JPH06120044A - Low-noise transformer core - Google Patents
Low-noise transformer coreInfo
- Publication number
- JPH06120044A JPH06120044A JP3085571A JP8557191A JPH06120044A JP H06120044 A JPH06120044 A JP H06120044A JP 3085571 A JP3085571 A JP 3085571A JP 8557191 A JP8557191 A JP 8557191A JP H06120044 A JPH06120044 A JP H06120044A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- core
- iron core
- flux density
- permeability
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F3/00—Cores, Yokes, or armatures
- H01F3/10—Composite arrangements of magnetic circuits
- H01F2003/106—Magnetic circuits using combinations of different magnetic materials
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は変圧器鉄心の改良に関
し、さらに詳しくはその騒音値を低減する手法に関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvement of a transformer core, and more particularly to a method of reducing its noise value.
【０００２】[0002]
【従来の技術】一般の変圧器の鉄心５は、図３に示すよ
うに磁性材料を環状の閉じた形状にして製作される。こ
れを実際に使用する場合、鉄心内の磁束線３は図３の破
線で示すように、鉄心の外周あるいは内周とほぼ平行と
なるように位置する。すなわち、内周部と外周部の間で
は磁束線のやりとりはないため、内周部と外周部の磁気
回路は互いに独立している、すなわち分離して考えるこ
とができる。ところで、磁気回路の磁気抵抗は次の第１
式で表される。 Ｒ＝Ｌ／（μ・Ｓ） …………… （１） Ｒ：磁気抵抗 Ｌ：磁気回路の長さ（磁路長） μ：材料の透磁率 Ｓ：鉄心の断面積 磁気抵抗Ｒは、磁気回路の長さＬに比例するため、鉄心
内周部の磁気抵抗は外周部の磁気抵抗よりも低くなる。
従って、内周部の磁束密度は外周部の磁束密度よりも高
くなる。一般に、磁束密度−磁歪曲線は図４のような傾
向を示す。ここでの磁歪は、磁性材料が磁化の過程で最
も伸長した時点と収縮した時点での長さの差を示す。こ
の曲線の接線の傾きは、ほぼ全域にわたって単調増加す
る。2. Description of the Related Art An iron core 5 of a general transformer is manufactured by forming a magnetic material into an annular closed shape as shown in FIG. When this is actually used, the magnetic flux lines 3 in the iron core are positioned so as to be substantially parallel to the outer circumference or the inner circumference of the iron core, as shown by the broken line in FIG. That is, since there is no exchange of magnetic flux lines between the inner peripheral portion and the outer peripheral portion, the magnetic circuits of the inner peripheral portion and the outer peripheral portion can be considered independent of each other, that is, can be considered separately. By the way, the magnetic resistance of the magnetic circuit is
It is represented by a formula. R = L / (μ · S) (1) R: Magnetic resistance L: Length of magnetic circuit (magnetic path length) μ: Permeability of material S: Cross-sectional area of iron core Magnetic resistance R is Since it is proportional to the length L of the magnetic circuit, the magnetic resistance of the inner peripheral portion of the iron core becomes lower than that of the outer peripheral portion.
Therefore, the magnetic flux density of the inner peripheral portion becomes higher than the magnetic flux density of the outer peripheral portion. In general, the magnetic flux density-magnetostriction curve shows a tendency as shown in FIG. The magnetostriction here indicates a difference in length between the time when the magnetic material is most expanded and the time when the magnetic material is contracted during the magnetization process. The tangent slope of this curve monotonically increases over almost the entire area.
