Litzledningar

Litzledningar, also known as Litz wire or stranded wire, are a type of electrical conductor composed of many thin, individually insulated strands of wire twisted or braided together. The primary purpose of this construction is to reduce the skin effect and proximity effect at radio frequencies. In AC circuits, current tends to flow on the surface of a conductor. At higher frequencies, this "skin effect" becomes more pronounced, limiting the effective cross-sectional area of the wire and increasing its resistance. By using many small, insulated strands, the total surface area of the conductor is increased, and the current is distributed more evenly across the available surface of each strand.

The insulation on each individual strand prevents the strands from electrically connecting, ensuring that each strand carries its share of the current. This distributed current flow significantly lowers the AC resistance compared to a solid conductor of equivalent cross-sectional area, especially at frequencies ranging from kilohertz to megahertz. Litzledningar are commonly used in applications where high efficiency and low losses are crucial at radio frequencies, such as in radio frequency transformers, inductors, and high-frequency power converters. The number of strands, their gauge, and the way they are twisted or braided are all factors that can be optimized for specific frequency ranges and current requirements.