JP7300942B2 - electromagnetic device - Google Patents

Description

The present invention relates to electromagnetic devices.

Conventionally, a coil component, which is an electromagnetic device of this kind, has been disclosed. This coil component has a first magnetic core around which a first coil is wound and a second magnetic core around which a second coil is wound. The narrow magnetic path portion, which has a smaller cross-sectional area, is sandwiched between the open magnetic path portions of the second magnetic core. According to this coil component, by energizing the second coil in the second magnetic core, which is the control core, main magnetic flux is generated in the first magnetic core, which is the main core, by energizing the first coil. A control magnetic flux is injected into the narrow magnetic path portion of the first magnetic core so as to be orthogonal. At this time, the inductance of the first coil can be changed by changing the value of the current supplied to the second coil to change the magnetic resistance of the first magnetic core.

JP 2010-93083 A

By the way, in designing the above coil component, in order to improve the controllability, there is a demand to expand the variable range of the magnetic resistance of the first magnetic core when the current value of the second coil is changed. be. In response to this request, the control magnetic flux is injected into the first magnetic core by closely contacting the open magnetic path portion of the second magnetic core with the narrow magnetic path portion of the first magnetic core without any gap. It is effective to increase the magnetic flux density in the narrow magnetic path portion.

However, in a structure in which the narrow magnetic path portion of the first magnetic core is sandwiched between the open magnetic path portions of the second magnetic core, as in this coil component, the open magnetic path portion is brought into close contact with the narrow magnetic path portion. Therefore, it is preferable to press-fit the second magnetic core.

Therefore, in this coil component, due to its structure, it is necessary to provide a gap between the narrow magnetic path portion and the open magnetic path portion. It is difficult to increase the magnetic flux density of the magnetic path. At this time, since the magnetic resistance of the path through which the control magnetic flux flows increases, the control magnetic flux generated even if the control current of the same value is energized becomes small, resulting in a problem of degraded controllability. Moreover, such a problem can occur not only in the coil components described above but also in electromagnetic devices such as variable transformers.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnetic device capable of increasing the magnetic flux density at a portion where the control magnetic flux is injected from the control core to the main core.

One aspect of the present invention is
A first magnetic leg (21) around which the main winding (11) is wound, and a second magnetic leg (22) extending in the same direction as the first magnetic leg across a first space (20a). ) and a primary core (20) having
A base portion (31) around which a control winding (12) is wound and provided with a second space (30a) with respect to the second magnetic leg portion of the main core, and a base portion (31) extending from the base portion. a control core (30) having a joint (32) closely joined to the second magnetic leg of the main core;
with
The width dimension (L2) of the second magnetic leg portion of the main core in the width direction (Y) perpendicular to the height direction (X) in which the first magnetic leg portion extends is the width of the first magnetic leg portion. It is configured to exceed the width dimension (L1) in the direction,
A magnetic circuit (C1, C3) in which the magnetic flux (Ma, Ma1, Ma2) flows through the first magnetic leg portion and the second magnetic leg portion of the main core in the height direction by energizing the main winding is formed. When the control winding is energized, the control magnetic flux (Mb) passes through the base portion and the joint portion of the control core and the second magnetic leg portion of the main core and crosses the magnetic circuit to the second magnetic field. an electromagnetic device (10, 110) configured to form a magnetic circuit (C2) flowing through two magnetic legs in the width direction;
It is in.

In the electromagnetic device of the above aspect, the main core has a first magnetic leg and a second magnetic leg, and the control core has a base and a junction. A main winding is wound around the first magnetic leg of the main core. The second magnetic leg portion of the main core extends along the first magnetic leg portion and has a predetermined width dimension greater than the width dimension of the first magnetic leg portion in the same direction. A control winding is wound around the base of the control core. The joint of the control core is closely joined to the second magnetic leg of the main core. When the main winding is energized, magnetic flux flows through one of the magnetic circuits passing through the first magnetic leg portion and the second magnetic leg portion of the main core. Also, when the control winding is energized, the control magnetic flux flows through the other magnetic circuit passing through the control core and the main core.

Here, the other magnetic circuit passes through the base portion and joint portion of the control core and the second magnetic leg portion of the main core, and the second magnetic leg portion is wider than the first magnetic leg portion. This is a circuit that flows in the width direction. Therefore, by energizing the control winding in the control core, the control magnetic flux is injected into the second magnetic leg of the main core so as to be orthogonal to the magnetic flux created in the main core by energizing the main winding. When the joint portion of the control core is in close contact with the second magnetic leg portion of the main core without a gap, the control magnetic flux injected into the second magnetic leg portion travels straight evenly over a wide range in the width direction of the second magnetic leg portion. can be made This increases the magnetic flux density of the second magnetic leg of the main core.

As described above, according to the above aspect, it is possible to provide an electromagnetic device capable of increasing the magnetic flux density at the portion where the control magnetic flux is injected from the control core to the main core.