【０００３】ここで、鉄心内の磁束密度の不均一が、鉄
心の平均磁歪を増加させる現象を説明する。問題を単純
化するために、鉄心を内周部と外周部に二分割し、各部
分内で平均した磁気抵抗値を用いて検討する。それぞれ
の磁気回路の断面積は等しいものとする。外周部の磁束
密度をＢ１、内周部の磁束密度をＢ２とすると、前述の
ようにＢ１＜Ｂ２となる。鉄心全体で見たときの磁束密
度Ｂｔは次の第２式で表される。 Ｂｔ＝（Ｂ１＋Ｂ２）／２ …………… （２） この時の磁歪は図５から求められる。すなわちこの図か
ら、次の第３式が求められる。 λｔ＜λｂ＝（λ１＋λ２）／２ …………… （３） λｔ：磁束密度がＢｔのときの磁歪値 λｂ：鉄心の平均磁歪値 λ１，λ２：外周部，内周部での磁歪値 鉄心内の磁束密度が場所によらず一定であればその値は
Ｂｔとなるので磁歪はλｔとなるが、内周部と外周部で
磁束密度に差がある場合はλｂとなり、均一な場合より
も平均の磁歪値が高いことが分かる。Here, a phenomenon in which the non-uniformity of the magnetic flux density in the iron core increases the average magnetostriction of the iron core will be described. In order to simplify the problem, the core is divided into two parts, the inner part and the outer part, and the magnetic resistance value averaged in each part is used for the study. It is assumed that the magnetic circuits have the same cross-sectional area. Assuming that the magnetic flux density of the outer peripheral portion is B1 and the magnetic flux density of the inner peripheral portion is B2, B1 <B2 as described above. The magnetic flux density Bt of the entire iron core is expressed by the following second equation. Bt = (B1 + B2) / 2 (2) Magnetostriction at this time can be obtained from FIG. That is, the following third equation is obtained from this figure. λt <λb = (λ1 + λ2) / 2 (3) λt: Magnetostrictive value when the magnetic flux density is Bt λb: Average magnetostrictive value of the iron core λ1, λ2: Magnetostrictive value at the outer and inner circumferences of the iron core If the magnetic flux density inside is constant regardless of the location, the value is Bt, so the magnetostriction is λt. It can be seen that the average magnetostriction value is high.
【０００４】[0004]
【発明が解決しようとする課題】以上のように、鉄心の
内周と外周に、の磁路長差による磁気抵抗の差が有る場
合は、差がない場合よりも磁歪が大きくなる。この発明
は、鉄心の内周と外周の磁気抵抗の差をなくした低騒音
変圧器鉄心を目的とする。As described above, when there is a difference in magnetic resistance due to the difference in magnetic path length between the inner circumference and the outer circumference of the iron core, the magnetostriction becomes larger than when there is no difference. An object of the present invention is to provide a low noise transformer iron core in which the difference in magnetic resistance between the inner circumference and the outer circumference of the iron core is eliminated.
【０００５】[0005]
【課題を解決するための手段】第１式より、内周と外周
の磁気抵抗の差をなくすためにはそれぞれの位置で材料
の透磁率を変更すれば良い。透磁率μを連続的に変化さ
せる場合には、次の第４式で決定することができる。 μ＝（ｋ・Ｌ） …………… （４） Ｌ：磁道長 ｋ：任意定数（透磁率の変化可能範囲を考慮して決定） 透磁率の連続的変化が困難な場合でも、鉄心を数分割し
て考えればよい。鉄心断面を内周部と外周部に二等分し
た場合を考えると、次の第５式が成り立つように材料の
μを選べば良い。 μ１／Ｌ１＝μ２／Ｌ２ …………… （５） μ１，μ２：外周部，内周部の材料の透磁率 Ｌ１，Ｌ２：外周部，内周部の平均磁路長 なお、磁性材料の磁歪は励磁磁束密度の最大値で決まる
ので、第４，５式のμは最大磁束密度のときの値を用い
れば良い。According to the first equation, in order to eliminate the difference in magnetic resistance between the inner circumference and the outer circumference, the magnetic permeability of the material may be changed at each position. When the magnetic permeability μ is continuously changed, it can be determined by the following fourth formula. μ = (k · L) (4) L: Magnetic path length k: Arbitrary constant (determined in consideration of the changeable range of magnetic permeability) Even if it is difficult to continuously change the magnetic permeability, It can be divided into several parts. Considering the case where the cross section of the core is divided into the inner peripheral portion and the outer peripheral portion, it is sufficient to select μ of the material so that the following fifth equation is satisfied. μ1 / L1 = μ2 / L2 (5) μ1, μ2: Permeability of material in outer and inner circumferences L1, L2: Average magnetic path length in outer and inner circumferences Since the magnetostriction is determined by the maximum value of the magnetic flux density for excitation, the value of μ at the maximum magnetic flux density may be used as μ in the expressions 4 and 5.
【０００６】磁性材料の透磁率を変化させる方法の例と
して、磁気回路の一部分にギャップを設ける方法があ
る。また、けい素鋼板の場合では、レーザービーム照射
で透磁率を下げる方法等が考えられる。As an example of a method of changing the magnetic permeability of a magnetic material, there is a method of providing a gap in a part of a magnetic circuit. In the case of a silicon steel sheet, a method of lowering the magnetic permeability by laser beam irradiation can be considered.
