WO2021192353A1 - Bus duct - Google Patents
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- WO2021192353A1 WO2021192353A1 PCT/JP2020/033135 JP2020033135W WO2021192353A1 WO 2021192353 A1 WO2021192353 A1 WO 2021192353A1 JP 2020033135 W JP2020033135 W JP 2020033135W WO 2021192353 A1 WO2021192353 A1 WO 2021192353A1
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- WIPO (PCT)
- Prior art keywords
- housing
- magnetic material
- bus duct
- magnetic
- conductor
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02B—BOARDS, SUBSTATIONS OR SWITCHING ARRANGEMENTS FOR THE SUPPLY OR DISTRIBUTION OF ELECTRIC POWER
- H02B1/00—Frameworks, boards, panels, desks, casings; Details of substations or switching arrangements
- H02B1/20—Bus-bar or other wiring layouts, e.g. in cubicles, in switchyards
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G5/00—Installations of bus-bars
- H02G5/06—Totally-enclosed installations, e.g. in metal casings
Definitions
- the present invention relates to a bus duct.
- the switchgear electrically connects the circuit breaker, the power system, and the load.
- a bus bar with high heat dissipation performance is used for this connection, but a metal housing is placed around the bus bar to prevent electromagnetic waves from flowing into surrounding electronic devices due to the current of the bus bar and to prevent electric shock. Be placed.
- a low-cost steel material is usually used for the metal housing, but since the steel material is a magnetic material, the current flowing through the bus bar causes iron loss in the surrounding housing, causing the temperature of the housing to rise. To rise. When the temperature of the housing rises, there is a risk that a person who touches the housing may get burned, the temperature of the conductor may rise, and the characteristics such as an increase in the resistance of the conductor may deteriorate. As a technique for improving these, for example, Patent Document 1 is available.
- Patent Document 1 a box-shaped steel plate is formed around a conductor, and a part of the box-shaped steel plate is made of a non-magnetic synthetic resin plate to suppress iron loss and suppress a temperature rise of the housing. There is.
- Patent Document 1 since the housing is made of a synthetic resin plate having a low Young's modulus, a large electromagnetic repulsive force is generated between the short-circuit current and the eddy current flowing through the housing when a short-circuit current is passed through the bus duct. When it occurred, there was a possibility that the housing could not be held mechanically.
- synthetic resins have a lower thermal conductivity than metals, and there is a possibility that the temperature will rise due to the deterioration of heat dissipation.
- An object of the present invention is to provide a bus duct capable of improving heat dissipation performance and maintaining the mechanical strength of the housing without increasing the iron loss of the housing.
- a preferred example of the present invention is a housing and a conductor arranged in the housing, the housing including a non-magnetic material and a magnetic material, and between the non-magnetic material and the magnetic material.
- a bus duct having a corrosion prevention portion between dissimilar metals.
- FIG. It is a figure which shows the bus duct in Example 1.
- FIG. It is a figure which shows the housing of the bus duct in Example 1.
- FIG. It is a figure which shows the flow of the magnetic flux around a magnetic metal housing and a conductor. It is a figure which shows the flow of the magnetic flux around the housing and the conductor which combined the non-magnetic metal and the magnetic metal.
- FIG. It is a figure which shows the relationship between the bus duct and the direction of gravity in Example 1.
- FIG. It is a figure which shows the bus duct structure which has the housing which has the protrusion in Example 2.
- FIG. It is a figure which shows the bus duct structure which has the black-painted non-magnetic material in Example 2.
- FIG. It is a figure which shows the positional relationship between a plurality of conductors and a housing in Example 3.
- FIG. It is a figure which shows the positional relationship between a plurality of conductors arranged in a triangular shape and a housing in the modification of Example 3.
- FIG. It is a figure which shows the positional relationship between a plurality of conductors arranged diagonally, and a housing in the modification of Example 3.
- FIG. It is a figure which shows the bus duct in Example 4.
- Example 1 shown in FIG. 1 shows a bus duct 1 composed of a housing 2 and a conductor 100 arranged in the housing 2.
- a bus duct is an electric power trunk system that can meet the electric power demand of a building or a factory, for example.
- FIG. 2 is a diagram showing a housing 2.
- the housing 2 has a surface of a magnetic body 102, a surface of a non-magnetic body 103, and a corrosion prevention section 104 between dissimilar metals.
- a conductor current of 199 flows through the conductor 100.
- the magnetic material 102 is a steel material which is a low-cost housing material
- the non-magnetic material 103 is made of non-magnetic stainless steel
- the galvanic corrosion prevention portion 104 is made of an insulator or the like. It will be described that the loss of the housing can be suppressed according to the first embodiment as compared with FIG.
- FIG. 3 shows a bus duct of a housing composed of only a conductor 100 and a metal magnetic material 102, and is a diagram showing a comparative example for comparison with the present embodiment.
- the magnetic flux 200 passing only inside the housing made of steel is larger.
- the iron loss of the housing increases and the temperature rise increases.
- equation (1) when the current becomes high frequency, the eddy current loss calculated by the square of the frequency increases, and the iron loss W becomes larger.
- FIG. 4 is a diagram showing a configuration example in which the magnetic flux 200 passing only in the housing is reduced in order to reduce iron loss, and a comparative example for comparison with the present embodiment.
- the housing is composed of a magnetic material 102 and a non-magnetic material 103. Since the magnetic resistance of the non-magnetic material 103 is much higher than that of the magnetic material 102, the magnetic flux flowing into the housing is smaller than that of the case where the non-magnetic material 103 is composed only of the magnetic material 102, and iron loss can be reduced.
- the electromagnetic repulsive force becomes larger.
- the housing is distorted. Therefore, by using a material having a high Young's modulus that can maintain the mechanical strength even when a large electromagnetic repulsive force is generated in the housing as the non-magnetic material 103, the housing having a high mechanical strength can be obtained. ..
