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# Analysis of eddy currents on the busbar

• Categories:Zhongrui News
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• Time of issue:2019-05-29 17:44
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(Summary description)Under time-varying conditions, the corresponding induced electromotive force is different due to the different current paths through the points on the loop section, and thus the current density at each point is also different. In other words, in addition to the uniform current based on the uniform resistivity of the medium, eddy currents may occur due to electromagnetic induction, that is, the skin effect and the proximity effect occur, and the current distribution on the cross section is uneven, including phase inconsistency. . The extent of skin effect and proximity effect is related to the shape and frequency of the conductor cross-section, and the proximity effect is also related to the distance between adjacent conductors or between circuits. For most copper, aluminum busbars or power lines operating at power frequency, except for special cases, the two effects are generally not large because the conductor cross section is not large and the distance between the conductors is not very small. This kind of conductor is called a linear conductor, and its circuit is called a linear loop. The external inductance of the linear loop is the main part of its total inductance, and the eddy current affects only the magnetic flux inside the conductor and a small portion of the external magnetic flux in the vicinity of the conductor. Therefore, even if there is a certain eddy current, its influence on the inductance value is still small (less than the influence of the resistance loss). In addition, the accuracy of the inductance calculation is not as important as the resistance value. Therefore, the general power line inductance calculation can assume that the current is evenly distributed in the cross section, which greatly simplifies the calculation. However, when eddy current effects are particularly large, they must be specifically considered. For example, the low-voltage high-current lead of the outer casing or the metallurgical furnace of the closed busbar is the same, and the busbar housing is shielded by a magnetic field after the good conductor aluminum alloy, which better solves the problem that the closed busbar is easy to generate eddy current. Steel busbars or conductors, due to their large size and non-linearity, have a strong skin effect. For this purpose, an aluminum-insulated air-insulated busway has been developed, which solves the problem of closed busbars accumulating in the skin effect.

# Analysis of eddy currents on the busbar

(Summary description)Under time-varying conditions, the corresponding induced electromotive force is different due to the different current paths through the points on the loop section, and thus the current density at each point is also different. In other words, in addition to the uniform current based on the uniform resistivity of the medium, eddy currents may occur due to electromagnetic induction, that is, the skin effect and the proximity effect occur, and the current distribution on the cross section is uneven, including phase inconsistency. . The extent of skin effect and proximity effect is related to the shape and frequency of the conductor cross-section, and the proximity effect is also related to the distance between adjacent conductors or between circuits. For most copper, aluminum busbars or power lines operating at power frequency, except for special cases, the two effects are generally not large because the conductor cross section is not large and the distance between the conductors is not very small. This kind of conductor is called a linear conductor, and its circuit is called a linear loop. The external inductance of the linear loop is the main part of its total inductance, and the eddy current affects only the magnetic flux inside the conductor and a small portion of the external magnetic flux in the vicinity of the conductor. Therefore, even if there is a certain eddy current, its influence on the inductance value is still small (less than the influence of the resistance loss). In addition, the accuracy of the inductance calculation is not as important as the resistance value. Therefore, the general power line inductance calculation can assume that the current is evenly distributed in the cross section, which greatly simplifies the calculation. However, when eddy current effects are particularly large, they must be specifically considered. For example, the low-voltage high-current lead of the outer casing or the metallurgical furnace of the closed busbar is the same, and the busbar housing is shielded by a magnetic field after the good conductor aluminum alloy, which better solves the problem that the closed busbar is easy to generate eddy current. Steel busbars or conductors, due to their large size and non-linearity, have a strong skin effect. For this purpose, an aluminum-insulated air-insulated busway has been developed, which solves the problem of closed busbars accumulating in the skin effect.

• Categories:Zhongrui News
• Author:
• Origin:
• Time of issue:2019-05-29 17:44
• Views:
Information

Under time-varying conditions, the corresponding induced electromotive force is different due to the different current paths through the points on the loop section, and thus the current density at each point is also different. In other words, in addition to the uniform current based on the uniform resistivity of the medium, eddy currents may occur due to electromagnetic induction, that is, the skin effect and the proximity effect occur, and the current distribution on the cross section is uneven, including phase inconsistency. . The extent of skin effect and proximity effect is related to the shape and frequency of the conductor cross-section, and the proximity effect is also related to the distance between adjacent conductors or between circuits. For most copper, aluminum busbars or power lines operating at power frequency, except for special cases, the two effects are generally not large because the conductor cross section is not large and the distance between the conductors is not very small. This kind of conductor is called a linear conductor, and its circuit is called a linear loop. The external inductance of the linear loop is the main part of its total inductance, and the eddy current affects only the magnetic flux inside the conductor and a small portion of the external magnetic flux in the vicinity of the conductor. Therefore, even if there is a certain eddy current, its influence on the inductance value is still small (less than the influence of the resistance loss). In addition, the accuracy of the inductance calculation is not as important as the resistance value. Therefore, the general power line inductance calculation can assume that the current is evenly distributed in the cross section, which greatly simplifies the calculation. However, when eddy current effects are particularly large, they must be specifically considered. For example, the low-voltage high-current lead of the outer casing or the metallurgical furnace of the closed busbar is the same, and the busbar housing is shielded by a magnetic field after the good conductor aluminum alloy, which better solves the problem that the closed busbar is easy to generate eddy current. Steel busbars or conductors, due to their large size and non-linearity, have a strong skin effect. For this purpose, an aluminum-insulated air-insulated busway has been developed, which solves the problem of closed busbars accumulating in the skin effect.