【０００７】[0007]
【作用】この手法を用いれば、鉄心の内周部と外周部の
間の磁束密度の差をなくすことができ、磁歪を低下させ
ることができるので、騒音低減が可能である。By using this method, the difference in magnetic flux density between the inner peripheral portion and the outer peripheral portion of the iron core can be eliminated and the magnetostriction can be reduced, so that noise can be reduced.
【０００８】[0008]
【実施例】単相積み鉄心変圧器で本発明の効果を検証し
た。透磁率を変更するために、方向性電磁鋼板にレーザ
ービームを照射する手法を用いた。レーザー照射によっ
て透磁率は低下するが、その低下量はビームエネルギー
と比例関係にある。EXAMPLE The effect of the present invention was verified with a single-phase stacked core transformer. A method of irradiating a grain-oriented electrical steel sheet with a laser beam was used to change the magnetic permeability. Although the magnetic permeability is decreased by laser irradiation, the amount of decrease is proportional to the beam energy.
【０００９】図１はその実施例を示すものである。鉄心
寸法は、幅４５０mm、高さ７５０mm、鋼板幅１５０mmと
した。この外周部を領域１、内周部を領域２とし、その
境界線は鋼板の中心線とした。領域１と２の平均磁路長
は、それぞれ２１００mm、１５００mmである。領域１に
２．５mJ／mm2 のエネルギーのレーザービームを照射す
ると、磁界−磁束密度特性は図２の条件１の曲線とな
る。FIG. 1 shows an embodiment thereof. The iron core had a width of 450 mm, a height of 750 mm, and a steel plate width of 150 mm. The outer peripheral portion was defined as the area 1 and the inner peripheral portion was defined as the area 2, and the boundary line was defined as the center line of the steel sheet. The average magnetic path lengths of the regions 1 and 2 are 2100 mm and 1500 mm, respectively. When the region 1 is irradiated with the laser beam having the energy of 2.5 mJ / mm 2 , the magnetic field-magnetic flux density characteristic becomes the curve of the condition 1 in FIG.
【００１０】鉄心の設計磁束密度を１．５Ｔとすると、
その時の透磁率は、０．０５２Ｈ／ｍである。第５式を
変形した第６式から、内周部の透磁率を求める。 μ２＝（λ１・Ｌ２）／Ｌ１ ＝（０．０５２・１５００）／２１００ ＝０．０３７（Ｈ／ｍ） …………… （６） 領域２でこの透磁率を得るためには、ビームエネルギー
４．０mJ／mm2 が最適であった。そのときの磁界−磁束
密度曲線を、図２の条件２に示す。この鉄心は、全体に
均一なエネルギーのレーザー照射を行った鉄心よりも騒
音が２．１db（Ａ）低く、騒音低減効果が確認された。If the design magnetic flux density of the iron core is 1.5T,
The magnetic permeability at that time is 0.052 H / m. The magnetic permeability of the inner peripheral portion is obtained from the sixth equation obtained by modifying the fifth equation. μ2 = (λ1 · L2) / L1 = (0.052 · 1500) /2100=0.037 (H / m) (6) In order to obtain this permeability in the region 2, the beam energy is required. The optimum value was 4.0 mJ / mm 2 . The magnetic field-magnetic flux density curve at that time is shown in Condition 2 of FIG. This iron core has a noise level of 2.1 db (A) lower than that of the iron core irradiated with a laser beam having uniform energy, and the noise reduction effect was confirmed.
【００１１】[0011]
【発明の効果】鉄心内周部と外周部の磁性材料の透磁率
を、内周部が低くなるようにすることで、鉄心内の磁束
密度の不均一が解消し、磁歪を減少させることで騒音を
低減することができる。EFFECTS OF THE INVENTION By making the magnetic permeability of the magnetic material in the inner and outer peripheral portions of the iron core lower in the inner peripheral portion, unevenness of magnetic flux density in the iron core is eliminated, and magnetostriction is reduced. Noise can be reduced.
【図１】本発明の実施例として用いた鉄心の説明図であ
る。FIG. 1 is an explanatory diagram of an iron core used as an example of the present invention.
【図２】実施例で用いた磁界−磁束密度曲線の図表であ
る。FIG. 2 is a chart of a magnetic field-magnetic flux density curve used in Examples.
【図３】変圧器鉄心の正面図である。FIG. 3 is a front view of a transformer core.
【図４】磁束密度−磁歪曲線の図表である。FIG. 4 is a diagram of a magnetic flux density-magnetostriction curve.
