JP5716330B2 - Evaluation method of electrical steel sheet for laminated iron core - Google Patents
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- 229910000976 Electrical steel Inorganic materials 0.000 title claims description 38
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 title claims description 33
- 238000011156 evaluation Methods 0.000 title claims description 11
- 238000001228 spectrum Methods 0.000 claims description 54
- 229910000831 Steel Inorganic materials 0.000 claims description 53
- 239000010959 steel Substances 0.000 claims description 53
- 230000005284 excitation Effects 0.000 claims description 44
- 238000001845 vibrational spectrum Methods 0.000 claims description 43
- 238000000034 method Methods 0.000 claims description 15
- 238000010030 laminating Methods 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 4
- 239000011162 core material Substances 0.000 description 64
- 238000005259 measurement Methods 0.000 description 19
- 238000004364 calculation method Methods 0.000 description 7
- 238000012821 model calculation Methods 0.000 description 5
- 230000003595 spectral effect Effects 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 229920001342 Bakelite® Polymers 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 2
- 239000004637 bakelite Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 150000002505 iron Chemical group 0.000 description 2
- 241000282412 Homo Species 0.000 description 1
- 229910000576 Laminated steel Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
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- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Soft Magnetic Materials (AREA)
- Manufacturing Cores, Coils, And Magnets (AREA)
Description
本発明は、積層して積層体鉄心（積層構造の鉄心）を製造するための電磁鋼板の評価方法に関するものである。 The present invention relates to a method for evaluating an electromagnetic steel sheet for producing a laminated core (laminated structure core) by laminating.
電磁鋼板は積層されて、変圧器の鉄心（積層体鉄心）として用いられるが、励磁すると磁歪や磁力の作用によって振動が生じ、騒音源となる。騒音の小さい変圧器（積層体鉄心）を製造する場合、一般に磁歪の小さい電磁鋼板を鉄心材料として使用する。しかし、磁歪の小さい電磁鋼板を使用しているにもかかわらず、変圧器の騒音が要求仕様を満たせない場合がある。 Magnetic steel sheets are laminated and used as an iron core (laminate iron core) of a transformer. When excited, vibrations are generated by the action of magnetostriction and magnetic force, and become a noise source. When manufacturing a transformer (laminated iron core) with low noise, generally an electromagnetic steel sheet with a small magnetostriction is used as the iron core material. However, there are cases where the noise of the transformer cannot meet the required specifications even though the electromagnetic steel sheet having a small magnetostriction is used.
その原因の多くは、変圧器鉄心（積層体鉄心）の固有振動と電磁鋼板の磁歪振動の共振現象である。このため、変圧器鉄心（積層体鉄心）の固有振動数に着目して変圧器を設計する方法が検討されてきた。 Many of the causes are resonance phenomena of the natural vibration of the transformer core (laminated core) and the magnetostrictive vibration of the electrical steel sheet. For this reason, methods for designing transformers have been studied by paying attention to the natural frequency of the transformer core (laminated core).
もし、励磁周波数のＮ次高調波と固有振動が共振する場合には、共振を回避するように積層体鉄心の剛性に関するパラメータを変更することになる。すなわち、積層体鉄心の固定条件を調整あるいは再設計、あるいは積層枚数を変更する。 If the Nth harmonic of the excitation frequency and the natural vibration resonate, the parameter relating to the rigidity of the laminated core is changed so as to avoid the resonance. That is, the fixing condition of the laminated core is adjusted or redesigned, or the number of laminated layers is changed.
なお、積層体鉄心の固有振動数を測定する方法については、例えば特許文献１に記載されている。励磁周波数を段階的に変化させて、その際に積層体鉄心が発生する騒音を測定することで、積層体鉄心の固有振動数を知るものである。 In addition, about the method of measuring the natural frequency of a laminated body core, it describes in patent document 1, for example. The natural frequency of the laminated core is known by changing the excitation frequency stepwise and measuring the noise generated by the laminated core at that time.
しかしながら、電磁鋼板を積層した積層体鉄心は複雑な構造物であり、騒音の対象となりうる５０〜２００００Ｈｚの周波数帯域に無数の固有振動数を有する。一般に、複数の固有振動数を有する構造物の特定の固有振動数のみを変化させることは困難であり、剛性を変化させると固有振動数全体がシフトする。このため、上記のように剛性を変化させる方法では、ある固有振動数とＮ次高調波との共振を回避させても、別の固有振動数がＮ次高調波あるいはＭ次高調波とあらたに共振する可能性が極めて高い。そして、そもそも現実の変圧器の設計では、積層体鉄心の固有振動以外の仕様もあるため、このような設計を実施することは困難である。 However, a laminated iron core in which electromagnetic steel sheets are laminated is a complex structure and has an infinite number of natural frequencies in a frequency band of 50 to 20000 Hz that can be a target of noise. In general, it is difficult to change only a specific natural frequency of a structure having a plurality of natural frequencies. When the rigidity is changed, the entire natural frequency is shifted. For this reason, in the method of changing the rigidity as described above, even if resonance between a certain natural frequency and the Nth harmonic is avoided, another natural frequency is newly added as the Nth harmonic or the Mth harmonic. Very likely to resonate. In the first place, in the actual transformer design, there are specifications other than the natural vibration of the laminated iron core, so it is difficult to implement such a design.
