As an important equipment for power transmission, the design of the copper shell of dense bus duct must meet the dual requirements of mechanical strength and electromagnetic shielding at the same time, which is crucial to ensure the stable operation of the power system and the safety of equipment. To achieve both, it is necessary to comprehensively consider and optimize from multiple aspects such as material selection, structural design, and manufacturing process.
In terms of material selection, pure copper is not necessarily the best choice. Although pure copper has excellent conductivity and is conducive to electromagnetic shielding, its hardness is relatively low, its mechanical strength is insufficient, and it is difficult to withstand large external impact and pressure. Therefore, copper alloy materials are often used in actual design. By adding other metal elements, copper alloys significantly improve hardness and tensile strength while maintaining good conductivity. For example, brass formed by adding zinc elements not only has enhanced hardness, but also has better wear resistance. On the basis of ensuring the electromagnetic shielding effect, it can effectively improve the shell's ability to resist external collision and extrusion, making the bus duct less likely to deform and damage during installation and use.
Structural design is a key link in taking into account both mechanical strength and electromagnetic shielding effects. In order to enhance mechanical strength, the copper shell will adopt a special structural form. The double-layer structure design is more common. The inner layer is responsible for electromagnetic shielding, and the good electrical conductivity of copper is used to reflect or absorb electromagnetic interference. The outer layer focuses on improving mechanical properties, and the rigidity and stability of the shell are enhanced by thickening or using reinforcing ribs. In the shape design of the shell, sharp edges and corners are also avoided, and arc transitions or smooth curved surfaces are used, which can reduce stress concentration and prevent cracks when stressed, without affecting the continuity of electromagnetic shielding. In addition, the openings and interfaces on the shell are reasonably arranged to ensure that the overall mechanical strength and shielding performance are not weakened while meeting functional requirements.
The manufacturing process has a direct impact on the performance of the copper shell. The quality of the welding process determines the firmness of the connection between the various parts of the shell. High-quality welding, such as argon arc welding, can achieve a close connection between copper and copper, and the weld is uniform and strong, which not only ensures the mechanical integrity of the shell, but also maintains a good conductive path to ensure the effectiveness of electromagnetic shielding. If the welding quality is poor, problems such as cold welding and pores will occur, which will not only reduce the mechanical strength of the shell, but also may form electromagnetic leakage points, affecting the shielding effect. In the process of shell molding, precise processing accuracy is also very important. Excessive dimensional error will lead to loose fitting of parts, which will not only affect mechanical stability, but also may damage the sealing of electromagnetic shielding.
In order to further improve the electromagnetic shielding effect, the dense bus duct copper shell will also adopt a multi-point grounding design. By setting grounding terminals at multiple locations of the shell to form a low-impedance grounding path, the induced charge can be effectively and quickly guided away, avoiding eddy currents and reducing electromagnetic energy loss and leakage. At the same time, sealing materials with good conductive properties will be used at the joints of the shell to ensure the conductive continuity of the connection and prevent electromagnetic interference from leaking out of the gap. These measures will not have a negative impact on the mechanical strength while ensuring the electromagnetic shielding performance. On the contrary, they enhance the overall stability of the shell through tight connections.
In practical applications, the adaptability of the copper shell in different environments also needs to be considered. For example, in a high-temperature environment, a copper alloy material with good high-temperature resistance is selected to avoid softening and strength reduction of the shell due to temperature increase, and at the same time, it is also necessary to ensure that its electromagnetic shielding performance at high temperatures does not significantly attenuate. In a humid environment, the copper shell is treated with surface anti-corrosion treatment, such as tin plating and nickel plating, to prevent copper from being oxidized and corroded, affecting mechanical strength and conductivity, and thus destroying the electromagnetic shielding effect.
During the design process, the performance of the copper shell is also verified through simulation analysis and actual testing. Computer software is used to simulate the stress and electromagnetic distribution of the shell under different working conditions, and the weak links in the design are discovered in advance and optimized. After the sample is manufactured, mechanical strength tests such as compression and impact tests, as well as electromagnetic shielding effectiveness tests are carried out. The design is adjusted and improved according to the test results to ensure that the final product can meet the strict requirements of mechanical strength and electromagnetic shielding at the same time.
The design of the copper shell of dense bus duct needs to start from multiple angles such as materials, structure, process, environmental adaptability, and test verification, and comprehensively use a variety of technical means to ensure good electromagnetic shielding effect while improving mechanical strength, so as to achieve the organic unity of the two, thereby providing reliable and stable protection for the power transmission system.