- an insulating material is provided between the magnetic material 102 and the non-magnetic material 103, but a material in the middle of the ionization tendency of the magnetic material 102 and the non-magnetic material 103 is used as a material for preventing corrosion between dissimilar metals. It may be used for 104. Even in that case, corrosion between dissimilar metals can be prevented.
- the galvanic corrosion prevention portion 104 is made of a material such as nickel.
- the corrosion prevention portion 104 is made of a material such as nickel.
- a fixing tool 301 such as a screw is used to fix the magnetic body 102, the non-magnetic body 103, and the galvanic corrosion prevention portion 104 between dissimilar metals.
- the fixture 301 is a magnetic material
- the magnetic metal and the non-magnetic metal can come into contact with each other via the fixture 301. Therefore, the magnetic fixture 301 is plated to prevent corrosion between dissimilar metals. .. With such a configuration, contact between the magnetic metal and the non-magnetic metal can be avoided, and corrosion between dissimilar metals can be prevented.
- the housing is described as a part of the non-magnetic material, the relationship between the width (magnetic path length) 501 of the non-magnetic material 103 and the magnetic resistance will be described with reference to FIG.
- the magnetic resistance of the housing is calculated by the magnetic permeability of the conductor material, the magnetic path cross-sectional area, and the magnetic path length as shown in the equation (2).
- the magnetic resistance of the housing shown in this embodiment includes the total magnetic path length 506 of the magnetic material determined by the lengths (magnetic path lengths) 503, 504, and 505 of the magnetic body 102, the width 501 of the non-magnetic body 103, and dissimilar metals. It is calculated by the equation (3) using the width (magnetic path length) 502 of the intercorrosion prevention unit 104.
- the magnetic permeability ⁇ 2 of a non-magnetic metal is almost the same as that of the corroded portion between dissimilar metals ⁇ 3, and is about 1/5000 of the magnetic permeability ⁇ 1 of a magnetic metal. Therefore, the equation (3) can be expressed as the equation (4), and it can be seen that the reluctance is higher than the reluctance when the housing is entirely made of magnetic metal.
- the magnetic flux path does not have to pass through the central portion of the housing as shown in FIG.
- the configuration in which the magnetic material length 506 is longer than the non-magnetic material width 501 has been described, when the non-magnetic material width 501 is longer than the magnetic material length 506, iron loss can be further reduced.
- the width 501 of the non-magnetic material and the width 502 of the corrosion prevention portion 104 between dissimilar metals is 1/5000 of the total magnetic path length 506 of the magnetic material
- the reluctance can be expressed by the formula (5).
- the reluctance is twice the magnetic resistance when the housing is made entirely of magnetic material, the magnetic flux is reduced by half, and the eddy current loss can be reduced by 1/4 from equation (1). can.
- FIG. 7 shows the relationship between the bus duct of Example 1 and the direction of gravity 601.
- the bus duct 1 is arranged in the upper part of the bus duct chamber, and electronic parts and the like are arranged in the lower part of the bus duct chamber.
- a magnetic body 102 that absorbs magnetic flux is arranged on the side close to the electronic component, that is, in the direction of gravity 601.
- the upper part of the bus duct 1 is often a ceiling, it is desirable to form a non-magnetic material through which magnetic flux passes in the direction opposite to the direction of gravity.
- the heat conductivity is generally lower than that of magnetic materials in the direction opposite to gravity, which has the highest heat dissipation effect due to convection.
- a configuration in which a magnetic material is arranged is desirable.
- the first embodiment it is possible to improve the heat dissipation performance and maintain the mechanical strength of the housing without increasing the iron loss of the housing.
- the bus duct 1 of the second embodiment shown in FIG. 8 includes a housing composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and a bus duct composed of a conductor 100 arranged in the housing.
- the non-magnetic material 103 is provided with protrusions 401 for increasing the surface area.
- the thermal conductivity of a non-magnetic metal for example, stainless steel is lower than the thermal conductivity of a magnetic metal, for example, steel, so the heat dissipation performance of the housing is low.
- the heat dissipation performance by convection and radiation is improved, and the surface area is increased by providing the protrusion 401 on the non-magnetic material 103.
- the surface area on the outside of the non-magnetic material 103 may be increased to improve heat dissipation performance.
- the same effect can be obtained by arranging the protrusion 401 inside the housing surface (conductor side), but if the protrusion shape is metal, the distance between the conductors becomes short and dielectric breakdown may occur. Therefore, it is desirable to provide a protrusion on the outside of the housing. Further, the heat dissipation performance may be improved by providing a recess inside the non-magnetic body 103 on the housing surface.
- the non-magnetic material 103 is provided with the protrusions 401, but the same effect can be obtained by providing the magnetic material 102 with the protrusions or recesses.
- a configuration provided with protrusions 401 has been described in order to improve heat dissipation performance due to convection and radiation.
- a non-magnetic material having a black coating 105 on the housing 2 of the bus duct may be used. According to such a configuration, the heat dissipation performance due to convection cannot be improved, but the heat dissipation performance due to radiation can be improved.
- the second embodiment as shown in the first embodiment, it is possible to maintain the mechanical strength of the housing without increasing the iron loss of the housing, and further improve the heat dissipation performance of the bus duct. be able to.
- FIG. 10 is a diagram showing the configuration of the bus duct of the third embodiment.
- the bus duct is composed of a housing 2 composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and conductors 100A, 100B, and 100C arranged in the housing 2.
- the conductor 100A is the closest to the housing 2 when the distances between the other conductors 100B, 100C and the housing 2 are compared. Is placed in a short position.
- the surface of the housing 2 closest to the conductor 100A is made of a non-magnetic material 103.
- the influence of the magnetic flux 201 via the air in the magnetic flux described in the first embodiment can be reduced and the iron loss can be suppressed.