さらに、変圧器においては積層体鉄心の質量が占める割合が支配的であり、積層体鉄心の振動周波数スペクトルと変圧器の外殻構造すなわちタンクの振動周波数スペクトルがほぼ一致するケースが多い。すなわち、積層体鉄心による強制振動が多い。強制振動成分が支配的であって、共振振動成分が相対的に小さいと、固有振動数の変化による共振回避の効果は小さい。 Furthermore, in the transformer, the ratio of the mass of the laminated core is dominant, and the vibration frequency spectrum of the laminated core and the outer shell structure of the transformer, that is, the vibration frequency spectrum of the tank are almost the same. That is, there are many forced vibrations by the laminated core. If the forced vibration component is dominant and the resonance vibration component is relatively small, the effect of avoiding resonance by the change of the natural frequency is small.
以上述べたように、変圧器の低騒音化・低振動化のためには積層体鉄心そのものの振動を低減する必要がある。 As described above, it is necessary to reduce the vibration of the laminated core itself in order to reduce the noise and vibration of the transformer.
積層体鉄心の振動を低減するためには、電磁鋼板単板の磁歪が小さくなれば良い。このため、単板の磁歪が小さくなるような電磁鋼板の開発が電磁鋼板メーカー各社で研究開発が進められてきた。近年、極めて磁歪特性の優れた低磁歪の電磁鋼板が市販されており、この技術開発の方向性は一定の成果をあげている。 In order to reduce the vibration of the laminated iron core, it is sufficient that the magnetostriction of the electromagnetic steel sheet single plate is reduced. For this reason, research and development has been carried out by electrical steel sheet manufacturers to develop electrical steel sheets that reduce the magnetostriction of a single sheet. In recent years, low magnetostrictive electrical steel sheets with extremely excellent magnetostrictive properties have been marketed, and the direction of this technological development has achieved certain results.
ところで、人間の耳の感度には周波数特性があると言われており、騒音はその周波数によって人間が感じる不快感は異なる。このため変圧器騒音の問題に取り組む際には周波数スペクトル特性を無視することはできない。 By the way, it is said that the sensitivity of the human ear has frequency characteristics, and the discomfort felt by humans differs depending on the frequency of noise. For this reason, frequency spectrum characteristics cannot be ignored when tackling the problem of transformer noise.
先に述べたように、積層体鉄心の励磁振動周波数スペクトル特性が変圧器の騒音周波数スペクトル特性に一致することは多い。一方、電磁鋼板単板の磁歪振動周波数スペクトル特性が積層体鉄心の励磁振動周波数スペクトル特性に一致することは殆ど無い。このメカニズムを考察すると、積層体鉄心は電磁鋼板単板を積層して構成するため、各層間の摩擦や単板端部同士の接触といった機械的に非線形な振動現象が生じていると考えられる。さらに、磁歪方向は面内方向であるが、複数の電磁鋼板が積層され締結されることで、結果として面外方向の振動現象が生じることも多い。このように電磁鋼板単板では一方向の磁歪現象であるが、積層体鉄心に組み上げられると極めて複雑な振動現象となっている。 As described above, the excitation vibration frequency spectrum characteristics of the laminated core often coincide with the noise frequency spectrum characteristics of the transformer. On the other hand, the magnetostrictive vibration frequency spectrum characteristics of the single electromagnetic steel sheet plate hardly coincide with the excitation vibration frequency spectrum characteristics of the laminated iron core. Considering this mechanism, since the laminated iron core is formed by laminating magnetic steel sheet single plates, it is considered that mechanically non-linear vibration phenomena such as friction between layers and contact between end portions of the single plate are generated. Further, although the magnetostriction direction is the in-plane direction, a plurality of electromagnetic steel sheets are stacked and fastened, and as a result, an out-of-plane vibration phenomenon often occurs. As described above, although the electromagnetic steel sheet has a unidirectional magnetostriction phenomenon, it is a very complicated vibration phenomenon when assembled on a laminated core.
よって、低磁歪の電磁鋼板を開発したとしても、積層体鉄心に組み上げて励磁させると単板での磁歪の周波数特性とは全く無関係な傾向を示す。ある特定の周波数で騒音が大きくなり、騒音オーバーオール値としては悪化する。このような現象のため、単純に磁歪が小さい電磁鋼板を開発するだけでは騒音が小さくならず、電磁鋼板の開発を難しくしている。 Therefore, even if a low magnetostrictive electrical steel sheet is developed, when it is assembled into a laminated core and excited, it tends to be completely unrelated to the frequency characteristics of magnetostriction in a single plate. Noise increases at a specific frequency, and the noise overall value deteriorates. Because of such a phenomenon, simply developing an electromagnetic steel sheet with a small magnetostriction does not reduce noise, making it difficult to develop an electromagnetic steel sheet.
そこで、新型の電磁鋼板が開発された場合には、それを用いて積層体鉄心を組み上げ、振動・騒音測定を実施してみて初めて評価される。 Therefore, when a new type of electrical steel sheet is developed, it is evaluated only when a laminated core is assembled using the steel sheet and vibration and noise measurement is performed.
すなわち、積層体鉄心の励磁振動周波数スペクトルと電磁鋼板の磁歪振動周波数スペクトルとの相関が不明確なため、電磁鋼板の周波数特性（磁歪振動周波数スペクトル特性）をどのようにすれば積層体鉄心では理想的なのかの指針が無く、試行錯誤的な実験の繰り返しとなってしまう。 In other words, since the correlation between the excitation vibration frequency spectrum of the laminated iron core and the magnetostrictive vibration frequency spectrum of the magnetic steel sheet is unclear, what is the ideal frequency characteristic of the magnetic steel sheet for the laminated iron core? There is no guideline on whether or not it is true, and trial and error experiments are repeated.
