Because of the excellent electrical conductivity of copper materials, automotive high-voltage wiring harnesses are generally procured copper materials as conductors. (20 ℃ environment, the resistance of copper is 0.0185 Ωmm2/m, aluminum resistance is 0.0294 Ωmm2/m). In the case of high current, the working temperature rise of copper wire is lower, on the one hand, it can reduce the heat loss during power transmission, on the other hand, the excellent thermal conductivity of copper material also ensures that the working temperature of high-voltage wiring harnesses is stabilized within the safety range. At the same time, due to excellent electrical conductivity, under the same load, the cross-sectional area of the copper wire can be smaller, which can effectively help the flexible arrangement of high-voltage wiring harnesses, including smaller turning radius (high-voltage wiring harnesses generally need to be more than the diameter of the wire harness more than 5 to 6 times); In addition, the finer wiring harnesses can reduce the bending stress, installation of wiring harnesses, connectors insertion and extraction force is smaller, to help reduce the difficulty of installation and maintenance to Improve the stability and reliability of the assembly; and, smaller cross-sectional area can help high-voltage wiring harnesses are flexibly arranged to fit the metal body grooves, corners, or close to the metal body layout to effectively reduce electromagnetic interference.
In addition to good electrical conductivity, copper as a high-voltage wire harness conductor material is another advantage of better tensile strength and bending properties. Copper metal has good mechanical properties, tensile strength of 200-240 MN/M2, elongation up to 50%, its good plasticity makes it easy to process, has a high plastic deformation capacity, can be calendered, extruded and stretched and other pressure processing methods made of a variety of shapes and sizes of the products, and the use of copper as a conductor of high-voltage wiring harness in the use of the process can withstand the vehicle traveling in the process of the occurrence of the Vibration and friction, with high reliability and longer service life.
Copper material also has good chemical stability, good corrosion resistance, and easy to weld. Vehicle operating environment is complex and harsh, high-voltage wire harnesses and terminal connectors will inevitably work in the humidity, salt spray and other corrosive environment. According to the traditional automotive wiring harness experience, in the humid, high temperature and vibration environment, such as friction and collision with other parts, easy to insulator wear, loose joints, wire corrosion and other phenomena, which leads to disconnection or short-circuit and other failures. Since high-voltage wiring harnesses carry higher voltages, higher currents, and have greater stress on terminals and connectors, there are higher safety requirements that require conductor materials with better chemical stability. High-quality copper materials can both ensure that the terminals and connectors to maintain good contact for a long time, to avoid the occurrence of galvanic corrosion, but also to slow down the insulation layer aging or damaged, the harness conductor by corrosion. And this area is also other materials as a high-voltage wire harness conductor need to conduct comprehensive research to verify one of the main difficulties.
Safety is the most important indicator of high-voltage wiring harness, high-voltage wiring harness safety design is mainly reflected in the insulation, voltage protection, overload, connector IP level, equipotential equalization, high-voltage wiring harness routing and other aspects. From the safety point of view, the use of better electrical conductivity and thermal conductivity of the material is conducive to optimizing the energy efficiency of the high-voltage wiring harness, reduce the temperature rise; the use of better tensile strength and plasticity of the material helps to enhance the high-voltage wiring harness in the production of assembly and vehicle operation in the face of vibration and friction in the case of the reliability and is conducive to the optimization of the wiring harness of the spatial arrangement; the use of more chemically stable materials can prevent corrosion occurs The use of more chemically stable materials prevents corrosion and ensures good contact between the high-voltage harness terminals and the connectors, reducing the safety risks associated with poor contact.