- the arrangement relationship between the conductors 100A, 100B, 100C and the housing 2 is determined by the insulation distance, and the non-magnetic material is arranged in the housing in which the distances between the conductors 100A, 100B, 100C and the housing 2 are relatively close. It should be done. Further, as described with reference to FIG. 10, the same effect can be obtained by the conductor arrangement as shown in FIGS. 11 and 12.
- FIG. 11 is a diagram showing the positional relationship between the conductors 100A, 100B, 100C and the housing 2 arranged in a triangular shape.
- FIG. 12 is a diagram showing the positional relationship between the conductors 100A, 100B, 100C and the housing 2 arranged diagonally.
- the conductor 100A is arranged at a position closest to the housing 2 as compared with the other conductors 100B and 100C.
- the non-magnetic material 103 is arranged in the housing 2 at the position closest to the conductor 100A.
- the heat dissipation performance can be improved, the mechanical strength of the housing can be maintained, and the influence of the magnetic flux 201 via air in the magnetic flux can be reduced. Furthermore, iron loss can be suppressed.
- FIG. 13 is a diagram showing a bus duct of the fourth embodiment.
- the bus duct is composed of a housing 2 composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and conductors 101A, 101B, and 101C arranged in the housing 2.
- the conductors 101A, 101B, and 101C are provided with recesses 402, respectively.
- the region having a high current density can be made into the facing surface of each of the three-phase conductors 101A, 101B, 101C, and the conductors can be separated from each other. The same effect as when the distance is shortened can be obtained.
- Bus duct 2 Housing 100, 100A, 100B, 100C ... Conductors 101A, 101B, 101C ... Conductors with recesses 102 ... Magnetic material 103 ... Non-magnetic material 104 ... Galvanic corrosion prevention part 199 ... Conductor current 301 ... Fixed Tool 401 ... Protrusion
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Installation Of Bus-Bars (AREA)
- Patch Boards (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
Abstract
This bus duct has a housing and a conductor disposed inside the housing, wherein the housing includes a non-magnetic body and a magnetic body, and has an intra-different-metal corrosion prevention section between the non-magnetic body and the magnetic body.
Description
本発明は、バスダクトに関するものである。
The present invention relates to a bus duct.
スイッチギヤは遮断器と電力系統、負荷とを電気的に接続している。この接続に放熱性能が高いバスバーが用いられるが、バスバーの電流により周囲の電子機器などに電磁波が流入するのを防止することや、感電防止のためにバスバーの周囲には金属製の筐体が配置される。
The switchgear electrically connects the circuit breaker, the power system, and the load. A bus bar with high heat dissipation performance is used for this connection, but a metal housing is placed around the bus bar to prevent electromagnetic waves from flowing into surrounding electronic devices due to the current of the bus bar and to prevent electric shock. Be placed.
金属製の筐体は、通常コストの低い鋼材が採用されるが、鋼材は磁性体であるため、バスバーに流れる電流により周囲に配置される筐体に鉄損が発生し、筐体の温度が上昇する。筐体の温度が上昇すると、筐体に触れた人がやけどをするリスクや、導体温度の上昇を招き、導体の抵抗の増加など特性が悪化する可能性がある。これらを改善するため技術として、例えば特許文献1がある。
A low-cost steel material is usually used for the metal housing, but since the steel material is a magnetic material, the current flowing through the bus bar causes iron loss in the surrounding housing, causing the temperature of the housing to rise. To rise. When the temperature of the housing rises, there is a risk that a person who touches the housing may get burned, the temperature of the conductor may rise, and the characteristics such as an increase in the resistance of the conductor may deteriorate. As a technique for improving these, for example, Patent Document 1 is available.
特許文献1では、導体の周囲に鋼板の箱状体を形成し、その一部を非磁性体である合成樹脂板とすることで、鉄損を抑制し、筐体の温度上昇を抑制している。
In Patent Document 1, a box-shaped steel plate is formed around a conductor, and a part of the box-shaped steel plate is made of a non-magnetic synthetic resin plate to suppress iron loss and suppress a temperature rise of the housing. There is.
特許文献1では、筐体をヤング率の低い合成樹脂板で形成しているため、バスダクトに短絡電流を流した際に、短絡電流と筐体に流れる渦電流との間で大きな電磁反発力が発生した際、筐体が機械的に保持できない可能性があった。
In Patent Document 1, since the housing is made of a synthetic resin plate having a low Young's modulus, a large electromagnetic repulsive force is generated between the short-circuit current and the eddy current flowing through the housing when a short-circuit current is passed through the bus duct. When it occurred, there was a possibility that the housing could not be held mechanically.
さらに、一般的に合成樹脂は金属と比較して熱伝導率が低く、放熱性が悪化するために温度が上昇する可能性があった。
Furthermore, in general, synthetic resins have a lower thermal conductivity than metals, and there is a possibility that the temperature will rise due to the deterioration of heat dissipation.
本発明の目的は、筐体の鉄損を増大させることなく放熱性能を向上し、筐体の機械強度を保持できるバスダクトを提供することにある。
An object of the present invention is to provide a bus duct capable of improving heat dissipation performance and maintaining the mechanical strength of the housing without increasing the iron loss of the housing.
本発明の好ましい一例としては、筐体と、前記筐体内に配置された導体とを有し、前記筐体は、非磁性体と磁性体を含み、前記非磁性体と前記磁性体の間には異種金属間腐食防止部を有するバスダクトである。
A preferred example of the present invention is a housing and a conductor arranged in the housing, the housing including a non-magnetic material and a magnetic material, and between the non-magnetic material and the magnetic material. Is a bus duct having a corrosion prevention portion between dissimilar metals.
本発明によれば、筐体の鉄損を増大させることなく放熱性能を向上し、筐体の機械強度を保持することが可能になる。
According to the present invention, it is possible to improve heat dissipation performance and maintain the mechanical strength of the housing without increasing the iron loss of the housing.