本発明は、上記のような事情に鑑みてなされたものであり、積層して積層体鉄心を製造するための電磁鋼板を評価する方法として、試行錯誤的な実験を繰り返すことなく、積層体鉄心となった状態での振動・騒音が小さくなるような周波数特性（磁歪振動周波数スペクトル特性）を備えた電磁鋼板を得るための電磁鋼板の評価方法を提供することを目的とするものである。 The present invention has been made in view of the circumstances as described above, and as a method of evaluating an electromagnetic steel sheet for producing a laminated iron core by laminating, a laminated iron core without repeating trial and error experiments. It is an object of the present invention to provide a method for evaluating an electrical steel sheet for obtaining an electrical steel sheet having frequency characteristics (magnetostrictive vibration frequency spectrum characteristics) that can reduce vibration and noise in such a state.
前記課題を解決するために、本発明は以下の特徴を有している。 In order to solve the above problems, the present invention has the following features.
［１］積層して積層体鉄心を製造するための電磁鋼板を評価する方法であって、予め定められた枚数の電磁鋼板を予め定められた状態で締結して積層体鉄心となった状態の振動スペクトルを予測するに際して、前記積層体鉄心を周波数２ｆ×ｋＨｚの正弦波（ｆ：積層体鉄心励磁周波数、ｋ：整数＝１、２、３、・・・）別に機械加振し、その加振周波数２ｆ×ｋ別に２ｆ×ｍ（ｍ＝ｋ、２ｋ、３ｋ、・・・）の周波数で積層体鉄心振動の周波数応答を測定するとともに、別途、単板状態の前記電磁鋼板に発生する磁歪振動周波数スペクトルを測定して得られる周波数２ｆ×ｋ毎の磁歪振動強度を周波数２ｆ×ｋ別の重みデータ列として設定しておき、前記積層体鉄心振動の周波数応答データと前記重みデータ列を用いて、加振周波数２ｆ×ｋ別の周波数応答データの成分同士の重み付き線形和を計算し、この重み付き線形和をもって積層体鉄心を励磁した時の振動スペクトル予測値とし、この振動スペクトル予測値が所定の上限値以下の場合は、当該電磁鋼板は合格と評価し、この振動スペクトル予測値が所定の上限値より大きい場合は、当該電磁鋼板は不合格と評価することを特徴とする電磁鋼板の評価方法。 [1] A method for evaluating an electromagnetic steel sheet for producing a laminated iron core by laminating, wherein a predetermined number of electromagnetic steel sheets are fastened in a predetermined state to form a laminated iron core. in predicting the vibration spectrum, the sine wave of the laminate core frequency 2f × kHz (f: laminate core excitation frequency, k: integer = 1, 2, 3, ...) separately mechanically vibrated, the pressurized vibration frequency 2f × k separately 2f × m (m = k, 2k, 3k, ···) measuring the frequency response of the laminate core vibrations at a frequency of both separately generated in the electromagnetic steel veneer state The magnetostrictive vibration intensity for each frequency 2f × k obtained by measuring the magnetostrictive vibration frequency spectrum is set as a weight data string for each frequency 2f × k, and the frequency response data of the laminated core vibration and the weight data string are set as follows. Use the excitation frequency 2f × k separately The weighted linear sum of the components between the frequency response data is calculated, and a vibration spectrum predicted values when excited laminate core with the weighted linear sum, if the predicted value This vibrational spectrum is equal to or less than a predetermined upper limit value, the electrical steel sheet is evaluated as acceptable if the vibrational spectrum predicted value is larger than a predetermined upper limit value, the evaluation method of the electromagnetic steel the electrical steel sheet, characterized in that the evaluating rejected.
［２］前記振動スペクトル予測値の総和値が所定の上限値以下の場合は、当該電磁鋼板は合格と評価し、前記振動スペクトル予測値の総和値が所定の上限値より大きい場合は、当該電磁鋼板は不合格と評価することを特徴とする前記［１］に記載の電磁鋼板の評価方法。 [2] When the sum total value of the vibration spectrum predicted values is equal to or less than a predetermined upper limit value , the electromagnetic steel sheet is evaluated as passing, and when the sum total value of the vibration spectrum predicted values is greater than the predetermined upper limit value, The method for evaluating an electrical steel sheet according to [1], wherein the steel sheet is evaluated as rejected .
［３］前記振動スペクトル予測値の内、特定の周波数の振動スペクトル予測値が所定の上限値以下の場合は、当該電磁鋼板は合格と評価し、前記振動スペクトル予測値の内、特定の周波数の振動スペクトル予測値が所定の上限値より大きい場合は、当該電磁鋼板は不合格と評価することを特徴とする前記［１］または［２］に記載の電磁鋼板の評価方法。 [3] If the vibration spectrum predicted value of a specific frequency is less than or equal to a predetermined upper limit value among the vibration spectrum predicted values , the electrical steel sheet is evaluated as passing, and the vibration spectrum predicted value has a specific frequency. When the predicted vibration spectrum value is larger than a predetermined upper limit value, the electrical steel sheet is evaluated as rejected . The method for evaluating an electrical steel sheet according to [1] or [2] above.
