JPWO2013065095A1 - Reactor, transformer and power converter using the same - Google Patents

Abstract

A reactor or a transformer includes two opposing yoke iron cores and a plurality of magnetic leg iron cores around which coils are wound and provided with gap adjusting means, and the two opposing yoke iron cores are Are connected by the plurality of magnetic leg iron cores, and at least one of the connecting portions has an isotropic magnetic body made of an isotropic magnetic material. The power converter includes the reactor or the transformer.

Description

  The present invention relates to a reactor and a transformer using a composite iron core, and a power converter using the same.

In general, iron cores of magnetic components such as large-capacity reactor devices and transformers are made of laminated iron cores made up of multiple thin ribbon-like magnetic materials such as thin silicon steel plates and amorphous materials to reduce operating loss (iron loss). Composed.
The iron core of the magnetic component is formed of a magnetic path through which a magnetic flux passes by combining a plurality of laminated iron cores, and includes a magnetic leg portion around which a coil is wound and a yoke portion that connects the magnetic legs. When a current is passed through the coil, if there is a location where the direction of the magnetic flux passing through the laminated iron core does not match the in-plane direction of the ribbon-like magnetic material, an eddy current is induced in the plane of the ribbon at that location. . As a result, eddy current loss occurs in the iron core, and the iron loss of the magnetic component increases.
As a method for suppressing the occurrence of this eddy current loss, there is, for example, Patent Document 1. Patent Document 1 discloses a technique in which a directional electromagnetic steel sheet is used for a leg portion to be wound, and any one of a dust core, a sintered magnetic core, and a non-oriented electrical steel sheet is used for a yoke part. ing.

JP 2009-117442 A

If the same magnetic material is used for the yoke iron core and the magnetic leg iron core as in the prior art, as described above, there is a problem that eddy current loss occurs in the iron core and the iron loss of the magnetic component increases.
Further, in the reactor device having the configuration shown in Patent Document 1 (hereinafter simply referred to as “reactor” as appropriate), the yoke core and the magnetic leg core need to be made of different magnetic materials. When used as an iron core for a reactor having a capacity or an iron core for a transformer, a large amount of two kinds of magnetic materials are used, resulting in an increase in manufacturing cost.
In addition, when a dust core or sintered core is used as the material for the yoke core, the size that can be produced is limited, so it is difficult to apply it to a large capacity reactor device or transformer core. There is a problem that.

  Therefore, the present invention solves such problems, and an object of the present invention is to provide a reactor or a transformer with low manufacturing cost and excellent low-loss characteristics, and a power converter using the same. It is to be.

In order to achieve the above object, each invention is configured as follows.
That is, the reactor of the present invention includes two opposing yoke iron cores and a plurality of magnetic leg iron cores around which the coil is wound and provided with gap adjusting means, and the two opposing yoke iron cores are The plurality of magnetic leg iron cores are connected, and at least one of the connecting portions has an isotropic magnetic body made of an isotropic magnetic material.
The transformer of the present invention includes two opposing yoke iron cores and a plurality of magnetic leg iron cores wound with coils and provided with gap adjusting means. The two opposing yoke iron cores are The plurality of magnetic leg iron cores are connected, and at least one of the connecting portions has an isotropic magnetic body made of an isotropic magnetic material.
Moreover, the power converter of this invention is equipped with the said reactor or the said transformer.
Other means will be described in the embodiment for carrying out the invention.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing cost is low, and the reactor or the transformer excellent in the low-loss characteristic and a power converter using the same can be provided.

It is a perspective view which shows the structure of the reactor of 1st Embodiment of this invention. It is a longitudinal section showing the structure of the reactor of a 1st embodiment of the present invention. It is a longitudinal cross-sectional view which shows the structure of the transformer of 2nd Embodiment of this invention. It is the figure which showed the definition of the structure, a dimension, magnetic flux characteristic, and a coordinate system at the time of verifying the effect of this embodiment by the electromagnetic field calculation by a finite element method, (a) is the yoke iron core 1a and the magnetic leg iron core 3 is a diagram showing the structure, dimensions, and coordinate system of the connecting portion of FIG. 3, (b) is a vector diagram of magnetic flux B in the magnetic leg core 3 near the connecting portion, and (c) is a connecting portion of the yoke core 1a and the magnetic leg core 3. It is a coordinate system and a perspective view. In the iron core of the present embodiment having the structure and dimensions shown in FIG. 4, the distribution of the θ direction component of the magnetic flux on the connecting surface of the magnetic leg iron core 3 and the disc-shaped isotropic magnetic body 4 is calculated by electromagnetic field calculation by the finite element method. It is the calculated | required characteristic view. In the reactor of 3rd Embodiment of this invention, a magnetic leg iron core is a figure which shows the structure which is carrying out the substantially fan shape laminated | stacked, insulating several strip-shaped magnetic material. In the reactor of 4th Embodiment of this invention, a magnetic leg iron core is a figure which shows the structure which is carrying out the substantially rectangular parallelepiped shape laminated | stacked, insulating several strip-shaped magnetic material. In the reactor of 5th Embodiment of this invention, it is a figure which shows the structure of the fixing device of a reactor. It is a figure which shows the structure which provided the reactor of this embodiment in the power converter of the power converter of 6th Embodiment of this invention. It is a reference figure showing the outline of the structural example of the conventional reactor.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(First embodiment, reactor)
A first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
FIG. 1 is a perspective view showing the structure of the reactor (reactor device, three-phase reactor device) of the first embodiment. Moreover, it is also a perspective view which shows the structure of the transformer (transformer apparatus, three-phase transformer apparatus) of 2nd Embodiment mentioned later.
FIG. 2 is a longitudinal sectional view showing the structure of the reactor of the first embodiment.