以下に、本発明の実施例について図面を用いて説明する。
Hereinafter, examples of the present invention will be described with reference to the drawings.
図1に示す実施例1は、筐体2と、筐体2内に配置された導体100で構成されるバスダクト1を示している。バスダクトは、例えばビルや工場などの電力需要に対応できる電力幹線システムである。図2は筐体2を示す図である。筐体2は磁性体102の面と非磁性体103の面、異種金属間腐食防止部104を有する。導体100には導体電流199が流れる。
Example 1 shown in FIG. 1 shows a bus duct 1 composed of a housing 2 and a conductor 100 arranged in the housing 2. A bus duct is an electric power trunk system that can meet the electric power demand of a building or a factory, for example. FIG. 2 is a diagram showing a housing 2. The housing 2 has a surface of a magnetic body 102, a surface of a non-magnetic body 103, and a corrosion prevention section 104 between dissimilar metals. A conductor current of 199 flows through the conductor 100.
導体電流は交流であるため、電流方向は図に示すように紙面に対して垂直となる双方向に流れる。例えば、磁性体102は低コストの筐体材料である鋼材で、非磁性体103は非磁性ステンレス鋼、異種金属間腐食防止部104は絶縁体などで構成される。図3と比較して実施例1によれば筐体の損失を抑制できることを説明する。
Since the conductor current is alternating current, the current direction flows in both directions perpendicular to the paper surface as shown in the figure. For example, the magnetic material 102 is a steel material which is a low-cost housing material, the non-magnetic material 103 is made of non-magnetic stainless steel, and the galvanic corrosion prevention portion 104 is made of an insulator or the like. It will be described that the loss of the housing can be suppressed according to the first embodiment as compared with FIG.
図3は、導体100と金属の磁性体102でのみ構成される筐体のバスダクトを示しており、本実施例と比較するための比較例を示す図である。各導体に同位相の電流199を流した際、導体付近に磁束が発生する。この磁束は、導体周囲に空気を介した磁束201や筐体内のみを通る磁束200に分かれる。
FIG. 3 shows a bus duct of a housing composed of only a conductor 100 and a metal magnetic material 102, and is a diagram showing a comparative example for comparison with the present embodiment. When a current 199 of the same phase is passed through each conductor, a magnetic flux is generated near the conductor. This magnetic flux is divided into a magnetic flux 201 that passes through air around the conductor and a magnetic flux 200 that passes only inside the housing.
磁気抵抗の大きい空気を介する磁束201と比較して、鋼材で構成された筐体内のみを通る磁束200は大きい。これらの磁束が大きくなると筐体の鉄損が増加し、温度上昇が高くなる。式(1)に示すように、電流が高周波になると周波数の二乗で計算される渦電流損が増大し、鉄損Wがより大きくなる。
Compared with the magnetic flux 201 via air having a large magnetic resistance, the magnetic flux 200 passing only inside the housing made of steel is larger. When these magnetic fluxes increase, the iron loss of the housing increases and the temperature rise increases. As shown in equation (1), when the current becomes high frequency, the eddy current loss calculated by the square of the frequency increases, and the iron loss W becomes larger.
図4は、鉄損を低減するために、筐体内のみを通る磁束200を低減した構成例を示し、本実施例と比較するための比較例を示す図である。筐体は磁性体102と非磁性体103で構成される。非磁性体103の磁気抵抗は磁性体102よりも非常に高いため、磁性体102でのみ構成される場合と比較して筐体に流入する磁束が小さくなり、鉄損を低減することができる。
FIG. 4 is a diagram showing a configuration example in which the magnetic flux 200 passing only in the housing is reduced in order to reduce iron loss, and a comparative example for comparison with the present embodiment. The housing is composed of a magnetic material 102 and a non-magnetic material 103. Since the magnetic resistance of the non-magnetic material 103 is much higher than that of the magnetic material 102, the magnetic flux flowing into the housing is smaller than that of the case where the non-magnetic material 103 is composed only of the magnetic material 102, and iron loss can be reduced.
しかしながら、磁性体102と非磁性体103が異なる金属である場合、接触面に水蒸気など水分が含まれると異種金属間腐食が発生し、筐体の機械強度の劣化が発生する。そこで、図1に示すように、磁性体102と非磁性体103の間に絶縁材からなる異種金属間腐食防止部104を構成することで、異種金属間腐食を防止することができる。
However, when the magnetic material 102 and the non-magnetic material 103 are different metals, corrosion between dissimilar metals occurs when the contact surface contains moisture such as water vapor, and the mechanical strength of the housing deteriorates. Therefore, as shown in FIG. 1, by forming a galvanic corrosion prevention portion 104 made of an insulating material between the magnetic material 102 and the non-magnetic material 103, corrosion between dissimilar metals can be prevented.
次に、筐体の電磁反発力について説明する。導体に電流が流れた際、筐体に磁束が流入するが、その磁束を打ち消すように筐体には渦電流が発生する。その渦電流と導体電流により、筐体と導体には電磁反発力が発生する。
Next, the electromagnetic repulsive force of the housing will be described. When a current flows through the conductor, a magnetic flux flows into the housing, but an eddy current is generated in the housing so as to cancel the magnetic flux. Due to the eddy current and the conductor current, an electromagnetic repulsive force is generated in the housing and the conductor.
例えば、導体電流が短絡電流のような非常に大きな電流が流れる場合、電磁反発力はより大きくなる。筐体に大きな電磁反発力が発生すると筐体に歪みが生じる。そこで、筐体に大きな電磁反発力が生じても機械的強度を保持することができるヤング率の高い材料を非磁性体103として用いることで、高い機械的強度を持つ筐体とすることができる。
For example, when a very large current such as a short-circuit current flows through the conductor current, the electromagnetic repulsive force becomes larger. When a large electromagnetic repulsive force is generated in the housing, the housing is distorted. Therefore, by using a material having a high Young's modulus that can maintain the mechanical strength even when a large electromagnetic repulsive force is generated in the housing as the non-magnetic material 103, the housing having a high mechanical strength can be obtained. ..
