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Traftor windings changing the rules

Traftor toroidal flat wire winding technology

Round wire limitations: frequencies >20kHz

Round wire toroidal technology brings best efficiency in frequencies up to 20kHz. In higher frequencies, the so-called skin effect, with electrons travelling mainly on the surface area of the conductor instead of through the entire cross section, increases AC resistance. In this typology, flat wire technology is often an efficient alternative.

Traftor flat wire inductor

Traftor flat wire inductor

Flat wire limits skin effect

With up to 60% more surface area than round wire with same cross section area, flat wire limits better  skin effect at higher frequencies. Providing higher area for current to flow, flat wire technology makes it possible to design higher current solutions.

When very limited space is an issue

Filling factor with flat wire technology can reach close to 93-95%. In some specific applications, flat wire is just the only solutions to fit in a very limited space. Design limitation for flat wire is naturally that only one parallel can be winded compared to up to 8 parallel on round wire designs.

Typical flat wire applications

Flat wire technology is suited in most power supply applications. UPS, solar, automotive, industry…

Flat wire powder core inductor Traftor

Flat wire powder core inductor Traftor

Design: how to choose between flat and round wire technology?

At Traftor, using FEA software (finite element analysis) combined with our own developed equations and software, we are able to compare round and flat wire solutions. Therefore we provides best designs according to parameters and constraints, making it simple for our customers to evaluate and make the right choice.→

Inductors – Tranformers

Toroidal technology explained

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