In FIG. 1, yoke iron cores 1a and 1b are formed by laminating a plurality of ribbon-like magnetic materials while being insulated and wound in a substantially toroidal shape (annular shape).
The magnetic leg iron core 3 is formed by laminating a ribbon-like magnetic material while being insulated and winding it in a substantially cylindrical shape. The magnetic leg iron core 3 is provided with a longitudinal slit 3a in at least one place of a substantially cylindrical shape. Also, at least one or more gap adjustment means 5 (gap, gap) are provided.
The three magnetic leg cores 3 are arranged on the circumference at an angle of 120 degrees with each other, and connect the two yoke cores 1a and 1b. The reason why the three magnetic leg cores 3 are arranged in the above-described positional relationship is to allow the reactor device of the present embodiment to function as a three-phase reactor for three-phase alternating current. This is to ensure the sex.

An isotropic magnetic body 4 is sandwiched between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b.
The isotropic magnetic body 4 is a substantially thin plate-shaped component made of an isotropic magnetic material, and is composed of a dust core having a magnetic metal as a main component or a sintered core such as ferrite. This is because the material that has undergone the compacting and sintering process has a form close to polycrystal and is easily characterized by isotropic properties.

In FIG. 1, yoke iron cores 1a and 1b, isotropic magnetic body 4, and magnetic leg iron core 3 are shown separately. Further, the arrows in FIG. 1 indicate that the yoke iron cores 1a, 1b and the isotropic magnetic body 4 are connected when the yoke iron cores 1a, 1b, the isotropic magnetic body 4 and the magnetic leg iron core 3 are assembled and connected (joined). It roughly shows the corresponding part.
1 is a “composite iron core” including the magnetic leg iron core 3, the slit 3a, the isotropic magnetic body 4, and the gap adjusting means 5, as described above. In this case, it is simply written as “iron core” as appropriate.
In FIG. 1, the description of the coil 2 shown in FIG. 2 is omitted for convenience of description.

In FIG. 2, the yoke iron cores 1a and 1b, the magnetic leg iron core 3, the isotropic magnetic body 4, and the gap adjusting means 5 are the same as those described with reference to FIG. is there.
However, in FIG. 1, the yoke cores 1a and 1b, the isotropic magnetic body 4, and the magnetic leg core 3 are shown separately, but in FIG. 2, the yoke cores 1a and 1b and the isotropic magnetic body are shown. 4 and the magnetic leg iron core 3 are in contact with each other and indicate the assembled state.
Further, only two magnetic leg cores 3 are shown for convenience of description.
In FIG. 2, the coil 2 is wound in the circumferential direction of the substantially cylindrical shape of the magnetic leg iron core 3. This configuration electrically realizes a basic structure of a reactor in which a coil is wound around an iron core having a high magnetic permeability.
The coil 2 is an exciting coil and is composed of a linear conductor provided with an insulating member or a plate-like conductor.

When a current is passed through the coil (excitation coil) 2, a magnetic flux is generated in the longitudinal direction of the substantially cylindrical shape of the magnetic leg iron core 3, and an eddy current flows in the circumferential direction of the magnetic leg iron core 3 due to the magnetic flux. As the loss increases. Therefore, in order to prevent this eddy current from flowing or occurring, the slit 3 a described above is provided in at least one place in the longitudinal direction of the magnetic leg core 3.
Further, in order to prevent a change in inductance value and an increase in loss due to magnetic saturation of the magnetic leg iron core 3, as shown in FIG. 2 (and FIG. 1), the magnetic leg iron core 3 has at least one or more gap adjustments as described above. Means 5 are provided. In order to obtain desired characteristics (saturation characteristics, inductance value) as a reactor, the gap of the gap adjusting means 5 is adjusted during assembly.