［４］当該電磁鋼板は不合格と評価された場合は、前記振動スペクトル予測値が所定の上限値以下となるように前記重みデータ列を再設定し、この再設定した重みデータ列が積層体鉄心を構成している電磁鋼板を単板で周波数ｆで励磁した時に周波数２ｆ×ｋの間隔で発生する磁歪スペクトルと考えて、この磁歪スペクトルに相当する周波数特性を有するように、電磁鋼板の組成または／および表面状態を調整することを特徴とする前記［１］〜［３］のいずれかに記載の電磁鋼板の評価方法。
［５］前記２ｆ×ｍ（ｍ＝ｋ、２ｋ、３ｋ、・・・）の周波数に代えて、２ｆ×ｍ（ｍ＝２ｋ、３ｋ、・・・）の周波数で前記積層体鉄心振動の周波数応答を測定し、その２ｆ×ｍ（ｍ＝２ｋ、３ｋ、・・・）の周波数での積層体鉄心振動の周波数応答と前記重みデータ列を用いて、加振周波数２ｆ×ｋ別の周波数応答データの成分同士の重み付き線形和を計算し、この重み付き線形和をもって積層体鉄心を励磁した時の振動スペクトル予測値とすることを特徴とする前記［１］〜［４］のいずれかに記載の電磁鋼板の評価方法。
[4] If the electrical steel sheet is evaluated as rejected, the weight data string is reset so that the predicted vibration spectrum value is equal to or lower than a predetermined upper limit value, and the reset weight data string is the laminate. electromagnetic steel plates constituting the iron core believe magnetostrictive spectrum generated at intervals of the frequency 2f × k when excited at a frequency f in single plate, so as to have a frequency characteristic corresponding to the magnetostrictive spectrum, the composition of the electrical steel sheet or / and evaluation methods of the electromagnetic steel sheet according to any one of [1] to [3], wherein the adjusting the surface state.
[5] The 2f × instead frequency of m (m = k, 2k, 3k, ···), 2f × m (m = 2k, 3k, ···) frequency of the laminate core vibrations at a frequency of The response is measured, and the frequency response of the laminated core vibration at the frequency of 2f × m (m = 2k, 3k,...) And the weight data string are used to determine the frequency response for each excitation frequency 2f × k. Any one of the above [1] to [ 4 ], wherein a weighted linear sum of data components is calculated, and the weighted linear sum is used as a vibration spectrum predicted value when the laminated core is excited. The evaluation method of the magnetic steel sheet described.
［６］前記積層体鉄心励磁周波数ｆは５０Ｈｚまたは６０Ｈｚであることを特徴とする前記［１］〜［５］のいずれかに記載の電磁鋼板の評価方法。 [ 6 ] The method for evaluating an electrical steel sheet according to any one of [1] to [ 5 ], wherein the laminated core excitation frequency f is 50 Hz or 60 Hz.
［７］２ｆ×ｋ≦２４０００Ｈｚであることを特徴とする前記［１］〜［６］のいずれかに記載の電磁鋼板の評価方法。 [ 7 ] 2f × k ≦ 24000 Hz, The method for evaluating an electrical steel sheet according to any one of the above [1] to [ 6 ].
［８］積層体鉄心はＵＶＷの３相形状であって、機械加振を行う際の加振点はＶ脚とヨークの境界であることを特徴とする前記［１］〜［７］のいずれかに記載の電磁鋼板の評価方法。 [ 8 ] Any one of [1] to [ 7 ], wherein the laminated iron core has a UVW three-phase shape, and the excitation point when performing mechanical excitation is a boundary between the V leg and the yoke. An evaluation method for an electromagnetic steel sheet according to claim 1 .
本発明においては、積層して積層体鉄心を製造するための電磁鋼板として、試行錯誤的な実験を繰り返すことなく、積層体鉄心となった状態での振動・騒音が小さくなるような周波数特性（磁歪振動周波数スペクトル特性）を備えた電磁鋼板を得ることができる。 In the present invention, as a magnetic steel sheet for producing a laminated iron core by laminating, frequency characteristics such that vibration and noise in the laminated iron core are reduced without repeating trial and error experiments ( An electrical steel sheet having magnetostrictive vibration frequency spectrum characteristics) can be obtained.
本発明の一実施形態を図面に基づいて説明する。 An embodiment of the present invention will be described with reference to the drawings.
本発明の一実施形態においては、電磁鋼板の磁歪周波数特性（磁歪周波数スペクトル特性）を入力として、当該電磁鋼板を積層した積層体鉄心を励磁した時の振動特性（励磁振動周波数スペクトル特性）を予測する振動モデルを作成しておき、その振動モデルを用いて、積層体鉄心となった状態での振動特性（励磁振動周波数スペクトル特性）が所望の制約条件を満足するようになる磁歪周波数特性（磁歪周波数スペクトル特性）を備えた電磁鋼板を得るようにしている。 In one embodiment of the present invention, a magnetostriction frequency characteristic (magnetostriction frequency spectrum characteristic) of an electromagnetic steel sheet is used as an input, and a vibration characteristic (excitation vibration frequency spectrum characteristic) when a laminated core having the electromagnetic steel sheet laminated is excited is predicted. A vibration model is created, and using that vibration model, the vibration characteristics (excitation vibration frequency spectrum characteristics) in the state of the laminated core satisfy the desired constraints. An electrical steel sheet having frequency spectrum characteristics) is obtained.
まず、図１は、本発明の一実施形態における振動モデルの基本的な考え方を示す図である。 First, FIG. 1 is a diagram showing a basic concept of a vibration model in one embodiment of the present invention.