It should be noted that the symbols in parentheses described in the claims and the means for solving the problems indicate the corresponding relationship with the specific means described in the embodiments described later, and limit the technical scope of the present invention. not a thing

1 is a schematic diagram of a power receiving device according to the first embodiment; FIG. 1 is a perspective view showing the configuration of a variable reactor that is the electromagnetic device of Embodiment 1. FIG. FIG. 3 is a plan view of the variable reactor of FIG. 2; FIG. 3 is a side view of the variable reactor of FIG. 2; FIG. 3 is an exploded perspective view of the core structure in FIG. 2; 4 is a plan view of a modification of the variable reactor of Embodiment 1. FIG. FIG. 7 is an exploded perspective view of the core structure in FIG. 6; FIG. 2 is a circuit diagram of a DC-DC converter according to a second embodiment; 4 is a perspective view showing the configuration of a variable transformer, which is an electromagnetic device of Embodiment 2. FIG. FIG. 10 is a plan view of the variable transformer of FIG. 9; FIG. 10 is a side view of the variable transformer of FIG. 9; FIG. 10 is an exploded perspective view of the core structure in FIG. 9; FIG. 10 is a perspective view of a core structure according to the first reference example of the variable transformer of Embodiment 2; FIG. 11 is a perspective view of a core structure according to a first modification of the variable transformer of Embodiment 2; FIG. 8 is a perspective view of a core structure according to a second modification of the variable transformer of Embodiment 2; FIG. 8 is a perspective view of a core structure according to a second reference example of the variable transformer of Embodiment 2; FIG. 8 is a perspective view of a core structure according to a third modification of the variable transformer of Embodiment 2; FIG. 11 is a perspective view of a core structure according to a third reference example of the variable transformer of Embodiment 2; FIG. 11 is a perspective view of a core structure according to a fourth modification of the variable transformer of Embodiment 2;

Hereinafter, embodiments of a variable reactor and a variable transformer as electromagnetic devices will be described with reference to the drawings.

In the drawings for describing the embodiments, unless otherwise specified, an arrow X indicates a first direction in which the winding axis of the main winding extends, and an arrow X indicates a second direction in which the winding axis of the control winding extends. Let arrow Y indicate a third direction perpendicular to both the first direction and the second direction indicated by arrow Z. Further, the first direction X referred to here is also called the height direction of each of the main core and the control core, and the second direction Y is also called the width direction of each of the main core and the control core.

(Embodiment 1)
As shown in FIG. 1, a power receiving device 1 according to the first embodiment is mounted on a vehicle. This power receiving device 1 includes a power factor compensation circuit 3 electrically connected to a power receiving coil 2, a variable inductor 4 that changes impedance Z, a filter 5 that removes noise from an induced alternating current, and a filter 5. A rectifier circuit 6 that converts AC current from which noise has been removed into a DC current, a converter 7 that boosts the power converted by the rectifier circuit 6, and a battery B that stores the power supplied from the converter 7. there is

Variable reactor 10 of the first embodiment is an electromagnetic device provided in converter 7 of power receiving device 1 . As shown in FIGS. 2 to 4, the variable reactor 10 has a variable inductance of the main winding 11 by changing the magnetic resistance of the main core 20 by controlling the energizing current in the control winding 12. It is configured as a variable reactor.

The variable reactor 10 has a core structure in which a main core 20 and a control core 30 are joined together. Both the main core 20 and the control core 30, which constitute the core structure, are made of a magnetically permeable material.

Control core 30 is preferably made of a material having a higher relative magnetic permeability than main core 20 . Also, the control core 30 is preferably made of a material having a saturation magnetic flux density higher than that of the main core 20 .

The term "relative magnetic permeability" as used herein refers to the ratio of the magnetic permeability of an object to the magnetic permeability of a vacuum. Permeability is derived by multiplying the magnetic flux density in the magnetic field and the magnetic field strength. The higher the relative permeability, the easier it is for magnetic flux to pass through, and the lower the relative permeability, the harder it is for magnetic flux to pass through.

The term "saturation magnetic flux density" as used herein refers to the limit value of the magnetic flux density when a ferromagnetic material is magnetized by applying a magnetic field. The higher the saturation magnetic flux density, the stronger the magnetism, and the lower the saturation magnetic flux density, the weaker the magnetism.

As the material of the main core 20, typically ferrite, which is a magnetic material whose main component is iron oxide, can be used. As a material for the control core 30, typically, permalloy (PB permalloy, PC permalloy, etc.), which is a soft magnetic material containing nickel, can be used.

The main core 20 has a first magnetic leg portion 21 , a second magnetic leg portion 22 , and two connecting portions 21 a that connect the first magnetic leg portion 21 to the second magnetic leg portion 22 . The main core 20 is configured such that the height dimension in the first direction X is constant. In the main core 20, the first magnetic leg portion 21 is arranged substantially in the center of the second magnetic leg portion 22 in the second direction Y, so that the main core 20 has a substantially T shape when viewed from the first direction X. (see FIG. 3). This configuration is defined as "the main core 30 is such that the imaginary center line of the first magnetic leg portion 21 in the second direction Y forms a space 30a between a first joint portion 32A and a second joint portion 32B of the control core 30, which will be described later. It is configured so that it can pass through." can also be said.

The first magnetic leg portion 21 is a portion of the main core 20 extending in the first direction X, and the main winding 11, which is the main coil, is wound around the winding axis A1 on the first magnetic leg portion 21. ing. This main winding 11 is also called a "reactor winding".

