JP2022144632A - Laminated core and transformer - Google Patents

Abstract

To provide a laminated core for a transformer capable of reducing iron loss more than before by a simple method.SOLUTION: A laminated core 1 includes a yoke portion 2, and a leg iron portion 4 arranged perpendicular to the yoke portion 2 and laminated with grain-oriented electrical steel sheets having a first magnetic orientation, and the yoke portion 2 includes a directional member having concave portions 7A and 7B laminated with a grain-oriented electrical steel sheet having a second magnetic orientation perpendicular to the first magnetic orientation and provided in a region including a part of the interface between the yoke portion 2 and the leg iron portion 4, and a non-directional member 8 on which non-oriented electrical steel sheets are laminated and which is fitted in the concave portions 7A and 7B of the directional member.SELECTED DRAWING: Figure 1

Description

The present invention relates to laminated cores and transformers.

2. Description of the Related Art Conventionally, in a transformer, an iron core including a yoke portion and a leg iron portion manufactured by laminating electromagnetic steel sheets is used. In order to improve iron loss characteristics in transformers, grain-oriented electrical steel sheets having good magnetization characteristics in the rolling direction are sometimes used as the electrical steel sheets.

A laminated core for a three-phase transformer comprises two yokes and three leg irons. Each of the two yoke parts and the three leg iron parts is constructed by laminating unidirectional magnetic steel sheets. This laminated core has a T-joint where a yoke and a central leg iron are joined vertically. Flux flows in complex paths in a T-junction. When the magnetic flux flowing out of the yoke flows into the central leg iron, the magnetic flux flowing along the rolling direction of the yoke flows into the leg iron near the T-shaped joint after passing the leg iron. A wraparound event of the magnetic flux occurs. Also, when magnetic flux flows in a path that circulates between two yoke parts and two outer leg iron parts, the magnetic flux once enters the central leg iron part and then returns to the yoke part. An event had occurred.

For example, in the laminated core disclosed in Patent Document 1, in order to suppress the penetration of the magnetic flux into the above-described central leg iron portion, the T-shaped joint portion of the yoke portion is provided with a rolling direction perpendicular to the rolling direction of the yoke portion. A V-shaped notch is formed with the width direction as the depth direction. Further, a segment composed of a material having vector magnetic properties obtained by applying continuous linear laser irradiation processing in two mutually intersecting directions in a grid pattern is fitted into the cut portion.

Japanese Unexamined Patent Application Publication No. 2020-9910

However, the technique according to Patent Literature 1 requires laser irradiation processing as described above for the iron core to be fitted into the notched portion, so there is a problem that the manufacturing process becomes complicated and the manufacturing cost increases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated core for a transformer capable of reducing iron loss more than conventionally by a simple method.

A laminated core according to an aspect of the present invention includes a yoke portion, and a leg iron portion which is arranged in a direction perpendicular to the yoke portion and in which grain-oriented electrical steel sheets having a first magnetic orientation are laminated. wherein the yoke portion is laminated with grain-oriented electrical steel sheets having a second magnetic directionality perpendicular to the first magnetic directionality, and an interface between the yoke portion and the leg iron portion A laminated core comprising: a directional member having a recess provided in a region including a part of the directional member;

Further, a transformer according to an aspect of the present invention is a transformer including the laminated core described above, and a primary coil and a secondary coil wound around the laminated core.

1 is a configuration diagram of a laminated core 1 according to an embodiment of the present invention; FIG. FIG. 4 is an explanatory diagram showing an example of a method for manufacturing the laminated core 1 according to one embodiment of the present invention; FIG. 4 is a diagram showing a simulation result of the shape of a path through which magnetic flux generated in the laminated core 1 according to one embodiment of the present invention flows; FIG. 5 is a diagram showing the configuration of a laminated core 50 as a comparative example and its iron loss density distribution; 1 is a diagram showing the configuration of a laminated core 1 and its iron loss density distribution according to an embodiment of the present invention; FIG. FIG. 5 is a diagram showing magnetic flux density measurement points in a laminated core 50 as a comparative example. FIG. 5 is a graph showing changes over time in measured values of magnetic flux density in a laminated core 50 as a comparative example; FIG. 2 is a diagram showing magnetic flux density measurement locations in the laminated core 1 according to the embodiment of the present invention; FIG. 4 is a diagram showing changes over time in measured values of magnetic flux density in the laminated core 1 according to one embodiment of the present invention; 1 is a configuration diagram of a laminated core 1A according to an embodiment of the present invention; FIG. 1 is a configuration diagram of a laminated core 1B according to one embodiment of the present invention; FIG. 1 is a configuration diagram of a laminated core 1C according to one embodiment of the present invention; FIG.

Hereinafter, a laminated core and a transformer according to embodiments will be described with reference to the drawings. In each drawing, the dimensions and scale of each part are appropriately different from the actual ones. In addition, since the embodiments described below are preferred specific examples, various technically preferable limitations are attached. are not limited to these forms unless

1. First Embodiment Hereinafter, a laminated core according to a first embodiment and a transformer provided with the laminated core will be described with reference to FIGS. 1 to 9. FIG.

