Optimal design of EMI filters for single-phase boost PFC circuits

Mains-connected boost power factor correction (PFC) circuits are employed in order to meet EMI standards. The EMI filter together with the boost inductor has to attenuate the high frequency (HF) voltage component to the mains side of the converter. In this paper, it is shown on the example of a single-phase PFC rectifier with nominal power P_N = 1:5kW, mains frequency f_mains = 50 Hz, DC voltage V_DC = 400V, and mains voltage v_mains = 230V how the switching frequency and the relative ripple of the boost inductor current affect the filter and boost inductor volume and losses. With it, the optimum switching frequency and ratio of the ripple and fundamental current amplitude with respect to volume and losses is found.