The second magnetic leg portion 22 is a portion of the main core 20 that extends in the same first direction as the first magnetic leg portion 21 across a space 20a serving as a first space. That is, the first magnetic leg portion 21 and the second magnetic leg portion 22 extend parallel to each other with the space 20a interposed therebetween. The second magnetic leg portion 22 has a rectangular facing surface 22a facing the control core 30 on the side opposite to the first magnetic leg portion. The facing surface 22a is formed on a plane defined by the first direction X and the second direction Y. As shown in FIG.

The two connecting portions 21a extend parallel to each other in a third direction Z orthogonal to the first direction X with the space 20a interposed therebetween. As a result, the shape of the main core 20 when viewed from the second direction Y has a substantially rectangular annular shape (see FIG. 4).

The control core 30 has a base 31 and a joint 32 . The base portion 31 is a portion provided with a space 30a as a second space from the second magnetic leg portion 22 of the main core 20, and extends in the second direction Y. As shown in FIG. A control winding 12, which is a control coil, is wound around the winding axis A2 in this base portion 31. As shown in FIG. As for the winding axis A2 of the control winding 12, the main winding 11 is perpendicular to the winding axis A1. The control core 30 has a constant first-direction X height dimension H (see FIG. 4) and is configured to have the same height as the main core 20 .

The joint portions 32 are portions extending from two portions of the base portion 31 and joined to the second magnetic leg portions 22 of the main core 20 in close contact with each other. Specifically, the joint portion 32 is configured by a first joint portion 32A and a second joint portion 32B extending from both end sides of the base portion 31 in the second direction Y with a space 30a therebetween. Further, the first joint portion 32A and the second joint portion 32B are closely joined to the facing surface 22a of the second magnetic leg portion 22 of the main core 20 at the tip surface 32a thereof.

As a result, the shape of the control core 30 when viewed from the first direction X is substantially C-shaped or substantially U-shaped annular. The shape when viewed from the first direction X is a substantially rectangular ring (see FIG. 3).

As shown in FIG. 2, with respect to the main core 20, when the second direction Y perpendicular to the first direction X, which is the direction in which the first magnetic leg 21 extends, is taken as the width direction, the second magnetic leg 22 is The width dimension L2 in the second direction Y is configured to exceed the width dimension L1 in the second direction Y of the first magnetic leg portion 21 . In other words, the second magnetic leg portion 22 has an expanded width structure in which the width in the second direction Y is expanded compared to the first magnetic leg portion 21 . Further, the second magnetic leg portion 22 is configured such that its width dimension L2 is approximately the same as the width dimension of the control core 30 in the two directions Y. As shown in FIG.

Since the second direction Y substantially coincides with the direction in which the winding axis A2 extends, the width dimension L1 of the first magnetic leg portion 21 is referred to as the dimension of the first magnetic leg portion 21 in the direction in which the winding axis A2 extends. The width dimension L2 of the second magnetic leg portion 22 can also be said to be the dimension of the second magnetic leg portion 22 in the direction in which the winding axis A2 extends.

In the variable reactor 10 described above, when the main winding 11 is energized, the main magnetic flux Ma flows through the first magnetic leg portion 21 and the second magnetic leg portion 22 of the main core 20 in the first direction X in the annular first magnetic circuit. C1 is formed.

On the other hand, when the control winding 12 is energized, the control magnetic flux Mb passes through the base portion 31 and the joint portion 32 of the control core 30 and the second magnetic leg portion 22 of the main core 20 and crosses the first magnetic circuit C1. Thus, an annular second magnetic circuit C2 flowing in the second direction Y through the second magnetic leg portion 22 is formed. At this time, since the first magnetic leg portion 21 is arranged substantially in the center between both ends of the second magnetic leg portion 22 of the main core 20 in the second direction Y, the control magnetic flux Mb flowing through the second magnetic circuit C2 is 1 It becomes easier to cross the main magnetic flux Ma flowing through the magnetic circuit C1.

The method of joining the second magnetic leg portion 22 of the main core 20 and the joining portion 32 of the control core 30 is not particularly limited. Then, the two joint portions 32A and 32B of the control core 30 are brought close to the facing surface 22a of the second magnetic leg portion 22 of the main core 20, and the tip surfaces 32a of the two joint portions 32A and 32B are brought into contact with the second magnetic leg portion. A method of bonding to the facing surface 22a of the portion 22 can be used.

According to the first embodiment described above, the following operational effects are obtained.

In the variable reactor 10 described above, the main core 20 has a first magnetic leg portion 21 and a second magnetic leg portion 22 , and the control core 30 has a base portion 31 and a joint portion 32 . A main winding 11 is wound around the first magnetic leg portion 21 of the main core 20 . The second magnetic leg portion 22 of the main core 20 extends along the first magnetic leg portion 21, and the width dimension L2 in the second direction Y, which is the predetermined width direction, is the same direction as the first magnetic leg portion 21. exceeds the width dimension L1 of A control winding 12 is wound around the base 31 of the control core 30 . The joint portion 32 of the control core 30 is closely joined to the second magnetic leg portion 22 of the main core 20 .

