JP7066417B2 - Zero-phase current suppression reactor, winding - Google Patents

Description

Embodiments of the present invention relate to a zero-phase current suppression reactor and winding that suppress a zero-phase current.

In recent years, so-called power electronics devices have been adopted in various fields in electric power systems, and various problems have emerged along with them. For example, in a power electronics device such as an inverter, a harmonic current may flow out due to its operation, and the zero-phase current contained in each harmonic component, that is, the components having the same magnitude and the same phase among the three phases When the current flows out to the electric circuit, they do not cancel each other out, so that there is a risk of inducing inductive interference or radio interference around the electric circuit. Therefore, in order to suppress the zero-phase current flowing out of the power electronics device, a zero-phase current suppression reactor may be adopted (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2011-103455

Such a zero-phase current suppression reactor has a configuration in which three winding conductors connected to each of the three-phase electric circuits are wound and magnetically tightly coupled between the winding conductors. While it is necessary to have an inhibitory effect that makes it difficult for the zero-phase current to flow in the electric circuit, it is desirable that it does not interfere with the current of components other than the zero-phase current.

However, if the magnetic coupling of the winding conductors of each phase is uneven, there is a problem that the effect of suppressing the zero-phase current in the electric circuit is reduced, and in addition, the current of components other than the zero-phase current is hindered. It may become.

Therefore, we provide a zero-phase current suppression reactor and winding that can improve the effect of suppressing the zero-phase current and reduce the possibility of hindering the current of components other than the zero-phase current.

In the zero-phase current suppression reactor of the embodiment, three winding conductors connected to a three-phase electric circuit are wound side by side in the axial direction, and each winding conductor has a winding start end and a winding end end. And are in the same position in the circumferential direction, and the winding start end is in a position where the circumferential direction is evenly arranged, so that the lengths of the parts parallel to other winding conductors are equal. It is being wound.

The figure which shows the structure and winding mode of a zero-phase current suppression reactor schematically. The figure which shows the winding mode of a winding conductor schematically. The figure which shows the winding mode of a winding conductor schematically together with an iron core. Diagram to explain the electrical characteristics of the zero-phase current suppression reactor

Hereinafter, embodiments will be described with reference to the drawings.

FIG. 1 shows the configuration and winding mode of the zero-phase current suppression reactor 1 according to the present embodiment, and schematically shows a state in which the zero-phase current suppression reactor 1 formed in a cylindrical shape is expanded in the circumferential direction. Shows. In the case of FIG. 1, the right end side shows the position of 0 degrees in the circumferential direction, and the left end side shows the position of 360 degrees, that is, the position of 0 degrees in one round. In FIG. 1, for the sake of explanation, different hatching is attached to each winding conductor 2 for easy distinction.

The zero-phase current suppression reactor 1 is configured by winding three winding conductors 2 corresponding to three phases of U-phase, V-phase, and W-phase in a state of being arranged in parallel. In each winding conductor 2, for example, a conductor formed by bundling a plurality of litz wires into a flat shape or a conductor using one or a plurality of flat conductors are arranged in parallel so as to be adjacent to each other in the longitudinal direction in the cross-sectional view. It is wound together in a state where it is placed in. Further, the winding conductor 2 is insulated by wrapping an insulating tape or the like around the surface of the winding conductor 2.

Hereinafter, when the winding conductor 2 corresponding to each phase is described, it will be described by adding “u”, “v” or “w” to the reference numerals. Further, hereinafter, the direction in which the winding conductors 2 are adjacent to each other is referred to as an axial direction.

In the case of the zero-phase current suppression reactor 1, the winding conductor 2w of the W phase starts winding (0T) at the 0 degree position in the circumferential direction, and after being wound multiple times, ends winding at the 360 degree position (7T). ). That is, in the case of the W-phase winding conductor 2w, the 0 degree position is the winding start end, and the 360 degree position is the winding end end.

Further, the V-phase winding conductor 2v is wound so that the position of 120 degrees in the circumferential direction is the winding start end, and after being wound a plurality of times, the position of 120 degrees is the winding end end. The U-phase winding conductor 2u is wound so that the position of 240 degrees in the circumferential direction is the winding start end, and after being wound a plurality of times, the position of 240 degrees is the winding end end. In FIG. 1, the winding start end of the U-phase winding conductor 2u is "U", the winding end end is "Ou", the winding start end of the V-phase winding conductor 2u is "V", and the winding end end is "Ov". , The winding start end of the W phase winding conductor 2u is shown as "W", and the winding end end is shown as "Ow".

