claims (1)

[Scope of utility model registration request] A duct housing with a pair of duct joint plates facing each other on the sides between the respective ends, busbars of each phase housed in parallel in close contact with each of the duct housings via an insulating coating, and this duct housing. The overlapping part of each phase is formed by expanding and projecting the longitudinal end of the generatrix of each phase so as to be separated from each other between the side surfaces of the duct joint plate, and the overlapping part is interposed between different phases of this overlapping part and between the duct joint plates. Insulating spacer placed,
In a bus duct line equipped with a fastening member that penetrates between each duct joint plate and presses the overlapping portion of each phase via an insulating spacer, the bus bar of each phase has an insulating coating on the circumference of a rectangular conductor. The assembled bus bar is made up of a plurality of strips of insulated conductors formed by applying the same method and is brought into close contact with each other via the insulating coating, and each insulated conductor in this assembled bus bar is formed into a conductor terminal with the insulation coating of the insulated conductor removed. A bus duct line mainly used for large-capacity applications, characterized in that the comrades are directly overlapped at the overlapping part of each phase and are brought into contact with each other by pressing a fastening member to make them have an equal potential.