When the main winding 11 is energized, the main magnetic flux Ma flows through the first magnetic circuit C1 passing through the first magnetic leg portion 21 and the second magnetic leg portion 22 of the main core 20 . Also, the control magnetic flux Mb flows through the second magnetic circuit C2 by energizing the control winding 12 .

Here, the second magnetic circuit C2 passes through the base portion 31 and the joint portion 32 of the control core 30 and the second magnetic leg portion 22 of the main core 20, and is in the second direction Y relative to the first magnetic leg portion 21. It is a circuit that flows in the second direction Y through the second magnetic leg portion 22 whose width dimension is expanded.

Therefore, by energizing the control winding 12 in the control core 30, the second magnetic leg 22 of the main core 20 is controlled so as to be perpendicular to the main magnetic flux Ma generated in the main core 20 by energizing the main winding 11. Although the magnetic flux Mb is injected, since the joint 32 of the control core 30 is in close contact with the facing surface 22a of the second magnetic leg 22 of the main core 20 at this time, the magnetic flux Mb is injected into the second magnetic leg 22. The control magnetic flux Mb can be caused to travel straight evenly over a wide range in the second direction Y, which is the width direction of the second magnetic leg portion 22 .

This increases the magnetic flux density Mb of the second magnetic leg portion 22 of the main core 20 . As a result, the controllability of the main magnetic flux Ma generated in the main core 20 by energizing the main winding 11 is improved, and the inductance of the main winding 11 can be changed with a smaller current.

Therefore, according to Embodiment 1 described above, it is possible to provide the variable reactor 10 capable of increasing the magnetic flux density of the second magnetic leg portion 22 , which is the portion where the control magnetic flux Mb is injected from the control core 30 to the main core 20 .

According to the variable reactor 10 described above, the joint portion 32 of the control core 30 can be joined to the second magnetic leg portion 22 of the main core 20 without being press-fitted. In this case, since a press-fitting structure is not used, problems such as cracks that may occur during press-fitting can be prevented.

According to the variable reactor 10 described above, the structure of the control core 30 can be simplified by configuring the joint portion 32 of the control core 30 with the first joint portion 32A and the second joint portion 32B. Further, the first joint portion 32A and the second joint portion 32B extend parallel to each other, and the first joint portion 32A and the second joint portion 32B are joined by joining the respective tip end surfaces 32a to the opposing surfaces 22a of the second magnetic leg portions 22 of the main core 20. This is effective in increasing the adhesion between the second magnetic leg portion 22 and the portion 32A and the second joint portion 32B.

According to the variable reactor 10 described above, by using a material having a higher relative magnetic permeability than that of the main core 20 for the control core 30, a larger control magnetic flux can be generated with a smaller current. Therefore, the controllability of the magnetic resistance of the main core 20 can be improved. In the present embodiment, the width dimension L2 of the second magnetic leg portion 22 in the second direction Y is longer than that of the first magnetic leg portion 21 of the main core 20. Therefore, the relative magnetic permeability of the control core 30 is set to Even if the magnetic flux is increased exponentially, it is possible to prevent the control magnetic flux Mb generated in the control core 30 from becoming difficult to flow through the second magnetic leg portion 22 of the main core 20 .

According to the variable reactor 10 described above, a larger magnetic flux can be injected from the control core 30 to the main core 20 by using a material having a saturation magnetic flux density higher than that of the main core 20 for the control core 30 . Thereby, the variable range of the magnetic resistance in the main core 20 can be further expanded, and the controllability can be improved. On the other hand, since the cross-sectional area of the control core 30 with the higher saturation magnetic flux density can be reduced, the size of the core structure consisting of the main core 20 and the control core 30 can be reduced.

As a modification particularly related to the first embodiment described above, a core structure that replaces the core structure of the variable reactor 10 can be employed.

As shown in FIG. 6, in the core structure of the variable reactor 10A according to this modification, the main core 20 has a substantially L shape when viewed from the first direction X, and the control core 30 is The shape when viewed from the first direction X is substantially C-shaped. At this time, as in the case of the variable reactor 10 , the second magnetic leg portion 22 is configured such that its width dimension L 2 exceeds the width dimension L 1 of the first magnetic leg portion 21 . On the other hand, the second magnetic leg portion 22 is configured such that its width dimension L2 is smaller than the width dimension in the second direction Y of the control core 30 .

As shown in FIGS. 6 and 7, the control core 30 has a first joint portion 32A whose front end surface 32a is joined to the opposing surface 22a of the second magnetic leg portion 22 of the main core 20, and a second joint portion 32B. The tip surface 32 a is configured to be joined to the side surface 22 b of the second magnetic leg portion 22 of the main core 20 . The side surface 22b is a surface perpendicular to the opposing surface 22a and formed on a plane defined by the first direction X and the third direction Z. As shown in FIG.

When this core structure is viewed in the first direction X, a portion extending linearly in the second direction Y by the second magnetic leg portion 22 of the main core 20 and a portion on the tip side of the second joint portion 32B of the control core 30 is formed, and the first magnetic leg portion 21 of the main core 20 is arranged approximately in the center between both ends of this portion in the second direction Y. As shown in FIG. This arrangement makes it easier for the control magnetic flux Mb flowing through the second magnetic circuit C2 to cross the main magnetic flux Ma flowing through the first magnetic circuit C1.

