JPS59210623A - Magnetic core - Google Patents

Abstract

PURPOSE:To reduce abnormal eddy current loss of a magnetic core by a method wherein magnetic material pieces of high electric resistance and high permeability are arranged coming in contact with open magnetic path surfaces consisting of the cut surfaces of the laminated magnetic core main bodies formed of magnetic material thin plates of high permeability, and having the edge faces of uncut surfaces facing mutually in parallel with the open magnetic path surfaces. CONSTITUTION:A laminated magnetic core main body 1 formed of magnetic material thin plates of high permeability has open magnetic path surfaces 1a at two parts, and the main body 1 is formed of at least one kind out of an amorphously magnetic material, Permalloy, a silicon steel plate, electromagnetic soft iron, and Sendust. Magnetic material pieces 2 having high electric resistance and high permeability are arranged coming in contact with the open magnetic path surfaces 1a of the main body 1, and the mutually facing edge surfaces in parallel with the path surfaces 1a are consisting of uncut surfaces. The magnetic material pieces 2 is formed of ferrite or a composite resin magnetic material formed by dispersing a powdered magnetic material in synthetic resin. Accordingly, iron loss of the magnetic core can be reduced by reducing abnormal eddy current loss at the case when the magnetic core has the open magnetic path surfaces consisting of the cut surfaces.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a magnetic core used in transformers, choke coils, etc.

[Background technology]

In general, in a laminated magnetic core formed of soft magnetic metal with high magnetic permeability, the core loss during AC excitation is divided into so-called iron loss, steresis loss Wh1, general eddy current loss We, and abnormal eddy current loss Wa. , its frequency characteristics are shown in Figure 1, and the hysteresis loss wh
does not change even if the frequency f changes, and both eddy current losses Wes
Wa increases as the frequency f becomes higher. Note that the composition ratio of each loss Wh, We, and Wa varies greatly depending on the shape of the magnetic/d material such as the plate thickness, heat treatment conditions, and the like. By the way, the above-mentioned general eddy current loss We is calculated by the following formula fl), where t is the thickness of the magnetic plate forming the laminated magnetic core, ρ is the electrical resistance, and Bm is the operating magnetic flux density. It is also called eddy current loss.

On the other hand, the abnormal eddy current loss Wa is the difference between the eddy current loss that actually occurs and the general eddy current loss We, and this abnormal eddy current loss Wa is strongly related to the magnetic domain structure and the number of domain walls. The plate thickness is calculated by the following equation (2), where t1 is the domain wall spacing and d is the domain wall spacing.

(Based on the Pry and Bean equation) Taking the above into consideration, conventionally, the narrow side of a silicon steel plate was scratched, and fine crystals were created inside the amorphous magnetic material. The abnormal eddy current loss Wa was reduced by increasing the number of domain walls in order to reduce iron loss. When a so-called gut core is formed, the abnormal eddy current loss Wa, which is thought to be due to the disturbance of magnetic flux in the lamination direction and the open magnetic path plane consisting of the cut surface that is directly fired, increases.
There is a problem in that the rate of increase in iron loss increases as the frequency f increases. For example, recently developed amorphous magnetic materials have lower iron loss than ferrite even in the high frequency range of several 100 KHz, so a magnetic material with a combination of two cut cores can be used.
Application to a 5-layer magnetic core is being considered, but despite the small iron loss in a closed-circuit magnetic core with a thousand sets (see Figure 2).
A laminated magnetic core in which strip-shaped thin films of amorphous magnetic material are wound and laminated as shown in (a) is cut as shown in (b) of the same figure.
When 1,000 seps (G) are formed as in c), there is a problem in that the iron loss increases.