本実施例1では、磁性体102と非磁性体103の間に絶縁材を設けることを記載したが、磁性体102と非磁性体103のイオン化傾向の中間にある材料を異種金属間腐食防止部104に用いてもよい。その場合でも、異種金属間の腐食を防止することができる。
In the first embodiment, it is described that an insulating material is provided between the magnetic material 102 and the non-magnetic material 103, but a material in the middle of the ionization tendency of the magnetic material 102 and the non-magnetic material 103 is used as a material for preventing corrosion between dissimilar metals. It may be used for 104. Even in that case, corrosion between dissimilar metals can be prevented.
例えば、磁性体102が鉄材である金属で構成され、非磁性体103がステンレス鋼であるSUS304などの金属で構成される場合に、異種金属間腐食防止部104をニッケルなどの材料とする。異種金属間腐食防止部104を金属とすることで、筐体をすべて導電性とすることでノイズの放射量を低減することができる。ただし、導体電流が商用周波数のような低い周波数であれば、他の機器に与える影響は小さいため、非磁性体は金属と同程度のヤング率を持つ材料であれば金属でなくてもよい。
For example, when the magnetic material 102 is made of a metal such as iron and the non-magnetic material 103 is made of a metal such as SUS304 which is stainless steel, the galvanic corrosion prevention portion 104 is made of a material such as nickel. By making the corrosion prevention portion 104 between dissimilar metals made of metal, it is possible to reduce the amount of noise radiation by making all the housings conductive. However, if the conductor current is a low frequency such as a commercial frequency, the influence on other devices is small, so that the non-magnetic material does not have to be a metal as long as it is a material having a Young's modulus similar to that of a metal.
尚、図5に示すように、本実施例では、磁性体102と非磁性体103と異種金属間腐食防止部104との間を固定するため、ねじなどの固定具301が利用される。固定具301が磁性体の場合、固定具301を介して、磁性体金属と非磁性体金属の接触ができるため、磁性体の固定具301に異種金属間腐食防止用のメッキ等が施してある。そのような構成にすることで磁性体金属と非磁性体金属の接触を避け、異種金属間腐食を防ぐことができる。
As shown in FIG. 5, in this embodiment, a fixing tool 301 such as a screw is used to fix the magnetic body 102, the non-magnetic body 103, and the galvanic corrosion prevention portion 104 between dissimilar metals. When the fixture 301 is a magnetic material, the magnetic metal and the non-magnetic metal can come into contact with each other via the fixture 301. Therefore, the magnetic fixture 301 is plated to prevent corrosion between dissimilar metals. .. With such a configuration, contact between the magnetic metal and the non-magnetic metal can be avoided, and corrosion between dissimilar metals can be prevented.
さらに、本実施例では3本の導体100を用いて説明したが、導体の導体電流199の位相は同相であっても、三相であっても同様の効果が得られ、相数には依存しない。また、三本の導体で説明をしたが、少なくとも一本の導体があれば同様の効果が得られる。
Further, although the description has been made using three conductors 100 in this embodiment, the same effect can be obtained regardless of whether the conductor current 199 is in-phase or three-phase, and depends on the number of phases. do not. Moreover, although the explanation was given with three conductors, the same effect can be obtained if there is at least one conductor.
ここで、筐体は一部の非磁性体と記載したが、図6を用いて、非磁性体103の幅(磁路長)501と磁気抵抗の関係について説明する。筐体の磁気抵抗は式(2)に示すように導体材料の透磁率、磁路断面積、磁路長で計算される。
Here, although the housing is described as a part of the non-magnetic material, the relationship between the width (magnetic path length) 501 of the non-magnetic material 103 and the magnetic resistance will be described with reference to FIG. The magnetic resistance of the housing is calculated by the magnetic permeability of the conductor material, the magnetic path cross-sectional area, and the magnetic path length as shown in the equation (2).
本実施例に示す筐体の磁気抵抗は、磁性体102の長さ(磁路長)503、504、505で決まる磁性体の磁路長合計506と、非磁性体103の幅501と異種金属間腐食防止部104の幅(磁路長)502を用いて式(3)で計算される。
The magnetic resistance of the housing shown in this embodiment includes the total magnetic path length 506 of the magnetic material determined by the lengths (magnetic path lengths) 503, 504, and 505 of the magnetic body 102, the width 501 of the non-magnetic body 103, and dissimilar metals. It is calculated by the equation (3) using the width (magnetic path length) 502 of the intercorrosion prevention unit 104.
一般に、非磁性体金属の透磁率μ2は異種金属間腐食部μ3とほぼ同等であり、磁性体金属の透磁率μ1の1/5000程度の大きさである。そのため、式(3)は式(4)のように表すことができ、筐体がすべて磁性体金属で構成される場合の磁気抵抗よりも高い磁気抵抗を持つことが分かる。
In general, the magnetic permeability μ 2 of a non-magnetic metal is almost the same as that of the corroded portion between dissimilar metals μ 3, and is about 1/5000 of the magnetic permeability μ 1 of a magnetic metal. Therefore, the equation (3) can be expressed as the equation (4), and it can be seen that the reluctance is higher than the reluctance when the housing is entirely made of magnetic metal.
なお、図6に示す磁束の経路を用いて非磁性体幅501と磁気抵抗の関係を示したが、磁束の経路は図6に示すように筐体の中央部を通らなくてもよい。さらに、磁性体長さ506が非磁性体幅501よりも長い構成で説明したが、非磁性体幅501が磁性体長さ506より長い場合には、より鉄損を低減することができる。
Although the relationship between the non-magnetic material width 501 and the magnetoresistance is shown using the magnetic flux path shown in FIG. 6, the magnetic flux path does not have to pass through the central portion of the housing as shown in FIG. Further, although the configuration in which the magnetic material length 506 is longer than the non-magnetic material width 501 has been described, when the non-magnetic material width 501 is longer than the magnetic material length 506, iron loss can be further reduced.