It should be noted that it is also possible to change so that the tip end surface 32a of the second joint portion 32B is joined to the facing surface 22a of the second magnetic leg portion 22 of the main core 20 as necessary.

Other configurations are the same as those of the variable reactor 10 of the first embodiment.

According to this variable reactor 10A, a core structure having a shape different from that of the variable reactor 10 can be provided.

In addition, the same effects as the variable reactor 10 of the first embodiment are obtained.

Other embodiments related to the first embodiment described above will be described below with reference to the drawings. In other embodiments, the same reference numerals are assigned to the same elements as those of the first embodiment described above, and the description of the same elements will be omitted.

(Embodiment 2)
As shown in the circuit diagram of FIG. 8, the DC-DC converter 101 according to the second embodiment is a full-bridge converter, and has a function of converting direct current to high-frequency alternating current and then converting the alternating current back to direct current. have.

This DC-DC converter 101 includes a plurality of switching elements 102 connected to a DC power source B, diodes 103 and 104, a reactor 105, an electrolytic capacitor 106, and a variable transformer 110 as an electromagnetic device. there is

The variable transformer 110 of Embodiment 2 is configured to vary the transformation ratio, which is the ratio of the primary voltage to the secondary voltage. According to this variable transformer 110, the step-down ratio is increased when the input voltage is relatively high, and the step-down ratio is decreased when the input voltage is relatively low, thereby expanding the input voltage range. In addition, according to this variable transformer 110, the duty (on time width) of the PWM control of the plurality of switching elements 102 can be fixed, and the output power can be controlled by the transformation ratio, thereby reducing noise and loss. can be fixed at an effective duty.

As shown in FIGS. 9 to 11, variable transformer 110 has a core structure in which main core 20 and control core 30 are joined together, like variable reactor 10 of the first embodiment.

The main core 20 includes a first magnetic leg portion 21, a second magnetic leg portion 22, a third magnetic leg portion 23, and two connecting portions 21a that connect the first magnetic leg portion 21 to the second magnetic leg portion 22. and two connection portions 21 b that connect the first magnetic leg portion 21 to the third magnetic leg portion 23 . The main core 20 is configured such that the height dimension in the first direction X is constant. The main core 20 has a substantially T shape when viewed from the first direction X (see FIG. 10).

The second magnetic leg portion 22 is a portion provided along the first magnetic leg portion 21 across the first magnetic leg portion 21 on the side opposite to the second magnetic leg portion 22 with a space 20b therebetween. That is, the first magnetic leg portion 21 and the third magnetic leg portion 23 extend parallel to each other with the space 20b interposed therebetween. Further, as in the case of the variable reactor 10 of Embodiment 1, the width dimension L2 of the second magnetic leg portion 22 is configured to exceed the width dimension L1 of the first magnetic leg portion 21 (see FIG. 10). ).

The two connecting portions 21a extend parallel to each other in the third direction Z across the space 20a, and the two connecting portions 21b extend parallel to each other in the third direction Z across the space 20b. As a result, when the main core 20 is viewed from the second direction Y, the first magnetic leg portion 21, the second magnetic leg portion 22, and the two connecting portions 21a form a substantially rectangular annular shape. The portion 21, the third magnetic leg portion 23, and the two connecting portions 21b form another substantially rectangular annular shape (see FIG. 11).

In the main core 20, the primary winding 11A as the main winding is wound around the first magnetic leg portion 21, and the secondary winding 11B corresponding to the primary winding 11A is wound around the third magnetic leg portion 23. there is

In the variable transformer 110 described above, when the primary winding 11A is energized, the magnetic flux Ma2 as the interlinking magnetic flux flows through the first magnetic circuit C1 formed by the first magnetic leg portion 21 and the third magnetic leg portion 23, A leakage magnetic flux Ma1 flows through the third magnetic circuit C3 formed by the first magnetic leg portion 21 and the second magnetic leg portion 22 .

By changing the magnetic resistance of the main core 20 by controlling the energized current in the control winding 12, the leakage magnetic flux Ma1 increases or decreases, thereby controlling the interlinkage magnetic flux Ma2, thereby causing the voltage of the secondary winding 11B to continuously increase. is set to be variable.

As shown in FIG. 12, in the core structure of the variable transformer 110 as well, similar to the core structure of the variable reactor 10 of the first embodiment, the surface 22a facing the second magnetic leg 22 of the main core 20 is controlled. It is preferable to use a method in which the two joint portions 32A and 32B of the core 30 are brought close to each other and the tip surfaces 32a of the two joint portions 32A and 32B are joined to the opposing surface 22a of the second magnetic leg portion 22.

Other configurations are the same as those of the first embodiment.

According to the variable transformer 110 of the second embodiment, the joint portion 32 of the control core 30 is brought into close contact with the opposing surface 22a of the second magnetic leg portion 22 of the main core 20, so that the second magnetic leg portion of the main core 20 is The magnetic flux density Mb of the portion 22 increases. As a result, the controllability of the leakage magnetic flux Ma1 generated in the main core 20 by energization of the primary winding 11A is improved, and the controllability of the interlinkage magnetic flux Ma2 is improved, so that the transformation ratio can be changed with a smaller current. be possible.

