Core Selection for High DC bias Application

[yopat]

Find this site out of desparation, I have problem finding suitable core material for my common mode choke. The problem is the huge DC bias, 11A, 31A and 38A. I tried amorphous core but the resulting choke is gigantic, and still the inductance gone to nothing. The required inductance is in the mH range. What kind of core should I use? And not even Hi-flux seems to prevail ....


Thanks so much in advance.

 

[electricuwe]

The trick of the common mode choke is to wind both (or all) conductors on one core so that the DC and low frequency currents cancel each other and do not generate magnetic flux in the core. If that is not the case in your application it's not a common mode choke.

 

[busbar]

e-w, is that a characteristic of "bifilar-" or "trifilar-wound" inductors?

 

[electricuwe]

busbar,

the term common-mode choke refers to the application (suppressing common mode currents) whereas bifilar or trifilar decribes the way the winding is manufactured (two or three wires are wound in parallel). Common mode chokes can be made with bifilar winding if the isolation requirements can be met.