1.1 Configuration of First Embodiment FIG. 1 is a configuration diagram of a laminated core 1 of a three-phase tripod according to a first embodiment. The laminated core 1 is configured by joining yoke portions 2A and 2B, outer leg iron portions 3A and 3B, and a central leg iron portion 4. As shown in FIG. More specifically, the yoke portions 2A and 2B are arranged such that the longitudinal directions of the outer leg portions 3A and 3B and the central leg portion 4 are positioned perpendicular to the longitudinal direction of the yoke portions 2A and 2B. 2B is joined with the outer leg iron portions 3A and 3B and the central leg iron portion 4.

In this specification, the yoke portions 2A and 2B may be collectively referred to as "yoke portion 2". Similarly, the outer leg irons 3A and 3B may be collectively referred to as "outer leg irons 3".

Also, in the following description, X-, Y-, and Z-axes that are orthogonal to each other are assumed. The X-axis, Y-axis and Z-axis are common in all the drawings illustrated in the following description. As exemplified in FIG. 1, one direction along the X axis when viewed from an arbitrary point is denoted as X1 direction, and the opposite direction to X1 direction is denoted as X2 direction. The X-axis direction is a direction including both the X1 direction and the X2 direction. Similarly, mutually opposite directions along the Y-axis from an arbitrary point are denoted as Y1 direction and Y2 direction. The Y-axis direction is a direction including both the Y1 direction and the Y2 direction. Also, directions opposite to each other along the Z-axis from an arbitrary point are denoted as Z1 direction and Z2 direction. The Z-axis direction is a direction including both the Z1 direction and the Z2 direction. Furthermore, the XY plane, which includes the X and Y axes, corresponds to the horizontal plane. The Z-axis is the axis along the vertical direction.

In particular, in FIG. 1, the longitudinal direction of the yoke portions 2A and 2B is the X-axis direction, and the longitudinal direction of the outer leg portions 3A and 3B and the central leg portion 4 is the Y-axis direction. Further, comparing the yoke portion 2A and the yoke portion 2B, the yoke portion 2A is positioned in the Z2 direction with respect to the yoke portion 2B. Further, when the outer leg iron portion 3A and the outer leg iron portion 3B are compared, the outer leg iron portion 3A is positioned in the X2 direction with respect to the outer leg iron portion 3B. The central leg iron portion 4 is positioned in the middle between the outer leg iron portion 3A and the leg iron portion 3B.

The yoke portion 2A and the yoke portion 2B are formed by laminating a predetermined number of grain-oriented electrical steel sheets whose rolling direction is the X-axis direction in the Y-axis direction while being insulated from each other. Further, the yoke portion 2A and the yoke portion 2B have the directionality of magnetism in the rolling direction. Directionality of magnetism of the yoke portion 2A and the yoke portion 2B is indicated by an arrow A in FIG.

The outer leg iron portions 3A and 3B and the central leg iron portion 4 are formed by laminating a predetermined number of grain-oriented electrical steel sheets whose rolling direction is the Z-axis direction in the Y-axis direction while being insulated from each other. ing. Further, the outer leg iron portions 3A and 3B and the central leg iron portion 4 have the magnetic orientation in the rolling direction. The orientation of the magnetism of the outer leg irons 3A and 3B and the central leg iron 4 is indicated by arrow B in FIG.

Coil portions 5A to 5C are attached to the outer leg iron portions 3A and 3B and the central leg iron portion 4. As shown in FIG. More specifically, the coil portion 5A is attached to the outer leg iron portion 3A, the coil portion 5B is attached to the central leg iron portion 4, and the coil portion 5C is attached to the outer leg iron portion 3B. In FIG. 1, the coil portions 5A to 5C are indicated by imaginary lines. Also, when the laminated core 1 is used in a transformer, the coil sections 5A to 5C include primary coils and secondary coils. The primary coil and the secondary coil are concentrically wound around the outer leg iron portions 3A and 3B and the central leg iron portion 4. As shown in FIG.

In this specification, the coil portions 5A to 5C may be collectively referred to as "coil portion 5".

The yoke portion 2A and the yoke portion 2B are provided with recesses 7A and 7B in regions including at least part of the interfaces 6A and 6B with the central leg iron portion 4, respectively. Each of 7A and 7B is fitted with a non-directional member 8A and 8B. The non-directional members 8A and 8B are formed by laminating a predetermined number of non-oriented steel plates in the Y-axis direction while being insulated from each other. The shape of the non-directional members 8A and 8B is preferably rectangular in the XZ plane, but is not limited to this. Also, the width of the non-directional members 8A and 8B in the X-axis direction preferably matches the width of the central leg iron portion 4 in the X-axis direction, but is not limited to this. Further, when the non-directional members 8A and 8B are rectangular in the XZ plane, the non-directional member 8A may be located in the Z2 direction from the interface 6A in the yoke portion 2A, or the non-directional member 8B may be located in the yoke portion 2A. If the portion 2B is located in the Z1 direction from the interface 6B, the effect of suppressing the wraparound of the magnetic flux is reduced. Therefore, of the two sides in the X-axis direction of the non-directional member 8A, the Z1-side side is aligned with the interface 6A. coincides with the interface 6B, but is not limited to this.

In this specification, the interfaces 6A and 6B may be collectively referred to as "interface 6". Similarly, recesses 7A and 7B may be collectively referred to as "recesses 7". Similarly, non-directional members 8A and 8B may be collectively referred to as "non-directional members 8".

