Simulating Saturation Behavior of Common Mode Chokes

Common Mode Chokes are widely used to suppress common mode and differential mode noise while compensating the magnetic field of the load current. The preferred measurement technique to characterize saturation behavior is small-signal inductance versus dc-bias. We recently presented a new method for simulating small signal inductance versus dc-bias currents [1, 2]. By using the proper material characteristics, this method allows the simulation of saturation effects due to differential mode and common mode currents. The simulation results are verified by measurements on a standard and a novel Common Mode Choke design under development.