JPS5915365B2 - air core reactor - Google Patents

Description

[Detailed Description of the Invention] This invention mainly consists of a power conversion device using large semiconductors,
For example, the present invention relates to an air core reactor used in a chopper device, a commutation circuit for semiconductor devices in an inverter device, a semiconductor device protection circuit, and the like.

Conventionally, this type of air-core reactor is as shown in Figure 1.
It has a structure in which an electric wire 2 is spirally wound around the outer periphery of a cylindrical winding frame 1 in the axial direction. Therefore, in this conventional structure, a loop of magnetic flux is formed along the axial direction as shown by the dotted line in FIG. 2, and the peripheral magnetic flux density becomes relatively large. Such leakage magnetic flux causes induction disturbances and signal malfunctions, and has a particularly large effect on semiconductor application devices. For this reason, in the past, a shielding plate made of a copper plate with high magnetic resistance was installed around the air-core reactor.
The drawback was that the device was complicated and heavy. The present invention eliminates the above-mentioned drawbacks, and aims to provide an air-core reactor that reduces the generation of leakage magnetic flux to prevent the influence on peripheral equipment, and also reduces the weight of the entire device. There is a particular thing.

An embodiment of the present invention will be described below with reference to FIGS. 3 to 6. First, Figures 3 and 4 show the assembled state of the air core reactor, in which two winding frames 03a each having a short axis and a cylindrical shape are shown.
, 3b, respectively, to form coils 5a and 5b by winding electric wires 4a and 4b in a toroidal shape, and both coils 5
A, 5b are arranged axially adjacent to each other with an insulating plate 6 interposed between them, and a plurality of insulating studs 8 are installed between the coil supporting metal fittings Tl□ on both sides.
...However, it has a built-in retainer 15, and both coils 5a,
5b are connected to each other so that the current directions are opposite to each other.

Here, to explain the winding direction of the electric wires 4a, 4b of the above-mentioned coils 5a, 5b and the mutual energized connection state from FIG. The diagram shows a schematic view of the developed state as seen from a shifted position.As can be seen from this figure, one coil 5a is wound with the wire 4a between the starting end 4a- and the terminal end 4a-2 facing clockwise with respect to the winding frame 3a. On the other hand, the other coil 5b is connected to the winding frame 3b between the starting end 4b and the end of the wire 4b.
The wire is wound in a counterclockwise direction.

The terminal end 4a-2 of the electric wire 4a of the one coil 5a and the starting end 304b- of the electric wire 4b of the other coil 5b are connected so that currents flow in opposite directions. When the air-core reactor having the above-mentioned configuration is energized, as shown in FIG.
At the same time, a clockwise magnetic line of force 9a35 is generated on a concentric circle, and at the same time, a clockwise loop-shaped leakage magnetic line of force 10a, which surrounds each electric wire 4a, is generated on the outside of the winding frame 3a.

In addition, the other coil 5b is connected to the above-mentioned one coil 5a.
Lines of magnetic force 9b and leakage lines of magnetic force 10a, which are completely opposite to each other...
However, since both coils 5a and 5b are combined adjacent to each other in the axial direction as shown in FIG. Almost no lines of magnetic force leak out to the outside, making it possible to prevent induction disturbances and signal malfunctions to peripheral equipment.

FIG. 7 shows another embodiment of the present invention, in which three cylindrical winding frames 3a, 3b, 3c are provided with electric wires 4a, 4b,
4c is wound in a toroidal shape to form coils 5a, 5b, 5c.
These coils 5a, 5b, and 5c which are adjacent to each other in the axial direction and are connected in the same manner as in FIG. 4 are combined and joined so that the directions of current conduction are opposite to each other. In such an odd number combination structure, leakage magnetic flux for one coil is always generated, but the amount of leakage in this case is very small (negligible).

Although the above-mentioned embodiments have been shown to have a structure in which two or three coils are combined, the present invention is not limited to this, and may also be a structure in which four or more coils are combined. In the above embodiment, the winding direction of the wire with respect to the winding frame of each coil is reversed, but the present invention is not limited to this, and the winding direction of the wire is the same for each coil and the mutual connection is made in the above embodiment. A similar effect can be obtained even if the configuration is reversed.

The present invention, as described in detail above, reduces the generation of magnetic lines of force leaking to the outside, prevents induction disturbances and signal malfunctions to peripheral equipment, especially semiconductor application equipment, and prevents magnetic shielding from conventional magnetic shielding. Since no plate is required, the device has remarkable effects such as being able to simplify and reduce the weight of the device.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a conventional air-core reactor, FIG. 2 is a principle diagram of a conventional air-core reactor, FIG. 3 is a front view showing an embodiment of the present invention, and FIG. 4 is a side view of the same. Figure 5 is a developed view, Figure 6 is a principle diagram of the air core reactor corresponding to Figure 5,
FIG. 7 is a developed view showing another embodiment of the present invention. 1... Winding frame, 2... Electric wire, 3a, 3b, 3c...
Winding frame, 4a, 4b, 4c...Electric wire, 5a, 5b, 5c
···coil.

Claims (1)

[Claims] 1. It is characterized by being constructed by combining a plurality of coils made by winding electric wire in a toroidal shape around a cylindrical winding frame in the axial direction, and connecting adjacent coils so that the direction of the current is opposite to each other. air core reactor.