図１に示すように、この実施形態においては、電磁鋼板を積層した積層体鉄心を励磁した時の振動特性を予測する振動モデルを決定するに際して、積層体鉄心を構成している電磁鋼板を単板状態で周波数ｆ（ここでは５０Ｈｚ）で励磁した時に周波数２ｆ×ｋ（ｋ：整数＝１、２、３、・・・）の間隔で発生する振動スペクトル（磁歪振動周波数スペクトル）に対応させて、積層体鉄心を周波数２ｆ×ｋの正弦波別に単一周波数で機械加振し、その加振周波数２ｆ×ｋ別に２ｆ×ｍ（ｍ＝ｋ、２ｋ、３ｋ、・・・）の周波数（測定周波数１）で積層体鉄心振動の周波数応答を測定するとともに、上記の単板状態の電磁鋼板に発生する磁歪振動周波数スペクトルを予め測定して周波数２ｆ×ｋ毎の磁歪振動強度に基づく重みデータ列Ｗｋ（ｋ：整数＝１、２、３、・・・）を得ておき、前記積層体鉄心振動の加振周波数２ｆ×ｋ別の周波数応答データの成分に、対応する前記周波数２ｆ×ｋ毎の重みＷｋを乗じてから、加振周波数２ｆ×ｋ別に周波数応答データの成分を足し合わせることによって、加振周波数２ｆ×ｋ別の周波数応答データの成分同士の重み付き線形和を計算し、この重み付き線形和をもって積層体鉄心を励磁した時の振動スペクトル予測モデルとしている。 As shown in FIG. 1, in this embodiment, when determining a vibration model for predicting vibration characteristics when a laminated iron core in which electromagnetic steel sheets are laminated is excited, a single electromagnetic steel sheet constituting the laminated iron core is used. Corresponding to a vibration spectrum (magnetostrictive vibration frequency spectrum) generated at intervals of frequency 2f × k (k: integer = 1, 2, 3,...) When excited at a frequency f (here, 50 Hz) in a plate state. The laminated core is mechanically vibrated at a single frequency for each sine wave of frequency 2f × k, and the frequency (measurement) is 2f × m (m = k, 2k, 3k,...) For each of the vibration frequencies 2f × k. The frequency response of the laminated core vibration is measured at frequency 1), and the magnetostriction vibration frequency spectrum generated in the electromagnetic steel sheet in the single plate state is measured in advance, and the weight data string based on the magnetostriction vibration intensity for each frequency 2f × k. Wk (k: integer = 1, 2, 3,...), And the frequency response data component for each excitation frequency 2f × k of the laminated core vibration is multiplied by the corresponding weight Wk for each frequency 2f × k. Then, by adding the components of the frequency response data for each excitation frequency 2f × k, a weighted linear sum of the components of the frequency response data for each excitation frequency 2f × k is calculated. It is a model for predicting the vibration spectrum when the laminated core is excited.
次に、本発明の一実施形態における振動モデルを具体的に説明する。 Next, the vibration model in one embodiment of the present invention will be specifically described.
図２は、本発明の一実施形態おいて機械加振による積層体鉄心振動の周波数応答を測定している状態を示す図である。 FIG. 2 is a diagram illustrating a state in which the frequency response of the laminated core vibration due to mechanical vibration is measured in one embodiment of the present invention.
図２に示すように、ベークライト１２を介してばね１３によって締結力を設定した積層体鉄心（小型モデル）１１に対して、信号発生器２１によって生成された周波数２ｆ×ｋの正弦波（ｆ：５０Ｈｚ、ｋ：整数＝１、２、３、・・・）別に単一周波数で機械的加振力で加振する。なお、加振力はロードセル２３によって測定する。なお、周波数２ｆ×ｋは、人間の可聴上限である２４０００Ｈｚ以下としている。 As shown in FIG. 2, a sine wave (f: f) of a frequency 2f × k generated by a signal generator 21 is applied to a laminated core (small model) 11 whose fastening force is set by a spring 13 via a bakelite 12. 50 Hz, k: integer = 1, 2, 3,...)) Separately, with a single frequency and mechanical excitation force. The excitation force is measured by the load cell 23. The frequency 2f × k is set to 24000 Hz or less, which is the upper limit of human audibility.
そして、振動センサ２４によって変位、速度、加速度を測定し、時系列波形を得る。得られた時系列波形を周波数解析装置２５で周波数解析し、単一周波数２ｆ×ｋに対する周波数応答（応答スペクトル：変位スペクトル、速度スペクトル、加速度スペクトル）を測定し記録する。応答スペクトルの範囲は２０００Ｈｚまでとしている。そして、この応答スペクトルは２ｆ×ｍ（ｍ＝ｋ、２ｋ、３ｋ、・・・）の周波数（測定周波数１）となっている。 Then, displacement, speed, and acceleration are measured by the vibration sensor 24 to obtain a time series waveform. The obtained time series waveform is frequency-analyzed by the frequency analyzer 25, and the frequency response (response spectrum: displacement spectrum, velocity spectrum, acceleration spectrum) with respect to the single frequency 2f × k is measured and recorded. The range of the response spectrum is up to 2000 Hz. This response spectrum has a frequency (measurement frequency 1) of 2f × m (m = k, 2k, 3k,...).
