JPH0582364A - Reactor - Google Patents

Abstract

PURPOSE:To reduce a fringing magnetic flux by means of an electromagnetic induction action and to prevent an eddy-current loss caused in a coil by a constitution wherein a compensation coil is installed in a gap part in an iron-core leg. CONSTITUTION:A compensation coil 5 does not form one turn against a magnetic flux phi1 which is passed in an iron-core leg 2 while it is being passed in a gap 3. As a result, no trouble is caused in an action as a reactor. On the other hand, a fringing magnetic flux phi2 is interlinked with the compensation coil 5 in a gap A, and an electric current which offsets the fringing magnetic flux phi2 by means of an electromagnetic induction action flows in the compensation coil 5. As a result, it is possible to avoid that a local loss is caused in a coil 4 and that the coil is overheated by the loss. When the compensation coil is connected to an external coil, electric power can be utilized and the overall efficiency of the title reactor is enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reactor having a void in an iron core leg.

[0002]

2. Description of the Related Art FIG. 8 is a cross-sectional view showing a conventional reactor described on pages 305 to 306 of "Transformer design work method" issued by Densho Shoin in 1960, where 1 is a silicon steel strip. 2 is an iron core of the iron core 1,
3 is a void provided in the iron core leg 2 and 4 is a coil wound around the iron core leg 2. As shown in the perspective view of FIG. 10, the cross section is rectangular and an insulator (not shown) is formed on the surface thereof. It is wound in a cylindrical shape by using a single conductor or a double conductor composed of the element wire 41 insulated.

In such a reactor, as shown in FIG. 9, most of the magnetic flux φ ₁ passes through the core leg 2 and the gap 3
While passing through, a part of it becomes fringing magnetic flux φ ₂ at the location of the air gap 3 and spreads outward from the core leg 2. When using the coil 4 as shown in FIG. 10 in this context, fringing flux phi ₂ passes through the middle strands 41 of the coil 4 as shown in FIG. 11, the direction of the fringing flux phi ₂ Since the dimension of the wire 41 in the perpendicular direction is large, the eddy current loss generated in the coil 4 is large. In the case of the coil 4 in which the width dimension D and the thickness dimension t (D> t) of the wire 5 are reversed and edgewise winding is performed as shown in FIG. 12, the same behavior as described above is exhibited.

[0004]

Since the conventional reactor is constructed as described above, a large eddy current loss occurs in the coil due to the fringing magnetic flux, which causes the temperature to rise and the insulation used in the coil. There are problems that the life of the product is shortened and that the efficiency is reduced due to the power loss. The present invention has been made to solve the above problems, and an object thereof is to obtain an efficient reactor having a long life of an insulator used for a coil.

[0005]

SUMMARY OF THE INVENTION In a reactor according to the present invention, a conductor having approximately one turn and open at both ends is formed at a gap between a coil and an iron core leg at right angles to the axis of the iron core leg. Two conductors are arranged apart from each other in the direction, and corresponding ends of the two conductors are connected to each other.
Further, instead of connecting both ends of the two conductors to each other in the above description, one end corresponding to each other is connected and the other end is connected to an external circuit.

[0006]

The reactor according to the present invention cancels the magnetic flux passing through the space surrounded by the two conductors by the electromagnetic induction action, so that the fringing magnetic flux is reduced. Further, by connecting one ends of the two conductors and connecting the other ends to an external circuit, it is possible to reduce fringing magnetic flux and use electric power in the external circuit.

[0007]

EXAMPLES Example 1. 1 is a sectional view showing a reactor according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. In these figures, 1 to 4 are the same as in the conventional example of FIG. Reference numeral 5 is a compensating coil, 6 is a first conductor arranged in a space 3 between the coil 4 and the iron core leg 2, and forms about 1 turn,
Both ends thereof, that is, the winding start and the winding end are open without closing each other. 7 is a second conductor similar to the first conductor 6,
The first conductor 6 is arranged outside the first conductor 6 at a distance of A from the axis of the iron core leg 2 at a right angle. 8, 9 correspond to each other at both ends of the first and second conductors 6, 7, that is,
First and second connecting the beginning of winding and the end of winding
Is the connection part of. 6 to 9 are integrated to form the compensation coil 5
To form a closed circuit. FIG. 3 shows a perspective view thereof.

