JPS589468Y2 - phase separation busbar - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a phase-separated bus bar with a continuous grounding structure used for power supply and demand, and relates to a structure for preventing local heating caused by induced current.

As is already well known, as shown in FIG. 1, the phase-separated busbar of a continuous ground plane uses a cylindrical sheathing member made of a good conductor such as aluminum or its alloy, and both ends of this sheathing member 1 are A short circuit plate 3 is welded to the button cover member 1 to form a closed circuit between the button cover members 1.

When three phases are installed in parallel and additional power is applied, it is possible to prevent induction heating of adjacent cross members due to the induced current 5 flowing in the jacket 1 in almost the same direction opposite to the conductor current 4, and to reduce electromagnetic force in the event of a short circuit. It is decreasing.

Normally, a phase-separated bus bar is used when carrying a large current of several thousand to tens of thousands of A, and when three phases are arranged in parallel and energized as described above, the induced current 5 of each phase flowing through the jacket member 1 is , flows between each phase via the shorting plate 3 as shown in the figure.

The short-circuiting plate 3 is the first
As shown in the figure, drilling holes 3 in the part facing the end surface.
However, for this reason, the cross-sectional areas of portions A and B shown in the figure become extremely small.

As the circuit current becomes larger, a larger induced current flows through the shorting plate 3, so that the current density in the above-mentioned portions A and B increases, causing local heating.

Therefore, as a countermeasure against this local heating, it is sufficient to increase the cross-sectional area of portions A and B of the shorting plate 3 to reduce the current density.

As a method for this purpose, methods such as increasing the thickness of the shorting plate 3 or increasing the external dimensions have been considered.

However, when the thickness of the plate is increased, the manufacturing process such as drilling holes in the shorting plate 3 becomes difficult, and when the external dimensions are increased, installation on site becomes difficult, which causes an increase in price. Ta.

An object of the present invention is to provide a phase separation bus bar in which local heating can be easily prevented by improving the shape of the shorting plate.

The present invention will be described below with reference to an embodiment shown in the drawings.

In FIG. 2, reference numeral 6 denotes a short-circuiting plate, on which the induced current flowing through the jacket member 1 of each phase concentrates as described above.

For this reason, by making a circular hole 6a in the part of the shorting plate 6 that faces the openings at both ends of the sheathed conductor 1, the cross-sectional area of parts A and B can be increased while maintaining the external dimensions of the shorting plate 6. There is.

Here, the radius of the sheathing member 1 is usually determined by the insulation distance determined by the rated voltage of the conductor 2 in order to suppress the temperature rise of the conductor 2 within a specified value (Here, the radius of the conductor 2 is determined for ease of comparison with the radius described above). (referring to the distance in the radial direction from the center).

For this reason, the radius C of the hole 6a in the direction substantially perpendicular to the interphase direction of each jacket member 1 is formed into a circular shape as described above, and the cross-sectional area of the A part and B part is increased within a certain range. Also, sufficient insulation distance can be ensured.

In this case, part of the A part and B part of the short circuit plate 6 is
Although the end face opening of the conductor 1 is partially covered, the ventilation resistance increases slightly, and the ventilation cooling function for the conductor 1 is also slightly reduced, but this can be sufficiently covered by other means, such as slightly increasing the ventilation capacity. It is a matter of degree.

In this way, it is possible to prevent local heating of the neutralized portion of the short circuit plate by simply changing the shape of the hole 6a provided in the short circuit plate 6 currently in use without changing the thickness, external dimensions, etc. of the short circuit plate 6.

For this reason, as a result of conducting a current conduction test with a current of 30 KA with three phases installed in parallel, it was found that in the case of the conventional short circuit plate, the temperature rise value of the short circuit plate 6 facing the external member of the middle phase was 70 ° C or more. In the case of the short-circuit plate of the present invention, the temperature rise is 40℃ in the middle phase as well.
It became the following.

It should be noted that the present invention is not limited to the above-mentioned embodiment, and as shown in FIG. Since the cooling air passes through the small holes 7, an even greater cooling effect can be obtained and a larger capacity can be achieved with the same dimensions.

In addition, in the case of a self-cooled phase-separated busbar, there is no need to consider ventilation so much, so if the insulation distance can be secured, instead of drilling a circular hole in the shorting plate 6, a circular hole as shown in Figure 4 can be used. hole 8
You can open it.

Note that FIGS. 3 and 4 show the relationship between the hole 6a or 8 made in the shorting plate 6 and the outer cover 1, and illustration of other members is omitted.

As described above, the cross-sectional area of the induced current flowing part can be increased simply by changing the processing of the holes in the shorting plate according to the present invention, and local heating of the shorting plate due to the induced current can be sufficiently prevented. be.

[Brief explanation of the drawing]

1a and 1) are a plan view and a side view showing a conventional general phase separation bus bar, FIG. 2 is an end face outline view showing an embodiment of the phase separation bus bar according to the present invention, and FIGS. The figure is an end view showing another embodiment of the present invention. 1...Outer cover member, 2...Conductor, 6 doors.
...Short circuit board, 6a, 8...hole, C...
...A radius that is almost perpendicular to the interphase direction.

Claims (1)

[Scope of utility model registration request] Three-phase sheathing members formed into a cylindrical shape made of a highly conductive material are installed approximately in parallel, and a conductor is provided along the axial direction approximately at the center of each of these sheathing members. In cases where both ends of a member are connected by a conductive short-circuiting plate with each end face open, the interphase direction of each outer sheath member of the hole facing the end face opening of the outer sheath member of the short-circuit plate. The length from the center of the conductor to the inner periphery of the hole in the direction orthogonal to the conductor is smaller than the radius of the outer sheath member, which is set longer than the insulation distance corresponding to the rated voltage of the conductor, and is dimensioned to ensure the above insulation distance. A phase separation bus bar characterized in that a short circuit plate corresponding to this portion covers a part of an end face opening of an outer covering member.