ただし、一般的に磁性体である鋼材などに対し、非磁性体であるステンレス鋼などは値段が高く、筐体コストを向上する可能性があるため、鉄損の大きさに応じ、非磁性体幅を決定するのがよい。例えば、非磁性体幅501と異種金属間腐食防止部104の幅502の合計値が磁性体の磁路長合計506の1/5000の場合、磁気抵抗は式(5)のように表すことができる。この場合には筐体をすべて磁性体とした場合の磁気抵抗の2倍の磁気抵抗となり、磁束を1/2に低減し、式(1)から渦電流損は1/4に低減することができる。
However, compared to steel materials, which are generally magnetic materials, stainless steel, which is a non-magnetic material, is expensive and may increase the housing cost. Therefore, depending on the size of iron loss, non-magnetic materials It is better to determine the width. For example, when the total value of the width 501 of the non-magnetic material and the width 502 of the corrosion prevention portion 104 between dissimilar metals is 1/5000 of the total magnetic path length 506 of the magnetic material, the reluctance can be expressed by the formula (5). can. In this case, the reluctance is twice the magnetic resistance when the housing is made entirely of magnetic material, the magnetic flux is reduced by half, and the eddy current loss can be reduced by 1/4 from equation (1). can.
また、図7は実施例1のバスダクトと重力方向601の関係を示す。一般にバスダクト1はバスダクト室の上部に配置され、バスダクト室下部に電子部品などが配置される。その電子部品に対して、バスダクト1内の導体からの電磁波を抑制するために、電子部品に近い側、つまり重力方向601には磁束を吸収する磁性体102を配置する。一方、バスダクト1の上部は天井の場合が多いので重力方向と反対方向には磁束が通過する非磁性体を構成することが望ましい。さらに、筐体の温度の上昇によって発生する自然対流は重力と反対方向に流れるため、対流による放熱効果が最も高い重力と反対方向に、一般的には磁性体に比べて熱伝導性の低い非磁性体を配置する構成が望ましい。
Further, FIG. 7 shows the relationship between the bus duct of Example 1 and the direction of gravity 601. Generally, the bus duct 1 is arranged in the upper part of the bus duct chamber, and electronic parts and the like are arranged in the lower part of the bus duct chamber. In order to suppress electromagnetic waves from the conductor in the bus duct 1 with respect to the electronic component, a magnetic body 102 that absorbs magnetic flux is arranged on the side close to the electronic component, that is, in the direction of gravity 601. On the other hand, since the upper part of the bus duct 1 is often a ceiling, it is desirable to form a non-magnetic material through which magnetic flux passes in the direction opposite to the direction of gravity. Furthermore, since the natural convection generated by the rise in the temperature of the housing flows in the direction opposite to gravity, the heat conductivity is generally lower than that of magnetic materials in the direction opposite to gravity, which has the highest heat dissipation effect due to convection. A configuration in which a magnetic material is arranged is desirable.
実施例1によれば、筐体の鉄損を増大させることなく放熱性能を向上し、筐体の機械強度を保持することが可能になる。
According to the first embodiment, it is possible to improve the heat dissipation performance and maintain the mechanical strength of the housing without increasing the iron loss of the housing.
図8に示す実施例2のバスダクト1は、磁性体102と非磁性体103、異種金属間腐食防止部104で構成される筐体と、筐体内に配置された導体100で構成されるバスダクトを示しており、非磁性体103には表面積を増大させるための突起401が設けられる。
The bus duct 1 of the second embodiment shown in FIG. 8 includes a housing composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and a bus duct composed of a conductor 100 arranged in the housing. As shown, the non-magnetic material 103 is provided with protrusions 401 for increasing the surface area.
一般的に磁性体金属、例えば鋼材の熱伝導率に対し、非磁性金属、例えばステンレス鋼の熱伝導率は低いため、筐体の放熱性能が低い。この熱伝導の低さを補うために、対流と輻射による放熱性能を向上させ、非磁性体103に突起401を設けることで表面積を増大させた構造である。
Generally, the thermal conductivity of a non-magnetic metal, for example, stainless steel is lower than the thermal conductivity of a magnetic metal, for example, steel, so the heat dissipation performance of the housing is low. In order to compensate for this low heat conduction, the heat dissipation performance by convection and radiation is improved, and the surface area is increased by providing the protrusion 401 on the non-magnetic material 103.
突起401の代わりに非磁性体103の外側に凹部を設けることで、非磁性体103の外側の表面積を増大させて、放熱性能を向上させるようにしてもよい。
By providing a recess on the outside of the non-magnetic material 103 instead of the protrusion 401, the surface area on the outside of the non-magnetic material 103 may be increased to improve heat dissipation performance.
尚、突起401を筐体面の内側(導体側)に配置しても同様の効果が得られるが、突起形状が金属である場合、導体間との距離が近くなり、絶縁破壊が発生する可能性があるため、筐体外側に突起部を設けることが望ましい。また、筐体面の非磁性体103の内側に凹部を設けることで、放熱性能を向上させるようにしてもよい。
The same effect can be obtained by arranging the protrusion 401 inside the housing surface (conductor side), but if the protrusion shape is metal, the distance between the conductors becomes short and dielectric breakdown may occur. Therefore, it is desirable to provide a protrusion on the outside of the housing. Further, the heat dissipation performance may be improved by providing a recess inside the non-magnetic body 103 on the housing surface.
