An equivalent circuit analysis has been studied to realize the design of quasi-distributed constant line filter. This analysis is based on a physical model derived from a structure of a quasi-distributed constant transmission line composed of winding of a common-mode choke coil combined with a grounding plate. A target frequency band of the analysis is set from 150 kHz to 100 MHz in consideration of the Comité international spécial des perturbations radioélectriques (CISPR) regulation and trends of power converter circuits with SiC or GaN semiconductors. In modeling of the equivalent circuit, the circuit parameters are classified into a series impedance element and a shunt admittance element. Parameters of the series impedance element can be obtained by using frequency dependences of the relative complex permeability of a Mn-Zn ferrite core. To identify parameters of the shunt admittance element, impedance between a short-circuited end of the series impedance element and the grounding plate are measured. Then parameters can be obtained by performing circuit calculation based on observed resonant frequencies of the measured frequency characteristic of the impedance, values of the impedance and reactance, and the like. The calculated attenuation characteristic using identified equivalent circuit parameters shows good agreement with the measurement result.
J-STAGEがリニューアルされました！ https://www.jstage.jst.go.jp/browse/-char/ja/