That is, in a closed magnetic circuit core that is not cut, the operating magnetic flux density Bm is 3 K G-,', and the frequency f is 20 K) (z
In the case of , the iron loss of the magnetic core (5) using Mn-Zn ferrite is 200 mW% cc, while the magnetostrictive Z]
The iron loss of the magnetic core (a) using a Baltic amorphous magnetic material is 50 mW/cc, which is a fraction of the iron loss. However, Yuchi Yappu's laminated magnetic core (4
)', the iron loss of the one using an amorphous magnetic material was more than twice that of the one using ferrite. In addition,
Under conditions where the operating magnetic flux density Bm and frequency are the same, f
It was a common belief that by providing P, the excitation current increases and copper loss increases, but there is no increase in iron loss U. However, the reason why such an increase in iron loss actually occurs is considered to be as follows. In other words, a magnetic flux component perpendicular to the plate surface is generated in the open magnetic path plane, which is the cutting surface, and on the other hand, the magnetic domain structure changes due to the generation of spike domains and reflux magnetic domains near the open magnetic path section, and the domain walls in the magnetization process change. It is thought that this influences the shift mJ pattern and the number of domain walls, increasing the abnormal eddy current loss Wa.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to reduce abnormal thin current loss and iron loss when an open magnetic path surface consisting of a cut surface is provided.

[Disclosure of the invention]

(Structure) Figure 5 shows the structure of the present invention, and (1) is made of a thin plate made of a magnetic material with high magnetic permeability and having an open magnetic path surface (la) similar to a cut surface in part. This laminated magnetic core body +11 is made of one of amorphous magnetic materials, permanent magnets, silicon steel plates, electromagnetic soft iron, and sesitast. (2) is a piece of magnetic material with high electrical resistance and magnetic permeability, and is arranged in contact with the open magnetic path surface (1a) of the laminated magnetic core body (1), and has an opposing end surface parallel to the open magnetic path surface (1a). It has a non-cut surface. This magnetic piece (2) is made of a composite resin magnetic material in which ferrite or powdered magnetic material is dispersed in a synthetic resin.

Now, the magnetic material piece (2) with high electrical resistance and low occurrence of eddy current loss is attached to the laminated magnetic core body (open magnetic path surface (la) of 11).
In other words, they are placed in close contact with the opposing end surfaces of the laminated magnetic core (5), and the magnetic material pieces (2) are
), and since the first set (G) is formed with a non-cut surface, there is no bending of the magnetic flux or disturbance of the magnetic domain structure around the dry set part of the laminated magnetic core (3). Magnetic piece (2
), the general eddy current loss W
E and abnormal eddy current loss Wa can be reduced. Examples will be described in detail below.

(Example 1) Figure 4 shows an example of the invention, and the ribbon width is 10M.
, C with zero magnetostriction composition with thickness 625~5μ convexity.

Am-based amorphous body (Co-Si-B alloy)? Two wound magnetic cores (A
I) (A2) and both windings I-r (Al) (
When A2) is annealed to remove strain and then cooled with water, it is heat treated to reduce high frequencies by Tol, and an insulating adhesive resin is impregnated between the layers of the wound cores (A1 and A2) and between the two wound cores (Al) and (A2). Then, the central part is cut to form a type magnetic core (Aa) (Ab) as shown in FIG. 4(a). Here, the effective magnetic path length is 76/IM, and the central effect magnetic path cross-section is 6.
4-1 The width of the magnetic core is 4.9 cc, and the iron loss under operating conditions of operating magnetic flux tightness of 1 KG and frequency of 50 KHz is 30 in a state where no instep is formed in close contact with the vJTjfr surface.
mW/cc. This E4 magnetic core (Aa) (Ab)
(7) Air F sep (
When we measured the iron loss when expanding the unsaturated region of the B-H route by providing G), the iron loss was 75 mW/cc.
This is twice as much as when there is no air f-sep (G). Therefore, as shown in Fig. 4(b), a magnetic piece (2
) by arranging the thin plate (1.5 mm thick) in close contact with the open magnetic path surface formed by the cut surface, the increase in iron loss caused by the provision of the upper set (G) was reduced. That is, when Mn-Zn ferrite (effective magnetic permeability pe=2000 atl KG, 50KH2) is used as the magnetic piece (2), the iron loss is 42 mW.
7g=350atlKG, 50KHz), the iron loss is 50 mW/cc, Tl:rυ, and the one with high magnetic permeability has a greater effect of reducing iron loss by 1,000P tsura (G). I understand that. In addition, Fig. 5 shows the magnetic material piece (
2) shows an experimental method to confirm the change in the effect of reducing iron loss increase depending on the installation position. In Fig. 5(c), no reducing effect is obtained, and in Fig. 5(b), some reduction effect is obtained. The effect is obtained, and the most dog-like young fruit in the same figure (a) is obtained.