Also, the maximum length of the non-directional members 8A and 8B in the Z-axis direction is 1/2 or less of the length of the yoke portions 2A and 2B in the Z-axis direction, as will be described later. /2 is preferable. This is the area where the magnetic flux can smoothly circulate around the nondirectional members 8A and 8B when the magnetic flux circulates through the yoke portion 2A, the leg iron portion 3A, the yoke portion 2B, and the leg iron portion 3B. is ensured to some extent, and the degree of induction of the magnetic flux to the central leg iron portion 4 by the non-directional members 8A and 8B is suppressed. However, the maximum length of the nondirectional members 8A and 8B in the Z-axis direction is not limited to this.

In addition, the silicon content of the non-oriented electrical steel sheets constituting the non-oriented members 8A and 8B is in the direction of forming the yoke portions 2A and 2B, the outer leg iron portions 3A and 3B, and the central leg iron portion 4. It is higher than the silicon content of the elastic electrical steel sheet. This is because, as will be described later, the magnetic flux concentrates at the T-shaped joint where the non-directional members 8A and 8B are arranged, and the magnetic flux density increases, which tends to increase iron loss. Materials with lower core losses are preferably those with low electrical conductivity due to their relatively high silicon content. Specifically, the silicon content of the grain-oriented electrical steel sheets forming the yoke portions 2A and 2B, the outer leg portions 3A and 3B, and the central leg portion 4 is preferably 2% to 5%. , and it is particularly preferable to set it to around 3%. On the other hand, the silicon content of the non-oriented electrical steel sheets constituting the non-oriented members 8A and 8B is preferably higher than the silicon content of the grain-oriented electrical steel sheets, and is preferably 7% or less. A value of around 0.5% is preferable. This is because if the silicon content of the non-oriented electrical steel sheet exceeds 7%, the physical properties, especially the magnetism and rigidity, are degraded. Magnetostrictive properties can be mentioned as properties related to magnetism. An electrical steel sheet with a silicon content of 6.5% has nearly zero magnetostriction, which is effective in suppressing noise and vibration in transformers.

Furthermore, the silicon content in the ends of the non-oriented electrical steel sheets constituting the non-oriented members 8A and 8B, specifically in the X-axis direction, is higher than that in the center. is preferred. As will be described later, in the nondirectional members 8A and 8B, magnetic flux is generated at the ends in the X-axis direction and near the interfaces 6A and 6B, that is, at the corners less than a predetermined distance from the interfaces 6A and 6B. This is because Due to this, iron loss at the corner tends to increase. Therefore, it is preferable to use a material with a high silicon content for lower core loss for the corner portion.

The yoke parts 2A and 2B, the outer leg iron parts 3A and 3B, and the central leg iron part 4 are composed of the grain-oriented magnetic steel sheets, and the non-oriented members 8A and 8B are composed of the non-oriented magnetic steel sheets. The thickness of is preferably about 0.30 mm to 0.35 mm, but is not limited to this.

1.2 Manufacturing Method of Embodiment FIG. 2 is an explanatory view showing an example of a manufacturing method of the laminated core 1 according to the first embodiment. FIG. 2 shows a state in which the ends of the outer leg irons 3A and 3B and the central leg iron 4 are joined to the yoke 2B including the non-directional member 8B. In this state, with respect to the outer leg iron portions 3A and 3B and the central leg iron portion 4, the coil portions 5A to 5C surround the outer leg iron portions 3A and 3B and the central leg iron portion 4. It is mounted from the Z2 direction to the Z1 direction so as to do. The yoke 2A including the non-directional member 8A is then joined to the outer leg irons 3A and 3B and the central leg iron 4. FIG. A laminated core 1 used in a transformer is constructed by this manufacturing method.

2, joint portions 2F and 3F between the yoke portion 2A and the leg iron portion 3A, joint portions 2G and 3G between the yoke portion 2A and the leg iron portion 3B, and a central leg iron portion 4, which are hatched in FIG. and non-directional member 8A, joint portions 4G and 8I between the central leg iron portion 4 and the non-directional member 8B, and joint between the concave portion 7A of the yoke portion 2A and the non-directional member 8A. The portions 7F and 8F and the joint portions 7G and 8G between the concave portion 7B of the yoke portion 2B and the non-directional member 8B are joined to each other by a lap joint method. Specifically, a method is used in which a lap margin is provided so that each joint is alternately displaced and overlapped for each lamination, and the lap margins of different members are joined together. However, the lap joint method is only an example, and the method of joining the respective members is not limited to the lap joint method.

Moreover, the manufacturing method shown in FIG. 2 is merely an example, and it is possible to manufacture the laminated core 1 by other methods. For example, first, the yoke portion 2A including the non-directional member 8A is joined to the ends of the outer leg iron portions 3A and 3B and the central leg iron portion 4, and then the coil portions 5A to 5C are formed. , the outer leg irons 3A and 3B and the central leg iron 4 are mounted from the Z1 direction to the Z2 direction, and finally the yoke 2B including the non-directional member 8B is mounted on the outer side. may be joined to the ends of the leg irons 3A and 3B and the center leg iron 4.

1.3 Shape of Path through which Magnetic Flux Flows FIG. 3 shows simulation results of the shape of the path through which magnetic flux generated in the laminated core 1 in the first embodiment flows. FIG. 3 shows the path through which the magnetic flux flows in the laminated core 1 at a certain moment. In the example of FIG. It shows the flow of magnetic flux at the moment when it circulates around the iron part 2B and the outer leg iron part 3B.