The direction of the magnetic flux flowing through the connection between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b greatly changes, so that the magnetic flux travels through the ribbon surface constituting the iron core, and an eddy current is induced in the ribbon surface. The In order to reduce this eddy current, an isotropic magnetic body 4 is provided.
The isotropic magnetic body 4 is located between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b, and isotropic when the magnetic flux direction of the magnetic leg iron core 3 changes approximately 90 degrees to the magnetic flux direction of the yoke iron cores 1a and 1b. Changes in the direction of magnetic flux are handled inside the isotropic magnetic body 4 due to the characteristics of the magnetic material.
As a result, the change in magnetic flux in the magnetic leg core 3 and the yoke cores 1a and 1b is reduced, the generation of eddy currents in the magnetic leg core 3 is suppressed, and eddy current loss can be reduced.
A major feature of this embodiment is that the isotropic magnetic body 4 is provided between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b.
Details of the change in magnetic flux in the isotropic magnetic body 4 will be described later.

(Second embodiment, transformer)
A second embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is also a perspective view showing the structure of the transformer (transformer device, three-phase transformer device) of the second embodiment, as described above. However, in the second embodiment, the gap adjusting means 5 is not an essential element and is not shown in FIG.
In the case of a large transformer, the gap adjusting means 5 may be provided as shown in FIG.
FIG. 3 is a longitudinal sectional view showing the structure of the transformer (transformer device, three-phase transformer device) of the second embodiment.
In FIG. 3, the yoke iron cores 1a and 1b, the magnetic leg iron core 3, and the isotropic magnetic body 4 are the same as those described in FIG. 1, which is a perspective view, and are shown in a longitudinal section.

In FIG. 3, the primary coil 2 a is wound in the circumferential direction of the substantially cylindrical shape of the magnetic leg core 3. Further, a secondary coil 2b is wound around the circumference in the circumferential direction. The primary coil 2a and the secondary coil 2b are comprised from the linear conductor provided with the insulating member, or a plate-shaped conductor.
At this time, the primary coil 2a serves as an exciting coil, and the exciting coil is particularly preferably configured as a linear conductor or a plate conductor provided with an insulating member.
In the following, even when a transformer (transformer device, three-phase transformer device) indicates a device, it is simply abbreviated as “transformer”.

In FIG. 3, when a current is passed through the primary coil 2a, a current in the direction opposite to that of the primary coil 2a is induced in the secondary coil 2b in accordance with the magnitude of the load connected to the electrode of the coil. Since the action of canceling or weakening the magnetic flux in the leg iron core 3 appears, magnetic saturation hardly occurs.
Therefore, it is not always necessary to provide the gap adjusting means (5, FIG. 2) in the magnetic leg core 3. That is, in FIG. 3, the magnetic leg iron core 3 does not have a gap adjusting means (5, FIG. 2), is formed into an integral substantially cylindrical shape, and is arranged so as to connect the yoke iron cores 1a and 1b.
However, as described above, in the case of a large transformer, a gap adjusting means (5, FIG. 1, FIG. 2) may be provided.
Also in the case of FIG. 3, by providing the isotropic magnetic body 4 between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b, generation of eddy current in the magnetic leg iron core 3 is suppressed, and eddy current loss is reduced. .

≪Effect of isotropic magnetic material≫
Next, the effect of providing the isotropic magnetic body 4 between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b in the first embodiment and the second embodiment will be described with reference to FIGS.
FIG. 4 is a diagram showing the definition of the structure, dimensions, magnetic flux characteristics, and coordinate system when the effect of the present embodiment is verified by the electromagnetic field calculation by the finite element method. FIG. The figure which shows the structure of the connection part of the magnetic leg iron core 3, a dimension, and a coordinate system, (b) is a vector diagram of the magnetic flux B in the magnetic leg iron core 3 near a connection part, (c) is the yoke iron core 1a, and a magnetic leg iron core 3 is a perspective view and a coordinate system of a connecting portion of FIG.

In FIG. 4, a cylindrical coordinate system is defined in which the circumferential direction of the yoke core 1a is θ, the radial direction is r, and the axial direction of the magnetic leg core 3 is z.
Further, as shown in FIGS. 4A and 4C, a disk-shaped isotropic magnetic body 4 having a thickness t and a diameter D is sandwiched between connecting portions of the yoke iron core 1a and the magnetic leg iron core 3. Yes. The diameter of the disc-shaped isotropic magnetic body 4 and the magnetic leg iron core 3 are substantially the same, the thickness of the yoke iron core 1a is 0.4 times the diameter D of the disk-shaped isotropic magnetic body 4, and the width is It is substantially the same as the diameter D. The diameter of the hollow portion inside the magnetic leg core 3 is 0.1 times the diameter D of the isotropic magnetic body 4.
Note that the diameter (D) of the disk-shaped isotropic magnetic body 4 and the width (D) of the yoke iron core 1a are equal to the width of the yoke iron core 1a (that is, the diameter of the magnetic leg core 3 (that is, the disk-shaped isotropic magnetic body). This corresponds to the fact that the diameters of 4) almost overlap.