Next, the operation will be described. With respect to the magnetic flux φ ₁ passing through the iron core leg 2 while passing through the air gap 3, the compensation coil 5 does not form one turn, so that there is no hindrance to the operation as a reactor. On the other hand, the fringing magnetic flux φ ₂ interlinks with the compensating coil 5 at the interval A, and a current that cancels the fringing magnetic flux φ ₂ flows in the compensating coil 5 by the electromagnetic induction effect. For this reason, it is possible to avoid local loss occurrence in the coil 4 and the like and overheating due to this.

Embodiment 2. FIG. 4 is a sectional view showing a reactor according to another embodiment of the present invention.
5 is a perspective view of FIG. The dimension of the second conductor 7 in the height direction in the drawing is made larger than that of the first conductor 6. Therefore, the compensation coil 5 shown by the alternate long and short dash line in FIG.
The area and the direction of the opening of are more suitable for interlinking with the fringing magnetic flux φ ₂ .

Embodiment 3. FIG. 7 is an explanatory view showing a compensating coil of a reactor according to still another embodiment of the present invention,
Corresponding one ends of the first and second conductors 6 and 7 are connected to each other at the connection portion 8, but the other ends are not connected to each other, and terminals 10 are provided respectively to the external circuit.
Connected to 11. The external circuit 11 is, for example, a rectifier circuit 12
And a smoothing circuit 13. In this embodiment, the fringing magnetic flux is reduced by the current flowing through the compensation coil 5, and the efficiency can be improved by utilizing the electric power through the external circuit 11.

In the above embodiment, the reactor having the void 3 at one location is shown, but the same applies to a reactor having two or more locations at the void 3.

[0012]

As described above, according to the present invention, the compensating coil is provided in the void portion of the iron core leg.
The fringing magnetic flux is reduced by the electromagnetic induction action, and thus a large eddy current loss generated in the coil is prevented, so that the life of the insulator is extended and the efficiency is improved. Further, by connecting the compensation coil to the external coil, electric power can be used, and in addition to the above effects, there is an effect that the overall efficiency is improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a reactor according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

3 is a perspective view showing a compensation coil of the reactor of FIG. 1. FIG.

FIG. 4 is a sectional view showing a reactor according to a second embodiment of the present invention.

5 is a perspective view showing a compensation coil of the reactor of FIG. 4. FIG.

FIG. 6 is an explanatory diagram showing the operation of the compensation coil of FIG.

FIG. 7 is an explanatory diagram showing a compensating coil of a reactor according to a third embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a conventional reactor.

9 is an explanatory diagram showing the operation of the reactor of FIG. 8. FIG.

10 is a cross-sectional view showing a coil of the reactor of FIG.

FIG. 11 is an explanatory view showing the operation of the reactor of FIG.

FIG. 12 is an explanatory diagram showing the operation of another conventional reactor.

[Explanation of symbols]

 2 core leg 3 air gap 4 coil 6 first conductor 7 second conductor 8 first connecting portion 9 second connecting portion 10 terminal 11 external circuit

Claims (2)

[Claims] 1. A reactor comprising a core leg having a void and a coil wound around the core leg, wherein the void is located between the coil and the core leg.
Two conductors that form a turn and are open at both ends are arranged apart from each other in a direction perpendicular to the axis of the iron core leg, and the corresponding ends of the two conductors are connected to each other. Reactor to do. 2. The reactor according to claim 1, wherein 2
A reactor characterized in that, instead of connecting mutually corresponding ends of one conductor, two corresponding ends of two conductors are connected and the other end is connected to an external circuit.