なお、ここで用いる積層体鉄心（小型モデル）１１は、図３に示すように、ＵＶＷの３相形状である。そして、機械加振を行う際の加振点はＶ脚とヨークの境界であり、振動を測定する応答点（振動センサの設置箇所）は第１応答点、第２応答点、第３応答点の３箇所である。この３箇所の平均値または３箇所のいずれかを代表点位置としてその代表位置での値を採用する。 The laminated iron core (small model) 11 used here has a three-phase UVW shape as shown in FIG. The excitation point at the time of mechanical excitation is the boundary between the V leg and the yoke, and the response points for measuring the vibration (locations where the vibration sensor is installed) are the first response point, the second response point, and the third response point. There are three places. The average value of these three locations or the value at the representative location is adopted as any one of the three locations as the representative point location.
そして、この周波数２ｆ×ｋ別の応答スペクトルデータの周波数成分同士の線形和を計算するが、その際に各周波数２ｆ×ｋに対応する重みＷｋを付けて計算する。この計算結果が、この実施形態における積層体鉄心励磁時の振動スペクトル予測モデルによる計算結果ということになる。 Then, the linear sum of the frequency components of the response spectrum data for each frequency 2f × k is calculated. At this time, the weight Wk corresponding to each frequency 2f × k is added. This calculation result is the calculation result by the vibration spectrum prediction model at the time of exciting the laminated core in this embodiment.
ここで、この各周波数２ｆ×ｋに対応する重みＷｋについては、積層体鉄心１１を構成している電磁鋼板の単板状態での磁歪振動周波数特性が予め測定されており、この磁歪振動周波数特性における各周波数２ｆ×ｋの磁歪振動強度から、図４に示すような各周波数２ｆ×ｋ（１００Ｈｚ、２００Ｈｚ、・・・）に対応する重みＷｋが得られている。なお、図４における重みＷｋは、２０００Ｈｚまでのオーバーオール値を１として正規化された値となっている。 Here, for the weights Wk corresponding to the respective frequencies 2f × k, the magnetostriction vibration frequency characteristics in a single plate state of the electromagnetic steel sheets constituting the laminated core 11 are measured in advance, and the magnetostriction vibration frequency characteristics are measured. A weight Wk corresponding to each frequency 2f × k (100 Hz, 200 Hz,...) As shown in FIG. 4 is obtained from the magnetostrictive vibration intensity of each frequency 2f × k. Note that the weight Wk in FIG. 4 is a value normalized with the overall value up to 2000 Hz as 1.
このようにして計算した、この実施形態における積層体鉄心励磁時の振動スペクトル予測モデルによる振動速度スペクトルの計算結果（モデル計算結果）を図５に示す。なお、比較のために、実際に積層体鉄心を励磁した時の振動速度スペクトルの実測結果（励磁測定結果）も記載している。 FIG. 5 shows the calculation result (model calculation result) of the vibration velocity spectrum calculated by the vibration spectrum prediction model at the time of exciting the laminated core in this embodiment. For comparison, an actual measurement result (excitation measurement result) of the vibration velocity spectrum when the laminated core is actually excited is also shown.
この実施形態におけるモデル計算結果によると、基本周波数（２×５０Ｈｚ×１＝１００Ｈｚ）に近い低周波域では実測結果と合致しないが、３００Ｈｚ以上の高周波域では実測結果と良く合致する。 According to the model calculation result in this embodiment, it does not agree with the actual measurement result in the low frequency range close to the fundamental frequency (2 × 50 Hz × 1 = 100 Hz), but well matches the actual measurement result in the high frequency region of 300 Hz or higher.
次に、周波数２ｆ×ｋ別の応答スペクトルデータの周波数成分同士の重み付き線形和を計算するに際して、２ｆ×ｍ（ｍ＝ｋ、２ｋ、３ｋ、・・・）の周波数になっている応答スペクトルデータの内、加振周波数（２ｆ×ｋ）の成分は除いて、２ｆ×ｍ（ｍ＝２ｋ、３ｋ、・・・）の周波数（測定周波数２）の高調波成分のみ残して測定・記録し、その高調波成分を用いて重み付き線形和（振動速度スペクトル）を計算する。 Next, when calculating a weighted linear sum of frequency components of response spectrum data by frequency 2f × k, the response spectrum having a frequency of 2f × m (m = k, 2k, 3k,...). Measure and record only the harmonic component of the frequency (measurement frequency 2) of 2f × m (m = 2k, 3k, ...), excluding the component of the excitation frequency (2f × k). The weighted linear sum (vibration velocity spectrum) is calculated using the harmonic component.
それによる振動速度スペクトルの計算結果（モデル計算結果）を図６に示す。低周波域（２００Ｈｚ）も実測結果と良く合致している。 FIG. 6 shows the vibration speed spectrum calculation result (model calculation result). The low frequency range (200 Hz) also agrees well with the actual measurement results.
なお、このモデル計算結果では、１００Ｈｚにおける振動速度が得られないが、１００Ｈｚは人間の可聴下限以下の周波数であるので、騒音の評価に関しては特に問題ない。 In this model calculation result, the vibration speed at 100 Hz cannot be obtained. However, since 100 Hz is a frequency below the lower limit of human audibility, there is no particular problem with noise evaluation.
ここで、上述の加振周波数（２ｆ×ｋ）、応答測定周波数（２ｆ×ｍ）である測定周波数１、測定周波数２の関係を下記の表１に示す。 Table 1 below shows the relationship between the above-described excitation frequency (2f × k), the measurement frequency 1 that is the response measurement frequency (2f × m), and the measurement frequency 2.