Therefore, according to the second embodiment described above, it is possible to provide the variable transformer 110 capable of increasing the magnetic flux density of the second magnetic leg portion 22, which is the portion where the control magnetic flux Mb is injected from the control core 30 to the main core 20. .

In addition, the same effects as those of the first embodiment are obtained.

As a modified example particularly related to the above-described second embodiment, a core structure that replaces the above-described core structure of the variable transformer 110 can be adopted. Except for the core structure, it is the same as the variable transformer 110 .

Modified examples and reference examples of the core structure of the variable transformer 110 will be described below with reference to FIGS. 13 to 19. FIG.

(First reference example)
As shown in FIG. 13, the core structure of the variable transformer 110A according to the first reference example is such that the shape of the second magnetic leg portion 22 of the main core 20 and the shape of the control core 30 are different from those of the variable transformer 110. It differs from that of the core structure.

That is, the second magnetic leg portion 22 has protrusions 221 that partially protrude from the central region in the first direction X to both sides in the second direction Y. As shown in FIG. A facing surface 221 a of each projecting portion 221 that faces the control core 30 constitutes a part of the facing surface 22 a of the second magnetic leg portion 22 . Also, the control core 30 is configured such that its dimension in the first direction X is smaller than the dimension in the first direction X of the second magnetic leg portion 22 .

In this core structure, the tip surfaces 32a of the first joint portion 31A and the second joint portion 32B are joined to the two opposing surfaces 221a of the second magnetic leg portion 22, respectively. Further, in this core structure, the width dimension L2 in the second direction Y of the two projecting portions 221 of the second magnetic leg portion 22 is substantially the same as the width dimension in the second direction Y of the control core 30, and It is configured to exceed the width dimension L1 in the second direction Y of the first magnetic leg portion 21 . Since the two protruding portions 221 are part of the second magnetic leg portion 22, this configuration is also similar to the case of the variable transformer 110. exceeds the width dimension L1 of the portion 21.".

Other configurations are similar to those of the core structure of variable transformer 110 .

According to the variable transformer 110A, similarly to the variable transformer 110, the joint portion 32 of the control core 30 can be closely attached to the facing surface 221a of the second magnetic leg portion 22 of the main core 20 without any gap.

In addition, the same effects as when using the variable transformer 110 are obtained.

A feature of the core structure of the variable transformer 110A is that a part of the second magnetic leg portion 22 of the main core 20 protrudes in the second direction Y; The points can also be applied to the core structure of the variable reactor 10 of the first embodiment.

( First modified example)
As shown in FIG. 14, the core structure of the variable transformer 110B according to the first modified example differs from the core structure of the variable transformer 110 in the shape of the second magnetic leg portion 22 of the main core 20. ing.

That is, the second magnetic leg portion 22 has a rear surface 22c on the side opposite to the facing surface 22a in the third direction Z, and the upper and lower regions of the rear surface 22c in the first direction X to the first magnetic leg portion 21. It has a projecting portion 222 projecting so as to extend. This protruding structure can also be said that "the two connecting portions 21a protrude to both sides in the second direction Y until they are flush with the second magnetic leg portion 22." Thereby, the dimension of the second magnetic leg portion 22 in the third direction Z is enlarged as compared with the core structure of the variable transformer 110 .

Other configurations are similar to those of the core structure of variable transformer 110 .

According to the variable transformer 110B, similarly to the variable transformer 110, the joint portion 32 of the control core 30 can be closely attached to the facing surface 22a of the second magnetic leg portion 22 of the main core 20 without any gap.
According to this variable transformer 110B, by providing the projection 222 on the second magnetic leg 22, the variable range of the magnetic resistance of the main core 20 can be further expanded, and the variable range of the transformation ratio can be expanded. can be done.

In addition, the same effects as when using the variable transformer 110 are obtained.

A feature of the core structure of the variable transformer 110B is that a part of the second magnetic leg portion 22 of the main core 20 protrudes in the third direction Z; The points can also be applied to the core structure of the variable reactor 10 of the first embodiment. In the case of the variable reactor 10, the variable range of the magnetic resistance of the main core 20 can be further expanded, and the variable range of the inductance of the main winding 11 can be expanded.

( Second modified example)
As shown in FIG. 15, the core structure of variable transformer 110C according to the second modification differs from that of variable transformer 110 in the configuration of main core 20 and control core 30 .

That is, in this core structure, a gap G as a gap in the first direction X is provided in each of the first magnetic leg portion 21, the second magnetic leg portion 22, and the third magnetic leg portion 23 of the main core 20. . Similarly, a gap G in the first direction X is provided in the control core 30 . An insulating sheet 40 made of an electrical insulating material such as resin is interposed in the gap G. As shown in FIG. This gap G may be an air gap.

Other configurations are similar to those of the core structure of variable transformer 110 .

According to this variable transformer 110C, by providing the gap G between the main core 20 and the control core 30, it becomes possible to adjust the excitation inductance, mutual inductance, and leakage inductance, and to increase the maximum magnetic flux density of the main core 20. It is effective in preventing the magnetic saturation state from exceeding.