The magnetic flux B from the magnetic leg iron core 3 toward the yoke iron core 1a passes through the disk-shaped isotropic magnetic body 4 and follows the path shown by the arrow shown in FIG. The path of the magnetic flux B indicated by the arrow causes a change in direction inside the magnetic leg iron core 3 near the yoke iron core 1a.
That is, as shown in FIG. 4B, the magnetic flux B inside the magnetic leg core 3 in the vicinity of the yoke core 1a is affected by the change in its direction, and therefore has a θ-direction component in addition to the z-direction component. Become.
Since the magnetic leg iron core 3 is formed by winding a ribbon-shaped magnetic material having the z direction in-plane in a substantially cylindrical shape, the θ-direction component B _θ of the magnetic flux B penetrates the ribbon and generates eddy current loss. Cause.
On the other hand, since the direction of the magnetic flux in the yoke core 1a is parallel to the ribbon surface, almost no eddy current loss occurs.
In FIG. 4A, since a hollow portion exists in the center of the magnetic leg iron core 3, it is closer to “cylindrical” than “columnar”, but ideally, it is desirable that there is no hollow portion. Darely written as “columnar”.

≪Result of electromagnetic field calculation by finite element method≫
FIG. 5 shows the magnetic flux along the center line aa ′ in the θ direction at the connection surface between the magnetic leg iron core 3 and the disk-shaped isotropic magnetic body 4 in the iron core of this embodiment having the structure and dimensions shown in FIG. 6 is a characteristic diagram obtained by calculating the distribution of absolute values | B _θ | of the θ direction components of the electromagnetic field by the finite element method.
In FIG. 5, the horizontal axis represents the position on the center line aa ′ in the θ direction on the connection surface of the magnetic leg core 3 and the disk-shaped isotropic magnetic body 4, and the vertical axis represents the absolute value of the θ direction component of the magnetic flux | B _θ | (unit: [T] (T: Tesla, Tesla, magnetic flux density)).
5, the portion that is blank and has no data value corresponds to the hollow portion in the center of the magnetic leg core 3 in FIG. 4. This hollow portion is an area excluded from the calculation because there is no iron core.

In this calculation, the diameter D of the disk-shaped isotropic magnetic body 4 shown in FIG. 4 is made constant, the thickness t of the disk-shaped isotropic magnetic body 4 is changed, and the disk-shaped isotropic magnetic body 4 exists. Not (t / D = 0.08), t / D = 0.08, t / D = 0.16, t / D = 0.25, t / D = 0.29, t / D = 0 Up to .45, the thickness t of the isotropic magnetic body 4 is gradually increased, and six calculation (simulation) results are shown with t / D as a parameter.
In FIG. 5, these six calculation results are shown as characteristic lines by various notations such as a solid line, a broken line, and a one-dot chain line.
The magnetomotive force of the coil is determined such that the average value of the z-direction component Bz of the magnetic flux inside the magnetic leg core 3 is 0.82 [T]. The magnetic saturation characteristics of the magnetic leg iron core 3, the yoke iron core 1a, and the isotropic magnetic body 4 were calculated on the assumption that they were all the same as that of the Metglas amorphous ribbon 2605SA1 manufactured by Hitachi Metals.

When the disk-shaped isotropic magnetic body 4 does not exist, that is, t = 0, and therefore t / D = 0, the absolute value of the θ direction component of the magnetic flux in the above six calculation (simulation) results | The maximum value of B _θ | is obtained.
This is because, when the isotropic magnetic body 4 is not present, | B _θ | increases in the vicinity of the outermost peripheral portion of the magnetic leg core 3 and the inner hollow portion, and the magnetic flux penetrates the ribbon surface of the ribbon magnetic material. It is estimated that this is a particularly remarkable result of the tendency of eddy current loss to increase.
On the other hand, the conditions of t / D = 0.08, t / D = 0.16, and t / D = 0.25 in FIG. 5 correspond to increasing the thickness t of the disk-shaped isotropic magnetic body 4. Then, as the value of t / D increases, | B _θ | decreases.
This corresponds to an increase in | B _θ | at the connection surface between the magnetic leg core 3 and the isotropic magnetic body 4 being suppressed by increasing the thickness t of the disk-shaped isotropic magnetic body 4. .

Under the condition of t / D = 0.29, the increase in | B _θ | in the vicinity of the outermost peripheral portion of the magnetic leg core and the inner hollow portion is almost eliminated, and under the condition of t / D = 0.45. It can be seen from the characteristic diagram of FIG. 5 that | B _θ | is further reduced.
Therefore, at t / D = 0.29 or more, it can be expected that the occurrence of eddy current loss in the magnetic leg core 3 is substantially suppressed.
That is, the larger the thickness (t) of the isotropic magnetic body 4 means the greater the effect.
In addition, the above effect is similarly effective in a reactor or a transformer.