そして、上記のような振動モデルを用いて、加振周波数２ｆ×ｋ別の周波数応答データの成分同士の重み付き線形和を計算し、この重み付き線形和をもって積層体鉄心を励磁した時の振動スペクトル予測値とすることとする。その際に、この振動スペクトル予測値が所定の制約条件を満足するように重みデータ列Ｗｋが再設定されていて、この重みデータ列Ｗｋが積層体鉄心を構成している電磁鋼板を単板状態で周波数ｆで励磁した時に周波数２ｆ×ｋの間隔で発生する磁歪振動周波数スペクトルと考えて、この磁歪振動周波数スペクトル（重みデータ列Ｗｋ）を電磁鋼板が有するようにする。 Then, using the vibration model as described above, the weighted linear sum of the components of the frequency response data for each excitation frequency 2f × k is calculated, and the vibration when the laminate core is excited with this weighted linear sum. Let it be a spectrum prediction value. At that time, the weight data string Wk is reset so that the vibration spectrum predicted value satisfies a predetermined constraint, and the weight steel string Wk constitutes a laminated steel core in a single plate state. The magnetostrictive vibration frequency spectrum (weight data string Wk) is made to have the magnetostrictive vibration frequency spectrum (weight data string Wk) that is considered to be a magnetostriction vibration frequency spectrum generated at an interval of frequency 2f × k when excited at frequency f.
ここで、積層体鉄心の振動スペクトル予測値が満足すべき制約条件としては、例えば、振動スペクトル予測値の総和値が所定の上限値より小さくなっていること、または／および、振動スペクトル予測値の内、特定の周波数のスペクトル値が所定の上限値よりも小さくなっていることである。場合によっては、需要家から要望された条件を制約条件とすることもできる。 Here, as a constraint condition that the vibration spectrum predicted value of the laminated core should satisfy, for example, the total value of the vibration spectrum predicted values is smaller than a predetermined upper limit value, and / or the vibration spectrum predicted value Among them, the spectrum value of a specific frequency is smaller than a predetermined upper limit value. In some cases, a condition requested by a customer can be set as a constraint condition.
そして、積層体鉄心の振動スペクトル予測値が上記の制約条件を満足するような磁歪振動周波数スペクトル（重みデータ列Ｗｋ）を有する電磁鋼板を製造するには、電磁鋼板の組成や表面状態（表面コーティング、表面粗度）を適切に調整することによって行う。 In order to produce an electrical steel sheet having a magnetostriction vibration frequency spectrum (weight data string Wk) such that the predicted vibration spectrum of the laminated iron core satisfies the above-mentioned constraints, the composition and surface state of the electrical steel sheet (surface coating) , Surface roughness) is appropriately adjusted.
その具体例を図７、図８に示す。 Specific examples thereof are shown in FIGS.
図７は、前述の図５において示した、実際に積層体鉄心を励磁した時の振動速度スペクトルの実測結果（励磁測定結果）に対して、その６００Ｈｚのスペクトル成分が大きいので、上記の振動モデルを用いて、６００Ｈｚのスペクトル成分が低下するように重み列Ｗｋを調整した後の振動速度スペクトル（モデル計算結果）を示している。 FIG. 7 shows the above vibration model because the 600 Hz spectral component is larger than the actual measurement result (excitation measurement result) of the vibration velocity spectrum when the laminate core is actually excited as shown in FIG. Is used to show the vibration velocity spectrum (model calculation result) after adjusting the weight sequence Wk so that the spectral component at 600 Hz decreases.
そして、図８は、上記の実際に積層体鉄心を励磁した時の振動速度スペクトルの実測結果（励磁測定結果）に対応して前述の図４のように設定した重み列Ｗｋ（元の電磁鋼板単板磁歪）に対して、積層体鉄心励磁時の振動速度スペクトルの内、６００Ｈｚのスペクトル成分が低下するように調整した重み列Ｗｋ（調整した重み）を示している。 FIG. 8 shows the weight row Wk (original electrical steel sheet) set as shown in FIG. 4 in correspondence with the actual measurement result (excitation measurement result) of the vibration velocity spectrum when the laminate core is actually excited. A weight row Wk (adjusted weight) adjusted so that a spectral component of 600 Hz in the vibration velocity spectrum at the time of exciting the laminated core is reduced with respect to (single plate magnetostriction) is shown.
これによって、６００Ｈｚのスペクトル成分が小さい振動速度スペクトルを備えた積層体鉄心を製造するためには、磁歪振動周波数スペクトル（重みデータ列Ｗｋ）の１００Ｈｚ成分と３００Ｈｚ成分の値が小さくなるような電磁鋼板であれば良いことがわかる。 Thus, in order to manufacture a laminated iron core having a vibration velocity spectrum with a small 600 Hz spectral component, a magnetic steel sheet in which the values of the 100 Hz component and the 300 Hz component of the magnetostrictive vibration frequency spectrum (weight data string Wk) are reduced. If it is, it turns out that it is good.
そして、上記のような磁歪振動周波数スペクトル（重みデータ列Ｗｋ）を有するように、新たな電磁鋼板の組成（成分）を決定した。 Then, a new composition (component) of the electrical steel sheet was determined so as to have the magnetostriction vibration frequency spectrum (weight data string Wk) as described above.
この結果、得られた新たな電磁鋼板を積層した積層体鉄心においては、振動特性は６００Ｈｚのスペクトル成分が低く、騒音特性も６００Ｈｚの値が小さくなった。 As a result, in the laminated iron core obtained by laminating the obtained new magnetic steel sheet, the vibration characteristic had a low spectral component of 600 Hz, and the noise characteristic also had a low value of 600 Hz.
