I measured the AC resistance of my customized inductor with network analyzer of core E70. I got 23mohms AC resistance and 2.3mohm DCR for 14uH inductor with 8 number of turns using litz wire(1400) of 4.3mm diameter. I also got 30mohm AC resistance and 11mohm DCR for 54uH inductor with 16 number of turns using different litz wire(1050) of 2.8mm diameter. Both measured at same frequency. I am confused now, on which factor AC resistance depend upon. I thought I should have gotten more AC resistance for 54uH inductor. Is it depend on the type of litz wire we use? or number of small wire? How can I reduce the AC resistance? Please let me know. Thank you