Version 4
SHEET 1 2092 1376
WIRE -48 0 -48 -32
WIRE -48 112 -48 80
WIRE -48 240 -48 208
WIRE -48 352 -48 320
WIRE -48 480 -48 448
WIRE -48 592 -48 560
WIRE -48 720 -48 688
WIRE -48 832 -48 800
WIRE 80 -32 -48 -32
WIRE 96 208 -48 208
WIRE 96 448 -48 448
WIRE 96 688 -48 688
WIRE 208 -32 80 -32
WIRE 208 0 208 -32
WIRE 208 112 208 80
WIRE 208 208 96 208
WIRE 208 240 208 208
WIRE 208 352 208 320
WIRE 208 448 96 448
WIRE 208 480 208 448
WIRE 208 592 208 560
WIRE 208 688 96 688
WIRE 208 720 208 688
WIRE 208 832 208 800
WIRE 416 0 416 -32
WIRE 416 112 416 80
WIRE 544 -32 416 -32
WIRE 672 -32 544 -32
WIRE 672 0 672 -32
WIRE 672 112 672 80
FLAG 208 352 0
FLAG 96 208 L_TANH
FLAG 208 592 0
FLAG 96 448 L_ATAN
FLAG -48 112 0
FLAG 208 112 0
FLAG 80 -32 L_LIN
FLAG 208 832 0
FLAG -48 352 0
FLAG -48 592 0
FLAG 96 688 L_TANH2
FLAG -48 832 0
FLAG 416 112 0
FLAG 672 112 0
FLAG 544 -32 L_LIN1
SYMBOL ind 192 224 R0
WINDOW 39 36 108 Left 0
SYMATTR SpiceLine Rser=1m
SYMATTR InstName L2
SYMATTR Value flux=(100u-3u)*8*tanh(x/8) + 3u*x
SYMBOL ind 192 464 R0
WINDOW 39 36 108 Left 0
SYMATTR SpiceLine Rser=1m
SYMATTR InstName L3
SYMATTR Value flux=(100u-3u)*7*atan(x/7)+3u*x
SYMBOL ind 192 -16 R0
WINDOW 39 36 108 Left 0
SYMATTR SpiceLine Rser=1m
SYMATTR InstName L1
SYMATTR Value flux=100u*x
SYMBOL current -48 80 M180
WINDOW 123 26 -43 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 40 69 Left 0
WINDOW 3 24 -8 Left 0
SYMATTR Value2 AC 0.159155
SYMATTR InstName I1
SYMATTR Value {Idc}
SYMBOL ind 192 704 R0
WINDOW 39 36 108 Left 0
SYMATTR SpiceLine Rser=1m
SYMATTR InstName L4
SYMATTR Value flux=(70u)*6.5*tanh(x/6.5) + 3u*x +27u*20*tanh(x/20)
SYMBOL current -48 320 M180
WINDOW 123 26 -43 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 40 69 Left 0
WINDOW 3 24 -8 Left 0
SYMATTR Value2 AC 0.159155
SYMATTR InstName I2
SYMATTR Value {Idc}
SYMBOL current -48 560 M180
WINDOW 123 26 -43 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 40 69 Left 0
WINDOW 3 24 -8 Left 0
SYMATTR Value2 AC 0.159155
SYMATTR InstName I3
SYMATTR Value {Idc}
SYMBOL current -48 800 M180
WINDOW 123 26 -43 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 40 69 Left 0
WINDOW 3 24 -8 Left 0
SYMATTR Value2 AC 0.159155
SYMATTR InstName I4
SYMATTR Value {Idc}
SYMBOL ind 656 -16 R0
WINDOW 39 36 108 Left 0
SYMATTR SpiceLine Rser=1m
SYMATTR InstName L5
SYMATTR Value 100µ
SYMBOL current 416 80 M180
WINDOW 123 26 -43 Left 0
WINDOW 39 0 0 Left 0
WINDOW 0 40 69 Left 0
WINDOW 3 24 -8 Left 0
SYMATTR Value2 AC 0.159155
SYMATTR InstName I5
SYMATTR Value {Idc}
TEXT -64 -144 Left 0 !.ac list 1e6
TEXT -64 -112 Left 0 !.step param Idc 0 10 .01
TEXT -64 -584 Left 0 ;Nonlinear(saturating) Inductors\n \nV = Iac*2*pi*f*L\n \nExample f=1e6 = 1 MHz , Iac=1/(2+pi), Rser has been neglected\nV = 1e6*L \nV = L [uH]    means 1V/uH\n \nL0 = Lcore+Lair   inductance at 0A DC\n \nflux=Lcore*a*tanh(x/a) + Lair*x\n \nDon't forget to set a reasonable value for Rser in the final schematic.\nThere is also some value of Cpar especially in mult-layered coils.
TEXT 176 -64 Left 0 ;V=1V/uH
TEXT -72 1080 Left 0 !.measure  AC  Vtanh0 FIND mag(V(L_tanh)) at 0\n.measure  AC  Vtanh1 FIND mag(V(L_tanh)) at 1\n.measure  AC  Vtanh2 FIND mag(V(L_tanh)) at 2\n.measure  AC  Vtanh3 FIND mag(V(L_tanh)) at 3\n.measure  AC  Vtanh4 FIND mag(V(L_tanh)) at 4\n.measure  AC  Vtanh5 FIND mag(V(L_tanh)) at 5\n.measure  AC  Vtanh6 FIND mag(V(L_tanh)) at 5\n.measure  AC  Vtanh7 FIND mag(V(L_tanh)) at 7\n.measure  AC  Vtanh8 FIND mag(V(L_tanh)) at 8\n.measure  AC  Vtanh9 FIND mag(V(L_tanh)) at 9\n.measure  AC  Vtanh10 FIND mag(V(L_tanh)) at 10
TEXT -72 952 Left 0 ;* Sum the squared differences of all measured points for the cost-function.\n* The Perl-optimizer would use the result of this cost-function to fit the flux-function.\n \n.measure cost PARAM (100-Vtanh0)*(100-Vtanh0) + ....