Since the magnetic flux tends to flow over a shorter distance, in the example of FIG. , with a higher tendency to flow through more medial routes. For this reason, more magnetic flux flows through the inner route, and the local magnetic flux density increases.

In addition, since the yoke portions 2A and 2B have a magnetic direction indicated by A as magnetic anisotropy, magnetic flux flows from the yoke portions 2A and 2B into the central leg iron portion 4 at the T-shaped joint. At this time, as shown in the circle P1 in FIG. ₃ , some of the magnetic flux passes through the central leg iron 4, and then flows into the central leg iron 4. . However, due to the presence of the non-directional members 8A and 8B, the magnetic flux flowing on the opposite side of the non-directional members 8A and 8B in the yoke portions 2A and 2B as shown in the circle P2 in _FIG . are guided to be absorbed by the non-directional members 8A and 8B without turning around. After that, the magnetic flux absorbed by the non-directional members 8A and 8B was absorbed by the non-directional members 8A and 8B according to the directionality of the magnetism indicated by B as the magnetic anisotropy in the central leg iron 4. From a position, flow straight down or straight up. Although details will be described later, due to the induction of magnetic flux by the non-directional members 8A and 8B, the magnetic flux density in the central leg iron portion 4 is reduced compared to the case where the non-directional members 8A and 8B are not arranged. also reduces iron loss in the laminated core 1 .

1.4 Comparison of Iron Loss Next, a comparison of iron loss densities between the laminated core 1 according to the present embodiment and the laminated core 50 as a comparative example will be described with reference to FIGS. FIG. 4 is a diagram showing the configuration of a laminated core 50 as a comparative example and its iron loss density distribution. FIG. 5 is a diagram showing the configuration of the laminated core 1 according to this embodiment and its core loss density distribution.

A laminated core 50 according to the comparative example is configured by joining yoke portions 20A and 20B, outer leg iron portions 30A and 30B, and a central leg iron portion 40 . More specifically, the yoke portions 20A and 20B are arranged so that the longitudinal directions of the outer leg portions 30A and 30B and the central leg portions 40 are perpendicular to the longitudinal direction of the yoke portions 20A and 20B. 20B, outer leg iron portions 30A and 30B, and central leg iron portion 40 are joined.

Particularly, in FIG. 4, the longitudinal direction of the yoke portions 20A and 20B is the X-axis direction, and the longitudinal direction of the outer leg iron portions 30A and 30B is the Y-axis direction. Further, comparing the yoke portion 20A and the yoke portion 20B, the yoke portion 20A is positioned in the Z2 direction with respect to the yoke portion 20B. Further, when the outer iron leg portion 30A and the iron leg portion 30B are compared, the iron leg portion 30A is positioned in the X2 direction with respect to the iron leg portion 30B. The central leg iron portion 40 is positioned in the middle between the outer leg iron portions 30A and 30B.

The yoke portions 20A and 20B are formed by laminating a predetermined number of grain-oriented electrical steel sheets whose rolling direction is the X-axis direction in the Y-axis direction while being insulated from each other. Furthermore, the yoke portions 20A and 20B have the directionality of magnetism in the rolling direction. The directionality of the magnetism of the yoke portions 20A and 20B is indicated by arrow A in FIG.

The outer leg iron portions 30A and 30B and the central leg iron portion 40 are formed by laminating a predetermined number of grain-oriented electrical steel sheets in the Y-axis direction while being insulated from each other and having the Z-axis direction as the rolling direction. ing. Further, the outer leg iron portions 30A and 30B and the central leg iron portion 40 have the magnetic orientation in the rolling direction. The orientation of the magnetism of the outer leg irons 30A and 30B and the central leg iron 40 is indicated by arrows B in FIG.

Comparing the laminated core 50 according to the comparative example with the laminated core 1 according to the present embodiment, the laminated core 50 according to the comparative example does not include the non-directional members 8A and 8B at the T-shaped joints. It is different from the laminated core 1 according to the form. In the laminated core 50 according to the comparative example, substantially V-shaped recesses 25A and 25B are provided in each of the yoke portions 20A and 20B, and both ends of the central leg iron portion 40 are formed substantially in a V shape, Both ends of the central leg iron portion 40 are joined to the concave portions 25A and 25B.

In this specification, the yoke portions 20A and 20B may be collectively referred to as "yoke portion 20". Similarly, the outer leg irons 30A and 30B may be collectively referred to as "outer leg irons 30". Similarly, recesses 25A and 25B may be collectively referred to as "recesses 25".

Next, the iron loss density distribution of the laminated core 50 according to the comparative example and the iron loss density distribution of the laminated core 1 according to this embodiment will be compared. In the yoke parts 2A and 2B, the outer leg iron parts 3A and 3B, and the central leg iron part 4, excluding the non-directional members 8A and 8B, of the laminated core 1 according to the present embodiment, the iron shown in FIG. The area of the region of high iron loss is larger than the area of the region of similarly high iron loss in the yoke portions 20A and 20B, the outer leg iron portion 30, and the central leg iron portion 40 of the laminated core 50 according to the comparative example. is also narrow.

