Compared nanocrystalline and ferrite optimized Common Mode Choke for RFI filters suitable as compact components

Waeckerlé T. ⁽¹⁾, Save T. ⁽¹⁾, Vachey B. ⁽²⁾, Gautard D. ⁽²⁾,

¹⁾ Cie IMPHY ALLOYS (Arcelor Group)

Research Center, 58160 Imphy, FRANCE

²⁾ Cie Mécagis (Arcelor Group)

315 Rue du Maréchal Juin 45200 Amilly, France

¹⁾thierry.waeckerle@iup.arcelor.com, Tel  +33 3 86 21 39 63, Fax +33 3 86 21 31 11

                        Abstract – The design of Common mode chokes for Radio Frequency Interference filter is considered, explained and applied to the compared magnetic core characterization and computation between ferrite and nanocrystalline materials. The latter shows some better insertion losses at low frequencies when comparison is made with the same component characteristics. The volume of the core can be reduced by 50 to 80% when an appropriated ferrite is replaced by a well-chosen nanocrystalline core, as a result of its superimposed advantages of high and tailored permeabilities, high saturation and inductive behavior near CMC resonance. Moreover, concerning new nanocrystalline wound cores, it is shown in the very most cases of CMC designs with different requirements ranging between 1 and 10kW, that the optimum of component volume minimization is reached when the relative permeability is standing near 20 000 as a compromise between non saturation and damping effect requirements. Finally the marked temperature stability of SMC performances up to 150°C brings other very interesting advantage to nanocrystalline materials in hardly thermally stressed power electronics.