(Example 2) In the same configuration as in Example 1, Q of zero magnetostriction composition
Amorphous magnetic material (Co-Si-B alloy) is mechanically pulverized to form magnetic powder, and this magnetic powder is dispersed in sweet acid resin, which is highly resistant to staining. Form a composite magnetic material and use this composite magnetic material to create a magnetic material piece (2)
It became a novelty. Here, the synthetic resin is a phenolic resin, and the volume ratio of the phenolic resin is 50%, and the effective magnetic permeability μe of the composite magnetic material obtained in this way is 45.
It is.

As a result of carrying out the iron loss d(II construction) for Example 2 under the same conditions as the above-mentioned Example, the iron loss was 65 mW/cc, and the effect of reducing the increase in iron loss was recognized.

FIG. 6 shows -1! about the material of the magnetic piece (2) of Example 1.2 above. This is a diagram that visually shows the effect of reducing iron loss with Yatsupu (G). ? The higher the L magnetic property, the greater the effect of reducing iron loss.
It can be seen that the longer the length (p), the greater the effect. Disappearance, I create a complete release magnetic path as shown in Figure 7.
It has been confirmed that even when a magnetic piece (2) is provided on the end face of the patterned layer core (A type), a large iron loss reduction effect can be obtained. It was confirmed that a large iron loss reduction effect can be obtained even in cases where

(Example 3) FIG. 9 shows yet another example, in which an amorphous magnetic material (Fe40 Ni 38 Mo4B18.2a2a
mg.

Tast core (μ = 16.5,
I was afraid of the magnetic material piece t2) made of Tokyo Denki Kagakusha,
A choke coil is formed by winding a coil (not shown), and the desired intufftance can be achieved by appropriately adjusting the magnetic permeability of the first coil (C) and the magnetic material piece (2). This is what I did to get it.

Now, the iron Mtd+ of the choke coil in the case where a simple air drying septum is formed without inserting the magnetic material piece (2)
, ow (JfiJ wave number 50KHz, electric m, 0, 3A
(measured using the U-function correction), but in the example, it is 2.0 W, which means that the iron loss due to -ft' tube (G) can be greatly reduced. In addition to the above-mentioned amorphous magnetic materials, Fe7.9B16 Si
5, Fe7aB13Si9% C075B15Si1
o＼Co74Fe6B2o (all manufactured by Allied Chemical Co., Ltd.), and permeability gold-knit magnetic materials that can be used as amorphous magnetic materials include Perma 0i, Chrome Permalloy, Nansu Pudeci Perma-Oi, Mu-metal, Hypernic, and Nikka. O
I, 72 Matsuku people superma 0 I, etc.

(-Ah image example 4) Figure 10 shows yet another example of an acicular amorphous magnetic material. ) (For example, use C075B□5Si on as a low-viscosity tree (-]eha) Araltite CY230 manufactured by Cibagai Sen-sha; Hardener 1-IY956=lOO:18
, mixture viscosity 1500 mpa (25 °C)) to weight ratio 50
: When mixed at 50° C. and cured under the application of a magnetic field, a composite magnetic material (S) with needle-shaped amorphous magnetic materials (ω) facing the same direction is formed.
) is obtained, and the magnetic material piece (2) is obtained from this composite magnetic material (Company).
By forming this, the same iron loss reduction effect as in the above embodiment can be obtained.

In the example, the composite magnetic material (() has an average permeability μ in the X direction of 50, a resistivity in the y and Z directions greater than 106 Ωm, and the iron loss for a sine wave with a frequency of 20 KHz and a current of 0.5 A). When measured, it was 2.5W, and an effect of reducing iron loss was obtained.

In addition, the magnetic material piece (2) is placed in the direction perpendicular to the main magnetic path (y
, z direction), and the resistivity is high in the direction parallel to the main magnetic path (X
It is desirable to use a composite magnetic material (6) that has a magnetic permeability of 100 or less in the direction (direction) and does not saturate at the operating magnetic flux density.

