Inductive coils and infinite charging coils that are wound with a plurality of thinner enameled wires or yarn-wrapped wires are not for the above reasons. The latter is often used in circuits with relatively high frequencies, such as magnetic antenna rod coils of radios, mid-circle coils of short-wave radios, high-frequency transformer coils of liquid crystal display lighting circuits, etc., usually by means of multiple thin wires. You may not know that the high-frequency current is in the conductor; the farther away from the conductor surface as it flows, the smaller the current inside the conductor is, which is exponentially distributed. In other words, the current inside the conductor tends to be several. When making a cross-section from a direction perpendicular to the direction of the current, the current intensity at the center of the circle is substantially equal to zero, and the farther away from the center of the circle, the stronger the current. There is only current in the portion of the edge of the conductor. In layman's terms, the current is concentrated on the surface of the conductor, which we call the SECT.

 

The main reason for this effect is that the changing electromagnetic field generates a vortex electric field inside the conductor, which is offset by the original current. Therefore, in a certain volume of space, the more wires used, the larger the surface area, the larger the surface area and the larger the current, the greater the utilization of the material, and the heating or signal attenuation of the wire will be reduced to meet our expectations. The parallel application of multiple strands can greatly reduce the skin effect, making the magnetic field generated by the current relatively uniform. In layman's terms, it provides a larger area of ​​the "skin" path for current. It can be seen from the test comparison that the high-frequency transformer with the same power volume is much larger than the single-wire and multi-strand line.