In cores used in transformers, core losses mainly include hysteresis loss generated when the direction of the magnetic field changes in the core and eddy current loss caused by eddy currents generated in the core. Hysteresis loss is calculated by the following formula [1]. Also, the eddy current loss is calculated by the following formula [2]. In the following formulas [1] and [2], the hysteresis loss is _Ph [W/kg], the frequency is f [Hz], the maximum magnetic flux density is B _m [T], and the eddy current loss is _Pe [ W/kg], the thickness of the steel sheet is t [m], the voltage form factor is _kf , and _kh and _ke are constants determined by the material.

As shown in the above formulas [1] and [2], both the hysteresis loss _Ph and the eddy current loss _Pe increase as the maximum magnetic flux density _Bm increases. Therefore, in order to reduce core loss, it is preferable to reduce the maximum magnetic flux density _Bm . As will be described later, the magnetic flux phase deviation in the laminated core 1 according to the present embodiment is smaller than that in the laminated core 50 according to the comparative example. As a result, the magnetic flux cancels out each other to a lesser extent, so under the condition that the total magnetic flux is constant, a very high magnetic flux density is not required. Moreover, in the laminated core 1 according to the present embodiment, the degree of unevenness in the magnetic flux density distribution is small. That is, in the laminated core 1 according to the present embodiment, since there is little tendency to generate areas where the magnetic flux density is locally high, it is presumed that the core loss density is relatively low. Furthermore, in the T-shaped joint, the path through which the magnetic flux flows is complicated and confused, so it is not preferable to use a material having a specific directivity as in the comparative example. At the same time, by using the non-directional member 8 at the T-shaped joint, magnetic flux from any direction can be induced to the central leg iron portion 4 . As a result, in the laminated core 1 according to the present embodiment, the total iron loss can be reduced by around 1.5% compared to the laminated core 50 according to the comparative example.

On the other hand, in the laminated core 1 according to the present embodiment, as described above, in the nondirectional members 8A and 8B, the iron loss density Is high. This is because more magnetic flux concentrates at the corners because the magnetic flux tends to follow a shorter route. Therefore, as described above, the silicon content of the ends of the non-oriented electrical steel sheets constituting the non-oriented members 8A and 8B, specifically, the ends of the non-oriented electrical steel sheets in the X-axis direction is , preferably higher than the silicon content in the center. As a result, the effect of reducing the total iron loss described above is further increased.

1.5 Comparison of Magnetic Flux Density Distribution Next, a comparison of magnetic flux density distributions between the laminated core 1 according to the present embodiment and the laminated core 50 as a comparative example will be described with reference to FIGS. . FIG. 6 is a diagram showing magnetic flux density measurement locations in a laminated core 50 as a comparative example. FIG. 7 is a graph showing changes over time in magnetic flux density measurements at the respective measurement locations shown in FIG. FIG. 8 is a diagram showing measurement points of the magnetic flux density in the laminated core 1 according to this embodiment. FIG. 9 is a graph showing changes over time in the measured values of the magnetic flux density at each measurement point shown in FIG.

As shown in FIG. 6, the central portion in the Z-axis direction of the central leg iron portion 40 provided in the laminated core 50 as the comparative example is divided into seven at equal intervals from the X2 direction to the X1 direction. The five points are defined as measurement point M _C1 , measurement point M _C2 , measurement point M _C3 , measurement point M _C4 , and measurement point M _C5 from the X2 direction toward the X1 direction. In the laminated core 50 as a comparative example, the magnetic flux densities at these measurement points M _C1 to M _C5 are measured. Similarly, as shown in FIG. 8, the central portion in the Z-axis direction of the central leg iron portion 4 provided in the laminated core 1 according to the present embodiment is divided into seven at equal intervals from the X2 direction to the X1 direction, The five division points are assumed to be measurement point M _E1 , measurement point M _E2 , measurement point M _E3 , measurement point M _E4 , and measurement point M _E5 from the X2 direction toward the X1 direction. In the laminated core 1 according to this embodiment, magnetic flux densities are measured at these measurement points M _E1 to M _E5 .

As described above, FIG. 7 shows changes over time in the measured values of magnetic flux density at measurement points M _C1 , M _C2 , M _C3 , M _C4 , and M _C5 . Similarly, FIG. 9 shows temporal changes in the measured values of the magnetic flux densities at the measurement point M _E1 , the measurement point M _E2 , the measurement point M _E3 , the measurement point M _E4 , and the measurement point M _E5 . Comparing FIG. 7 and FIG. 9, the maximum value of the magnetic flux density shown in FIG. 7 exceeds one while the maximum value of the magnetic flux density shown in FIG. 9 is below one. That is, the maximum value of the magnetic flux density in the laminated core 1 according to the present embodiment is smaller than the maximum value of the magnetic flux density in the laminated core 50 as the comparative example. Also, the interval between peaks in each graph in FIG. 9 is smaller than the interval between peaks in each graph in FIG. That is, the magnetic flux phase shift in the laminated core 1 according to the present embodiment is smaller than the magnetic flux phase shift in the laminated core 50 as the comparative example. This is due to the fact that the wraparound of the magnetic flux is reduced as exemplified in the circle _P1 in FIG. This is because the As a result, the degree to which the magnetic fluxes cancel each other is reduced, so that the necessary magnetic flux density is reduced when the total amount of magnetic flux in the central leg iron portion 4 is kept constant. Therefore, it can be said that the iron loss in the laminated core 1 according to the present embodiment is lower than the iron loss in the laminated core 50 as the comparative example.