〔Effect of the invention〕

As described above, the present invention includes a laminated magnetic core main body formed of a magnetic thin plate with high magnetic permeability and having an open magnetic path surface partially consisting of a cut surface, and an open magnetic core body in contact with the open magnetic path surface. The opposing end surface parallel to the road surface is a non-cutting surface and is different from a magnetic piece with high nausea resistance and magnetic permeability. Further, there is an advantage that abnormal eddy current loss caused by disorder of the magnetic domain structure can be reduced, and a magnetic core with little increase in core loss can be provided even when 4P points are formed.

[Brief explanation of the drawing]

Figure 1 shows the frequency characteristics of iron loss, Figure 2 (a) to (
c) is a perspective view showing the manufacturing process of the conventional example, and Fig. 5(a) (
b) is a perspective view showing the configuration of the present invention, Fig. 4 fa) (b)
) is a diagram showing the manufacturing process of one embodiment of the present invention, FIGS. 5 and 6 are explanatory diagrams of the same operation, FIGS. 7 and 8 are diagrams each showing other embodiments, and FIG. A perspective view of another embodiment. FIG. 10 is a perspective view of a main part of still another embodiment. (1) is the magnetic core body, and (2) is a magnetic piece. Agent Patent Attorney Ishi 1) Ai 7 Figure 3 Figure 5 Figure 6 Figure 8 Figure 7 Figure 9 and Figure 10 Procedural amendment (voluntary) 1. Indication of the case 1984 Patent Application No. 84376 2. Name of the invention Magnetic core 3. Relationship with the case of the person making the amendment Patent applicant address 1048 Bold Kadoma, Kadoma City, Osaka Name (583) Matsushita Electric Works Co., Ltd. Representative Iku Kobayashi 4, agent editing Correct application number: Japanese Patent Application No. 1, No. 58-84376, the scope of claims of this application is corrected as follows. [(1) A laminated magnetic core body formed of a magnetic thin plate with high magnetic permeability and having an open magnetic path surface partially consisting of a cut surface, and a laminated magnetic core body formed of a magnetic thin plate with high magnetic permeability, and a core body disposed in contact with the open magnetic path surface and parallel to the open magnetic path surface. A magnetic core consisting of a piece of magnetic material with high electrical resistance and magnetic permeability, and the opposing end surface is an uncut surface. (2) The magnetic core according to claim 1, wherein the laminated magnetic core body is formed of at least one of an amorphous magnetic material, a permanent magnetic material, a silicon steel plate, an electromagnetic soft iron, and a centast. (3) The magnetic core according to claim 1, wherein the magnetic piece is made of ferrite. (41) A magnetic core according to claim 1, wherein the m pieces of magnetic material are formed by tilting a composite magnetic material in which powder or pieces of magnetic material are dispersed in a synthetic resin. ” 2. The entire sentence on page 2, line 10 of the same section above will be deleted and the following sentence will be inserted. "The steresis loss per cycle W/
h is the frequency f.'' 3, +1 on page 3, line 1 of the same box) f! We will correct formula 5 as follows. 4. “At least” comes after “our” on page 6, line 5 of the same page.
I will insert. 5. In the same section, page 7, line 5, "25-35" will be corrected to "25". 6. Delete the entire text of line 9 on the same page as above and insert the following sentence. "Water cooling after the gun, heat treatment to reduce so-called high-frequency iron loss" 7. Figure 1 of the attached drawings has been corrected and edited as shown in the attached sheet. Agent Patent Attorney Ishi 1) Choshichi

Claims (1)

[Claims] (1) A laminated magnetic core formed of a thin magnetic material plate with high magnetic permeability and having an open magnetic path surface such as a cut surface in a part, and a laminated magnetic core that is arranged in contact with the open magnetic path surface and parallel to the open magnetic path surface. A piece of magnetic material whose opposing end surface is an uncut surface and has good electrical resistance and magnetic permeability! lll
A magnetic core. 1211JfJ S self-layered magnetic core body, amorphous magnetic material,
Claim 1: Formed in one building among permanent, 0i, silicon steel plate, electromagnetic soft iron, and Centast.
Magnetic core described in section. 131. The magnetic core according to claim 1, wherein the self-magnetic body piece is made of ferrite. A magnetic core according to claim 1, which is formed of a composite magnetic material dispersed in a synthetic resin.