また、本実施例では非磁性体103に突起401を設ける構成としたが、磁性体102に突起もしくは凹部を設ける構成でも同様の効果が得られる。
Further, in this embodiment, the non-magnetic material 103 is provided with the protrusions 401, but the same effect can be obtained by providing the magnetic material 102 with the protrusions or recesses.
本実施例2では対流、輻射による放熱性能を向上させるために突起401を備えた構成で説明した。さらに、変形例として、図9に示すように、バスダクトの筐体2における黒色塗装105がされた非磁性体としてもよい。そのような構成によれば、対流による放熱性能は向上できないが、輻射による放熱性能を向上させることができる。
In the second embodiment, a configuration provided with protrusions 401 has been described in order to improve heat dissipation performance due to convection and radiation. Further, as a modification, as shown in FIG. 9, a non-magnetic material having a black coating 105 on the housing 2 of the bus duct may be used. According to such a configuration, the heat dissipation performance due to convection cannot be improved, but the heat dissipation performance due to radiation can be improved.
実施例2によれば、実施例1に示したように、筐体の鉄損を増大させることなく、筐体の機械強度を保持することが可能になるとともに、さらにバスダクトの放熱性能を向上させることができる。
According to the second embodiment, as shown in the first embodiment, it is possible to maintain the mechanical strength of the housing without increasing the iron loss of the housing, and further improve the heat dissipation performance of the bus duct. be able to.
図10は実施例3のバスダクトの構成を示す図である。バスダクトは、磁性体102と非磁性体103、異種金属間腐食防止部104で構成される筐体2と、筐体2内に配置された導体100A、100B、100Cで構成される。図10に示すように、筐体2と導体100A、100B、100Cの位置関係について、導体100Aは、他の導体100B、100Cと筐体2との距離を比べると、最も筐体2との距離が短い位置に配置されている。その導体100Aに最も近い筐体2の面は非磁性体103で構成されている。
FIG. 10 is a diagram showing the configuration of the bus duct of the third embodiment. The bus duct is composed of a housing 2 composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and conductors 100A, 100B, and 100C arranged in the housing 2. As shown in FIG. 10, regarding the positional relationship between the housing 2 and the conductors 100A, 100B, 100C, the conductor 100A is the closest to the housing 2 when the distances between the other conductors 100B, 100C and the housing 2 are compared. Is placed in a short position. The surface of the housing 2 closest to the conductor 100A is made of a non-magnetic material 103.
実施例3によれば、実施例1で述べた磁束の中で空気を介する磁束201の影響を低減し、鉄損を抑制することができる。尚、導体100A、100B、100Cと筐体2の配置関係は絶縁距離によって決定され、導体100A、100B、100Cと筐体2の距離が相対的に近い配置となる筐体に非磁性体が配置されればよい。さらに、図10を用いて説明をしたが、図11や図12のような導体配置でも同様の効果が得られる。
According to the third embodiment, the influence of the magnetic flux 201 via the air in the magnetic flux described in the first embodiment can be reduced and the iron loss can be suppressed. The arrangement relationship between the conductors 100A, 100B, 100C and the housing 2 is determined by the insulation distance, and the non-magnetic material is arranged in the housing in which the distances between the conductors 100A, 100B, 100C and the housing 2 are relatively close. It should be done. Further, as described with reference to FIG. 10, the same effect can be obtained by the conductor arrangement as shown in FIGS. 11 and 12.
図11は、三角形状に並べた配置の導体100A、100B、100Cと筐体2の位置関係を示す図である。図12は、斜めに並べた配置の導体100A、100B、100Cと筐体2の位置関係を示す図である。図11と図12のいずれの場合でも、導体100Aが他の導体100B、100Cに比べて最も筐体2に近い位置に配置されている。その導体100Aとの距離が最も近い位置にある筐体2に非磁性体103が配置されている。
FIG. 11 is a diagram showing the positional relationship between the conductors 100A, 100B, 100C and the housing 2 arranged in a triangular shape. FIG. 12 is a diagram showing the positional relationship between the conductors 100A, 100B, 100C and the housing 2 arranged diagonally. In both cases of FIGS. 11 and 12, the conductor 100A is arranged at a position closest to the housing 2 as compared with the other conductors 100B and 100C. The non-magnetic material 103 is arranged in the housing 2 at the position closest to the conductor 100A.
実施例3によれば、実施例1に示したように放熱性能を向上し、筐体の機械強度を保持することが可能になるとともに、磁束の中で空気を介する磁束201の影響を低減し、さらに、鉄損を抑制することができる。
According to the third embodiment, as shown in the first embodiment, the heat dissipation performance can be improved, the mechanical strength of the housing can be maintained, and the influence of the magnetic flux 201 via air in the magnetic flux can be reduced. Furthermore, iron loss can be suppressed.
図13は実施例4のバスダクトを示す図である。バスダクトは、磁性体102と非磁性体103、異種金属間腐食防止部104から構成される筐体2と、筐体2内に配置された導体101A、101B、101Cから構成される。導体101A、101B、101Cには、それぞれ凹部402が設けられている。
FIG. 13 is a diagram showing a bus duct of the fourth embodiment. The bus duct is composed of a housing 2 composed of a magnetic material 102, a non-magnetic material 103, and a corrosion prevention portion 104 between dissimilar metals, and conductors 101A, 101B, and 101C arranged in the housing 2. The conductors 101A, 101B, and 101C are provided with recesses 402, respectively.
導体に交流電流が通流した際、表皮効果により電流表面に電流が集中するが、導体に凹部があると、導体の電流密度分布を制御することが可能となる。例えば、図13に示すように三相の導体101A、101B、101Cそれぞれが対向する面と反対側に、凹部402を設けることで、凹部402と逆方向に電流集中が発生する。三相電流が作る磁束の合計は、導体間距離によって影響を受け、導体間距離が長いと相殺効果が小さく、導体間距離が短いと相殺効果が高まる。
When an alternating current flows through the conductor, the current concentrates on the current surface due to the skin effect, but if the conductor has a recess, it becomes possible to control the current density distribution of the conductor. For example, as shown in FIG. 13, by providing the recess 402 on the side opposite to the surface where the three- phase conductors 101A, 101B, and 101C face each other, current concentration is generated in the direction opposite to the recess 402. The total magnetic flux produced by the three-phase current is affected by the distance between conductors. When the distance between conductors is long, the canceling effect is small, and when the distance between conductors is short, the canceling effect is enhanced.