That is, each winding conductor 2 is wound so that the winding start end and the winding end end are at the same position in the circumferential direction, and the winding start end is arranged at three equal positions in the circumferential direction, that is, in the circumferential direction. It is wound so that it is displaced by 120 degrees. In FIG. 1, the winding start end of the W phase winding conductor 2w is shown as a 0 degree position for convenience, but the winding start position of the U phase winding conductor 2u or the winding start of the V phase winding conductor 2v. Any position can be set to 0 degrees, such as setting the position to 0 degrees. Further, the number of turns of each winding conductor 2 is an example, and the number of turns is not limited to this.

As shown in FIG. 2, the zero-phase current suppression reactor 1 having such a configuration is wound around the outer circumference of the leg portion 3a of the bipod core 3. At this time, in the zero-phase current suppression reactor 1, the winding start end of any of the winding conductors 2 is located on the virtual line (CL) passing through the center of the leg portion 3a and outside the leg portion 3a. Have been placed. In the case of FIG. 2, the zero-phase current suppression reactor 1 is wound so that the winding start end of the U-phase winding conductor 2u is located on the virtual line (CL). In this case, the bipod core 3 formed in an annular shape may be provided with a discontinuous portion such as a so-called gap.

Further, when the winding conductor 2 is wound around the two leg portions 3a of the bipod core 3 as shown in FIG. 3, for example, the winding start end of the U-phase winding conductor 2u is the leg portion 3a. It may be configured to be arranged so as to be located on the virtual line (CL) passing through the center and outside the leg portion 3a. At this time, the winding conductor 2 of each leg portion 3a may be electrically connected in series or in parallel. Instead of the U-phase winding conductor 2, the V-phase winding conductor 2v or the W-phase winding conductor 2w may be wound so as to be located on the virtual line (CL).

Next, the operation of the above configuration will be described.

As described above, the zero-phase current suppression reactor 1 needs to have a suppression effect that makes it difficult for the zero-phase current to flow in the electric path, but it is desirable that the zero-phase current suppression reactor 1 does not interfere with the current of components other than the zero-phase current. However, if the magnetic coupling of the winding conductor 2 of each phase is uneven, the effect of suppressing the zero-phase current in the electric path may be reduced, or the current of a component other than the zero-phase current may be hindered.

Therefore, in the present embodiment, by making the magnetic coupling of each winding conductor 2 uniform, the effect of suppressing the zero-phase current can be improved, and the current of components other than the zero-phase current may be hindered. Can be reduced.

FIG. 4 shows an equivalent circuit of the zero-phase current suppression reactor 1. Here, the zero-phase current (i0) is in-phase for each arbitrary frequency included in the current (iu, iv, iw) flowing through the winding conductor 2 of each phase, as shown by the following equation (1). Moreover, it is the total of the components of the same size.

Further, there are roughly the following two specifications required for the zero-phase current suppression reactor 1.
(1) Minimize the zero-phase current (i0).
(2) Minimize the inductance for currents other than the zero-phase component.

In this case, if the inductances (Lu, Lv, Lw) of each phase are made equal, more specifically, the mutual inductance between the U phase and the V phase represented by the following equations (2) to (4) (Muv), the mutual inductance between the V phase and the W phase (Mvw), and the mutual inductance between the W phase and the U phase (Mwoo) can be equalized to satisfy the above specifications.

Then, in order to satisfy the above equations (2) to (4), as shown in FIG. 1, the winding conductor 2 has the winding start end and the winding end end at the same position in the circumferential direction. It is sufficient to wind the coil so that the winding start end is arranged in 3 equal parts in the circumferential direction. More specifically, as is clear from FIG. 1, the U-phase winding conductor 2u is geometrically 6 turns + 1/3 turns + 1/3 turns = 6 + 2/3 turns with the V-phase winding conductor 2v. In addition to being in parallel, the W-phase winding conductor 2w is also geometrically parallel by 6 + 2/3 turns.

Similarly, the V-phase winding conductor 2v is geometrically parallel to the U-phase winding conductor 2u by 6 + 2/3 turns, and is geometrically 6 + 2 with the W-phase winding conductor 2w. Only 3 turns are in parallel. Further, the W-phase winding conductor 2w is geometrically parallel to the U-phase winding conductor 2u by 6 + 2/3 turns, and the V-phase winding conductor 2w is also geometrically 6 + 2 /. Only 3 turns are in parallel.