In addition, the same effects as when using the variable transformer 110 are obtained.

In the main core 20 , a gap G can be provided in at least one of the first magnetic leg portion 21 , the second magnetic leg portion 22 and the third magnetic leg portion 23 . Only when the gap G is provided in the second magnetic leg portion 22, it is necessary to provide the gap G in the control core 30 joined to the second magnetic leg portion 22 as well. Thereby, it is possible to prevent the effect of providing the gap G in the second magnetic leg portion 22 from significantly deteriorating.

A feature of the core structure of this variable transformer 110C is that a gap G is provided between the main core 20 and the control core 30. can also be applied to the core structure of In the case of the variable reactor 10, by providing a gap G in at least one of the first magnetic leg portion 21 and the second magnetic leg portion 22, it becomes possible to adjust the inductance of the main winding 11, and the main core It is effective in preventing magnetic saturation beyond the maximum magnetic flux density of 20.

( Second reference example)
As shown in FIG. 16, the core structure of the variable transformer 110D according to the second reference example includes the core structure of the variable transformer 110A (see FIG. 13) and the core structure of the variable transformer 110C (see FIG. 15). reference) is applied.

That is, in this core structure, a gap G as a gap in the first direction X is provided in each of the first magnetic leg portion 21 and the second magnetic leg portion 22 of the main core 20 .

Other configurations are the same as those of the core structure of the variable transformer 110A.

According to the variable transformer 110D, the joint portion 32 of the control core 30 can be closely attached to the facing surface 221a of the second magnetic leg portion 22 of the main core 20 without any gap.
According to this variable transformer 110D, it is possible to adjust the excitation inductance, mutual inductance, and leakage inductance, and it is effective in preventing the magnetic flux density exceeding the maximum magnetic flux density of the main core 20 and magnetic saturation. .

In addition, the same effects as when using the variable transformer 110 are obtained.

( Third modified example)
As shown in FIG. 17, the core structure of the variable transformer 110E according to the third modification is the core structure of the variable transformer 110B (see FIG. 14) and the core structure of the variable transformer 110C (see FIG. 15). reference) is applied.

That is, in this core structure, the first magnetic leg portion 21 and the second magnetic leg portion 22 of the main core 20 are each provided with a gap G as a gap in the first direction X, and the control core 30 is provided with a gap G as a gap in the first direction X. A gap G of X is provided.

Other configurations are similar to those of the core structure of variable transformer 110B.

According to the variable transformer 110E, the joint portion 32 of the control core 30 can be closely attached to the facing surface 22a of the second magnetic leg portion 22 of the main core 20 without any gap.
According to this variable transformer 110B, the variable range of the magnetic resistance of the main core 20 can be further expanded, and the variable range of the transformation ratio can be expanded.
According to this variable transformer 110B, the joint portion 32 of the control core 30 can be brought into close contact with the facing surface 221a of the second magnetic leg portion 22 of the main core 20 without any gap, and the excitation inductance, mutual inductance, and leakage inductance can be reduced. It is tunable and is effective in preventing the maximum magnetic flux density of the main core 20 from being exceeded and magnetic saturation.

In addition, the same effects as when using the variable transformer 110 are obtained.

( Third reference example)
As shown in FIG. 18, the core structure of the variable transformer 110F according to the third reference example includes the core structure of the variable transformer 110D (see FIG. 16) and the core structure of the variable transformer 110B (see FIG. 14). reference) is applied.

That is, in this core structure, the second magnetic leg portion 22 of the main core 20 includes the projecting portion 221 partially projecting from the central region in the first direction X to both sides in the second direction Y, and the second magnetic leg portion 221 of the projecting portion 221 . and a projecting portion 222 projecting from a lower region in the one direction X to the first magnetic leg portion 21 .

Other configurations are similar to those of the core structure of variable transformer 110D.

According to the variable transformer 110F, by providing the protrusion 222 on the second magnetic leg 22, the variable range of the magnetic resistance of the main core 20 can be further expanded, and the variable range of the transformation ratio can be expanded. can.

In addition, the same effects as when using the variable transformer 110 are obtained.

( Fourth modified example)
As shown in FIG. 19, the core structure of a variable transformer 110G according to the fourth modification is such that the number of magnetic legs of the main core 20 and the number of control cores 30 are the same as the core structure of the variable transformer 110. is different from that of

That is, main core 20 has four magnetic legs, which is more than the core structure of variable transformer 110 . The fourth magnetic leg portion 24 is a portion provided along the third magnetic leg portion 23 across the space 20c, and the control core 30 is joined to the fourth magnetic leg portion 24 as well. . The third magnetic leg portion 23 and the fourth magnetic leg portion 24 extend parallel to each other across the space 20b, and are connected via two connecting portions 21c extending parallel to each other in the third direction Z across the space 20c. connected to each other. The fourth magnetic leg portion 24 has the same shape as the second magnetic leg portion 22 . When viewed from the first direction X, the main core 20 has a substantially I shape.

Other configurations are similar to those of the core structure of variable transformer 110 .

According to the variable transformer 110G, compared with the core structure of the variable transformer 110, it is possible to provide a core structure in which the number of magnetic legs of the main core 20 and the number of control cores 30 are different. In this case, the number of magnetic leg portions of the main core 20 is not limited to four, and may be five or more as required. The number of control cores 30 is not limited to two, and may be three or more if necessary.