(Third embodiment, reactor)
Next, a third embodiment (reactor) of the present invention will be described.
FIG. 6 shows a structure in which a magnetic leg core 3 around which a coil 2 is wound has a substantially fan shape in which a plurality of ribbon-like magnetic materials are laminated while being insulated in a third embodiment of the present invention. FIG.
In FIG. 6, only one magnetic leg iron core 3 is shown, but three magnetic leg iron cores may be used as shown in FIG. FIG. 6 is different from FIG. 1 in that the magnetic leg iron core 3 has a substantially fan shape.
The substantially fan-shaped magnetic leg core 3 is formed, for example, by cutting a toroidal core 1c formed by laminating a thin strip-shaped magnetic material while being insulated and wound in a toroidal shape at an appropriate angle in the radial direction. Is done.

  Since the magnetic leg iron core 3 in FIG. 6 is substantially fan-shaped, when the magnetic leg iron core 3 is composed of three pieces compared to the magnetic leg iron core 3 in FIG. The occupied area efficiency of the magnetic leg iron core 3 in the center of the book is improved. Further, when the magnetic leg iron core 3 is substantially fan-shaped, the lamination direction of the ribbon-like magnetic material of the yoke iron cores 1a and 1b and the magnetic leg iron core 3 is easily matched, and when the three-phase reactor device is obtained, It is characterized by a compact structure and low loss characteristics.

In addition, when the magnetic leg iron core 3 is substantially fan-shaped, the connecting portion between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b is substantially fan-shaped and has the same cross-sectional shape as the magnetic leg iron core 3. A thin plate-shaped isotropic magnetic body 4 is provided.
It should be noted that the laminating direction of the ribbon-like magnetic material of the magnetic leg core 3 is the same as the laminating direction of the yoke cores 1a and 1b, and it is desirable from the viewpoint of improving the electrical characteristics to be the radial direction.
Moreover, although 3rd Embodiment demonstrated as a reactor apparatus, if the primary coil 2a (FIG. 3) and the secondary coil 2b (FIG. 3) are provided, the transformer which has the structure of the same magnetic leg iron core 3, or three A phase transformer can be configured.
The elements other than that the magnetic leg iron core 3 is substantially fan-shaped are, for example, approximately 120 degrees on the circumference of the yoke iron cores 1a and 1b and the yoke iron cores 1a and 1b, except for those described above. 6 and FIG. 1 are the same regarding the arrangement at the angle and the gap adjustment means 5, and a duplicate description will be omitted.

(Fourth embodiment, reactor)
Next, a fourth embodiment (reactor) of the present invention will be described.
FIG. 7 shows a fourth embodiment of the present invention, in which the magnetic leg iron core 3 around which the coil 2 is wound has a substantially rectangular parallelepiped shape in which a plurality of ribbon-shaped magnetic materials 1d are laminated while being insulated. It is a figure which shows a structure.
Although only one magnetic leg core 3 is shown in FIG. 7, three magnetic leg iron cores may be used as shown in FIG. FIG. 7 differs from FIGS. 1 and 6 in that the magnetic leg iron core 3 has a rectangular parallelepiped shape.
The substantially rectangular parallelepiped magnetic leg iron core 3 is formed, for example, by cutting a thin strip-shaped magnetic material 1d laminated while being insulated into a predetermined size. By adopting a rectangular parallelepiped shape, the reactor device may be reduced in size, the number of steps in the manufacturing process may be reduced, and the manufacturing cost may be reduced.

In addition, since the magnetic leg iron core 3 has a substantially rectangular parallelepiped shape, the connecting portion between the magnetic leg iron core 3 and the yoke iron cores 1a and 1b has a substantially rectangular parallelepiped shape having the same cross-sectional shape as the magnetic leg iron core 3. A thick thin plate-shaped isotropic magnetic body 4 is provided.
The laminating direction of the ribbon-like magnetic material of the magnetic leg core 3 is preferably the same as the laminating direction of the yoke cores 1a and 1b, and is preferably the radial direction.
Moreover, although 3rd Embodiment was demonstrated as a reactor, if the primary coil 2a (FIG. 3) and the secondary coil 2b (FIG. 3) are provided, the transformer which has the structure of the same magnetic leg iron core 3, or three A phase transformer can be configured.
Since elements other than the magnetic leg iron core 3 having a substantially fan shape are the same as those shown in FIGS. 7 and 1 except for those described above, redundant description will be omitted.