That is, each winding conductor 2 has the same length of the portion in parallel with the other two-phase winding conductor 2 for 6 + 2/3 turns. By making the geometric arrangements of the winding conductors 2 equal in this way, the magnetic coupling between the winding conductors 2 is made uniform. Then, if the magnetic coupling between the winding conductors 2 is made uniform, the mutual inductances (Muv, Mvw, Mwoo) of the respective winding conductors 2 become equal, and the inductances (Lu, Lv, Lw) of each phase become equal. As a result, the zero-phase current suppression reactor 1 can satisfy the required specifications (1) and (2).

According to the embodiment described above, the following effects can be obtained.

In the zero-phase current suppression reactor 1, each winding conductor 2 has the winding start end and the winding end end at the same position in the circumferential direction, and the winding start end is in a position where the winding start end is arranged in three equal positions in the circumferential direction. It is wound so that the lengths of the portions parallel to the other winding conductor 2 are equal to each other.

As a result, the winding conductors 2 of each phase have the same geometrical arrangement with respect to the other winding conductors 2, and the mutual inductances are the same, so that the magnetic coupling between the winding conductors 2 is made uniform. To. As a result, the inductances (Lu, Lv, Lw) of each phase become equal and satisfy the specifications required for the zero-phase current suppression reactor 1, so that the zero-phase current suppression effect can be improved and the zero-phase current suppression effect can be improved. It is possible to reduce the possibility of hindering the current of components other than the current.

Further, according to the winding structure described above, the state in which the geometrical arrangements with respect to the other winding conductors 2 are equalized is set to minimize the axial length, that is, the height dimension of the zero-phase current suppression reactor 1. It can be realized in such a state, and miniaturization can be achieved.

Further, the winding conductor 2 can also be wound around the leg portion 3a of the iron core such as the bipod iron core 3. As a result, the magnetic resistance can be lowered, the magnetic flux can be increased, and the inductance can be increased. Further, by providing a gap in the iron core, magnetic saturation is relaxed and a constant inductance can be obtained. Further, by electrically connecting the winding conductors 2 of the legs 3a in series or in parallel, it is possible to meet various required specifications.

Further, the winding start end and the winding end end of the winding conductor 2 are at the same position in the circumferential direction, and the winding start end is at a position where the winding start end is arranged in three equal parts in the circumferential direction. Even if the windings are wound so that the lengths of the parallel portions are equal to each other, the effect of suppressing the zero-phase current is to be improved as in the case of the zero-phase current suppression reactor 1 of the embodiment. At the same time, it is possible to reduce the possibility of hindering the current of components other than the zero-phase current, and it is possible to obtain the same effect such as miniaturization.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

In the drawing, 1 is a zero-phase current suppression reactor and winding, 2 is a winding conductor, 3 is a bipod core (iron core), 3a is a leg, and CL is a virtual line.

Claims (5)

It is a zero-phase current suppression reactor in which three winding conductors connected to each of the three-phase electric circuits are wound side by side in the axial direction.
In each of the winding conductors, the winding start end and the winding end end located at both ends in the axial direction are at the same position in the circumferential direction, and the winding start end is in a position where the winding start ends are arranged in three equal parts in the circumferential direction. , A zero -phase current suppression reactor that is wound so that the lengths of the portions parallel to the other winding conductors in the axial direction are equal to each other. The zero-phase current suppression reactor according to claim 1, wherein the winding conductor is wound around the outer periphery of the iron core. The winding conductor is wound around each leg of the bipod iron core.
The zero-phase current suppression reactor according to claim 1 or 2, wherein the winding conductor of each leg is electrically connected in series or in parallel. The winding conductor is wound around each leg of the bipod iron core.
One of the winding conductors wound around each leg has a winding start end and a winding end end located on a virtual line passing through the center of the two legs and outside each leg. The zero-phase current suppression reactor according to any one of claims 1 to 3, which is arranged so as to be used. It is a winding in which three winding conductors connected to each of the three-phase electric circuits are wound side by side in the axial direction.
In each of the winding conductors, the winding start end and the winding end end located at both ends in the axial direction are at the same position in the circumferential direction, and the winding start end is in a position where the winding start ends are arranged in three equal parts in the circumferential direction. , The winding is wound so that the lengths of the portions parallel to the other winding conductors in the axial direction are equal to each other.

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