Brass electrical terminals face the challenge of skin effect during high-frequency current transmission. Essentially, when a high-frequency electromagnetic field interacts with a conductor, the opposing magnetic field generated by eddy currents suppresses internal current flow, causing current to concentrate on the conductor's surface, reducing the effective cross-sectional area and increasing the equivalent resistance. This effect reduces the material utilization of brass electrical terminals, increases transmission losses, and can even cause local overheating, compromising connection stability. Therefore, mitigating skin effect is key to improving the high-frequency performance of brass electrical terminals.
Optimizing conductor structure is a fundamental approach to mitigating skin effect. Adopting a flat design can significantly increase the surface-to-volume ratio of brass electrical terminals, ensuring more uniform current distribution. For example, switching from a circular cross-section to a rectangular or ribbon-like structure can reduce equivalent resistance at high frequencies. Multi-stranded wire technology breaks down brass conductors into multiple insulated strands and twists them together. Each strand independently carries current, effectively increasing the effective conductive area. This structure, widely used in RF transformers and high-frequency connectors, effectively distributes current density and mitigates the effects of skin effect.
Manipulating material properties provides key support for high-frequency applications in brass electrical terminals. Surface plating technology reduces surface resistance by coating with highly conductive materials (such as silver and nickel). Silver plating is a preferred option for high-frequency terminals due to its greater skin depth than copper and its strong oxidation resistance. However, the plating thickness must exceed the skin depth, otherwise the effectiveness will be limited. Regarding material selection, brass inherently has low magnetic permeability, making it suitable for high-frequency applications. However, direct contact with ferromagnetic materials (such as iron and nickel) should be avoided, as their high permeability exacerbates the skin effect, leading to a surge in AC resistance.
Transmission path reconstruction is a key breakthrough in high-frequency terminal design. Coaxial cable structures utilize an inner conductor diameter designed according to the skin depth (for example, the inner conductor diameter of a 50Ω cable is often twice the skin depth). This, combined with an outer conductor shielding layer, limits electromagnetic field leakage, achieving low-loss transmission of high-frequency signals. Waveguide structures are widely used in the microwave range (>1 GHz). They utilize the propagation properties of electromagnetic waves along metal surfaces, completely avoiding the skin losses associated with physical conductors. For PCB designs connecting brass electrical terminals, using wide and thin traces can increase signal transmission efficiency and reduce losses.
Electromagnetic shielding and thermal management technologies ensure stable operation of high-frequency terminals. Wrapping a magnetic shield around a conductor modifies the magnetic field distribution, making the current more evenly distributed. This is commonly seen in the outer layer design of high-frequency cables. Regarding thermal design, ohmic losses caused by the skin effect are concentrated on the conductor surface, which can easily lead to localized overheating. This requires improving thermal management by optimizing the heat dissipation structure (such as adding heat sink fins or using thermal adhesive) or selecting low-thermal-resistance materials (such as copper alloy). For example, silver plating on brass electrical terminals not only reduces resistance but also improves heat dissipation due to silver's high thermal conductivity.
Frequency and system architecture adjustments provide flexibility for mitigating skin effect. Lowering the operating frequency can directly increase the skin depth, but due to bandwidth requirements (for example, 5G communications cannot mitigate skin effect by frequency reduction), this approach is only suitable for scenarios with low frequency sensitivity. For power transmission systems involving brass electrical terminals, if there is sufficient frequency adjustment headroom, appropriate frequency reduction can significantly reduce high-frequency losses. Furthermore, distributed parameter circuit design, by treating the conductors as series/parallel networks of inductors, capacitors, and resistors, achieves impedance matching at high frequencies, indirectly mitigating the impact of skin effect. Skin effect mitigation must be integrated throughout the entire brass electrical terminal design, manufacturing, and testing process. From conductor structure innovation to material property optimization, and from transmission path reconstruction to electromagnetic shielding and thermal management, the synergy of multiple technologies can minimize the adverse effects of skin effect. With the widespread adoption of high-frequency applications such as 5G communications and satellite communications, brass electrical terminals must continuously iterate to achieve breakthroughs in high-frequency loss control, improved material utilization, and enhanced thermal stability to meet the future power system's demand for efficient and reliable connections.