(Fifth embodiment / reactor)
Next, a fifth embodiment (reactor, reactor device) of the present invention will be described.
FIG. 8 is a diagram illustrating the structure of the fixing device of the reactor device in the fifth embodiment of the present invention. Note that the first, third, and fourth embodiments described above can be applied to the reactor device itself other than the structure of the fixing device.
In FIG. 8, the reactor devices (1a, 1b, 2, 3, 4, 5) are mounted on a pedestal 7, covered with a fixing jig 6 from above, and fixed by pressure by fixing means 8a, 8b.
The pedestal 7 and the fixing jig 6 may be constituted by a plate-like member that completely covers the reactor device, or may be constituted by a frame-like member that does not completely cover the reactor device.
Moreover, you may provide the cooling means 9 on the concentric axis | shaft of the yoke iron cores 1a and 1b as needed.
In the above, FIG. 8 shows an example of the reactor device (1a, 1b, 2, 3, 4, 5) in which a plurality of gap adjusting means 5 are provided in the magnetic leg core 3, but in this embodiment, The structural example of the fixing device shown can be applied to the transformer device according to the second embodiment shown in FIG. 3 with the same configuration.

(Sixth embodiment-power converter)
Next, as a sixth embodiment of the present invention, a power converter using the reactor of the above-described embodiment will be described.
FIG. 9 is a circuit diagram showing the configuration of the power converter according to the sixth embodiment of the present invention, in which the reactor shown in the first embodiment and the third to fifth embodiments is applied to the power converter. The circuit diagram shown in FIG. 9 shows a circuit configuration of a power converter as a three-phase uninterruptible power supply device of a constant inverter power supply system.
In FIG. 9, the power converter is provided between the AC power supply 13 and the load 14.
Further, the power converter includes a rectifier circuit 11 that converts AC power of the AC power supply 13 into DC power, and an inverter circuit 12 that converts DC power into AC power having an arbitrary voltage and an arbitrary frequency. A smoothing capacitor 22 and a chopper circuit 15 are connected between the output terminal of the rectifier circuit 11 and the input terminal of the inverter circuit 12.

The rectifier circuit 11 is an AC / DC in which a filter circuit 24 having a three-phase reactor 20 and a three-phase capacitor 21 and a plurality of IGBT (Insulated Gate Bipolar Transistor) switching elements 17 that are semiconductor elements are bridge-connected. And a conversion circuit 23 (bridge circuit).
The inverter circuit 12 includes a DC / AC conversion circuit 27 (bridge circuit) in which a plurality of IGBT switching elements 17 are bridge-connected, and a filter circuit 24 having a three-phase reactor 20 and a three-phase capacitor 21. Configured.
Note that the switching elements 17 composed of a plurality of IGBTs in the AC / DC conversion circuit 23 and the DC / AC conversion circuit 27 are each subjected to PWM (Pulse Width Modulation) control in an integrated manner from the gate terminals, and each of the desired functions described above. Fulfill.
Further, a diode for protecting overvoltage is added or parasitic to each of the IGBT switching elements 17 and connected in antiparallel.

Moreover, the reactor in any one of 1st Embodiment and 3rd-5th Embodiment is used for the reactor 20 for three phases which the filter circuit 24 with which the rectifier circuit 11 and the inverter circuit 12 were equipped.
The chopper circuit 15 includes a switching element 25 including two IGBTs (25) connected in series, and is connected between both terminals of the smoothing capacitor 22. One end of a coil or reactor 26 is connected to the connection point of the two switching elements 25, and the battery 16 is connected between the other end of the coil or reactor 26 and the emitter of one switching element 25.

In the above power converter, during normal operation, AC power from the AC power source 13 is converted into DC power by the rectifier circuit 11, and direct current is converted again by the inverter circuit 12, and AC of an arbitrary voltage and an arbitrary frequency suitable for the load 14. And is sent to the load 14.
Further, as an operation that is not during normal operation (operation 1 other than normal operation), when the power supply from the AC power supply 13 is cut off, the battery 16 and the inverter circuit 12 are connected by the action of the chopper circuit 15 and the load 14 Is continuously supplied with power from the battery 16 converted into AC power by the inverter circuit 12.
In addition, as an operation at the time of maintenance or the like (operation 2 other than normal operation), a bypass circuit 18 provided with a bypass converter circuit 19 is connected, and the AC power supply 13 is not connected via the rectifier circuit 11 or the inverter circuit 12. AC power is supplied to the load 14 via the bypass circuit 18.
Note that how much function the bypass circuit 18 provided with the bypass converter circuit 19 has depends on the specifications of the power converter.

As described above, the rectifier circuit 11 has a function of an AC / DC conversion circuit that converts three-phase AC power into DC power, and the inverter circuit 12 has three-phase AC power of an arbitrary voltage and an arbitrary frequency. It has a function of a DC / AC conversion circuit for converting to.
In these conversions, the rectifier circuit 11 and the inverter circuit 12 both operate a plurality of switching elements that perform PWM control. In the process of these switching operations, harmonic components (ripple components) are generated.
Removal of these generated harmonic components and impedance between the AC power supply 13 and the AC / DC conversion circuit 23 constituting the bridge circuit, and between the load 14 and the DC / AC conversion circuit 27 constituting the bridge circuit. A filter circuit 24 is used for matching.