【図５】磁束密度−磁歪曲線の拡大図表である。FIG. 5 is an enlarged chart of a magnetic flux density-magnetostriction curve.
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【手続補正書】[Procedure amendment]
【提出日】平成３年５月３０日[Submission date] May 30, 1991
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００５[Name of item to be corrected] 0005
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【０００５】[0005]
【課題を解決するための手段】第１式より、内周と外周
の磁気抵抗の差をなくすためにはそれぞれの位置で材料
の透磁率を変更すれば良い。透磁率μを連続的に変化さ
せる場合には、次の第４式で決定することができる。 μ＝（ｋ・Ｌ） …………… （４） Ｌ：磁路長 ｋ：任意定数（透磁率の変化可能範囲を考慮して決定） 透磁率の連続的変化が困難な場合でも、鉄心を数分割し
て考えればよい。鉄心断面を内周部と外周部に二等分し
た場合を考えると、次の第５式が成り立つように材料の
μを選べば良い。 μ１／Ｌ１＝μ２／Ｌ２ …………… （５） μ１，μ２：外周部，内周部の材料の透磁率 Ｌ１，Ｌ２：外周部，内周部の平均磁路長 なお、磁性材料の磁歪は励磁磁束密度の最大値で決まる
ので、第４，５式のμは最大磁束密度のときの値を用い
れば良い。According to the first equation, in order to eliminate the difference in magnetic resistance between the inner circumference and the outer circumference, the magnetic permeability of the material may be changed at each position. When the magnetic permeability μ is continuously changed, it can be determined by the following fourth formula. μ = (kL) …………… (4) L: Magnetic path length k: Arbitrary constant (determined in consideration of the changeable range of permeability) Even if it is difficult to continuously change the permeability, the iron core Should be divided into several parts. Considering the case where the cross section of the core is divided into the inner peripheral portion and the outer peripheral portion, it is sufficient to select μ of the material so that the following fifth equation is satisfied. μ1 / L1 = μ2 / L2 (5) μ1, μ2: Permeability of material in outer and inner circumferences L1, L2: Average magnetic path length in outer and inner circumferences Since the magnetostriction is determined by the maximum value of the magnetic flux density for excitation, the value of μ at the maximum magnetic flux density may be used as μ in the expressions 4 and 5.
【手続補正２】[Procedure Amendment 2]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１０[Correction target item name] 0010
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１０】鉄心の設計磁束密度を１．５Ｔとすると、
その時の透磁率は、０．０５２Ｈ／ｍである。第５式を
変形した第６式から、内周部の透磁率を求める。 μ２＝（μ１・Ｌ２）／Ｌ１ ＝（０．０５２・１５００）／２１００ ＝０．０３７（Ｈ／ｍ） …………… （６） 領域２でこの透磁率を得るためには、ビームエネルギー
４．０mJ／mm2 が最適であった。そのときの磁界−磁束
密度曲線を、図２の条件２に示す。この鉄心は、全体に
均一なエネルギーのレーザー照射を行った鉄心よりも騒
音が２．１db（Ａ）低く、騒音低減効果が確認された。If the design magnetic flux density of the iron core is 1.5T,
The magnetic permeability at that time is 0.052 H / m. The magnetic permeability of the inner peripheral portion is obtained from the sixth equation obtained by modifying the fifth equation. μ2 = (μ1 · L2) / L1 = (0.052 · 1500) /2100=0.037 (H / m) (6) In order to obtain this permeability in the region 2, the beam energy is required. The optimum value was 4.0 mJ / mm 2 . The magnetic field-magnetic flux density curve at that time is shown in Condition 2 of FIG. This iron core has a noise level of 2.1 db (A) lower than that of the iron core irradiated with a laser beam having uniform energy, and the noise reduction effect was confirmed.