In addition, the same effects as when using the variable transformer 110 are obtained.

The present invention is not limited to the exemplary embodiments described above, and various applications and modifications are conceivable without departing from the scope of the present invention. For example, it is also possible to implement the following forms that apply the above-described embodiments.

In the above-described embodiment, the case where the two joints 32 extend from both ends of the base 31 of the control core 30 in the second direction Y is illustrated. Various structures can be adopted in which at least one of the two joint portions 32 extends from an arbitrary position between both ends of the base portion 31 in the second direction Y. .

In the above-described embodiment, the case where the leading end surfaces 32a of the two joint portions 32 of the control core 30 are joined to the second magnetic leg portion 22 of the main core 20 was exemplified, but instead of this, the control core 30 It is also possible to employ a structure in which at least one of the two joint portions 32 of 1 is joined to the second magnetic leg portion 22 of the main core 20 at a portion other than the tip surface 32a.

In the above-described embodiment, the case where the control core 30 is made of a material having a higher relative magnetic permeability than the main core 20 and a saturation magnetic flux density higher than that of the main core 20 was exemplified. The control core 30 is made of a material with a lower or the same relative magnetic permeability than the main core 20, and the control core 30 is made of a material with a smaller or the same saturation magnetic flux density than the main core 20. can also

In the above-described embodiment, for each of the variable reactor 10 and the variable transformer 110, the characteristics of the core structure having the main core 20 and the control core 30 were illustrated. It can also be applied to electromagnetic devices other than transformer 110 .

10 variable reactor (electromagnetic device)
11 main winding 11A primary winding (main winding)
11B secondary winding 12 control winding 20 main core 20a space 21 first magnetic leg 22 second magnetic leg 22a facing surface 23 third magnetic leg 30 control core 31 base 32 joint 32a tip surface 32A first joint Part 32B Second joint C1 First magnetic circuit (magnetic circuit)
C2 second magnetic circuit (magnetic circuit)
C3 Third magnetic circuit (magnetic circuit)
L1, L2 Width dimension Ma Main magnetic flux (magnetic flux)
Ma1 Leakage magnetic flux (magnetic flux)
Mb Control magnetic flux X First direction (direction in which the first magnetic leg extends)
Y second direction (width direction)
110 variable transformer (electromagnetic device)

Claims (7)

A first magnetic leg (21) around which the main winding (11) is wound, and a second magnetic leg (22) extending in the same direction as the first magnetic leg across a first space (20a). ) and a primary core (20) having
A base portion (31) around which a control winding (12) is wound and provided with a second space (30a) with respect to the second magnetic leg portion of the main core, and a base portion (31) extending from the base portion. a control core (30) having a joint (32) closely joined to the second magnetic leg of the main core;
with
The second magnetic leg portion of the main core has the same dimension in the height direction (X) in which the first magnetic leg portion extends as the dimension of each of the first magnetic leg portion and the control core; , the width dimension (L2) in the width direction (Y) perpendicular to the height direction is larger than the width dimension (L1) of the first magnetic leg portion in the width direction,
A magnetic circuit (C1, C3) in which the magnetic flux (Ma, Ma1, Ma2) flows through the first magnetic leg portion and the second magnetic leg portion of the main core in the height direction by energizing the main winding is formed. When the control winding is energized, the control magnetic flux (Mb) passes through the base portion and the joint portion of the control core and the second magnetic leg portion of the main core and crosses the magnetic circuit to the second magnetic field. An electromagnetic device (10, 110) configured to form a magnetic circuit (C2) flowing in the two magnetic legs in the width direction. The joint portion of the control core is constituted by a first joint portion (32A) and a second joint portion (32B) that extend apart from each other across the second space from both widthwise end sides of the base portion. 2. The electromagnetic device according to claim 1, wherein said first joint portion and said second joint portion are joined to said second magnetic leg portion at their distal end surfaces (32a). The first joint portion and the second joint portion extend parallel to each other, and the tip end surfaces of the first joint portion and the second joint portion are opposite surfaces of the second magnetic leg portion of the main core opposite to the first magnetic leg portion. 3. The electromagnetic device of claim 2, bonded to (22a). The electromagnetic device according to any one of claims 1 to 3, wherein said control core is made of a material having a higher relative magnetic permeability than said main core. The electromagnetic device according to any one of claims 1 to 3, wherein the control core is made of a material having a higher saturation magnetic flux density than the main core. A reactor winding as the main winding is wound around the first magnetic leg portion of the main core. The electromagnetic device according to any one of claims 1 to 5, which is configured as a variable reactor in which the inductance of the reactor winding is variable. The main core has a third magnetic leg (23) provided along the first magnetic leg on the side opposite to the second magnetic leg across the first magnetic leg, A primary winding (11A) as the main winding is wound around the first magnetic leg, and a secondary winding (11B) is wound around the third magnetic leg,
The electromagnetic device according to any one of claims 1 to 5, wherein the electromagnetic device is configured as a variable transformer in which the voltage of the secondary winding is made variable by controlling the energized current in the control winding.

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