Ferrite cores and single air gaps are very common as this technique of a single gap is able to delay the core saturation and as a results increase the cores performance. However its not all good as these relatively large single gaps cause higher fringing flux which will lead to additional copper losses in the windings, especially when operating at high frequencies. Now single gaps aren’t bad by any means as the pros out way the cons, however can we improve this technique even further and reduce the cons ?
Let me introduce Distributed Air Gaps !
This technique implements multiple but smaller identical air gaps across the center limb of the ferrite core which is an elegant solution for reducing electromagnetic emissions and thus reducing the heating effect. Wondering how much of an impact this could truly have ? well results have shown the distributed air gaps can reduce copper losses by up to 70%!
Not convinced ? just check out the below hotspot comparison between a single air gap and 3 distributed air gaps (This is a comparison in the winding area on a ETD29/16/10-N87 from TDK).
Standard ferrite cores available with distributed air gaps are in geometries E, EQ, ER, ETD, PM and PQ core designs from TDK in all of the EPCOS Power materials. However is this not exactly what you are looking for? well fear not as our in-house machine shop has you covered, we can machine bespoke ferrite solutions including distributed air gaps! If you have a unique requirement and need rapid prototyping then get in touch with on any of the below means and we are happy to help.