1.6 Effects of First Embodiment The following effects can be obtained in this embodiment.

A laminated core 1 according to the present embodiment includes a yoke portion 2 and a leg iron portion 4 which is arranged in a direction perpendicular to the yoke portion 2 and in which grain-oriented electromagnetic steel sheets having a first magnetic directionality are laminated. The yoke portion 2 is laminated with grain-oriented electrical steel sheets having a second magnetic directionality perpendicular to the first magnetic directionality, and the yoke portion 2 and the leg iron portion 4 are laminated. It comprises a directional member having a recess 7A provided in a region including a part of the interface 6A, and a non-directional member 8 in which non-oriented electrical steel sheets are laminated and which is fitted in the recess 7A of the directional member.

As a result, the laminated core 1 can further reduce iron loss by a simpler method than conventional laminated cores.

Further, in the laminated core 1 according to the present embodiment, the above-described yoke portion 2 is the first yoke portion 2A, the above-described directional member is the first directional member, and the above-described non-directional member 8 is the first non-directional member 8A and comprises the second yoke portion 2B. The second yoke portion 2B is formed by laminating grain-oriented electrical steel sheets having a second magnetic orientation. A second directional member having a recessed portion 7B provided in a region including a part of the interface 6B between the second yoke portion 2B and the leg iron portion 4, and a recessed portion 7B of the second directional member. , and a second non-directional member 8B laminated with non-oriented electrical steel sheets.

This makes it possible to use the laminated core 1 as a laminated core for a three-phase transformer.

Further, in the laminated core 1 according to the present embodiment, the first nondirectional member 8A and the second nondirectional member 8B may use all of the interfaces 6A and 6B as part of the end faces.

As a result, the first non-directional member 8A and the second non-directional member 8B can induce more magnetic flux to the leg iron portion 4. As shown in FIG.

Further, in the laminated core 1 according to the present embodiment, the maximum value of the length in the thickness direction perpendicular to the interfaces 6A and 6B between the first nondirectional member 8A and the second nondirectional member 8B is the yoke portion It may be half or less of the length in the thickness direction perpendicular to the interfaces 6A and 6B of 2A and 2B.

As a result, when the magnetic flux circulates around the yoke portion 2A, the outer leg iron portion 3A, the yoke portion 2B, and the outer leg iron portion 3B, it is guided to the central leg iron portion 4 by the non-directional members 8A and 8B. It is possible to further reduce the degree of

Moreover, in the laminated core 1 according to the present embodiment, the silicon content of the non-oriented electrical steel sheets may be higher than the silicon content of the grain-oriented electrical steel sheets.

This makes it possible to further reduce iron loss in the non-directional members 8A and 8B where the magnetic flux concentrates.

In addition, in the non-oriented electrical steel sheet of the laminated core 1 according to the present embodiment, the silicon content at the ends in the longitudinal direction of the yoke portions 2A and 2B may be higher than the silicon content at the central portion.

As a result, it is possible to further reduce iron loss particularly at the corner portions of the non-directional member 8 where the magnetic flux concentrates.

Also, the transformer according to the present embodiment includes the above-described laminated core 1 and primary and secondary coils wound around the laminated core 1 .

As a result, it is possible to realize a transformer with a reduced iron loss and an improved transformation efficiency as compared with the conventional technology.

2. Second Embodiment Hereinafter, a laminated core according to a second embodiment will be described with reference to FIG.

2.1 Configuration of Second Embodiment FIG. 10 is a configuration diagram of a three-phase three-legged laminated core 1A according to a second embodiment. In the following, for simplification of explanation, differences between the laminated core 1A according to the second embodiment and the laminated core 1 according to the first embodiment will be explained. In particular, the same reference numerals are used for the same constituent elements in the laminated core 1A and the laminated core 1, and descriptions mainly relating to their functions may be omitted.

In the laminated core 1A according to the second embodiment, unlike the laminated core 1 according to the first embodiment, the non-directional members 8A are arranged from the X2 direction to the X1 direction in the order of the non-directional members 8P, the non-directional It is divided into three parts, a member 8Q and a non-directional member 8R. Similarly, the nondirectional member 8B is divided into three nondirectional members 8S, 8T, and 8U from the X2 direction toward the X1 direction. Furthermore, the silicon content of the non-oriented electrical steel sheets forming the non-oriented member 8P and the non-oriented member 8R is higher than the silicon content of the non-oriented magnetic steel sheet forming the non-oriented member 8Q. Similarly, the silicon content of the non-oriented electrical steel sheets that form the non-oriented members 8S and 8U is higher than the silicon content of the non-oriented electrical steel sheets that form the non-oriented member 8T.

As described above, in the nondirectional members 8A and 8B, the magnetic flux is concentrated at the corners which are the ends in the X-axis direction and near the interfaces 6A and 6B, that is, at less than a predetermined distance from the interfaces 6A and 6B. As a result, iron loss at the corner tends to increase. Corresponding to this, in the laminated core 1A according to the second embodiment, the silicon content of the non-oriented electrical steel sheets constituting the non-oriented member 8P and the non-oriented member 8R, which tend to increase iron loss, is It is higher than the silicon content of the non-oriented electrical steel sheet that constitutes the non-oriented member 8Q. Similarly, the silicon content of the non-oriented electrical steel sheets constituting the non-oriented member 8S and the non-oriented member 8U, which tend to have high iron loss, is is higher than the silicon content of

In the laminated core 1A shown in FIG. 10, the non-directional member 8A is divided into three non-directional members 8P, 8Q and 8R. is divided into three non-directional members 8S, 8T, and 8U, but this is an example and not a limitation. The nondirectional members 8A and 8B can be divided into arbitrary numbers.

