In this study, we propose a high-frequency equivalent circuit of a ferrite common mode choke considering DC superimposition characteristics. Given that impedance solely changes at low frequencies as DC current increases, the equivalent circuit consists of two parts: an inductor with DC dependence whose impedance is dominant at low frequencies and a partial circuit without DC dependence whose impedance is dominant at high frequencies. The effectiveness of the proposed circuit is experimentally verified using coils with Mn-Zn and Ni-Zn ferrite cores.