実施例4によれば、凹部402を有する導体101A、101B、101Cを配置することで、電流密度が高い領域を三相の導体101A、101B、101Cそれぞれの対向面にすることができ、導体間距離を短くした場合と同様の効果が得られる。
According to the fourth embodiment, by arranging the conductors 101A, 101B, 101C having the recess 402, the region having a high current density can be made into the facing surface of each of the three- phase conductors 101A, 101B, 101C, and the conductors can be separated from each other. The same effect as when the distance is shortened can be obtained.
1…バスダクト
2…筐体
100、100A、100B、100C…導体
101A、101B、101C…凹部を有する導体
102…磁性体
103…非磁性体
104…異種金属間腐食防止部
199…導体電流
301…固定具
401…突起 1 ...Bus duct 2 ... Housing 100, 100A, 100B, 100C ... Conductors 101A, 101B, 101C ... Conductors with recesses 102 ... Magnetic material 103 ... Non-magnetic material 104 ... Galvanic corrosion prevention part 199 ... Conductor current 301 ... Fixed Tool 401 ... Protrusion
2…筐体
100、100A、100B、100C…導体
101A、101B、101C…凹部を有する導体
102…磁性体
103…非磁性体
104…異種金属間腐食防止部
199…導体電流
301…固定具
401…突起 1 ...
Claims (9)
- 筐体と、
前記筐体内に配置された導体とを有し、
前記筐体は、
非磁性体と磁性体を含み、前記非磁性体と前記磁性体の間には異種金属間腐食防止部を有するバスダクト。 With the housing
It has a conductor arranged in the housing and has
The housing is
A bus duct containing a non-magnetic material and a magnetic material, and having a galvanic corrosion prevention portion between the non-magnetic material and the magnetic material. - 請求項1に記載のバスダクトにおいて、
前記異種金属間腐食防止部は、絶縁材であるバスダクト。 In the bus duct according to claim 1,
The galvanic corrosion corrosion prevention portion is a bus duct that is an insulating material. - 請求項1に記載のバスダクトにおいて、
前記非磁性体がステンレス鋼であり、
前記磁性体が鉄材であり、
前記異種金属間腐食防止部は金属であるバスダクト。 In the bus duct according to claim 1,
The non-magnetic material is stainless steel
The magnetic material is an iron material,
The anti-corrosion portion between dissimilar metals is a metal bus duct. - 請求項1に記載のバスダクトにおいて、
前記非磁性体は重力と反対方向に配置され、
前記磁性体は、重力方向に配置されるバスダクト。 In the bus duct according to claim 1,
The non-magnetic material is arranged in the direction opposite to gravity.
The magnetic material is a bus duct arranged in the direction of gravity. - 請求項1に記載のバスダクトにおいて、
前記非磁性体は突起を有するバスダクト。 In the bus duct according to claim 1,
The non-magnetic material is a bus duct having protrusions. - 請求項1に記載のバスダクトにおいて、
前記非磁性体は黒色塗装がされたバスダクト。 In the bus duct according to claim 1,
The non-magnetic material is a bus duct painted black. - 請求項1に記載のバスダクトにおいて、
複数の前記導体のうち、前記筐体との距離が最も短い第1の導体がある場合には、前記第1の導体に最も近い位置にある前記筐体は前記非磁性体であるバスダクト。 In the bus duct according to claim 1,
When there is a first conductor having the shortest distance from the housing among the plurality of conductors, the housing located closest to the first conductor is a bus duct which is the non-magnetic material. - 請求項1に記載のバスダクトにおいて、
前記磁性体と前記非磁性体と前記異種金属間腐食防止部を固定する固定具を有し、前記固定具は、異種金属間腐食防止用のメッキが施されるバスダクト。 In the bus duct according to claim 1,
A bus duct having a fixture for fixing the magnetic material, the non-magnetic material, and the galvanic corrosion prevention portion, and the fixture being plated for galvanic corrosion prevention. - 請求項1に記載のバスダクトにおいて、
複数の前記導体は、前記導体それぞれが対向する面と反対側に凹部を有するバスダクト。 In the bus duct according to claim 1,
The plurality of conductors are bus ducts having recesses on the opposite sides of the surfaces on which the conductors face each other.
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JPS52143640U (en) * | 1976-04-26 | 1977-10-31 | ||
JPS58218804A (en) * | 1982-06-15 | 1983-12-20 | 吉田 稔 | Device for grounding bus duct |
JP2016015804A (en) * | 2014-07-01 | 2016-01-28 | 関電プラント株式会社 | Pipeline internal inspection device |
-
2020
- 2020-03-24 JP JP2020052548A patent/JP7309646B2/en active Active
- 2020-09-01 WO PCT/JP2020/033135 patent/WO2021192353A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS477698U (en) * | 1971-02-19 | 1972-09-28 | ||
JPS51112096U (en) * | 1975-03-06 | 1976-09-10 | ||
JPS52143640U (en) * | 1976-04-26 | 1977-10-31 | ||
JPS58218804A (en) * | 1982-06-15 | 1983-12-20 | 吉田 稔 | Device for grounding bus duct |
JP2016015804A (en) * | 2014-07-01 | 2016-01-28 | 関電プラント株式会社 | Pipeline internal inspection device |
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JP7309646B2 (en) | 2023-07-18 |
JP2021153354A (en) | 2021-09-30 |
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