Claims (1)
よりも低い材料を配設したことを特徴とする変圧器鉄
心。1. A transformer core, wherein a material having a magnetic permeability of an inner peripheral portion lower than that of an outer peripheral portion is arranged.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3085571A JPH06120044A (en) | 1991-04-17 | 1991-04-17 | Low-noise transformer core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3085571A JPH06120044A (en) | 1991-04-17 | 1991-04-17 | Low-noise transformer core |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06120044A true JPH06120044A (en) | 1994-04-28 |
Family
ID=13862502
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3085571A Withdrawn JPH06120044A (en) | 1991-04-17 | 1991-04-17 | Low-noise transformer core |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06120044A (en) |
Cited By (10)
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|---|---|---|---|---|
| JP2007180135A (en) * | 2005-12-27 | 2007-07-12 | Hitachi Industrial Equipment Systems Co Ltd | Transformer |
| US7675398B2 (en) | 2005-07-08 | 2010-03-09 | Hitachi Industrial Equipment Systems Co., Ltd. | Iron core for stationary apparatus and stationary apparatus |
| WO2010026898A1 (en) | 2008-09-03 | 2010-03-11 | 株式会社日立産機システム | Wound iron core for static apparatus, amorphous transformer and coil winding frame for transformer |
| JP2010087536A (en) * | 2005-07-08 | 2010-04-15 | Hitachi Industrial Equipment Systems Co Ltd | Three-phase tripod iron core |
| JP2010114170A (en) * | 2008-11-05 | 2010-05-20 | Hitachi Industrial Equipment Systems Co Ltd | Iron core for static apparatus |
| JP2010263233A (en) * | 2010-07-12 | 2010-11-18 | Hitachi Industrial Equipment Systems Co Ltd | Transformer |
| JP2011108981A (en) * | 2009-11-20 | 2011-06-02 | Denso Corp | Reactor |
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| JP2020150089A (en) * | 2019-03-12 | 2020-09-17 | 日本製鉄株式会社 | Iron core, method of manufacturing wound iron core, method of manufacturing laminated iron core and method of manufacturing electromagnetic steel sheet for iron core |
| JP2021163943A (en) * | 2020-04-03 | 2021-10-11 | 日本製鉄株式会社 | Winding iron core, manufacturing method of winding iron core, and winding iron core manufacturing device |
-
1991
- 1991-04-17 JP JP3085571A patent/JPH06120044A/en not_active Withdrawn
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|---|---|---|---|---|
| JP2012169666A (en) * | 2005-07-08 | 2012-09-06 | Hitachi Industrial Equipment Systems Co Ltd | Wound iron core for static apparatus, and static apparatus with the same |
| JP2010087536A (en) * | 2005-07-08 | 2010-04-15 | Hitachi Industrial Equipment Systems Co Ltd | Three-phase tripod iron core |
| EP1742232A3 (en) * | 2005-07-08 | 2011-09-21 | Hitachi Industrial Equipment Systems Co., Ltd. | Iron core for stationary apparatus and stationary apparatus |
| US7675398B2 (en) | 2005-07-08 | 2010-03-09 | Hitachi Industrial Equipment Systems Co., Ltd. | Iron core for stationary apparatus and stationary apparatus |
| US8258912B2 (en) | 2005-07-08 | 2012-09-04 | Hitachi Industrial Equipment Systems Co., Ltd. | Iron core for stationary apparatus and stationary apparatus |
| JP2007180135A (en) * | 2005-12-27 | 2007-07-12 | Hitachi Industrial Equipment Systems Co Ltd | Transformer |
| WO2010026898A1 (en) | 2008-09-03 | 2010-03-11 | 株式会社日立産機システム | Wound iron core for static apparatus, amorphous transformer and coil winding frame for transformer |
| US9601256B2 (en) | 2008-09-03 | 2017-03-21 | Hitachi Industrial Equipment Systems Co., Ltd. | Wound iron core for static apparatus, amorphous transformer and coil winding frame for transformer |
| US9013263B2 (en) | 2008-09-03 | 2015-04-21 | Hitachi Industrial Equipment Systems Co., Ltd. | Wound iron core for static apparatus, amorphous transformer and coil winding frame for transformer |
| JP2010114170A (en) * | 2008-11-05 | 2010-05-20 | Hitachi Industrial Equipment Systems Co Ltd | Iron core for static apparatus |
| JP2011108981A (en) * | 2009-11-20 | 2011-06-02 | Denso Corp | Reactor |
| JP2010263233A (en) * | 2010-07-12 | 2010-11-18 | Hitachi Industrial Equipment Systems Co Ltd | Transformer |
| CN104124040A (en) * | 2013-04-25 | 2014-10-29 | 台达电子工业股份有限公司 | Magnetic core and magnetic element applying same |
| JP2020150089A (en) * | 2019-03-12 | 2020-09-17 | 日本製鉄株式会社 | Iron core, method of manufacturing wound iron core, method of manufacturing laminated iron core and method of manufacturing electromagnetic steel sheet for iron core |
| JP2021163943A (en) * | 2020-04-03 | 2021-10-11 | 日本製鉄株式会社 | Winding iron core, manufacturing method of winding iron core, and winding iron core manufacturing device |
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