As described above, the filter circuit 24 is configured by using the three-phase reactor 20 and the three-phase capacitor 21. The reactor (device) according to any one of the first embodiment and the third to fifth embodiments of the present invention described above is used for the three-phase reactor 20.
By using the reactor of the present embodiment, a power converter that has excellent low loss characteristics and low manufacturing costs can be realized and provided.

(Other embodiments)
The present invention is not limited to the embodiment described above. Here are some examples:

  1 to 3, 6, and 7, the embodiment in which the isotropic magnetic body 4 is provided between the magnetic leg iron core and both the yoke iron core 1 a and the yoke iron core 1 b is shown. Even if the isotropic magnetic body 4 is provided only on one side of the iron core 1a side or only on the yoke iron core 1b side, it is effective in reducing eddy current loss.

  The magnetic leg iron core 3 shown in the embodiment of FIGS. 1, 6, and 7 is an example of a cylindrical shape, a fan shape, and a rectangular parallelepiped shape formed by laminating thin ribbon magnetic materials. You may comprise a reactor apparatus by arbitrary combinations of a magnetic leg iron core.

  Further, in FIG. 6 showing the third embodiment, as a method of forming the magnetic leg iron core 3 having a substantially sector shape, “a steel core formed by winding a ribbon-like magnetic material in a toroidal shape while applying insulation is appropriately used. “It cuts in the radial direction at a certain angle”, but other methods may be used as long as the substantially fan-shaped shape shown in FIG. 6 is obtained.

  In FIG. 6, the third embodiment, that is, the effect that the magnetic leg iron core 3 of the reactor is substantially fan-shaped is described, but this effect is also the same as that of the magnetic leg iron core of the transformer.

  In FIG. 7, the effect of the fourth embodiment, that is, the effect that the magnetic leg iron core 3 of the reactor has a substantially rectangular parallelepiped shape is described, but this effect is the same as that of the magnetic leg iron core of the transformer.

  Further, although the three-phase reactor device of FIG. 1 shows only three magnetic legs, a zero-phase magnetic leg as a path for flowing a magnetic flux due to zero-phase impedance between each of the three magnetic legs. Even in a three-phase reactor device provided with an iron core (not shown), providing an isotropic magnetic body between the magnetic leg iron core and the yoke iron core is effective in reducing eddy current loss.

  In addition, although the reactor device of FIG. 1 shows three magnetic legs for three-phase use, it is not limited to three-phase, and when it exceeds three phases (for example, five phases), a plurality of more than three Even in a reactor device having a magnetic leg, providing an isotropic magnetic body between the magnetic leg iron core and the yoke iron core is effective in reducing eddy current loss.

Although the switching element 17 of the semiconductor element constituting the AC / DC conversion circuit 23 and the DC / AC conversion circuit 27 in the power converter shown in FIG. 9 is an IGBT, it is not limited to an IGBT.
You may comprise by MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) which is a switching element of a semiconductor element, a bipolar transistor (Bipolar junction transistor), and BiCMOS (Bipolar Complementary Metal Oxide Semiconductor).

  Although the example of the uninterruptible power supply is shown in FIG. 9 as an application of the reactor device of the embodiment of the present invention, the invention is not limited to this. By using the reactor device of the present invention in the filter circuit of the power converter for other applications using the bridge circuit, it is possible to provide a low-loss power converter.

  Moreover, in FIG. 9, although the example which equips a power converter with the reactor apparatus of this embodiment was shown, it is also possible to equip a power converter with the transformer of this embodiment.

<Reference example of a conventional reactor device>
FIG. 10 is a reference diagram showing an outline of a longitudinal section of the structure of a conventional reactor (reactor device).
In FIG. 10, a reactor device is constituted by the yoke iron core 31, the magnetic leg iron core 30, the gap adjusting means 32, and the coil 2.
The magnetic leg iron core 30 and the yoke iron core 31 are connected directly or via a gap. Accordingly, the magnetic flux generated by the current flowing through the coil 2 is in the vertical direction in the magnetic leg core 30 but in the horizontal direction in the yoke core 31, so that the vicinity of the connection portion between the magnetic leg iron core 30 and the yoke iron core 31. In the magnetic leg iron core 30, a horizontal direction magnetic flux is generated in addition to the vertical direction magnetic flux, eddy current flows in the circumferential direction of the magnetic leg iron core 3, and the loss as a reactor increases.
That is, in the structure of the conventional reactor (reactor device) shown in FIG. 10, loss due to generation of eddy current was large.

(Supplement of the present invention and this embodiment)
As described above, according to the present invention, by providing an isotropic magnetic body between the magnetic leg iron core and the yoke iron core, generation of eddy current in the magnetic leg iron core is prevented and reduction of eddy current loss generated in the iron core is realized. doing. Therefore, as described above, a reactor or transformer having a low manufacturing cost and a low loss characteristic compared to a reactor or transformer using a conventional composite iron core and a power converter using the same are provided. It becomes possible.
Moreover, it is not necessary to use a dust core or a sintered magnetic core as a material for the yoke core as in Patent Document 1 which is the prior art, so that an iron core that is easy to manufacture and that can handle a large capacity is manufactured. It is possible to realize and provide a large capacity and low loss reactor device and transformer device.