2.2 Effects of Second Embodiment The following effects can be obtained in this embodiment.

In the non-oriented electrical steel sheets that constitute the non-oriented member 8A of the laminated core 1A according to the present embodiment, the The silicon content of the non-oriented electrical steel sheet is higher than that of the non-oriented electrical steel sheet forming the non-oriented member 8Q, which is the central portion. Similarly, in the non-oriented electrical steel sheets that form the non-oriented member 8B, the silicon-containing silicon-containing The ratio is higher than the silicon content of the non-oriented electrical steel sheet forming the non-oriented member 8T, which is the central portion.

As a result, the laminated core 1A can further reduce iron loss particularly at the corner portions of the nondirectional members 8A and 8B where the magnetic flux concentrates.

3. Third Embodiment Hereinafter, a laminated core according to a third embodiment will be described with reference to FIG. 11 .

3.1 Configuration of Third Embodiment FIG. 11 is a configuration diagram of a three-phase three-phase laminated core 1B according to a third embodiment. In the following, for simplification of explanation, differences of the laminated core 1B according to the third embodiment from the laminated core 1 according to the first embodiment will be explained. In particular, the same reference numerals are used for the same constituent elements in the laminated core 1B and the laminated core 1, and explanations mainly relating to their functions may be omitted.

In a laminated core 1B according to the third embodiment, unlike the laminated core 1 according to the first embodiment, each of the yoke parts 2A and 2B is replaced by the rectangular recesses 7A and 7B in the XZ plane of FIG. has two triangular recesses 9A and 9B and two triangular recesses 9C and 9D. These concave portions 9A to 9D are right-angled triangles in the XZ plane of the drawing. More specifically, this right-angled triangle has the ends of the interfaces 6A and 6B as vertices of the right angle, and a line segment of a part of the interfaces 6A and 6B starting from the vertices as one side, and the vertices as the starting points. Then, a line segment perpendicular to the interfaces 6A and 6B is taken as another side. In the laminated core 1B, nondirectional members 10A to 10D are fitted in each of a total of four recesses 9A to 9D in the yoke portions 2A and 2B.

In this specification, the concave portions 9A to 9D may be collectively referred to as "the concave portions 9". Similarly, the non-directional members 10A-10D may be collectively referred to as the "non-directional member 10."

As described above, in the non-directional members 8A and 8B, the corners that are the ends of the yoke portion 2 in the X-axis direction and are near the interfaces 6A and 6B, that is, less than a predetermined distance from the interfaces 6A and 6B. Iron loss tends to be high at the corner portion due to the concentration of magnetic flux at the corner portion. In the laminated core 1B according to the third embodiment, the non-directional members 10A to 10D made of non-oriented magnetic steel sheets having a higher silicon content than the grain-oriented magnetic steel sheets that make up the directional members are only the corner portions. placed in

3.2 Effects of the Third Embodiment The following effects can be obtained in this embodiment.

In the laminated core 1B according to the present embodiment, the first non-directional members 10A and 10B and the second non-directional members 10C and 10D have part of the interfaces 6A and 6B as part of the end face.

As a result, the laminated core 1B can reduce the iron loss in the laminated core 1B at a lower cost by saving the amount of costly non-oriented electrical steel sheets with a high silicon content.

4. Fourth Embodiment Hereinafter, a laminated core according to a fourth embodiment will be described with reference to FIG. 12 .

4.1 Configuration of Fourth Embodiment FIG. 12 is a configuration diagram of a three-phase tripod laminated core 1C according to a fourth embodiment. In the following, for simplification of explanation, differences between the laminated core 1C according to the fourth embodiment and the laminated core 1 according to the first embodiment will be explained. In particular, the same reference numerals are used for the same constituent elements in the laminated core 1C and the laminated core 1, and explanations mainly relating to their functions may be omitted.

Unlike the laminated core 1 according to the first embodiment, in the laminated core 1C according to the fourth embodiment, in addition to the non-directional member 11A provided inside the yoke portion 2A, Outside the leg 4, a non-directional member 12A having a first end face on the Z1 direction side of the yoke 2A and a second end face on the X2 direction side of the central leg 4 is provided. be provided. Similarly, outside the yoke portion 2A and the central leg portion 4, the side surface of the yoke portion 2A on the Z1 direction side is the first end surface, and the side surface of the central leg portion 4 on the X1 direction side is the second end surface. A non-directional member 12B is provided such that Similarly, in addition to the non-directional member 11B provided inside the yoke portion 2B, outside the yoke portion 2B and the central leg iron portion 4, the side surface of the yoke portion 2B on the Z2 direction side is the first A non-directional member 12C is provided such that the side surface of the central leg iron portion 4 on the X2 direction side serves as the second end surface. Similarly, outside the yoke portion 2B and the central leg portion 4, the side surface of the yoke portion 2B on the Z2 direction side is the first end surface, and the side surface of the central leg portion 4 on the X1 direction side is the second end surface. A non-directional member 12D is provided such that