このようにして、この実施形態においては、積層して積層体鉄心を製造するための電磁鋼板として、試行錯誤的な実験を繰り返すことなく、積層体鉄心となった状態での振動・騒音が小さくなるような周波数特性（磁歪振動周波数スペクトル特性）を備えた電磁鋼板を得ることができる。 Thus, in this embodiment, as an electromagnetic steel sheet for stacking and manufacturing a laminated core, vibration and noise in the state of the laminated core are reduced without repeating trial and error experiments. An electromagnetic steel sheet having such frequency characteristics (magnetostrictive vibration frequency spectrum characteristics) can be obtained.
また、需要家からの騒音周波数スペクトル特性の要望に応じて、電磁鋼板単板の磁歪振動周波数スペクトルがどのような特性であるべきかを検討し、それを設計することが可能となる。 Moreover, according to the request of the noise frequency spectrum characteristic from a consumer, it becomes possible to examine what kind of characteristic the magnetostrictive vibration frequency spectrum of the electromagnetic steel sheet single plate should be and to design it.
また、電磁鋼板を出荷する際に、当該電磁鋼板を積層して積層体鉄心とした時の振動スペクトル予測値（予測騒音値、励磁振動周波数スペクトル特性）をデータとして添付することが可能となり、商品付加価値を高めることができる。 In addition, when shipping electromagnetic steel sheets, it is possible to attach vibration spectrum predicted values (predicted noise values, excitation vibration frequency spectrum characteristics) when the electromagnetic steel sheets are laminated to form a laminated core as data. Added value can be increased.
なお、この実施形態では、交流の周波数が５０Ｈｚである地域で使用することを前提にして、励磁周波数ｆを５０Ｈｚとしているが、交流の周波数が６０Ｈｚである地域で使用する場合には、励磁周波数ｆを６０Ｈｚとすればよい。 In this embodiment, the excitation frequency f is set to 50 Hz on the assumption that the AC frequency is 50 Hz. However, when the AC frequency is 60 Hz, the excitation frequency f is 50 Hz. f may be set to 60 Hz.
本発明の実施例１を述べる。 A first embodiment of the present invention will be described.
この実施例１において用いた積層体鉄心を図９に示す。板厚０．２ｍｍの電磁鋼板を７０枚積層して、図９に示す寸法の積層体鉄心を作成し、小型の三相変圧器のモデル機（モデルトランス）を製作した。その際に、電磁鋼板を積層後、０．５〜１．２ｋｇ／ｃｍ２程度の面圧となるように積層体を締結した。積層体鉄心の重量は５０ｋｇ程度である。加振機の加振力は、検討の結果１５〜３０Ｎ程度であれば十分であることがわかった。 The laminated iron core used in Example 1 is shown in FIG. 70 electromagnetic steel sheets having a thickness of 0.2 mm were laminated to produce a laminated core having the dimensions shown in FIG. 9, and a small three-phase transformer model machine (model transformer) was produced. In that case, after laminating | stacking an electromagnetic steel plate, the laminated body was fastened so that it might become a surface pressure of about 0.5-1.2 kg / cm < 2 >. The weight of the laminated core is about 50 kg. As a result of the examination, it was found that the excitation force of the shaker is sufficient if it is about 15 to 30 N.
この小型のモデルトランスを加振して、上述した本発明の一実施形態における振動モデルを用いて振動スペクトル予測値を計算したところ、６００Ｈｚ成分が突出していた。そこで、重みデータ列Ｗｋを再検討し、積層体鉄心の振動スペクトル予測値における６００Ｈｚ成分が小さくなるようにした。そして、この重みデータ列Ｗｋと同様の周波数傾向の磁歪振動周波数スペクトル特性となるように、電磁鋼板の成分を調整した。 When this small model transformer was vibrated and the vibration spectrum prediction value was calculated using the vibration model in the embodiment of the present invention described above, a 600 Hz component was prominent. Therefore, the weight data string Wk was reexamined so that the 600 Hz component in the predicted vibration spectrum of the laminated core was reduced. And the component of the electromagnetic steel sheet was adjusted so that it might become the magnetostriction vibration frequency spectrum characteristic of the frequency tendency similar to this weight data row Wk.
この結果、積層体鉄心となった状態での振動・騒音が小さい電磁鋼板を製造することができた。 As a result, it was possible to manufacture an electrical steel sheet with low vibration and noise in the state of the laminated iron core.
１１ 積層体鉄心（モデル）
１２ ベークライト
１３ ばね
２１ 信号発生器
２２ 加振機
２３ ロードセル
２４ 振動センサ
２５ 周波数解析装置
11 Laminated iron core (model)
12 Bakelite 13 Spring 21 Signal Generator 22 Exciter 23 Load Cell 24 Vibration Sensor 25 Frequency Analyzer
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| CN108538559B (en) * | 2018-01-19 | 2020-06-23 | 江苏光辉电力器材有限公司 | Transformer core stacking device convenient for follow-up procedures |
| CN108538558B (en) * | 2018-01-19 | 2020-06-16 | 国网新疆电力有限公司乌鲁木齐供电公司 | Vibrating finishing device of transformer iron chip |
| JP7147831B2 (en) * | 2020-02-21 | 2022-10-05 | Ｊｆｅスチール株式会社 | Elastic matrix determination method and vibration analysis method for laminated core of transformer |
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| JP3408885B2 (en) * | 1995-04-10 | 2003-05-19 | 新日本製鐵株式会社 | Low-noise grain-oriented electrical steel sheets and laminated cores |
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