DESCRIPTION OF SYMBOLS 1a, 1b, 31 York iron core 1c Toroidal core 1d Thin strip | belt-shaped magnetic body 2 Coil 2a Primary coil 2b Secondary coil 3, 30 Magnetic leg iron core 3a Slit 4 Isotropic magnetic body 5, 32 Gap adjustment means 6 Fixing jig 7 Base 8a 8b Fixing means 9 Cooling means 11 Rectifier circuit 12 Inverter circuit 13 AC power supply 14 Load 15 Chopper circuit 16 Battery 17, 25 Switching element, IGBT
18 Bypass circuit 19 Bypass converter circuit 20, 26 Reactor, reactor device 21 Capacitor 22 Smoothing capacitor 23 AC / DC conversion circuit (bridge circuit)
24 filter circuit 27 DC / AC conversion circuit (bridge circuit)

Claims (20)

Two opposing yoke cores,
A plurality of magnetic leg iron cores provided with gap adjusting means,
With
The two opposing yoke iron cores are connected by the plurality of magnetic leg iron cores, and at least one of the connecting portions has an isotropic magnetic body made of an isotropic magnetic material. In the reactor according to claim 1,
The reactor is characterized in that the isotropic magnetic body is composed of a powder magnetic core whose main component is a magnetic metal, or a sintered magnetic core such as ferrite. In the reactor according to claim 1,
The isotropic magnetic body has a substantially thin plate shape, and a cross-sectional shape in a direction parallel to a contact surface of the isotropic magnetic body with the magnetic leg iron core is substantially the same as a cross-sectional shape of the magnetic leg iron core. Reactor characterized by. In the reactor according to claim 1,
The reactor in which the plurality of magnetic leg iron cores are arranged on a substantially circumference with a predetermined angle. In the reactor according to claim 1,
The yoke iron core is constituted by winding a ribbon-shaped magnetic material in a substantially toroidal shape. In the reactor according to claim 1,
The plurality of magnetic leg iron cores are formed by winding a ribbon-shaped magnetic material into a substantially cylindrical shape, and at least one slit is provided in a longitudinal direction of the cylinder. In the reactor according to claim 3,
The thickness of the substantially thin plate-shaped isotropic magnetic body is 0.29 times or more the diameter of a cross section in a direction parallel to the contact surface of the isotropic magnetic body with the magnetic leg iron core. . In the reactor according to claim 1,
The plurality of magnetic leg iron cores have a substantially rectangular parallelepiped shape in which a plurality of thin ribbon magnetic materials are laminated. In the reactor according to claim 1,
The plurality of magnetic leg iron cores have a substantially fan shape having a predetermined apex angle obtained by winding a strip-shaped magnetic material in a toroidal shape and cutting the toroidal radial direction. In the reactor according to claim 1,
The reactor, wherein the plurality of magnetic leg iron cores and the two yoke iron cores are each formed by laminating a ribbon-shaped magnetic material, and the laminating directions are the same. In the reactor according to claim 1,
The said coil is comprised by the linear conductor provided with the insulating member, or the plate-shaped conductor, The reactor characterized by the above-mentioned.   The reactor according to claim 1 is connected to a bridge circuit composed of semiconductor elements together with a capacitor to form a filter circuit, and the filter circuit removes harmonic current components generated from the bridge circuit. A reactor characterized by having a function. Two opposing yoke cores,
A plurality of magnetic leg iron cores wound with coils,
With
The two opposing yoke iron cores are connected by the plurality of magnetic leg iron cores, and at least one of the connecting portions has an isotropic magnetic body made of an isotropic magnetic material. In the transformer according to claim 1,
The transformer is characterized in that the isotropic magnetic body is composed of a powder magnetic core whose main component is a magnetic metal, or a sintered magnetic core such as ferrite. The transformer according to claim 14, wherein
The transformer, wherein the plurality of magnetic leg iron cores are arranged on a substantially circumference with a predetermined angle. The transformer according to claim 14, wherein
The yoke iron core is constituted by winding a ribbon-shaped magnetic material in a substantially toroidal shape. The transformer according to claim 14, wherein
The plurality of magnetic leg iron cores are formed by winding a ribbon-shaped magnetic material into a substantially cylindrical shape, and at least one slit is provided in the longitudinal direction of the cylinder.   The transformer according to claim 14 is characterized in that the yoke iron core is crimped and fixed from above and below by a fixing jig, and a cooling means is provided on the concentric shaft of the yoke iron core.   A power converter comprising the reactor according to any one of claims 1 to 12.   A power converter comprising the transformer according to any one of claims 13 to 18.

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