A method to model the conducted EMI propagation path for PFC

In order to evaluate the electromagnetic compatibility (EMC) performance of a PFC unit more accurately, it is necessary to establish a high frequency (HF) equivalent circuit model of its conducted electromagnetic interference (EMI) propagation path. In this paper, the HF equivalent circuit model of the passive elements in the PFC unit is established and their stray parameters are extracted by measurement, and the HF circuit parameters of its main PCB tracks are calculated by the electromagnetic field calculation software. The HF equivalent circuit model of the conducted EMI propagation path is established by connecting the models of the passive elements and its PCB tracks in the PFC unit. A method to validate the model is proposed. With the same pulse voltage applied to the same nodes in the PFC unit, a comparison is made between the simulation and measurement results of the voltage on the resistance in the LISN and their spectrums over the frequency range from 150 kHz to 30 MHz. The agreement between the results validates the HF equivalent circuit model, and shows that the validation method is effective to analyze the conducted EMI characteristics.