Further, the non-directional members 12A and 12B are provided between the first end face and the second end face that are perpendicular to each other so that the side of the intersection line between the first end face and the second end face is convex as the third end face. It has a cylindrical surface. Similarly, the non-directional members 12C and 12D are provided between the first end face and the second end face that are perpendicular to each other, and the side of the intersection line between the first end face and the second end face is convex as the third end face. It has a cylindrical surface like

In the XZ plane of FIG. 12, the nondirectional member 11A provided inside the yoke portion 2A has a rectangular shape, and of the two sides in the X-axis direction, the side on the Z1 direction side includes the interface 6A and is non-directional. It is preferable to match the sum of the X-axis direction width of the first end faces of the directional members 12A and 12B and the X-axis direction width of the central leg iron portion 4 . Similarly, the non-directional member 11B provided inside the yoke portion 2B has a rectangular shape. and the width of the central leg iron portion 4 in the X-axis direction.

In this specification, the non-directional members 12A to 12D may be collectively referred to as "non-directional members 12".

Further, the non-directional member 12 is not limited to the T-shaped joint between the yoke portions 2A and 2B and the central leg iron portion 4. It may be placed at the junction.

4.2 Effects of the Fourth Embodiment As described with reference to FIG. 3, the magnetic flux that circulates in the laminated core tends to circulate in a shorter route. Therefore, as shown in FIG. 5, in the non-directional members 8A and 8B, corners that are ends in the X-axis direction and near the interfaces 6A and 6B, that is, less than a predetermined distance from the interfaces 6A and 6B Iron loss tends to be high at the corner portion due to the concentration of magnetic flux at the corner portion. The laminated core 1C according to the present embodiment is provided with the non-directional members 12A to 12D including cylindrical surfaces at the corners where the magnetic flux concentrates, thereby alleviating the concentration of the magnetic flux at the corners and eventually reducing iron loss. can be reduced.

1, 1A, 1B, 1C... laminated core, 2, 2A, 2B... yoke portion, 2F, 2G... joint portion, 3, 3A, 3B... outer leg iron portion, 4... central leg iron portion, 5, 5A, 5B, 5C... coil portion, 6, 6A, 6... interface, 7, 7A, 7B... concave portion, 7F, 7G... joint portion, 8, 8A, 8B, 8P, 8Q, 8R, 8S, 8T, 8U... non-directional members 9, 9A, 9B, 9C, 9D ... concave portions 10, 10A, 10B, 10C, 10D, 11, 11A, 11B, 12, 12A, 12B, 12C, 12D ... non-directional members, 20, 20A, 20B... yoke portion, 25, 25A, 25B... concave portion, 30, 30A, 30B... outer leg iron portion, 40... central leg iron portion, 50... laminated core

Claims (9)

yoke section;
a leg iron portion arranged in a direction perpendicular to the yoke portion and laminated with grain-oriented electrical steel sheets having a first magnetic orientation;
The yoke portion
A grain-oriented electrical steel sheet having a second magnetic orientation perpendicular to the first magnetic orientation is laminated and provided in a region including a part of the interface between the yoke portion and the leg iron portion. a directional member having a recessed portion;
a non-directional member in which non-oriented electrical steel sheets are laminated and which is fitted in the concave portion of the directional member;
Laminated core. The yoke portion is a first yoke portion, the directional member is a first directional member, the non-directional member is a first non-directional member,
Equipped with a second yoke,
The second yoke portion is
A second direction-oriented member in which grain-oriented electrical steel sheets having the second directionality of magnetism are laminated and having a concave portion provided in a region including a part of an interface between the second yoke portion and the leg iron portion. When,
2. The laminated core according to claim 1, further comprising: a second non-directional member in which non-oriented electrical steel sheets are laminated and which is fitted in the concave portion of the second direction-oriented member. 3. The laminated core according to claim 2, wherein said first non-directional member and said second non-directional member have a part of said interface as a part of an end face. 4. The laminated core according to claim 3, wherein said first non-directional member and said second non-directional member make said entire interface part of said end surface. A longitudinal side surface of the first yoke portion or the second yoke portion is defined as a first end surface, a longitudinal side surface of the leg iron portion is defined as a second end surface, and between the first end surface and the second end surface, A third non-oriented member having a third end surface that is a cylindrical surface convex on the intersection side of the first end surface and the second end surface, and further comprising a third non-oriented member in which non-oriented electrical steel sheets are laminated. The laminated core according to any one of claims 2 to 4. The maximum length of the thickness direction perpendicular to the interface between the first non-directional member and the second non-directional member is the length of the yoke portion in the thickness direction perpendicular to the interface. 6. The laminated core according to any one of claims 1 to 5, which is one-half or less of the. The laminated core according to any one of claims 1 to 6, wherein the silicon content of the non-oriented electrical steel sheets is higher than the silicon content of the grain-oriented electrical steel sheets. 8. The laminated core according to claim 7, wherein in the non-oriented electrical steel sheet, the silicon content in the longitudinal ends of the yoke portion is higher than the silicon content in the central portion. A laminated core according to any one of claims 1 to 8;
A transformer comprising a primary coil and a secondary coil wound around the laminated core.

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